104 - Calcific tendinitis of the conjoint tendon secondary to heterotopic ossification: A case report highlighting the utility of dynamic diagnostic musculoskeletal ultrasound

Thursday, February 19, 2026

5:00 PM - 6:30 PM AST

Presenting Author(s)

MB

Matthew J. Bennett, MD

Resident Physician
LSUHSC New Orleans
Metairie, Louisiana, United States

Co-Author(s)

AJ

Annelise Juneau, BSc

Medical Student
Louisiana State University Health Science Center- New Orleans
New Orleans, Louisiana, United States
RO

Robert P. Owens, MD

Residency Program Director
Louisiana State University School of Medicine
Candler, North Carolina, United States

Submitter(s)

MB

Matthew J. Bennett, MD

LSUHSC New Orleans
Metairie, Louisiana, United States

Case Diagnosis: Calcific tendinitis of the conjoint tendon secondary to heterotopic ossification

Case Description: A 40-year-old male veteran with bilateral transfemoral amputations following an improvised explosive device injury presented with right buttock pain, popping, and grinding during prosthetic use. Examination showed tenderness over the ischial tuberosity. Imaging revealed bandlike heterotopic ossification in the region. Using diagnostic musculoskeletal ultrasound with dynamic assessment, a mobile osseous fragment causing impingement and calcific tendinitis at the hamstring origin was identified. Orthopedic consultation was arranged for possible surgical excision.

Discussions: Heterotrophic ossification (HO) refers to pathological formation of ectopic bone within soft tissues and is a well-recognized complication of traumatic amputations. HO may present with pain, swelling, and prosthetic intolerance, limiting functional rehabilitation. Mild cases may be managed with conservative measures; however, when HO becomes symptomatic or functionally limiting, surgical excision is indicated to alleviate pain and improve prosthetic function and fit. Early recognition and management are key in mitigating its impact on post-amputation rehabilitation outcomes. Dynamic musculoskeletal ultrasound is increasingly recognized for its diagnostic utility in detecting impingement syndromes, with studies demonstrating high sensitivity and correlation with MRI in conditions such as femoroacetabular and ischiofemoral impingement. In this case, ultrasound provided real-time identification of heterotopic ossification-associated impingement contributing to the patient’s symptoms, which was not clear on static imaging modalities. The ability to assess pathology dynamically and in-clinic allowed for prompt diagnosis and surgical referral.

Conclusions:

Dynamic diagnostic musculoskeletal ultrasound can enhance the physiatric examination. In this case, it identified mobile HO at the ischial tuberosity causing painful impingement and calcific tendinitis, prompting surgical evaluation.