Osteochondroma of Dorsal Scapula: A Case Report and Review of Literature

Abstract

Introduction: Osteochondroma of the scapula constitutes only 3-5% of all osteochondromas; osteochondroma on dorsal aspect of scapula is a rare entity. Diagnosis is almost always clinicoradiologically. Additional computed tomography scan and magnetic resonance imaging may be required for osteochondroma of flat bones such as scapula. Indications for surgery include pain, deformity, dysfunction, neural or vascular compromise, failure of conservative management, or in clinical settings with the high suspicion of malignant transformation and occasionally cosmesis. Outcome of a surgery should be assessed by Patient-Reported Outcome Measures (PROMs) which appraises what "matters to the patient."

Case report: A 10-year-old boy presented to us with painless swelling over the right upper back since 3 years of age and discomfort over the area while sleeping on his back for 6 months. Diagnosis confirmed it to be a pedunculated osteochondroma arising from the dorsal scapula. Here, we report the diagnosis, treatment, and successful Patient-Reported Outcome using QuickDASH© score for an osteochondroma of dorsal scapula using CARE© case reporting guidelines.

Conclusion: We report a rare site of osteochondroma, review the relevant literature, and also stress upon the necessity of analyzing PROMs after surgical treatment of benign tumors of bone which would enable us to evaluate the result of surgery on symptoms, functioning, and health-related quality of life from the patient's perspective.

Keywords: Osteochondroma; Patient Reported Outcome Measure; Patient-Reported Outcome; osteocartilaginous exostosis; scapula.

Figure 1

Clinical pictures of the patient shows the swelling on the dorsal aspect of right lower scapula.

Figure 2

X-ray of right shoulder AP and scapular Y-view shows osteochondroma arising from the dorsal surface of lower end of right scapula measuring 4.9 cm × 3.3 cm.

Figure 3

Magnetic resonance imaging shows a bony outgrowth arising from the infraspinatus fossa of the lower end of right scapula measuring 4.8 cm × 4.1 cm × 3.4 cm (mediolateral × anteroposterior × cephalocaudal) with overlying cartilage cap measuring up to 4.6 mm in thickness with no edema within the tumor and no development of bursa around the growth. The overlying muscles appear compressed.

Figure 4

Intraoperative image of the tumor exposed during surgical dissection.

Figure 5

Histopathologic examination after decalcification shows multilobulated neoplasm composed of fibrous capsule formed by benign chondrocytes in columnar arrangements. The base shows endochondral ossification. Maximum thickness of cartilage cap is 5 mm. Fatty cells and hemorrhagic marrow material are seen between the bony trabeculae of the stalk. No spindle cells/nuclear pleomorphism/ abnormal mitosis are seen. Morphological features are consistent with Exostosis/osteochondroma.

Figure 6

Post-operative picture of a completely healed surgical scar at 2 weeks.