Metacarpal Phalangeal

Hand depth at metacarpal phalangeal joints (knuckles)... 

In pseudohypoparathyroidism, the abnormal metacarpal phalangeal line is pathognomonic, provided that other congenital abnormalities have been ruled... 

Fig. 1 Deformity of fingers resulting from deposition of xanthomatous material in joint capsules and tendons. Normal uric acid level. Tuberous and plane xanthomas overlying the dorsal aspect of the wrist and the metacarpal-phalangeal joints of fingers 2 to 5. Source Schettler 1960. Reproduced with permission of Urban and Schwarzenherg, Miinchen-Berlin, Germany...

A condylar Joint is a modified ball and socket, with partial flattening of both articular surfaces. This flattening limits the motions available as compared to a spheroid joint. An example of this is the metacarpal-phalangeal articulation. 

Craniofacial malformation are common features of FAS, which impairs the normal development of the skull, jaws, teeth, nose, eyes, and facial skin. Sometimes variable anomalies of limbs and joints are present, including congenital hip dislocations, abnormalities of the toes, and inability to extend completely the elbows or metacarpal phalangeal joints. Cardiac malformations syndrome encompasses an atrial septal defect, a patent ductus arteriosis, and cardiac murmurs representing ventricular septal defects. Anomalies of external genitalia have also been noted. 

Flexes the Metacarpal-phalangeal and carpal metacarpal joints of the thumb and assists in opposition. 

There is no information on in utero developmental effects in humans exposed to HCB, but oral exposure of young children has caused small or atrophied hands, short stature, pinched facies, osteoporosis of the carpal, metacarpal, and phalangeal bones, and painless arthritic changes. HCB has been demonstrated to cross the placenta in humans and in rodents. HCB residues have been detected in human milk and adipose tissue and in the blood of the umbilical cord of newborn infants and their mothers. Teratogenic effects were not... 

Remove right forelimb (clavicle remains with axial skeleton), and examine scapula including tuberositas delteoidea, humerus, radius, ulna, metacarpals, and phalanges from all aspects. 

In the first study, the patients had radiography of the left hand for bone age determination, and 12 had deferoxamine-induced long bone dysplasia (107). There was irregularity at the physeal-metaphyseal junction of the distal ulna (the site most frequently affected) and radius metaphyseal sclerosis was also common, especially of the ulna, but also of the radius, metacarpals, and phalanges. Radiolucent lesions occasionally accompanied metaphyseal sclerosis. In six patients with relatively mild lesions, the dysplastic changes had been missed or not mentioned. 

Relative to the phalanges the metacarpals are reasonably protected, although several series of hand fractures found the fifth metacarpal to be the most frequently injured bone (Rajesh et al. 2001 Vadivelu et al. 2006). Incidence peaks in older schoolchildren, when the mechanism of injury is usually punching, or involvement in contact sports. 

Most metacarpal shaft fractures are spiral, indicating a torsional injury (Rajesh et al. 2001). As in the phalanges, careful assessment is required of rotational deformity, although this is probably more easily performed clinically than radiologically. Treatment is similar to phalangeal injuries. If stabilisation of the metacarpal is required to maintain reduction, K-wires which pass from the fractured metacarpal across to the adjacent, intact metacarpal can be inserted. 

The hand consists of five metacarpal bones that articulate proximally with four carpal bones in the distal row. The second and third metacarpals remain relatively fixed while the first, fourth, and fifth move around this fixed segment. The five metacarpals articulate distally with the proximal phalanges of the fingers. These are usually considered ginglymus or hinge joints. They permit flexion-extension, abduction, adduction, and circumduction. 

The hand skeleton is formed by five rays made of the metacarpal bones and the phalanges and includes three hinge-type articulations that are of US interest the metacarpophalangeal joint, the proximal interphalangeal joint and the distal interphalangeal joint. 

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