Final answer:
Soft tissue deficiencies in the thumb can be treated using various methods depending on the size and location. Treatments include using the deep posterior compartment of the forearm, flexor retinaculum and carpals, and the superficial anterior compartment of the forearm.
Step-by-step explanation:
Soft tissue deficiencies in the thumb can be treated in different ways, depending on the size and location of the deficiency. When the volar thumb deficiency is less than 2 cm, it can be treated by using the deep posterior compartment of the forearm and the metacarpophalangeal joints of the fingers to move the thumb sideways. For a volar thumb deficiency greater than 2 cm, the flexor retinaculum and nearby carpals can be used to extend the thumb. Finally, for a dorsal thumb deficiency, the superficial anterior compartment of the forearm can be targeted to bend the wrist toward the body and tilt the hand to the side away from the body.