Comparison of Mechanical Properties of Polyurethane Nanofilament Pulley with Natural Pulley as a Synthetic Structure (A Cadaveric Study)

 Pulley is a synovial tissue that attaches the flexor tendons to the dorsal portions of the fibro-osseous tunnel near the tendon attachment. Pulley type A with ring structure is one of the most important pulleys in fingers. Two-stage reconstruction by silicon is the common treatment in damaged tendon which has long recovery time and the tendency of the repaired tendon to adhere to the fibrous-bone tunnel around it. Accordingly, the one-stage reconstruction by synthetic pulley is a promising approach to resolve the mentioned problems.
 

 In the present research, the polyurethane (PU) nanofiber scaffolds have been designed for synthetic pulley applications, and their mechanical and structural properties have been evaluated.

 The structural properties of nanofiber scaffolds show similar properties to protein and polysaccharide fibers in the extracellular matrix (ECM). The Fourier transform infrared spectroscopy (FTIR) results confirmed the functional groups of PU without any unwanted reactions. The amount of stress (3.19 ± 0.54) and Young's modulus (1.20 ± 0.39) in PU nanofiber scaffolds show similar mechanical properties to natural pulley.

 The obtained results showed that the PU nanofibers scaffolds can be proposed as a suitable candidate for fabrication of synthetic pulley in flexor tendon injuries.