Long-Term Outcome of Patients Treated Surgically for Traumatic Knee Dislocation: Does the Injury Pattern Matter?

Abstract

Aims: To examine the difference in outcomes of patients treated surgically for traumatic knee dislocation with regard to different injury patterns. Methods: All patients who underwent reconstruction/repair of the cruciates and primary complete repair of collaterals, posterolateral, and posteromedial corner structures were allocated to 3 groups (group A: bicruciate injury with associated medial side injury [n = 31]; group B: bicruciate injury with associated lateral injury [n = 20]; group C: bicruciate injury with associated medial and lateral injury [n = 23]). Outcome was assessed at a mean of 12 years postoperatively using the International Knee Documentation Committee (IKDC) score, Short Form-36 (SF-36) health survey, Lysholm score, Tegner score, visual analog scale (VAS) pain score, and Knee Society score. Anterior-posterior laxity was also measured (KT1000™ arthrometer; Medmetric Corp., San Diego, CA), and Pearson's correlation was used to compute associations between variables (P < 0.05). Results: The mean time to return to work was 6 ± 4 months in group A, 13 ± 19 months in group B, and 11 ± 12 months in group C. At final follow-up, 7 patients had a pain VAS of > 3 (group A: 6 patients; group B: 0 patients; group C: 1 patient). Seven patients could not flex their knee > 110° (group A: 4 patients; group B: 0 patients; group C: 3 patients). Eighteen patients (24%) presented with an extension deficit of > 5°. Valgus stress testing was > 3 mm in 12 patients (group A, 3 patients; group B, 4 patients; group C: 5 patients). Varus stress testing was > 3 mm in 9 patients (group A: 4 patients; group B: 3 patients; group C: 2 patients). The dial test at 30° showed < 6° (normal) and 6° to 10° (nearly normal) in 64 patients, and > 10° (abnormal) in 10 patients (group A: 4 patients; group B: 2 patients; group C: 4 patients). At 90° flexion, the difference was < 10° in 70 patients and > 10° in 4 patients (group A, 1 patient; group B: 1 patient; group C: 2 patients). Normal/nearly normal IKDC score values were found in 19 patients in group A, in 12 patients in group B, and in 14 patients in group C. There were no significant differences in outcome between the groups, except patients with an injury of the lateral collateral ligament and/or the peroneal nerve who had a greater need for workers compensation (P < 0.01). Conclusion: Early complete 1-stage reconstruction/repair showed good subjective and functional results with restoration of working capacity, independent from the location of associated injuries (medial, lateral, and medial and lateral). A peroneal nerve lesion resulted in significantly poorer outcome.