Myofascial pain syndrome after head and neck cancer treatment: Prevalence, risk factors, and influence on quality of life.
BACKGROUND
Patients undergoing treatment for head and neck cancer may develop myofascial pain syndrome as sequelae. The purpose of this study was to determine the prevalence, risk factors, and quality of life (QOL) related to myofascial pain syndrome.


METHODS
This was a prospective study including patients with head and neck cancer with at least a 1-year disease-free interval.


RESULTS
One hundred sixty-seven patients were analyzed, and myofascial pain syndrome was diagnosed in 20 (11.9%). In the multivariate analysis, hypopharyngeal tumors (odds ratio [OR] = 6.35; 95% confidence interval [CI] = 1.58-25.56) and neck dissection (OR = 3.43; 95% CI = 1.16-10.17) were independent factors for myofascial pain syndrome. The pain (p < .001) and shoulder domain (p < .001) as well as overall University of Washington Quality of Life (UW-QOL) score (p = .006) were significantly lower in the patients with myofascial pain syndrome.


CONCLUSION
Myofascial pain syndrome was observed in 1 of 9 patients after head and neck cancer treatment and a worse QOL was observed among them. Tumor site and neck dissection were found to be risk factors for myofascial pain syndrome.