A randomized biomechanical study of zone II human flexor tendon repairs analyzed in an in vitro model.

To study the effect of dorsally placed flexor tendon repairs on human cadaver tendons, we used the Kessler, Strickland, Robertson, and modified Becker techniques. The strengths of the repairs were tested in a previously described human cadaveric curvilinear model. There were statistically significant increases in dorsal versus volar grasping strength with the Kessler repair (38 N vs 33 N) and the Robertson repair (51 N vs 43 N). There were no differences with the locking Strickland and modified Becker repairs. One may infer that the locking techniques are intrinsically tighter and may not be as susceptible to the different forces between the tensile and compressive surfaces of a dynamic flexor tendon.