Few long-term studies have been published assessing patient sporting activity following knee arthroplasty. The aim of this study was to investigate participation in sporting activities following knee arthroplasty with minimum 10-year follow-up. We hypothesised that patients undergoing unicompartmental knee arthroplasty (UKA) would participate in more sporting activity than patients undergoing total knee arthroplasty (TKA).

Between January 2004 and September 2006, 141 TKAs and 41 UKAs were performed. Patients over 75, those who underwent additional surgery to the ipsilateral limb and patients with bilateral procedures were excluded. Eight patients in the TKA group and two patients in the UKA group are since deceased for reasons unrelated to their knee arthroplasty. Four patients have had revision surgery to convert a UKA to a TKA and were excluded. Therefore, 76 patients in the TKA group and 31 patients in the UKA group were contacted at the time of this study by postal questionnaire or telephone. The mean age was 73.7 +/- 8.1 years (range, 47-85) in the TKA group and 75.0 +/- 7.7 (range, 61-88) in the UKA group at the time of this study. The questionnaire assessed their participation in low impact sports detailing number and length of sessions, how the knee felt during sport and their overall satisfaction.

Twelve patients in the TKA group and five patients in the UKA group were lost to follow-up therefore the final analysis consisted of 64 patients (84.2%) in the TKA group and 26 patients (83.9%) in the UKA group. 46 patients in the TKA group (71.9%) versus 21 patients in the UKA group (80.8%) participated in low impact sport at 10-year follow-up. (p=0.193) Patients in the UKA group participated in 2.4 sessions per week compared to 1.5 sessions per week in the TKA group. (p=0.016) The average minimum session length was 39 minutes in the TKA group and 60 minutes in the UKA group. (p=0.069) 32 patients (69.9%) in the TKA group versus 16 patients (76.2%) in the UKA group denied pain whilst playing sport and 39 patients (84.8%) in the TKA group versus 19 patients (90.5%) in the UKA group felt their joint was stable during sport. The most commonly named reason for reduction in sporting activity in the TKA group was pain in the replaced joint (45%) whereas in the UKA group it was pain in other areas (50%). 84.3% of patients in the TKA group and 92.3% of patients in the UKA group were satisfied or very satisfied 10 years postoperatively.

This study demonstrates satisfactory participation in sporting activity and good survivorship 10 years following knee arthroplasty. Our short-term study found significantly greater numbers of UKA patients returned to sport and participated in more sporting sessions with longer session lengths than TKA patients. This study confirms these findings demonstrating UKA patients participate in significantly more sporting sessions and tended towards longer sessions than TKA patients. Additionally, more UKA patients were satisfied with the outcome of surgery at the time of this study and fewer patients reported pain during sport.