Nerve compression in the neck, shoulders and wrists from yoga practice

It is quite common for yogis, particularly women, to develop wrist pain and numbness or tingling in the whole hand or individual fingers, either when they are doing arm balances or Chaturanga or at night if they sleep with arms raised above the head although these sensations subside if the arm is placed alongside the body. Such symptoms should be taken very seriously if the numbness becomes constant because nerve compression causes weakness or even paralysis of the muscles in the hands.

Clear-cut medical diagnosis of nerve compression symptoms is often difficult and controversial. Wrist pain is frequently diagnosed as Carpal tunnel syndrome (Median nerve compression); however, nerve compression and pain caused by yoga originates in postural problems and imbalance in the muscles of the arm, neck or shoulders, not just the wrists.

Although it’s commonly taught that good alignment prevents shoulder problems, no amount of perfect alignment can prevent muscle imbalances developing over time if a yoga practice is treated as body conditioning and biased towards poses that strengthen the chest and abdominal muscles, especially if yoga asana practice is the sole form of exercise.

There are a number of different nerves in the arms and the location of the tingling sensations or pain in the fingers or hand will identify which nerve is being compressed. Diagnosis and treatment of crushed nerves is complicated because nerves can be compressed at different or even multiple places in the arms, neck or shoulders – these are sometimes referred to as double or treble crush syndromes.

Surgery is often recommended to free trapped nerves but doesn’t necessarily help because the muscular conditions that created the trapped nerve will remain and be perpetuated by continuing with a yoga practice that caused it in the first place. Muscle release techniques and massage tends to give temporary relief and sometimes makes symptoms worse, for the same reason. Nerve compression can be resolved without surgery by consulting with a Biokineticist who can prescribe appropriate exercises and stretches.

Below are common types of nerve compression that occur in yoga, besides Carpal tunnel syndrome:

Ulnar nerve compression causes tingling or numbness in the last two fingers and outer edge of the hand and is commonly the result of bad posture: Yogis can develop very round shoulders, a forward-tilting pelvis and a forward head position from doing abdominal crunching exercises, particularly those designed to strengthen the Psoas muscle. Tension in the shoulder girdle translates into tension in the arm muscles and elbows, and abnormal pressure on the wrists. The main sites of compression are

• The fascia at the back of the elbow (Cubital tunnel syndrome) can be caused by keeping the elbows in a bent position as in Chaturanga or arm balances. The shortened, tight Bicep that results pulls on the scapula and causes tension in the Triceps and surrounding fascia at the back of the elbow, trapping the nerve
• At the wrists (Guyon’s canal syndrome), from constant pressure of the hands against hard surfaces: when yogis spend too much time on their wrists.

Thoracic outlet syndrome is compression of nerves and blood vessels at the neck, common in people with elevated Scapulae (tight upper Trapezius and Levator Scapulae) and tight neck muscles – especially the Scalenes – and is considered to be a cause of winging shoulder blades. Ashtangis often develop winging shoulder-blades without having nerve compression and need to retrain shoulder function: mainly the Serratus Anterior muscle. Abdominal exercise is also a contributing factor: crunching exercise strengthens the neck in an abnormal forward position, makes the Sternocleidomastoid muscles tight and causes general tension in the muscles of the neck and upper Trapezius.

Stretching the neck in all directions usually relieves thoracic nerve compression, but stretching the front and back of the neck happens in yoga in Halasana (Plough), Matsyasana (Fish) or Salamba Sarvangasana (Shoulderstand). People who can’t perform these poses because of vertebrae-related problems should consult a physiotherapist or similar for alternative stretches. Bear in mind that these poses stretch the front and back of the neck, not the sides. Stretching the neck while seated to the sides at 45 and 90 degree angles is very important for lengthening the Scalenes and Upper Trapezius and should be included in every class.

Coracoid pressure syndrome occurs when the Pectoralis minor muscle that stabilises and anchors the scapula to the chest wall at the front of the body becomes tight, compressing the nerves and blood vessels that travel under the muscle and down the arm affecting circulation and nerve impulses so that the hands are often blue in colour and have tingling sensations. The Pectoralis minor shortens when a person has round shoulders and tight biceps.

• In yoga, shoulder blades will become protracted (forward) as a result of too much abdominal crunch exercise, ‘core’ exercises such as knee-to-nose or elbow in plank position, arm balances and Chaturanga. Although the shoulders aren’t protracted in Chaturanga, bent elbows shorten the biceps, pulling the scapula forward and down.
• Bound poses stretch out the Pectoralis minor and are useful for relieving pressure on the nerves and veins. The focus here should be on sitting tall, lifting the shoulder, pulling the collar-bone back and then pulling the shoulder blade down, rather than somehow trying to grab the hands or fingers behind the back. There is often very little useful guidance or emphasis on binds in many yoga classes and the results can be very damaging. Men and women with tight shoulders struggle to make binds but can usually get into these poses if they are taught this method. People with longer torso and shorter leg body proportions also struggle with seated binds and should rather thread the hand under, instead of around the knee to clasp the opposite hand or wrist instead of rounding their backs to try to make the bind.
  • Binds should be practiced with great care if the shoulder joints are unstable and teachers or adjusters should never pull on the arms to try to force students into these positions

It is possible to have a strong yoga practice without experiencing nerve compression symptoms but this requires careful attention to sequencing: muscle imbalance in the upper body is common in yoga and the Biceps muscles are typically tight and underdeveloped and the Triceps overdeveloped. Healthy shoulders require both pushing and pulling movements and pulling doesn’t take place in a standard yoga class – pushing strengthens chest and Triceps muscles while pulling strengthens biceps and scapular stabilisers – the Rhomboid and lower Trapezius muscles that are essential to good posture. Headstands, handstands and Pincha Mayurasana strengthen these scapular muscles and need to be practiced as much as poses that strengthen the chest. Pulling exercise to strengthen the Biceps is essential to maintaining healthy arms and shoulders with vinyasa-yoga practices, especially Ashtanga.

Popular ‘core exercises’ in plank position and various forms of abdominal crunching may be helpful for beginners but these should be discontinued once a useful level of strength is reached. Core strength is in the poses themselves: for example, Vasistasana and Purvottanasana open the chest and shoulders are good core strengtheners but are usually overlooked in favour of exercise that tightens up the front of the body. The need to crank out repetitions of some variety of abs-exercise represents a workout mentality rather than a yoga practice and has extremely bad effects on body posture and shoulder positioning over time.

Women who aspire to gymnastic prowess should consider appropriate gymnastic training rather than considering a yoga practice suitable conditioning for the upper-body. Men have larger upper-bodies and can achieve the necessary upper body strength for these poses quite easily without as many negative side-effects. Although women can develop very strong upper backs and shoulders, they need to approach upper body strengthening carefully or suffer the consequences.

Reading sources:
Kendall, McCreary, Provance, 1993, Muscles: Testing and Function
Sharkey, 2008, The Concise book of Neuromuscular Therapy