Chronic Irreducible Knee Dislocations: Outcomes following Open Reduction and Reconstructive Surgery

Abstract

The management of unreduced knee dislocations who present late is challenging. The aim of this study was to determine the clinical, radiological, and functional outcomes following open reduction and reconstructive surgery for chronic irreducible knee dislocations. This retrospective study analyzed prospectively collected data of patients with an unreduced fixed anterior or posterior knee dislocation of 1 to 6 months' duration, treated with open reduction, hinged external fixator application, and ligament reconstruction who had a minimum 2-year follow-up. Patients were classified based on presence of prior periarticular surgery and direction of dislocation. Data on pre- and posttreatment clinical, radiological, and functional scores were analyzed. A total of 21 patients (age range: 19–43 years) fulfilled all inclusion criteria. These included 13 missed dislocations and 8 neglected postoperative dislocations. There were 18 posterior and 3 anterior dislocations. The mean follow-up was 6.9 years (range: 2.7–16.2 years). On final follow-up, all 21 patients were independently ambulatory with mean knee range of motion 127 degrees. No patient had symptomatic knee instability at final follow-up, despite four having isolated grade-III posterior cruciate ligament (PCL) laxity. Anatomical reduction was achieved in 19 patients, whereas 2 patients had incomplete joint reduction with a persistent grade-II fixed posterior subluxation. Scanograms revealed coronal alignment within 5 degrees of the opposite unaffected limb in 17 patients. Mean functional scores improved from preoperative 9.4 ± 4.7 (range: 2–19) to postoperative 75.9 ± 8.0 (range: 64–95) for Lysholm's and preoperative 10.7 ± 1.8 (range: 8.3–13.7) to postoperative 73.5 ± 6.7 (range: 66.7–88.7) for knee injury and osteoarthritis outcome score (KOOS) scores. Prior periarticular surgery was associated with significantly inferior Lysholm's scores (p < 0.04). Although 23.8% knees developed posttraumatic knee arthritis, no patient had undergone conversion to knee arthroplasty or arthrodesis. The study concludes that open reduction and reconstructive surgery is an effective surgical treatment for chronic irreducible knee dislocations of up to 6 months duration. An individualized, often staged approach that prioritizes joint reduction, early knee mobilization, and knee stability, ensures satisfactory clinical, radiological, and functional outcomes in the medium term. This is a clinical case series and reflects level of evidence IV.