The Elbow

Am J Sports Med

Myositis ossificans of the upper arm.

Huss CD, Puhl JJ

Myositis ossificans is a benign condition resulting from severe muscular contusion manifested
by heterotrophic bone formation.
The process is common in the anterior thigh but the literature dealing with myositis
ossificans in the upper arm is limited. Ten cases of the condition in the
upper arm were seen in our practice.
All 10 were the result of football injuries and exhibited one or more of the triad
of local pain, a hard palpable mass in the muscle, and a flexion contracture of the elbow.
Seven of the cases (70%) were asymptomatic or signficantly improved in less than 3
months with conservative nonoperative management.
Three patients (30%) underwent surgery because the painful mass persisted.
In two (66%) of the surgically managed cases, there was clinical and radiographic evidence
of recurrence postoperatively in spite of delaying excision until radiographic parameters
of maturation were present.

Clin Orthop

Pathogenesis of experimental heterotopic bone formation following
temporary forcible exercising of immobilized limbs.

Michelsson JE, Rauschning W

In rabbits, repeated passive forcible exercising of immobilized hip, knee, ankle, or elbow
joints produced muscle necrosis within a few days.
Within two to five weeks, heterotopic cartilage and bone formation occurred in the soft
tissues around the joint and in the area of damaged muscle.
The changes were morphologically and radiographically similar to those observed in human
myositis ossificans.
The incidence of these changes was correlated with the duration of immobilization and
the frequency of manipulation.
Ossification occurred especially in muscle attachments to bone. Denervation, administration
of diazepam, or narcosis during manipulation did not prevent the development of heterotopic bone.
Treatment by passive manipulation, immobilization, crushing the muscles, or repeated injections
of autogenous blood into the muscles did not induce significant calcification.
Heterotopic bone formed as a consequence of repeated forcible distention of previously
immobilized soft tissues.

Copyright © 2021 DR. L. OMBREGT All Rights Reserved
The author can not be held responsible for any damage caused by the use of any information provided.