Natural history of fixed flexion deformity following total knee replacement

Abstract

We investigated fixed flexion deformity (FFD) after total knee replacement (TKR). Data relating to 369 cruciate-retaining unilateral TKRs performed at a single institution were collected prospectively. Fixed flexion was measured pre-operatively and at one week, six months, 18 months, three years and five years after surgery. Using binary logistic regression, pre-operative FFD was a predictor of post-operative FFD > 10 degrees at one week (p = 0.006) and six months (p = 0.003) following surgery. Gender was a predictor at one week (p = 0.0073) with 24% of women showing a FFD > 10 degrees compared with 37% of men. We have shown that a gradual improvement in knee extension can be expected up to three years after surgery in knees with FFD. By this time residual FFD is mild or absent in the majority of patients, including those who had a severe pre-operative FFD.

Sagittal placement of the femoral component in total knee arthroplasty predicts knee flexion contracture at one-year follow-up

“…However, these results should be compared with other designs of prosthesis. In addition, the 12-month investigation may not have been adequate to observe resolution of flexion contracture in a majority of patients [22]. Finally, the difference between the groups for distal femoral cut angle, even if statistically significant, has to be modulated by the accuracy of the navigation system, which is less than 1° [20].…”

“…Many studies have reported on knees with large flexion contracture [12,22,23] compared to a "normal" population. The original Knee Society score, prior to the Insall modification of 1993, considered flexion contracture of 0-4°as normal [24].…”

The natural history of a newly developed flexion contracture following primary total knee arthroplasty

“…Aderinto et al observed that the presence of a preoperative fixed flexion deformity was a good predictor for the development of post-operative fixed flexion deformity [21]. Moreover, they showed that postoperative flexion contractures improve with conservative management during the first three years.…”

“…While some studies have reported that the condition does not improve postoperatively [17][18][19][20], other investigators have shown gradual recovery with conservative management [19,[21][22][23][24]. It has been well established that the presence of a preoperative flexion contracture increases the risk of developing a postoperative flexion contracture [5].…”

“…It has been well established that the presence of a preoperative flexion contracture increases the risk of developing a postoperative flexion contracture [5]. However, the incidence and natural history of a newly developed flexion contracture in patients after total knee arthroplasty has not been extensively studied [4,21].…”