THE INCIDENCE, ASSOCIATED FACTORS AND SURGICAL TREATMENT OF KNEE STIFFNESS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION.

Abstract

Aims: The aims of this study were to define the incidence of knee stiffness following ACL reconstruction, to determine which patient factors were associated with this, and to assess how effective arthroscopic arthrolysis has been in treating the stiffness.

Methods: To define the incidence of stiffness, we reviewed the patient records of a consecutive cohort of 100 primary isolated ACL reconstructions using quadruple hamstring autografts (2004–2006). Stiffness was defined as any loss of motion as compared to the contra-lateral leg. The mean age at reconstruction was 30 years and the median delay between injury and operation was 15 months. To assess the effectiveness of arthroscopic arthrolysis, we then reviewed all the patients who had undergone this procedure following primary isolated ACL reconstruction (n=18: 1997–2008). The mean age at arthrolysis was 31 years and the median delay between reconstruction and arthrolysis was nine months.

Results: Following primary ACL reconstruction, the incidence of stiffness was 12% six months postoperatively. Poor compliance with physiotherapy (p< 0.005), previous knee surgery (p< 0.005), and anterior knee pain (p< 0.029) were significantly associated with stiffness. A binary logistic regression found both poor compliance with physiotherapy (Exp(B)=6.931; 95%CI, 1.609–29.859; p< 0.009) and previous knee surgery (Exp(B)=6.383; 95%CI, 1.548–26.322; p< 0.010) to be significant predictors of the stiffness. The rate of stiffness fell to 5% at 12 months, without operative intervention. Of the 18 patients who underwent arthroscopic arthrolysis, the mean extension loss improved from 7° to 1° and the mean flexion loss improved from 8° to 2°. Arthroscopic arthrolysis was significantly more effective in restoring extension loss (p< 0.029) if carried out within eight months of the primary reconstruction.

Conclusions: Knee stiffness remains a significant problem post ACL reconstruction. This can however be effectively improved by appropriately timed arthroscopic arthrolysis.