What is Sclerodactyly?
Sclerodactyly is thickening and tightening of the skin of the fingers and hands, characterized by shiny, tight, hardened skin that restricts finger movement and is a hallmark clinical feature of systemic sclerosis (scleroderma). 1
Clinical Characteristics
Sclerodactyly presents as:
- Skin thickening and hardening that primarily affects the fingers, making the skin appear shiny, tight, and bound down to underlying structures 1
- Progressive flexion contractures of the fingers that develop over time, limiting hand function 2, 3
- Atrophic, dry skin on the dorsal (back) surface of the hands in more advanced cases 2
- Tapered, sausage-like appearance of the fingers due to the sclerotic changes 3
Diagnostic Significance
Sclerodactyly is a key diagnostic finding in systemic sclerosis and helps distinguish it from other conditions: 1, 4
- According to the 2013 ACR/EULAR Classification Criteria, skin thickening of the fingers extending proximal to the metacarpophalangeal (MCP) joints is sufficient alone to classify a patient as having systemic sclerosis 4
- When sclerodactyly is observed during physical examination alongside telangiectasia and digital ulceration, it strongly suggests scleroderma as the underlying diagnosis 1
- The finding helps differentiate systemic sclerosis from other sclerodermoid disorders like scleromyxedema, scleredema, or nephrogenic systemic fibrosis 4
Associated Clinical Features
Sclerodactyly rarely occurs in isolation and is typically accompanied by: 1, 5
- Raynaud phenomenon (episodic color changes in fingers triggered by cold or stress) in nearly all patients 1, 5
- Digital ulcers occurring in approximately 50% of patients with systemic sclerosis 1, 5
- Telangiectasia (visible dilated blood vessels) on hands and face 1, 6
- Calcinosis (calcium deposits in soft tissues) 3, 6
Pathophysiology
The underlying mechanism involves: 4, 3
- Microvascular alterations affecting blood flow to the fingers 4
- Chronic inflammation in early stages 4
- Progressive fibrosis with excessive collagen deposition in the dermis and subcutaneous tissues in advanced stages 4, 3
- Poorly vascularized tissue with deficient soft-tissue envelopes, which increases susceptibility to wound healing complications 3
Clinical Context and Prognosis
Sclerodactyly indicates systemic involvement and warrants comprehensive screening: 1, 5
- Patients with sclerodactyly require screening for interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) using pulmonary function tests, high-resolution CT, and echocardiography 1, 5
- Regular blood pressure monitoring is essential, especially in patients with anti-RNA polymerase III antibodies, to detect scleroderma renal crisis early 1, 5
- The presence of sclerodactyly typically indicates established systemic sclerosis rather than early or prescleroderma stages 1
Important Clinical Pitfall
Do not confuse sclerodactyly with diabetic sclerodactyly (diabetic cheiroarthropathy), which occurs in patients with long-standing diabetes mellitus and presents with similar skin thickening but has a different pathophysiology and does not involve the systemic features of scleroderma. 7 Histopathologic examination can differentiate these conditions when clinical distinction is unclear. 4, 7