Introduction

Osteoid osteoma is a small, benign, and painful tumor most commonly affecting the extra articular portions of the long bones, especially the femur or tibia. Osteoid osteoma of the clavicle is so rare that we found only five previously reported cases in the international literature._{1 2 3 4} We described the investigations and conservative management of a case of osteoid osteoma in this unusual location.

Case report

An 18 years old female girl, Eastern Terai district of Nepal, presented in the Orthopaedic Out Patient Department with complaints of pain and swelling on the right clavicle of two and half years duration. She did not give history of trauma, and constitutional symptoms. There was full range of movement of the right shoulder. There was no evidence of infections at the site. X-ray revealed radio-density of whole of the clavicle except lateral tip of the clavicle (Fig A & B).

Figure 1

Figure A: Radiodense Right Clavicle

Figure 2

Figure B: Comparison between clavicles

CT scan revealed radio-dense clavicle with obliteration of the medullary canal. Core biopy of the clavicle was done to obtain the specimen. Histopathological examination confirmed the diagnosis of the osteoid osteoma of the clavicle by doing core biopsy of the clavicle. Patient was kept on Aspirin tablets 375 mg three times a day for 6 weeks, and symptomatically improved in terms of pain and swelling. At the end of 3 months follow up, patient had pain free with subsidence of swelling without fresh complaints.

Discussion

Sclerosing lesion of clavicle as Osteitis condensans, Condensing osteitis, Hypertrophic osteitis of the clavicle have been reported in the international literature. But Osteoid osteoma of the clavicle is rare as per the literature search using mesh words osteoid osteoma of clavicle. Therefore the histopathologically proven case of Osteoid osteoma of clavicle is presented with literature search. In this case medical management cures the patient.

Lepore L et. al describe a case of osteoid osteoma of the clavicle in an Olympic free-style wrestler who presented to us with persistent and increasingly elevated pain in his right shoulder. Originally a persistent injury was considered to be causing the pain, however, the correct diagnosis was made three months after the onset of the symptoms. Even in sportsman where muscle pain is commonplace, non-traumatic conditions should be considered in the presence of persistent and increasingly elevated pain that is not relieved by rest and physiotherapy.₄

Condensing osteitis of the clavicle is a benign disorder leading to osteosclerosis of the medial end of the clavicle. The differential diagnosis between condensing osteitis of the clavicle and ischaemic necrosis of the medial clavicular epiphysis (Friedrich's disease), osteoid osteoma, and low grade osteomyelitis can be difficult. In the case history reported here, magnetic resonance imaging was a useful non-invasive procedure for the diagnosis of condensing osteitis of the clavicle.₅ Condensing osteitis of the clavicle is a benign, often painful disorder, marked by bony sclerosis at the sternal end of the clavicle. It can be mistaken for other abnormalities such as Friedrich disease, bone island, osteoid osteoma, sternoclavicular osteoarthritis, and even a metastasis and osteosarcoma. Clinical, radiologic, scintigraphic, and histologic features of this condition are discussed and a brief overview of the treatment is provided. Three histologically proved cases are added to the 13 previously reported in the literature. Recognition of condensing osteitis of the clavicle may avoid the occasional unnecessarily aggressive diagnostic approach taken to search for a malignant tumor.₆

Correspondence to

Dr Suraj Bajracharya MBBS, MS (Orthopaedics) Department of Orthopadics B P Koirala Institute of Health Sciences Dharan E-mail: drsurajbajra@hotmail.com