[Non-traumatic myositis ossificans circumscripta in the teres major muscle].
A 49-year-old male presented with a painful progressive swelling in his right axillar region, without further complaints, which had been present for 2 weeks. On radiological examination a peripheral circumferential zone of mineralisation was seen in the right teres major muscle. An incision biopsy specimen showed a lesion of fibroblastic tissue in which areas of osteoid and fragmented lamellar bone tissue, without signs of malignancy. The diagnosis was myositis ossificans circumscripta. This is a rare benign ossifying lesion in skeletal muscles, mostly caused by a trauma and with an average age of occurrence between 20 and 30 years old. It must be differentiated from extra-skeletal osteosarcoma. The pathogenesis is unknown. Because it is a benign and self-limiting disorder, surgical excision is only necessary in case of mechanical hindrance. The patient's swelling partially regressed and he had no further complaints.
Afd. Inwendige Geneeskunde, Onze Lieve Vrouwe Gasthuis, 1e Oosterparkstraat 279, 1090 HM Amsterdam. j.e.arends@olvg.nl
J E
JE
Arends
P
P
Drillenburg
H J
HJ
van der Woude
K J
KJ
Roozendaal
B
B
de Valk
D001365:Axilla; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000473:pathology; D009221:Myositis Ossificans / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D012516:Osteosarcoma / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology