Sodium hyaluronate as an adjunct in adhesion prevention after flexor tendon surgery in rabbits.

Topical application of sodium-hyaluronate (NaHe) has been proposed to decrease the formation of adhesions after tendon surgery, but reports published thus far have been contradictory. A new test instrument capable of simultaneous registration of tensile load, tendon excursion, and joint motion was therefore developed and used to evaluate the effect of locally administered NaHe of different concentrations and molecular weights on the outcome after tenorrhaphy of rabbit hindlimb flexor tendons. Immediately after tenorrhaphy, NaHe or saline solution was deposited into the tendon sheath. The functional characteristics of the digits were evaluated 15 days after surgery. NaHe with a concentration of 19 mg/ml and a molecular weight of 6 x 10(6) significantly limited the strength of the adhesions formed without impairment of tensile strength. These results suggest that the efficacy of NaHe is affected by both the concentration and the molecular weight of the NaHe preparation used.