Muscle Relaxants Have No Role in Costochondritis Management
Muscle relaxants such as cyclobenzaprine should not be used for costochondritis because they are ineffective for this condition—their mechanism targets central nervous system-mediated muscle spasm, not the costochondral inflammation that defines costochondritis. 1
Why Muscle Relaxants Don't Work for Costochondritis
Mechanism Mismatch
- Cyclobenzaprine "relieves skeletal muscle spasm of local origin without interfering with muscle function" and "acts primarily within the central nervous system at brain stem as opposed to spinal cord levels" 1
- Costochondritis is an inflammatory condition of the costochondral or costosternal junctions, not a muscle spasm disorder 2, 3
- The FDA label explicitly states cyclobenzaprine is "ineffective in muscle spasm due to central nervous system disease," and costochondritis involves cartilage inflammation, not muscle pathology 1
Evidence Against Muscle Relaxants for Musculoskeletal Pain
- Although muscle relaxants may relieve skeletal muscle pain, "their effects are nonspecific and not related to muscle relaxation" 4
- Guidelines emphasize that muscle relaxants "should not be prescribed in the mistaken belief that they relieve muscle spasm" 4
- For older persons specifically, "many of these drugs may be associated with greater risk for falls" 4
What Actually Works for Costochondritis
First-Line Treatment: NSAIDs
- NSAIDs are the appropriate first-line pharmacologic treatment for costochondritis as an inflammatory condition 2, 5
- Stretching exercises showed progressive significant improvement compared to control groups (p<0.001) in patients with costochondritis 5
Physical Therapy Approach
- An impairment-based examination and treatment approach including manual therapy and therapeutic exercise directed at the cervicothoracic spine and ribcage showed clinically meaningful changes 3
- Patients treated with this approach (mean 4.8 visits) showed mean pain reduction of 5.1 points on NPRS and were able to return to previous activities without restrictions 3
Refractory Cases
- For severe costochondritis unresponsive to NSAIDs, colchicine has been successfully used, particularly in post-COVID-19 costochondritis cases 6
- Local injection of anesthetic or steroid can be considered, though effectiveness may be limited 5
Common Pitfall to Avoid
The critical error is prescribing muscle relaxants based on the word "muscle" in musculoskeletal chest pain. Costochondritis involves cartilage inflammation at rib-sternum junctions, not muscle spasm requiring central nervous system modulation. This misunderstanding leads to ineffective treatment, delayed appropriate therapy, and unnecessary medication side effects including sedation and fall risk 4, 1.