BACKGROUND Intracortical efferent zones in the primary motor cortex for thumb movements, namely thumb flexion, extension, adduction, and abduction, have been described in Macaca mulatta monkeys but not in humans. Even recent cortical mapping based on intraoperative monitoring does not provide information about intracortical efferent zones as it is not ethically possible to search the human moto...

OBJECTIVE Stenosing tenosynovitis of the thumb flexor tendon sheath is also known as trigger thumb. It is an inflammatory process that involves the flexor tendon sheath at the A1 pulley. Successful percutaneous or open treatment of trigger thumb depends on the ability of the clinician to properly predict the location of the A1 pulley. Longitudinal anatomic landmarks can facilitate safe treatmen...

INTRODUCTION Dislocation of the metacarpophalangeal joint (MCPJ) of the thumb is rare in children and delayed presentation of this injury is even more uncommon in the literature. We report two cases, both children, who presented to fracture clinic with a dislocated thumb over one week after initial injury. In each case closed reduction was attempted but failed, and open reduction was necessary....

The aim of the present study was to analyze the hydrodynamic characteristics of a true model of a swimmer hand with the thumb in different positions using numerical simulation techniques. A three-dimensional domain was created to simulate the fluid flow around three models of a swimmer hand, with the thumb in different positions: thumb fully abducted, partially abducted, and adducted. These thr...

A male infant is described with mandibulofacial dysostosis and absent thumbs, consistent with the Nager acrofacial dysostosis syndrome. In addition, the tetralogy of Fallot was present. Major congenital heart malformations occur rarely in this syndrome.

This chapter emphasizes the dilemma of salvage and reconstruction of the congenitally aplastic or hypoplastic thumb without normal cerebrocortical representation for prehensile grasp and pinch. The philosophy of reconstruction of the congenitally anomalous thumb is clearly divergent from thumb reconstruction following trauma. It is difficult to advise parents who seek surgical correction of the...

Splinting for the common osteoarthritis of the carpometacarpal (CMC) joint of the thumb is infrequently described in the literature, but the few splints that are described include one or both adjacent joints. This paper describes the design and biomechanics of a custom-molded thumb CMC immobilization splint that excludes the thumb metacarpophalangeal and wrist joints. The problem of the imbalan...

OBJECTIVE Thumb problems are common in some health professionals such as physical therapists. The purpose of this case-control study is to investigate the influence of clinical experience and different mobilization techniques on the kinematics of the thumb. METHODS Twenty-three participants without exposure to manual techniques (the Novice Group) and fifteen physical therapists with at least ...