Treatment of Hand Allodynia Resulting from Wrist Cutting with Radial and Ulnar Artery Perforator Adipofascial Flaps

Electrospun polycaprolactone (PCL)-amnion nanofibrous membrane prevents adhesions and promotes nerve repair in a rat model of sciatic nerve compression

Adhesion and scarring after neural surgery are detrimental to nerve regeneration and functional recovery. Amniotic membranes have been used in tissue repair due to their immunogenicity and richness in cytokines. In this study, an electrospun polycaprolactone (PCL)-amnion nanofibrous membrane was prepared for the treatment of sciatic nerve compression in a rat model. The effects of the PCL-amnion nanofibrous membrane on the prevention of adhesion formation and nerve regeneration were evaluated using electrophysiology and histological analyses. Compared with the medical chitosan hydrogel dressing, the PCL-amnion nanofibrous membrane significantly reduced peripheral nerve adhesion and promoted the rapid recovery of nerve conduction. Moreover, the immunohistochemical analysis identified more Schwann cells and less pro-inflammatory M1 macrophages in the PCL-amnion group. Western blot and RT-PCR results showed that the expression levels of type-Ⅰ and Ⅲ collagen in the PCL-treated rats were half of those in the control group after 12 weeks, while the expression level of nerve growth factor was approximately 3.5 times that found in the rats treated with medical chitosan hydrogel. In summary, electrospun PCL-amnion nanofibrous membranes can effectively reduce adhesion after neural surgery and promote nerve repair and regeneration. The long-term retention in vivo and sustained release of cytokines make PCL-amnion a promising biomaterial for clinical application.

A case series of seven patients with recurrent median nerve neuropathy treated by the revision surgery of median nerve neurolysis and wrapping with radial artery perforator adipose flap

Adhesion neuropathy of the median nerve with persistent pain can be a challenging problem. Currently, coverage of the median nerve with a well-vascularized soft tissue is deemed necessary after secondary neurolysis. Herein, we reviewed the outcomes of seven patients with a persistent median nerve neuropathy after a primary open carpal tunnel release or a median nerve repair, treated with neurolysis and median nerve wrapping with radial artery perforator adipose flaps. During the revision surgery, after a careful and complete neurolysis of the scarred median nerve, the distally based radial artery perforator adipose flap without its fascia was raised and rotated to wrap the median nerve. The mean size of the perforator flap was 1146 mm², which was enough to wrap the median nerve in all patients. At 26 months postsurgery, both the visual analog scale score for pain with tingling, and the patient-reported outcome measures improved. There was no recurrence of the median nerve adhesion neuropathy and no major complications were noted. Tinel's sign at the palmar wrist completely disappeared in four patients and was relieved in three patients. The median distal motor latency becomes recordable, and closer to a normal compound motor action potential postoperatively in all patients. Secondary neurolysis and median nerve wrapping with a radial artery perforator adipose flap, which was modified to be softer and thinner than the radial artery perforator adipofascial flap, was a successful treatment for the recurrent median nerve neuropathy in terms of both pain relief and restoration of the hand function.