return to: Selective Neck Dissection

see also: Calcific Tendonitis of Longus Colli

History

Onset of pain in neck with increasing firm mass following a snowmobile accident with trauma to the left neck. This mass had shown a gradual increase in size, but tapering as to the rapidity with which it had been enlarging - but still associated with an increase in pain. The pain was first noted with the appearance of the mass - with her first discovery including shooting pains down her arms, which she ascribes to the region of the bone.

Evaluation suggested myositis ossificans with options for treatment discussed including risk of recurrence.

Surgical approach

Resection of heterotopic bone

Modified operative note

A horizontal incision was made in a skin crease in the patient's left lower neck just above the clavicle. The incision was carried down through the platysma and a subplatysmal flap raised superiorly. The Parsons-McCabe nerve stimulator was used to identify the trapezius branch of the spinal accessory nerve. Dissection was done on the nerve to verify that it was cephalad to the heterotopic ossificans and not involving the mass. Dissection was done down to the heterotopic ossificans, and the mass then removed by the Orthopaedic team after dissection on the capsule surrounding the mass. The mass was passed off for a specimen and the wound was irrigated with copious amounts of sterile saline. The wound was then closed with deep 4-0 Monocryl and a subcutaneous running 4-0 Monocryl.

Followup 14 months later identified relief of pain for 11 months with slight discomfort for the past 3 months with concern about possible regrowth with plain film xrays negative

Discussion

The underlying pathophysiology of myositis ossificans is poorly understood, and its presentation can mimic other pathologies such as a soft-tissue abscess, a soft-tissue sarcoma, or rarer conditions such as reactive periostitis (Walczak et al. 2015). The classical clinical presentation is a younger male patient who is an athlete and had a precipitating blunt force trauma trauma to a soft tissue, with the underlying inflammatory reaction and pain never fully resolving. The initial inflammatory reaction can last approximately 4 weeks, which will precede ossification. Then, in the intermediate phase approximately 4-8 weeks after intial trauma, calficiations will become apparent on radiology (Folpe et al.) Thereafter, the lesion matures, and is typically either clinically stable or will spontaneously regress.

Typical locations for myositis ossificans includes the flexor surfaces of the arms and the extensor surfaces of the thighs. However, patients can present with lesions in atypical locations, including distally in the hands in feet, or in the neck as in the patient case presented above (Nuovo et al. 1992). Laboratory testing can be helpful in the initial stages, and may show an elevated serum alkaline phosphatase level and an elevated creatitine phosphokinase level, however the gold standard testing modality is through an MRI (Garland 1991, Singh et al. 2003).

Lesions consistent with myositis ossificans will demonstrate different findings depending on the stage of the lesion. In the acute setting, lesions will appear similarly to a hematoma, with T1-weighted images showing areas of heterogeneous signal intensity consistent with blood products. T2-weighted images can show areas of hypodensitiy which may represented areas of hemosiderin deposition or calcifications (Lacout et al. 2012). Later in the disease progression, T1-weighted images will show lesions isointense or slightly hypointense to surrounding skeletal muscle, with possible surrounding edema. 

Myositis ossificans can be managed nonsurgically with conservative measures such as rest, ice, compression, and elevation to minimize hematoma size and resulting inflammatory reaction. Additionally, physical therapy can aid in improving joint mobility and strength (Lipscomb et al. 1976). However, in lesions that do not resolve, or in lesions that compromise surrounding neurovascular structures, surgical management may be indicated. In these cases, marginal excision is typically sufficient, however there have been reported cases of recurrence. 

References

Walczak, B. E. , Johnson, C. N. & Howe, B. M.  (2015).  Myositis Ossificans. Journal of the American Academy of Orthopaedic Surgeons,  23 (10),  612-622.  doi: 10.5435/JAAOS-D-14-00269.

Folpe AL, Gown AM: Cartilaginous and osseous soft tissue tumors, in Goldblum JR, Folpe AL, Weiss WS , eds: Enzinger & Weiss’s Soft Tissue Tumors, ed 

Nuovo MA, Norman A, Chumas J, Ackerman LV: Myositis ossificans with atypical clinical, radiographic, or pathologic findings: A review of 23 cases. Skeletal Radiol 1992;21(2):87–101.

Garland DE: A clinical perspective on common forms of acquired heterotopic ossification. Clin Orthop Relat Res 1991;263:13–29.

Singh RS, Craig MC, Katholi CR, Jackson AB, Mountz JM: The predictive value of creatine phosphokinase and alkaline phosphatase in identification of heterotopic ossification in patients after spinal cord injury. Arch Phys Med Rehabil 2003;84(11):1584–1588.

Lacout A, Jarraya M, Marcy PY, Thariat J, Carlier RY: Myositis ossificans imaging: Keys to successful diagnosis. Indian J Radiol Imaging 2012;22(1):35–39.

Lipscomb AB, Thomas ED, Johnston RK: Treatment of myositis ossificans traumatica in athletes. Am J Sports Med 1976;4(3):111–120.