- See:
Complex Dislocations of the MP Joint:
- Discussion:
- two types of dorsal dislocation occur in MP joint:
simple & complex;
- simple dislocations: may be reduced by closed reduction,
-
complex dislocations: usually cannot be reduced primarily;
- results from hyperextension injury;
- most often occurs in index finger (and sometine little finger);
- volar plate is torn from its proximal insertion into neck of metacarpal,
remains attached to proximal phalanx;
- in a complex dislocation, volar plate interposes into dislocated joint;
- radial collateral ligament may tear resulting in ulnar deviation of the finger;
- Radiographs:
- x-ray may show joint space widening (VP interposed);
- look for chip fractures;
- Method of Reduction:
- first hyperextended MCP joint to 90 deg, & then push base of proximal phalanx
into flexion, maintaining contact at all times w/ head of metacarpal to prevent
entrapment of volar plate in the joint;
- wrist & IP joints are flexed to relax flexor tendons,
which facilitates joint reduction;
- Treatment:
- if joint is stable following reduction, then consider buddy taping
alone, allowing immediate active motion;
A simplified technique for treating the complex dislocation of the
index metacarpophalangeal joint.
Dorsal dislocation of the MP joint of the index finger.
EB Kaplan. JBJS. 39-A. 1957. p 1081-1086.
Injury to collateral ligament of the MP joint of a finger.
M. Ischizuki.
J. Hand Surgeryl Vol 13-A. 1988. p 444-448.
Operation for collateral ligament ruptures
of the MP joints of the fingers.
JM Schubiner and DP Mass.
JBJS Vol 71-B. 1989. p 388-389.
