Operative management of idiophatic myositis ossificans of lateral pterygoid muscle

Abstract

INTRODUCTIONMyositis ossificans (MO) is characterized as heterotopic bone formation within muscle. MO rarely occurs in the head and neck region. Excision of the heterotopic bone is the standard treatment. This report summarizes a case of a 12-year old female with MO involving the lateral pterygoid muscle. The heterotopic bone was excised using an intraoral incision. Despite intensive physical therapy, the operation failed as evidenced by new bone formation in the area within three weeks of the operation.PRESENTATION OF CASEA twelve years old female patient presenting with mouth opening of 10 mm, no facial asymmetry, and no jaw joint pain or other symptoms. Computer tomography (CT) exam was requested and revealed calcification of the left lateral pterygoid muscle. No other masticatory or head muscles showed any signs of calcification. The calcified muscle was completely removed beyond the ossified segment and a 35 mm mouth opening was achieved immediately after the procedure. One month after total bone structure removal (first surgery) the patient could not open her mouth anymore due to a significant calcified mass.DISCUSSIONThe surgical technique used in this case avoided invasive gap arthroplasty to access lateral pterygoid muscle and anaesthetic scarring formation, by using an intraorally incision accessing the muscle directly.The authors of these study did not see any relation with the condylar dislocation that the patient had five years prior to the pathology, and they could not find any real cause for the myositis ossificans of lateral pterygoid muscle.CONCLUSIONThe outcome of the surgical procedure was not successful, perhaps due to the expression of the disease, indicating the need to further physiologic and genetic studies to elucidate the aetiology of MO as well as to provide directions to an adequate treatment choice for such cases.

Myositis ossificans traumatica of the masticatory muscles: etiology, diagnosis and treatment

“…In addition to excision, − with or without physical therapy, the use of interpositional materials [ 12 , 16 , 17 , 20 , 28 ] or pharmaceuticals, such as etidronate or ibuprofen [ 29 ] have been proposed. Often, these additional measures were applied in clinical cases with multiple recurrences [ 11 , 14 , 16 , 17 , 30 ] so that the benefit of additional treatment cannot be assessed conclusively.…”

Myositis ossificans of the masseter muscle: A rare location. Report of a case and review of literature

“…MOP is an autosomal dominant genetic disease with variable expression and penetrance in which multiple heterotopic ossification develop systemically in various muscles, fascia, tendons and ligaments of the body. MOT has a good prognosis after a surgical treatment against MOP that produces a decreased survival due to respiratory muscles affection, and its predominance in teenagers or younger ( 1 , 6 , 7 ).…”

“…On the other hand, about a third of cases resolve spontaneously, so it could be considered an expectant attitude ( 1 ). Some articles defend the use of interpositional materials, such as abdominal or buccal fat pads, with the aim of prevent relapse, hematoma or collapse after excision ( 1 , 6 ). Other authors have proposed a complementary treatment with drugs such as etidronate disodium -a biphosphonate commonly used as a prophylaxis and treatment of Paget’s disease which prevents aggregation, growth and calcification of crystals ( 4 , 7 )-, nonesteroidal anti-inflammatory drugs, steroids, warfarin –a inhibitor of vitamin K products that reduces the production of osteocalcin which plays a significant role in metabolic regulation ( 1 , 6 , 11 )-, and low-dose radiation.…”

Myositis ossificans: A rare location in the foot. Report of a case and review of literature

“…The majority of the patients are male. The lesions are predominately involves the high-risk sites of injury in about 80% of cases, such as thigh, elbow and buttocks [5] . The most commonly affected sites in the lower extremity are the quadriceps femoris and gluteus muscles, and those in the upper extremity are the brachialis muscle [4] .…”