Atelocollagen Injections Improve Outcomes in the Nonsurgical Treatment of Grade III Medial Collateral Ligament Injuries.

BACKGROUND: The purpose of this study was to evaluate the clinical outcomes of atelocollagen injections in isolated grade III medial collateral ligament (MCL) injuries of the knee joint.

METHODS: A total of 50 participants were included in this retrospective study. Twenty-six patients underwent conservative treatment with a single atelocollagen injection, while the remaining patients underwent only typical conservative treatment. All participants underwent magnetic resonance imaging to identify and grade MCL injury. Valgus stress radiography was performed on both knees at 6 and 12 months after the injury. The visual analog scale (VAS) score was collected at the first visit and at 2 weeks, 6 weeks, 6 months, and 12 months after injury. The International Knee Documentation Committee (IKDC) formula activity level and Lysholm score were evaluated for patient-reported outcomes at the first visit and at 6 and 12 months after injury. The participant's return to the pre-injury activity level ratio was measured by comparing the IKDC formula activity level at 12 months after the injury with that before the injury.

RESULTS: The VAS and Lysholm scores improved over time in both groups. The VAS and Lysholm scores were significantly better in the collagen injection group than in the control group. Regarding the activity level, the collagen injection group showed significantly better results at the 6-month follow-up, but there was no significant difference at the 12-month follow-up. The medial gap in the injured knee and the side-to-side difference (SSD) in both groups gradually decreased over time. The SSD in the collagen injection group was significantly smaller than that in the control group.

CONCLUSIONS: Atelocollagen injections resulted in better clinical and radiologic outcomes along with a higher rate of return to the pre-injury activity level, thereby exhibiting a positive effect in the nonsurgical treatment of grade III MCL injuries.