What is the best course of treatment for a 57-year-old female with hypothyroidism (underactive thyroid) and hyperlipidemia (elevated lipid levels) presenting with left hip pain radiating to the left knee for 4 weeks without trauma and a body mass index (BMI) of 26?

Initial Diagnostic Approach for Hip Pain

Begin with plain radiographs of both the pelvis and hip, as these are the first-line imaging studies for evaluating chronic hip pain and are complementary to each other. 1

Imaging Strategy

• X-ray pelvis and X-ray hip are both rated as "usually appropriate" (rating 9/9) for initial evaluation of chronic hip pain and should be obtained together as they provide complementary information 1
• Plain radiographs may be the only imaging necessary if they reveal common disorders such as osteoarthritis or can guide the next steps in the diagnostic pathway 1
• If radiographs are negative, equivocal, or nondiagnostic and you suspect extra-articular soft tissue pathology (such as tendonitis or bursitis), MRI hip without IV contrast is the next appropriate study (rating 9/9) 1

Clinical Examination Findings to Assess

While obtaining imaging, perform targeted physical examination maneuvers that help identify hip osteoarthritis, the most common cause of chronic hip pain in this age group:

• Test passive hip adduction and internal rotation with a goniometer - decreased range of motion has high specificity (81% and 79% respectively) for hip OA 2
• Assess for groin pain on passive abduction or adduction (specificity 94%, LR 5.7) 2
• Observe for abductor weakness (specificity 90%, LR 4.5) 2
• Ask patient to squat and note if this causes posterior hip pain (specificity 96%, LR 6.1) 2
• Normal passive hip adduction is most useful for ruling out OA (negative LR 0.25) 2

Initial Conservative Management

Initiate exercise-based treatment immediately while awaiting imaging results, as this is the cornerstone of management for hip-related pain with moderate-quality evidence. 1

Exercise Therapy Protocol

• Duration: Minimum 3 months of structured exercise therapy 1
• Components: Hip, trunk, and functional strengthening exercises focusing on resistance training 1
• Frequency and progression: Exercise should be prescribed relative to symptom severity and irritability, with progressive loading as tolerated 1

Pharmacologic Management

Start with acetaminophen (paracetamol) up to 4 grams daily as first-line oral analgesic for mild-to-moderate pain, as it has the best efficacy and safety profile for long-term use 1

If acetaminophen provides inadequate relief:

• Add or substitute NSAIDs at the lowest effective dose 1
• For patients with gastrointestinal risk factors, use either non-selective NSAIDs plus gastroprotective agent, or a selective COX-2 inhibitor 1
• Consider opioid analgesics (with or without acetaminophen) only if NSAIDs are contraindicated, ineffective, or poorly tolerated 1

Addressing Comorbidities

Hypothyroidism Considerations

• Ensure the patient's hypothyroidism is adequately treated with levothyroxine, as uncontrolled hypothyroidism can worsen hip symptoms through multiple mechanisms 3, 4, 5
• Hypothyroidism commonly causes musculoskeletal pain and may contribute to the clinical presentation 3

Hyperlipidemia Management

• Verify thyroid function is optimized before intensifying lipid-lowering therapy, as hypothyroidism causes secondary hyperlipidemia that improves with levothyroxine treatment 3, 4, 5
• Type IIa hyperlipidemia is the most common pattern in primary hypothyroidism 5
• Lipid profiles typically improve significantly within 5 months of adequate thyroid hormone replacement 3

Patient Education and Shared Decision-Making

Discuss with the patient that pain does not necessarily correlate with structural damage, particularly important given the 4-week duration without trauma 1

Key educational points:

• Explain the relationship between hip pain and structural findings, including that morphological abnormalities are common in asymptomatic individuals 1
• Set realistic expectations regarding treatment timeline - meaningful improvement typically requires at least 3 months of consistent exercise therapy 1
• Emphasize that physical activity and exercise are recommended and will not harm the hip joint 1
• Use shared decision-making to align treatment with patient goals, whether reducing pain, improving function, or returning to specific activities 1

Monitoring Response to Treatment

Track outcomes using patient-reported outcome measures (PROMs), physical impairment measures, and psychosocial factors 1

Reassess at regular intervals (typically 4-6 weeks initially) to determine if:

• Symptoms are improving with conservative management
• Additional imaging or interventions are needed based on radiographic findings
• Referral to orthopedic surgery is warranted for refractory cases

When to Consider Advanced Interventions

• Image-guided corticosteroid injection may be appropriate (rating 5/9) if rehabilitation is hindered by elevated symptom severity that is unresponsive to analgesics and NSAIDs 1
• Surgical consultation is indicated if there is radiographic evidence of hip OA with refractory pain and disability despite 3+ months of optimal conservative management 1