Carpal tunnel syndrome (CTS) is one of the most common types of entrapment neuropathy in the upper extremity. Entrapment neuropathy is a fancy way of describing nerve compression.
It is mostly seen in middle-aged workers, can contribute towards major dysfunction and time lost time at work, home and with normal lifestyle activities.
Our daily exposure to sitting, working behind a desk and technology are major contributing factors towards developing this condition or those alike.
As active as we may try to be during the day, the amount of time spent in awkward positions outweighs the time that we are moving. Unless you are a full time paid athlete, the majority of us are recreational, competitive or maybe even semi-pro aside from holding a full-time job.
This means as athletes, we are still predisposed to the risks of developing conditions such as carpal tunnel syndrome. This can significantly impact not only our ability to function daily but also our ability to train and compete as athletes.
So, this month’s topic is going to cover carpal tunnel syndrome, how to address it and prevent it from progressing to the point of limiting function.
The carpal bones and the transverse carpal ligament form the carpal tunnel. These structures are the small bones that make up your hand and the ligament that travels across the wrist.
Nine tendons that work to flex your fingers and thumb run through this space as well as your median nerve. The median nerve provides sensory innervation for your thumb, index finger, and middle finger.
It also provides the motor function to muscles that contribute towards flexing your fingers and thumb and for grasp and pinching movements.
The median nerve is the only nerve that runs through the carpal tunnel. Understanding its innervation, presentation, and function helps clinicians differentiate carpal tunnel from other neuropathies.
The symptoms of carpal tunnel will present as:
The sensory symptoms are usually noticed first, with motor symptoms occurring upon further progression of the condition. The continued engagement of aggravating activity and the more time the nerve is under stress, the worse the symptoms present.
The outside portion of the nerve is mostly sensory, and the deeper layers are motor, which is why muscle dysfunction and weakness is noted upon further compression. A visual concept of a compressed nerve would be comparing a regular tire to a flat tire.
Two quick special tests used are the Phalen’s Test (top) and the Tinel’s Sign (bottom) to determine CTS. The wrist position of the Phalen’s test will reproduce symptoms within 30 seconds due to compression of the area. The tapping of the wrist in the Tinel’s sign maneuver will reproduce symptoms due to the aggravation of the area.
Nerve compression issues can occur throughout the body. Most people are familiar with sciatica, which arises from the nerves that originate in the low back and innervate the legs.
The same can occur in the neck, affecting the nerves that innervate the arms, which is referred to as cervical radiculopathy.
Nerve injuries occur in varying severities from simple aggravation to more involved degenerative forms that occur with ALS, autoimmune diseases, trauma such as lacerations of the nerve and spinal cord injuries
Think of nerve compression issues in regards to the following analogy:
If someone smacked you in the face, initially you would become very upset, angry, and experience pain.
Within time, you would calm time, and things would resolve. If someone were to smack you in the face every hour throughout the day, it would become pretty distressing and disruptive towards your normal function and mood right.
Now if someone were to choke you, initially the same response would happen, but if you were unable to relieve the pressure on your throat, you would eventually die. It is the same concept regarding nerves.
Nerves are susceptible and continued aggravation to them throughout the day causes symptoms. Sometimes the nerve isn’t actually “compressed” at the time the symptoms are felt but are rather due to extra aggravation after the initial incident of injury.
If the nerve stays compressed though, it will eventually die, which ultimately is irreversible and referred to as “nerve damage.”
The most common form of nerve damage to occur in CTS presents as weakness in the thumb and visual display of atrophy in what is referred to as the thenar eminence.
This is the bulky mass of tissue on the palm of your hand that comprises the muscles of your thumb.
Atrophy here results in the hand appearing “flat” and is commonly referred to as “ape hand” since one evolutionary difference between humans and apes is the ability to oppose our thumb for pinch and grip techniques.
Notice the smaller, flatter appearance of the thumb in the right hand on the image on top.
Clinicians are faced with many challenges involving neuropathies regarding diagnosis and treatment. The most critical factors are figuring out the proper cause of the symptoms, severity of involvement and then the appropriate treatment.
Sometimes there is more than meets the eye as the body is dynamic and nerve innervation isn’t always so clear-cut.
An example of a differential diagnosis would involve an injury to a branch of the median nerve known as the anterior interosseus nerve (AIN). This nerve innervates muscles that allow you to pinch BUT has no sensory innervation.
When someone is experiencing nerve-like symptoms, noticing reports of only motor dysfunction and no sensory issues can help to determine the diagnosis.
Special tests like the “O.K. sign” are also used to help differentiate AIN involvement from carpal tunnel. When the AIN is involved, the person cannot pinch to form and “O.K.” position.
The “O.K. sign” for AIN involvement. The muscles affected are the ones that flex the tips of the index finger and thumb.
So, once we recognize the symptoms, what do we do?
The problem with carpal tunnel syndrome is that it is a commonly known condition. Your average person has at least heard of it in some form of discussion. When it comes to typical issues, many people have the misconception that since it is common, it’s not as severe, and it will just resolve on its own.
If so, many people have it and are still functioning it must be tolerable, right?
Conventional thought processes tend to associate something that doesn’t kill you within 24 hours isn’t that bad. Just because something is familiar, doesn’t mean it is normal and sometimes the worst conditions have a gradual onset.
Recent research has been investigating more thoroughly the best treatment approaches for CTS.
Studies have been investigating if surgery is the best option. Surgical techniques can consist of an open procedure or endoscopic depending on patient presentation, medical history, surgeon preference, and patient preference.
Many studies have been demonstrating that physical therapy and conservative treatment are less expensive and just as useful for treating mild to moderately involved CTS.
Studies have also been comparing outcomes from other studies in meta-analyses to find the best conclusions considering that CTS can cause dysfunction severe enough to keep individuals out of work for quite some time.
Following surgery, it has been found that individuals do not return to work for around eight weeks. The trade-off of the amount of time spent in therapy and recovery from surgery seems to be comparable in some cases.
Despite having conservative options available, surgical consultation is advised when thenar atrophy is present; symptoms are worse at night, symptoms have not responded to conservative treatment, and signs have been present for a year or greater.
Considering conservative treatment, the best approach is starting with necessary steps such as what is provided in this article, knowledge.
Awareness of the symptoms can contribute to early innervation and prevent symptoms from manifesting to a chronic phase.
Stretching is the first easily accessible technique that can be used.
Stretching of the hands, wrists, and elbows and postural corrections at the shoulder and torso can help to reduce tissue aggravation and stress build-up.
Reducing stress in the soft tissue can eliminate the chances of pressure and nerve involvement.
When symptoms are flared up, stretching sometimes can make things worse. At this point, the rest is appropriate. Resting splints and braces are often issued to wear at night.
When symptoms still aren’t residing, studies have shown good outcomes with extending the time the braces are worn from nighttime to periods throughout the day.
The combination of using a brace and steroid injections is beneficial in the short term, but long-term effects are not always guaranteed from injections.
Injections also have limited effectiveness when symptoms have become chronic.
Ergonomic adjustments and activity modifications are also crucial. Adjusting workstation setups such as keyboard placement, mouse type, pressure points of where the wrists come into contact during typing and mouse use and chair set up can be helpful.
Physical therapists can provide manual techniques such as soft tissue work, joint mobilizations, and corrective exercises to restore proper balance to the cervical and thoracic spine promoting improved posture and body awareness for the individual.
Physical therapy may also consist of treatment referred to as “neurodynamics” and “nerve glides.”
Sometimes when there is a site of injury, the nerve may become stuck in areas of inflamed tissue, scarring or may be limited in its movement due to aggravation. The nerves should be able to glide throughout the body with the muscles, blood vessels, and fascia as you move.
Research has demonstrated mixed outcomes on neurodynamics and the direct impact on CTS.
Sometimes issues at the cervical spine can cause limitations distally into the arm, presenting as radiating symptoms into the hand from limited mobility at the neck.
A presentation like this is not true CTS, but another example of related symptoms and conditions. Regardless, nerve mechanics are always assessed in a proper physical therapy consultation.
This funny looking move is a very common self-mobilization technique done by the patient to help mobilize the nerve tract. More complex moves involving the therapist providing mobilizations and involvement are also applied when appropriate.
About the author
Michael St. George, PT, DPT (@icore_stgeorge on Instagram) is a physical therapist who works for Excel Physical Therapy and Fitness which is a private practice that is based around the greater Philadelphia region and suburbs. He is FMS, SFMA, Y Balance and Motor Control Test Certified with 8 years of experience in outpatient orthopedics and sports medicine. His training consists of experience working with physicians and surgeons from the Rothman Institute and therapists in his field specializing in various manual techniques and advanced treatment procedures.