Anatomy Organs Home Office Ergonomics Guide Home Office Ergonomics Guide Overview Your Back Back Pain Exercises Anatomy General Tips Products Holistic Help Your Neck Neck Pain Exercises Anatomy General Tips Products Holistic Help Your Eyes Eye Strain Exercises Anatomy General Tips Products Your Shoulders Shoulder Pain Exercises Anatomy General Tips Products Your Wrists Wrist Pain Exercises Anatomy General Tips Products Your Hands Hand Pain Exercises Anatomy General Tips Products Your Hips Hip Pain Exercises Anatomy General Tips Products Your Knees Knee Pain Exercises Anatomy General Tips Products The Anatomy of the Carpal Tunnel A common cause of wrist and hand pain By Brett Sears, PT Brett Sears, PT Facebook LinkedIn Twitter Brett Sears, PT, MDT, is a physical therapist with over 20 years of experience in orthopedic and hospital-based therapy. Learn about our editorial process Updated on August 08, 2022 Medically reviewed by Michael Menna, DO Medically reviewed by Michael Menna, DO Michael Menna, DO, is a board-certified, active attending emergency medicine physician at White Plains Hospital in White Plains, New York. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Anatomy Function Associated Conditions Rehabilitation Next in Home Office Ergonomics Guide Prevention of Carpal Tunnel Syndrome The carpal tunnel is an anatomical structure in your wrist and hand that protects the median nerve and several tendons. It is often the source of a common repetitive strain injury called carpal tunnel syndrome (CTS). The bones, ligaments, and structures around your wrist and hand form an anatomical tunnel. Injury here may cause pain, tingling, and weakness in your wrist and hand and may limit functional use of your upper extremity. Anatomy The anatomical borders of the carpal tunnel are the carpal (wrist) bones and the flexor retinaculum, also known as the transverse carpal ligament. The concave carpal bones—there are eight of them—form the base of the carpal tunnel. These bones are called: ScaphoidLunateTriquetrumPisiformTrapeziumTrapezoidCapitateHamate Atop these bones is the transverse ligament, spanning from the scaphoid and trapezium on the thumb side to the hamate and pisiform on the pinky side of your wrist. The fibers of the transverse carpal ligament run across your wrist joint at the base of your hand. Researchers have found significant variation in thickness of the transverse carpal ligament between individuals. This may account for why some people suffer from carpal tunnel syndrome, while others, exposed to similar repetitive strain, do not experience symptoms. Three small muscles originate from the transverse carpal ligament as well. These are: Abductor pollicis brevisFlexor pollicis brevisFlexor digiti minimi These small muscles move your thumb and pinky finger in each hand and form the natural contours of the palm of your hand. Function The function of the carpal tunnel is to provide an anatomical tunnel and protection for various structures that pass from your forearm and into your hand. There are nine tendons (tendons connect muscles to bones) and a nerve that travel through the passageway formed by the carpal tunnel. The tendons that travel through the carpal tunnel are: Flexor pollicis longusFour tendons of flexor digitorum superficialisFour tendons of flexor digitorum profundus The tendon of the flexor pollicis longus is contained within its own synovial sheath as it passes through the carpal tunnel. The eight flexor digitorum tendons are all contained within one synovial sheath. A synovial sheath is a casing around a tendon that contains synovial fluid, a natural lubricant. This allows the tendons to slide and glide freely as they pass through the carpal tunnel. Some people also classify the flexor carpii radialis tendon as one that passes through the carpal tunnel. This tendon passes through the bands of the bands of the flexor retinaculum instead of through the actual carpal tunnel itself. One of the most important functions of the carpal tunnel is to protect and provide a passageway for the median nerve. The median nerve arises from your neck from cervical level six through thoracic level one. It then courses down your arm and into your hand via the carpal tunnel. Once the median nerve crosses through the carpal tunnel, it divides into two distinct branches called the recurrent branch and the palmar digital nerves. The recurrent branch of the median nerve innervates the muscles around your thumb in an area also called the thenar branch. The palmar digital nerves provides sensory information from your thumb, index, and middle finger. It also innervates small muscles in your first and second finger called lumbricals. Associated Conditions Verywell The most common condition associated with the carpal tunnel is called carpal tunnel syndrome (CTS). This problem affects approximately eight million people each year. Symptoms of carpal tunnel syndrome include: Wrist painPain in the palm of your hand near your thumbPain in your thumb, first, and second fingersTingling in your thumb and first two fingersWeakness in your handLoss of muscle bulk in your thumb (an area called the thenar eminence) Symptoms of carpal tunnel may come on gradually and range from mild to severe. Carpal tunnel syndrome is classified as a repetitive strain injury (RSI), meaning that it occurs as a result of repeated stress to your wrist and hand joints. Carpal Tunnel Symptoms Carpal tunnel syndrome occurs when the transverse ligaments thicken, or by inflammation or swelling in any tissues in the tunnel. This happens when you repeatedly place stress and strain on the front of your wrist. As the ligament is repeatedly injured, your body's repair systems attempt to heal it; cells that make collagen are brought to the area, and the ligament becomes thicker. Thickening of the transverse carpal ligament causes a decrease in space in the carpal tunnel, and the median nerve and tendons there can become pinched, leading to pain, limited mobility, tingling, and weakness in the hand. Other conditions may affect the carpal tunnel and lead to pain or loss of hand and wrist function. These may include: A Colles' fracture of the wrist A Smith's fracture of the wrist Arthritis of the wrist Causes and Risk Factors of Carpal Tunnel Syndrome Rehabilitation There are several treatments available to rehab an injury to your carpal tunnel. These range from conservative to invasive. If you suspect you have carpal tunnel syndrome, you should visit your healthcare provider to get an accurate diagnosis and to start on the right treatment for you. Diagnosis of carpal tunnel syndrome is done by clinical examination and by a test called an electromyographical (EMG) test. Your healthcare provider may gently tap your wrist near the carpal tunnel. If your median nerve is irritated, pain or tingling may occur, indicating possible CTS. An EMG test involves using small needles placed near the median nerve and measuring the speed of an electrical signal that is sent down the nerve. Slowing of the signal as it crosses the carpal tunnel is also a sign of CTS. How Carpal Tunnel Syndrome Is Diagnosed Treatment for carpal tunnel syndrome may range from conservative to more invasive. Exercise for CTS Your healthcare provider or physical therapist may recommend exercises for managing carpal tunnel syndrome. Exercises may include: Tendon gliding exercises Median nerve glides Wrist muscle stretching Wrist and hand strengthening exercises Massage Techniques for Carpal Tunnel Syndrome Splinting People with carpal tunnel syndrome may benefit from using a wrist cock-up splint. This splint, worn at night while sleeping, keeps your wrist and hand in a neutral position, taking pressure off the tendons and median nerve in the carpal tunnel. Injections Your healthcare provider may recommend an injection for your CTS. Injection of a strong anti-inflammatory corticosteroid may be used to decrease pain, decrease swelling to tissues in the carpal tunnel, and improve overall wrist mobility. Surgery Surgery for CTS involves making a small incision in the palm of your hand near your wrist. Your surgeon will then cut away the thickened transverse ligament, taking pressure off the pinched median nerve and its neighboring tendons. After surgery, the palm of your hand will be sutured and you may be required to wear a protective brace for a few weeks. You can expect to slowly increase wrist and range of motion and strength. Most patients return to full function about eight weeks after surgery. It is recommended that you try the most conservative treatments, like exercise and splinting, first if you have CTS. Most cases can be managed effectively, with return to normal pain-free activity in six to eight weeks. If your symptoms are severe and do not remit with conservative treatment, then considering invasive treatments like injections or surgery may be warranted. Prevention of Carpal Tunnel Syndrome 9 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Presazzi A, Bortolotto C, Zacchino M, Madonia L, Draghi F. Carpal tunnel: Normal anatomy, anatomical variants and ultrasound technique. J Ultrasound. 2011;14(1):40-6. doi:10.1016/j.jus.2011.01.006 Goitz RJ, Fowler JR, Li ZM. The transverse carpal ligament: anatomy and clinical implications. J Wrist Surg. 2014;3(4):233-4. doi:10.1055/s-0034-1394150 Cleveland Clinic. Carpal tunnel syndrome. Aboonq MS. Pathophysiology of carpal tunnel syndrome. Neurosciences (Riyadh). 2015;20(1):4–9. Cleveland Clinic. Carpal tunnel syndrome: Diagnosis and tests. Page MJ, O'connor D, Pitt V, Massy-Westropp N. Exercise and mobilisation interventions for carpal tunnel syndrome. Cochrane Database Syst Rev. 2012;(6):CD009899. doi:10.1002/14651858.CD009899 Newington L, Harris EC, Walker-Bone K. Carpal tunnel syndrome and work. Best Pract Res Clin Rheumatol. 2015;29(3):440–453. doi:10.1016/j.berh.2015.04.026 Wright AR, Atkinson RE. Carpal tunnel syndrome: An update for the primary care physician. Hawaii J Health Soc Welf. 2019;78(11 Suppl 2):6–10. Cleveland Clinic. Carpal tunnel syndrome: Management and treatment. By Brett Sears, PT Brett Sears, PT, MDT, is a physical therapist with over 20 years of experience in orthopedic and hospital-based therapy. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit