Sir,—It is with great interest that I read the recently published paper by Porsius and co-workers (Porsius et al. 2018). However, I am worried that the authors may not have obtained a valid estimate of hip function and pain using the Oxford Hip Score (OHS) (Dawson et al. 1996), which the authors define as their main outcome measure. Using the OHS, the authors have assessed hip function and pain 1 week before surgery and every week for the first 6 weeks after surgery in patients recovering from a total hip replacement. However, the OHS uses a recall period of 4 weeks (Dawson et al. 1996). I cannot find information in the paper regarding a potential modification of the originally validated version of the OHS. Could the authors please help explain?
Thomas Bandholm
Clinical Research Center, Amager-Hvidovre Hospital,
University of Copenhagen, Denmark
Department of Orthopedic Surgery, Amager-Hvidovre
Hospital, University of Copenhagen
Department of Physical and Occupational Therapy, Amager-
Hvidovre Hospital, University of Copenhagen, Denmark
Email: [email protected]
Sir,—We thank T Bandholm for his interest in our study especially concerning the weekly use of the Oxford Hip Score (OHS) as main outcome measure. In our study we used data that was obtained using a diary as reported in another study (Klapwijk et al. 2017). The OHS was assessed pre-operatively, and post-operatively on a weekly basis. To align with the goals of a diary study, we omitted the usual 4-week time frame used in the postoperative OHS questionnaire. In line with the other questions that were assessed daily in the diary, patients filled out the OHS for their current situation.
We are not aware of studies reporting on the effects of the specific recall period on the OHS. In our opinion, a change of the recall period, which we believe was necessary for our research goal, does not lead to an invalid estimate of hip function and pain. However, it would be prudent not to compare our absolute post-operative scores directly to other studies using a 4-week time frame OHS. Our results should only be interpreted in line with the goal of our study, which was to characterize subgroups of patients according to their hip function trajectory in the first 6 weeks after primary THA.
On behalf of all authors
Jarry Porsius
Department of Plastic and Reconstructive Surgery &
Department of Rehabilitation Medicine, Erasmus University Medical Center Rotterdam, the Netherlands
Email: [email protected]
- Dawson J, Fitzpatrick R, Carr A, Murray D. Questionnaire on the perceptions of patients about total hip replacement J Bone Joint Surg Br 1996; 78(2): 185–90.
- Klapwijk LC M, Mathijssen N M C, van Egmond J C, Verbeek B M, Vehmeijer S B W. The first 6 weeks of recovery after primary total hip arthroplasty with fast track. Acta Orthop. 2018;89(1):140.
- Porsius J T, Mathijssen N M C, Klapwijk-Van Heijningen L C M, Van Egmond J C, Melles M, Vehmeijer S B W. Acta Orthop 2018; 89(6): 597–602.