Orthosis for the Complete Median and Radial Nerve-injured War Casualty

Orthosis for the Complete Median and Radial Nerve-injured War Casualty MAl Timothy R. Dillingham, MD, MS SSG Frank H. Olaje, COT A Cal Praxedes V. Belandres, MD Walter Reed Army Medical Center, Physical Medicine and Rehabilitation Service, Washington, DC

MAl Mary I. Thornton-Vogel, OTR Exceptional Family Member Department, Second General Hospital, Landstuhl, Germany

rthotic fabrication and prescription for sin-

O gle nerve injuries are well described in the literature. 1- Single radial nerve injuries at or above 5

the elbow are often treated with special orthoses. Penner recommends a wrist stabilization orthosis with dynamic finger extension assists to compensate for the muscular deficits resulting from the nerve injury. Pearson,6 however, suggests that if the wrist drop from the radial nerve injury is painful, then the wrist should be splinted. If a dynamic functional orthosis is desired, then a hinged wrist with extension assist and finger extension assists is optimal. 6 Fess and Philips7 feel that all patients with complete loss of function in the radial nerve-innervated muscles should be treated with external support to position the hand. For most patients, however, a simple static wrist splint without dynamic finger extension assists is required. 6 Other authors 8 .9 suggest that an outrigger on the radial nerve orthosis with finger extension assists is the treatment of choice. Syler9 recommends that the wrist be immobilized in 30° of extension. Median nerve injuries at the wrist generally require a C-bar to maintain the first web space, compensating for lost thumb abduction, and an opponens bar providing for opposition.4,6,9,10 The optimal orthotic prescription for combined proximal median and radial nerve injuries is more complex, requiring a detailed understanding of each This paper was written as a part of Walter Reed Clinical Investigation protocol #9614. Correspondence and reprint requests to MAJ Timothy R. Dillingham, MD, Physical Medicine and Rehabilitation Service, Walter Reed Army Medical Center, Washington, DC 20307-5001. The views expressed in this article reflect those of the authors and do not represent the views of the Department of the Army or of the Department of Defense.

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This article describes an innovative dynamic modular orthosis for a Gulf War veteran who sustained complete median and radial nerve injuries at the elbow from a fragment wound. The orthosis utilized the intact ulnar nerve-innervated muscles to power a three-jaw-chuck grip. It also incorporated a hinged wrist with an elastic wrist-extension assist. A coupler mechanism functionally joined the second and third fingers and allowed thirdfinger metacarpophalangeal joint flexion to provide grasping force for both digits. A removable thumb sleeve with an elastic abduction assist stabilized the thumb interphalangeal joint, allowing the ulnar-innervated adductor pollicis to oppose during grasp. This orthosis was successfully incorporated into the patient's daily activities and was found to be utilized extensively at one-year followup. To the authors' knowledge the optimal orthosis for this situation has not been previously described. The design, fabrication, and biomechanical principles of this orthosis are presented along with a review of the literature. The authors conclude that this orthosis can improve the function of a patient with complete median and radial nerve injuries. ABSTRACT:

case's neuromuscular deficits and their functional consequences. An interesting article by Hamonet et al. l l describes a myoelectric orthosis for a patient with complete median and ulnar nerve injuries along with a partial radial nerve injury. The extensor carpi radialis longus in this case was too weak to extend the wrist; however, this muscle could myoelectrically control the orthosis. Other authors12 describe myoelectric orthoses, but prescription, fabrication, and patient training require specialized rehabilitation centers. The flexor hinge orthosis utilizing wrist extension or wrist flexion 4 to power a three-jaw-chuck grip is very useful in a variety of circumstances. 4, 13, 14 The purpose of this report is to illustrate the design, fabrication, and biomechanical principles of an orthosis that utilizes force from the ulnar nerveinnervated muscles, thus providing a functional grasp for a patient with complete median and radial nerve injuries.

CASE REPORT The patient was a 46-year-old Army Reserve sergeant who was activated during the Persian Gulf War. On 22 February 1991, he was struck by a shell fragment, which entered his left upper arm, fracturing the humerus and severing the brachial artery. He received an emergency vascular reconstruction at an evacuation hospital. At that time, he was noted to have complete median and radial nerve injuries of the left arm. Surgical clips were attached to the ends of these nerves, marking them for possible nerve grafting in the future. Pins were used tc stabilize his humeral fracture. Fifteen days after injury he arrived at Walter Reed Army Medical Center. ThE pins were replaced 22 days postsurgery with plate fix· ation of his humerus fracture. The Physical Medicine and Rehabilitation Service

wa~

consulted upon the patient's transfer to Walter Reed Army Medical Center. Initial physical examination of his left upper extremity revealed marked edema, healing surgical wounds, no evidence of infection, and only minimal tenderness elicited with palpation. His passive shoulder range of motion was limited in abduction, internal rotation, and external rotation. Elbow flexion passively was limited to 70° with a firm endpoint. Forearm pronation was full, but supination beyond 0° was absent with a firm endpoint. Passive flexion and extension of the wrist, metacarpophalangeal (MCP) flexion, and interphalangeal eIP) joint flexion were limited in all fingers of the left hand (Table 1). Strength initially was good in the proximal shoulder muscles, trace to poor in elbow flexion and in elbow extension, and zero in forearm supination and pronation. Wrist flexion strength was fair with ulnar deviation of the wrist. Wrist extension and MCP joint extension in all fingers were zero. Left thumb abduction, extension, opposition, and IP joint flexion were zero. First dorsal interosseus muscle testing revealed poor strength. Thumb adduction was good. Distal interphalangeal (DIP) joint flexion was zero in the second finger, trace in the third finger, and good in the fourth and fifth fingers. Sensation testing to pinprick revealed absent sensation over the palmar and dorsal TABLE 1.

Passive Range of Motion in the Left Arm*

Initial 75 30 25 135

Discharge 115 40 30 165

One-year Follow-up 180 45 55

Flexion Extension Pronation Supination

70 25 90 0

75 14 90 10

70 20 90 0

Wrist

Flexion Extension

35 35

60 30

45 35

Thumb

Mep IP Palmar ABO

0/60 0160

0/65 0/60

10/50 0/30

Index finger

Mep PIP DIP

0170 0/95 0/55

0/94 0/90 0/60

0/65 0/80 0/60

Middle finger

Mep PIP DIP

0/60 0/95 0/65

0/90 01105 0170

0/60 0/90 0/65

Ring finger

Mep PIP DIP

0/100

0/50

0/84

0/60

0/80

0/55 01105 0/65

Mep PIP DIP

0/35 0/95 0/65

0/65

Joint Shoulder

Action ABO IR ER Flexion

Elbow

Small finger

55

01115

01110

0/95

40

aspects of the thumb, and the second and third fingers. Mild sensory loss was noted in the medial antebrachium. The deep tendon reflexes in the left arm were absent. The left radial pulse was intact. Examination of the other extremities was unremarkable. Electrodiagnostic testing one month postinjury revealed findings consistent with complete median and radial nerve injuries at the elbow along with a partial (axonal loss) left ulnar nerve injury. There was also a mild brachial plexopathy with spontaneous activity in the deltoid and teres minor muscles but with full recruitment. In addition, there was marked soft-tissue injury in the brachial region involving the biceps and triceps, which complicated electrodiagnostic interpretation. Plain radiographs of the left elbow and humerus obtained at Walter Reed revealed exuberant bony callous formation with heterotopic ossification and a stable, healing fracture. The patient's rehabilitation program initially consisted of compression with elastic wrapping, elevation, and intermittent pneumatic compression mobilizing the arm edema, and resulting in marked improvement and subsequent edema control. Improving and maintaining adequate functional range of motion in the patient's left hand and arm required extensive therapy, including prolonged stretching by occupational therapists and a self-program, which the patient diligently followed. The humerus fracture stabilization was strong enough to allow careful active assistive range of motion of the elbow. A static dorsal orthosis was fabricated from Polyform (Smith & Nephew Rolyan, Menomonee Falls, WI) and designed to provide an alternating MCP extension force and finger flexion force. The patient alternated the flexion and extension every few hours to provide prolonged stretch to the MCP and IP finger joints (Figs. 1 and 2). His range of motion in the wrist and hand improved enough to allow a functional dynamic orthosis to be fabricated (Table 1). Elbow range of motion in flexion remained limited to about 70° and supination to 0°. Functional shoulder range of motion was achieved. Muscles not completely denervated, the ulnar-innervated muscles, the triceps, the biceps, and the proximal arm and shoulder muscles, were exercised with active assistive, then active resistive exercises. The ulnar-in-

0/40 0/103 0/90

*When two numbers are given with a I, the first is the angle of maximal extension, and the second is the angle achieved with flexion. The grading scheme for range of motion uses the anatomic position as the baseline, or zero starting position, with full extension at zero. Abbreviations are: Mep = metacarpophalangeal joint, PIP = proximal interphalangeal joint, DIP = distal interphalangeal joint, IP = interphalangeal joint, ABO = abduction, IR = internal rotation, and ER = external rotation. Initial measurements were made during the first 2 months following admission and discharge measurements were obtained approximately 6 months postinjury.

FlCURE 1. Palmar view of the static orthosis used initially for promoting increased range of motion. The elastic assists were used to provide prolonged static flexion to the fingers.

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FIGURE 2. Dorsal view of the static orthosis showing the metacarpophalangeal joint elastic extension assists.

nervated muscles (interossei) improved markedly in strength, achieving a level of good. Upon discharge, good strength in wrist flexion and good DIP joint flexion of the third, fourth, and fifth fingers had been attained. Elbow flexion and extension strength had improved to a level of good. Active pronation and supination remained zero. Metacarpophalangeal joint flexion strength in the second through the fifth fingers became good. The proximal shoulder muscle (deltoid) strength became normal. The improvement in the joint ranges of motion of the left upper extremity are shown in Table 1. Different therapists and physicians obtained the measurements shown in Table 1, hence interrater differences can be expected. 15 A dynamic orthosis (Fig. 3) was fabricated to allow the MCP and DIP flexion of the third finger to power a three-jaw-chuck grasp. This was accomplished by means of a dorsal Polyform orthosis (a and b in Fig. 3) to which other components were attached. A coupler device (c in Fig. 3; Fig. 4) functionally joined the second and third fingers. This coupler was fabricated from %2-in coppercoated steel wire (c in Fig. 4), attached to thermoplastic [Orfit 1/16-in Microperf (Luxilon Industries Co., PUBA,

Antwerp, Belgium)] pieces that fit around the third finger (b in Fig. 4), and a dorsal cap with a Velcro closure around the second finger (a in Fig. 4). A proximal rigid cross-piece (d in Fig. 4) with a Velcro closure enclosed both the second and the third fingers. A small hook on the coupler (e in Fig. 4) was attached to an elastic extension assist (f in Fig. 3), providing second and third finger extension. To stabilize the thumb, a removable sleeve was made from thermoplastic (Polyform l/8-in plain), which fit over the thumb (d in Fig. 3). It was attached to the orthosis by an elastic band providing an abducting and opposing force (g in Fig. 3) and placing the thumb in opposition. A volar polyform plate (h in Fig. 3) provided the base to which the elastic thumb abduction assist was attached. This allowed the adductor pollicis muscle to adduct the thumb during grasp. Extension assists were incorporated, providing dynamic MCP extension for the fourth and fifth fingers and for the coupler (f in Fig. 3). The extension assists were composed of elastic bands with nylon cords that passed through eyelets in the orthosis. They were anchored to the orthosis with Velcro. Hinges at the wrist (i in Fig. 3) allowed active wrist flexion from the flexor carpi ulnaris muscle and extension from an elastic assist (e in Fig. 3). The patient's ability to flex his wrist improved his function, particularly when using the three-jaw-chuck grip (Fig. 5) for grasping objects on a desk. The orthosis (Fig. 6) was equipped with various useful items, including a watch. Extensive patient education and training were required to optimize this patient's hand function with the orthosis. Proper routine skin inspection to evaluate insensate skin for breakdown was taught, along with a daily self-program of range of motion and strengthening. At one-year follow-up, the patient was using the orthosis daily for 12 hours without discomfort or skin breakdown. The joint ranges of motion at one-year followup revealed that many of the gains made in passive range of motion had been lost (Table 1), yet his use of the orthosis was extensive. The exception to this was the shoulder range of motion, which continued to improve. The patient's work entailed primarily desk activities during which the left hand was used for reaching and grasping small objects, then stabilizing them while

FIGURE 3. Dorsal (left) and palmar (right) views of the dynamic orthosis. See the text for details of the componentry.

\

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\

\

DISCUSSION

The coupler device. See the text for details of the componentry. FIGURE 4.

FIGURE 5.

thosis.

A three-jaw-chuck grip using the dynamic or-

FIGURE 6.

Profile view of the orthosis.

using his right (dominant) hand. The intact ulnar sensation in the fourth and fifth fingers allowed him to locate items prior to grasping them. When running, he used a static wrist orthosis to prevent excessive wrist flexion and extension. He was able to grasp briefcases and books with his fourth and fifth fingers using a hook grasp.

In median nerve injuries at the wrist, the commonly prescribed orthotic components include a Cbar to abduct the thumb and an opponens bar to stabilize the first carpometacarpal joint in an opposed position suitable for three-jaw-chuck grasp.4.6 This rigidly fixed thumb can interfere with dressing. Watanabe et al. 3 described an orthotic device using a spring wire attached to a wrist cuff that abducts and opposes the thumb, yet presents a low profile and minimally interferes with dressing. Long4 also described a spring swivel thumb operating in a similar fashion. Radial nerve injuries result in weakened wrist extensor and finger extensor muscles. Orthotics for this type of injury typically stabilize the wrist6 •7 •9 and sometimes incorporate mechanisms for elastic MCP extension assistance. 2 ,4,8 A hinged wrist joint with elastic wrist extension assist can also be included. S.6 The multiplicity of nerve injuries in this patient necessitated an orthosis that compensated for the specific neuromuscular deficits. A coupler device utilized third finger flexion to power a three-jaw-chuck grasp. The utilization of the long finger flexors of digits 4 and 5 to power a flexor-hinge hand orthosis has been described by Long,4 who referred to a "flexor bar" extending ulnarward under the DIP joints of the fourth and fifth fingers. This flexor bar, attached to the flexor hinge part of the orthosis, provided the force for grasp. The fourth and fifth fingers were kept from "dangling" into the palmar area by this bar, as described by Long. 4 The coupler device for this Gulf War casualty, however, utilized MCP flexion of the third finger to power the grasp. This flexion force was derived from the interosseus muscles and from the flexor digitorum profundus (FOP) muscle to the third finger. The improved DIP flexion of the third finger may have resulted from reinnervation of the median nerve-innervated FOP by a branch of the intact ulnar nerve to the ulnar-innervated FOP muscles. Independent movement of the fourth and fifth fingers allowed a strong functional hook grasp for carrying briefcases and books. The proximal median nerve injury that this patient sustained denervated the flexor pollicis longus. This necessitated thumb IP joint stabilization. The thumb sleeve described in this report stabilized both the IP joint and the MCP joint. An elastic band abducted and opposed the thumb, allowing the ulnar-innervated adductor pollicis muscle to stabilize the thumb during grasp. A volar plate (h in Fig. 3) provided a firm base for attachment of the thumb elastic assist (g in Fig. 3). An elastic wrist extension assist and hinge joints at the wrist allowed this patient to use active wrist flexion, increasing his function. Bender,S and Pearson6 describe incorporation of this useful principle into orthotics for radial nerve injuries. In this casualty's case, the wrist flexion power originated primarily from the intact flexor carpi ulnaris. The hinge joints at the wrist prevented ulnar deviation during wrist flexion. Metacarpophalangeal joint extension assists October-December 1992

215

for radial nerve injuries, described in the literature/,4-6,8 were also incorporated into this orthosis, The severity of the injuries sustained by this patient precluded consideration of tendon transfers, A typical tendon transfer described for a radial nerve injury involves using median-innervated forearm muscles to power the radial extensor muscles,16 This, however, was not possible, because the median nerve injury occurred proximal to the innervation of the forearm muscles. Edema control is the beginning of an effective hand-injury rehabilitation program. 17 - 19 The initially marked edema in this casualty was likely due to a combination of immobilization, lymphatic disruption, soft-tissue injury, and reduced muscle activity secondary to the nerve injuries. To control this edema, active motion, elevation, elastic compression, and intermittent pneumatic compression were used. 18 ,19 Recurrent, prolonged, and fluctuating edema can impede the ability to wear an orthotic device. Fortunately, this patient's edema was controlled. For any orthosis to be effective, there must be a functional range of motion. A static dorsal orthosis with elastic assists was used initially to improve finger range of motion by alternating the elastic extensor and flexor forces frequently during the day to allow several hours of prolonged passive stretch in each direction. This resulted in development of a functional passive range of motion in all jOints of the hand. Although normal range of motion was not achieved, enough was obtained to allow operation of the dynamic orthosis. Forearm supination along with elbow flexion continued to be limited with a firm endpoint. This was likely due to the heterotopic bone and exuberant callous formation at the elbow noticed on plain x-ray. The rehabilitation program for this war casualty utilized active assistive and active resistive exercises to improve the strength of the proximal arm muscles and ulnar-innervated muscles. The electro diagnostic information was helpful in revealing the partial ulnar nerve injury and the brachial plexus involvement. Based on this information, an exercise program was established for strengthening muscles that were not completely denervated. To transfer power, there must be a muscle grade of good, 4 and this was achieved in the ulnar-innervated muscles. Strengthening the proximal shoulder muscles and the elbow flexors and extensors was emphasized. Improved strength in these muscles markedly increased the function of the injured arm. The absence of any active supination within the patient's passive range of motion was probably due to functional loss ofthe biceps muscle insertion into the radial tuberosity due to the trauma, in addition to the complete radial nerve injury. Loss of active pronation was due to the proximal complete median nerve injury. A low-profile dorsal orthotic device reduced interference with palmar sensation. Sensory reeducation is very important in cases such as this.16,2o,21 The unrestricted motion of the fourth and fifth fingers provided valuable sensory feedback that was utilized in fine grasping activities. Extensive training helped utilize this valuable intact palmar sensation. 216

JOURNAL OF HAND THERAPY

For an orthotic brace to be used, it must provide the ability to complete a desirable activity. 4, 16 This patient used the orthosis during work and avocational pursuits, including carpentry. At one-year follow-up, the orthosis continued to be utilized throughout the day. Education regarding the orthosis,8,17,22,23 along with extensive training by the rehabilitation team, no doubt contributed to this wounded soldier's full acceptance of the orthotic device, and its incorporation into his daily activities.

COMMENT The prescription and fabrication of an orthosis for a war-injured soldier with complete median and radial nerve injuries were presented. The adaptations incorporated into the orthosis included a coupler device, allowing the third finger to power a functional grasp, and a modular sleeve with an elastic abduction assist stabilizing the thumb. We conclude that this orthotic device can improve the function of a patient with complete median and radial nerve injuries. Acknowledgments The authors gratefully acknowledge the contributions of SGI Troy A. Bourgeau, COTA (Walter Reed Army Medical Center), for his contributions towards the orthotic design, and the superb illustrations provided by Bill Discher (scientific illustrator at the Armed Forces Institute of Pathology, Walter Reed Army Medical Center, Washington, DC).

REFERENCES 1. Delisa JA, Greenberg S: Basic upper extremity orthotics. Am J Family Pract 24(2):169-175, 1981. 2. Penner DA: Dorsal splint for radial palsy. Am J Occup Ther 26(1):46-47, 1972. 3. Watanabe H, Ogate K, Okabe T, Amano T: Hand orthosis for various finger impairments-The K U finger splint. Prosthet Orthot Int 2:95-100, 1978. 4. Long C: Upper limb orthotics. In Redford JB (ed): Orthotics Etcetera, Second Edition. Baltimore, Williams and Wilkins, 1980, pp. 190-282. 5. Bender LF: Upper extremity orthotics. In Kottke FJ, Lehmann JF (eds): Krusen's Handbook of Physical Medicine and Rehabilitation, 4th Edition. Philadelphia, W. B. Saunders, 1990. 6. Pearson SO: Splinting of the Nerve Injured Hand. In Hunter JM, Schneider LH, Mackin EJ, Callahan AD (eds): Rehabilitation of the Hand, Second Edition. St. Louis, C. V. Mosby, 1984. 7. Fess EE, Philips CA: Hand Splinting: Principles and methods, Second Edition. St. Louis, C. V. Mosby, 1978. 8. Schutt AH: Upper extremity and hand orthotics. Phys Med Rehabil Clin North Am 3(1):223-241, 1992. 9. Syler MM: Hand rehabilitation. In Hopkins HL, Smith HD (eds): Willard and Spakman's: Occupational Therapy, Seventh Edition. Philadelphia, J. B. Lippincott, 1988. 10. Solie GA: Short opponens hand orthosis. Am J Occup Ther 32(9):588, 1978. 11. Hamonet C, Boulongne D, Simon S, Bedhet P: A myoelectriccontrolled orthosis. Hand 7(1):63-66, 1975. 12. Silverstein F, French J, Siebens A: A myoelectric hand splint. Am J Occup Ther 28(2):99-101, 1974. 13. Stenehjem J, Swenson J, Sprague C: Wrist driven flexor hinge

14. 15.

16. 17. 18.

orthosis: Linkage design improvements. Arch Phys Med Rehabil 64(11):566-568, 1983. Shepherd Cc, Ruzicka SH: Tenodesis brace use by persons with spinal cord injuries. Am J Occup Ther 45(1):81-83, 1991. Cole TM, Tobis JS: Measurement of musculoskeletal function. In Kottke FI, Lehmann JF (eds): Krusen's Handbook of Physical Medicine and Rehabilitation, 4th Edition. Philadelphia, w. B. Saunders, pp. 580-592. Barton NJ: Radial nerve lesions. The Hand 5(3):200-208, 1973. Parker BC: Rehabilitative aspects of nerve injuries of the hand. Orthop Nurs 7(1):29-34, 1988. Colditz JC: Dynamic splinting of the stiff hand. In Hunter JM, Schneider LH, Mackin EI, Callahan AD (eds): Rehabilitation

of the Hand, St. Louis, C. V. Mosby, 1984. 19. Hunter JM, Mackin EJ: Edema and bandaging. In Hunter JM, Schneider LH, Mackin EI, Callahan AD (eds): Rehabilitation of the Hand, Second Edition. St. Louis, C. V. Mosby, 1984. 20. Dellon AL, Curtis RM, Edgerton MT: Reeducation of sensation in the hand after nerve injury and repair. Plast Reconstr Surg 53(3):297-305, 1974. 21. Fess EE: Rehabilitation of the patient with peripheral nerve injury. Hand Clin 2(1):207-215, 1986. 22. Rizzo F, Hamilton BB, Keagy RD: Orthosis research evaluation framework. Arch Phys Med Rehabil 56(7):304-308, 1975. 23. McDougall D: Modem concepts in hand orthotics. Hand 7(1):5862, 1975.

SURGERY AND REHABILITATION OF THE HAND· '93 SYMPOSIUM AND WORKSHOP Sponsored by Hand Rehabilitation Foundation and Jefferson Medical College of Thomas Jefferson University

Honored Senior Professors

PAUL W. BROWN, M.D. Bridgeport, Connecticut

JUDIm A. BELL-KROTOSKI, OTR, FAOTA, CHT Carville, wuisiana

March 13 - 16, 1993, Philadelphia, Pennsylvania Course Chairmen James M. Hunter, M.D. Lawrence H. Schneider, M.D. Evelyn J. Mackin, P.T. Workshop Coordinator Anne D. Callahan, MS, OTR/L, CHT Anatomy Laboratory Workshops: Shoulder and Hand Closed Circuit TV - Live Surgery: Active Tendon Implant Reconstruction A symposium and workshop designed to present to the surgeon, resident, physiatrist, physical and occupational therapist and registered nurse a unique opportunity to correlate the concepts, indications, surgical techniques, and pre- and post-operative care of the injured and disabled upper extremity. "Hands on" workshops and panel discussions will complement the didactic sessions. Information: Evelyn J. Mackin, PT, Hand Rehabilitation Foundation, 901 Walnut St. Philadelphia PA 19107 (215925-4579)

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