The multiple ligament-injured knee: When is primary repair an option?

Treatment of multiple ligament-injured knees (MLIKs) remains complex and most often requires ligament reconstruction surgery. Reconstruction effectively restores knee stability but the procedure is invasive and can be complicated by stiffness or arthrofibrosis. There has been recent resurgence of interest in primary repair of knee ligaments. The goal was therefore to assess incidence of repairable ligaments in MLIKs, and determine patient and injury characteristics associated with potential for primary repair.

A retrospective review of all MLIK patients surgically treated between 2009 and 2018 was conducted. All patients were treated with the same algorithm: primary repair was performed if the ligament was proximally or distally avulsed, and otherwise, reconstruction was performed. Patient characteristics, injury patterns, treatment specifics, and short-term outcomes were compared using independent t-tests and chi-square tests.

Forty-eight patients were included (mean age 32 years ± 14; 54% were male). Ultimately, 55% of ACL, 73% of PCL, 88% of MCL/PMC, and 87% of LCL/PLC injuries were repaired. Patients above 35 years (OR 6.9, P = 0.010) and higher BMI (OR 3.5, P = 0.046) were more likely to undergo ACL repair. No significant correlation was found in other ligaments. At a minimum of six-month follow-up (range 0.5-7.2 years), ACL repair failed in nine percent, PCL repair in 17%, MCL/PMC repair in 0%, and LCL/PLC repair in 18% of patients.

This study noted high incidences of repairable ligaments when MLIKs are treated within six weeks following injury. Although preliminary outcomes following primary repair in MLIK are good, further long-term follow-up studies are needed.