Analysis and validation of a 3D finite element model for human forearm fracture.

Most researchers have performed finite element (FE) analysis of the human forearm fracture by exploring the strength and load transmission of the bones. However, few studies concentrated a complete simulation of the whole forearm complex including ligaments. This paper aims to investigate the load transmission through the bones, contact stress at the joints and strain in the ligaments by using an elaborate FE model, further validating the fracture condition for human forearm.

Selective Fiber Degeneration in the Peripheral Nerve of a Patient With Severe Complex Regional Pain Syndrome.

Complex regional pain syndrome (CRPS) is characterized by chronic debilitating pain disproportional to the inciting event and accompanied by motor, sensory, and autonomic disturbances. The pathophysiology of CRPS remains elusive. An exceptional case of severe CRPS leading to forearm amputation provided the opportunity to examine nerve histopathological features of the peripheral nerves.

Impact of Long Flexor Versus Intrinsic Dominance in the Generation of Arc of Finger Flexion.

Finger flexion is a composite movement involving both long flexors and intrinsic hand muscles. Previous studies have characterized this but have not investigated differences within the normal population. Were discrete finger motion patterns identified, this could guide rehabilitation programs following flexor tendon surgery.

Anatomic Relationships of the Distal and Proximal Radioulnar Joints Articulating Surface Areas and of the Radius and Ulna Bone Volumes - Implications for Biomechanical Studies of the Distal and Proximal Radioulnar Joints and Forearm Bones.

Background: Previous work from this laboratory has evidenced the biomechanical role of forearm osseoligamentous structures in load transfer of applied forces. It has shown that forces transmitted across the distal radioulnar joint (DRUJ) and proximal radioulnar joint (PRUJ) are similar, though not identical, under axial loading conditions. The purpose of the study was to assess the articulating surface areas of the radioulnar joints and the volumes of the forearm bones addressing the hypothesis that there may be anatomic adaptations that reflect the biomechanical function of the integrated forearm unit.

The Effect of Elbow Extension on the Biomechanics of the Osseoligamentous Structures of the Forearm.

Purpose: To investigate the hypothesis that elbow extension alters the biomechanics of forearm rotation including force transmission in the distal and proximal radioulnar joints (DRUJ and PRUJ) and the interosseous ligament (IOL).

Methods: A cadaver model with a custom-designed jig was used to measure forearm pronosupination ranges, transmitted forces and contact areas across the PRUJ and DRUJ, and tension in the 3 main components of the IOL's central band. Testing with applied loads was undertaken throughout pronosupination with the elbow fully flexed (n = 15) and fully extended (n = 11).

Adipose-derived stem cells: selecting for translational success.

We have witnessed a rapid expansion of in vitro characterization and differentiation of adipose-derived stem cells, with increasing translation to both in vivo models and a breadth of clinical specialties. However, an appreciation of the truly heterogeneous nature of this unique stem cell group has identified a need to more accurately delineate subpopulations by any of a host of methods, to include functional properties or surface marker expression. Cells selected for improved proliferative, differentiative, angiogenic or ischemia-resistant properties are but a few attributes that could prove beneficial for targeted treatments or therapies.

The functional anatomy of forearm rotation.

The elbow, forearm and wrist act as a unified structure to provide a stable, strong and highly mobile strut for positioning the hand in space and for conducting load-bearing tasks. An understanding of the relevant anatomy and biomechanics is important for the surgeon assessing and treating disorders of forearm function. This paper is concerned with illuminating the principles and concepts governing forearm rotation and load-bearing functions.

Sonographic measurements of longitudinal median nerve sliding in patients following nerve repair.

Nerve sliding may be restricted following nerve repair. This could result in increased tension across the repair site and lead to poor functional recovery of the nerve. Ultrasound was used to examine longitudinal median nerve sliding in 10 patients who had previously undergone nerve repair surgery following complete division of the median nerve.

Dynamic skin tension in the forearm: effects of pronation and supination.

Purpose: Longitudinal scars on the radial quadrant of the distal forearm skin envelope are typically observed to be wider than those on the ulnar quadrant and have an increased incidence of hypertrophic change. Forearm rotation movements may produce differential skin tensions within the forearm skin envelope, and this may lead to differential scarring patterns. This study was designed to measure skin tension changes in the forearm as a result of rotational position to see if these would be consistent with the hypothesis that greater tension changes are observed on the radial aspect of the forearm.

The distal radioulnar joint as a load-bearing mechanism--a biomechanical study.

Purpose: A biomechanical study was performed to define the normal profiles of force transmission across the distal radioulnar joint (DRUJ) and their alteration as the result of surgical modification of the joint and its ligaments.

Methods: Twelve cadaver arms were used in this investigation. A custom-made jig was designed to hold the arm and allow axial loading of the hand.

The pulley system of the thumb: anatomic and biomechanical study.

To examine the precise conformation of the annular and oblique pulleys of the thumb flexor sheath, anatomic dissections were undertaken on 14 hands. In all specimens a distinct pulley was found between the A1 and oblique pulleys. This is named the variable annular pulley or Av pulley.