Combined posteromedial or posterolateral PCL injuries: Anatomic repair and ligament bracing as a new treatment option - first results of a multicentre study

AIMS AND OBJECTIVES: Acute, isolated PCL injuries can succesfully be managed non-operatively whereas combined PCL injuries usually require surgical management. Currently, there is a lack of evidence regarding the standard of treatment (repair vs. reconstruction, one-stage vs. two-stages procedures). Suture augmented repair leads to good and excellent results in cases of acute knee dislocations. This technique has not been investigated clinically in combined PCL injuries, yet. The aim of this multicentre study was to evaluate the clinical outcome after surgical repair with additional suture augmentation (ligament bracing) of all torn ligaments in acute combined pcl injuries (posteromedial or posterolateral). MATERIALS AND METHODS: From 2016 to 2018, 25 patients with an acute combined PCL injury were treated with one stage anatomical repair and ligament bracing of the torn ligaments within 14 days at 6 trauma centres (5xGER, 1x SUI). Inclusion criteria: Follow-up min. 6 months, age > 18y. Exclusion criteria: ACL Injury, posteromedial AND posterolateral injury. During the follow-up evaluation, various scores were collected (International Knee Documentation Committee IKDC Score, Tegner Score , KOOS and Lysholm Score). Additional stress radiography was performed (TelosTM) postoperatively. RESULTS: For now 14 combined PCL injuries (posteromedial or -lateral) with a follow-up of 20 months (range 8-33) were evaluated. 10 patients had a posteromedial (PCL + MCL/POL), 4 patients had a posterolateral (PCL + LCL) injury. 10 additional articular lesions were detected (6 meniscus tears, 4 grade IV chondral lesions) and 1 transitional peroneal nerve injury. The average IKDC score was 62.2±18.5, the average Lysholm score was 78±19.2, average KOOS 88.7±7.6. Median loss of activity in the Tegner score was 1 (range 0-5) point. Side-to-side pcl-stress-radiographs showed a difference at a mean of 4.8±3.0mm (range 1-10). 2 cases with symptomatic knee instability, both posterolateral, and 3 patients with knee stiffness needed reoperation. Interestingly, patients with posteromedial injuries showed predominantly good or excellent results according to Lysholm score and were graded as A (4/10) or B (2/10) whereas ligament bracing in posterolateral combined injuries had a high failure rate (Grade D 2/4). CONCLUSION: Primary anatomic repair and additional suture augmentation predominantly leads to good and excellent clinical results in cases of combined posteromedial PCL injuries. Patients with posterolateral injuries showed inferior clinical outcome and relatively high instability rates following ligament bracing. In conclusion, primary augmented suture repair seems to be a promising treatment option. The overall results of this study have to be evaluated for more exact recommendations.