Objective

The objective of this study was to determine whether activity tartrate-resistant acid phosphatase (TRAP) in synovial fluid (SF) and serum is a useful marker for induced osteoarthritis (OA) secondary to experimental rupture cranial cruciate ligament in the dogs.

Methods

Ten skeletally mature beagle dogs underwent unilateral surgical transection of cranial cruciate ligament, medial collateral ligament and medial menisectomy. 23 normal dogs served as controls. SF was collected from the femoropatellar compartment of the affected stifle joint by direct arthrocentesis every a month during 4 month. The TRAP activity in stifle joint SF and serum was determined using spectrophotometer with p-nitrophenylphosphatase (pNPP) substrate. An addition, the presence of TRAP positive cell in synovium and CCL were identified by enzyme histochemistry.

Results

The activity of TRAP in SF of induced OA was increased when compared with SF of normal dogs during 3 month (p<0.05), but there is not significant in serum. Macroscopically visible surface fibrillation, cleft and focal erosions appeared 1 month after postoperative in the femorotibial joint; predominantly on the medial tibial plateau and medial femur. On histochemistry, increased cellular of TRAP positive cell was detected in synovium and cranial cruciate ligament.

Conclusion

In this induced OA, activity of TRAP in SF appears to provide a useful marker of the degenerative changes.