J Korean Bone Joint Tumor Soc JKBJTS The Journal of the Korean Bone and Joint Tumor Society 1226-4962 2233-9841 The Korean Bone & Joint Tumor Society 10.5292/jkbjts.2012.18.2.89 Case Report Muscle Infarction and Calcification of the Semitendinosus Tendon: A Case Report Cho Jin-Ho Department of Orthopedic Surgery, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Korea. Correspondence to: Jin-Ho Cho. Department of Orthopaedic Surgery, Ilsan Paik Hospital, Inje University College of Medicine, 2240, Daehwa-dong, Ilsanseo-gu, Goyang 411-706, Korea. TEL: +82-31-910-9733, FAX: +82-31-910-7967, osd07@paik.ac.kr 12 2012 21 12 2012 18 2 89 93 27 04 2012 15 11 2012 19 11 2012 Copyright © 2012 by The Korean Bone and Joint Tumor Society 2012

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The most common anatomic location of calcific tendinitis is the suprasupinatus muscle of the shoulder joint. However, it is known to develop in any joint including the hip, knee. Infarction of skeletal muscle in the distal areas of the limbs due to vascular occlusion is a well recognized systemic condition in patients who have diabetes. The author experienced mass-like lesion combined muscle infarction and calcification within pure semitendinosus tendon without diabetes in posterosuperior area of distal thigh in old age.

 distal femur semitendinosus tendon muscle infarction calcification Uhthoff HK Sarkar K Maynard JA Calcifying tendinitis: a new concept of its pathogenesis Clin Orthop Relat Res 1976 118 164 168 Gärtner J Simons B Analysis of calcific deposits in calcifying tendinitis Clin Orthop Relat Res 1990 254 111 120 Baudrillard JC Lerais JM Segal P Enthesopathy of the upper insertion of the musculus rectus femoris. A retrospective sign of tendon rupture in sports pathology J Radiol 1986 67 185 191 Tennent TD Goradia VK Arthroscopic management of calcific tendinitis of the popliteus tendon Arthroscopy 2003 19 E35 Aboulafia AJ Monson DK Kennon RE Clinical and radiological aspects of idiopathic diabetic muscle infarction Rational approach to diagnosis and treatment J Bone Joint Surg Br 1999 81 323 326 Damron TA Levinsohn EM McQuail TM Cohen H Stadnick M Rooney M Idiopathic necrosis of skeletal muscle in patients who have diabetes. Report of four cases and review of the literature J Bone Joint Surg Am 1998 80 262 267 Lauro GR Kissel JT Simon SR Idiopathic muscular infarction in a diabetic patient. Report of a case J Bone Joint Surg Am 1991 73 301 304 Hinton A Heinrich SD Craver R Idiopathic diabetic muscular infarction: the role of ultrasound, CT, MRI, and biopsy Orthopedics 1993 16 623 625 Morcuende JA Dobbs MB Crawford H Buckwalter JA Diabetic muscle infarction Iowa Orthop J 2000 20 65 74

Lateral radiograph of right knee show calcified lesion (arrow) on posterior area of distal femur.

Magnetic resonance images shows well-defined soft tissue mass along semitendinosus tendon, posterior aspect of distal thigh. (A) T1-weighed image: slightly high signal intensity (B) T2-weighed image: heterogeneous iso signal intensity.

Gross examination reveals tendon (right white portion) with skeletal muscles (left cut view).

Microscopic findings of tendinitis with muscle infarct. (A) Low power view reveals tendon (T) and skeletal muscle (M) (×40). (B) Degeneration with infract (arrows) was noted in muscle portion (×200, H&E). (C) Degeneration with calcification (arrows) was noted in tendon portion (×100, H&E). (D) Tendinitis with foreign body reaction (arrows).