Parsonage-Turner syndrome is also known as acute brachial neuropathy and acute brachial radiculitis.Other names used are Parsonage-Aldren-Turner syndrome, neuralgic amyotrophy, brachial neuritis, or brachial plexitis. The syndrome refers to a rare set of symptoms resulting from inflammation of unknown etiology of the brachial plexus.
Erb's palsy (Erb-Duchenne Palsy) is a paralysis of the arm caused by injury to the upper group of the arm's main nerves, specifically the upper trunk C5-C6 is severed. These form part of the brachial plexus, comprising the ventral rami of spinal nerves C5-C8, and T1.These injuries arise most commonly, but not exclusively, from shoulder dystocia during a difficult birth.Depending on the nature of the damage, the paralysis can either resolve on its own over a period of months, necessitate rehabilitative therapy, or require surgery.Klumpke's paralysis (or Klumpke's palsy or Dejerine-Klumpke palsy) is a variety of partial palsy of the lower roots of the brachial plexus.The brachial plexus is a network of spinal nerves that originates in the back of the neck, extends through the axilla (armpit), and gives rise to nerves to the upper limb. Klumpke's paralysis is a form of paralysis involving the muscles of the forearm and hand, resulting from a brachial plexus injury in which the eighth cervical (C8) and first thoracic (T1) nerves are injured "either before or after they have joined to form the lower trunk. The subsequent paralysis affects, principally, the intrinsic muscles of the hand and the flexors of the wrist and fingers". Forearm pronators and wrist flexors may be involved, as may dilators of the iris and elevators of the eyelid (both of which may be seen in the case of associated Horner's Syndrome). The classic presentation of Klumpke's palsy is the “claw hand” where the forearm is supinated and the wrist and fingers are hyperextended. If Horner syndrome is present, there is miosis (constriction of the pupils) in the affected eye.
Plexopathy is a disorder affecting a network ofnerves, blood vessels, or lymph vessels.The region of nerves it affects are at the brachialor lumbosacral plexus.Symptoms include pain, loss of motorcontrol, and sensory deficits.
There are two main types of plexopathy; Brachial plexopathy andLumbosacral Plexopathy. They are usually caused from some sort oflocalized trauma such as a dislocated shoulder. The disorder can alsobe caused secondary to a compression, co-morbid vascular disease,infection, or may be idiopathic with an unknown cause.
The brachial plexus is anetwork of nerves thatconducts signals from thespinal cord, which ishoused in the spinal canalof the vertebral column (orspine), to the shoulder, armand hand. These nerves originate inthe fifth, sixth, seventh andeighth cervical (C5-C8), and Diagram illustrates basic anatomy offirst thoracic (T1) spinal brachial plexus. Brachial plexus isnerves, and innervate the formed by anterior rami of C5-T1 nervemuscles and skin of the roots. Roots are located in neural foramina and trunks between scalenechest, shoulder, arm and muscles. Divisions are posterior tohand. clavicle, and cords are inferior to it. LC Brachial plexus injuries, or = lateral cord, PC = posterior cord, MClesions, are caused by = middle cord.damage to those nerves.
Brachial plexus injuries, or lesions, can occur as a result ofshoulder trauma, tumours, or inflammation. The rareParsonage-Turner Syndrome causes brachial plexusinflammation without obvious injury, but with neverthelessdisabling symptoms. But in general, brachial plexus lesionscan be classified as: i) Obstetric injuries may occur from mechanical injury involving shoulderdystocia during difficult childbirth.The babys shoulders may become impacted during the birth processcausing the brachial plexus nerves to stretch or tear.The excessive stretch results in incomplete sensory and/or motor functionof the injured nerve.ii) Traumatic injury may arise from several causes.(Sports, high-velocity motor vehicle accidents, falls from a height on to theside of the head and shoulder, whereby the nerves of the plexus areviolently stretched, injury from a direct blow to the lateral side of thescapula, direct violence or gunshot wounds, by violent traction on the arm,or by efforts at reducing a dislocation of the shoulder joint“)
CausesIn most cases the nerve roots are stretched or tornfrom their origin, since the meningeal coverings ofthe nerve roots are thinner than the sheaths enclosingthe peripheral nerves. The epineurium of theperipheral nerve is contiguous with the duramater, providing extra support to the peripheralnerves.Brachial plexus lesions typically result from•excessive stretching;•rupture injury where the nerve is torn but not at thespinal cord;•avulsion injuries, where the nerve is torn from itsattachment at the spinal cord.•build-up of scar tissue around a brachial plexusinjury site (put pressure on the injurednerve, disrupting innervation of the muscles)
Brachial plexus lesions can be divided into two types:1) An upper brachial plexus lesion, which occurs from excessive lateral neck flexion away from the shoulder. Most commonly, falling on the neck at an angle causes upper plexus lesions leading to Erbs palsy. This type of injury produces a very characteristic sign called Waiters tip deformity due to loss of the lateral rotators of the shoulder, arm flexors, and hand extensor muscles.2) Much less frequently, sudden upward pulling on an abducted arm (as when someone breaks a fall by grasping a tree branch) produces a lower brachial plexus lesion, in which the eighth cervical (C8) and first thoracic (T1) nerves are injured "either before or after they have joined to form the lower trunk. The subsequent paralysis affects, principally, the intrinsic muscles of the hand and the flexors of the wrist and fingers". This results in a form of paralysis known as Klumpkes paralysis.
Injury ClassificationThe severity of brachial plexus injury is determined by the type ofnerve damage.There are several different classification systemsfor grading the severity of peripheral nerve and brachial plexusinjuries. Most systems attempt to correlate the degree of injurywith symptoms, pathology and prognosis.A more recent and commonly used system described by the lateSir Sydney Sunderland, divides nerve injuries into five degrees:•first degree or neurapraxia, following on from Seddon, in whichthe insulation around the nerve called myelin is damaged but thenerve itself is spared,•second through fifth degree, which denotes increasing severityof injury•fifth degree injuries, the nerve is completely divided
Seddons classification (based on three main types of nerve fiberinjury, and whether there is continuity of the nerve)1) Neurapraxia: The mildest form of nerve injury. It involves an interruption of the nerve conduction without loss of continuity of the axon. Recovery takes place without wallerian degeneration.2) Axonotmesis: Involves axonal degeneration, with loss of the relative continuity of the axon and its covering of myelin, but preservation of the connective tissue framework of the nerve (the encapsulating tissue, the epineurium and perineurium, are preserved).3) Neurotmesis: The most severe form of nerve injury, in which the nerve is completely disrupted by contusion, traction or laceration. Not only the axon, but the encapsulating connective tissue lose their continuity. The most extreme degree of neurotmesis is transsection, although most neurotmetic injuries do not produce gross loss of continuity of the nerve but rather, internal disruption of the nerve architecture sufficient to involve perineurium and endoneurium as well as axons and their covering. It requires surgery, with unpredictable recovery.
Presentation (Signs and Symptoms)Signs and Symptoms may include a limp or paralyzed arm, lack ofmuscle control in the arm, hand, or wrist, and lack of feeling or sensationin the arm or hand. Although several mechanisms account for brachialplexus injuries, the most common is nerve compression or stretch. Themost severe form of injury is nerve root avulsion, which results incomplete weakness in corresponding muscles. This usually accompanieshigh-velocity impacts that occurs during motor vehicle or bicycleaccidents.The cardinal signs of brachial plexus injury then, are weakness in the arm,diminished reflexes, and corresponding sensory deficits.Erbs palsy. "The position of the limb, under such conditions, is characteristic: thearm hangs by the side and is rotated medially; the forearm is extended andpronated. The arm cannot be raised from the side; all power of flexion of the elbowis lost, as is also supination of the forearm".In Klumpkes paralysis, a form of paralysis involving the muscles of the forearmand hand, a characteristic sign is the clawed hand, due to loss of function of theulnar nerve and the intrinsic muscles of the hand it supplies.
DiagnosisThe diagnosis may beconfirmed by an EMGexamination in 5 to 7days. The evidence ofdenervation will beevident. If there is nonerve conduction 72hours after theinjury, then avulsion ismost likely.
TreatmentTreatment for brachial plexus injuries includes occupational orphysical therapy and, in some cases, surgery. Some brachialplexus injuries may heal without treatment.Many infants improve or recover within 6 months, but those thatdo not have a very poor outlook and will need further surgery totry to compensate for the nerve deficits. The ability to bend theelbow (biceps function) by the third month of life is considered anindicator of probable recovery, with additional upwardmovement of the wrist, as well as straightening of thumb andfingers an even stronger indicator of excellent spontaneousimprovement.Gentle range of motion exercises performed byparents, accompanied by repeated examinations by aphysician, may be all that is necessary for patients with strongindicators of recovery.
PrognosisThe site and type of brachial plexus injurydetermine the prognosis. Avulsion and ruptureinjuries require timely surgical intervention for anychance of recovery. For milder injuries involvingbuild-up of scar tissue and for neurapraxia, thepotential for improvement varies, but there is a fairprognosis for spontaneous recovery, with a 90 -100% return of function.
The anterior divisions of the lumbar nerve, sacral nerve, andcoccygeal nerves form the lumbosacral plexus, the firstlumbar nerve being frequently joined by a branch from thetwelfth thoracic.For descriptive purposes this plexus is usually divided intothree parts:1. lumbar plexus2. sacral plexus3. pudendal plexus
The lumbosacral plexus issituated within the relativeprotection of the axialskeleton, making blunt traumaa relatively uncommon causeof injury. The most commoncauses of a lumbosacralplexopathy are usually bydirect compression, diabeticneuropathy, complications ofpelvic surgery, or parturition.Separating a plexopathy fromother neurological effects ofother spinal-related problemsis often a diagnostic challenge.
Diabetic plexopathyDiabetic plexopathy typically affects the lumbosacral plexus more than abrachial. It is distinguished from a peripheral polyneuropathy of long-standing diabetes by its predominantly proximal symptoms. The majorityof patients are in their sixth and seventh decade and also have documenteddistal peripheral polyneuropathy. Most frequent clinical presentation of adiabetic lumbosacral plexopathy is anterior thigh pain, with secondaryproximal leg muscle weakness. The muscle weakness is most pronouncedin the quadriceps muscles. Sensory loss is generally less pronounced,although patellar reflexes typically are absent or sluggish. Withprogression, noticeable muscle wasting occurs, resulting in significantatrophy and weight loss. There is a trend for progression from unilateral tobilateral lower-extremity involvement.Diagnosis is therefore based on presentation, presence of diabetes, and thepresence of acute electrodiagnostic findings to be discussed later.Therapy is ultimately focused on the control of the hyperglycemia. Mostpatients who achieve glucose control typically have significant, butincomplete, recovery of muscle strength. Maximal improvement canrequire more than one year. After control of the hyperglycemia,rehabilitation strategies address pain management, maintenance of range ofmotion, and compensatory mechanisms for knee extensor weakness.
Traumatic PlexopathyTraumatic plexopathy of the lumbosacral plexus typically must besufficient to produce an unstable, vertical fracture of the pelvicregion since the plexus is other-vise well protected from directimpact. Fractures to the sacroiliac joint usually involve theintralateral lumbosacral trunk with impairment clinically seen at theL5 and S1 levels. Fractures or dislocations of the hip joint canproduce traction injuries to the lumbosacral plexus. Treatment:Surgical intervention is imminent and requires initial periods ofimmobilization post-operatively. The initial lesions can slowlyrecover during the post-operative rehabilitation.Prognosis: Poor recovery
Hemorrhagic PlexopathyHemorrhagic plexopathy is usually caused in the retroperitonealregion, which can compress on the plexus as it passes through either theiliac or psoas muscles. An expanding hematoma within the morelaterally located iliopsoas muscle can cause local compression of thefemoral nerve at the point along its course from its origin to the inguinalligament. Clinical presentation:1) Compression (Diffuse) in psoas muscle Weakness: Obturator & femoral nerve territory Pain: Mild or none Mass: None palpable2) Compression of femoral nerve in iliacus muscle Pain: In groin or iliac fossa Radiates to anteromedial thigh & medial lower leg Weakness: Quadriceps Sensory: Reduced in anteromedial thigh & saphenous distribution Reflex loss: Knee Mass: May be palpable in groin
Radiation-Induced Lumbosacral PlexopathyRadiation-induced lumbosacral plexopathy is similar to that affecting thebrachial plexus. Onset is difficult to determine, occurring from one to 31years after radiation. Patients receiving an external beam or internal cavityradiation are equally susceptible. Patients generally present with slowlyprogressive, bilateral lower extremity weakness that tends to affect the distalmuscles more. Paresthesia and numbness are less frequently reported in theinitial symptoms. Symptom progression can eventually stabilize. Patients areusually severely disabled by that time. Therefore, early diagnosis or properfollow up by the oncologist/family physician is essential.Weakness: Distal legsLatency: Months to yearsProgression: SlowPain: Late; Not disablingCancer type: Gynecological; TesticularPredisposing treatment : High radiation dose: > 55 Gy Chemotherapy NOT hormonalElectrodiagnostic : EMG: Myokymia NCV: Absent late reflexesImaging: Multifocal fibrosis
Iatrogenic trauma plexopathyIatrogenic trauma to the lumbosacral plexus can occur duringsurgical, gynecological, or anesthetic procedures. The mechanisms includecompression, traction, and vascular insult. Proper clinical and electrodiagnosticdifferentiation is important with such plexopathies since the prognosis dependson the cause and location.Surgical laceration injuries are rare, but among the most severe, since theprogress to recovery is not possible. It is most likely to occur during a deeppelvic procedure, such as a prostatic resection or a hysterectomy.Blunt trauma from surgical retraction or during forceps delivery is morecommon. The femoral and obturator nerves are the most frequently injured. Thelumbosacral trunk, lateral cutaneous nerve, and the sciatic nerves follow.Arthroplasty of the hip results in a significant number offemoral, obturator, and sciatic injuries through direct trauma, stretch, or theeffects of heat from cement polymerization. The chiropractor may be more apt tosee such a plexopathy resulting from an epidural anesthesia procedure. Anepidural may cause a rectoperitoneal hemorrhage that may result in adiffuse, extensive, and neuropathic injury.Another rare cause of iatrogenic lumbar plexopathy may be due to a pre-existing atherosclerosis, intraoperative hypotension, or coagulopathy, whichmay initiate a spinal artery syndrome. A spinal artery syndrome should alwaysbe considered in the case of unexplained postoperative weakness, particularly inthe elderly population.
Neoplastic PlexopathyNeoplastic plexopathy lesions originating in the pubic regions caninvade the lumbosacral plexus by direct expansion. The mostcommon is a colorectal carcinoma. However, uterine, prostatic, andovarian tumors can be locally invasive as well. Metastatic invasionsof the retroperitoneum and the lumbosacral plexus by breast,thyroid, testicular cancers, lymphomas, myelomas, and melanomasare also well known. Patients with neurofibromatosis can developgrossly huge tumors involving any compartment of the plexus.Neoplastic plexopathies generally present with unilateral pelvic painand, when progressive, show lower motor neuron signs. Weakness:Proximal Unilateral; AsymmetricProgression: RapidPain: Often severeMass: Palpable rectalCancer type: Colon; Prostate; SarcomaImaging: Focal mass
Extrinsic tumor. STIR MR image in a patient with carcinoma of the cervixshowing an extensive soft tissue mass surrounding and infiltrating the entirepelvis and the sacral plexus bilaterally (arrow) that is enlarged with loss of fatplanes and normal fascicular architecture. Note the hyperintense signalconsistent with extensive marrow infiltration by the mass lesion.
Immune (vasculopathy) plexopathyOnset: Late-ageClinical features : Sensory Pain: Variable; Occasionally severe Sensory Loss: Distal; Often asymmetric Weakness : Asymmetric, Proximal, Distal or Both Bilateral Course: Progression over weeks to monthsAssociation: DiabetesLaboratory : EMG: Denervation in limbs & paraspinous muscles Nerve biopsy Inflammatory cells around small epineurial blood vessels Differential fascicular loss of axons High sedimentation ratePrognosis: Recovery with treatment Over months to yearsTreatment: Corticosteroids Intravenous Ig
Ischemic Lumbosacral plexopathyBlood supply of lumbar & sacral plexus: Branches of the internal iliac arteryClinical: Symptoms & Signs mostly after exercise Exacerbated walking uphill No effect of bicycle exercise Distribution: Unilateral or bilateral Exercise provocation: Walking uphill; Riding a bicycle Examination at rest often normal Sensory Pain: Gluteal region after exercise; 85% Paresthesias Sensory Loss: Pan-modal; Not dermatomal; Distal or Proximal Weakness: Distal ± Proximal Leg Tendon reflexes: May be reduced after exerciseElectrodiagnostic: EMG & NCV often normal Pelvic arteriography Bilateral stenoses of the internal iliac arteries (75%) Other stenosis Distal abdominal aorta + bilateral common iliac artery Ipsilateral internal & common iliac arteryTreatment: Percutaneous transluminal angioplasty; Stents