What is the incidence of muscle aches after an intra-articular steroid injection?

Incidence of Muscle Aches After Intra-articular Steroid Injection

Muscle aches or injection-site soreness occur in approximately 13% of patients following intra-articular steroid injections, making it the most common delayed adverse event. 1, 2

Specific Incidence Data

The most robust data comes from a retrospective analysis of 191 sacroiliac joint injections, which provides the clearest picture of post-injection muscle and injection-site symptoms: 2

• Injection-site soreness: 12.9% (17 out of 132 patients with follow-up data) 1, 2
• Pain exacerbations: 5.3% (7 out of 132 patients) 1, 2
• These delayed adverse events typically occurred within 24-72 hours after the procedure 2

Important Clinical Context

Timing of Symptoms

• Injection-site soreness and muscle aches are delayed adverse events, not immediate complications 2
• Symptoms manifest within the first 2-3 days post-injection 2
• Some patients may experience a temporary increase in pain (post-injection flare) during the first 24-48 hours before experiencing improvement 3

Patient-Specific Risk Factors

• Younger patients experience significantly more delayed adverse events including muscle aches (P = 0.0029) 2
• Bilateral procedures are associated with more delayed adverse events compared to unilateral injections (P = 0.024) 2

Other Common Side Effects for Comparison

To put muscle aches in context, the complete adverse event profile includes: 1

• Immediate adverse events:

  • Vasovagal reactions: 2.1-2.5% 1, 2
  • Steroid-clogged needle: 0.5% 1, 2

• Delayed adverse events (within 24-72 hours):

  • Injection-site soreness: 12.9% 2
  • Pain exacerbations: 5.3% 2
  • Facial flushing and/or sweating: 2.3% (steroid-specific effect) 1, 2

Rare but Documented Muscle Complications

While injection-site soreness is common and benign, acute steroid-induced myopathy is an extremely rare complication: 4

• Presents as proximal muscle weakness 4
• Can occur after a single intra-articular injection 4
• Onset typically within 14 days of glucocorticoid exposure 4
• Treatment is supportive with outpatient management 4

Clinical Implications

Patients should be counseled that injection-site soreness affecting approximately 1 in 8 patients is a common, self-limited adverse event that resolves spontaneously. 2 This is distinct from the therapeutic anti-inflammatory effects of corticosteroids, which typically begin within 2-7 days after injection. 3