- A permanent structural deviation from the normal shape, size, or alignment, resulting in disfigurement; may be congenital or acquired. SEE ALSO: deformation (1).- Arnold-Chiari d. [MIM*207950] SYN: Arnold-Chiari malformation.- bell clapper d. a testis and epididymis free of the usual posterior attachment of the tunica vaginalis such that the tunic inserts high on the spermatic cord leaving the gonad more likely to undergo torsion.- boutonnière d. flexion of the proximal interphalangeal joint with hyperextension of the distal interphalangeal joint of the finger, caused by separation of the extensor hood and protrusion of the head of the proximal phalanx through the resulting “buttonhole”; can result from degeneration (rheumatoid arthritis) or trauma.- Erlenmeyer flask d. a d. at the distal end of the femur caused by a failure of the shaft of the bone to develop to its normal tubular shape, with the result that the bone is wide for a much longer distance up the shaft than normal; encountered in Gaucher disease. [resemblance to an E. flask]- gunstock d. a form of cubitus varus resulting from supracondylar or condylar fracture at the elbow in which the axis of the extended forearm is not continuous with that of the arm but is displaced toward midline.- J-sella d. pear-shaped or J-shaped d. of sella turcica caused by increased pressure on growing sphenoid bone; noted in the mucopolysaccharide storage diseases.- keyhole d. mucosal ectropion at the posterior edge of the anus following sphincterotomy at that location.- Madelung d. a distal radioulnar subluxation due to a relative deficiency of axial growth of the medial side of the distal radius, which, as a consequence, is abnormally inclined proximally and ulnarwards. SYN: carpus curvus.- mermaid malformation SYN: sirenomelia.- parachute d. SYN: parachute mitral valve.- reduction d. congenital absence or attenuation of one or more body parts; usually of the limbs or limb components.- silver-fork d. the d. resembling the curve of the back of a fork seen in Colles (distal radius) fracture.- swan-neck d. hyperextension of the proximal interphalangeal joint with flexion of the distal interphalangeal joint of the finger.- torsional d. in orthopedics, a d. caused by an abnormal rotation of a portion of an extremity with relationship to the long axis of the entire extremity.- whistling d. d. caused by insufficient tissue in the lower border of a repaired cleft lip, giving the appearance of whistling.
* * *1) the state of being deformed2) a physical blemish or distortion <deformities caused by thalidomide>
* * *de·form·i·ty (də-forґmĭ-te) distortion of any part or general disfigurement of the body.
Medical dictionary. 2011.