Recovery of knee range of motion after total knee arthroplasty in the first postoperative weeks: poor recovery can be detected early

• DOI: 10.1007/s12306-019-00588-0
• Publication Date: 2019-01-09T03:34:59Z
• Authors: A. Kornuijt; G. J. L. de Kort; D. Das; A. F. Lenssen; W. van der Weegen
• Keywords: Aged, 80 and over; Male; Time Factors; Recovery of Function; Middle Aged; Sensitivity and Specificity; 03 medical and health sciences; Postoperative Complications; 0302 clinical medicine; Humans; Female; Postoperative Period; Prospective Studies; Range of Motion, Articular; Arthroplasty, Replacement, Knee; Aged

The aim of this study was to analyze in detail how knee flexion and extension progress in the first 8 weeks after primary total knee arthroplasty (TKA). The secondary goal was to compare knee range of motion (ROM) recovery patterns between patients with normal and delayed ROM recovery 8 weeks after TKA.This prospective clinical trial included all patients who underwent a primary unilateral TKA between February and December 2016 with weekly ROM data documented by the treating outpatient physical therapists (n = 137). Goniometry was used to measure knee ROM preoperatively, postoperatively on day 1 and weekly until follow-up at the orthopedic clinic 8 weeks after surgery. ROM recovery patterns were compared between patients with sufficient (≥ 90°) or insufficient (< 90°) knee flexion 8 weeks after TKA.Knee flexion recovered from a median of 80° in the first postoperative week to 110° 8 weeks after surgery and knee extension from a mean of - 10.7° to - 3.2°. Recovery was nonlinear, with greatest improvements in the first 4 weeks for knee flexion. In contrast to patients with sufficient knee flexion 8 weeks postoperatively, the insufficient group (n = 8, 5.8%) had poor knee flexion on the first postoperative day and from week 4 to week 8 almost no improvement or even worsening of knee flexion.Both knee flexion and extension recover in a nonlinear manner after TKA surgery. Poor postoperative knee function can be detected early, using ROM data from the first postoperative day up to the fourth week.