Double Crush Syndrome - Features of Etiology, Pathogenesis and Clinical Course

Although carpal tunnel syndrome (CTS) is a diagnosis, which has been known and treated for more than 50 years, nowadays this is a pathology with considerable influence over the quality of life of a large number of patients, having important socio-economic consequences for society. This is a suffering where the pain and the impaired sensation in the palm and wrist area are often accompanied by problems engaging the entire upper limb. Double crush syndrome results from the compression of the same peripheral nerve at two or more levels, which is the cause of a synergistic enhancement of compression-related symptoms. Very often, this syndrome may cause a "blurring" of the clinical picture, which may occur with less typical clinical symptoms, as well as cause insufficient satisfactory results both in the conservative and the operative treatment of CTS. The article is an overview of a number of reports concerning aetiology, pathogenesis, demographic characteristics, and some controversies about epidemiology, risk factors, and pathophysiology of double crush syndrome. The clinical manifestations of the syndrome, as well as the possibilities for functional and instrumental diagnosis are discussed. The uniqueness of the pathology and the symptoms of compression of median nerve at several levels suggest treatment should be conservative at first. Differentiation of double crush syndrome is of particular importance in the therapeutic approach. Although the question of a complete understanding of double crush syndrome remains incomplete, this is a real phenomenon that the therapists of different specialties should consider not only in the case of suspicion of proximal and distal compression of median nerve, but also in some systemic diseases and polyneuropathies. Exact history, correct interpretation of the results of the clinical study, selection of a suitable instrumental diagnostic test are a pledge to find the right approach in its treatment optimally satisfying the patient and the therapist with the outcome of therapy.