CT findings in a dog with subacute myopathy and later fibrotic contracture of the infraspinatus muscle

Abstract

A 5-year-old Norwegian elkhound was referred due to an acute onset of lameness and persistent shoulder pain over a period of 3 weeks. Computed tomography demonstrated an enlarged, hypoattenuating right infraspinatus muscle with peripheral contrast enhancement and a nonenhancing center, without concurrent lesions in superficial structures or bones. The right infraspinatus muscle showed progressive atrophy on consecutive CT studies. The dog developed clinical symptoms compatible with fibrotic infraspinatus contracture 2 months after the initial presentation, and was treated with infraspinatus tenotomy. Histopathological diagnoses based on intraoperative biopsy samples were fibrotic muscle atrophy and muscle hypertrophy with regeneration.

Keywords: canine; compartment syndrome; infraspinatus necrosis; myopathy.