Abstract
Aim
The purpose of this study was to develop and test the utility of a hybrid barbed-suture in the core repair of digital flexor tendon injuries. Despite offering advantages over traditional suture methods, concerns over the cost, strength to failure and biocompatibility of barbed sutures have hindered their development. Moreover the recent designs have been very complex. We have attempted to develop and test a simple barbed suture, to assess it's viability in flexor tendon repair and in particular to establish a baseline for the efficacy and modes of failure barbed sutures, in order to help provide a basis for future research.
Method
The barbed suture device was constructed by inserting 3 steel barbs into the weaved construct of a braided polyester suture. The barbed sutures were inserted into 28 porcine lateral extensor tendons yielding a single sided core repair. Tensile testing of the repair was undertaken using a tabletop load frame with the distal end of the tendon fixed in a cryo clamp.
Linear load testing to failure was undertaken. Maximum load, repair excursion and repair stiffness were recorded.
Results
The barbed suture technique demonstrated a maximum load to failure of 40.4±16.4N. The excursion of the repair at failure point was 31.4±11.6mm. The stiffness of the repair derived from the linear elastic portion of the load displacement curve was 1.0±0.6N/mm.
Conclusions
Use of this barbed suture construct offers a fast, easily applied method of flexor tendon repair. The maximum load to failure is comparable to the commonly used non-barbed suture methods. The suture excursion and stiffness findings suggest gap formation at low loads. Failure of the barbed suture seemed to be resisted by the collagen links between longitudinal tendon fibres. Further developments of this very modifiable construct may lead to a viable alternative to the current repair techniques.
