In a 65-year-old patient with two months of left shoulder pain who has completed six weeks of physical therapy and is limited to lifting the arm only to shoulder height, should I order an MRI of the left shoulder now?

Order an MRI of the Left Shoulder Now

Yes, you should order an MRI of the left shoulder without contrast for this 65-year-old patient who has completed 6 weeks of physical therapy without adequate improvement and has significant functional limitation (unable to lift arm above shoulder height).

Clinical Reasoning

This patient meets the criteria for advanced imaging based on:

• Age 65 years: In patients over 35 years, rotator cuff disease (tendinopathy, partial tears, or full-thickness tears) is the predominant cause of shoulder pain rather than instability 1
• Failed conservative management: 6 weeks of physical therapy represents an adequate trial of conservative treatment
• Significant functional limitation: Inability to lift the arm above shoulder height suggests substantial pathology, likely a rotator cuff tear
• Duration of symptoms: 2 months of persistent pain indicates this is not a self-limiting condition

Imaging Recommendation

MRI shoulder without contrast is rated 9 (usually appropriate) by ACR guidelines for evaluating suspected rotator cuff pathology in this age group 1. The guideline explicitly states that in patients aged >35 years, instability is predominantly related to rotator cuff disease, making MRI the appropriate diagnostic modality.

Why MRI Without Contrast?

• Full-thickness rotator cuff tears can be accurately identified with conventional non-contrast MRI with high sensitivity and specificity 1
• Critical surgical planning information is provided: tendon retraction, muscle atrophy, and fatty infiltration help determine whether conservative versus operative repair is appropriate, and what type of repair (open, mini-open, arthroscopic, substitute, or muscle transfer) 1
• MR arthrography is reserved for when there's uncertainty between full-thickness versus partial-thickness tears 1

Alternative: Ultrasound

Ultrasound is rated equally (9 - usually appropriate) if local expertise is available 1. However, ultrasound is operator-dependent and limited in evaluating deep shoulder structures and bone marrow 1. Given the need for comprehensive evaluation in a patient who has failed therapy, MRI is preferable unless ultrasound expertise is exceptional at your institution.

What the MRI Will Tell You

The MRI findings will directly impact management decisions:

• Tendon retraction, muscle atrophy, fatty infiltration: These determine surgical candidacy and postoperative prognosis 1
• Full-thickness versus partial-thickness tear: Guides conservative versus surgical approach
• Associated pathology: Labral tears, biceps tendon pathology, glenohumeral arthritis, or acromioclavicular joint disease

Common Pitfalls to Avoid

1. Don't delay imaging indefinitely: While recent evidence suggests most shoulder pain is self-limiting 2, this patient has already completed 6 weeks of therapy without improvement and has significant functional deficit—this is not a benign, self-limiting course

2. Don't order plain radiographs first at this stage: While X-rays are appropriate for initial trauma evaluation 3, this patient has chronic pain without trauma. Radiographs won't change management at this point since you're already suspecting soft tissue pathology

3. Don't assume all shoulder pain needs surgery: The MRI may show asymptomatic findings (10% of rotator cuff tears are asymptomatic) 1, but given her functional limitation, correlation with clinical findings is key

4. Don't order MR arthrography initially: This is invasive and reserved for distinguishing partial from full-thickness tears when conventional MRI is equivocal 1

Clinical Context

The 2026 JAMA review 2 emphasizes that early imaging is not indicated in the absence of significant trauma or suspicious features. However, this patient has already undergone 6 weeks of conservative management—she is beyond the "early" phase. The guideline's caution against early imaging is to prevent overdiagnosis in patients who will spontaneously improve; your patient has demonstrated she is not in that category.

The systematic review of shoulder disorder guidelines 4 confirms that MRI is generally not recommended for early shoulder pain, but recommendations differ for chronic cases and surgical management decisions. Your patient's persistent symptoms and functional limitation after adequate conservative treatment justify imaging now.