What are the potential medical causes and treatment options for significant heel pain during sleep in adults, particularly those with a history of conditions like diabetes or previous trauma to the heel?

Medical Causes of Significant Heel Pain During Sleep

Heel pain during sleep most commonly suggests nerve entrapment (tarsal tunnel syndrome) or inflammatory conditions, as mechanical causes like plantar fasciitis typically improve with rest and worsen with weight-bearing rather than during sleep. 1

Neurologic Causes (Most Likely for Nocturnal Pain)

Nerve entrapment should be your primary consideration when heel pain occurs during sleep, as this presents with burning, tingling, or numbness that can persist at rest and worsen at night. 1

• Tarsal tunnel syndrome causes compression of the posterior tibial nerve and produces medial heel pain that can be constant, including during sleep. 2
• If neurologic heel pain is suspected, immediate subspecialist referral for evaluation and diagnostic testing (electromyography, nerve conduction studies, and MRI) is required. 3

Inflammatory and Systemic Causes

Consider systemic inflammatory conditions, particularly in patients with diabetes or bilateral symptoms, as these can cause constant pain unrelated to mechanical loading. 1, 4

• Infections (soft tissue or bone osteomyelitis) rarely cause heel pain but require immediate diagnostic testing and consultation when suspected, especially in diabetic patients who are at higher risk. 1, 3
• Arthritides can cause heel pain, particularly with bilateral symptoms, pain in other joints, or known inflammatory arthritis conditions. 3
• Vascular compromise can result in heel pain and requires proper diagnostic evaluation, particularly relevant in diabetic patients. 3

Serious Causes Requiring Urgent Evaluation

Tumors and infections present with constant pain at rest or progressively worsening pain without mechanical explanation. 1

• Tumors (malignant and benign) are rare but require appropriate referral when pain is constant at rest. 1, 3
• Seek immediate evaluation if pain becomes constant at rest, or if numbness or increasing swelling/redness develops, to rule out infection or nerve compression. 5

Stress Fractures (Less Likely but Important)

Calcaneal stress fractures can cause pain that persists even at rest in advanced cases, though typically worsen with weight-bearing. 1

• Pain on compression of the calcaneus from medial to lateral (calcaneal squeeze test) is highly suspicious for stress fracture. 1, 3
• Symptoms often occur before the fracture appears on radiographs, requiring technetium bone scanning or MRI for early diagnosis. 1, 3
• History of increased walking activity or change to harder walking surface before symptom onset is typical. 1

Diagnostic Approach for Nocturnal Heel Pain

The location and character of pain guides diagnosis: 3

• Burning, tingling, or numbness strongly suggests neurologic causes requiring immediate referral. 1, 3
• Constant pain at rest, particularly if progressively worsening, requires imaging to rule out tumor, infection, or stress fracture. 1
• Initial weight-bearing radiographs are recommended for persistent heel pain. 1
• If radiographs are negative but pain persists beyond 1 week, MRI without contrast or CT without contrast are equivalent alternatives. 1, 3

Special Considerations for High-Risk Patients

In diabetic patients or those with previous heel trauma, maintain heightened suspicion for infection and vascular compromise. 3

• Diabetic patients require more aggressive evaluation for osteomyelitis and vascular insufficiency. 3
• Previous trauma increases risk for chronic complications including nerve entrapment and post-traumatic arthritis. 3

Common Pitfalls

• Do not assume all heel pain is plantar fasciitis, as this condition typically improves with rest and worsens with first steps in the morning, not during sleep. 2, 6
• Avoid dismissing constant nocturnal pain as mechanical, as this pattern suggests neurologic, inflammatory, or serious pathology. 1
• Never inject corticosteroids near the Achilles tendon due to rupture risk, though this is less relevant for nocturnal pain evaluation. 3, 5