Mononeuropathy

Other

Overview

Mononeuropathy is a disorder affecting a single peripheral nerve, causing weakness, numbness, or pain in the distribution of that nerve. Common sites include the median nerve (carpal tunnel), ulnar nerve (cubital tunnel), and radial nerve (radial tunnel syndrome). The condition results from compression, trauma, or inflammation of the affected nerve and requires careful clinical assessment to identify the specific nerve involved and underlying cause.

Pathophysiology

Mononeuropathy develops when a single peripheral nerve experiences compression, stretch, ischemia, or direct trauma that disrupts axonal conduction. Mechanical compression (e.g., at anatomical sites of natural narrowing) causes demyelination and axonal injury, leading to impaired nerve conduction velocity. Inflammatory responses and edema within the nerve's fascicles further compromise blood flow and nutrient delivery. Chronic compression can result in permanent axonal loss if the offending mechanism is not relieved. The severity of symptoms correlates with the degree of nerve fiber involvement and duration of compression.

Patient Education

Early diagnosis and conservative management of nerve compression syndromes can prevent permanent nerve damage; identifying and modifying the mechanical cause is essential to recovery.

Typical Presentation

Site

Specific nerve distribution; common sites include median nerve (palm, thumb, index and middle fingers), ulnar nerve (ring and little fingers, medial hand), radial nerve (dorsal thumb and hand), peroneal nerve (lateral lower leg, dorsum of foot), and femoral nerve (anterior thigh)

Quality

Burning, tingling, pins-and-needles (paresthesia), numbness, electric shock-like sensations, or aching pain along nerve distribution

Intensity

Mild to moderate paresthesia in early stages; severe pain or weakness in advanced compression; typically progressive if untreated

Aggravating

Repetitive activity involving the affected nerve, sustained postures that compress the nerve, direct pressure on the nerve pathway, prolonged gripping or fine motor tasks, nighttime (especially in carpal tunnel syndrome)

Relieving

Rest, immobilization or splinting of the affected area, ice application, elevation, nerve gliding exercises, activity modification, anti-inflammatory medication

Associated

Weakness in muscles innervated by the affected nerve, muscle atrophy with chronic compression, loss of sensation in the nerve's cutaneous distribution, reduced grip strength, clumsiness with fine motor tasks, symptoms worse at night or upon waking

Orthopaedic Tests

Tinel's Sign

Procedure

Percuss gently along the course of the affected nerve, moving distally from the site of suspected compression or injury. Observe for tingling or electric sensations distal to the percussion point.

Positive Finding

Reproduction of tingling, pins-and-needles sensation, or electric shock-like sensation in the distribution of the nerve distal to percussion

Sensitivity / Specificity

null / null

Interpretation

Suggests nerve regeneration, demyelination, or compression at the site of percussion. Low specificity; does not reliably confirm mononeuropathy but may localize the lesion. Presence of Tinel's sign in early nerve injury may indicate better prognosis for recovery.

Phalen's Test (Wrist Flexion Test)

Procedure

Patient holds both wrists in maximum palmar flexion (forarms horizontal) for 60 seconds with elbows extended. Observe for symptom reproduction in the hand.

Positive Finding

Reproduction of paresthesias, numbness, or tingling in the median nerve distribution (thumb, index, middle, and radial half of ring finger) within 60 seconds

Sensitivity / Specificity

72% / 95%

Hegedus et al., 2013, Physical Medicine and Rehabilitation

Interpretation

Highly specific test for carpal tunnel syndrome (median nerve mononeuropathy). A positive result substantially increases likelihood of median nerve compression at the wrist. Negative result does not exclude the condition.

Upper Limb Tension Test (ULTT) – Median Nerve Bias

Procedure

Patient supine; sequentially perform shoulder abduction to 90°, external rotation, elbow extension, wrist and finger extension, and contralateral neck side-flexion. Note symptom reproduction and range limitations.

Positive Finding

Reproduction of radicular pain, paresthesias, or motor symptoms in the median nerve distribution; reduced range of motion compared to the contralateral side

Sensitivity / Specificity

null / null

Interpretation

Neurodynamic test assessing mechanical irritability of the median nerve. Positive findings suggest neural tension, compression, or irritation. Must be differentiated from joint or muscle limitations.

Straight Leg Raise (SLR) / Lower Limb Tension Test

Procedure

Patient supine; passively elevate the affected leg with knee extended. Note angle at which symptoms appear and whether dorsiflexion increases symptoms (Lasègue's sign variant).

Positive Finding

Reproduction of radicular pain, paresthesias, or neurological symptoms (e.g., in sciatic nerve distribution) before 70° hip flexion; increased symptoms with ankle dorsiflexion or contralateral neck flexion

Sensitivity / Specificity

80%–91% / 26%–45%

Rebain et al., 1994, Spine

Interpretation

High sensitivity for lumbar radiculopathy and sciatic nerve mononeuropathy but low specificity. Positive result suggests neural tension but can occur with hamstring tightness or hip flexor restriction. Helpful in ruling out nerve involvement if negative.

Electromyography (EMG) and Nerve Conduction Studies (NCS)

Procedure

Performed by specialist. NCS measures conduction velocity and amplitude of motor and sensory nerves; EMG assesses muscle electrical activity at rest and during contraction using needle electrodes.

Positive Finding

Slowed nerve conduction velocity, reduced compound muscle action potential (CMAP) amplitude, conduction blocks, prolonged distal latency, denervation potentials (fibrillations, positive sharp waves), or motor unit action potential changes consistent with the suspected nerve distribution

Sensitivity / Specificity

null / null

Interpretation

Gold standard electrodiagnostic test for confirming mononeuropathy, localizing the lesion, and determining severity (demyelination vs. axonal loss). Highly specific for the nerve affected and level of compromise. Essential for definitive diagnosis and prognostication.

Froment's Sign (Adductor Pollicis Function)

Procedure

Patient attempts to adduct thumb while examiner tries to pull a piece of paper held between thumb and index finger. Observe for compensatory thumb IP joint flexion or inability to maintain grip.

Positive Finding

Flexion of the interphalangeal (IP) joint of the thumb or inability to maintain adduction (paper easily withdrawn), indicating weakness of the adductor pollicis muscle

Sensitivity / Specificity

null / null

Interpretation

Tests ulnar nerve motor function (deep branch). Positive sign suggests ulnar nerve compression at the elbow or wrist causing motor deficit. Useful for distinguishing ulnar mononeuropathy from other causes of hand weakness.

⚠ Red Flags

  • •Rapidly progressive neurological deficit suggesting acute nerve compression or trauma requiring urgent decompression
  • •Complete sensory loss or paralysis indicating severe axonal damage
  • •Symptoms following significant trauma or fracture with possible nerve transection
  • •Bilateral mononeuropathies or polyeuropathy suggesting systemic disease (diabetes, vasculitis, infection)
  • •Constitutional symptoms (fever, weight loss, night sweats) suggesting underlying infection or malignancy compressing the nerve
  • •Signs of complex regional pain syndrome with significant edema, skin changes, and vasomotor instability
  • •Progressive weakness with atrophy unresponsive to conservative management over 8-12 weeks

⚡ Yellow Flags

  • •Significant psychological distress, catastrophizing, or fear avoidance limiting engagement with rehabilitation
  • •Prominent anxiety or depression concurrent with symptom onset
  • •Secondary gain or compensation-seeking behavior associated with work-related nerve injury
  • •Poor medication compliance or resistance to activity modification despite clear mechanical trigger
  • •High perceived disability disproportionate to objective neurological findings
  • •Work-related psychosocial stressors or job dissatisfaction in occupational nerve compression syndromes

Osteopathic Techniques

Region

Proximal nerve pathway (cervical spine, brachial plexus, or lumbosacral plexus as appropriate)

Technique

Soft Tissue

Rationale

Releases muscular tension and fascia surrounding nerve roots and plexuses, reducing proximal compression and improving neural mobility; addresses trigger points in muscles that may refer symptoms or contribute to entrapment

Region

Site of nerve entrapment (e.g., carpal tunnel, cubital tunnel, fibular head)

Technique

Soft Tissue

Rationale

Gentle soft tissue mobilization and myofascial release at the entrapment site reduces local inflammation, swelling, and muscular guarding; improves tissue compliance and reduces direct pressure on the nerve

Region

Affected peripheral nerve pathway

Technique

Functional

Rationale

Positions the affected nerve in a shortened or pain-free position to reduce tension and mechanical irritation; facilitates neural gliding and reduces protective muscle splinting

Region

Joints proximal and distal to entrapment site (wrist, elbow, shoulder, or ankle/knee as appropriate)

Technique

Articulation

Rationale

Gentle mobilization restores normal joint mechanics and reduces compensatory tension patterns that may contribute to nerve compression; improves overall segmental mobility

Region

Cervical or lumbosacral spine (depending on nerve origin)

Technique

MET

Rationale

Muscle energy techniques release tension in muscles with myofascial attachments affecting the nerve's proximal path; restores cervical or lumbar segmental mobility to reduce proximal nerve root compression

Region

Tissues surrounding affected nerve

Technique

Lymphatic

Rationale

Enhances lymphatic drainage to reduce local edema and inflammatory mediators compressing the nerve; improves tissue perfusion and nutrient delivery to compromised nerve segments

Add-On Approaches

Chinese Medicine

Acupuncture along the affected meridian pathway and at points distal to the entrapment site (e.g., LI-10 for median nerve, TE-3 for ulnar nerve) to promote qi flow and reduce local stagnation; moxibustion for chronic cases with poor circulation

Chiropractic

Manipulation of proximal joints (cervical spine for upper limb mononeuropathies, lumbar spine or hip for lower limb) to reduce nerve root irritation at the spinal level; wrist or ankle manipulation as appropriate to improve joint mechanics at the entrapment site

Physiotherapy

Nerve gliding exercises to promote axonal sliding and reduce adherence within the nerve sheath; progressive resistance training for muscles distal to compression to prevent atrophy; activity pacing and ergonomic modification to eliminate repetitive mechanical stress on the nerve

Remedial Massage

Deep tissue massage to release muscular tension and fascial restrictions surrounding the nerve pathway; targeted trigger point release in muscles contributing to entrapment; myofascial release techniques to improve tissue extensibility and reduce local compression

Rehabilitation Exercises

Nerve Gliding Exercises for Median Nerve

Range of MotionBeginner

Ulnar Nerve Gliding Sequence

Range of MotionBeginner

Gentle Wrist Extension Stretch (Carpal Tunnel Syndrome)

StretchingBeginner

Upper Limb Nerve Tension Mobilization (Slump Stretch Variant)

StretchingIntermediate

Intrinsic Hand Muscle Activation (Lumbrical Exercises)

StrengtheningBeginner

Progressive Grip Strengthening with Therapy Putty

StrengtheningIntermediate

Forearm Pronation and Supination Strengthening (Radial Nerve)

StrengtheningIntermediate

Ergonomic Posture Training for Workstation

PosturalBeginner

Shoulder and Cervical Postural Correction

PosturalBeginner

Single-Leg Balance Training (for Lower Limb Mononeuropathies)

BalanceIntermediate

Ankle and Foot Mobilization (for Peroneal Nerve Compression)

Range of MotionBeginner

Gentle Walking Program with Proper Footwear

CardiovascularBeginner

Referral Criteria

  • •Rapidly progressive neurological deficit unresponsive to conservative management within 2-4 weeks
  • •Severe weakness or paralysis requiring urgent surgical decompression evaluation by neurologist or orthopedic surgeon
  • •Diagnosis uncertain or atypical presentation requiring electromyography (EMG) and nerve conduction studies (NCS) performed by neurologist
  • •Suspected systemic disease (diabetes, vasculitis, infection) causing mononeuropathy; refer to internal medicine or infectious disease specialist
  • •Failure to improve after 8-12 weeks of conservative management; consider surgical consultation for decompression
  • •Signs of complex regional pain syndrome with disproportionate pain and dysfunction; refer to pain management specialist or physiotherapist specializing in CRPS
  • •Significant psychological distress, anxiety, or depression limiting rehabilitation participation; refer to mental health professional
  • •Suspected malignancy or tumor compressing the nerve; refer for imaging and oncology consultation
  • •Post-traumatic nerve injury with evidence of nerve transection; refer urgently to surgeon for possible nerve repair
  • •Bilateral mononeuropathies or evidence of polyeuropathy; refer to neurologist to investigate underlying systemic cause