Published online by Cambridge University Press: 15 August 2017
Non-traumatic bone fractures in cancer patients are usually pathological fractures due to bone metastases. In head and neck cancer patients, clavicle stress fractures may occur as a result of atrophy of the trapezius muscle after neck dissection in which the accessory nerve becomes structurally or functionally damaged.
A 71-year-old man underwent modified radical neck dissection with accessory nerve preservation and post-operative radiotherapy for submandibular lymph node metastases of tongue cancer. Four weeks after the radiotherapy, a clavicle fracture, with osteomyelitis and abscess formation in the pectoralis major muscle, occurred. Unlike in simple stress fracture, long-term antibiotic administration and drainage surgery were required to suppress the inflammation.
As seen in the present patient, clavicle stress fractures may occur even after neck dissection in which the accessory nerve is preserved, and may be complicated by osteomyelitis and abscess formation owing to risk factors such as radiotherapy, tracheostomy and contiguous infection.