Splinting for Peripheral Nerve Injuries Somaya Malkawi, PhD

Radial Nerve Lesions

Ulnar nerve: Arises from the medial cord of brachial plexus (C7 to T1 roots) The nerve runs medial to the humeral artery, travels through the medial intermuscular septum, and passes superficially between the medial epicondyle of the humerus and the olecranon at the elbow joint. The ulnar nerve enters the forearm between the two heads of the flexor carpi ulnaris and descends within the anteriomedial forearm under the cover of the fl exor carpi ulnaris. In the lower third of the forearm the ulnar nerve gives off a dorsal cutaneous branch, which supplies the skin of the ulnar half of the dorsum of the hand. At the wrist the ulnar nerve sits medially to the ulnar artery and runs with this artery in the osseofibrous carpal canal called Guyon’s canal, a superficial passageway between the pisiform and hamate bones of the carpus. Just distal to the pisiform the ulnar nerve divides into two terminal branches: the superficial (palmar) cutaneous branch and the deep motor branch. The motor branch winds around the hook of the hamate and innervates the three intrinsic hypothenar muscles, the ulnar two lumbrical muscles, and the three palmar adductors and four dorsal abductors. The ulnar nerve terminates at the adductor pollicis and the deep head of the flexor pollicis brevis. The sensory branch supplies the skin of the ulnar half of the volar hand and the fifth digit and the medial half of the fourth digits

Radial Nerve Lesions (table 13-2) Check weak or lost motions for each 1. Axilla level (M+S) HIGH (wrist drop) 2. Midhumeral compression/shaft fracture (M+S) HIGH (wrist drop) 3. Forearm level- Posterior Interosseous Nerve Palsy- fracture/dislocation of elbow j (M) LOW

Radial Nerve Common Sites of Injury 4. Radial Tunnel Syndrome (btw radial head and supinator muscle (pain syndrome) 5. Superficial Radial Sensory Nerve Palsy btw ext carpi radialis longus and bachioradialis or at wrist from tight splint (S) (Wartenberg’s syndrome

High Radial Nerve Palsy Wrist drop deformity Lost wrist ext., MCP ext., and thumb radial abd and ext. Triceps spared: Elbow extension is intact (not at Axilla level) Supinator and brachioradialis are paralyzed but supination and elbow flexion is intact bcz biceps is intact

High Radial Nerve Palsy

High Radial Nerve Palsy Depending on the level of injury, triceps paresis may exist, as well as some posterior arm sensory loss along the dorsal lateral aspect of the forearm and hand

Low Radial Nerve Palsy (posterior interosseous nerve palsy Injuries to the nerve at this level can occur following compression of the nerve between the humeral and ulnar heads of the supinator muscle Radial head fracture-dislocations Tumors History of repetitive and strenuous pronation and supination.

Low Radial Nerve Palsy (posterior interosseous nerve palsy The clinical picture is: Intact radially directed wrist extension Absent MCP extension, thumb extension, and thumb radial abduction (M) Posterior interosseous nerve palsy is distinguished from high radial nerve palsy by the preservation of radial wrist extensors, brachioradialis function, and superfi cial radial nerve sensibility. Check for intact sensibility using the Semmes-Weinstein monofi laments at the fi rst dorsal web space. Assess radial wrist extension via an MMT with the forearm positioned in pronation and the elbow fl exed.

Splinting for High RNI Radial nerve motor palsy with wrist drop Custom-made dorsal forearm-based dynamic splint Promote functional hand use Base: dorsal wrist imm. S. Substitute for absent ms power By assisting MCP extensors Worn throughout the day until MMT: fair (3) If no improvement within two months, refer back to physician.

Splinting for High RNI Dynamic splint is good for a high radial nerve palsy or a posterior interosseous palsy because this splint design does not preclude use of active wrist extension and does assist with finger extension with slight wrist flexion.

Splinting for High RNI Dynamic splint not worn at night Therapist may offer static wrist imm. S. at night Therapists may offer both static and dynamic alternating between them might maximize function Watch for MCP joint contractures if the client insists on using only a static wrist splint

Splinting for post. Interos. Nerve syndrome Long arm elbow and wrist splint with elbow in flexion, forearm in neutral or slight sup., wrist in 20-30 degrees of ext. Tenodesis splint encourage wrist and finger function

Splinting for radial tunnel syndrome Long splint elbow 30 flex, forearm in full supination, wrist in slight wrist ext. (20-30) This decompress pressure on RN Worn all the time with removal for hygiene OR thumb imm. S.

Splinting for wartenberg’s neuropathy Wrist immobilization splint : wrist in 20-30 ext If pain include the thumb

Ulnar Nerve Lesion

UlnarNerve Lesions (table 13-3) Low level (wrist level) abductor digiti minimi flexor digiti minimi opponens digiti minimi fourth and third lumbrical three palmar interossei muscles and four dorsal interossei muscles deep head of the flexor pollicis brevis adductor pollicis High Level (At or above the elbow) All previously mentioned muscles Flexor Carpi Ulnaris Flexor Digitorum Profundus for digits 4, 5 Study weak and lost motions from the table

Arises from the medial cord of brachial plexus (C7 to T1 roots) The nerve runs medial to the humeral artery, travels through the medial intermuscular septum, and passes superficially between the medial epicondyle of the humerus and the olecranon at the elbow joint. The ulnar nerve enters the forearm between the two heads of the flexor carpi ulnaris and descends within the anteriomedial forearm under the cover of the fl exor carpi ulnaris. In the lower third of the forearm the ulnar nerve gives off a dorsal cutaneous branch, which supplies the skin of the ulnar half of the dorsum of the hand. At the wrist the ulnar nerve sits medially to the ulnar artery and runs with this artery in the osseofibrous carpal canal called Guyon’s canal, a superficial passageway between the pisiform and hamate bones of the carpus. Just distal to the pisiform the ulnar nerve divides into two terminal branches: the superficial (palmar) cutaneous branch and the deep motor branch. The motor branch winds around the hook of the hamate and innervates the three intrinsic hypothenar muscles, the ulnar two lumbrical muscles, and the three palmar adductors and four dorsal abductors. The ulnar nerve terminates at the adductor pollicis and the deep head of the flexor pollicis brevis. The sensory branch supplies the skin of the ulnar half of the volar hand and the fifth digit and the medial half of the fourth digits

Sensory Sensory loss, although problematic, is not as severely disabling as with the median nerve

Function Strong wrist flexion and ulnar deviation power grip via full flexion of the ulnar two digits powerful tip and lateral or key pinch powerfully to cup an object In hand manipulation The ulnar nerve allows for simultaneous strong wrist fl exion and ulnar deviation, as well as power grip via full fl exion of the ulnar two digits. This is necessary for tasks such as swinging a golf club or a hammer. Ulnar nerve integrity is also necessary to allow for powerful tip and lateral or key pinch, for the adductor pollicis and fi rst dorsal interossei assist in stabilizing the thumb and index during pinching. The hypothenar muscles and the interossei muscles allow the hand powerfully to cup an object, such as a doorknob or a basketball.

Common sites of Entrapment/Injury Cubital tunnel syndrome Guyon’s canal compression

Anteriorly: The medial epicondyle Laterally: the ulnohumeral Ligament Posteromedially: the fibrous arcade of the two heads of the flexor carpi ulnaris. Roof of this tunnel: fibrous band extending from the olecranon to the medial epicondyle of the humerus

Cupital Tunnel syndrome: description Compression of the ulnar nerve as it passes through the cubital tunnel at the elbow. Compression leads to paresthesias along the nerve course. Long withstanding compression leads to residual motor weakness Sever, prolonged ulnar nerve compression may result in the claw deformity

Cupital Tunnel syndrome: description loss of simultaneous wrist flexion and ulnar deviation Pain in the medial aspect of the elbow and tenderness over the cubital tunnel Paresthesias in the ring and little finger are present High-level lesions, such as lesions to the nerve proximal to the innervation of the flexor carpi ulnaris 25

Cupital Tunnel syndrome: description The clinical picture is one of sensory loss and motor paresis affecting the intrinsic ulnar-innervated muscles The sensory deficit involves the palmar and dorsal ulnar aspect of the hand The clinical picture is one of sensory loss and motor paresis affecting the intrinsic ulnar-innervated muscles including the interossei, and the adductor pollicis. Occasionally, the hypothenar muscles are spared The sensory deficit involves the palmar and dorsal ulnar aspect of the hand the hypothenar opponens, abductor, and flexor digiti minimi muscles are spared. The dorsal, ulnar aspect of the hand is spared because it is supplied by the more proximal dorsal cutaneous branch 26

Claw hand deformity Flattening of the normal arches of the hand Hyper-extension of MCP and flexion in PIP and DIP of 4, 5th Unable to abd and add fingers Index and middle is not affected because the lateral two lumbrical muscles, which serve to flex the metacar- pophalangeal joints, remain innervated by the median nerve.) balance between extrinsic and intrinsic muscles is lost, resulting from paresis of most of the intrinsic muscles of the hand. This results in a flattening of the normal arches of the hand. The hand will show hyper-extension of the metacarpophalangeal joints (MCP) and flexion at the distal and proximal Interphalangeal (IP) joints of the 4th and 5th digits (ring and little finger) [4]. The clawing will become most obvious when the person is asked to straighten their fingers. Patients exhibiting an ulnar claw are also very frequently unable to spread (abduct) or pull together (adduct) the fingers against resistance. This occurs because the ulnar nerve also innervates the palmar and dorsal interossei of the hand. Patients with this deficit will become increasingly easy to identify over time as the paralyzed first dorsal interosseous muscle atrophies, leaving a prominent hollowing between the thumb and forefinger. [edit] 27

Splinting for High Ulnar Nerve compression (at elbow) Elbow splint with elbow flexed 30- 45 degrees If included, wrist is positioned in neutral to 20 degrees of ext Including the wrist decreases the effects from flexor carpi ulnaris contraction The splint is worn to avoid prolonged and repetitive full flexion of the elbow (like in sleeping) which increase pressure in the cupital tunnel Extreme flexion of the elbow increases traction on the ulnar nerve

Splinting for High Ulnar Nerve compression (at elbow) Splint is worn during the night for app 3 weeks If symptoms of decreases sensibility, continuous symptoms, the client may wear the splint all the time Material: Rigid, strong enough to carry the weight of the elbow Self bonding to help formulation of the crease of elbow conformability and drapability to mold material over olecranon process

Splinting for High Ulnar Nerve compression (at elbow)

Guyon's tunnel syndrome Symptoms include a feeling of pins and needles in the ring and little fingers, and may progress to a burning pain in the wrist and hand followed by decreased sensation in the ring and little fingers and/or motor weakness

Ulnarly: pisiform and tendinous insertion of the flexor carpi ulnaris Radially: the hook of the hamate The roof of the tunnel is the flexor retinaculum After giving off the dorsal cutaneous branch about 5 to 6 cm proximal to the wrist, the ulnar nerve enters Guyon’s canal medial to the artery. Within the canal, the ulnar nerve divides into two branches: the superficial sensory branch and the deep motor branch The claw hand is worse for Guyon canal stenosis, or nerve compression at the wrist. This is an example of the ulnar paradox. Also, if the nerve is compressed at the wrist, the back of the hand will have normal sensation. 32

Guyon's tunnel syndrome cause of this syndrome is from pressure of bicycle handlebars seen with cyclists Or hard, repetitive compression against a desk surface while using a computer mouse.

Causes Most common: a ganglion, followed by occupational neuritis Other causes include a pisiform or hook of hamate fracture arthritis

Symptoms Same as the Cubital Tunnel syndrome The sensory deficit involves the palmar ulnar aspect of the hand, both sides of the little finger, and the ulnar border of the ring finger the hypothenar opponens, abductor, and flexor digiti minimi muscles are spared. The dorsal, ulnar aspect of the hand is spared because it is supplied by the more proximal dorsal cutaneous branch 35

Hand based Ulnar Nerve splint intervention Anti-claw splint Ring and little finger in 30- 45 flex Correct the claw hand posture This splint hand functional grasp Continue wear of the splint with Removal for hygiene and exercise until the muscle imbalance resolves or until tendon transfers are performed

Hand based Ulnar Nerve splint intervention Dynamic splint Figure 13-13 Finger loops with rubber bands connected to wrist band Wear throughout the day with removal for H and E

Median Nerve Lesion

Median nerve arises from the lateral and medial cords of the brachial plexus. The median nerve runs distally in the anteromedial compartment of the arm. In the cubital fossa of the anterior elbow and in the forearm, the median nerve lies medial to the brachial artery. Just distal to the elbow joint, the median nerve passes below the bicipital aponeurosis and between the two heads of the pronator teres. The median nerve gives off a purely motor branch, the anterior interosseous nerve, to the flexor pollicis longus, to the flexor digitorum profundus tendon to the index finger, and to the pronator quadratus.

Causes of Median Nerve Lesion Humeral fracture Elbow dislocation Distal radius fracture Dislocation of lunate into the carpal canal Laceration of volar wrist

Affected muscles by median nerve lesion Study Figure 13-16 and Table 13-4 Low level: abd policis brevis, flexor policis previs, opponense policis, 1st and 2nd lumbricals High level : Low level muscles and pronator teres, flexor carpi radialis, flexor policis longus, lateral half of lex digitorum, palmaris longus, flex digitorum superficialis, abd policis brevis

Functional Involvement Clumsiness with pinch Decreased power grip Power grip is affected Lumbricals of index and middle finger is weak Check sensory supply of the MN

Resulting deformity Ape hand deformity Thumb in adduction, ext. Thumb web space contract Lost opposition, Fingers show trophic changes Slight clawing of index and middle fingers bcz of loss of lumbrical innervation Result of high or low MNI

Common deficits/deformities Pronator syndrome Anterior Interosseous Nerve Palsy Carpal Tunnel Syndrome

High: Pronator Syndrome Result from strong repetitive pronation and supination as the nerve passes btw the 2 heads of pronator teres Diffuse pain in the med. forearm or distal volar arm Dysethesias in the radial three and one-half digits of the hand Symptoms may be provoked by resisted elbow flexion, often with concurrent resisted forearm pronation

High: Anterior Interosseous Nerve Palsy Entrapment neuropathy of the motor branch of the median nerve. Vague discomfort in proximal forearm Typical patient complain: difficulty with writing and cant make O with thumb and index Pain develop gradually and is followed by weakness of the muscles innervated by the branch Usually there are no sensory symptoms

Low: Carpal Tunnel Syndrome Carpal Tunnel – opening through the wrist to the hand Formed by: Bottom: Bones of wrist Top: Transverse carpal ligament

Diagnosis of CTS Most frequently a clinical diagnosis based on the patient’s reports of symptoms and clinical tests. Phalen’s Test: Patient rests elbows on table and allows wrists to drop into flexion … test is positive if client reports parasthesias within 1 minute. Tinel Test: Tapping over Carpal Tunnel produces parasthesias. EMG’s sometimes ordered to confirm (gold std.) What is the difference btw CTS and pronator syndrome – check book 295 and 296

Splinting for Pronator syndrome Avoid resisted pronation and passive supination Splint: Place elbow in 90 degrees flexion, forearm neutral, wrist in neutral to slight flex LONG ARM SPLINT If the suspected site of entrapment is at the ligament of Struthers, at the lacertus fibrosis, or at the pronator teres, fabricate a long arm splint or a sugar tong splint. Place the elbow at 90 to 100 flexion, and position the forearm in neutral rotation IMMOBILIZE WRIST IN SPLINT IF If the suspected site of entrapment is along the flexor digitorum sublimus arch

Splinting for Ant Int. Nerve compression Avoid elbow ext and extreme frearm pronation and supination Splints: Immobilize elbow 90 flex, forearm in neutral OR Small splint to block thumb IP and index DIP extension Figure 13-17

Splinting for CTS Ergonomic adaptations for home, leisure, work env Activity modifications Exercise Splint: Wrist immobilization splint that place wrist in neutral

Splinting for MNI with involved thumb As in later stage of CTS Thumb web spacer splint: for low MNI, C bar helps maintain thumb web space (LOW INJURY) Allows free wrist mobility OR Hand based thumb spica (butterfly)

Splinting for combined ulnar and median NI Splint that inhibits MP EXTENSION All digits included