Myositis ossificans

Inhibition of abnormal calcification initials explorations of BPs as inhibitors of calcification showed promise, and early applications of etidronate included use in myositis ossificans, as well as in patients who had undergone total hip replacement surgery, in order to prevent subsequent heterotopic ossification and to improve mobility [10]. 

Mutations also arise naturally during the manufacture of DNA. Thus, the opportunity for error exists every time a cell replicates. Even so, DNA is correctly made almost always. Predictably, cells that divide numerous times are more at risk for errors than cells that divide less frequently. For example, the egg cells are present in a female at birth and never undergo division, while sperm cells in males are constantly being produced. A theory proposes that the cause of birth defects including a type of dwarfism, Marfan syndrome, and myositis ossificans are typically the result of a defective gene contributed by a mutated sperm. 

Ackman JB, Rosenthal Dl. Generalized periarticular myositis ossificans as a comphcation of pharmacologically induced paralysis. Skeletal Radiol 1995 24(5) 395-7. 

Extraskeletal calcification occurs in several conditions unrelated to demonstrable abnormalities of calcium metabolism, such as scleroderma, myositis ossificans, calcinosis universalis, calcinosis cutis, and local tissue damage in the kidney. These disorders are not usually associated with changes in serum alkaline phosphatase (B30). Elevated values have, however, been reported in paraplegic patients with ectopic bone formation (F23), and a positive correlation has been demonstrated between the activity of serum alkaline phosphatase and the progression of this disorder. Nicholas (N4) claimed that hyperphosphatasemia in such a situation may help to differentiate thrombophlebitis, septic arthritis, and cellulitis from ectopic bone formation. 

CT is also helpful to follow fracture healing, particularly when mal or non-union (Fig. 3.2), myositis ossificans or pseudarthrosis development are suspected on plain radiographs. Those fractures involving the epiphyseal (growth) plates have the potential to interfere with later growth. Bone bridge formation and its consequent deformities are easy to illustrate with CT. 

Myositis ossificans occurs as a rare complication of muscle injury that is associated with a large haematoma. Typically, the lesion occurs in the adoles-... 

Fig. 4.22. Plain radiograph confirms the presence of myositis ossificans seen in Fig. 4.21...

Fig. 4.21. EFOV ultrasound demonstrates well defined ossification (arrowheads) in the vastus intermedius (VI) muscle, with posterior acoustic shadowing consistent with myositis ossificans...

Other less common complications include nonunion, radio-ulnar synostosis and myositis ossificans. 

There are three main complications of muscle tear cysts and myositis ossificans and, more rarely, calcific myonecrosis (Peetrons 2002). Intermuscular and intramuscular cysts may be encountered after muscle trauma as well-defined echo-free masses with posterior acoustic enhancement. These cysts have an elongated shape and represent the residue of a local hematoma. Their most common location is the calf (see Chapter 15). In selected cases, they may require percutaneous needle evacuation. Calcific myonecrosis is a space-occupying calcified mass that typically develops in the anterior compartment of the leg late after a closed lower extremity... 

Peck RJ, Metreweli C (1988) Early myositis ossificans a new echographic sign. Clin Radiol 39 586-588 Peers KHE, Brys PPM, Lysens RJJ (2003) Correlation between power Doppler ultrasonography and clinical severity in Achilles tendinopathy. Int Orthop 27 180-183 Peetrons P (2002) Ultrasound of muscles. Eur Radiol 1235-43... 

Schulte M, Mutschler W, Reiche W et al (1995) Diagnosis and spontaneous course of non-traumatic localized myositis ossificans. Unfallchirurgie 98 576-579... 

Thigh Pathology 622 Anterior Thigh 622, 1 Rectus Femoris Tears 622, 2 Vasti Muscle Tears 627, 3 Myositis Ossificans 628 Medial Thigh 629... 

Muscle tears can be followed by cystic transformation of the hematoma consisting of an ovoid fluid-filled anechoic cavity with well-defined margins located within the muscle (Fig. 13.28). A significant complication of vastus intermedius tears secondary to direct contusion trauma is myositis ossificans circumscripta, which is also referred to as heterotopic bone formation. This self-limiting condition starts with undefined chronic pain in the middle thigh... 

Fig. 13.30a,b Myositis ossificans, a Longitudinal 12-5 MHz US split-screen image obtained over the vastus lateralis muscle in a patient with a previous history of local blunt trauma with b radiographic correlation reveals multiple, irregularly shaped gross calcifications (arrows) within the vastus intermedius muscle. The vastus lateralis (open arrowheads) is displaced superficially by the bulk of the calcifications... 

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