K. Kobayashi et al., The long-term effects of hyaluronan during development of osteoarthritis following partial meniscectomy in a rabbit model, OSTEO CART, 8(5), 2000, pp. 359-365
Objective: The long-term effect of hyaluronan (HA) on meniscus remodeling a
nd articular cartilage preservation was assessed during the development of
osteoarthritis following partial meniscectomy in a rabbit model.
Design: Approximately 60% of the region of each medial meniscus of 20 rabbi
t knees was excised bilaterally. The left knee joint was treated with five
weekly intraarticular injections of 0.3 mi of HA. beginning 1 week after su
rgery. The right control knee was injected with PBS on the same schedule. S
ix months after surgery, animals were killed and the medial menisci and tib
ial articular cartilage were evaluated morphologically, histologically and
biochemically.
Results: Meniscal regeneration was observed as newly synthesized translucen
t tissue, and image analysis revealed that the amount of this tissue was si
gnificantly greater in the HA-treated menisci than in the vehicle-treated m
enisci. Safranin-O staining and image analysis revealed the increased prese
nce of glycosaminoglycans in the HA-treated menisci relative to vehicle-tre
ated menisci while vascularity and biochemical parameters (hydration, total
GAGs and reducible collagen crosslinks) were statistically similar in HA-
and vehicle-treated menisci. Gross morphologic grading with India ink revea
led a trend for less deterioration of tibial articular cartilage in the HA
group (P=0.09) while Mankin's score of the HA-treated tibial articular cart
ilage was marginally lower than that of the vehicle group (P=0.06). Biochem
ical assessments showed a trend for higher total GAGs concentration in the
HA-treated articular cartilage when compared to the vehicle treatment group
(P=0.06).
Conclusion: The present study has demonstrated that following partial menis
cectomy, treatment with hyaluronan can enhance meniscal regeneration and ma
y inhibit articular cartilage degeneration as long as six months post surge
ry. (C) 2000 OsteoArthritis Research Society international.