An unusual cause of shoulder pain: osteoid osteoma of the acromion--a case report

Osteosarcoma in the coracoid process that mimicked an osteochondroma: A case report

RATIONALE

Osteosarcomas are the most common primary malignant bone tumors in children and young adults; these tumors often affect the metaphyses of long bones such as the proximal humerus, proximal tibia, and distal femur. In contrast, osteosarcoma of the coracoid process is extremely rare.

PATIENT CONCERNS

Herein, we describe a case of osteosarcoma affecting the coracoid process in a 40-year-old woman. The patient presented with shoulder pain, weakness, and an inability to raise her left arm. She had no previous record of shoulder injury and no significant family history.

DIAGNOSES

Her C-reactive protein levels were normal, whereas her erythrocyte sedimentation rate and alkaline phosphatase levels were elevated. Imaging studies led to the initial diagnosis of osteochondroma.

INTERVENTION

The patient underwent surgical resection. However, the postoperative pathological results revealed an osteosarcoma. The patient transferred to another hospital for subsequent treatment, and her outcome is unknown.

LESSONS

A misdiagnosis or inadequate and/or delayed treatment for a coracoid process osteosarcoma could have grave consequences. Computed tomography and magnetic resonance imaging are essential for a diagnosis, and a biopsy can effectively confirm the diagnosis. Our findings suggest that considering only a single factor, or using incomplete information, can lead to an arbitrary diagnosis.

Osteoid osteoma of the distal clavicle

The osteoid osteoma is a bone tumor that accounts for 10% of benign tumors. It was described in 1935 by Jaffe, as a tumor that affects the young adult population, with a predominance of males. This study aims to present a case of late diagnosis of a patient with osteoid osteoma of the distal clavicle region. Female patient, 44 years old, non-professional volleyball player, reported pain in the anterior and superior region of the shoulder girdle, specifically in the acromioclavicular joint, which worsened at night and had been treated for nine months as tendinitis of the rotator cuff and acromioclavicular joint arthritis. After confirming the diagnosis, the patient underwent open surgery with resection of the distal clavicle. At two years of follow-up, the patient presents without local pain. In the radiographic evaluation, coracoclavicular distance is preserved and there are no signs of recurrence. Tumors of the shoulder girdle are rare and are often diagnosed late. A high degree of suspicion for the diagnosis of tumors of the shoulder girdle is needed in order to avoid late diagnosis.

Osteoid osteoma of the acromion simulating acromioclavicular pain

The osteoid osteoma is a benign bone tumour that usually presents with nocturnal pain in young adults, relieved by rest and anti‐inflammatories. It can affect any bone; however, their occurrence is rare in the acromion. The authors describe a case of osteoid osteoma located in the acromion, with symptoms that simulated acromion claviculararthrosis. The diagnosis was made by CT scan and treatment was excision of the nidus through arthroscopy. The diagnosis was confirmed by histopathology. In the outpatient segment, the patient remained asymptomatic, with complete recovery of function of the affected limb.

Clinical applications of SPECT/CT in imaging the extremities

Today, SPECT/CT is increasingly used and available in the majority of larger nuclear medicine departments. Several applications of SPECT/CT as a supplement to or replacement for traditional conventional bone scintigraphy have been established in recent years. SPECT/CT of the upper and lower extremities is valuable in many conditions with abnormal bone turnover due to trauma, inflammation, infection, degeneration or tumour. SPECT/CT is often used in patients if conventional radiographs are insufficient, if MR image quality is impaired due to metal implants or in patients with contraindications to MR. In complex joints such as those in the foot and wrist, SPECT/CT provides exact anatomical correlation of pathological uptake. In many cases SPECT increases the sensitivity and CT the specificity of the study, increasing confidence in the final diagnosis compared to planar images alone. The CT protocol should be adapted to the clinical question and may vary from very low-dose (e.g. attenuation correction only), to low-dose for anatomical correlation, to normal-dose protocols enabling precise anatomical resolution. The aim of this review is to give an overview of SPECT/CT imaging of the extremities with a focus on the hand and wrist, knee and foot, and for evaluation of patients after joint arthroplasty.