Brachial Plexus Birth Palsy

Newborn / By

Brachial Plexus Birth Palsy – Introduction

  • Brachial plexus – Normal brachial plexus, including locations of the nerves.Copyright ©2015 EBSCO Information Services.
  •  injury to nerve fibers in brachial plexus identified in neonates, with consequent weakness of affected upper extremity muscles(1,2,3)
  • brachial plexus is nerve network that supplies innervation to upper extremity and shoulder(2)
    •  extends from spinal cord to axilla
    • classically consists of
      • 5 roots (C5-T1) (75%)
        •  additional contribution from C4 (“prefixed cord”) in 22%
        •  additional contribution form T2 in 1% (“postfixed cord”)
      •  3 trunks (upper, middle, lower)
      •  6 divisions (anterior and posterior for each trunk)
      •  3 cords (lateral, posterior, medial)
      •  5 terminal nerves (axillary nerve, musculocutaneous nerve, median nerve, radial nerve, ulnar nerve)

Synonyms

  • Birth-related brachial plexus palsy
  • Neonatal brachial plexus injury
  • Obstetric brachial plexus palsy
  • Congenital brachial plexus palsy

Types

  •  neuropraxia – loss of myelin, good prognosis(2)
  •  axonotmesis – axon is disrupted and Wallerian degeneration occurs distally from the injury site, recovery variable(2)
  •  neurotmesis – complete disruption of axons, endoneurium, perineurium, and epineurium, require microsurgical procedures for recovery(2)
  •  avulsion – requires microsurgical procedures for recovery(2)

Epidemiology

Incidence/Prevalence

  •  0.4-4 children per 1,000 live births(1,2,3)

Likely Risk Factors

  • 50% of patients with brachial plexus birth palsy do not have any risk factors accounting for their injury(1,2)
  • maternal risk factors include(1,3)
    • gestational diabetes mellitus (GDM)
    •  excessive weight gain during pregnancy
    •  previous deliveries of infant with brachial plexus injuries
    •  pregnancies in multiparous women
  • labor-related risk factors include(1,2)
    • shoulder dystocia
    •  prolonged labor
    •  instrumented delivery
    •  tachysystole (defined as > 6 contractions in 10 minutes or one large contraction lasting more than 2 minutes)
    •  oxytocin use
  • fetal risk factors(2)
    •  macrosomia (most common)
    •  fetal distress resulting in hypotonia
    •  decreased fetal arm movements (may lead to atrophy and more vulnerability to stretch forces)
    •  presence of first cervical rib
    •  clavicular fracture (may be associate condition, not risk factor)
  • shoulder dystocia and brachial plexus birth injury in previous deliveries each associated with increased risk of brachial plexus birth injury
    •  based on retrospective cohort study
    • 6,286,324 neonates delivered by 4,104,825 gestating parents aged 13-50 years (mean age 28 years) in 1996-2012 in nonfederal California-licensed hospitals were assessed
    • baseline characteristics of gestating parents
      • 44% were multiparous
      • 0.14% had prior delivery of neonate with shoulder dystocia
      • 0.052% had prior delivery of neonate with brachial plexus birth injury
    • 7,762 neonates (0.12%) had brachial plexus birth injury
    • comparing brachial plexus birth injury vs. no brachial plexus birth injury in neonates born to multiparous gestating parents
      • shoulder dystocia in previous delivery in 1.67% vs. 0.33% (adjusted odds ratio 5.39, 95% CI 4.1-7.08)
      • brachial plexus birth injury in previous delivery in 1.92% vs. 0.14% (adjusted odds ratio 17.22, 95% CI 13.31-22.27)
    • Reference – Obstet Gynecol 2023 Nov 1;142(5):1217
  • shoulder dystocia, infant weight ≥ 3,999 g, administration of fundal pressure associated with brachial plexus birth palsy among infants delivered by vacuum extraction
    •  based on retrospective cohort study
    •  13,716 women who delivered by vacuum extraction evaluated
    •  153 infants (1.1%) had obstetric brachial plexus palsy
    • risk of obstetric brachial plexus injury increased with
      • shoulder dystocia (odds ratio [OR] 16, 95% CI 8.9-28.7)
      •  fetal birth weight ≥ 3,999 g (OR 7.1, 95% CI 4.8-10.5)
      •  administration of fundal pressure (OR 1.6, 95% CI 1.1-2.3)
    •  Reference – Obstet Gynecol 2005 Nov;106(5):913

Possible Risk Factors

  • No consensus regarding characteristics of second stage of labor (such as duration) as risk factor for obstetric brachial plexus injury(1,2,3)

Factors Not Associated With Increased Risk

  • Breech presentation(2)

Factors That May Decrease Risk

  • factors that may decrease risk(1,2,3)
    •  cesarean delivery (incidence 0.2% without cesarean vs. 0.02% with cesarean)
    •  twin or multiple birth
    •  prematurity
    •  fetal growth restriction
  • higher maternal parity and cesarean birth in multiparous gestating parent each associated with reduced risk of brachial plexus birth injury
    •  based on retrospective cohort study
    • 6,286,324 neonates delivered by 4,104,825 gestating parents aged 13-50 years (mean age 28 years) in 1996-2012 in nonfederal California-licensed hospitals were assessed
    • baseline characteristics of gestating parents
      • 44% were multiparous
      • 0.14% had prior delivery of neonate with shoulder dystocia
      • 0.052% had prior delivery of neonate with brachial plexus birth injury
    • 7,762 neonates (0.12%) had brachial plexus birth injury
    • higher parity associated with decreased risk of brachial plexus birth injury (adjusted odds ratio for each subsequent delivery 0.94, 95% CI 0.92-0.97)
    • adjusted risk of brachial plexus birth injury per 100,000 live births comparing cesarean birth vs. vaginal delivery in multiparous gestating parents
      • overall 18.9 vs. 150.3 (p < 0.001)
      • with no shoulder dystocia or brachial plexus birth injury in previous delivery 18.3 vs. 145.8 (p < 0.001)
      • with shoulder dystocia in previous delivery 78.4 vs. 620.2 (p < 0.001)
      • with brachial plexus birth injury in previous delivery 306.7 vs. 2,387.3 (p < 0.001)
    • Reference – Obstet Gynecol 2023 Nov 1;142(5):1217

Associated Conditions

  • Clavicle or humerus fracture(2)
  • Concomitant cerebral palsy (CP)(2)

Etiology and Pathogenesis

Causes

  • trauma during delivery(1)
    • increased stretch force during delivery
      •  most common mechanism
      •  occurs during delivery complicated by shoulder dystocia or instrumental vaginal delivery
      •  probably contributes to damage produced by other mechanisms
    •  compression
    •  oxygen deprivation may occur
  • other causes(1)
    • intrauterine maladaption
      •  presents as brachial plexus palsy without significant traction forces at time of delivery
      •  thought to be due to forces generated during uterine contractions
    • maternal uterine malformation
      •  uterine malformations (such as bicornate uterus) have been associated with brachial plexus palsy
      •  diagnosed only if proven maternal uterine malformation and exclusion of injury during delivery
    • familial congenital brachial plexus palsy
      •  patients have family history of brachial plexus palsy
      •  characterized by arm deformity at birth
      •  unclear inheritance pattern (no chromosomal abnormalities detected)
      •  unclear mechanism of injury
    •  congenital varicella syndrome
    • humeral or vertebral osteomyelitis
      •  osteomyelitis due to group B streptococcus infection can cause ischemia to plexus
      •  characterized by sudden arm weakness several days after birth
      •  infants may have sensitivity to motion and palpation
      •  bone scan is diagnostic study of choice
    • exostosis of first rib
      •  diagnosis confirmed with x-ray
    • brachial plexus tumors – rare
      •  neurofibroma
      •  rhabdoid tumors
      •  myofibroma
    • hemangioma – rare
      •  may be isolated condition or part of systemic disease
      • palsy may be due to either
        •  compression by hemangioma
        •  shunting of blood to hemangioma causing oxygen deprivation to brachial plexus

Pathogenesis

  • increased stretch force on brachial plexus may be due to either or both of(1)
    •  propulsive forces during labor
    •  traction forces during difficult delivery
  •  related oxygen deprivation may contribute to nerve palsy(1)

History and Physical

Clinical Presentation

  •  observed weakness of affected arm at or soon after birth(1,2)
  •  injury classification by nerve involvement(2)
  • different patterns of nerve damage result in different clinical presentations(2)
    •  Erb palsy (60%-70%) – asymmetrical arm movement with C5-C6 injury
    • Erb plus palsy or extended Erb palsy (also called “waiter’s tip” position) (20%-30%) with C5-C7 injury
      •  adduction and internal rotation of arm
      •  extension and pronation of forearm
      •  flexion of wrist and fingers
    •  flail arm and Horner syndrome (total or global brachial plexus palsy) (15%-20%) with C5-T1 injury
    •  Klumpke palsy (isolated paralysis of hand and Horner syndrome) (< 1%) with C8-T1 injury

History

Past Medical History (PMH)

  •  ask about maternal diabetes(1,2)
  • relevant labor and delivery history includes(1,2)
    •  history of difficulty during delivery
    •  APGAR score (to assess possible cerebral anoxia)
    •  instrumental delivery

Family History (FH)

  •  ask about family history of brachial plexus palsy(1,2)

Physical

Chest

  •  examine for clavicle fracture(2)

Extremities

  •  examine for humerus fracture(2)

Neuro

  • lack of movement about the shoulder, elbow, wrist, and/or digits may be observed at rest or with provocative testing such as(2)
    •  tactile stimulation
    •  Moro reflex (sudden neck extension usually causes shoulders to abduct, elbows to extend, and fingers to extend and spread)
    •  asymmetric tonic neck reflex (turning infant’s head to the side with arm and leg extending on side the head is turned to usually causes flexion of contralateral arm and leg [“fencer position”])
  • assess for presence of Horner syndrome(2)
    • look for triad of signs on affected side
      •  ptosis (drooping eyelid)
      •  miosis (pupil constriction) creating anisocoria (unequal pupil size)
      •  facial anhidrosis (lack of sweating)
  •  presence of spasticity may indicate perinatal anoxia(2)

Assessment Scores

  •  Toronto Test Score, Active Movement Scale, and modified Mallet system all shown to have good intra- and interobserver reliability with aggregate scores(2,3)
  • modified Mallet system (most commonly used)(2)
    • categories include
      •  global abduction
      •  global external rotation
      •  hand to neck
      •  hand to mouth
      •  hand to spine
      •  hand to navel
    •  each category graded on scale from 0 (not testable) to 5 (normal)
  • Toronto Test Score(2)
    • upper extremity functions evaluated
      •  shoulder abduction
      •  elbow flexion
      •  wrist extension
      •  digit extension
      •  thumb extension
    • grading scale
      •  0 – no function
      •  1 – partial function
      •  2 – normal function
      •  if combined score < 3.5 by 3 months of age or older, microsurgery indicated
  • Active Movement Scale(2)
    •  15 different upper extremity movements evaluated with gravity eliminated and then against gravity
    •  each movement scored from 0 to 7

Diagnosis

Making the Diagnosis

  •  physical exam is diagnostic if arm weakness with distribution consistent with brachial plexus injury at birth observed at rest or with provocative testing(1,2)
  • different patterns of nerve damage result in different clinical presentations(1,2)
    • C5-C6 injury results in Erb palsy (60%-70%)
      •  adduction and internal rotation of arm
      •  extension and pronation of forearm
    • C5-C7 injury results in extended Erb palsy (“waiter’s tip” position)
      •  adduction and internal rotation of arm
      •  extension and pronation of forearm
      •  flexion of wrist and fingers
    •  C5-T1 injury results in Erb palsy with some finger flexion sparing
    •  C5-T1 injury results in flail arm and Horner syndrome
    •  C8-T1 results in Klumpke palsy (isolated paralysis of hand and Horner syndrome) (20%-30%)
  •  several assessment scores can be used to define severity of injury

Differential Diagnosis

  •  pseudopalsy (movement resisted secondary to pain from associated fracture)(2)

Testing Overview

  • imaging
    •  routine imaging not usually required if recovery progressive(2)
    • specific imaging may be required if suspecting certain alternative diagnoses(1)
      •  x-ray for bone fractures
      •  bone scan is imaging of choice if osteomyelitis suspected
    • radiologic studies that demonstrate nerve root avulsions (preganglionic injuries) indicated for preoperative assessment(2)
      •  if large diverticula or frank myelomeningoceles identified, computed tomography myelography and magnetic resonance imaging have greater than 90% sensitivity for determining avulsion injuries correlated at surgery
  • electrodiagnostic studies
    •  electrodiagnostic studies, including nerve conduction velocity and needle electromyography, overestimate clinical recovery in proximal muscles of shoulder and arm and may provide false hope to parents and delay surgical intervention(2)
    • electromyographic studies(1)
      •  only practical tool for timing of brachial plexus injury
      •  findings in muscles innervated from proximal region of brachial plexus provide most reliable information
      • prepartum injury can be diagnosed when either
        •  fibrillations present during first day of extrauterine life and duration of labor < 24 hours
        •  large motor unit potentials or nascent motor unit potentials present during first 10 days of life
      •  intrapartum injury can be diagnosed when fibrillations are absent during first 10 days of extrauterine life and appear in second study performed days later

Management

Management Overview

  •  initial treatment of all brachial plexus nerve palsies is passive range of motion performed multiple times a day at home (unless coexistent fracture, then wait 3-4 weeks)
  • options for patients with persistent muscle imbalance include
    • botulinum toxin
      •  can be used to reduce muscle tone to assist passive range of motion and joint alignment
      •  limited evidence for efficacy
    • nerve microsurgery
      • surgery before 3 months associated with improved functional outcomes for axillary nerve reconstruction compared to surgery at older age (level 2 [mid-level] evidence)
      • earlier age at microsurgical reconstruction associated with improved functional hand assessment (level 2 [mid-level] evidence)
    • other surgical options include
      •  arthroscopic release and open release with or without tendon transfer each associated with similar improvement in both external rotation and aggregate Mallet score (level 2 [mid-level] evidence)
      • tendon transfer (most commonly performed around shoulder)
      • osteotomies (humeral derotational osteotomy usually performed in older children for treatment of glenohumeral dysplasia)

Activity

  •  perform range of motion (ROM) exercises multiple times a day at home(2,3)
  •  arrange formal therapy sessions as needed for education and assessment(2,3)
  • passive range of motion can prevent contractures(2,3)
    •  if no fracture, begin immediately
    •  if fracture present, begin at healing (about 3 weeks)
    •  stabilize shoulder to maximize true glenohumeral motion
  • in infants with upper obstetric brachial plexus palsy, 3 times daily and once daily exercise program may have similar efficacy for recovery of ROM and muscle strength by age 12 months (level 2 [mid-level] evidence)
    •  based on pilot randomized trial without power calculation for sample size estimation
    • 60 infants (mean age 7.5 days) with upper brachial plexus birth palsy were randomized to 3 times daily vs. once daily exercise program and followed through age 12 months
    • exercises included passive ROM exercises targeting all joints of upper extremities initially, followed by active ROM and muscle enhancement exercises in subsequent months; duration of exercise was dependent on child’s cooperation
    • assessments included passive-active ROM and muscle testing
    • 4 infants who had weak biceps muscle force at age 4 months were referred to surgery and excluded from trial
    • both exercise groups had significant improvement in
      • active ROM in shoulder abduction, external rotation and flexion, and elbow flexion and forearm supination through age 12 months
      • active ROM in shoulder internal rotation and extension through age 6 months
      • muscle strength in shoulder abduction, shoulder flexion, elbow flexion, and forearm supination through age 12 months
    • no significant differences between exercise groups at age 3, 6, or 12 months in any ROM measures or muscle force assessments
    • no complications reported in either group
    • Reference – North Clin Istanb 2019;6(1):1full-text
  •  perform tactile stimulation to allow cortical recognition and integration of affected limb(2,3)
  • during participation in sports, children and adolescents with residual deficits may have(3)
    •  lower global function
    •  perception of limitations
    •  symptoms in affected limb
    •  no increased rate of injury

Medications

  • botulinum toxin type A(3)
    •  can be used to reduce muscle tone to assist passive range of motion and joint alignment
    • limited evidence for efficacy regarding
      •  prevention of contractures in immediate postoperative period after microsurgery
      •  adjunctive treatment to physical therapy
      • botulinum toxin reported to produce sustained clinical improvement in elbow function but not shoulder function in patients with brachial plexus birth palsy with persistent muscle imbalance (level 3 [lacking direct] evidence)
        •  based on retrospective case series
        •  27 patients with brachial plexus birth palsy and persistent muscle imbalance were treated with botulinum toxin and evaluated after 1 year
        •  patients had mean age 36.2 months +/- 28.2 months
        •  17 patients (63%) had prior plexus reconstruction
        • in 19 patients with shoulder imbalance, mean Active Movement Scale scores for shoulder external rotation
          •  0.6 at baseline
          •  2.6 (p < 0.01) at 1 month
          •  1.3 (p < 0.01) at 1 year
        • in 8 patients with elbow imbalance, mean Active Movement Scale scores
          • for elbow flexion
            •  3.3 at baseline
            •  not significantly different at 1 month
            •  5.8 (p < 0.01) at 1 year
          • for elbow supination
            •  2.9 at baseline
            •  not significantly different at 1 month
            •  3.9 (p < 0.01) at 1 year
        •  Reference – Plast Reconstr Surg 2013 Jun;131(6):1307

Surgery and Procedures

Nerve Microsurgery

  • indications and timing of surgery(2,3)
    •  for infants with global plexus palsies and Horner syndrome, consensus is for microsurgical intervention at about 3 months of age
    • no consensus for patients with typical or extended Erb palsy
      •  some clinicians consider surgery indicated if no elbow flexion against gravity is present by 3 months of age
      •  equivalent functional outcome reported in infants who regained elbow flexion against gravity between 4 and 6 months of age combined with secondary tendon transfer
      •  surgery delayed up to 9 months of age in some instances to allow for possibility of recovery
    • surgery before 3 months associated with improved functional outcomes for axillary nerve reconstruction compared to surgery at older age (level 2 [mid-level] evidence)
      •  based on cohort study
      • 56 patients had nerve reconstruction for obstetrical palsy with mean 5.5 years follow-up
        •  9 (16%) patients had classic Erb palsy
        •  13 (23%) patients had extended Erb palsy
        •  34 (61%) had global palsy
      • timing of surgery
        •  age < 3 months in 9 patients (16%)
        •  between 4 and 6 months in 24 patients (43%)
        •  > 6 months in 23 patients (41%)
      •  compared with surgery at age > 3 months, surgery at ≤ 3 months associated with improved shoulder abduction and external rotation scores (p < 0.001)
      •  Reference – Plast Reconstr Surg 2008 Nov;122(5):1457
    • earlier age at microsurgical reconstruction associated with improved functional hand assessment (level 2 [mid-level] evidence)
      •  based on cohort study
      •  35 infants with total obstetric brachial plexus palsy had brachial plexus exploration and reconstruction and followed for ≥ 2.5 years (range 2.5 -7.3 years)
      •  compared with later age at surgery, earlier age at surgery associated with improved functional hand assessment (mean Raimondi score) (p < 0.049)
      •  Reference – Microsurgery 2010;30(3):169
    • microsurgery during infancy age 2-11 months associated with better outcomes for hand function than surgery after 1 year (level 2 [mid-level] evidence)
      •  based on retrospective cohort study
      •  78 infants with obstetrical brachial plexus palsy had microsurgery with 4 years of follow up
      •  68 patients had surgery during the infant period (2-11 months) and 10 patients had surgery later
      •  2 of 10 patients having surgery after 1 year had improved hand function after surgery
      • 28 of 44 patients with rupture and avulsion injury had good hand function after surgery
        •  35 had surgery before 1 year
        •  9 had surgery after 1 year
      • comparing patients operated on before 1 year vs. after 1 year
        •  good finger function in 71.4% vs. 33.3%
        •  fair finger function in 25.7% vs. 44.4%
        •  poor finger function in 2.9% vs. 22.2%
      •  no significant differences between patients who had early or late surgery in improvement in shoulder and elbow function
      •  Reference – Plast Reconstr Surg 2005 Jul;116(1):132
      • CLINICIANS’ PRACTICE POINT: The authors conclude that the need for surgery by 3 months may not be as necessary if there is no involvement of hand function and the impairment is only at the level of the shoulder and elbow.
    • older infants who pass the “cookie test” but have poor spontaneous recovery of active shoulder movements, particularly external rotation, reported to benefit from primary nerve surgery (level 3 [lacking direct] evidence)
      •  based on case series
      •  17 patients with brachial plexus birth palsy who did not meet standard criteria for surgical intervention were offered surgery at mean age 10.3 months and were followed for mean 23 months
      •  all 17 patients were identified as having poor shoulder function at age 9 months despite passing “cookie test” (ability to bring cookie from hand to mouth), and 16 had no active external rotation
      •  3 families declined surgery
      •  all 13 patients who had surgery and long-term follow-up data regained some active external rotation following surgery, ranging from 2 to 7 on the active movement scale
      •  5 of the 13 required further interventions (either botulinum toxin injections or additional surgery)
      •  Reference – Biomed Res Int 2014;2014:627067full-text
  • procedure options(2,3)
    •  neuroma resection and nerve grafting (most widely used)
    • nerve transfer and nerve conduits (increasing use)
      •  avoids use of donor nerve
      •  neurorrhaphy performed close to motor end plate (reinnervation time minimized)
      • Erb palsy (C5 and C6 root injuries) can be treated with “triple” nerve transfer
        •  long or lateral head of triceps branch of radial nerve to the axillary nerve
        •  ulnar nerve fascicle of flexor carpi ulnaris to the biceps motor nerve
        •  spinal accessory nerve to suprascapular nerve
        •  additional benefit with median nerve transfer (using fascicles to flexor carpi radialis transferred to musculocutaneous nerve innervation of brachialis muscle)
      •  synthetic collagen nerve conduits may be useful for select short segment brachial plexus repairs, but limited data available
    • nerve grafting and nerve transfer may have similar functional recovery of elbow flexion in infants having reconstruction for brachial plexus birth injury (level 2 [mid-level] evidence)
      •  based on systematic review of observational studies
      • systematic review of 5 observational studies comparing nerve grafting vs. nerve transfer in 194 infants having reconstruction for brachial plexus birth injury
        • injuries involved C5-C7 in 3 studies, C5-C6 in 1 study, and C5-T1 in 1 study
        • sural nerve grafting was used in 3 studies reporting this data
        • nerve transfer involved ulnar or median nerves in 2 studies, ulnar nerve in 2 studies, and intraplexal nerve transfer of C6 in 1 study
      • mean patient age at surgery ranged from 5.7 to 11.9 months where reported
      • mean follow-up ranged from 12 to 70 months
      • functional recovery of elbow flexion was defined as ≥ 3 points on Medical Research Council scale or ≥ 5 points on Active Movement Scale
      • no significant difference in rates of functional recovery of elbow flexion (96.4% with nerve grafting vs. 95.2% with nerve transfer; odds ratio 1.15, 95% CI 0.19-7.08) in analysis of 3 studies with 118 children
      • in 1 study with 26 patients reporting complications, secondary orthopedic procedures were required in 58% of nerve graft patients vs. 14% of nerve transfer patients, with no donor site morbidity after sural nerve graft harvesting
      • Reference – Childs Nerv Syst 2019 Jun;35(6):929
  • outcomes(2)
    •  best results in reconstructions performed for upper plexus injuries
    •  good return of shoulder function in 60% to 80%
    •  elbow flexion against gravity occurs in 80% to 100%
  •  review of brachial plexus reconstruction for neonatal brachial plexus injury can be found in Plast Reconstr Surg 2009 Dec;124(6 Suppl):e370

Surgery for Shoulder Complications

Tendon Transfers
  •  secondary procedure for brachial plexus birth palsy(2)
  • can be performed(2)
    •  in isolation for incomplete natural recovery
    •  following primary microsurgical nerve procedure to further enhance function
  • most common procedures are around shoulder region(2,3)
    •  tendon transfer improves external rotation and abduction to correct internal rotation secondary to muscle imbalance
    •  transfer of the latissimus dorsi and teres major tendons to rotator cuff footprint area improves shoulder function but does not improve any underlying glenohumeral joint dysplasia
  •  assessment of midline function before tendon transfer is important as loss of midline function limits performance of activities of daily living (such as perineal care, dressing)(2)
  • C5-C7 injuries may result in further denervation of internal rotators, such as(2)
    •  lower subscapularis
    •  midportion of pectoralis major
    •  latissimus dorsi muscles
  • shoulder tendon transfers improve shoulder function, active shoulder abduction and external rotation in children with brachial plexus birth palsy (level 2 [mid-level] evidence)
    •  based on prospective cohort study
    •  23 children aged 4-12 years with brachial plexus birth palsy evaluated before and after external rotation tendon transfers of shoulder
    • tendon transfers resulted in improvement of
      •  range of active shoulder abduction by 35 degrees (p < 0.001)
      •  range of active external rotation by 41 degrees (p < 0.001)
      •  upper extremity function score by 12 points (p < 0.001)
      •  sports function score by 4 points (p = 0.04)
      •  global function score by 6 points (p = 0.001)
    •  Reference – J Pediatr Orthop 2008 Mar;28(2):259
Osteotomies
  • humeral derotational osteotomies(2,3)
    •  usually performed in older children for treatment of glenohumeral dysplasia
    •  places the limb in more functional position but does not improve overall arc of motion
    •  allows flexion of elbow to mouth without bringing arm away from body (trumpeter’s or hornblower’s sign)
    •  deltopectoral and medial approaches have low complication rates
  •  glenoid anteversion osteotomies with tendon transfers may be useful alternative (no long-term results available)(2)
  •  review of external rotation humeral osteotomy for brachial plexus birth palsy can be found in Tech Hand Up Extrem Surg 2007 Mar;11(1):8
Other Surgeries for Shoulder Complications
  • conjoint muscle transfer with subscapularis muscle slide surgery reported to improve shoulder function in children with brachial plexus birth palsy presenting with shoulder deformity and inadequate shoulder function (level 3 [lacking direct] evidence)
    •  based on case series
    • 18 children (mean age 4.6 years, 61% male) with brachial plexus birth palsy presenting with shoulder deformity and inadequate shoulder function had conjoint latissimus dorsi and teres major muscle transfer with subscapularis muscle slide surgery
    • shoulder function was assessed using modified Mallet scoring system (maximum score 25 points, with higher scores indicating better shoulder function)
    • mean preoperative modified Mallet score was 10.9 points
    • at follow-up of 18 months, all children had improvement in shoulder function
      • mean postoperative modified Mallet score was 16.2 points (p < 0.05 compared to preoperative score)
      • mean gain in active shoulder abduction was 57.2 degrees
      • mean gain in external rotation was 26.7 degrees
    • no significant association between age and measures of shoulder function or active range of motion
    • Reference – Med J Armed Forces India 2021 Apr;77(2):181
  • indications include(3)
    •  infantile dislocation
    •  persistent internal rotation contracture refractory to physiotherapy
    •  limitation of active abduction and external rotation function with plateauing of neural recovery
    •  progressive glenohumeral deformity
  • goals include(3)
    •  contracture release
    •  muscle rebalancing
    •  joint reduction
  • may be performed as open or arthroscopic procedure(2,3)
    • arthroscopic release and open release with or without tendon transfer each associated with similar improvement in both external rotation and aggregate Mallet score in patients with neonatal brachial plexus palsy
      •  based on systematic review and meta-analysis of observational studies
      •  405 patients in 17 cohort studies of patients with neonatal brachial plexus palsy who had soft-tissue shoulder operation reviewed
      • in pooled analysis
        • no significant differences between groups in success rates for improvement in
          •  aggregate Mallet scores
          •  external rotation Mallet scores
        •  comparing open technique vs. arthroscopic technique, global abduction Mallet score success rates 67.4% vs.27.7% (p < 0.0001)
      •  Reference – J Pediatr Orthop 2013 Sep;33(6):656

Consultation and Referral

  •  referral for further intervention if failure to improve appropriately or worsening of contracture(3)

Other Management

  • shoulder function outcomes with intensive rehabilitation program without surgery reported to be unaffected by whether recovery of biceps contraction was before or after age 3 months
    •  based on small cohort study
    •  22 patients with obstetric brachial plexus palsy who recovered biceps contraction between 1 and 8 months with intensive rehabilitation program without surgery were reviewed
    •  mean follow-up 8.2 years
    •  mean Mallet scores similar for 9 children who recovered biceps contraction at age ≤ 3 months and 13 children who recovered biceps contraction after age 3 months
    •  Reference – Ann Chir Plast Esthet 2013 Aug;58(4):327

Follow-up

  •  serial physical examinations needed to predict recovery and if additional interventions are needed(2,3)

Complications and Prognosis

Complications

  • glenohumeral dysplasia with glenoid retroversion and posterior humeral head subluxation(2,3)
    •  present in 60%-80% of children who do not recover full motor function
    •  may occur after shoulder internal rotation contracture due to imbalance between internal and external rotators
    •  deformity increases with age
    •  may be prevented with various tendon transfer procedures
  •  review of evaluation and management of shoulder problems in children with brachial plexus birth palsy can be found in J Am Acad Orthop Surg 2009 Apr;17(4):242

Prognosis

  • most affected infants have spontaneous recovery within first 6 to 8 weeks of life and have normal or near normal range of motion and strength(2,3)
    •  recovery rates vary and correlate with injury types
    •  10%-15% may have permanent weakness
  • if substantial recovery is not present by 3 months of age, may have(2,3)
    •  permanent range of motion limitations
    •  decreased strength
    • decreased size and girth of the affected limb
      •  > 37% of patients and families thought this difference was “very” or “extremely important” to them
  • preganglionic injury indicates worse prognosis(2,3)
    • may be indicated by associated loss of other motor nerve function
      •  sympathetic chain (leads to presence of Horner syndrome)
      •  phrenic nerve
      •  long thoracic nerve
      •  dorsal scapular nerve
      •  suprascapular nerve
      •  thoracodorsal nerves
  • worse prognosis with(3)
    •  nerve root avulsions
    •  presence of total plexopathy (with weakness, sensory loss, decreased tendon reflexes) in infancy
  • obstetrical brachial plexus palsy associated with worse health-related quality of life
    •  based on cohort study
    •  122 children (70 with obstetrical brachial plexus palsy and 52 age-matched children without any health problems) evaluated for health related quality of life with short parent form of Child Health Questionnaire (CHQ-PF28)
    •  compared with controls, children with obstetrical brachial plexus palsy had lower subscale scores on CHQ-PF28 (p < 0.05)
    •  Reference – Qual Life Res 2013 Nov;22(9):2617

Prevention and Screening

Prevention

  • training for effective management of shoulder dystocia associated with decreased incidence of brachial plexus birth palsy
    •  based on 2 before-and-after studies
    • shoulder dystocia management training associated with improved neonatal outcomes (level 2 [mid-level] evidence)
      •  based on before-and-after study
      •  29,025 live, term, singleton, cephalic-presenting deliveries (15,908 pretraining and 13,117 posttraining) at single facility evaluated for management and neonatal outcomes associated with shoulder dystocia
      •  training session comprised of single practical session covering shoulder dystocia risk factors, recognition, demonstration of resolution, documentation and practice management on shoulder dystocia mannequin
      •  shoulder dystocia in 2.04% pretraining vs. 2% posttraining (not significant)
      • comparing pretraining vs. posttraining deliveries
        •  composite neonatal injury 9.3% vs. 2.3% (p < 0.05)
        •  fracture of clavicle or humerus at birth in 1.9% vs. 0.8% (p < 0.05)
        •  brachial plexus injury at birth in 7.4% vs. 2.3% (p < 0.05)
        •  brachial plexus injury persisting at 6 months in 2.8% vs. 0.8% (p < 0.05)
        •  brachial plexus injury persisting at 12 months in 1.9% vs. 0.8% (p < 0.05)
        •  5 minute Apgar score < 7 in 3.7% vs. 2.3% (p < 0.05)
      • use of maneuvers comparing pretraining vs. posttraining deliveries
        •  McRoberts position in 29.3% vs. 87.4% (p < 0.001)
        •  suprapubic pressure in 27.8% vs. 45.4% (p < 0.001)
        •  internal rotation maneuver in 6.8% vs. 11.1% (p = 0.02)
        •  delivery of posterior arm in 7.4% vs. 19.8% (p < 0.001)
      •  Reference – Obstet Gynecol 2008 Jul;112(1):14
    • shoulder dystocia management training associated with reduction in risk for brachial plexus injury (level 2 [mid-level] evidence)
      •  based on before-and-after study
      •  11,862 live deliveries from 2003 to 2009 (6,269 pretraining and 5,593 posttraining) at single facility evaluated for brachial plexus injury following shoulder dystocia
      •  training included risk factor assessment, early recognition, documentation, and practice management on shoulder dystocia mannequin
      •  shoulder dystocia in 1.32% pretraining vs. 1.34% posttraining (not significant)
      •  among 158 cases of shoulder dystocia, brachial plexus injury occurred in 30% during pretraining period vs. 10.7% posttraining (p < 0.01)
      •  Reference – Am J Obstet Gynecol 2011 Apr;204(4):322.e1

Screening

  • universal screening as part of newborn checkup may detect brachial plexus palsy if absence of movement even with provocation by(2)
    •  tactile stimulation
    •  Moro reflex (sudden neck extension usually causes shoulders to abduct, elbows to extend, and fingers to extend and spread)
    •  asymmetric tonic neck reflex (turning infant’s head to the side with arm and leg extending on side the head is turned to usually causes flexion of contralateral arm and leg [“fencer position”])

Guidelines and Resources

Guidelines

Review Articles

  •  to search MEDLINE for (Brachial plexus birth palsy) with targeted search (Clinical Queries), click therapy, diagnosis, or prognosis

Patient Information

References

  1. Alfonso DT. Causes of neonatal brachial plexus palsy. Bull NYU Hosp Jt Dis. 2011;69(1):11-6PDF.
  2. Abzug JM, Kozin SH. Evaluation and Management of Brachial Plexus Birth Palsy. Orthop Clin North Am. 2014 Apr;45(2):225-232.
  3. Hale HB, Bae DS, Waters PM. Current concepts in the management of brachial plexus birth palsy. J Hand Surg Am. 2010 Feb;35(2):322-31.

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