RESUMEN
PURPOSE: To assess the use of preoperative, dynamic ultrasound to predict ulnar nerve instability following in situ decompression for cubital tunnel syndrome. METHODS: Prior to undergoing in situ decompression, 43 consecutive patients underwent dynamic ultrasound to assess the stability of the ulnar nerve during elbow flexion. The dynamic ultrasound findings were compared with the intraoperative assessment of nerve stability following in situ decompression. RESULTS: The preoperative dynamic ultrasound agreed with intraoperative findings in 38 of 43 patients (88%). Physical examination of ulnar nerve stability agreed with the intraoperative findings in 5 of 43 patients (12%). For the 5 of 43 cases in which the dynamic ultrasound did not correlate with the degree of ulnar nerve stability after in situ decompression, dynamic ultrasound overestimated the degree of ulnar nerve stability in 4 cases. CONCLUSIONS: Preoperative dynamic ultrasound can be used to accurately predict the degree of ulnar nerve instability following in situ decompression. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.