What is the initial management for a patient presenting with left sternocleidomastoid (muscle in the neck) pain?

Initial Management of Left Sternocleidomastoid Pain

For a patient presenting with isolated left sternocleidomastoid pain without red flag symptoms, begin with conservative management including NSAIDs, muscle relaxants if needed, and physical therapy—imaging is not indicated initially unless red flags are present or symptoms persist beyond 6 weeks. 1

Clinical Assessment Priority

First, systematically screen for red flag symptoms that would alter your management approach:

• Trauma history, prior neck surgery, or spinal cord injury 1
• Constitutional symptoms suggesting malignancy or infection (fever, weight loss, night sweats) 1
• Progressive neurological deficits (weakness, sensory changes, myelopathic signs) 1, 2
• Vascular symptoms in patients >50 years (especially with concomitant vascular disease) 1
• Radicular symptoms (pain radiating into arm with dermatomal distribution) 1
• Tenderness to palpation over vertebral body 1

If any red flags are present, proceed directly to MRI cervical spine without contrast as the preferred imaging modality. 1, 2

Conservative Management Algorithm

First-Line Pharmacological Treatment

• NSAIDs as initial therapy for anti-inflammatory effects and pain relief, effective for 2-12 weeks 2
• Muscle relaxants may be added for muscle spasm if present 3
• Consider short-term use only, as prolonged muscle relaxant use has limited evidence

Physical Therapy Interventions

Sternocleidomastoid-specific interventions have demonstrated superior outcomes compared to conventional therapy alone:

• Combined SCM stretching and massage reduces pain and disability more effectively than conventional physiotherapy alone 4
• Postural correction to minimize SCM tension by maintaining appropriate head position, particularly important for patients with desk work or remote work environments 5
• Treatment sessions 3 times weekly for 5 weeks showed significant improvements in pain, disability, ROM, and endurance 4

Common Pitfall to Avoid

Do not order imaging for uncomplicated neck/SCM pain without red flags. Many acute cases (<6 weeks duration) resolve spontaneously, and imaging rarely alters therapy in the absence of red flags. 1 MRI demonstrates high rates of abnormalities in asymptomatic individuals, leading to unnecessary concern and potential overtreatment. 1

When to Escalate Care

Imaging Indications

Order MRI cervical spine without contrast if: 1, 2

• Symptoms persist beyond 6 weeks despite conservative therapy
• Red flag symptoms develop at any point
• Progressive functional limitations occur
• Radicular symptoms emerge

Radiographs are not first-line but may be considered if you need to rule out gross structural abnormalities, though they rarely change management in the absence of red flags. 1

Specialist Referral Timing

• Urgent referral within 2 weeks for severe pain with functional limitations or any progressive neurological deficits 2
• Routine referral at 4-6 weeks if conservative management fails and symptoms significantly impact quality of life 2

Rare but Important Differential

Consider SCM muscle rupture if there is: 3

• History of hyperextension injury or trauma
• Palpable defect or asymmetry in the muscle
• Acute torticollis with markedly decreased ROM
• Lack of response to conservative therapy

This would require CT or MRI for diagnosis and potentially surgical consultation if fibrotic band formation occurs. 3

Expected Clinical Course

Approximately 50% of patients with acute neck pain may have residual or recurrent episodes up to 1 year after initial presentation, but most improve with conservative management. 1 Reevaluate within 1 month if severe pain or functional deficits persist. 2