Summary
Definition
History and exam
Key diagnostic factors
- hx of concurrent hemodialysis (organic cause)
- hx of cirrhosis (organic cause)
- pregnancy (idiopathic cramp)
- hx of strenuous exercise (idiopathic cramp)
- hx of medication use (idiopathic cramp)
- nocturnal onset (idiopathic cramp)
- gastrocnemius muscle involvement, with or without foot involvement (idiopathic cramp)
- duration <10 minutes (idiopathic cramp)
- predominantly unilateral (idiopathic cramp)
- precipitation by both trivial movements and by forceful contractions (idiopathic cramp)
- visible or palpable muscular knotting
- good response to passive/active stretching (idiopathic cramp)
- normal neurologic exam (idiopathic cramp)
- normal general physical exam (idiopathic cramp)
- other local muscle involvement (neuromuscular disease cramp)
- widespread muscle cramps (lower motor neuron disease)
- duration >10 minutes (organic cause)
- abnormal neurologic exam (organic cause)
- abnormal musculoskeletal exam (organic cause)
Other diagnostic factors
- signs of a chronic medical condition (organic cause)
Risk factors
- pregnancy
- strenuous exercise
- hemodialysis
- cirrhosis
- imatinib
- beta-blockers with intrinsic sympathomimetic activity
- statins
- age >60 years
- female gender
- FHx of cramp
- other prescribed drugs
- creatine supplementation
- hypoglycemia in diabetes mellitus
- chronic diseases
- home parenteral nutrition
Diagnostic investigations
Investigations to consider
- serum hCG
- fasting serum metabolic panel
- TSH
- HbA1c
- serum LFTs
- PT and INR
- serum myoglobin and urinalysis
- serum CK-MM
- serum alpha-tocopherol (vitamin E)
- serum zinc
- EMG
- nerve conduction studies
- serum aldolase
- muscle biopsy
- genetic studies
Treatment algorithm
Contributors
Authors
Professor of Clinical Neurology
Weill Cornell Medical College
Attending Neurologist
Director, Neuromuscular Service and EMG Laboratory
New York Presbyterian Hospital
New York
NY
Disclosures
MR is an assistant editor for Neurology Alert and a contributor to Merck Manuals.
Dr Michael Rubin would like to gratefully acknowledge Dr Justin Mhoon and Dr David R.P. Guay, previous contributors to this monograph. JM declares that he has no competing interests. DRPG is an author of a reference cited in this monograph.
Peer reviewers
Assistant Professor of Neurology
Department of Neurology
Washington University School of Medicine
St. Louis
MO
Disclosures
TMM is an author of a reference cited in this monograph.
Physician
Department of Neurology
Penn Presbyterian Medical Center
University of Pennsylvania Health System
Philadelphia
PA
Disclosures
SK declares that he has no competing interests.
Professor and Goodfellow Postgraduate Chair
Department of General Practice & Primary Health Care
University of Auckland
Auckland
New Zealand
Disclosures
FG-S declares that she has no competing interests.
Use of this content is subject to our disclaimer