[Non-traumatic myositis ossificans circumscripta]

Myositis ossificans circumscripta of the thigh: A pediatric case report

Circumscribed myositis ossificans is a benign process of focal heterotopic ossification of the soft tissues, occurring in young subjects, usually following trauma. We report a case of a 15-year-old patient who suffered a direct trauma to the thigh during a soccer match, and developed a hard mass in the anterior face of the thigh. The patient was diagnosed with myositis ossificans secondary to trauma. In this case report, we want to illustrate the different imaging aspects of this benign condition, both in conventional radiology, computed tomography and magnetic resonance imaging, as its clinical and radiological appearance can be misleading, suggesting a sarcomatous neoplastic process.

Aneursymal Bone Cyst: An Uncommon Paraspinal Tumor in Children

Paraspinal tumors with benign histology in the absence of trauma rarely arise in children. Treatment of such benign tumors, in contrast to malignancies, generally consists of surgical resection of the lesion with confirmation of histology via pathologic evaluation. We present a pediatric case of an atraumatic paraspinal mass with a histologic diagnosis of aneurysmal bone cyst, and USP6 gene rearrangement supporting the histologic diagnosis. The patient underwent gross total resection of the paraspinal lesion with no additional intervention. We highlight the differential diagnosis of paraspinal tumors in children and key features that led to the diagnosis in this patient.

[Myositis ossificans circumscripta, an unusual location: about a case and review of the literature]

Myositis ossificans circumscripta (MOC) is a rare condition characterized by nontumoral heterotopic ossification of the soft tissues. This condition affects young subjects, occurring mainly after trauma. It is ubiquitous, predominantly located in girdles and limbs. We report the case of a young patient with paravertebral MOC without traumatic context; the aim of this study was to recall diagnostic criteria and imaging aspects.

Non-traumatic myositis ossificans circumscripta: A diagnosis trap

Myositis ossificans circumscripta (MOC) is a benign condition of non-neoplastic heterotopic bone formation in the muscle or soft tissue. Trauma plays a role in the development of MOC, thus, non-traumatic MOC is very rare. Although MOC may occur anywhere in the body, the lesions are localized predominantly in the high-risk sites of injury, such as the thigh, buttock, and elbow. MOC can easily be mistaken for osteomyelitis or a malignant tumor, specifically osteosarcoma or soft-tissue sarcoma. We report a rare case of non-traumatic myositis ossificans circumscripta of thigh which appear clinically and radiologically as a malignant neoplasm. Despite its rarity, MOC should be contemplated in the differential diagnosis of malignant tumors.

Myositis ossificans circumscripta of the triceps due to overuse in a female swimmer

Myositis ossificans is a rare condition characterized by non-neoplastic heterotopic bone formation in soft tissue and skeletal muscle. It is a benign and often self-limiting disease with no need for surgery. Here, we describe a young female swimmer with myositis ossificans circumscripta of the triceps due to overuse. Because of the benign character of the lesion, conservative treatment was initiated with rest and anti-inflammatory drugs. She obtained complete resolution after 6 months and was able to return to normal sporting activities. Myositis ossificans circumscripta is a rare benign lesion with an excellent prognosis. Most lesions in athletes occur due to contusions or strains; however, overuse is now described as well. Spontaneous resolution is seen in almost all cases. Cases in which, despite conservative treatment, a painful mass persists, surgical excision can be considered.

FDG PET/CT findings in a case of myositis ossificans circumscripta of the forearm

Myositis ossificans circumscripta (MOC) is a rare benign neoplasm located in soft tissues that, most of the time, appears after a local trauma. The positive diagnosis of MOC may be challenging on CT or MRI findings. We report on an atypical case of a spontaneous nontraumatic MOC in a 54-year-old man, located in the longus supinatus muscle diagnosed with MRI and F-18 FDG PET/CT findings. Rarely described F-18 FDG PET/CT features in MOC are presented. Pattern of avid FDG focus on PET/CT, that may wrongly suggest osteosarcoma, is presented.

La myosite ossifiante circonscrite: à propos d’un cas

Myositis ossificans circumscripta is a benign lesion characterized by focal heterotopic soft tissue ossification, occurring in young people generally after localized trauma. Clinical and radiological appearances may mimic a sarcomatous neoplastic process. We report a case of myositis ossificans occurring after trauma, so as to illustrate the different imaging features of this benign pathology on conventional radiographs and computed tomography.

Imaging of sports-related muscle injuries

Muscle derangements in athletes have a wide variety of causes, treatments, and prognoses. Given that the cause and severity of sports-related injuries may be difficult to determine clinically in some cases, MR imaging is utilized increasingly to evaluate muscle injuries in athletes. After reviewing useful MR imaging techniques, this article focuses on MR imaging of the most common causes of muscle pain and disability in athletes, including myotendinous strain, delayed onset muscle soreness, muscle contusion, myositis ossificans, muscle laceration, muscle herniation, and compartment syndrome. The differential diagnosis of various signal intensity abnormalities in muscle also is reviewed.

Traumatic myositis ossificans (ossifying pseudotumor) of temporal muscle

The purpose of this paper is to present the clinical, radiographic, and histological aspects of a case of traumatic myositis ossificans of the temporal muscle. This is a rare, benign ossifying pseudotumor of skeletal muscles. It had developed 3 weeks after trauma to the left temple in a 33-year-old man. Differential diagnostic aspects of traumatic myositis ossificans confirming its benign character are discussed.

[Myositis ossificans circumscripta and sequelae of muscular ischemia. 2 cases]

INTRODUCTION

Non-traumatic myositis ossificans circumscripta is a relatively rare, well defined entity. The pathogenic role of ischemia in its development is discussed.

EXEGESIS

We report two cases of myositis ossificans circumscripta that occurred in the hamstring muscle respectively 22 and 35 years after ischemic muscular injury in the same site. Clinical and radiologic informations and follow-up were reexamined, showing that patients are usually young and that the disease is equally distributed between both genders. Though the lesion may develop in various muscle, it is preferentially observed in proximal sites. Most patients have a history of localized pain or tenderness accompanied by swelling of the affected site. Following a 5- to 12-week increase, the soft-tissue mass is less sensitive and better defined. It may also resolve in less than 3 years.

CONCLUSION

Results of X rays, computerized tomography, MR imaging and biopsy are reviewed. Histologically, this lesion main feature is peripheral bone maturation within three areas. Mechanisms (traumatic or not) underlying these lesions are unknown. To our knowledge, only one published case would be comparable to ours. Proliferation followed by change in mesenchymal cells leading to heterotopic ossification must be regarded as a consequence of either ischemia or repeated micro-trauma occurring during muscle shortening.