What Causes Cracks in Heels
Heel cracks (fissures) develop primarily from dry skin (xerosis) that loses its elastic properties, combined with mechanical stress from weight-bearing, particularly when peripheral autonomic neuropathy impairs sweating or when hyperkeratosis (callus) accumulates.
Primary Mechanisms
Autonomic Neuropathy and Reduced Sweating
- Peripheral autonomic neuropathy causes deficient sweating, leading directly to dry, cracking skin 1
- This mechanism is particularly important in diabetic patients, where autonomic dysfunction is a well-established risk factor for foot complications 1
Xerosis (Dry Skin) and Loss of Elasticity
- The plantar skin must remain supple and well-hydrated to cope with high levels of frictional, compressive, and shear stresses 2
- When skin becomes dry and loses its elastic properties, painful fissures occur that can act as portals for infection 2
- Age-related tissue degeneration causes progressive skin dryness, making heel cracks increasingly common in older adults 3
Hyperkeratosis (Callus Formation) Leading to Fissuring
- Hyperkeratosis develops as a hyperproliferative response to continuing friction and pressure, and painful cracks can develop within this thickened tissue 1
- The thickened, inflexible callus is more prone to splitting under mechanical stress 1
- Callus formation is reported across multiple conditions including epidermolysis bullosa, diabetes, and normal aging 1, 3
Contributing Mechanical Factors
Footwear Problems
- Ill-fitting shoes are a frequent cause of foot pathology, even in patients with purely mechanical problems 1
- Shoes that are too tight or too loose increase abnormal pressure distribution 1
- Improper footwear contributes to both callus formation and subsequent fissuring 4, 5
Abnormal Pressure Distribution
- Foot deformities (claw toes, hammer toes, bunions, hallux valgus) create areas of excess pressure leading to callus and subsequent cracking 1, 3
- Peripheral motor neuropathy causes abnormal foot anatomy and biomechanics with clawing of toes, high arch, and subluxed metatarsophalangeal joints 1
Secondary Contributing Factors
Metabolic and Systemic Issues
- Hyperglycemia and metabolic derangements impair wound healing and cause excess collagen cross-linking 1
- Vascular insufficiency impairs tissue viability 1
- Crystal deposition arthropathies and peripheral edema in aging populations compound the problem 3
Patient Behaviors
- Inadequate foot hygiene and inspection procedures allow progression of dry skin to fissuring 1
- Excessive weight-bearing increases mechanical stress on already compromised skin 1
Clinical Implications
The key pathophysiologic sequence is: dry skin → loss of elasticity → hyperkeratosis formation → mechanical stress → fissure development 1, 2. This explains why treatment must address both hydration (moisturizers) and mechanical factors (proper footwear, pressure redistribution, callus debridement) 1, 2.