Abstract
Objectives: This study aims to assess the psychological profile of patients prior to total knee replacement, medial unicompartmental knee replacement and patellofemoral joint replacement and determine its effect on outcome.
Methods: 113 patients were identified (41 TKR, 37 UKR and 35 PFJR). All patients had mental health assessed preoperatively using SF-12. From the 12 questions a mental and a physical summary score can be calculated (MCS and PCS). The reduced WOMAC score was used pre-operatively to assess knee function and symptoms and then recorded at 8 and 24 months post-operation to assess outcome.
Results: 54% of the patients had pre-operative psychological distress. There was no statistically significant difference demonstrated between them mean MCS scores between the three operation groups. Pre-operative MCS had a significant effect such that increasing psychological distress lead to a worse twenty-four month outcome (p = 0.016). The effect of MCS is most marked in postoperative pain levels (p = 0.008) compared to function (p = 0.016). The mean 24-month rWOMAC in the severely distressed group (MCS< 40) was 28.4 compared to 17.4 in the psychologically well group (MCS> 60).
Conclusions: Pre-operative mental function prior to knee arthroplasty may provide useful information to guide patients as to their expected outcome in the consent process. Those patients with a very high mental component may be counseled to that although their distress is likely to improve with surgery, their eventual outcome may be worse. The effect of MCS may however only be clinically relevant in those patients with severe mental symptoms.
Correspondence should be addressed to Mr T Wilton, c/o BOA, BASK at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England.