Items tagged “hand”

Glomangiomas, also known as glomus tumors, are benign vascular tumors typically seen at the distal extremities. On imaging, they characteristically present as small hypervascular nodules under the fingernail.  Terminology These tumors should not be confused with paragangliomas, which are somet...

In the metacarpal sign, a line drawn along the heads of the 4th and 5th metacarpals will intersect the head of the 3rd metacarpal if shortening is present. The shortened 4th metacarpal is the key to the sign. The sign is positive in up to 9.6% of normal individuals 3. It is however seen in a va...

Trigger finger is a type of stenosing tenosynovitis involving the flexor digitorum superficialis at the level of the A1 pulley. It develops due to repetitive microinjury from frequent flexion-extension movements of the fingers. Clinical presentation A patient with trigger finger finds it diffi...

Macrodystrophia lipomatosa is a rare form of localized gigantism, and many terms have been used interchangeably, with resulting confusion. They include macrodactyly, megalodactyly, digital gigantism, macromelia, partial acromegaly, macrosomia, and limited gigantism 3. It is worth noting that ma...

The extensor digitorum brevis manus (EDBM) muscle is an accessory muscle in the hand and is a normal anatomical variant.  Summary origin: distal radius and posterior radiocarpal ligament insertion: extensor hood of 2nd or 3rd digits (variable) innervation: posterior interosseous nerve actio...

Boxer knuckle (not to be confused with a Boxer fracture) refers to an appearance when there is a disruption to the sagittal bands of the extensor hood, particularly over the metacarpophalangeal (MCP) joint. Pathology It often tends to result when a clench fisted hand strikes an object in a tra...

Sesamoids, also known as sesamoid bones, are focal areas of ossification within tendons as they pass over joints 1. They can also occur in ligaments and usually measure a few millimeters in diameter. Their function is purported to be to alter the direction of the tendon and modify pressure, ther...

Mauclaire disease, also known as Dietrich disease, is a rare disease and refers to osteonecrosis of the metacarpal heads, which usually appears between ages of 13 and 18 years 1,2. This condition may lead to early closure of epiphyseal growth plate and growth disturbance of the involved finger. ...

Carpometacarpal (CMC) joint dislocations are uncommon dislocations of the hand. Epidemiology There is a strong younger male predominance. These injuries account for less than 1% of hand injuries 4 and are more common in the dominant hand. Clinical presentation Typical mechanism: punching (m...

The metacarpal bones are five long bones of the hand between the carpal bones and the proximal phalanges of the hand that make up most of the palm. Gross anatomy The metacarpal bones run from the carpus, forming the carpometacarpal joints, to the base of proximal phalanges, forming the metacar...

Ultrasound is a useful imaging modality for evaluation of the wrist, allowing high-resolution imaging of anatomy while simultaneously allowing dynamic evaluation of the joints, tendons, and ligaments. Approach There are multiple possible approaches to imaging the wrist with ultrasound. The exa...

The arterial supply to the hand is comprised of a complex vascular network formed from the branches and distal continuations of the radial and ulnar arteries. This rich vascular network can be divided into palmar and dorsal components. Palmar arterial supply The palmar arterial supply can be d...

Frostbite is a focal tissue injury from exposure to extremely low temperatures, and most commonly involves the fingers and toes. It is most commonly encountered in radiology in a differential for acro-osteolysis. Pathology Tissue injury from frostbite occurs in two ways 1: direct tissue necro...

The lumbrical muscles of the hand are intrinsic muscles of the hand associated with the flexor digitorum profundus (FDP) tendon. Summary origin: tendons of flexor digitorum profundus in the palm insertion: extensor expansion on the dorsum of proximal phalanx after passing along the lateral si...

There is only a short list of terminal tuft masses, which can arise from the adjacent soft tissues and erode the terminal tuft as well as arising from the terminal tuft itself: epidermal inclusion cyst: history of penetrating trauma tenosynovial giant cell tumor: occur laterally subungual glo...

The abductor pollicis brevis muscle is a thin subcutaneous muscle located laterally in the thenar eminence of the hand, and is one of the intrinsic muscles of the hand. Summary origin: mainly from the flexor retinaculum few fibers originate from the tubercles of scaphoid and trapezium and ten...

The opponens pollicis muscle is one of the muscles of the thenar eminence, deep to abductor pollicis brevis, and is one of the intrinsic muscles of the hand. The three muscles that constitute the thenar eminence muscle group are abductor pollicis brevis, flexor pollicis brevis and opponens polli...

The flexor digiti minimi brevis muscle of the hand lies lateral to the abductor digiti minimi, within the hypothenar eminence, and is one of the intrinsic muscles of the hand. Summary origin: hook of the hamate and flexor retinaculum insertion: proximal phalanx of 5th digit action: flexes 5t...

Tooth-knuckle injuries are sustained when the clenched fist of a patient strikes the teeth of an opponent. Terminology Tooth-knuckle injuries are also referred to as clenched fist injuries, closed fist injuries and fight bite injuries. Epidemiology These injuries are most commonly found in y...

The zone classification of flexor tendon injuries divides injuries into five zones based on anatomical location. It is the most widely used flexor tendon injury classification system (c. 2007) 1. Classification Flexor tendon injuries were classified into five zones by Kleinart and Verdan in 19...