Carpal tunnel syndrome

Last reviewed: 7 May 2023
Last updated: 19 May 2023

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • numbness of hand(s)
  • nighttime worsening
  • numbness in median nerve distribution
  • numbness confined to palmar aspect of the first 4 fingers
More key diagnostic factors

Other diagnostic factors

  • symptoms are intermittent
  • onset is gradual
  • weakness of hand
  • clumsiness
  • aching and pain in arm
  • weakness of thenar muscles (abductor pollicis brevis, or APB, in particular)
  • normal reflexes
  • finger stiffness
  • cold sensitivity
  • atrophy of thenar eminence
Other diagnostic factors

Risk factors

  • age 40-60 years
  • high BMI
  • female sex
  • fractured wrist/carpal bones
  • square wrist
  • rheumatoid arthritis
  • diabetes
  • pregnancy
  • congenital carpal tunnel stenosis
  • occupational exposure
  • tobacco smoking
  • thyroid disorders
  • significant computer use
More risk factors

Diagnostic investigations

1st investigations to order

  • electromyogram (EMG)
More 1st investigations to order

Investigations to consider

  • ultrasound of the wrist
  • MRI of the wrist
More investigations to consider

Treatment algorithm

ACUTE

clinical diagnosis of carpal tunnel syndrome (CTS) without electromyogram (EMG) confirmation, or pregnant women

mild or moderate based on EMG findings (nonpregnant)

severe based on EMG findings (nonpregnant)

ONGOING

moderate based on EMG findings + failed splint and corticosteroid injection(s)

refractory to surgery

Contributors

Authors

Nigel Ashworth, MBChB, MSc, FRCP(Can)
Nigel Ashworth

Professor

Division of Physical Medicine & Rehabilitation

Faculty of Medicine & Dentistry

University of Alberta

Edmonton

Canada

Disclosures

NA is an author of a number of references cited in this topic.

Peer reviewers

Ines C. Lin , MD, MSEd

Associate Professor of Surgery

Division of Plastic Surgery, Department of Surgery, and Department of Orthopaedic Surgery

Perelman School of Medicine at the University of Pennsylvania

Philadelphia

PA

Disclosures

ICL declares that she has no competing interests.

Peter C. Amadio, MD

Dean for Research Academic Affairs

Lloyd A. and Barbara A. Amundson Professor of Orthopedic Surgery

Professor of Biomedical Engineering

Mayo Clinic

Rochester

​MN

Disclosures

PCA declares that he has no competing interests.

Shawn Marshall, MD, MSc

Associate Professor

University of Ottawa

Ottawa

Ontario

Canada

Disclosures

SM declares that he has been primary author and co-author of Cochrane systematic reviews of nonsurgical interventions for treatment of carpal tunnel syndrome.

Tim J. Doherty, MD, PhD

Associate Professor

The University of Western Ontario

London

Ontario

Canada

Disclosures

TJD declares that he has no competing interests.

Michael Plant, MD, FRCP

Consultant Rheumatologist

The James Cook University Hospital

South Tees Hospitals NHS Foundation Trust

Middlesbrough

UK

Disclosures

MP declares that he has no competing interests.

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