Summary & Overview
CPT 64644: Chemical Injection into Five or More Muscles of One Extremity
CPT code 64644 denotes a therapeutic procedure in which a chemical agent (for example, Botox®) is injected into five or more muscles of a single extremity to relieve pain and reduce muscle spasms. This code captures a targeted neuromodulator neurolytic intervention commonly used in spasticity management and pain control for limb-specific conditions. Nationally, the procedure is performed in outpatient procedural settings and has implications for clinical management, utilization monitoring, and payment policy for specialty and rehabilitation providers.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise national overview of billing and clinical context for CPT code 64644, including common sites of service, typical clinical indications implied by the description, and the kinds of benchmarks and policy elements that affect coverage and payment decisions. The publication addresses coding scope, procedural intent, and where stakeholders might focus review — such as documentation of muscle targets and medical necessity — while summarizing typical payer considerations.
This resource outlines what to expect from payer coverage patterns, summarizes relevant benchmarking topics, and provides clinical context to support accurate coding and administrative review. Data not available in the input.
Billing Code Overview
CPT code 64644 describes a procedure in which the provider injects a chemical neurolytic agent, such as Botox®, into five or more muscles of one extremity to relieve a patient's pain and muscle spasms. This service is a targeted therapeutic injection using a neuromodulator or neurotoxin to reduce spasticity and associated pain in a single limb.
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Service type: Therapeutic chemical neurolytic injection to multiple muscles of one extremity
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Typical site of service: Outpatient clinic, ambulatory surgery center, or other outpatient procedural setting where targeted injections are performed
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult with focal spasticity or symptomatic muscle overactivity of one upper or lower extremity following stroke, traumatic brain injury, multiple sclerosis, or cerebral palsy. The patient presents to an outpatient neurology, physiatry, or orthopedic clinic for evaluation of persistent painful muscle spasms and limited function despite oral antispasmodic therapy and physical therapy. After evaluation, the provider discusses chemodenervation with onabotulinumtoxinA (Botox®) targeting five or more muscles in one extremity to reduce spastic hypertonicity and pain and to improve range of motion and ease of caregiving.
The clinical workflow includes an initial history and focused neurologic/musculoskeletal exam, review of prior therapies, informed consent, and documentation of target muscles and estimated units. On the day of service the patient is positioned in an exam or procedure room in an outpatient clinic, ambulatory surgery center, or hospital outpatient department. The provider performs localization by palpation, anatomic landmarks, or adjunctive electromyography (EMG) or ultrasound guidance if clinically indicated, then injects the toxin into five or more muscles of the affected extremity. Post-procedure observation, discharge instructions, and scheduling of follow-up for outcome assessment and potential repeat injections are documented.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
25 | Significant, separately identifiable E/M service on the same day as a procedure |