Carpal Tunnel Syndrome (CTS) is a disordered related to nerve compression at the wrist and is the most common form of compressive neuropathy, affecting about 8% of Americans, regardless of occupation. Prevalence is nearly twice that for women compared to men and is more common with increasing age, particularly over 50 years old. Although the exact pathophysiology is unknown, recently literature has been shedding more light on causes and effective treatments for management which has led the American Physical Therapy Association (APTA) to release the first edition of Clinical Practice Guidelines for clinicians and doctors.
The carpal tunnel is an area in the wrist that is formed by the eight carpal bones of the wrist and the transverse ligament which spans over them like a bridge. This rigid tunnel is home to nine flexor tendons which allow for movement of the fingers, two bursa to provide cushioning, and the median nerve which provides sensation and innervation to a portion of skin and musculature of the hand. As the median nerve passes through the tunnel, just under the transverse ligament, it is vulnerable to compression from internal and external forces. Classic symptoms of CTS include numbness or tingling in the thumb, index, and middle fingers and in more severe cases, loss of strength to the muscles of the thumb and fingers. Initial symptoms onset typically occurs at night, but as symptoms worsen individuals may complain of clumsiness or difficulty with gripping and pinching through the day as well. Repeated and forceful hand exertion is the strongest known occupational risk factor with low associations shown with high psychologically demanding jobs, vibration and prolonged non-neutral positioning. Computer users have not been shown to have an increased risk of CTS when compared to the general public or industrial workers.
A number of factors have been implicated in the development of CTS, including elevated carpal tunnel pressure, decreased blood flow to the nerve resulting in ischemia, or compression by surrounding structures. Studies comparing inner carpal tunnel pressure in those about to undergo corrective surgery have found pressure can be up to seven times greater pre-operatively when compared to post-operative measurements. Though maximum tunnel pressure was not different between patients with moderate, severe, or extreme cases, suggesting additional factors may be at play. Both human and animal studies have show pressure can also occur within the nerve itself due to a gradual decrease in intramural blood flow. This lack of blood supply results in fluid and edema retention in and around the nerve, and in severe cases can result in scar formation. Lastly, some have speculated enlargement of the flexor tendons in a condition called tenosynovitis can also be implicated as a case.
A variety of studies have looked to compare the effectiveness of physical therapy to surgical outcomes in patients with CTS. Many have concluded that after one year, patients who have had physical therapy focused on treating the wrist and neck have similar outcomes to those patients who have opted for surgery. Furthermore, the physical therapy patients experienced faster improvements at 1 month compared to surgery as well. These findings demonstrate evidence that patients should consider conservative management with physical therapy prior to considering surgical options. If you have been diagnosed with carpal tunnel syndrome or feel like you this may be you, our therapists at Blue Hills Sports and Spine Rehabilitation can offer strong evidence-based treatment options, as outlined by the APTA’s Clinical Practice Guidelines, to help you recover. Why let pain win? Try PT first. Schedule an appointment today.