Thumb CMC Arthroscopic Electrothermal Stabilization (Without Trapeziectomy)

Abstract

Instability of the thumb CMC joint is thought to lead to degenerative changes within the joint. Many treatments have been described for the already degenerative joint, but few have focused on treatment of laxity of the joint. Previously, treatment of thumb CMC laxity was limited to invasive open stabilization procedures. Recent advances in small joint arthroscopy and thermal stabilization have made it possible to treat this clinical problem in a minimally invasive fashion. Symptoms of thumb CMC joint instability include pain especially with stress. Dynamic examination with fluoroscopy can aid in the diagnosis. Initial management should consist of conservative treatment with splinting and injections, but failure of nonoperative management should lead to consideration for surgery. Electrothermal stabilization has been used with success in the hand and wrist by affecting heat labile intramolecular bonds in collagen. Standard 1R and 1U portals can be used to allow treatment of the ligaments that comprise the thumb CMC joint. Further stabilization can be provided with a pin or a “tightrope” type implant. After a period of immobilization, early motion and strengthening is started and patients are generally able to resume normal activities with reduced pain due to the increased stability of the thumb CMC joint. Whether the progression of degenerative changes is slowed or halted has yet to be fully determined, but symptomatic relief can be expected with this type of treatment.