Carpal Tunnel Syndrome (Neurological)

Upper Limb

Overview

Carpal tunnel syndrome (CTS) is a compression neuropathy of the median nerve at the wrist, occurring within the carpal tunnel bounded by the carpal bones and flexor retinaculum. It presents with progressive pain, paresthesia, and weakness in the median nerve distribution, particularly affecting the thumb, index, middle, and radial half of the ring finger. CTS is the most common upper limb entrapment neuropathy and can significantly impact hand function and quality of life.

Pathophysiology

The median nerve becomes compressed within the carpal tunnel due to increased pressure within the confined space. Contributing factors include inflammation of the flexor tendons and synovial sheath, thickening of the flexor retinaculum, swelling from systemic conditions (pregnancy, rheumatoid arthritis, diabetes), or anatomical variations reducing tunnel diameter. Compression impedes axonal transport, causing ischemia and demyelination of nerve fibres, leading to sensory and motor dysfunction. Chronic compression may result in irreversible nerve damage and permanent motor loss.

Typical Presentation

Site

Palmar wrist crease extending distally; thumb, index, middle finger, and radial aspect of ring finger; may radiate proximally to forearm and shoulder

Quality

Tingling, numbness, 'pins and needles' (paresthesia), burning pain, aching in wrist and palm

Intensity

Mild to severe; often progressive; typically worse at night and early morning

Aggravating

Repetitive gripping or pinching activities, typing, driving, sustained wrist flexion, night-time (symptoms often wake patient), Phalen's test position, Tinel's percussion

Relieving

Wrist extension and neutral position, shaking hand vigorously, anti-inflammatory medications, corticosteroid injections, splinting, rest from provocative activities

Associated

Wrist pain and stiffness, hand weakness and clumsiness, difficulty with fine motor tasks (buttoning, writing), thenar muscle atrophy (advanced cases), loss of protective sensation, swelling at wrist

Orthopaedic Tests

Phalen's Test (Wrist Flexion Test)

Procedure

Patient flexes both wrists maximally and holds them together in a prayer position (palms together, wrists flexed) for 60 seconds, or the examiner passively flexes the patient's wrist to maximum flexion and holds for 60 seconds.

Positive Finding

Reproduction or exacerbation of tingling, numbness, or paresthesias in the thumb, index, middle, or radial half of the ring finger within 60 seconds.

Sensitivity / Specificity

68–73% / 67–80%

Hegedus et al., 2018, JOSPT (systematic review and meta-analysis)

Interpretation

Compression of the median nerve within the carpal tunnel. A positive test supports CTS diagnosis; negative test does not rule out CTS given moderate sensitivity.

Tinel's Sign (Percussion Test)

Procedure

Examiner percusses or taps sharply over the median nerve at the wrist, just proximal to the wrist crease (over the carpal tunnel).

Positive Finding

Tingling, electric shock, or paresthesias radiating distally into the distribution of the median nerve (thumb, index, middle, or radial ring finger).

Sensitivity / Specificity

29–61% / 66–87%

Hegedus et al., 2018, JOSPT (systematic review and meta-analysis)

Interpretation

Indicates nerve irritation or compression at the carpal tunnel level. Higher specificity makes it useful for confirmation, but low sensitivity limits its screening utility.

Carpal Compression Test

Procedure

Examiner applies direct pressure with thumbs over the carpal tunnel (between palmaris longus and flexor carpi radialis tendons) for 30 seconds.

Positive Finding

Reproduction of paresthesias or numbness in the median nerve distribution (thumb, index, middle, radial ring finger).

Sensitivity / Specificity

72% / 98%

Hegedus et al., 2018, JOSPT (systematic review and meta-analysis)

Interpretation

Very high specificity makes this test valuable for confirming CTS diagnosis. A positive result strongly suggests median nerve compression.

Semmes-Weinstein Monofilament Test (2-Point Discrimination)

Procedure

Apply calibrated monofilaments of increasing diameter to the fingertips in the median nerve distribution (thumb, index, middle fingers) to establish the threshold of sensory perception.

Positive Finding

Elevated threshold (inability to detect 2–4 g monofilament) or decreased two-point discrimination distance (>6 mm) in median nerve territory compared to ulnar nerve territory.

Sensitivity / Specificity

48–70% / 78–95%

See current literature (standardized sensory testing; no high-quality diagnostic accuracy meta-analysis available)

Interpretation

Objective evidence of sensory nerve dysfunction in CTS. Useful for detecting advanced cases with demyelination; negative result does not exclude mild CTS.

Durkan's Carpal Compression Test (Alternative Compression Protocol)

Procedure

Examiner applies sustained pressure (approximately 30 seconds) directly over the carpal tunnel using both thumbs, maintaining consistent moderate pressure on the median nerve.

Positive Finding

Reproduction of paresthesias or numbness in the thumb, index, middle, or radial ring finger within 30 seconds.

Sensitivity / Specificity

87% / 95%

Kuhlman & Hennessey, 1997, Journal of Hand Surgery; Hegedus et al., 2018, JOSPT

Interpretation

Excellent diagnostic accuracy for CTS when performed with proper pressure and duration. Often superior to Tinel's and Phalen's tests in clinical practice.

Median Nerve Upper Limb Tension Test (ULNT-Median)

Procedure

Patient supine or seated. Shoulder abducted to 90°, externally rotated; elbow extended; forearm supinated; wrist and fingers extended. Cervical spine is contralaterally side-flexed as the final component.

Positive Finding

Reproduction of pain, tingling, or paresthesias in the median nerve distribution; positive result should be compared to the contralateral side.

Sensitivity / Specificity

51% / 86%

See current literature (ULNT reproducibility and sensitivity variable across studies; moderate evidence base)

Interpretation

Tests for mechanosensitivity of the median nerve in the upper limb. May help differentiate CTS from cervical radiculopathy or other upper limb neural patterns.

⚠ Red Flags

  • Progressive neurological deficit with significant motor loss and thenar atrophy indicating advanced nerve damage requiring urgent specialist assessment
  • Acute onset with severe pain, swelling, and systemic symptoms suggesting inflammatory condition (rheumatoid arthritis, systemic lupus erythematosus) requiring medical investigation
  • Bilateral symptoms with constitutional symptoms suggesting systemic disease
  • Symptoms with neck pain and radicular pattern suggesting cervical pathology rather than isolated CTS
  • History of trauma with significant swelling indicating potential compartment syndrome or fracture
  • Rapidly progressive neurological deficit requiring electrodiagnostic confirmation and specialist referral

⚡ Yellow Flags

  • High psychological distress or fear-avoidance behaviours limiting function beyond expected for symptom severity
  • Catastrophic thinking about permanent disability or surgical outcomes
  • Poor coping strategies and limited self-efficacy for symptom management
  • Occupational or recreational activities incompatible with symptom management
  • Secondary gain factors (compensation claims, litigation) affecting treatment motivation
  • Comorbid depression or anxiety disorders impacting rehabilitation engagement
  • Unrealistic expectations regarding treatment timeline or outcomes

Osteopathic Techniques

Region

Wrist and carpal bones

Technique

Articulation

Rationale

Gentle mobilisation of carpal bones (scaphoid, lunate, capitate) restores optimal carpal tunnel dimensions and reduces pressure on the median nerve. Articulation improves synovial fluid distribution and reduces inflammation within the tunnel.

Region

Forearm flexor compartment

Technique

Soft Tissue

Rationale

Direct soft tissue techniques to flexor carpi radialis, palmaris longus, and flexor digitorum superficialis reduce muscular tension and oedema. Myofascial release of hypertonic muscles decreases pressure within the carpal tunnel and improves local circulation.

Region

Wrist and hand

Technique

MET

Rationale

Muscle energy techniques applied to wrist flexors and intrinsic hand muscles restore optimal muscle length-tension relationships. Reciprocal inhibition reduces hypertonicity and normalises force balance across the wrist joint.

Region

Cervical spine and thoracic outlet

Technique

Articulation

Rationale

Upper cervical and thoracic spine mobilisation addresses proximal nerve tension and ensures optimal neural mobility along the entire median nerve pathway. Releases cervical compression that may contribute to double-crush phenomenon.

Region

Flexor retinaculum and carpal ligaments

Technique

Functional

Rationale

Functional technique positions tissues in shortened state to reduce stretch on compressed nerve. This technique reduces mechanical stress on the median nerve during healing phases and improves proprioceptive awareness of optimal wrist positioning.

Region

Upper limb and thoracic region

Technique

Lymphatic

Rationale

Lymphatic drainage techniques reduce inflammation and oedema within the carpal tunnel and forearm. Enhanced lymphatic clearance decreases pressure and creates space for nerve recovery, particularly beneficial in inflammatory presentations.

Add-On Approaches

Chinese Medicine

Acupuncture to PC7 (Daling), PC8 (Laogong), HE3 (Shaohai), and LI5 (Yangxi) can reduce inflammation and pain. Moxibustion may improve circulation. TCM diagnosis often involves Qi stagnation and Blood stasis in the Pericardium and Heart meridians; herbal formulas supporting Qi movement (e.g., Xiao Yao San variations) may be beneficial alongside manual treatment.

Chiropractic

Carpal bone adjustments using specific chiropractic techniques to restore proper carpal arch alignment. Cervical spine manipulation to address upper cervical dysfunction and reduce proximal nerve compression. Wrist manipulation to optimise joint mechanics and reduce tunnel pressure.

Physiotherapy

Progressive nerve gliding exercises to improve median nerve mobility through the tunnel. Strengthening of forearm stabilisers and intrinsic hand muscles. Postural re-education to reduce upper crossed syndrome. Graded functional activity progression. Electrotherapies (interferential, TENS) for pain modulation and inflammation reduction.

Remedial Massage

Deep tissue massage to forearm flexor group, particularly flexor carpi radialis and palmaris longus, to reduce muscular tension and localised inflammation. Trigger point release in hypertonic muscle regions. Transverse friction massage to carpal ligaments. Soft tissue mobilisation of the wrist and hand complex to improve tissue extensibility.

Rehabilitation Exercises

Wrist flexion and extension

Range of MotionBeginner

Wrist radial and ulnar deviation

Range of MotionBeginner

Median nerve gliding stretch - fist closure progression

StretchingBeginner

Forearm flexor stretch - supinated arm with wrist extension

StretchingBeginner

Nerve gliding - full median nerve mobilisation sequence

StretchingIntermediate

Intrinsic hand muscle strengthening - finger abduction and opposition with resistance band

StrengtheningIntermediate

Forearm pronation and supination with light resistance

StrengtheningIntermediate

Wrist stabiliser strengthening - isometric holds in neutral

StrengtheningBeginner

Cervical retraction and shoulder blade squeeze - addressing upper crossed syndrome

PosturalIntermediate

Ergonomic workstation adjustment and neutral wrist posture training

PosturalBeginner

Upper limb gentle mobilisation routine - arm circles and swinging movements

CardiovascularBeginner

Fine motor coordination - pinch and grip progressions with varied object sizes

BalanceIntermediate

Referral Criteria

  • Failure to improve with conservative management over 6-12 weeks despite compliance with treatment and activity modification
  • Progressive neurological deficit including significant motor weakness, thenar muscle atrophy, or loss of protective sensation
  • Severe night symptoms unresponsive to night splinting affecting sleep quality and function
  • Confirmed CTS on electrodiagnostic testing (EMG/NCS) with moderate to severe slowing of nerve conduction velocity
  • Patient desire for surgical consultation despite adequate conservative trial (carpal tunnel release surgery may be indicated)
  • Acute onset with severe symptoms suggesting inflammatory pathology (rheumatoid arthritis, systemic lupus erythematosus) requiring rheumatology assessment
  • Bilateral CTS with systemic symptoms suggesting underlying metabolic or systemic disease requiring medical investigation
  • CTS secondary to identifiable structural cause (wrist fracture, ganglion cyst, tenosynovitis) requiring specialist imaging and management
  • Pregnancy-related CTS that persists beyond 6-8 weeks post-delivery suggesting alternative diagnosis
  • Symptoms inconsistent with median nerve distribution or clinical presentation inconsistent with CTS diagnosis