Dimple sign

Dimple sign is a clinical sign that is observed during the physical examination of a patient suspected of having a specific type of skin or soft tissue condition, particularly those involving the fascia or fibrous bands beneath the skin. This sign is most commonly associated with conditions such as Dupuytren's contracture and plantar fibromatosis, also known as Ledderhose disease. The presence of the dimple sign indicates a pathological attachment of the skin to the underlying fascial or fibrous structures, which can lead to puckering or dimpling of the skin when certain movements are performed or when the skin is pinched.

Etiology

The dimple sign is indicative of an abnormal fibrous attachment between the skin and the underlying structures. In the case of Dupuytren's contracture, this occurs in the palmar fascia of the hand, leading to progressive hand deformity. In plantar fibromatosis, the fibrous tissue accumulates in the plantar fascia of the foot. The exact cause of these fibrous proliferations is not fully understood, but genetic predisposition, environmental factors, and microtrauma have been implicated.

Clinical Presentation

Patients presenting with conditions that may exhibit the dimple sign typically report a gradual onset of symptoms. In Dupuytren's contracture, this may include difficulty in fully extending the fingers due to nodules and cords forming in the palm. In plantar fibromatosis, patients may notice nodules on the sole of the foot, which can be painful when walking or standing.

Diagnosis

The dimple sign is elicited during physical examination. For Dupuytren's contracture, the examiner may pinch the skin over the affected area or ask the patient to extend their fingers. A similar approach is taken for plantar fibromatosis by examining the sole of the foot. The presence of a dimple or puckering of the skin over the nodules or cords is a positive dimple sign. Imaging studies, such as ultrasound or MRI, may be used to assess the extent of fibrous proliferation but are not necessary for the sign's observation.

Treatment

Treatment of conditions exhibiting the dimple sign varies depending on the severity and the impact on the patient's quality of life. Options may include observation for mild cases, physical therapy, injections (e.g., corticosteroids, collagenase), and surgical interventions for more advanced cases. The goal of treatment is to relieve symptoms and improve function.

Prognosis

The prognosis for patients with conditions exhibiting the dimple sign depends on the severity of the fibrous proliferation and the treatment's effectiveness. Early intervention can help manage symptoms and maintain function, but these conditions can be progressive and may recur after treatment.