Evaluating Sensation Recovery in Noninnervated Free Flaps Used for Oral Reconstruction

Abstract

Association between time and sensation recovery in noninnervated flaps remains unclear. Our goal was to evaluate the recovery of sensation in noninnervated free flaps used for oral reconstruction. A prospective cohort study was designed and consecutive patients undergoing noninnervated free flap surgery for oral reconstruction from a tertiary medical center were enrolled. The primary outcome variable was sensory recovery of light touch, pain, hot, and cold temperature. Sensory recovery was scored as per the test on the central portion and 4 peripheral sections of every flap. The Kaplan-Meier method was used to estimate the functional recovery at different time points and the association between clinicopathologic variables and sensation recovery at 24months after surgery was analyzed using the chi-squared test and logistic regression analysis. Eighty patients were included with a median age of 50years. At 3months postoperatively, no patients exhibited sensation recovery. Positive flap sensitivity began to appear mildly at 6months postoperatively and gradually increased for at least 24months. The 24-month sensation recovery rates of light touch, pain, and temperature were 70.0% (95% confidence interval [CI]: 59.2 to 78.9%), 42.5% (95% CI: 32.3 to 53.4%), and 33.8% (95% CI: 24.45 to 44.6%), respectively. In univariate analysis, 80.5% (95% CI: 66.0 to 89.8%) of the free radial forearm flaps showed light touch sensation recovery, which was statistically higher than 59.0% (95% CI: 43.4 to 72.9%) in other flaps (P=.036). Flap size ≤ 65cm2 predicted better pain sensation recovery with 57.5% (95% CI: 42.2 to 71.5%) compared to 27.5% (95% CI: 16.1 to 42.8%) in flap size > 65cm2 groups (P=.007). Logistic regression analysis confirmed flap size ≤ 65cm2 (P=.032, odds ratio=1.957, 95% CI: 1.034 to 4.389) and not smoking (P=.015, odds ratio=2.564, 95% CI: 1.673-5.482) offered better sensation recovery of pain and hot temperature, respectively. Sensation recovery in noninnervated free flaps was common and related to not smoking and flap size.