ABSTRACT
Large meniscal defects are a common problem for which treatment options are limited.
Successful meniscal regeneration has been achieved by using grafts of small intestinal
submucosa in posterior, vascular meniscal defects in a dog model. This study investigates
the long-term effects of a tibial tunnel fixation technique and a clinically based
meniscectomy defect on meniscal regeneration using this model. Eight mongrel dogs
underwent medial arthrotomy and partial meniscectomy. The dogs were divided into groups
based on defect treatment: small intestinal submucosa (n=4) or meniscectomy (n=4).
Dogs were scored for lameness by subjective scoring postoperatively, sacrificed at
6 months, and assessed for articular cartilage damage, gross and histologic appearance
of the operated meniscus, amount of new tissue in the defect, and relative compressive
stiffness of articular cartilage.
Dogs in the meniscectomy group were significantly (P=.002) more lame than dogs treated with small intestinal submucosa. Small intestinal
submucosa-treated joints had significantly (P=.01) less articular cartilage damage than meniscectomy joints. Small intestinal submucosa
meniscal implants resulted in production of meniscal-like replacement tissue, which
was consistently superior to meniscectomy in amount, type, and integration of new
tissue, chondroprotection, and limb function during the study period. Small intestinal
submucosa implants may be useful for treatment of large posterior vascular meniscal
defects in humans. The tibial tunnel technique used for fixation may have clinical
advantages and therefore warrants further investigation.
