[Perineural fibrosis of the median nerve at the wrist. Treatment by neurolysis and dermal-hypodermal graft].

UNLABELLED: In the treatment of multiple recurrences of carpal tunnel syndrome due to fibrosis, following repeated nerve release, the authors propose interposition of a composite dermal fat graft raised from the inguinal region, and report four clinical cases using this technique. The objective of this study was to evaluate the efficacy of the graft in terms of clinical and electromyographic results and determine the course of the graft by a postoperative MRI study and a longer follow-up. CLINICAL RESULTS: Nocturnal paraesthesiae resolved in 2 patients, was improved in one patient and remained unchanged in another patient. Objectively, neurological examination showed improvement in 3 cases and no change in 1 case. Electromyographic results: At last follow-up, EMG was improved in only one case. Magnetic resonance imaging: MRI visualized the graft with a fat signal on T1-weighted sequences in every case, with an increase in size over time in 3 cases. The efficacy of the dermal fat graft may seem disappointing, as none of the patients were cured. However, with a mean follow-up of more than two years, we have not observed any deterioration of the clinical features, and no surgical revision for carpal tunnel syndrome. This technique appears to increase graft survival, as the blood supply to the subdermis is restored more rapidly via the dermis, which is anatomically a very vascular tissue. There is nevertheless a discrepancy between the clinical results, and EMG and MRI findings, which could be explained by the anatomical lesion of the median nerve, surgically released several times, and by alterations of the perineurium.