Frey's syndrome after superficial parotidectomy: role of the sternocleidomastoid muscle flap: a prospective nonrandomized controlled trial

Abstract Background The prevalence of Frey's syndrome (FS) after superficial parotidectomy in correlation to the sternocleidomastoid muscle flap (SCMMF) interposition is analyzed. Methods A prospective nonrandomized controlled multicenter trial included 130 patients. During superficial parotidectomy, SCMMF was dissected, if excised specimens' volume exceeded 25 mL (SCMMF group). Follow-up examinations took place after 6, 12, and 24 months and included a Minor's test. Results SCMMF was dissected in 30 (23.1%) patients. A total of 104, 80, and 68 patients completed the 1st, 2nd, and the 3rd follow-up, respectively. FS was detectable with nonvarying prevalence (46.3%, 45.6%, and 43.4%, respectively) during follow-up. The prevalence was higher in the SCMMF group (59.9%) than in the non-SCMMF group (41.8%; P = .92). The sweating area increased during follow-up ( P = .12). Overall, 89.5% of patients characterized FS as not disturbing after 2 years. Conclusions FS occurred with a steady and high prevalence after superficial parotidectomy. In particular, SCMMF did not lower the risk of FS.