Musculoskeletal Key

Imaging: The plain x-ray is usually diagnostic. Typically, OS starts intramedullary but breaches the cortex and expands in the soft tissues. It is usually a combination of radiolucency and radiodensity,…

Location: >50 % knee, then elbow, shoulder, wrist, hip, and ankle. Extra-articular form in the fingers. Clinical: Pain, limited joint motion, and sensation of joint crackling. Rare blocking and joint…

Localization: The most common locations of metastatic carcinoma are the spine, pelvis, femur, ribs, and skull. Metastases may affect any bone but are rare distal to elbow and knee. Clinical:…

Localization: About half of the cases are localized in the skeleton of the trunk and skull (particularly jaws). The other half occurs in the long bones (metaphysis or diaphysis). Not…

Location: (a) Paratendinous (frequent): in the sheath of a flexor tendon of the fingers, in the palm of the hand close to a metacarpophalangeal joint, in the wrist, on the…

Localization: The axial skeleton is the preferred site. In the appendicular skeleton, the metaepiphyses are preferred. Very rare in bones of the hand and foot. Clinical: Pain (usually relieved by…

Imaging: On x-ray – typical aspect of an osteochondroma with more abundant calcifications or ossifications, intense, and diffused radiopacities, with thicker superficial uncalcified layer and with fuzzy margins towards the…

Location: Any soft tissue site can be involved, but most common are the paravertebral region, retroperitoneum, and chest wall, followed by the extremities. Clinical: Large, destructive mass. Histopathology: Grossly it…

Location: Deep soft tissues of the thigh and buttocks. Clinical: Progressively enlarging painless mass. Imaging: X-rays, CT, and MRI reveal a large deep-seated soft tissue mass with variable mineralization. By…

Location: Among the most frequent sarcomas occurring in the hand and forearm. Palmar region of the hand, dorsal region of the forearm, plantar aspect of the foot, anterior region of…