Idiopathic aggressive myositis ossificans of the hand infiltrating the flexor sheath/checkrein ligament, obliterating the common digital artery, and attenuating the digital nerve: A case report

Idiopathic myositis ossificans of the deltoid muscle: A case report with unique presentation and MRI findings

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Myositis ossificans of the deltoid muscle is extremely rare.

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We present a case with unique presentation and MRI findings.

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Our case had no history of trauma or surgery in the area.

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Our case had MRI features mimicking myxoma.

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Complete excision was curative.

Introduction

Myositis ossificans of the deltoid muscle is extremely rare. We present a case with unique presentation and MRI findings.

Case Report

A 21-year-old female presented with a 3-month history of a swelling in lateral aspect of the right arm. There was no history of trauma, injection, or surgery to the area. Examination showed a 3 × 3 cm firm mass in the deltoid muscle. MRI findings were suggestive of myxoma. Surgical excision was done and histopathology showed the classic features of myositis ossificans. There was no recurrence at the final follow-up 7 months later.

Discussion

Myositis ossificans of the deltoid muscle is very rare with only 6 cases previously reported in the literature. Our case is unique in presentation because it is the first case reported with no history of trauma, Injection, sickness or surgery in the area. We also review the literature for MRI features of Myositis ossificans and show that our case has a unique pattern.

Conclusion

We report on a rare case of Myositis ossificans of the deltoid muscle and review of the literature for similar cases and MRI features of Myositis ossificans. We show that our case was unique both in presentation and MRI finding.