The effect of collagenase clostridium histolyticum on adhesion reduction in a rat knee arthrofibrosis model

OBJECTIVE The aim of this study was to investigate whether collagenase clostridium histolyticum (CCH) reduces intra-articular fibrotic adhesion formation in a rat model of arthrofibrosis. METHODS A total of 24 male Wistar rats (7 months old, weighing 220 -275 g) were randomly and equally assigned to one of two groups: the collagenase group and the control group (n = 12 each). In each group, a partial capsulotomy, and synovectomy were performed in knee. After a partial capsulotomy and synovectomy were performed in each group, the collagenase group received intra-articular CCH of 0.008 mg in 0.1 mL saline solution while the control group received the equal volume of intra-articular saline solution alone. After 6 weeks of surgery, the rats were sacrificed by decapitation, and the following outcome measures were collected. Knee range of motion (ROM) was measured using with a goniometer under 20 g force. Adhesion formation was rated using the macroscopic visual scoring system after the knee joint was exposed through a lateral parapatellar approach. Histological evaluation was performed on samples including connective tissue and fibrotic adhesions, and fibroblast cell numbers were measured performed per square. Levels of interleukin 1 (IL-1) and fibroblast growth factor (FGF) were assayed by ELISA from the intra-articular fluid. RESULTS The macroscopic visual scoring system was significantly lower in the collagenasegroup (median = 1, range = 0-2) than in the control group (median = 2, range = 1-3)( < 0.001).ROMwas significantly higher in the collagenase group (102° ± 12.1°) than in the control group (77° ±8.94°) (P