Clinical, functional, and patient-reported outcome of traumatic knee dislocations: a retrospective cohort study of 75 patients with 6.5-year follow-up

Introduction: At present, limited knowledge regarding clinical, functional, and patient-reported outcomes at mid- and long-terms after surgical treatment of traumatic knee dislocations is available. This study aimed to investigate the mid-term recovery regarding clinical, functional, and patient-reported outcomes in patients following knee dislocation with associated multi-ligament injuries.

Materials and methods: The study design was a cross-sectional cohort study. Data were collected by retrospective chart review, clinical examination, and interview of patients. All patients treated surgically following a knee dislocation between January 2000 and December 2011 were included. The surgical technique was up to the decision of the individual surgeon. The main outcome was the Lysholm knee score. Secondary outcomes consist of clinical knee examination, functional performance test, pain, and patient-reported outcome across several domains in function, sport, pain, and quality of life.

Results: Seventy-five patients (66.3%) accepted the invitation to participate. The mean age at the time of knee dislocation was 33.5 years, with a range of 16-65 years of age. The mean follow-up time was 78 months (R: 17-147). 75% of patient a Schenck's type 1 lesion and 23% a type 3. The median Lysholm knee score was 83 (R: 18-100). The mean KOOS for the five subscales were pain 84.5 (95% CI 80.5-88.5), symptoms 75.1 (95% CI 70.7-79.4), ADL 87.0 (95% CI 83.1-90.9), sport 59.9 (95% CI 53.3-66.4), and QOL 71.3 (95% CI 67.0-75.6). The mean Tegner activity level was 5.1 (95% CI 4.5-5.7). The median single assessment numeric evaluation (SANE) was 93 (R: 0-100). The pain intensity score for pain (VAS) during activity was reported with a mean of 2.7 (95% CI 2.1-3.3). The objective IKDC examination showed 76% of patients grouped by Grade A (normal knee function) or Grade B (nearly normal).

Conclusion: With a mean follow-up of 6.5 years, combined repair and reconstruction surgery following a knee dislocation shows good to excellent patient-reported outcome and more than 75% of patients experiencing normal knee functioned evaluated by the IKDC score.