PTP 521 Musculoskeletal Diseases and disorders

Nervous System:Peripheral Nerve Entrapments

Complex Regional Pain Syndrome

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Peripheral Nerve Dysfunctions

• Mechanisms of Injury– Transient compression– Ischemia– Crush Injury– Traction Injury – Severance of nerve

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Basic Nerve Facts

• Nerve injury– Two classification systems• Seddon

– Neuropraxia, axonotomesis, neurotmesis– Based on clinical evaluation and judgment of injury– Preoperative assessment

• Sunderland– 1st to 5th degree– Histology– Applicable after nerve exploration

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• Neuropraxia– Transient compression injury– Minimal structural changes

• Axonotmesis– Axon damaged but endoneurial tube is intact– Prognosis depends on regeneration of axon

• Neurotmesis– Entire nerve is injured (laceration)

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Neurological Dysfunctions:

A. UE Entrapment Neuropathies 1. Suprascapular Nerve2. Median Nerve3. Ulnar Nerve4. Radial Nerve

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Suprascapular Nerve Entrapment

• Suprascapular nerve emerges from trunk of the brachial plexus. Nerve roots are C5, C6 and sometimes C4

• Variable cutaneous innervation over the proximal lateral 1/3 of the arm

• Injuries can occur with:– Trauma– Overuse injuries– Mass lesion – Iatrogenic causes

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• Traumatic Causes– Scapular fractures– Clavicular fractures– Shoulder dislocations– Penetrating trauma

(gunshot wound)

• Iatrogenic Causes– Operative procedures

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• Sites of Entrapment

– Suprascapular Notch

– Spinoglenoid Notch

– Compression between the spine of the scapula and the medial tendinous edge of the infraspinatus and supraspinatus muscles

– By a mass such as a ganglion cyst, Ewings sarcoma,

• Onset: insidious unless trauma occurs

• Risk Factors: age between 20 and 50

• Symptoms: dull, aching pain in the posterior aspect of the shoulder, increases with overhead activities

• Signs: atrophy of the infraspinatus, supraspinatus muscles

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• Imaging studies:– Diagnostic Ultrasound

– MRI, T1 or T2 weighted

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Median Nerve Entrapments

1. Pronator Syndrome2. Anterior Interosseous Syndrome

3. Carpal TunnelSyndrome

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Median Nerve

a. Pronator Syndrome: nerve passes between the 2 heads of the pronator teres.

Compression occurs because of the Lacertus Fibrosis

www.aafp.org/.../20000201/691.html?print=yes

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• High median nerve injury• Insidious onset• Women 4:1• Repetitive overuse involving pronation and

supination

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Clinical Manifestations

SX: pain• Tenderness• Cramping of the proximal

anterior forearm muscles• Sensory changes on palmer

surface of digits 2,3,1/2 of 4

Signs: • Pain with resisted pronation• Tenderness to palpation of

the pronator teres• Weakness of the FPL, FDP

and Pronator Quadratus • + EMG • Weakness of pinch

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Provocation Tests

Many special tests can assist in diagnosis

Lack of sensitivity or specificity on many of the tests

1. Pronator Compression Test• Pressure applied for >30

seconds at edge of PT muscle

2. Resisted Finger Flexion, proximal PIP, 3rd digit

• Indicates compression at level of FDS

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b. Anterior Interosseous Nerve Syndrome

• Kiloh-Nevin Syndrome• Originates in the forearm at

the cubital fossa, innervates the FPL, one half of the FDP and pronator quadratus.

• Primary site of compression occurs at the point of division from the median nerve, near the tendinous insertion of the pronator teres muscle.

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Secondary areas of compression

• Accessory bicipital neurosis

• Accessory head of FPL (Gantzer muscle)

• Palmaris profundus muscle

• Flexor carpi radialis muscle

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Clinical Manifestations

• SX: 8-12 hours deep forearm pain

• does not resolve with rest

• severe pain in the forearm

• no sensory deficits

• Signs: + Pinch Test• weakness of FPL, one

half of the FDP• three jaw chuck pinch is

weak • + EMG

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Differentiation: PTS and AIS

• Sensory changesPositive: PTSNegative: AIS

• Pronator Compression TestPositive: PTSNegative: AIS

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c. Carpal Tunnel Syndrome:

• Compression of the median nerve at the wrist

• Causes: – anything that alters the space

in the carpal tunnel including: fractures, overuse, swelling of the tendons or nerve, RA, OA, diabetes, thyroid dysfunctions, pregnancy and menopause, hormonal changes,

www.mps1disease.com/patient/about/mps_pt_symp...

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Carpal Tunnel Syndrome

– Many carpal tunnel syndromes occur as a result of compensations elsewhere in the body.

– Must check C spine, shoulder and elbow for joint biomechanics.

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Clinical Manifestations

SX: • tingling and numbness in

the thumb, index and middle fingers

• aching in the thumb, wrist and digits of the hand

• burning pain at night• clumsiness and weakness of

the hand

Signs: • decreased sensation to

temperature and touch• atrophy of the thenar

muscles• Provocation tests– + phalens test – + tinels test at the wrist

• + NCS and + EMG

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RX: Carpal Tunnel Syndrome

• 60% respond to conservative treatment, splints with the wrist in 0-20dg of extension

• Avoid activities that contribute to the problem • NSAIDS • steroid injections • promote tendon gliding after the inflammation has

decreased • Surgery

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Surgical Treatment of Carpal Tunnel Syndrome

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Open Carpal Tunnel Surgery

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Open Carpal Tunnel Surgery

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Open Carpal Tunnel Surgery

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Endoscopic Carpal Tunnel Surgery

• Shorter Recovery time• Less of an incision for

healing and less scar tissue can develop

• No difference between the type of surgeries in outcomes

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Ulnar Nerve

Elbow:a.Cubital Tunnel: around the tunnel, there

are three areas that the ulnar nerve can be entrapped.

b. Cubital tunnel posterior to the medial epicondyle

c. Flexor carpi ulnaris muscle belly Wrist

a. Guyon’s canal

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Cubital Tunnel

Intermuscular septaFCU

Guyons Canal

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Cubital Tunnel Syndrome

• HX: – prolonged flexion of the elbow

– common in throwing athletes, manual laborers, and musicians.

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Clinical Manifestations

• Symptoms – pain in the proximal ulnar

aspect of the forearm – tingling in the fifth digit and

ulnar half of the fourth digit– clumsiness of the hand– hyperesthesia or numbness– muscle cramping– dull ache after activity or at

rest– radiation of pain

• Signs: – atrophy of hypothenar

eminence and of adductor muscle of thumb

– decrease in sensation within ulnar nerve distribution

– Sudomotor changes – Provocation Tests

• + Tinels at the elbow• + Fromnents signs• + elbow flexion test

– + NCS, + EMG

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Ulnar Nerve Transposition

• RX: surgery, – may transpose the nerve from the groove (anterior transposition)

– under the flexor/pronator muscle mass (submuscular transposition)

– inside the muscle (intramuscular transposition).

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Surgical Procedure

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Guyon's Canal Syndrome

• Ulnar nerve compression within the canal.

• Affects the palmar sensation and motor abilities.

• Caused by repeated or chronic trauma to the area, bone or soft tissue injury or ganglia.

• SX: decreased palmar sensation, ulnar nerve distribution

• Signs: intrinsic muscle weakness, +EMG

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Posterior InterosseousSyndrome

Superficial RadialNerve Entrapment

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Radial Nerve

Posterior interosseous Nerve: radial tunnel, compression neuropathy of the posterior interosseous nerve at the Arcade of Froshe as it enters the proximal border of the supinator muscle

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Posterior Interosseous Nerve

SX: • aching pain along the

extensor surface of the forearm and hand

• pain about the elbow

• Signs: • no sensory problems• Pain with deep

palpation distal to lateral epicondyle

• weakness of finger extensors

• Provocation Testing– + middle digit Test

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Superficial Radial Nerve Entrapment

• (Wartenberg's syndrome or Cheiralgia paresthetica)

• Cause: direct trauma to the forearm, blow to the hand, tight cast, tight watchband or bracelet

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Superficial Radial Nerve Entrapment

SX: • local tenderness at the

wrist• pain in the forearm• numbness and

parasthesia of the dorsum of the hand

Signs: • sensory loss to the

radial 2/3 of the dorsum of the hand, dorsal thumb, dorsal aspect of fingers up to ring finger (radial 1/2) from MCP to PIP level.

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Sciatic Nerve Entrapments

Piriformis Syndrome: Sciatic Nerve Entrapment.

Three specific conditions contribute to piriformis syndrome

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1. Myofascial pain referred from trigger points in the piriformis muscle

2. Nerve and vascular entrapment by the piriformis muscle at the greater sciatic foramen

3. Dysfunction of the SI joint

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SX: • Buttock pain often radiating down the posterior aspect of the

thigh and calf Signs: • Myofascial: weakness on resisted abduction with hip flexed

90 dg, tenderness to palpation decrease of hip IR ROM and pain

• Nerve: paresthesias and dysthesias in the nerve distribution, Increase in symptoms in a FABER position, SLR positive SI dysfunction: pelvic torsion noted

** may have one, two or all three co-exist

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Maeralgia Paresthetica:Uncommon disorder,

seen in obese patients, can be caused by tight underwear, above knee amputees

Prevalence: 3/10,000 cases, can occur bilaterally in 20% of population, Males > Females, more common in middle aged adults

SX: pain along the course of the nerve, pain along anterolateral aspect of the thigh, hypersensitivity, burning, tingling pain, symptoms relieved by rest

Signs: increase in pain with passive extension of the hip, decrease sensation, pain reproduced with pressure on nerve

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Tarsal Tunnel Syndrome

Most common nerve entrapment syndrome, similar to carpal tunnel in the wrist. – Entrapment of the

posterior tibial nerve or one of its branches within the tarsal tunnel.

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Clinical ManifestationsSX:• Burning dysesthesias or

anesthesias in the plantar aspect of the foot

• Pain in the plantar aspect of the foot especially at night

• Weight bearing increases the symptoms

Signs• During gait, will see a rear

foot pronation with excessive eversion of the heel during stance phase

• Or the heel will remain excessively inverted during the stance phase of gait

• Provocative Tests– + tinels at the tarsal tunnel

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Morton's NeuromaRisk factors: women between

the ages of 25 and 50, typically unilateral

SX: – electric shock or burning

sensation in the ball of the foot

– typically begin near the second toe and spread out toward the others

– intermittent pain– increases with weight bearing

and at night

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Signs: – tender to palpate – compression of metatarsal heads in unison

reproduces symptoms

RX: surgical

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Intercostal Neuralgia (Shingles)Cause: • Infection by Herpes Zoster• Mechanical Nerve

Compression by disk protrusion

• Osteophyte formation at intervertebral foramen

• Neuroma• Fracture• Postherpetic neuralgia

(nerve pain that lasts for longer than the 2-4 weeks

Incidence: 1-3 cases/1,000

Age, incidence increases to 4-12/1,000 after age 65

Prognosis: heals within 2-4 weeks

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Clinical ManifestationsSymptoms:• Headache, fever, malaise • Burning pain following the

nerve path• Unchanged by medication

or rest• Numbness or itch in a

particular placeSigns:• Rash or blisters that follow

the path of the nervewww.medhelp.org/.../Terms/2/19687.htm

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References

• Cummins CA, Messer TM, Nuber GW. Current concepts review; suprascapular nerve entrapment. J Bone Jt Surg Am. 2000; 82:415-24.

Autonomic Nervous System Dysfunction

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Complex Regional Pain Syndrome

Complex: • Varied clinical features within one

person over time• Inflammation, autonomic,

cutaneous, motor and dystrophic changes

Regional:• Most cases involve a particular

region of the body• Pain can be expressed beyond the

area of initial lesion

Pain• Essential part of diagnosis• Spontaneous pain or evoked• Allodynia or hyperalgesia

Syndrome• Signs and symptoms of CRPS are

a series of distinct correlated events

Boas, 1996; Stanton-Hicks et al., 1995

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History

• Around for 2000 years – only investigated in the last 150 years

• Doctors often did not believe patients when they described their symptoms which were out of proportion to their injury.

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Psychological versus Real Pain

• Early physicians termed this pain “nervous” pain

• Interpreted pain as a psychological problem or as a imaginary illness rather than as real pain.

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CRPS Terminology

• Neuralgia• Phantom limb pain• Causalgia• Sudek’s atrophy• Sympathetically Maintained Pain (SMP)• Reflex dystrophy• Shoulder hand syndrome

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CRPS Type ICRPS I (RSD) follows an initiating event; • Features spontaneous pain or allodynia/hyperalgesia beyond

the territory of a single peripheral nerve(s)

• Pain is disproportionate to the inciting event.

• There is or has been evidence of edema, skin blood flow abnormality, or abnormal sudomotor activity, in the region of the pain since the inciting event.

• The diagnosis is excluded by the existence of conditions that would otherwise account for the degree of pain and dysfunction.

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CRPS I

Incidence rate of 5.46 per 100,000 person-years

Prevalence of 20.57 per 100,000

Risk Factors: • Female to male ratio was 4:1 • Median age of onset at 46 years

Sandroni et al (2003):

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CPRS I Etiology

• Noxious Event

• UE > LE

• Inciting Event can include:– Minor trauma– Sprains– Bone fractures– Surgery– MI– Stroke

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CRPS

• SX: Primary symptoms are pain and swelling in the extremity, stiffness and color changes in the hand

• Signs: edema in extremity, functional deficits

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• Secondary signs and symptoms include: osteoporosis, sudomotor changes, temperature changes, trophic changes and vasomotor instability

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CRPS IICausalgia• Nerve injury has occurred,

otherwise similar to CRPS I

Symptoms:• More regionally confined• Associated with noxious

event• Spontaneous pain or

allodynia/hyperalgesia• May spread distal or

proximal to initial area

Signs:• Intermittent variable edema• Temperature changes• Motor dysfunction• Skin blood flow changes

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CRPS III

• Combination of CRPS I and CRPS II

• Has sensory and motor deficits

• Does not fit either CRPS I and II totally

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Comparison of CRPS I and CRPS II

CRPS I• Rarely have a peripheral

nerve injury• Injury is more remote from

affected extremity• Lesion of deep somatic

tissues, visceral tissues or CNS

• Myofascial Pain Syndrome may be a contributing factor

CRPS II• Neuropathic pain syndrome

• Clearly detectable peripheral nerve or plexus injury

• CRPS III: combination of the two

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Three Stages in CRPS

Acute Stage 1: 3-6 months *Identified by Bonica

SX: severe burning pain, localized to site of injury

Prognosis: good response to treatment and can recover,

Signs: • localized edema to area of

involvement• muscle spasm• difficulty initiating

movement• stiffness• limited mobility• increase in hair and nail

growth• vasomotor changes

Hendler, 2002

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2:Dystrophic Stage• Add another 3 to 6 months

(total time now 12 months)

• SX: pain is more diffuse and widespread, moves to other joints in the extremity, hair loss, brittle nails, cracked or grooved nails

• Signs: spotty osteoporosis of the bones, increase in joint thickness and muscle atrophy noted

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3: Atrophic Stage

• Greater than 12 months

• SX: intractable pain • Signs: marked trophic

changes, atrophy of muscles, weakness of joints, osteopenia of bones

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Consensus on Stages

• No Consensus as to three separate stages of CRPS

• 2002, No evidence of three separate stages in review of 113 patients with CRPS, but there was definite evidence indicating the three subtypes of CRPS

Bruehl et al, 2002