Post-operative Proximal Muscle Pain : Meeting Subclinical Hypothyroidism

 Clinical Profile:

The patient underwent lumbar and scoliosis surgery 3 years ago. 74-year-old female .

Symptoms: Progressive, severe low back, hip, and thigh pain; difficulty standing.

Medications: No statins; regularly takes Lustarl, Buspon, and thyroid medication. Pain has progressively increased since surgery.

Corticosteroid treatment: Deltakort administered with limited effect.

Long-standing thyroid disease.

 Laboratory and Imaging Findings:

TSH: 7.04 (mildly elevated, subclinical hypothyroidism) Free T4: Normal

Cholesterol: 257 mg/dL (likely related to hypothyroidism)

CRP: Normal

ESR: Mildly elevated (35 mm/h)

CK: Normal

MRI: Symmetric edema in thoracis spinalis muscles

Axial T2 FS

Coronal T2 FS

Assessment:

The patient has had thyroid disease for many years and has been stable. However, the postoperative onset and progressive worsening of pain can be explained by the combination of surgical-related muscle sensitization and metabolic effects.

Postoperative muscles have become locally sensitive; trauma and altered muscle use may make edema and pain more pronounced.

Long-standing subclinical hypothyroidism can cause metabolic muscle vulnerability and edema; normal CK reduces the likelihood of inflammatory myopathy.

Mildly elevated ESR may indicate minimal inflammation but is nonspecific.

Differential Diagnosis / Priority:

1. Subclinical Hypothyroid Myopathy (Most Likely)

Symmetric proximal muscle edema and pain are consistent.

Normal CK; progressive symptoms are likely exacerbated by postoperative muscle sensitization.

 2. Postoperative Paraspinal Muscle Sensitization / Degeneration

Local edema and pain, especially near the surgical site, may be

present.

 3. Inflammatory Myopathy (Polymyositis / Dermatomyositis)

Low likelihood given normal CK and only mildly elevated ESR.

 Recommendations / Follow-up:

Measure CK, LDH, aldolase to assess muscle injury.

Endocrinology consult and TSH monitoring; adjust levothyroxine dose if needed.

Physical therapy and pain management.

Consider EMG or muscle biopsy if progression or new findings ap pear.