Digital public defence: Ole-Christian Laahne Brun Ole-Christian Laahne Brun at Institute of Clinical Medicine will be defending the thesis Post-operative findings and patient-reported outcomes in total hip arthroplasty following the introduction of the minimally invasive direct anterior approach for the degree of PhD (Philosophiae Doctor). 

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The public defence will be held as a video conference over Zoom.

The defence will follow regular procedure as far as possible, hence it will be open to the public and the audience can ask ex auditorio questions when invited to do so.

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Due to copyright reasons, an electronic copy of the thesis must be ordered from the faculty. In order for the faculty to have time to process the order, it must be received by the faculty no later than 2 days prior to the public defence. Orders received later than 2 days before the defence will not be processed. Inquiries regarding the thesis after the public defence must be addressed to the candidate.


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Adjudication committee

  • First opponent: Professor Anders Troelsen, University of Copenhagen, Denmark
  • Second opponent: Associate Professor Tina Strømdal Wik, Norwegian University of Science and Technology, Trondheim
  • Third member and chair of the evaluation committee: Professor II Angelika Sorteberg, Institute of Clinical Medicine, University of Oslo

Chair of defence

Professor II Iver Arne Langmoen, Institute of Clinical Medicine, University of Oslo

Principal supervisor

Professor II Lars Nordsletten, Institute of Clinical Medicine, University of Oslo


To date, the various surgical approaches used in total hip arthroplasty (THA) vary greatly, 
and there is insufficient data to determine the optimal choice of approach in patients with 
end-stage osteoarthritis needing elective THA. We therefore conducted trials to explore
the department-level learning curve, as well as patient-related outcome measures (PROMs)
and post-operative findings following the introduction of the minimally invasive direct 
anterior (MIDA) approach.

A prospective database study, a retrospective database study, and a level 1 prospective randomised controlled study (RCT) were conducted in mostly elderly patients at two level 2 hospitals in South Eastern Norway. Post-operative PROMs, complications, and radiographically assessed acetabular and femoral component placement were registered and assessed both during and following the introduction of the MIDA approach.

The findings suggest that outcomes improve gradually within a range of good results, especially following the first couple of 100 patients operated. The main difficulty in learning and establishing the MIDA approach; a new and relatively complex orthopaedic surgical technique, might seem to be primarily related to femoral access and femoral component positioning, as indicated by the relatively high frequency of stem subsidence at our department. Fractures of the greater trochanter may impact the outcomes following THA; however, such fractures do not occur more frequently using the MIDA approach compared to the DLA in our study population. 

In a patient population treated after the learning of the MIDA approach had been established, radiographically assessed component placement showed similar results in the two approaches, suggesting the MIDA approach is both safe and effective in THA.

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Published Jan. 13, 2021 10:23 AM - Last modified Jan. 28, 2021 9:15 AM