Feasibility of Stifle Medial Meniscal Release in Toy Breed Dogs with and without a Joint Distractor.

Abstract

To investigate the feasibility of medial meniscal release (MMR) during stifle arthroscopy in toy breed dogs with and without a joint distractor. Experimental cadaveric study. Stifles (n = 40) from 20 canine cadavers (1.8-5.1 kg). Paired stifles were randomly assigned to the joint distractor group and the control group (n = 20 each). All stifles underwent arthroscopic transection of the cranial cruciate ligament followed by a release of the caudomedial meniscotibial ligament. After the procedures, all stifles were disarticulated. The degree of released meniscus was recorded subjectively by 5% increments. A MMR success was defined as a complete transection. The areas of femoral and tibial articular cartilage damage were calculated using india ink staining and digital imaging. The results were compared between groups and odds ratios were calculated. All stifle arthroscopies were successful. The success rate of MMR was significantly higher (P = .013) with a joint distractor than without a joint distractor. MMR was 7.4 times more likely to succeed with a joint distractor than without a joint distractor. The distal femoral articular cartilage was significantly more damaged (P = .011) in the stifles without a joint distractor than in the stifles with a distractor. No difference was found between the 2 groups for damage to the tibial cartilage (P = .058). Stifle arthroscopic MMR is feasible in toy breed dogs. Using a joint distractor is recommended for arthroscopic treatment based on our results because it significantly reduced the rate of incomplete release as well as iatrogenic cartilage damage.