Delaying knee replacement and implications on early postoperative outcomes: a pilot study

The goal of this study was to compare outcomes during postoperative rehabilitation between individuals who delayed surgery to those who did not delay surgery. Forty-two patients who underwent unilateral total knee replacement (TKR) were categorized into 2 groups: early surgical (n=30, surgery 324 days prior) and late surgical (n=12, surgery >or=325 days from the initial orthopedic office visit). The KSKS, KSFS, SF-12 PC summary, and AROM for knee extension and flexion were assessed preoperatively. The WOMAC, weight bearing during a 30 degrees (SQ30) and 60 degrees (SQ60) squat, and the Timed Up and Go were assessed at the initial visit and discharge of rehabilitation. A Mann-Whitney was used to assess for differences between groups for the WOMAC pain and physical function dimensions at the initial visit and at discharge. A 2x2 ANOVA was used to assess for differences between groups at the initial visit and at discharge for SQ30, SQ60, and Timed Up and Go. Independent t tests were used to assess for differences between groups for clinical measures taken preoperatively. Effect sizes were calculated over postoperative rehabilitation. Regardless of time, the late surgical group placed significantly less body weight on the involved side during SQ30 and took longer to complete the Timed UP and Go. The late surgical group reported greater pain at the initial visit and greater difficulty with functional activities at the initial visit and discharge. Change scores were similar in both groups and effect sizes were moderate to high. Individuals who delayed surgery, for whatever reason, did not perform at levels of their counterparts who had shorter waiting times.