Jan Harald Røtterud

• Pollmann, Christian Thomas; Thomas, Owen Matthew Truscott; Røtterud, Jan Harald; Dale, Håvard; Wulf, Mireille Wilhelmina Huberta & Skråmm, Inge (2026). Association between superficial surgical site infection and revision after primary total hip arthroplasty: a cohort study of 3,242 patients. Acta Orthopaedica. ISSN 1745-3674. 97, p. 478–483. doi: 10.2340/17453674.2026.46223. Full text in Research Archive Show summary

  Background and purpose: We aimed to evaluate whether a superficial surgical site infection (SSI) after primary total hip arthroplasty (THA) is associated with an increased risk of subsequent revision hip arthroplasty for any cause. Methods: This is a single-center, observational study based on data from the Norwegian Arthroplasty Register (NAR) and the local infection surveillance program. All patients operated on with a primary THA at our institution from January 1999 through December 2019 were eligible for the study. The risk of revision surgery for any cause was compared between the exposed (superficial SSI) and the unexposed group (no SSI) with frequentist (Cox regression) and Bayesian survival analysis. Results: 3,242 patients were included in the study. Median follow-up in the NAR was 7, minimum follow-up was 4 years. 27 patients were registered with a superficial SSI. A Cox regression analysis adjusted for sex, age, American Society of Anesthesiologists Physical Status (ASA) class, duration of surgery, and year of surgery gave an adjusted hazard ratio of 1.4 (95% confidence interval: 0.3–5.9, P = 0.6) for the risk of revision for any cause in the exposed group (superficial SSI) compared with the unexposed group (no SSI). A Bayesian survival model, adjusted for the same covariates, gave a censored time coefficient of 0.5 (95% credible interval: 0.1–0.9), with a corresponding very low (1%) probability of an increased risk of revision for any cause in the exposed group. Conclusion: We showed no association between superficial SSI and revision after primary THA. Thus, our data does not support the dogma that superficial SSIs after primary THA do not exist.

• Kjennvold, Stian; Røtterud, Jan H; Forssblad, Magnus; Engebretsen, Lars; Årøen, Asbjørn & Ulstein, Svend (2025). Debridement or Microfracture for Full-Thickness Cartilage Lesions in Anterior Cruciate Ligament Reconstruction: A 10-Year Cohort Study of 326 Patients in Norway and Sweden. Orthopaedic Journal of Sports Medicine (OJSM). 13(10). doi: 10.1177/23259671251381340. Full text in Research Archive Show summary

  Background: It is well-established that patients undergoing anterior cruciate ligament reconstruction (ACLR) have a less favorable prognosis if a concomitant full-thickness cartilage lesion is present at the time of surgery. However, the long-term benefits of surgically addressing these cartilage lesions remain uncertain. Purpose: To evaluate whether the most used surgical treatments for cartilage lesions influenced patient-reported outcomes 10 years after ACLR. Study Design: Cohort study; Level of evidence, 2. Methods: This study was based on a cohort of all patients with primary unilateral ACLR in the Norwegian and Swedish knee ligament registries from January 2005 through December 2008 (n = 15,783). A total of 1012 (6.4%) patients had ≥1 full-thickness cartilage lesion (International Cartilage Regeneration & Joint Preservation Society grade 3 or 4) at the time of reconstruction. Of these, 644 patients met the inclusion criteria. At a mean (± SD) follow-up of 10.1 ± 0.2 years, 326 (51%) of the patients had completed the Knee injury and Osteoarthritis Outcome Score (KOOS). The treatment categories documented in the Scandinavian knee ligament registries were microfracture, debridement, no treatment, or other/unknown. Patients who did not receive surgical treatment for their full-thickness cartilage lesions served as the reference group and were compared with those who underwent microfracture or debridement. Multiple linear regression, with adjustment for possible confounders, was used to evaluate associations between surgical treatment of cartilage lesions and patient-reported outcomes for all KOOS subscales 10 years after ACLR. Results: Of the 326 patients available at the 10-year follow-up, 182 (56%) had not received surgical treatment for their cartilage lesions. A total of 68 (21%) patients had been treated with debridement, and 76 (23%) patients had been treated with microfracture. No significant association with KOOS scores was observed for debridement or microfracture compared with the reference group without surgical treatment of their cartilage lesion. The unadjusted data showed a trend toward poorer outcomes with microfracture compared with debridement, but this difference was not statistically significant. Conclusion: Debridement and microfracture showed no significant association with patient-reported outcomes 10 years after ACLR in patients with concomitant full-thickness cartilage lesions, compared with those who did not receive surgical treatment for their cartilage lesion.

• Kjennvold, Stian; Ulstein, Svend; Årøen, Asbjørn; Forssblad, Magnus; Engebretsen, Lars & Røtterud, Jan H (2025). Effect of Focal Cartilage Lesions on Patient-Reported Outcomes After Anterior Cruciate Ligament Reconstruction: A 10-Year Nationwide Cohort Study of 7040 Patients. American Journal of Sports Medicine. ISSN 0363-5465. 53(10), p. 2407–2414. doi: 10.1177/03635465251350398. Full text in Research Archive Show summary

  Background: Focal cartilage lesions are commonly associated with anterior cruciate ligament injuries. The long-term effect of these lesions on patient-reported outcomes after anterior cruciate ligament reconstruction (ACLR) remains unclear. Purpose: To determine the effect of cartilage lesions—partial thickness (International Cartilage Regeneration and Joint Preservation Society grades 1 and 2) and full thickness (grades 3 and 4)—on patient-reported outcomes 10 years after ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: The study included all patients with primary unilateral ACLR enrolled in the Norwegian Knee Ligament Registry and Swedish Knee Ligament Registry from 2005 through 2008 (n = 15,783). At a mean follow-up of 10.1 years (SD, 0.2), 7040 (45%) patients completed the Knee injury and Osteoarthritis Outcome Score (KOOS). Multiple linear regression analyses were used to evaluate any associations between concomitant cartilage lesions and KOOS outcomes 10 years after ACLR. Results: Of the 7040 patients available at 10-year follow-up, 1425 (20.3%) had partial-thickness cartilage lesions at the time of ACLR, and 495 (7.0%) had full-thickness cartilage lesions. Multiple linear regression analyses revealed that partial- and full-thickness cartilage lesions were associated with significantly inferior scores across all KOOS subscales as compared with patients without cartilage lesions. Patients with full-thickness lesions had less postoperative improvement after ACLR in all KOOS subscales as compared with patients with partial-thickness lesions. Conclusion: Patients with concomitant partial- or full-thickness cartilage lesions reported significantly worse outcomes in all KOOS subscales 10 years after ACLR as compared with patients without cartilage lesions.

• Mikaelsen, Jan Rune; Jakobsen, Rune Bruhn; Røtterud, Jan H & Randsborg, Per-Henrik (2024). Body Mass Index Did Not Affect the Risk of Revision 3-9 Years After Total Knee Replacement Surgery. Arthroplasty Today. 27. doi: 10.1016/j.artd.2024.101376. Full text in Research Archive Show summary

  Background There are conflicting reports in the literature regarding the risk of revision after primary total knee replacement (TKR) in obese patients. The purpose of this study was to investigate if body mass index (BMI) influences the risk of revision 3-9 years after primary TKR. Methods All patients undergoing a primary TKR in our institution from 2014 to 2018 were included in a retrospective study. The effect of BMI on all-cause revision was estimated in a logistic regression analysis. A directed acyclic graph was created to identify variables affecting the primary endpoint (revision). According to the directed acyclic graph, adjustment was only needed for age and smoking. However, we also included variables thought to influence the revision risk based on clinical experience and previous research. The final logistic regression analysis was therefore adjusted for age, sex, smoking status, diabetes mellitus and the American Society of Anesthesiologists classification. Results One thousand fifty-nine primary TKR patients with a mean age of 68.1 (standard deviation 9.4) years were included. There were 609 (57.5%) women, and the median follow-up time was 5.6 (range 3.0-9.0) years. There were 41 (3.9%) revisions. BMI did not affect the risk of revision when adjusted for relevant covariates in a multivariate logistic regression analysis (odds ratio 0.99, 95% confidence interval 0.93-1.05, P = .6). Conclusions BMI did not influence the risk of revision rate 3-9 years after TKR.

• Øiestad, Britt Elin; Årøen, Asbjørn; Røtterud, Jan H; Østerås, Nina; Jarstad, Even & Grotle, Margreth [Show all 7 contributors for this article] (2023). The efficacy of strength or aerobic exercise on quality of life and knee function in patients with knee osteoarthritis. A multi-arm randomized controlled trial with 1-year follow-up. BMC Musculoskeletal Disorders. 24(1). doi: 10.1186/s12891-023-06831-x. Full text in Research Archive Show summary

  Objective: To evaluate the efficacy of strength exercise or aerobic exercise compared to usual care on knee-related quality of life (QoL) and knee function at 4 months and 1 year in individuals with knee osteoarthritis. Methods: A three-arm randomized controlled trial (RCT) compared 12 weeks of strength exercise or aerobic exercise (stationary cycling) to usual care supervised by physiotherapists in primary care. We recruited 168 participants aged 35–70 years with symptomatic knee osteoarthritis. The primary outcome was The Knee Injury and Osteoarthritis Outcome Score (KOOS) QoL at 1 year. Secondary outcomes were self-reported function, pain, and self-efficacy, muscle strength and maximal oxygen uptake (VO2max) at 4 months and 1 year. Results: There were no differences between strength exercise and usual care on KOOS QoL (6.5, 95% CI -0.9 to 14), or for aerobic exercise and usual care (5.0, 95% CI -2.7 to 12.8), at 1 year. The two exercise groups showed better quadriceps muscle strength, and VO2max at 4 months, compared to usual care. Conclusion: This trial found no statistically significant effects of two exercise programs compared to usual care on KOOS QoL at 1 year in individuals with symptomatic and radiographic knee osteoarthritis, but an underpowered sample size may explain lack of efficacy between the intervention groups and the usual care group.

• Østerås, Nina; Aas, Eline; Moseng, Tuva; Bodegom-Vos, Leti van; Dziedzic, Krysia & Natvig, Bård [Show all 11 contributors for this article] (2023). Longer-term quality of care, effectiveness, and cost-effectiveness of implementing a model of care for osteoarthritis: A cluster-randomized controlled trial. Osteoarthritis and Cartilage. ISSN 1063-4584. 32(1), p. 108–119. doi: 10.1016/j.joca.2023.10.003. Full text in Research Archive Show summary

  Objective To assess the quality of care, effectiveness, and cost-effectiveness over 12 months after implementing a structured model of care for hip and knee osteoarthritis (OA) in primary healthcare as compared to usual care. Design In this pragmatic cluster-randomized, controlled trial with a stepped-wedge cohort design, we recruited 40 general practitioners (GPs), 37 physiotherapists (PTs), and 393 patients with symptomatic hip or knee OA from six municipalities (clusters) in Norway. The model included the delivery of a 3-hour patient education and 8–12 weeks individually tailored exercise programs, and interactive workshops for GPs and PTs. At 12 months, the patient-reported quality of care was assessed by the OsteoArthritis Quality Indicator questionnaire (16 items, pass rate 0–100%, 100%=best). Costs were obtained from patient-reported and national register data. Cost-effectiveness at the healthcare perspective was evaluated using incremental net monetary benefit (INMB). Results Of 393 patients, 109 were recruited during the control periods (control group) and 284 were recruited during interventions periods (intervention group). At 12 months the intervention group reported statistically significant higher quality of care compared to the control group (59% vs. 40%; mean difference: 17.6 (95% confidence interval [CI] 11.1, 24.0)). Cost-effectiveness analyses showed that the model of care resulted in quality-adjusted life-years gained and cost-savings compared to usual care with mean INMB €2020 (95% CI 611, 3492) over 12 months. Conclusions This study showed that implementing the model of care for OA in primary healthcare, improved quality of care and showed cost-effectiveness over 12 months compared to usual care.

• Ulstein, Svend; Årøen, Asbjørn; Engebretsen, Lars; Forssblad, Magnus & Røtterud, Jan Harald (2021). Effect of Concomitant Meniscal Lesions and Meniscal Surgery in ACL Reconstruction With 5-Year Follow-Up: A Nationwide Prospective Cohort Study From Norway and Sweden of 8408 Patients. Orthopaedic Journal of Sports Medicine (OJSM). 9(10), p. 1–9. doi: 10.1177/23259671211038375. Full text in Research Archive Show summary

  Background: Increased knowledge of the factors predicting outcome after anterior cruciate ligament reconstruction (ACLR) is needed. Purpose: To determine the effect of concomitant meniscal lesions, and the surgical management thereof, on patient-reported outcomes 5 years after ACLR. Study Design: Prospective cohort study; Level of evidence, 2. Methods: A total of 15,706 patients who underwent primary unilateral ACLR between 2005 and 2008 were enrolled prospectively and evaluated longitudinally. All patients were part of the Norwegian and Swedish national knee ligament registries. Outcomes at 5-year follow-up were evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS). A multivariable linear regression model was used to assess possible effects on prognosis, as measured by KOOS, of a concomitant meniscal lesion and its associated surgical treatment. Results: At a mean follow-up of 5.1 ± 0.2 years, KOOS data were available from 8408 patients: 4774 (57%) patients with no and 3634 (43%) patients with concomitant meniscal lesions (mean patient age, 33.8 ± 10.7 years). Patients with concomitant meniscal lesions reported equal crude mean scores compared with patients without meniscal lesions in all KOOS subscales 5 years after ACLR. The mean improvement in scores from preoperative to the 5-year follow-up was greater for patients with a concomitant meniscal lesion for the KOOS Pain, Activities of Daily Living (ADL), and Sport and Recreation subscales. In the adjusted regression analyses, using patients without concomitant meniscal lesions as the reference, neither no treatment nor resection or repair of medial meniscal lesions were significantly associated with KOOS scores 5 years after ACLR. Except for the ADL subscale, in which a repaired lateral meniscal lesion was associated with better outcome, no significant associations between any of the lateral meniscal lesion treatment categories and KOOS outcome at 5-year follow-up were identified. Conclusion: Concomitant meniscal lesions at the time of ACLR conferred no negative effects on patient-reported outcomes 5 years after ACLR. The improvement in selected KOOS subscales from preoperative to the 5-year follow-up was significantly greater for patients with concomitant meniscal lesions than for patients without such lesions.

• Moseng, Tuva; Dagfinrud, Hanne Solveig; Bodegom-Vos, Leti van; Dziedzic, Krysia; Hagen, Kåre Birger & Natvig, Bård [Show all 9 contributors for this article] (2020). Low adherence to exercise may have influenced the proportion of OMERACT-OARSI responders in an integrated osteoarthritis care model: secondary analyses from a cluster-randomised stepped-wedge trial. BMC Musculoskeletal Disorders. 21. doi: 10.1186/s12891-020-03235-z. Full text in Research Archive Show summary

  Background: To address the well-documented gap between hip and knee osteoarthritis (OA) treatment recommendations and current clinical practice, a structured model for integrated OA care was developed and evaluated in a stepped-wedge cluster-randomised controlled trial. The current study used secondary outcomes to evaluate clinically important response to treatment through the Outcome Measures in Rheumatology Clinical Trials clinical responder criteria (OMERACT-OARSI responder criteria) after 3 and 6 months between patients receiving the structured OA care model vs. usual care. Secondly, the study aimed to investigate if the proportion of responders in the intervention group was influenced by adherence to the exercise program inherent in the model. Methods: The study was conducted in primary healthcare in six Norwegian municipalities. General practitioners and physiotherapists received training in OA treatment recommendations and use of the structured model. The intervention group attended a physiotherapist-led OA education program and performed individually tailored exercises for 8–12 weeks. The control group received usual care. Patient-reported pain, function and global assessment of disease activity during the last week were evaluated using 11-point numeric rating scales (NRS 0–10). These scores were used to calculate the proportion of OMERACT-OARSI responders. Two-level mixed logistic regression models were fitted to investigate differences in responders between the intervention and control group. Results: Two hundred eighty-four intervention and 109 control group participants with hip and knee OA recruited from primary care in six Norwegian municipalities. In total 47% of the intervention and 35% of the control group participants were responders at 3 or 6 months combined; showing an uncertain between-group difference (ORadjusted 1.38 (95% CI 0.41, 4.67). In the intervention group, 184 participants completed the exercise programme (exercised ≥2 times/week for ≥8 weeks) and 55% of these were classified as responders. In contrast, 28% of the 86 non-completers were classified as responders. Conclusions: The difference in proportion of OMERACT-OARSI responders at 3 and 6 months between the intervention and control group was uncertain. In the intervention group, a larger proportion of responders were seen among the exercise completers compared to the non-completers.

• Pollmann, Christian Thomas; Dahl, Fredrik Andreas; Røtterud, Jan H; Gjertsen, Jan Erik & Årøen, Asbjørn (2020). Surgical site infection after hip fracture – mortality and risk factors: an observational cohort study of 1,709 patients. Acta Orthopaedica. ISSN 1745-3674. 91(3), p. 347–352. doi: 10.1080/17453674.2020.1717841. Full text in Research Archive Show summary

  Background and purpose — Surgical site infection (SSI) is a devastating complication of hip fracture surgery. We studied the contribution of early deep SSI to mortality after hip fracture surgery and the risk factors for deep SSI with emphasis on the duration of surgery. Patients and methods — 1,709 patients (884 hemi­arthroplasties, 825 sliding hip screws), operated from 2012 to 2015 at a single center were included. Data were obtained from the Norwegian Hip Fracture Register, the electronic hospital records, the Norwegian Surveillance System for Antibiotic Use and Hospital-Acquired Infections, and the Central Population Register. Results — The rate of early (≤ 30 days) deep SSI was 2.2% (38/1,709). Additionally, for hemiarthroplasties 7 delayed (> 30 days, ≤ 1 year) deep SSIs were reported. In patients with early deep SSI 90-day mortality tripled (42% vs. 14%, p

• Randsborg, Per-Henrik; Tajet, Jonas; Negård, henrik & Røtterud, Jan H (2020). Manipulation under Anesthesia for Stiffness of the Knee Joint after Total Knee Replacement. Arthroplasty Today. 6(3), p. 470–474. doi: 10.1016/j.artd.2020.05.019. Full text in Research Archive Show summary

  Background Stiffness of the knee joint is a feared complication after total knee replacement (TKR). An initial noninvasive treatment option is the manipulation of the knee under anesthesia (MUA). The purpose of this study is to evaluate the midterm result of the MUA for joint stiffness after primary TKR. Methods Patients treated with the MUA for knee stiffness after primary TKR surgery performed at Akershus University Hospital during 2014-2018 were invited to a follow-up clinic. The range of motion (ROM) of the knee joint was measured using a goniometer, and the patients reported the Lysholm score, Knee injury and Osteoarthritis Outcome Score, and Tegner score. In addition, any complications or reoperation after the MUA was noted. Results A total of 24 patients were identified in the journal system at the hospital. Twenty-three of these (17 women and 6 men) attended the designated follow-up on average 26 months (range [r], 16-35) after the MUA. The total ROM was 97° (r, 84°-116°) at the time of follow-up, compared with 70° (r, 50°-80°) before the MUA (P

• Pollmann, Christian Thomas; Røtterud, Jan H; Gjertsen, Jan-Erik; Dahl, Fredrik Andreas; Lenvik, Olav & Årøen, Asbjørn (2019). Fast track hip fracture care and mortality – an observational study of 2230 patients. BMC Musculoskeletal Disorders. 20. doi: 10.1186/s12891-019-2637-6. Full text in Research Archive Show summary

  Background: Hip fracture patients are frail and have a high mortality. We investigated whether the introduction of fast track care reduced the 30-day mortality after hip fractures. Methods: Fast track hip fracture care was established at our institution in October 2013. Data from the Norwegian Hip Fracture Register and electronic hospital records were merged for 2230 hip fracture patients operated in our department from January 2012 through December 2015. 1090 of these patients were operated before (conventional treatment group) and 1140 patients were operated after the introduction of fast track care (fast track group). Data were analysed by univariate analysis and binary logistic regression. Results: Mortality did not differ significantly between the conventional treatment group and the fast track group at 30 days (7.9% vs. 6.5%), 90 days (13.5% vs. 12.5%) and one year (22.8% vs. 22.8%). Median admission time and time to surgery were significantly shorter in the fast track group than in the conventional treatment group (1.1 h vs. 3.9 h and 23.6 h vs. 25.7 h, both p < 0.0001). The 30-day reoperation rate was significantly lower in the fast track group compared to the conventional treatment group (odds ratio = 0.35 (95% CI: 0.15–0.84), p = 0.019). A composite 30- day outcome (reoperation, surgical site infection and/or death) was significantly less frequent in the fast track group (8.1%) than in the conventional treatment group (10.7%) in unadjusted analysis (p = 0.006), but not after adjusting for age, gender, cognitive impairment and ASA score (odds ratio = 0.85 (95% CI: 0.63–1.16), p = 0.31, 8.0% missing). Reoperations within 1 year, surgical site infections, 30-day readmissions and length of hospital stay did not differ significantly between the conventional treatment group and the fast track group. Conclusions: Fast track hip fracture care is safe. However, we observed no statistically significant change in 30-day, 90-day or 1-year mortality after the introduction of fast track hip fracture care

• Randsborg, Per-Henrik; Kjennvold, Stian & Røtterud, Jan H (2019). Arthroscopic Fixation of Osteochondritis Dissecans of the Knee Using a Motorized Pick and Headless Compression Screws. Arthroscopy Techniques. p. e1–e6. doi: 10.1016/j.eats.2019.05.031. Full text in Research Archive
• Østerås, Nina; Moseng, Tuva; Bodegom-Vos, Leti van; Dziedzic, Krysia; Mdala, Ibrahimu & Natvig, Bård [Show all 12 contributors for this article] (2019). Implementing a structured model for osteoarthritis care in primary healthcare: A stepped-wedge cluster-randomised trial. PLoS Medicine. ISSN 1549-1277. 16(10). doi: 10.1371/journal.pmed.1002949. Full text in Research Archive Show summary

  Background To improve quality of care for patients with hip and knee osteoarthritis (OA), a structured model for integrated OA care was developed based on international recommendations. The objective of this study was to assess the effectiveness of this model in primary care. Methods and findings We conducted a cluster-randomised controlled trial with stepped-wedge cohort design in 6 Norwegian municipalities (clusters) between January 2015 and October 2017. The randomised order was concealed to the clusters until the time of crossover from the control to the intervention phase. The intervention was implementation of the SAMBA model, facilitated by interactive workshops for general practitioners and physiotherapists with an update on OA treatment recommendations. Patients in the intervention group attended a physiotherapist-led OA education and individually tailored exercise programme for 8–12 weeks. The primary outcome was patient-reported quality of care (OsteoArthritis Quality Indicator questionnaire; 0–100, 100 = optimal quality) at 6 months. Secondary outcomes included patient-reported referrals to physiotherapy, magnetic resonance imaging (MRI), and orthopaedic surgeon consultation; patients’ satisfaction with care; physical activity level; and proportion of patients who were overweight or obese (body mass index ≥ 25 kg/m2). In all, 40 of 80 general practitioners (mean age [SD] 50 [12] years, 42% females) and 37 of 64 physiotherapists (mean age [SD] 42 [8] years, 65% females) participated. They identified 531 patients, of which 393 patients (mean age [SD] 64 [10] years, 71% females) with symptomatic hip or knee OA were included. Among these, 109 patients were recruited during the control periods (control group), and 284 patients were recruited during interventions periods (intervention group). The patients in the intervention group reported significantly higher quality of care (score of 60 versus 41, mean difference 18.9; 95% CI 12.7, 25.1; p < 0.001) and higher satisfaction with OA care (odds ratio [OR] 12.1; 95% CI 6.44, 22.72; p < 0.001) compared to patients in the control group. The increase in quality of care was close to, but below, the pre-specified minimal important change. In the intervention group, a higher proportion was referred to physiotherapy (OR 2.5; 95% CI 1.08, 5.73; p = 0.03), a higher proportion fulfilled physical activity recommendations (OR 9.3; 95% CI 2.87, 30.37; p < 0.001), and a lower proportion was referred to an orthopaedic surgeon (OR 0.3; 95% CI 0.08, 0.80; p = 0.02), as compared to the control group. There were no significant group differences regarding referral to MRI (OR 0.6; 95% CI 0.13, 2.38; p = 0.42) and proportion of patients who were overweight or obese (OR 1.3; 95% CI 0.70, 2.51; p = 0.34). Study limitations include the imbalance in patient group size, which may have been due to an increased attention to OA patients among the health professionals during the intervention phase, and a potential recruitment bias as the patient participants were identified by their health professionals. Conclusions In this study, a structured model in primary care resulted in higher quality of OA care as compared to usual care. Future studies should explore ways to implement the structured model for integrated OA care on a larger scale.

• Owesen, Christian; Røtterud, Jan H; Engebretsen, Lars & Årøen, Asbjørn (2018). Effect of Activity at Time of Injury and Concomitant Ligament Injuries on Patient- Reported Outcome After Posterior Cruciate Ligament Reconstruction. Orthopaedic Journal of Sports Medicine (OJSM). 6(12). doi: 10.1177/2325967118817297. Full text in Research Archive Show summary

  Background: The outcomes after posterior cruciate ligament reconstruction (PCLR) have been shown to be inferior to those of anterior cruciate ligament reconstruction. There is a lack of knowledge regarding prognostic factors of PCLR outcomes. Purpose: To explore the effect of injury mechanism and concomitant ligament injuries on patient-reported outcomes at 2-year follow-up after PCLR. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 373 patients who underwent primary PCLR and who were registered in the Norwegian Knee Ligament Registry were included. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used as the patient-reported outcome measure. At 2-year follow-up, 252 patients (68%) had completed the KOOS. Multiple regression analysis was used to evaluate the effects of injury activity and multiligament injuries on the KOOS outcomes. Results: In the adjusted and unadjusted regression analyses, patients injured during sports reported significantly better outcome at 2-year follow-up after PCLR than patients injured during other activities (P < .001) according to all KOOS subscales. Adjusted analysis was as follows for the KOOS subscales: Symptoms (regression coefficient [β], 7.0; 95% CI, 1.9-12.2), Pain (β, 13.4; 95% CI, 8.0-18.9), Activities of Daily Living (β, 12.6; 95% CI, 7.1-18.1), Sport/Recreation (β, 15.3; 95% CI, 8.0-22.5), and Quality of Life (β, 13.5; 95% CI, 7.1-20.0). In the unadjusted analysis, patients with isolated PCL injuries reported higher scores in the Sport/Recreation subscale (β, –7.9; 95% CI, –15.5 to –0.3). The difference was not significant in the adjusted analysis. No other significant differences in KOOS outcomes were found between isolated and multiligament injuries. Conclusion: Patients injured in sports reported better outcomes at 2 years after PCLR as compared with patients injured in other activities. Multiligament injuries involving the PCL do not seem to predict a worse outcome than for isolated PCL injuries.

• Ulstein, Svend; Årøen, Asbjørn; Engebretsen, Lars; Forssblad, Magnus; Lygre, Stein Håkon Låstad & Røtterud, Jan H (2018). Effect of concomitant cartilage lesions on patient-reported outcomes after anterior cruciate ligament reconstruction. A Nationwide chohort study from Norway and Sweden of 8470 patients With 5 year follow-up. Orthopaedic Journal of Sports Medicine (OJSM). 6:2325967118786219(7), p. 1–7. doi: 10.1177/2325967118786219. Full text in Research Archive Show summary

  All patients who underwent unilateral primary ACLR registered in the Norwegian and Swedish National Knee Ligament Registries from 2005 to 2008 (n = 15,783) were included in the study. At 5-year follow-up, 8470 (54%) patients completed the Knee injury and Osteoarthritis Outcome Score (KOOS). Multivariable linear regression models were used to estimate the effect of concomitant partial-thickness and full-thickness cartilage lesions on patient-reported outcomes (KOOS) 5 years after ACLR. Compared with no concomitant cartilage lesions, both partial-thickness and full-thickness cartilage lesions were indicators of statistically significant adverse effects on the KOOS in the adjusted regression analysis at 5-year follow-up after ACLR. Conclusion: ACL-injured patients with concomitant cartilage lesions reported worse outcomes and less improvement than those without cartilage lesions 5 years after ACLR.

• Ulstein, Svend; Årøen, Asbjørn; Engebretsen, Lars; Forssblad, Magnus; Lygre, Stein Håkon Låstad & Røtterud, Jan H (2018). A Controlled Comparison of Microfracture, Debridement, and No Treatment of Concomitant Full-Thickness Cartilage Lesions in Anterior Cruciate Ligament-Reconstructed Knees: A Nationwide Prospective Cohort Study From Norway and Sweden of 368 Patients With 5-Year Follow-up. Orthopaedic Journal of Sports Medicine (OJSM). 6(8). doi: 10.1177/2325967118787767. Full text in Research Archive Show summary

  Background: The effect of microfracture (MF) or surgical debridement of concomitant full-thickness cartilage lesions in anterior cruciate ligament–reconstructed knees on patient-reported outcomes remains to be determined. Purpose: To evaluate the effect of debridement or MF compared with no surgical treatment of concomitant full-thickness cartilage lesions on patient-reported outcomes 5 years after anterior cruciate ligament reconstruction (ACLR). Study Design: Cohort study; Level of evidence, 2. Methods: Included in this study were 644 patients who were registered in the Norwegian and the Swedish National Knee Ligament Registries from 2005 to 2008 as having undergone unilateral primary ACLR and having a concomitant full-thickness cartilage lesion (International Cartilage Repair Society [ICRS] grades 3-4). Of these patients, 129 were treated with debridement, 164 were treated with MF, and 351 received no surgical treatment simultaneously with ACLR. At 5-year follow-up, 368 (57%) patients completed results on the Knee injury and Osteoarthritis Outcome Score (KOOS).Multivariable linear regression was used to estimate the effect of surgical debridement or MF of concomitant full-thickness cartilage lesions on patient-reported outcomes 5 years after ACLR. Results: Compared with no surgical treatment, there were no unadjusted or adjusted effects of debridement or MF of concomitant full-thickness cartilage lesions on KOOS scores at 5-year follow-up. Conclusion: Compared with leaving concomitant full-thickness cartilage lesions untreated at the time of ACLR, debridement and MF showed no effect on patient-reported outcomes 5 years after surgery.

• Randsborg, Per-Henrik & Røtterud, Jan H (2017). No difference in the level of physical activity between children who have or have never sustained a fracture. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 27(12), p. 1801–1805. doi: 10.1111/sms.12787. Full text in Research Archive
• Røtterud, Jan H; Sivertsen, Einar; Forssblad, Magnus; Engebretsen, Lars & Årøen, Asbjørn (2016). Effect on Patient-Reported Outcomes of Debridement or Microfracture of Concomitant Full-Thickness Cartilage Lesions in Anterior Cruciate Ligament-Reconstructed Knees: A Nationwide Cohort Study from Norway and Sweden of 357 Patients with 2-Year Follow-up. American Journal of Sports Medicine. ISSN 0363-5465. 44(2), p. 337–344. doi: 10.1177/0363546515617468. Full text in Research Archive Show summary

  Background: The treatment of concomitant cartilage lesions in anterior cruciate ligament (ACL)–injured knees is debatable. Purpose: To evaluate the effect of debridement or microfracture (MF) compared with no treatment of concomitant full-thickness (International Cartilage Repair Society [ICRS] grades 3-4) cartilage lesions on patient-reported outcomes after ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Six hundred forty-four patients who underwent primary unilateral ACL reconstruction and had a concomitant fullthickness cartilage lesion treated simultaneously by debridement (n = 129) or MF (n = 164), or underwent no treatment (n = 351) of the cartilage lesion, registered in the Norwegian and Swedish National Knee Ligament Registries from 2005 to 2008 were included. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was used to measure patient-reported outcomes. At a mean follow-up of 2.1 6 0.2 years after surgery, 357 (55%) patients completed the KOOS. Linear regression analyses were used to evaluate the effect of debridement or MF on the KOOS. Results: No significant effects of debridement were detected in the unadjusted or adjusted regression analyses on any of the KOOS subscales at 2-year follow-up. The MF treatment of the cartilage lesions had significant negative effects at 2-year follow-up on the KOOS Sport and Recreation (Sport/Rec) (regression coefficient [b] = –8.9; 95% confidence interval [CI], –15.1 to –1.5) and Knee-Related Quality of Life (QoL) (b = –8.1; 95% CI, –14.1 to –2.1) subscales in the unadjusted analyses. When adjusting for confounders, MF had significant negative effects on the same KOOS subscales of Sport/Rec (b = –8.6; 95% CI, –16.4 to –0.7) and QoL (b = –7.2; 95% CI, –13.6 to –0.8). For the remaining KOOS subscales of Pain, Symptoms, and Activities of Daily Living, there were no significant unadjusted or adjusted effects of MF. Conclusion: MF of concomitant full-thickness cartilage lesions showed adverse effects on patient-reported outcomes at 2-year follow-up after ACL reconstruction. Debridement of concomitant full-thickness cartilage lesions showed neither positive nor negative effects on patient-reported outcomes at 2-year follow-up after ACL reconstruction.

• Ulstein, Svend; Bredland, Karin; Årøen, Asbjørn; Engebretsen, Lars & Røtterud, Jan H (2016). No negative effect on patient-reported outcome of concomitant cartilage lesions 5–9 years after ACL reconstruction. Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 24, p. 340–341. doi: 10.1007/s00167-016-4163-5. Full text in Research Archive Show summary

  Purpose: To compare patient-reported outcome 5–9 years after anterior cruciate ligament (ACL) reconstruction in patients with and without a concomitant full-thickness [International Cartilage Repair Society (ICRS) grade 3–4] cartilage lesion. Methods: This is a prospective follow-up of a cohort of 89 patients that were identified in the Norwegian National Knee Ligament Registry and included in the current study in 2007, consisting of 30 primary ACL-reconstructed patients with a concomitant, isolated full-thickness cartilage lesion (ICRS grade 3 and 4) and 59 matched controls without cartilage lesions (ICRS grade 1–4). At a median follow-up of 6.3 years (range 4.9–9.1) after ACL reconstruction, 74 (84 %) patients completed the Knee Injury and Osteoarthritis Outcome Score (KOOS), which was used as the main outcome measure. Secondary outcomes included radiographic evaluation according to the Kellgren– Lawrence criteria of knee osteoarthritis (OA). Results At follow-up, 5–9 years after ACL reconstruction, no statistically significant differences in KOOS were detected between patients with a concomitant full-thickness cartilage lesion and patients without concomitant cartilage lesions. Radiographic knee OA of the affected knee,defined as Kellgren and Lawrence ≥2, was significantly more frequent in subjects without a concomitant cartilage lesion (p = 0.016). Conclusion: ACL reconstruction performed in patients with an isolated concomitant full-thickness cartilage lesion restored patient-reported knee function to the same level as ACL reconstruction performed in patients without concomitant cartilage lesions, 5–9 years after surgery. This should be considered in the preoperative information given to patients with such combined injuries, in terms of the expected outcome after ACL reconstruction and in the counselling and decision-making on the subject of surgical treatment of the concomitant cartilage lesion. Level of evidence: Prognostic; prospective cohort study, Level I.

• Årøen, Asbjørn; Brøgger, Helga Marie; Røtterud, Jan H; Sivertsen, Einar Andreas; Engebretsen, Lars & Risberg, May Arna (2016). Evaluation of focal cartilage lesions of the knee using MRI T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC). BMC Musculoskeletal Disorders. 17(1). doi: 10.1186/s12891-016-0941-y. Full text in Research Archive Show summary

  Background Assessment of degenerative changes of the cartilage is important in knee cartilage repair surgery. Magnetic Resonance Imaging (MRI) T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) are able to detect early degenerative changes. The hypothesis of the study was that cartilage surrounding a focal cartilage lesion in the knee does not possess degenerative changes. Methods Twenty-eight consecutive patients included in a randomized controlled trial on cartilage repair were evaluated using MRI T2 mapping and dGEMRIC before cartilage treatment was initiated. Inclusion was based on disabling knee problems (Lysholm score of ≤ 75) due to an arthroscopically verified focal femoral condyle cartilage lesion. Furthermore, no major malalignments or knee ligament injuries were accepted. Mean patient age was 33 ± 9.6 years, and the mean duration of knee symptoms was 49 ± 60 months. The MRI T2 mapping and the dGEMRIC measurements were performed at three standardized regions of interest (ROIs) at the medial and lateral femoral condyle, avoiding the cartilage lesion Results The MRI T2 mapping of the cartilage did not demonstrate significant differences between condyles with or without cartilage lesions. The dGEMRIC results did not show significantly lower values of the affected condyle compared with the opposite condyle and the contra-lateral knee in any of the ROIs. The intraclass correlation coefficient (ICC) of the dGEMRIC readings was 0.882. Conclusion The MRI T2 mapping and the dGEMRIC confirmed the arthroscopic findings that normal articular cartilage surrounded the cartilage lesion, reflecting normal variation in articular cartilage quality. Study identifier NCT00885729 , registered April 17 2009.

• Østerås, Nina; Bodegom-Vos, Leti van; Dziedzic, Krysia; Moseng, Tuva; Aas, Eline & Andreassen, Øyvor [Show all 12 contributors for this article] (2015). Implementing international osteoarthritis treatment guidelines in primary Health care: study protocol for the SAMBA stepped wedge cluster randomized controlled trial. Implementation Science. 10(1). doi: 10.1186/s13012-015-0353-7. Full text in Research Archive Show summary

  Background Previous research indicates that people with osteoarthritis (OA) are not receiving the recommended and optimal treatment. Based on international treatment recommendations for hip and knee OA and previous research, the SAMBA model for integrated OA care in Norwegian primary health care has been developed. The model includes physiotherapist (PT) led patient OA education sessions and an exercise programme lasting 8–12 weeks. This study aims to assess the effectiveness, feasibility, and costs of a tailored strategy to implement the SAMBA model. Methods/design A cluster randomized controlled trial with stepped wedge design including an effect, process, and cost evaluation will be conducted in six municipalities (clusters) in Norway. The municipalities will be randomized for time of crossover from current usual care to the implementation of the SAMBA model by a tailored strategy. The tailored strategy includes interactive workshops for general practitioners (GPs) and PTs in primary care covering the SAMBA model for integrated OA care, educational material, educational outreach visits, feedback, and reminder material. Outcomes will be measured at the patient, GP, and PT levels using self-report, semi-structured interviews, and register based data. The primary outcome measure is patient-reported quality of care (OsteoArthritis Quality Indicator questionnaire) at 6-month follow-up. Secondary outcomes include referrals to PT, imaging, and referrals to the orthopaedic surgeon as well as participants’ treatment satisfaction, symptoms, physical activity level, body weight, and self-reported and measured lower limb function. The actual exposure to the tailor made implementation strategy and user experiences will be measured in a process evaluation. In the economic evaluation, the difference in costs of usual OA care and the SAMBA model for integrated OA care will be compared with the difference in health outcomes and reported by the incremental cost-effectiveness ratio (ICER). Discussion The results from the present study will add to the current knowledge on tailored strategies, which aims to improve the uptake of evidence-based OA care recommendations and improve the quality of OA care in primary health care. The new knowledge can be used in national and international initiatives designed to improve the quality of OA care.

• Ulstein, Svend; Årøen, Asbjørn; Røtterud, Jan H; Løken, Sverre Bertrand; Engebretsen, Lars & Heir, Stig (2014). Microfracture technique versus osteochondral autologous transplantation mosaicplasty in patients with articular chondral lesions of the knee: a prospective randomized trial with long-term follow-up. Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 22(6), p. 1207–1215. doi: 10.1007/s00167-014-2843-6. Full text in Research Archive Show summary

  Purpose: To compare long-term functional and radiological outcome following microfracture technique (MF) versus osteochondral autologous transplantation (OAT) mosaicplasty for treating focal chondral lesions of the knee. Methods: Twenty-five patients (mean age 32.3 years, SD 7.7) with a full-thickness (International Cartilage Repair Society grade 3 or 4) chondral lesion of the articulating surface of the femur were randomized to either MF (n = 11) or OAT mosaicplasty (n = 14). At a median follow-up of 9.8 years (range 4.9–11.4), the patients were evaluated using Lysholm score (n = 25), Knee Injury and Osteoarthritis Outcome Score (KOOS, n = 25), isokinetic quadriceps measurement and hamstring strength measurement (n = 22) and standing radiographs (n = 23). Results: There were no significant differences in Lysholm score, KOOS, isokinetic muscle strength or radiographic osteoarthritis between MF-treated patients and OAT mosaicplasty-treated patients at follow-up. Mean Lysholm score at follow-up was 69.7 [95 % confidence interval (CI), 55.1–84.4] for the MF group and 62.6 (95 % CI, 52.6–72.6) for the OAT mosaicplasty group. Conclusion: At long-term follow-up, there were no significant differences between patients treated with MF and patients treated with OAT mosaicplasty in patient-reported outcomes, muscle strength or radiological outcome. Level of evidence: Therapeutic study, Level II.

• Randsborg, Per-Henrik; Fuglesang, Hendrik Frølich; Røtterud, Jan H; Hammer, Ola-Lars & Sivertsen, Einar (2014). Long-term Patient-reported Outcome After Fractures of the Clavicle in Patients Aged 10 to 18 Years. Journal of Pediatric Orthopaedics. ISSN 0271-6798. 34(4), p. 393–399. doi: 10.1097/BPO.0000000000000082. Full text in Research Archive
• Ulstein, Svend; Bredland, K; Årøen, Asbjørn; Engebretsen, Lars & Røtterud, Jan H (2014). Ingen negativ effekt av fulltykkelse bruskskade hos fremre korsbånd rekonstruerte pasienter ved 5-9 års oppfølging. In Drogset, Jon Olav (Eds.), Høstmøteboken : vitenskapelig program og abstrakter 2014. Norsk ortopedisk forening. p. 213–213. Full text in Research Archive
• Røtterud, Jan H; Reinholt, Finn P.; Beckstrøm, Karen Johanne; Risberg, May Arna & Årøen, Asbjørn (2014). Relationship between CTX-II and patient characteristics, patient-reported outcome, muscle strength, and rehabilitation in patients with a focal cartilage lesion of the knee: A prospective exploratory cohort study of 48 patients. BMC Musculoskeletal Disorders. 15(1). doi: 10.1186/1471-2474-15-99. Full text in Research Archive Show summary

  Background: C-telopeptide fragments of type II collagen (CTX-II) are created during articular cartilage breakdown and CTX-II is considered useful as a biomarker of osteoarthritis. The primary objective of the present study was to explore the relationship between urinary CTX-II concentration and patient characteristics, patient-reported outcome, muscle strength, and rehabilitation in patients with isolated focal knee cartilage lesions. Furthermore, the secondary objective was to examine differences in urinary CTX-II concentration between patients with focal cartilage lesions and healthy controls. Methods: 48 patients (mean age 33.4 years, standard deviation 9.0) with a focal full-thickness (International Cartilage Repair Society grade 3 or 4) cartilage lesion on the medial or lateral femoral condyle were included. After baseline assessments, the patients completed a 3-month rehabilitation program and 44 patients attended the 3 month follow-up. Baseline and follow-up assessments consisted of urinary CTX-II, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and isokinetic quadriceps and hamstring muscle strength measurements. CTX-II was also analysed in urine samples from 6 healthy individuals, serving as normal controls. Correlations were classified as very weak (correlation coefficient [r] < 0.20), weak (r = 0.20 – 0.39), moderate (r = 0.40 – 0.59), strong (r = 0.60 – 0.79), and very strong (r > 0.80). Results: Except for age and quadriceps strength, no significant correlations were found between CTX-II concentrations and baseline characteristics, KOOS, or muscle strength. Except for age, all correlations were considered as weak or very weak. The patients with a focal cartilage lesion had significantly higher mean CTX-II concentration than the healthy control individuals both at baseline (p = 0.001) and at follow-up (p = 0.001). The mean CTX-II concentration tended to decrease during rehabilitation, but the reduction was not significant (p = 0.076). Conclusions: The current exploratory study demonstrated that patients with a focal cartilage lesion of the knee had higher concentrations of urinary CTX-II than healthy individuals. In addition, CTX-II concentration tended to decrease during rehabilitation.

• Randsborg, Per-Henrik; Fuglesang, Hendrik Frølich; Røtterud, Jan H & Sivertsen, Einar (2013). Selvrapporterte resultater 4,7 år etter kravebeinsbrudd hos pasienter i alderen 10-18 år. In Fjeldsgaard, Knut (Eds.), Høstmøteboken : vitenskapelig program og abstrakter - 2013. Norsk ortopedisk forening. p. 190–190. Full text in Research Archive
• Wondrasch, Barbara; Årøen, Asbjørn; Røtterud, Jan H; Høysveen, Turid; Bølstad, Kristin & Risberg, May Arna (2013). The Feasibility of a 3-Month Active Rehabilitation Program for Patients With Knee Full-Thickness Articular Cartilage Lesions: The Oslo Cartilage Active Rehabilitation and Education Study. Journal of Orthopaedic and Sports Physical Therapy. ISSN 0190-6011. 43(5), p. 310–324. doi: 10.2519/jospt.2013.4354. Full text in Research Archive Show summary

  Study Design: Case series. Objectives: To evaluate the feasibility of an active rehabilitation program for patients with knee full-thickness articular cartilage lesions. Background: No studies have yet evaluated the effect of active rehabilitation in patients with knee full-thickness articular cartilage lesions or compared the effects of active rehabilitation to those of surgical interventions. As an initial step, the feasibility of such a program needs to be described. Methods: Forty-eight patients with a knee full-thickness articular cartilage lesion and a Lysholm score below 75 participated in a 3-month active rehabilitation program consisting of cardiovascular training, knee and hip progressive resistance training, and neuromuscular training. Feasibility was determined by monitoring adherence to the program, clinical changes in knee function, load progression, and adverse events. Patients were tested before and after completing the rehabilitation program by using patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee Subjective Knee Evaluation Form 2000) and isokinetic muscle strength and hop tests. To monitor adherence, load progression, and adverse events, patients responded to an online survey and kept training diaries. Results: The average adherence rate to the rehabilitation program was 83%. Four patients (9%) showed adverse events, as they could not perform the exercises due to pain and effusion. Significant and clinically meaningful improvement was found, based on changes on the International Knee Documentation Committee Subjective Knee Evaluation Form 2000, the Knee injury and Osteoarthritis Outcome Score quality of life subscale, isokinetic muscle strength, and hop performance (P<.05), with small to large effect sizes (standardized response mean, 0.3–1.22). Conclusion: The combination of a high adherence rate, clinically meaningful changes, and positive load progression and the occurrence of only a few adverse events support the potential usefulness of this program for patients with knee full-thickness cartilage lesions. This study was registered with the public trial registry Clinical Trials.gov (NCT00885729).

• Røtterud, Jan H; Sivertsen, Einar; Forssblad, Magnus; Engebretsen, Lars & Årøen, Asbjørn (2013). Effect of Meniscal and Focal Cartilage Lesions on Patient-Reported Outcome After Anterior Cruciate Ligament Reconstruction : A Nationwide Cohort Study From Norway and Sweden of 8476 Patients With 2-Year Follow-up. American Journal of Sports Medicine. ISSN 0363-5465. 41(3), p. 535–543. doi: 10.1177/0363546512473571. Full text in Research Archive Show summary

  Background: The effect of concomitant intra-articular injury on patient-reported outcome after anterior cruciate ligament (ACL) reconstruction is debated. Purpose: To evaluate the effect of meniscal and articular cartilage lesions on patient-reported outcome 2 years after ACL reconstruction. Study Design: Cohort study (prognosis); Level of evidence, 2. Methods: The study included all patients with primary, unilateral ACL reconstruction registered in the Norwegian and the Swedish National Knee Ligament Registry from 2005 through 2008 who had completed the Knee Injury and Osteoarthritis Outcome Score (KOOS) Knee-Related Quality of Life subscale at a 2-year follow-up (mean 6 SD, 2.1 6 0.2 years) after surgery (n = 8476). Multiple linear regression analyses were used to evaluate the associations between each KOOS subscale (Pain, Other Symptoms, Activities of Daily Living, Sport and Recreation Function, Knee-Related Quality of Life) as the measure for patient-reported outcome and meniscal and cartilage lesions. Results: A total of 3674 (43%) patients had meniscal lesion(s), 1671 (20%) had partial-thickness (International Cartilage Repair Society [ICRS] grades 1-2) cartilage lesion(s), and 551 (7%) had full-thickness (ICRS grades 3-4) cartilage lesion(s). Multiple linear regression analyses detected no significant associations between meniscal lesions or partial-thickness cartilage lesions and the scores in any of the KOOS subscales at the 2-year follow-up. Full-thickness cartilage lesions were significantly associated with decreased scores in all of the KOOS subscales. Conclusion: Patients with concomitant full-thickness cartilage lesions reported worse outcome in all of the KOOS subscales compared with patients without cartilage lesions 2 years after ACL reconstruction. Meniscal lesions and partial-thickness cartilage lesions did not impair patient-reported outcome 2 years after ACL reconstruction.

• Årøen, Asbjørn; Røtterud, Jan H & Sivertsen, Einar (2013). Agreement in Arthroscopic and Arthrotomy Assessment of Full-Thickness Articular Cartilage Lesions of the Knee in a Clinical Setting in 33 Consecutive Patients. Cartilage. ISSN 1947-6035. doi: 10.1177/1947603513483546. Full text in Research Archive Show summary

  Objective: To evaluate the accuracy of arthroscopic measurement of full-thickness (International Cartilage Repair Society grades 3-4) cartilage lesions of the knee. Design: In 33 consecutive arthroscopically evaluated cartilage lesion knees the lesion size was routinely estimated. At the final treatment, a knee arthrotomy was performed, and the lesion was reestimated. The 2 estimates were then compared by paired t test and the area estimated by knee arthrotomy was used as the gold standard. Results: The mean area of the cartilage lesion estimated by arthroscopic surgery was 3.5 cm2 (standard deviation [SD] = 1.7) whereas in the open surgery the mean area was 3.2 cm2 (SD = 1.5). The mean difference was 0.3 cm2, indicating a tendency toward overestimation by the arthroscopic evaluation, but the difference was not significant (P = 0.09). Additional MRI assessment of the area demonstrated a mean area of 2.3 cm2 (SD = 1.6). This underestimated the size of the lesion by 1.2 cm2 (SD = 0.8; P = 0.015). Conclusion: Knee arthroscopic examination estimated a cartilage fullthickness lesion with an error of less than 25 % in the majority of the patients.

• Røtterud, Jan H; Sivertsen, EA; Forssblad, M; Engebretsen, Lars & Årøen, Asbjørn (2012). Effekt av menisk- og bruskskade på pasientrapportert resultat etter rekunstruksjon av fremre korsbånd. In Ukjent, Person (Eds.), Høstmøteboken 2012 - Høstmøtet Norsk ortopedisk forening. Norsk ortopedisk forening. p. 224–224. Full text in Research Archive
• Ulstein, S; Årøen, Asbjørn; Røtterud, Jan H; Løken, Sverre Bertrand; Engebretsen, Lars & Heir, Stig (2012). Mikrofraktur teknikk vs mosaikkplastikk for fokale bruskskader i kne, en prospektiv randomisert multisenterstudie med 5-11 års oppfølging. In Ukjent, Person (Eds.), Høstmøteboken 2012 - Høstmøtet Norsk ortopedisk forening. Norsk ortopedisk forening. p. 43–43. Full text in Research Archive
• Røtterud, Jan H; Risberg, May Arna; Engebretsen, Lars & Årøen, Asbjørn (2012). Patients with focal full-thickness cartilage lesions benefit less from ACL reconstruction at 2-5 years follow-up. Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 20(8), p. 1533–1539. doi: 10.1007/s00167-011-1739-y. Full text in Research Archive
• Røtterud, Jan H; Sivertsen, Einar; Forssblad, Magnus; Engebretsen, Lars & Årøen, Asbjørn (2011). Effect of Gender and Sports on the Risk of Full-Thickness Articular Cartilage Lesions in Anterior Cruciate Ligament–Injured Knees: A Nationwide Cohort Study From Sweden and Norway of 15 783 Patients. American Journal of Sports Medicine. ISSN 0363-5465. 39(7), p. 1387–1394. doi: 10.1177/0363546510397813. Full text in Research Archive Show summary

  Background: The presence of an articular cartilage lesion in anterior cruciate ligament–injured knees is considered a predictor of osteoarthritis. Purpose: This study was undertaken to evaluate risk factors for full-thickness articular cartilage lesions in anterior cruciate ligament–injured knees, in particular the role of gender and the sport causing the initial injury. Study Design: Cohort study (prognosis); Level of evidence, 2. Methods: Primary unilateral anterior cruciate ligament reconstructions prospectively registered in the Swedish and the Norwegian National Knee Ligament Registry during 2005 through 2008 were included (N = 15 783). Logistic regression analyses were used to evaluate risk factors for cartilage lesions. Results: A total of 1012 patients (6.4%) had full-thickness cartilage lesions. The median time from injury to surgery was 9 months (range, 0 days-521 months). Male patients had an increased odds of full-thickness cartilage lesions compared with females (odds ratio = 1.22; 95% confidence interval, 1.04-1.42). In males, team handball had an increase in the odds of full-thickness cartilage lesions compared with soccer (odds ratio = 2.36; 95% confidence interval, 1.33-4.19). Among female patients, no sport investigated showed a significant decrease or increase in the odds of full-thickness cartilage lesions. The odds of a full-thickness cartilage lesion increased by 1.006 (95% confidence interval, 1.005-1.008) for each month elapsed from time of injury until anterior cruciate ligament reconstruction when all patients were considered, while time from injury to surgery did not affect the odds significantly in those patients reconstructed within 1 year of injury (odds ratio = 0.98; 95% confidence interval, 0.95-1.02). Previous surgery increased the odds of having a full-thickness cartilage lesion (odds ratio = 1.40; 95% confidence interval, 1.21-1.63). One year of increasing patient age also increased the odds (odds ratio = 1.05; 95% confidence interval, 1.05-1.06). Conclusion: Male gender is associated with an increased risk of full-thickness articular cartilage lesions in anterior cruciate ligament–injured knees. Male team handball players had an increased risk of full-thickness lesions. No other sports investigated were found to have significant effect on the risk in either gender. Furthermore, age, previous surgery, and time from injury to surgery exceeding 12 months are risk factors for full-thickness cartilage lesions.

• Heir, Stig; Nerhus, Tor Kjetil; Røtterud, Jan H; Løken, Sverre Bertrand; Ekeland, Arne Erling & Engebretsen, Lars [Show all 7 contributors for this article] (2010). Focal Cartilage Defects in the Knee Impair Quality of Life as Much as Severe Osteoarthritis A Comparison of Knee Injury and Osteoarthritis Outcome Score in 4 Patient Categories Scheduled for Knee Surgery. American Journal of Sports Medicine. ISSN 0363-5465. 38(2), p. 231–237. doi: 10.1177/0363546509352157. Full text in Research Archive

View all works in NVA

• Øiestad, Britt Elin; Årøen, Asbjørn; Røtterud, Jan H; Østerås, Nina; Jarstad, Even & Grotle, Margreth [Show all 7 contributors for this article] (2022). Effekt av to ulike treningsprogram for pasienter med symptomatisk kneartrose. En klinisk randomisert kontrollert studie. Full text in Research Archive
• Randsborg, Per-Henrik; Tajet, Jonas; Negård, Henrik & Røtterud, Jan H (2019). Manipulasjon under anestesi (MUA) for stivhet etter kneprotese. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Forssblad, Magnus; Engebretsen, Lars & Røtterud, Jan H (2018). Effect of concomitant cartilage lesions on patient-reported outcome after ACL-reconstruction - a nationwide cohort study from Norway and Sweden of 8470 patients with 5-year follow-up. Orthopaedic Journal of Sports Medicine (OJSM). 6(7). doi: 10.1177/2325967118S00058. Full text in Research Archive
• Østerås, Nina; Hagen, Kåre Birger; Moseng, Tuva; Andreassen, Øyvor; Hansen, Jorun Nygren & Natvig, Bård [Show all 8 contributors for this article] (2018). Samhandling for bedre artrosebehandling (SAMBA) - forskning i primærhelsetjenesten. Full text in Research Archive
• Moseng, Tuva; Dagfinrud, Hanne; Andreassen, Øyvor; Dziedzic, Krysia; Hagen, Kåre Birger & Hansen, Jorun Nygren [Show all 13 contributors for this article] (2018). Implementing international osteoarthritis guidelines in primary care: results on symptom-related outcomes in secondary analyses from a randomised controlled study. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Forssblad, Magnus; Engebretsen, Lars & Røtterud, Jan H (2018). Effect of concomitant cartilage lesions on patient-reported outcome after ACL-reconstruction – a nationwide cohort study from Norway and Sweden of 8,470 patients with 5-Year follow-up. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Forssblad, Magnus; Engebretsen, Lars; Lygre, Stein Håkon Låstad & Røtterud, Jan H (2017). Effekt av mikrofraktur eller debridement av ledsagende dyp bruskskade ved ACL-rekonstruksjon - en landsomfattende kohortestudie fra Norge og Sverige med 368 pasienter med 5-års oppfølging. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Forssblad, Magnus; Engebretsen, Lars; Lygre, Stein Håkon Låstad & Røtterud, Jan H (2017). ACL-rekonstruksjon i knær med ledsagende bruskskade - en landsomfattende kohortestudie fra Norge og Sverige med 8470 pasienter med 5 års oppfølging. Full text in Research Archive
• Randsborg, Per-Henrik & Røtterud, Jan H (2017). Degenerative meniskrupturer bør ikke opereres :. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 137, p. 258–258. doi: 10.4045/tidsskr.16.1028. Full text in Research Archive
• Ulstein, Svend; Bredland, Karin; Årøen, Asbjørn; Engebretsen, Lars & Røtterud, Jan H (2016). No negative effect on patient-reported outcome of cartilage lesions 5-9 years after ACL-reconstruction. Full text in Research Archive
• Ulstein, Svend; Bredland, Karin; Årøen, Asbjørn; Engebretsen, Lars & Røtterud, Jan H (2016). No negative effect on patient-reported outcome of cartilage lesions 5-9 years after ACL-reconstruction. Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 24, p. S340–S341. Full text in Research Archive
• Røtterud, Jan H; Sivertsen, Einar; Forssblad, M; Engebretsen, Lars & Årøen, Asbjørn (2015). Effect on patient-reported outcome of debridement or microfracture of concomitant full-thickness cartilage lesions in anterior cruciate ligament reconstructed knees: a nationwide cohort study from Norway and Sweden of 357 pasients with 2-year-follow-up. Full text in Research Archive
• Røtterud, Jan H (2015). Focal cartilage lesions in anterior cruciate ligament-injured knees – Incidence, risk, prognosis and treatment. Full text in Research Archive
• Røtterud, Jan H (2015). Meniskkirurgi hos middelaldrende - finnes det evidens for kirurgi eller ikke-kirurgi? Full text in Research Archive
• Røtterud, Jan H (2015). Hva gjør vi med en samtidig bruskskade? Full text in Research Archive
• Årøen, Asbjørn; Brøgger, Helga Marie; Røtterud, Jan H; Sivertsen, Einar; Engebretsen, Lars & Risberg, May Arna (2014). Evaluation of surrounding articular cartilage in 28 patients knees with a focal cartilage lesion of the knee: using MRI T2 mapping and delayed gadolinium enhanced MRI of cartilage (dGEMRIC). Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Røtterud, Jan H; Engebretsen, Lars & Heir, Stig (2014). Microfracture technique versus osteochondral autologous transplantation mosaicplasty in patients with articular chondral lesions of the knee. A prospective randomized trial with long-term follow-up. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Røtterud, Jan H; Løken, Sverre Bertrand; Engebretsen, Lars & Heir, Stig (2014). Microfracture technique versus osteochondral autologous transplantation mosaicplasty in patients with articular chondral lesions of the knee. A prospective randomized trial with long-term follow-up. Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 22, p. S69–S70. doi: 10.1007/s00167-014-2843-6. Full text in Research Archive
• Røtterud, Jan H (2014). Impact of cartilage lesions on patient-reported outcome after ACL reconstruction. Full text in Research Archive
• Årøen, Asbjørn; Brøgger, Helga Marie; Røtterud, Jan H; Sivertsen, Einar; Engebretsen, Lars & Risberg, May Arna (2014). Evaluation of surrounding articular cartilage in 28 patients knees with a focal cartilage lesion of the knee: using MRI T2 mapping and delayed gadolinium enhanced MRI of cartilage (dGEMRIC). Knee Surgery, Sports Traumatology, Arthroscopy. ISSN 0942-2056. 22, p. S78–S79. Full text in Research Archive
• Ulstein, Svend; Bredland, K; Årøen, Asbjørn; Engebretsen, Lars & Røtterud, Jan H (2014). Ingen negativ effekt av fulltykkelse bruskskade hos fremre korsbånd rekonstruerte pasienter ved 5-9 års oppfølging. Full text in Research Archive
• Randsborg, Per-Henrik; Fuglesang, Hendrik Frølich; Røtterud, Jan H; Sivertsen, Einar & Hammer, Ola-Lars (2013). Selvrapporterte resultater 4,7 år etter kravebeinsbrudd hos pasienter i alderen 10-18 år. Full text in Research Archive
• Ulstein, Svend; Årøen, Asbjørn; Røtterud, Jan H; Løken, Sverre Bertrand; Engebretsen, Lars & Heir, Stig (2013). Microfracture technique vs mosaic plasty - No difference in knee scores at 5-11 years follow up in a prospective randomized clinical trial. Full text in Research Archive
• Røtterud, Jan H (2013). ACL-rekonstruksjon: Epidemiologi av ACL skader. Full text in Research Archive
• Røtterud, Jan H (2013). Articular carti-lage defects in ACL injuried knee. Full text in Research Archive
• Ulstein, S; Årøen, Asbjørn; Røtterud, Jan H; Løken, Sverre Bertrand; Engebretsen, Lars & Heir, Stig (2012). Mikrofraktur teknikk vs mosaikkplastikk for fokale bruskskader i kne, en prospektiv randomisert multisenterstudie med 5-10 års oppfølging. Full text in Research Archive
• Røtterud, Jan H (2012). Effekt av menisk- og bruskskade på pasientrapportert resultat etter rekonstruksjon av fremre korsbånd. Full text in Research Archive
• Røtterud, Jan H (2012). Articular cartilage lesion in the ACL-injured knee. Full text in Research Archive
• Røtterud, Jan H (2012). Incidence and risk factors for cartilage lesions in ACL-injuried knees. Full text in Research Archive
• Risberg, May Arna; Røtterud, Jan H; Engebretsen, Lars; Bolstad, Karin & Årøen, Asbjørn (2010). A PREOPERATIVE ACTIVE REHABILITATION PROGRAM FOR PATIENTS WITH A FOCAL KNEE CARTILAGE LESION SIGNIFICANTLY IMPROVED KNEE FUNCTION AND POSTPONED THE NEED FOR CARTILAGE REPAIR SURGERY. Osteoarthritis and Cartilage. ISSN 1063-4584. 18, p. S27–S28. Full text in Research Archive
• Ekeland, Arne; Engebretsen, Lars; Heir, Stig; Løken, Sverre; Nerhus, Kjetil & Røtterud, Jan Harald [Show all 7 contributors for this article] (2009). Fokale bruskskader og plager. En sammenligning. Full text in Research Archive
• Heir, Stig; Nerhus, Kjetil; Røtterud, Jan Harald; Løken, Sverre; Ekeland, Arne & Engebretsen, Lars [Show all 7 contributors for this article] (2009). Fokale bruskskader i kneet reduserer pasientenes livskvalitet like mye som langtkommen gonartrose. En sammenligning av KOOS i fire grupper knepasienter med fastslått indikasjon for kirurgi. Full text in Research Archive
• Heir, Stig; Nerhus, Kjetil; Røtterud, Jan H; Løken, Sverre; Ekeland, Arne & Engebretsen, Lars [Show all 7 contributors for this article] (2009). Fokale bruskskader i kneet reduserer pasientens livskvalitet like mye som langtkommen gonartrose. En sammenligning av KOOS i fire grupper knepasienter med fastslått indikasjon for kirugi. Norsk idrettsmedisin. ISSN 0806-9328. p. 23–23. Full text in Research Archive
• Røtterud, Jan H & Årøen, Asbjørn (2015). Focal cartilage lesions in anterior cruciate ligament-injured knees. Akademika forlag. ISSN 9788282649469. Full text in Research Archive
• Ekeland, Arne; Engebretsen, Lars; Heir, Stig; Løken, Sverre; Nerhus, Kjetil & Røtterud, Jan Harald [Show all 7 contributors for this article] (2009). Fokale bruskskader og plager. En sammenligning. Norges idrettshøgskole. Full text in Research Archive

View all works in NVA