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Hand and wrist-hand orthoses

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Hand orthoses (HOs) and wrist-hand orthoses (WHOs) are widely used in rehabilitation. They may be of a static or a dynamic (functional) design. Static orthoses immobilize, stabilize, and support a joint in a desired position. In contrast to static orthoses, dynamic orthoses permit motion to assist movement of weak muscles. HOs and WHOs are primarily prescribed for patients with central and peripheral neuropathies.


Contents

Static Orthoses: Positional Orthoses

Basic Opponens Orthosis

Of the static designs, the basic opponens orthosis is one of the simplest. It was formerly called the short opponens splint. It primarily functions to hold the thumb in a position opposing the index and middle fingers. This position is more functionally suitable. Its dorsal and palmar bars support the metacarpal arch and prevent it from flattening. The abduction bar keeps the thumb abducted and prevents thenar web contracture. The basic opponens orthosis is indicated for individuals with neuromuscular disorders resulting in muscle imbalance of the intrinsic and opponens muscle groups in the hand. Diagnoses may include spinal cord injuries at C7, C8 and T1 levels; peripheral neuropathy of ulnar and median nerves; or hemiplegia.

Components may be added to the basic opponens orthosis for increased control. Common add-ons include wrist control attachments, lumbrical bar, and finger extension assist.

Basic Opponens Orthosis Basic Opponens Orthosis. Photo courtesy of North Coast Medical, Inc., Morgan Hill, CA.


Dynamic (Functional) Orthoses

Wrist-Driven Prehension Orthosis (Tenodesis Orthosis)

This dynamic design provides functional prehension when voluntary wrist extension is available. Prehension is achieved through the "three-jaw chuck" position. The wearer grasps or takes hold of an object between digits 2 and 3 and the opposing thumb. This orthotic design utilizes voluntary wrist extension to flex the fingers at the metacarpophalangeal joint; this is known as tenodesis. The palmar and dorsal bars limit movement in the hand and fingers. The orthosis articulates at the metacarpophalangeal and wrist joints. The finger and wrist sections are connected by a cord that tightens as the wrist extends. The wearer must maintain wrist extension to maintain hold of an object. When the wearer relaxes the wrist extensors, the object is released. The tenodesis orthosis enables the wearer to achieve independence in hygeine, writing, and feeding. The orthosis is indicated for individuals with a C6 complete spinal cord injury with no finger flexion or extension. The individual must have 3+ or better wrist extension to engage wrist extension tenodesis.

Wrist-driven Prehension Orthosis Wrist-Driven Prehension Orthosis (tenodesis orthosis). I. Wrist extension: three jaw chuck II. Wrist flexion: release Photo courtesy of North Coast Medical, Inc., Morgan Hill, CA.

References




Author: Missy Malkush
Affiliation: MSPO, Georgia Tech