GLIDING RESISTANCE OF EXTRASYNOVIAL AND INTRASYNOVIAL TENDONS THROUGHTHE A2 PULLEY

The gliding ability of the flexor digitorum profundus tendon and of th e palmaris longus tendon through the A2 pulley was compared, in terms of gliding resistance, with use of a system that we developed. Fourtee n digits and the ipsilateral palmaris longus tendons from fourteen cad avera were used. The average gliding resistance at the interface betwe en the palmaris longus tendon and the A2 pulley was found to be greate r than that between the flexor digitorum profundus tendon and the A2 p ulley under similar loading conditions. We concluded that the gliding ability of the palmaris longus tendon was inferior to that of the flex or digitorum profundus tendon in vitro. CLINICAL RELEVANCE: The findin gs of the present study are consistent with those of in vivo experimen ts in which extrasynovial tendon grafts have been associated with subs tantial formation of adhesions. The adhesions may be explained by the poor gliding ability of the palmaris longus tendon, The palmaris longu s tendon may have limitations, because of gliding resistance, when it is used as a graft to reconstruct flexor tendons in the digits.