Re-Neurolysis and Infiltration of Autologous Lipoaspirate Around the Median Nerve in Secondary Recurrent Carpal Tunnel Syndrome: A Prospective Cohort Study

Background: Release of the flexor retinaculum in carpal tunnel syndrome (CTS) is a frequently executed operation. Recurrent CTS is mostly caused by new fibrous perineural adhesions around the median nerve. Extensive neurolysis is advised in a first recurrent episode. In case of secondary recurrence, addition of an interposition of vascularised fat- fascia or muscle- tissue after an extensive neurolysis is suggested. Most of these techniques are labour-intensive and cause donor site morbidity. The authors hypothesised that lipografting following extensive neurolysis reduces postoperative recurrence of CTS. Methods: In this prospective cohort study, patients with a 2nd to 5th recurrent CTS (N=25) are included and treated with extensive external neurolysis followed by perineural lipografting. Primary outcome is the Boston Carpal Tunnel Questionnaire (BCTQ). Secondary outcome is electrodiagnostic nerve conduction velocity obtained with electromyography (EMG). Data are obtained pre-and post-operatively with a mean follow-up of 30 months. Findings: A significant decrease of 1.3 of the total BCTQ scores was seen postoperative (p<0.05) with an improvement in both SSS (Symptom Severity Score) as FSS (Functional Severity Scores) scores. Likewise, a significant improvement in nerve conduction was observed (p<0.05). In 43% of patients CTS could not be confirmed post-operatively. Except for post-operative pain and swelling around the operation site, no complications were observed. Interpretation: Extensive neurolysis of the median nerve in combination with perineural lipografting in repetitive recurrent CTS gives a significant long lasting improvement of symptoms with a low complication- and morbidity rate. This operative treatment seems promising and efficient for cases of recurrent CTS. Funding Statement: The authors stated that no funding was received for this article. Declaration of Interests: The authors have nothing to disclose. Ethics Approval Statement: This study was conducted in accordance with the declaration of Helsinki and approved by our medical research ethics committee (2016- 70).