An Unusual Presentation of Myositis Ossificans in a Pediatric Patient.
BACKGROUND
Myositis ossificans (MO) is a rare, non-neoplastic lesion characterized by heterotopic ossification of soft tissue. The condition is predominantly seen in young adults and adolescents and is most commonly secondary to trauma. Although the exact etiology remains unclear, patients typically present with pain and restricted range of motion following trauma or overuse. MO rarely presents in the popliteal fossa of adult patients and has not been previously reported in that of a pediatric patient.


METHODS
We present a 12-year-old patient with no history of direct trauma with MO in the right popliteal fossa, a highly unusual location. Initial x-rays failed to show the lesion; however, later radiographs showed an ossified mass. At peak dimensions, the ossification measured 3.8 cm anteroposterior×2.5 cm transverse×3.2 cm craniocaudal. After 14 months of observation and conservative therapy, the mass was excised.


RESULTS
The patient was ultimately able to return to full activity. Radiographs taken 14 months after the excision showed no signs of recurrence of the lesion.


CONCLUSIONS
To our knowledge, this is the first reported case of MO excised from the popliteal fossa of a pediatric patient and followed for >1 year.


METHODS
Level IV-case report.
*Department of Orthopaedic Surgery, University of Cincinnati †Department of Pathology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
Vishal S
VS
Desai
Rafael
R
Kakazu
Alvin H
AH
Crawford
Jerzy W
JW
Stanek
D002648:Child; D000072700:Conservative Treatment; D018450:Disease Progression; D005260:Female; D006801:Humans; D007717:Knee / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D008279:Magnetic Resonance Imaging; D009221:Myositis Ossificans / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D009999:Ossification, Heterotopic; D010146:Pain / Q000209:etiology; D010808:Physical Examination; D011859:Radiography; D016059:Range of Motion, Articular