Jeremy K Cutsforth-Gregory1, J Eric Ahlskog2, Andrew McKeon3, Melinda S Burnett4, Joseph Y Matsumoto5, Anhar Hassan6, James H Bower7. 1. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: cutsforthgregory.jeremy@mayo.edu. 2. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: eahlskog@mayo.edu. 3. Department of Neurology, Mayo Clinic, Rochester, MN, USA; Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA. Electronic address: mckeon.andrew@mayo.edu. 4. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: burnett.melinda@gmail.com. 5. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: jmatsumoto@mayo.edu. 6. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: hassan.anhar@mayo.edu. 7. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: bower.james@mayo.edu.
Abstract
INTRODUCTION: Runner's dystonia has previously been described in small series or case reports as a lower limb, task-specific dystonia. We have occasionally encountered this disorder and recognized the same phenomenon in non-runners regularly engaging in lower limb exercise. We wished to characterize the syndrome further, including outcomes, treatment, and the diagnostic usefulness of electrophysiology. METHODS: We conducted a retrospective review and follow-up survey of adults seen at Mayo Clinic (1996-2015) with task-specific dystonia arising after prolonged repetitive lower limb exercise. The findings were compared to all 21 previously reported cases of runner's dystonia. RESULTS: We identified 20 patients with this condition, 13 runners and seven non-runner athletes. Median age at dystonia onset was in mid-adulthood. Correct diagnosis was delayed by a median of 3.5 years in runners and 1.6 years in non-runners, by which time more than one-third of patients had undergone unsuccessful invasive procedures. Most patients had dystonia onset in the distal lower limb. Dystonia was task-specific with exercise at onset but progressed to affect walking in most. Sensory tricks were reported in some. Surface EMG was consistent with task-specific dystonia in nine patients. Botulinum toxin, levodopa, clonazepam, trihexyphenidyl, and physical therapy provided modest benefit to some, but all patients remained substantially symptomatic at last follow up. CONCLUSIONS: Repetitive exercise dystonia is task-specific, confined to the lower limb and occasionally trunk musculature. It tends to be treatment-refractory and limits ability to exercise. Diagnosis is typically delayed, and unnecessary surgical procedures are common. Surface EMG may aid the diagnosis.
INTRODUCTION:Runner's dystonia has previously been described in small series or case reports as a lower limb, task-specific dystonia. We have occasionally encountered this disorder and recognized the same phenomenon in non-runners regularly engaging in lower limb exercise. We wished to characterize the syndrome further, including outcomes, treatment, and the diagnostic usefulness of electrophysiology. METHODS: We conducted a retrospective review and follow-up survey of adults seen at Mayo Clinic (1996-2015) with task-specific dystonia arising after prolonged repetitive lower limb exercise. The findings were compared to all 21 previously reported cases of runner's dystonia. RESULTS: We identified 20 patients with this condition, 13 runners and seven non-runner athletes. Median age at dystonia onset was in mid-adulthood. Correct diagnosis was delayed by a median of 3.5 years in runners and 1.6 years in non-runners, by which time more than one-third of patients had undergone unsuccessful invasive procedures. Most patients had dystonia onset in the distal lower limb. Dystonia was task-specific with exercise at onset but progressed to affect walking in most. Sensory tricks were reported in some. Surface EMG was consistent with task-specific dystonia in nine patients. Botulinum toxin, levodopa, clonazepam, trihexyphenidyl, and physical therapy provided modest benefit to some, but all patients remained substantially symptomatic at last follow up. CONCLUSIONS:Repetitive exercise dystonia is task-specific, confined to the lower limb and occasionally trunk musculature. It tends to be treatment-refractory and limits ability to exercise. Diagnosis is typically delayed, and unnecessary surgical procedures are common. Surface EMG may aid the diagnosis.
Authors: Omar F Ahmad; Pritha Ghosh; Christopher Stanley; Barbara Karp; Mark Hallett; Codrin Lungu; Katharine Alter Journal: Toxins (Basel) Date: 2018-04-20 Impact factor: 4.546
Authors: Sarah Pirio Richardson; Eckart Altenmüller; Katharine Alter; Ron L Alterman; Robert Chen; Steven Frucht; Shinichi Furuya; Joseph Jankovic; H A Jinnah; Teresa J Kimberley; Codrin Lungu; Joel S Perlmutter; Cecília N Prudente; Mark Hallett Journal: Front Neurol Date: 2017-05-03 Impact factor: 4.003