Referred to as handlebar palsy in the cycling community, Guyon’s canal syndrome (GCS) is an irritation of the ulnar nerve within the palm of the hand. Because compression from outside of Guyon’s canal is responsible for the offending symptoms, the practicing massage therapist must understand the involved anatomy and pathology in order to avoid exacerbating the client’s discomfort.
The Ulnar Nerve
The ulnar nerve’s primary role is to supply sensation to the little finger and lateral half of the ring finger. Additionally, it controls most of the little muscles in the hand that control fine movements as well as some of the forearm muscles responsible for creating a strong grip. Important for grasping objects, the adductor pollicis is often affected by ulnar nerve compression. Therefore, ulnar nerve problems not only cause little and ring finger tingling, but can also manifest as difficulty in holding objects in the hand, or clumsiness when performing precision activities such as writing.
In the wrist, Guyon’s canal is the tunnel formed by the pisiform and hamate bones and the flexor retinaculum ligament. Passing through this tunnel, the ulnar nerve is vulnerable to compressive forces on these structures. However, when evaluating symptoms of ulnar nerve compression, a practitioner must decipher the location of the suspected problem.
Causing similar types of symptoms, there are three primary areas where the ulnar nerve can be compressed:
- he Wrist – which is likely due to compression in Guyon’s canal
- The Elbow – which is likely due to compression in the cubital tunnel
- The Neck – which is likely due to thoracic outlet syndrome or cervical radiculopathy
Because the orientation of the ulnar nerve is unique in all three of these locations, massage approaches will differ for each area.
Marked by numbness and tingling in the ring and small fingers, GCS typically begins with the feeling of pins and needles. If this irritation persists, it is often followed by decreased sensation in the lateral part of the hand. When the small muscles of the hand become affected, weakness and clumsiness eventually result.
There are many causes of GCS, including trauma, fractures and small, benign tumors of the nerve or surrounding tissues of the tunnel. In addition to these structural problems, prolonged pressure on the wrist can cause this syndrome.
Guyon’s canal syndrome may occur as either an acute or chronic compression neuropathy. Acute injuries to Guyon’s canal occur most often when there is an abrupt force on the base of the hand while the wrist is in hyperextension. Falling on an outstretched hand is a good example. Chronic compression injuries occur from pressure maintained on the base of the hand for long periods. A common example is long-distance cycling, where the weight of the body is resting on the handlebars with the wrist in hyperextension.
GCS Distinguishing Pathology
Understanding the mechanics of nerve compression within Guyon’s canal can help a healthcare practitioner administer the most beneficial treatment. Since many people assume they have carpal tunnel syndrome with neurological symptoms in their hand worsening with wrist pressure, isolating the sensory symptoms of ulnar nerve distribution is important for an accurate assessment of GCS.
Because there are no tendons in Guyon’s canal to press on the nerve, pathological compression in GCS occurs from extrinsic factors. Extrinsic nerve compression happens when there is excessive force applied from outside the canal as opposed to pressure originating from inside the canal. In contrast, a condition like carpal tunnel syndrome involves intrinsic pressure because it comes from within the tunnel due to tendon swelling.
Massage for GCS
Once the appropriate tests reveal GCS, deliberately applied massage therapy offers sufferers an alternative to splinting and orthopedic surgery. Because GCS results from external forces causing compression on the ulnar nerve in the tunnel, massage strategies must focus on liberating the compressive force. While massage performed directly over the tunnel may worsen GCS symptoms and impair the healing process, techniques designed to decompress the nerve often provide much sought relief.
According to Doug Alexander, instructor of the Institute’s Nerve Mobilization continuing education course, there are various ways to decompress the ulnar nerve in Guyon’s canal. In this distance-learning course, Alexander gives specific instruction on some of these techniques, including:
- wrist pumping to reduce irritability of the ulnar nerve in the Guyon canal
- fascial release of the Guyon canal
- neural milking proximal to the Guyon canal
- ulnar nerve glides with respect to the Guyon canal
- ulnar nerve stretching in the Guyon Canal
While nerve decompression is extremely valuable to someone struggling with GCS, Alexander cautions practitioners, “You should not be creating any nerve compression symptoms during this process. If nerve symptoms are unavoidable, they should abate within a second or two of the completion of the manipulation. If they continue longer than that, you will need to explore less challenging manipulations until the nerve becomes less irritable.”
While generalized massage strokes aiming at tissue compression can benefit many neurological symptoms, Guyon’s canal syndrome is an exception. By combining detailed study of the wrist’s anatomy and pathology with ulnar nerve decompression techniques, a massage therapist can feel confident in approaching compression within Guyon’s canal.