Separation of sutured tendon ends when different suture techniques and different suture materials are used. An experimental study in rabbits.

Calcaneal tendons in rabbits were divided and then sutured with varying suture techniques and suture materials. The separation of the tendon ends after suturing was registered with an X-ray technique--the tendon ends being identified by thin steel wires. Independently of the suture techniques and the suture materials a biphasic separation of the tendon ends was registered. The first separation took place during the first 4-5 days while the second separation began after 20-24 days. A small initial separation seems to indicate that the tendon suture used is adequate. The initial separation can therefore be used to evaluate a suturing technique and how the result is influenced by the suture material used. In the present study we could show that steel wire was ideal for a Bunnell suture. Prolene and Ethiflex cannot be recommended. A suture technique with a single short loop gave good results with all suture materials. Dexon ligatures placed around the tendon ends according to Schink in order to prevent the strands of the suture from cutting the tissue, did not reduce the initial separation. When a complex suture technique, like a Bunnell suture, is used the physical properties of the suture material influence the result. With a simple suture technique, a single short loop, good results can be achieved with every suture material.