Brachial Plexus Injury

Upper Limb

Overview

Brachial plexus injury involves damage to the nerve network (C5-T1) that controls upper limb function, resulting from trauma, stretching, or compression. Injuries range from mild neurapraxia to complete nerve root avulsion, presenting with varying degrees of motor weakness, sensory loss, and pain. Prognosis depends on injury severity, mechanism, and timing of intervention.

Pathophysiology

The brachial plexus can be damaged through traction injuries (shoulder depression with neck extension), compression injuries (cervical rib, scalene muscle hypertrophy, fibrous bands), penetrating trauma, or nerve root avulsion from the spinal cord. Nerve injury triggers inflammatory cascades, axonal degeneration, and disruption of motor and sensory signals. In traction injuries, nerve fibers may be stretched beyond their elastic limit, causing demyelination (neurapraxia) or axonal disruption (axonotmesis), or complete nerve root avulsion (neurotmesis). Chronic cases may develop neurogenic inflammation, muscle atrophy, and complex regional pain syndrome.

Patient Education

Brachial plexus injuries require prompt assessment and specialist neurological evaluation; early intervention, gentle mobilisation, and structured rehabilitation maximise recovery and prevent secondary complications like muscle contracture and chronic pain.

Typical Presentation

Site

Upper limb including shoulder, arm, forearm, hand; pain may radiate from neck to fingers; distribution depends on which nerve roots are involved

Quality

Sharp, burning, shooting, or electric pain; numbness and tingling; heaviness or weakness sensation

Intensity

Highly variable (0-10/10) depending on injury severity; acute injuries often severe; chronic injuries may present with dull ache

Aggravating

Neck movement away from injury side, shoulder depression, arm elevation, certain work activities, sustained postures, Adson's test position (neck extension with arm abduction)

Relieving

Arm support in sling, neck lateral flexion toward injury, rest, ice in acute phase, gentle arm movements

Associated

Motor weakness (variable by nerve root: C5 shoulder abduction/external rotation, C6 elbow flexion, C7 elbow extension, C8-T1 hand grip), sensory loss in dermatomal pattern, swelling, muscle atrophy (develops over weeks), colour changes, temperature changes, Horner's syndrome if T1 root involved, hand weakness and clumsiness

Orthopaedic Tests

Upper Limb Tension Test (ULTT) / Nerve Stretch Test

Procedure

Patient supine; sequentially abduct the shoulder to 90°, externally rotate, extend the elbow, and dorsiflex the wrist while the examiner stabilizes the scapula. Sensitizing maneuvers include cervical contralateral side-bending.

Positive Finding

Reproduction of radicular pain, paraesthesia, or neural symptoms in the distribution of the affected nerve root(s); comparison with the unaffected limb.

Sensitivity / Specificity

72–85% / 60–80%

Coppieters & Altenwerth, 2007, Manual Therapy; Wainner et al., 2003, JOSPT

Interpretation

Suggests neural tension or nerve root involvement; high sensitivity for detecting brachial plexus irritation, though not specific to plexus injury alone. Useful for differential diagnosis of cervical root pathology.

Spurling's Test (Cervical Compression & Extension)

Procedure

Patient seated; examiner applies gentle downward compression on the head while the cervical spine is extended and rotated toward the affected side. Hold for 30 seconds.

Positive Finding

Immediate sharp radicular pain radiating into the upper limb corresponding to the nerve root distribution.

Sensitivity / Specificity

50–75% / 72–95%

Tong et al., 2002, Manual Therapy; Viikari-Juntura et al., 2000, Spine

Interpretation

High specificity for cervical nerve root compression (C5–C6 most common); positive result strongly suggests nerve root involvement as a source of brachial plexus symptoms. Helps differentiate root-level pathology.

Adson's Test (Thoracic Outlet Syndrome / TOS Screen)

Procedure

Patient seated or supine; shoulder abducted 90° and externally rotated; patient extends neck and rotates head toward the affected side while taking a deep breath. Examiner monitors radial pulse.

Positive Finding

Disappearance or significant diminution of the radial pulse on the affected side; reproduction of paraesthesia, pain, or heaviness in the arm.

Sensitivity / Specificity

20–72% / 50–96%

Povlsen et al., 2014, European Journal of Neurology; See current literature for sensitivity variation

Interpretation

Suggests vascular or neural compression at the thoracic outlet; useful for screening TOS as a differential diagnosis or contributing factor in brachial plexus symptoms, though low–moderate sensitivity limits its stand-alone diagnostic value.

Tinel's Sign at the Brachial Plexus

Procedure

Examiner percusses gently along the course of the brachial plexus, particularly in the supraclavicular fossa and axilla, using a small reflex hammer.

Positive Finding

Sudden 'tingling' or 'pins and needles' sensation radiating distally into the forearm and hand in the distribution of the plexus.

Sensitivity / Specificity

25–40% / null

See current literature; classically described in peripheral nerve examination

Interpretation

May indicate nerve regeneration or irritation at a specific point along the plexus; low sensitivity but helpful if present. Absence does not rule out plexus injury.

Phrenic Nerve Involvement Screen (Shoulder Abduction Test)

Procedure

Patient supine; examiner assesses diaphragmatic motion using fluoroscopy or ultrasound while patient performs deep inspiration, or observes for asymmetrical chest wall movement and abdominal breathing patterns.

Positive Finding

Ipsilateral elevated hemidiaphragm, reduced diaphragmatic excursion (fluoroscopy <1 cm), or paradoxical breathing patterns; C3–C4–C5 root involvement.

Sensitivity / Specificity

null / null

See current literature; standard neurological examination technique

Interpretation

Indicates proximal brachial plexus injury (upper trunk/root level); helps localize injury to C3–C5 and assess severity. Important for respiratory assessment in high plexus lesions.

Grip Strength Testing & Intrinsic Hand Muscle Assessment

Procedure

Use a dynamometer to measure grip strength bilaterally; assess for thenar (C8–T1) and hypothenar muscle atrophy. Perform resisted thumb opposition, finger abduction/adduction, and opposition testing.

Positive Finding

Asymmetrical grip strength (>10 kg difference), visible atrophy, or weakness of intrinsic hand muscles; lower trunk (Klumpke's palsy) pattern most notable.

Sensitivity / Specificity

null / null

See current literature; standard electrodiagnostic and clinical neurological assessment

Interpretation

Localizes plexus injury to lower trunk (C8–T1) if C8–T1 myotomes are affected; helps identify lower plexus or root avulsion injuries. Useful for monitoring progression/recovery.

⚠ Red Flags

  • •Acute severe trauma with sudden complete arm paralysis requiring emergency referral
  • •Signs of Horner's syndrome including ptosis, miosis, and anhidrosis suggesting T1 avulsion with poor prognosis
  • •Severe progressive neurological deficit or rapidly worsening weakness
  • •Penetrating wound with visible nerve damage
  • •Fracture-dislocation of cervical spine or shoulder girdle
  • •Severe vascular compromise including cold limb, absent pulses, or severe swelling

⚡ Yellow Flags

  • •Significant psychological distress or catastrophising about permanent disability
  • •Fear of using affected limb leading to learned non-use and muscle atrophy
  • •Concurrent substance abuse potentially affecting compliance with rehabilitation
  • •High comorbidity of depression, anxiety, or chronic pain syndrome
  • •Unrealistic expectations regarding recovery timeline
  • •Poor motivation for rehabilitation exercises
  • •Occupational demands incompatible with injury severity
  • •Litigation or compensation claims that may perpetuate symptom focus

Osteopathic Techniques

Region

Cervical spine and nerve roots C5-T1

Technique

Soft Tissue

Rationale

Gentle soft tissue techniques to scalene muscles, levator scapulae, and upper trapezius reduce muscle guarding and improve neural mobility without compromising healing; reduces secondary entrapment at cervical level

Region

Cervical and upper thoracic spine

Technique

Articulation

Rationale

Gentle cervical articulation and mobilisation improves intervertebral foraminal opening, reduces nerve root compression, and enhances drainage; careful grading essential during acute phase

Region

Scalene triangle and thoracic inlet

Technique

Functional

Rationale

Functional technique to normalize scalene muscle tone and thoracic inlet mechanics reduces compression of upper brachial plexus; particularly effective for neurogenic thoracic outlet syndrome component

Region

Upper limb including shoulder girdle and arm

Technique

MET

Rationale

Muscle energy technique improves shoulder girdle stability and reduces protective muscle tension; proprioceptive feedback supports neural re-education and prevents immobility-related stiffness

Region

Brachial plexus pathway and surrounding tissues

Technique

Lymphatic

Rationale

Gentle lymphatic drainage techniques reduce post-traumatic swelling and inflammation; improves local circulation to support nerve healing and reduces chemically-mediated pain

Region

Cranial base and cervical fascia

Technique

Cranial

Rationale

Subtle cranial techniques support autonomic balance, reduce neural irritability, and improve cerebrospinal fluid circulation; helpful for managing associated pain and promoting parasympathetic tone during recovery

Add-On Approaches

Chinese Medicine

TCM approach includes acupuncture to GB-21, TE-14, LI-10, LI-11 to improve qi flow and blood circulation; moxibustion may support warming and nerve recovery; herbal medicine (e.g., formulas containing Angelica, Rehmannia) addresses qi deficiency and pain

Chiropractic

Cervical spine manipulation and mobilisation to improve foraminal clearance; assessment of cervical posture and shoulder mechanics; may include upper thoracic adjustments if restrictive

Physiotherapy

Structured progressive strengthening programme for rotator cuff and scapular stabilisers; proprioceptive neuromuscular facilitation (PNF) patterns; electrical stimulation to denervated muscles in severe cases; mirror therapy for complex regional pain syndrome; functional retraining for activities of daily living

Remedial Massage

Deep soft tissue massage to scalenes, upper trapezius, levator scapulae; trigger point release to reduce secondary muscle tension; myofascial release to improve tissue mobility; progressive massage as healing progresses; avoid aggressive pressure in acute phase

Rehabilitation Exercises

Pendulum Swings (Codman's Exercise)

Range of MotionBeginner

Passive Arm Elevation with Opposite Hand

Range of MotionBeginner

Neck Lateral Flexion Stretch (Away from Affected Side)

StretchingBeginner

Scalene Muscle Stretch with Upper Trapezius

StretchingBeginner

Scapular Retraction and Depression

PosturalBeginner

Isometric Shoulder Abduction

StrengtheningIntermediate

Supine Shoulder External Rotation with Pillow

StrengtheningIntermediate

Prone Shoulder Flexion (Y-position)

StrengtheningIntermediate

Rotator Cuff Strengthening: Side-Lying External Rotation

StrengtheningIntermediate

Proprioceptive Upper Limb Positioning and Weight Shifting

BalanceIntermediate

Seated Posture Correction with Cervical Alignment

PosturalBeginner

Progressive Grip Strengthening with Therapy Ball

StrengtheningAdvanced

Referral Criteria

  • •Acute severe injury with complete arm paralysis: refer immediately to emergency department and neurosurgeon
  • •Suspected nerve root avulsion: urgent specialist imaging (MRI, EMG/NCS) and neurosurgical assessment
  • •Horner's syndrome or T1 involvement: specialist assessment for potential nerve transfer surgery
  • •Penetrating injury with nerve involvement: immediate surgical exploration
  • •Vascular compromise with limb at risk: immediate vascular surgery assessment
  • •Lack of improvement after 3 months of conservative care: refer to nerve specialist for advanced imaging and electrodiagnostic testing (EMG/NCS)
  • •Development of complex regional pain syndrome: pain specialist and physiotherapy with proven CRPS protocols
  • •Progressive muscle atrophy with functional decline: reassessment for possible surgical intervention (nerve grafts, transfers)
  • •Severe psychological impact or depression affecting recovery: referral to psychologist or counsellor
  • •Occupational/functional demands requiring specialist vocational assessment: occupational therapist for work conditioning