Shoulder function after selective and superselective neck dissections: clinical and functional outcomes

The aim of this work is to assess the clinical and functional outcome of patients who underwent different types of neck dissection, with special regards to the spinal accessory nerve, trapezius muscle and shoulder function. From February 2008 to July 2010, we evaluated 17 cases of neck dissection in patients affected by laryngeal carcinoma clinically staged N0. We performed selective neck dissection (IIA-IIBIII- IV) in 11 cases (group A) and superselective neck dissection in 6 cases (group B). All patients underwent clinical examination before surgery to evaluate shoulder function. They also underwent functional evaluation of the spinal accessory nerve through electromyography (study of muscular activity) and electroneurography (study of motor action potential). Patients were evaluated before surgery (T0), 8 days after surgery (T1) and 21 days after surgery (T2). In all cases, at the end of surgery it was possible to assess the integrity of the spinal accessory nerve. The average value of the MAP was 13.06 in group A and 10.98 in group B at T0. Eight days after surgery (T1) the value of MAP was reduced to 1.35 in group A and 6.15 in group B. Electromyography evaluation showed signs of denervation in 6 cases in group A and in 2 cases in group B. Voluntary activity was not detectable in 6 cases in group A, while it was present, even if reduced, in all cases in group B. At 21 days after surgery (T2), we found a value of MAP of 1.03 in group A and 6.43 in group B. Electromyography showed signs of denervation in 10 patients in group A and in 3 cases in group B. Voluntary activity was not detectable in 10 cases in group A, while it was present in all cases in group B. The arm abduction test was 2.5 in group A and 4.0 in group B. Neck dissection quality of life questionnaire showed a value of 24.17 in group A and a value of 25.5 in group B. Our data thus confirm that surgical manipulation of the nerve may be associated with severe impairment of nerve conduction when sublevel IIB is involved in the dissection.