Reducing Trismus After Surgery and Radiotherapy in Oral Cancer Patients: Results of Alternative Operation Versus Traditional Operation

Abstract

In patients with oral cancer, trismus (maximum interincisal opening [MIO] <35mm) can develop as a result of surgery and radiotherapy. The aim of this study was to provide an alternative operation to both eradicate oral cancer and prevent postsurgical trismus. In our retrospective cohort study of oral cancer patients who underwent operations during 2010 to 2014, the predictor variable was the type of operation (alternative operation or traditional operation) and the outcome variable was MIO. All of the cases were allocated by 2 periods: the traditional operations were performed from 2010 to 2011, and the alternative operations were performed from 2011 to 2014. All patients received marginal mandibulectomy, anterolateral thigh free flap, and adjuvant radiotherapy or concurrent chemoradiotherapy. In addition to traditional marginal mandibulectomy, the alternative operation included ipsilateral coronoidectomy and myotomy of the temporalis muscle insertion, masseter muscle, and medial pterygoid muscle. MIO was measured at 10 time points. The adjusted variables included demographic data, diagnostic parameters, treatment, and response. Of the 36 male patients with oral cancer, 16 were placed in the alternative operation group (AOG; mean age, 53.5 ± 11.9years) and 20 were placed in the traditional operation group (TOG; mean age, 50.7 ± 7.1years). Regarding the outcome indicator of patient MIO, the preoperative MIO in the AOG was on average 7.5mm shorter than that in the TOG (P < .01), but it was consistently superior to the MIO in the TOG after the operation. Multivariate analysis of variance showed that patients in the AOG were more likely to have postoperative non-trismus. The alternative operation exhibited superior postoperative MIO values and similar postoperative complication rates. For the prevention of trismus, it is practical to perform the combined operation simultaneously, cutting all ipsilateral jaw closing muscles and the coronoid process and eradicating the tumor.