The Diagnostic Challenge of Osteoid Osteoma in the Bones of the Hand-A Case Series

Abstract

Osteoid osteoma (OO) is a benign bone tumor that rarely occurs in the bones of the hand. Due to the comparatively non-specific symptoms when occurring in the hand, OO is often misdiagnosed at first presentation, posing a diagnostic challenge. In the present case study, six cases of phalangeal and carpal OO, treated surgically at our department between 2006 and 2020, were retrospectively reviewed. We compared all cases regarding demographic data, clinical presentation, imaging findings, time to diagnosis, surgical treatment, and clinical outcome in follow-up examinations. When OO occurs in the bones of the hand, it can lead to swelling and deformities, such as enlargement of the affected bone and nail hypertrophy. Initial misdiagnoses such as primary bone tumors other than OO, tendinitis, osteomyelitis, or arthritis are common. Most of the presented cases showed a prolonged time until diagnosis, whereby the primarily performed imaging modality was often not sensitive. CT proved to be the most sensitive sectional imaging modality for diagnosing OO. With adequate surgical treatment, complications and recurrence are rare.

Keywords: benign bone tumor; bone tumor; hand tumor; osteoid osteoma; tumor surgery.

Figure 1

MRI imaging of the OO in cases 1–6 (A–F) with visualization of the nidus and the surrounding edema of the bone marrow and the soft tissues. (A) Case 1: Sagittal MRI sequence showing the nidus in the proximal phalanx with a deformity of the affected bone and edema of the soft tissue. (B) Case 2: Coronal MRI sequence revealing an extensive bone marrow edema of the hamate. (C) Case 3: Coronal MRI sequence showing the juxta-articular nidus with extensive edema of the capitate, hamate, and an effusion of the intercarpal joints. (D) Case 4: Coronal MRI sequence showing the nidus in the proximal phalanx. (E) Case 5: Coronal MRI sequence revealing a juxta-articular nidus in the distal phalanx with an effusion of the distal interphalangeal joint. (F) Case 6: Sagittal MRI image showing the edema of the proximal phalanx, a central nidus with a reaction of the adjected periost as well as edema of the soft tissues.

Figure 2

CT imaging of the included cases 1–6 (A–F) of OO in the bones of the hand. (A) Case 1: Coronal CT image showing a nidus with a diameter of 9 × 6 mm and surrounding sclerosis in the proximal phalanx of the left middle finger. (B) Case 2: Axial CT image of a 6 × 4 mm nidus in the hook of the hamate. (C) Case 3: Coronal CT image revealing a juxta-articular nidus (7 × 5 mm) at the ulnar surface of the capitate. (D) Case 4: Coronal CT image showing enlargement and deformation in the proximal phalanx of the middle finger. The nidus (10 × 7 mm) is difficult to distinguish. (E) Case 5: Coronal CT Image of a 6 mm nidus in the distal phalanx in close proximity to the interphalangeal joint. (F) Case 6: Coronal CT image showing a 9 × 8 mm nidus in the proximal phalanx of the thumb with pronounced sclerosis as well as deformation and enlargement of the affected bone.

Figure 3

Intraoperative images of the surgical removal of an OO in the hook of the hamate in a 27-year-old male (case 2). (A) Approach via the Guyon’s canal. A needle is used for the position monitoring of the OO via X-ray. (B) Bony defect after curettage of the nidus and resection of sclerosis.

Figure 4

Histological findings of the resected OO from the hook of the hamate (case 2). (A) Von Kossa staining showing irregular bone trabeculae with high amounts of osteoid and fibrous stroma. The proportion of unmineralized bone mass (osteoid) is stained bright red. The mineralized bone next to the osteoid is stained black. No signs of necrosis or cellular atypia are seen. (B) In the toluidine blue staining, the osteoid appears light blue and the mineralized bone dark blue.