Cyclist Palsy

By Dr Conor O’Brien


Cyclist Palsy Poster

Cyclist Palsy With CTS

  • Cycling participation has increased dramatically during the pandemic
  • 5% increase in Bike sales
  • Not fatal, but associated with significant injury and accidents
  • Elite cyclist bilaterally
  • Recreational cyclist on cousins bike for weight loss

Cyclist Palsy

Bilateral Cyclist Palsy

INTRODUCTION: Carpal tunnel syndrome (CTS) and Guyon’s Canal syndrome (GCS) are common focal neuropathies. A combination of the 2 has been reported in competitive cycling. We report a case of acute bilateral CTS and GCS caused by aberrant cycling hand positioning which was maintained over a 2-day bike race.

CASE REPORT: A cyclist presented with an 8-week history of bilateral sensory alteration and weakness of all fingers of both hands, following a 500km 2-day cycle race. Windy climatic conditions and an uphill course forced him to cycle with the wrists in a forced flexed position on day 1. On the return journey, he cycled with the plantar surface of wrists on the handlebars. Nerve conduction studies confirmed bilateral CTS and bilateral GCS. Successful non-surgical treatment included injection therapy and wrist splinting. Prevention of neuropathies in subsequent bike races was achieved by wearing gel cycling gloves. The acute bilateral CTS occurred as a consequence of the forced flexed position over 250km on day 1 of the race, and the acute bilateral GCS occurred as a result of placing the volar aspect of the wrists on the handlebars on day 2.

Median Neuropathy

Median Neuropathy

Distal Ulnar Neuropathy At Guyon’s Canal

Distal Ulnar Neuropathy at Guyon's Canal

Neurophysiology And MRI Findings

  • Nerve conduction studies confirmed bilateral CTS and bilateral Guyon’s canal syndrome.
  • With the slowing of the ulnar motor nerves conduction study to the 1st DI muscles, and de-nervation in the distal ulnar innervated 1st DI and ADM muscles.
  • The ulnar sensory nerves may or may not be affected depending on the affected “zone” of the Guyon‘s Canal complex.
  • Slowing in the median motor, sensory and trans-palmar studies.
  • MRI scan no evidence of any nerve hypertrophy or ganglion cyst formation.
  • Sports injuries account for 16% of primary care and A/E consultations.
  • Overuse injuries account for 85%  of all sports injuries.
  • These overuse neuropathies are due to the extrinsic factors of the activity, including bicycle fit and cycling technique. Like many overuse injuries treatment does not necessarily require surgical intervention.
  • Overuse injury is now categorised in medical subject headings as “cumulative trauma disorder (CTD)”.
  • These acute neuropathies respond to conservative treatment which includes injections at the site of entrapment. The prophylactic use of gloves and avoidance of the provoking activity prevented recurrence.
  • Nerve injuries account for 7% of all sports injuries
  • Cyclist Palsy is an overuse sports-related neuropathy
  • Guyon’s canal syndrome and CTS either singularly or in combination have been referred to as cyclist’s palsy.
  • Long-distance cycling can cause a physiological change in the deep branch of the ulnar nerve from the trauma of handlebars.
  • CTS is associated with an increased incidence of Guyon`s Syndrome.
  • Intrinsic and extrinsic factors are causative in Overuse syndromes (Slocum and James 1968)- this case is no different!
  • Alteration in the biomechanics of the bike and the wearing of a protective garment, are the cornerstone to treatment.
  • Research has indicated that up to 24% of cyclists experienced a combination of motor and sensory symptoms in either the median or ulnar nerve distribution (Patterson et al 2003).
  • Long-distance cycling promotes physiologic changes in the deep branch of the ulnar nerve and exacerbates symptoms of carpal tunnel syndrome (Akuthora et al 2005).
  • The occurrence of CTS and Guyon’s syndrome in both hands in a long-distance cyclist was reported at AANEM by Dr Conor O’Brien in 2014 when it appeared for the first time in the literature.

Click here to download the full PDF document for Cyclists Palsy, Clinical Presentation and Electrodiagnostic Evaluation during the Covid Pandemic, by Dr Conor O’Brien.


  1. Slocum DB, James SL. Biomechanics of running. JAMA1968;205:721–8.
  2. M M. Patterson,M M. Jaggars M I. Boyer *Ulnar and Median Nerve Palsy in Long-distance Cyclists A Prospective Study,Am J Sports Med 2003
  3. V Akuthota, ;C Plastaras ; KiLindberg The Effect of Long-Distance Bicycling on Ulnar and Median Nerves: An Electrophysiologic Evaluation of Cyclist Palsy Am J Sports Med August 1, 2005, 33 1224-1230
  4. O’Brien C. Cyclist Palsy, a case of bilateral CTS and Guyon’s canal syndrome in a long-distance cyclist