From the Guidelines
Mimics of carpal (carpopedal) spasms include tetany from other causes, seizure disorders, dystonic reactions, peripheral nerve injuries, complex regional pain syndrome, and psychogenic disorders. These conditions can present with similar hand and foot muscle contractions, making diagnosis challenging. Some of these mimics, such as dystonic reactions, can be medication-induced, particularly from antipsychotics or antiemetics like metoclopramide, as noted in the treatment of tardive dystonia 1. Key considerations in distinguishing these mimics from true carpopedal spasms include:
- Evaluation of vital signs
- Medication history
- Laboratory testing for electrolyte abnormalities, particularly calcium, magnesium, and phosphate levels
- Pattern of muscle involvement
- Triggering factors
- Associated symptoms Certain medications can also induce symptoms resembling carpopedal spasms, including lithium toxicity and serotonin syndrome. While true carpopedal spasms are typically associated with hypocalcemia causing neuromuscular hyperexcitability, these mimicking conditions have different underlying mechanisms, such as dopamine receptor blockade in the basal ganglia in dystonic reactions. A thorough clinical assessment is necessary to accurately diagnose and manage these conditions.
From the Research
Mimics of Carpal (Carpopedal) Spasms
The mimics of carpal (carpopedal) spasms can be attributed to various underlying causes, including:
- Dysregulation of electrolytes, such as hypokalemia, hypomagnesemia, or hypocalcemia 2, 3, 4
- Metabolic or endocrine disorders, including hypoparathyroidism 3
- Alkalosis, which can be caused by excessive vomiting or hyperventilation 2, 3, 5
- Dehydration and hypovolemia 4
- Certain medical conditions, such as rhabdomyolysis 4
- Postoperative complications, including tetany despite normal serum calcium levels 6
Clinical Presentations
These underlying causes can manifest as carpopedal spasms, as well as other symptoms, including: