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Long-term results of callus distraction-lengthening in the hand and upper extremity for traumatic and congenital skeletal deficiencies.

Children born with severe congenital upper-extremity limb deficiencies have been treated with many surgical techniques and use of prosthetic limbs. One surgical technique has involved the elongation of skeletal segments and their surrounding soft-tissue envelope through the process of distraction-lengthening.

### Indications for Application of Distraction-Lengthening Technique

Indications for the application of distraction-lengthening techniques include traumatic or congenital bone loss of the humerus and congenital deficiencies such as phocomelia1-4 (Fig. 1).



Fig. 1 
Radiographs showing distraction-lengthening process in a patient with right-sided phocomelia (A). A half-frame lengthening apparatus was applied laterally (B), with three sets of fixation pins in the scapula and humerus, to allow distraction-lengthening. A stable shoulder and a longer, more functional arm unit are now present (C).



In the forearm, traumatic amputation or segmental bone loss can be managed by segmental bone transport to fill a defect gap or to lengthen a short below-the-elbow segment after amputation.

The technique may be useful in the treatment of a very short forearm, as can occur in patients with radial or ulnar clubhand (Figs. 2, 3, and 4), or in the treatment of major discrepancies of radial or ulnar length, as can occur in patients with multiple hereditary exostoses.



Fig. 2 
Radiographs showing the upper limb of a young boy with ulnar agenesis and divergent forearm bones with a dislocated radial head (A). Distraction-lengthening was performed to elongate the ulnar remnant and realign the radiocapitellar joint through distraction (B and C). Photograph of the patient after the performance of muscle transfers to provide pincer grasp between the two forearm bones, similar to the result obtained with a Krukenberg procedure (D). (Fig. 2, A through D, reprinted from: Seitz WH Jr. Distraction lengthening in the hand and upper extremity. In: Green DP, Hotchkiss RN, Pederson WC, Wolfe SW, editors. Green’s operative hand surgery. 5th ed. Philadelphia: …