This study was undertaken to elucidate the natural healing potential in posterior cruciate ligament (PCL) injury using histological and biomechanical methods.

PCLs of 92 rabbits were cut partially or completely cut on one side. In Group I, 75% of the PCL was cut preserving the synovium partially. In Group II, the PCL and synovium were completely severed. Investigations were performed by gross inspection, histological examination after Hematoxylin-Eosin (HE) staining and tensile stress testing using an Instron.

Continuity of the ligaments began to appear at 2 weeks in group I and at 12weeks in group II. Proliferation of fibroblasts and vessels were observed in HE stained ligaments at 6 and 12 weeks in both groups. The ultimate tensile strength in group I was 45.3% and in group II 33.1% at 12 weeks.

Although the mechanical properties of the regenerated ligaments were poor, this study demonstrats that the rabbit PCL has healing potential irrespective of the degree of injury.