Summary
The aim of this study was to determine the effects of intra-articular hyaluronic acid
on meniscal healing. Circular defects, 1.0 mm in diameter, were made in the anterior
third of the medial meniscus in rabbits. In one joint, 0.4 ml hyaluronic acid (Healon®) was instilled, and in the contralateral (control) joint, 0.4 ml Ringer’s saline.
Four rabbits were killed after four, eight and 12 weeks and the menisci examined histologically.
By eight weeks most of the lesions had healed by filling with hyaline-like cartilage.
Healing was not improved by hyaluronic acid treatment. The repair tissue stained strongly
with alcian blue, and the presence of type II collagen, keratan sulphate, and chondroitin
sulphate was demonstrated by immunohistochemical localisation. In contrast to the
circular defects, longitudinal incisions made in the medial menisci of a further six
rabbits did not show any healing after 12 weeks, indicating that the shape of the
lesion largely determined the potential for healing.
The effect of hyaluronic acid on meniscal healing was tested in a rabbit model. With
one millimeter circular lesions in the medial meniscus, healing by filling with hyalinelike
cartilage was not significantly affected by the application of hyaluronic acid intra-articularly
at the time of surgery, compared to saline controls, as assessed histologically four,
eight and 12 weeks after the operation.
Keywords
Meniscal repair - hyaluronic acid - type II collagen