What is Carpal tunnel syndrome?
Carpal Tunnel Syndrome (CTS) is mechanical compression of the median nerve within the carpal tunnel. Mechanical compression is when a nerve is entrapped by a muscle or ligament.
The median nerve originates in the forearm and travels through the carpal tunnel to innervate the palm, more specifically the first three fingers (thumb, index, and middle fingers).
This compression can cause restriction of blood flow to the forearm and hand. Compression will also result in sensory and/or motor defects in the areas innovated by the median nerve. This can make grip strength and movement of the wrist and fingers difficult. You may find yourself dropping things more or unable to hold onto things.
Carpal tunnel syndrome is the most common nerve entrapment. CTS usually affects adults between the ages of 45-60. Carpal tunnel syndrome is more common in the dominant hand. Those working on an assembly line are at a high risk for developing CTS. There has been a link in the relationship between manual work stress and symptoms.
Prolonged wrist flexion or extension, repetitive wrist movements, increased hours on your smartphone, and exposure to vibrations or the cold are factors contributing to CTS.
Some intrinsic factors include diabetes, hypothyroidism, rheumatoid arthritis, alcoholism, increased BMI, vitamin D deficiency, renal disease, a thickened transverse ligament, and short stature. Prior trauma such as a fracture, dislocation, or osteoarthritis may cause a narrowing of the canal. Fluid retention during pregnancy is a cause of some short-term CTS symptoms.
Patients with carpal tunnel syndrome have a difficulty localizing the pain and may complain that their whole hand is feeling numb. Pain is usually centered over the carpal tunnel while paresthesia (tingling feeling) is generally felt in the thumb, index finger, and middle finger. Pain can sometimes extend through the elbow. Patients may say “shaking out the hands” may relieve symptoms.
CTS compressive symptoms progressively increase between 8pm to 8am due to sleep position overnight. However, symptoms can progress from daytime activity that provokes CTS.
Patients can tell if they have CTS if gripping activities aggravate symptoms. You may experience dropping things or not being able to grip items. Complaints of tight or swollen feeling, skin color changes, and change in hand temperature are usually reported. Patients may reveal tenderness when someone touches the carpal tunnel. Wrist range of motion may be slightly limited and end range of flexion or extension may reduce complaints. You may also notice limited thumb abduction. Patients may experience joint restrictions in the cervical spine or wrist.
An MRI is the primary imaging used to identify cervical radiculopathy or soft tissue pathology of the wrist. However, diagnostic ultrasonography is useful for determining if there is an enlargement or fluid within the median nerve. An EMG/NCS is considered the diagnostic gold standard for identifying and objectively classifying the severity of CTS. If left untreated, carpal tunnel syndrome may result in permanent neurological damage. Clinicians can evaluate strength or muscle weakness with a pinch grip or a palmar grip.
It is highly recommended to make use of conservative management before considering surgical alternatives. There are several clinical trials that demonstrate conservative manual therapy works with carpal tunnel syndrome. Conservative management of CTS should focus on resolving neurologic issues along the entire length of the median nerve.
Myofascial release of the forearm, wrist, and hand is also recommended for CTS. Manipulation and mobilization of the cervical spine and carpal (bones within the hand) bones have shown to benefit those with CTS.
Incorporating cupping has shown to reduce pain and sensory complaints. The addition of kinesiotape has improved CTS outcomes. Some studies support acupuncture to treat CTS. Therapeutic and home stretches should target the cervical spine, scalene muscle, pectoralis muscles, pronator muscles, and wrist flexor muscles.
Some home exercises include chin retractions, median nerve glides, and median nerve floss. Neurodynamic techniques such as median nerve flossing have shown effectiveness with treating some major complaints of CTS and lead to long-term improvements in pain and strength. Patients should be instructed to avoid repetitive wrist flexion or extension. CTS patients are susceptible to a non-neutral wrist position.
Splints that hold the wrist in a neutral or slightly extended position may reduce symptoms, especially those overnight symptoms. Neutral wrist splints are recommended to be worn for at least 6 weeks.