Background: Patients undergoing revision surgical treatment of the ulnar nerve at the elbow for cubital tunnel syndrome (CuTS) will have worse results compared to patients successfully treated with primary surgery.Objective: The purpose of this study is to evaluated clinical outcomes of revision neurolysis and ulnar groove plasty for recurrent and persistent cubital tunnel syndrome after failed surgical treatment.Methods: This retrospective investigation included patients presented with recurrent and persistent CuTS who were treated surgically with combination of revision neurolysis and ulnar groove plasty at a single institution from May 2006 to Oct 2016 with postoperative follow-up more than 24 months. Demographic data of all patients including age, sex, months to revision surgery, presenting symptoms after index surgery, previous surgical procedure and intraoperative findings were all recorded and pre-operative and post-operative data were compared. McGowen grading was used to evaluated functional impairment before and after revision surgery.Results: There were 28 patients were identified with recurrent and persistent CuTS after primary surgery and 21 patients (75%) were completed in this study with an average age was 56 years, mean duration of symptoms was 17.24 months, and mean postoperative follow-up was 35.38 months. 17 patients had McGowan stage III and 4 had stage II preoperatively. The most common cause of recurrent and persistent CuTS was perineural fibrosis with or without kink which accounts for 86.36% according to intraoperative findings. McGowan grading improved after revision neurolysis and ulnar groove plasty is 80.95%. Improvement of Visual Analogue Scale (VAS) and 2-point discrimination test were 81.25% and 85.71%, respectively. Patients satisfaction after revision neurolysis and ulnar groove plasty was 95.24%.Conclusion: The favorable results of this study demonstrated that revision neurolysis and ulnar groove plasty as the treatment of choice for recurrent or persistent cubital tunnel syndrome. [ABSTRACT FROM AUTHOR]