Clinical characteristics and results after conservative treatment or interfascicular neurolysis of 100 limbs with spontaneous anterior interosseous nerve palsy: A prospective Japanese multicenter study.

Background: Spontaneous anterior interosseous nerve (AIN) palsy is characterized by the sudden onset of upper limb pain followed by weakness of muscles mainly innervated by the AIN. Although this palsy is conventionally treated conservatively, interfascicular neurolysis to release hourglass-like fascicular constrictions has been recommended. The present study aimed to establish the clinical characteristics and treatment strategy for this condition.

Study of Reliability and Validity of the Load Cell-Type Hand Dynamometer Compared to the Jamar Dynamometer and the Number of Reliable Grip Strength Measurements.

Standardised measurement protocols for grip strength remained unclear due to variations in values depending on the device and measurement method. The load cell hand dynamometer has recently been developed. This study aims to investigate the reliability of the load cell dynamometer by comparing it to the Jamar dynamometer, which is considered the gold standard, and to identify a reliable and practical measurement method.

Range of Motion after the Sauvé-Kapandji and Darrach Procedures without Extensor Tendon Rupture.

 Previous study demonstrated that distal radioulnar joint (DRUJ) plays a biomechanical role in extension and flexion of the wrist and suggested that fixation of the DRUJ could lead to loss of motion of the wrist. Little is known about the pre- and postoperative range of motion (ROM) after the Sauvé-Kapandji (S-K) and Darrach procedures without tendon rupture. To understand the accurate ROM of the wrist after the S-K and Darrach procedures, enrollment of patients without subcutaneous extensor tendon rupture is needed.

A Prospective Randomized Comparison of Variable-Angle and Fixed-Angle Volar Locking Plating for Intra-Articular Distal Radius Fractures.

Purpose: To compare clinical and radiographic outcomes of using a variable-angle volar locking plate (VAVLP) with those of using a fixed-angle volar locking plate (FAVLP) for treating unstable intra-articular fractures of the distal radius.

Methods: One hundred twenty patients with unstable intra-articular fractures of the distal radius were randomized to open reduction and internal fixation with a VAVLP (n = 60) or an FAVLP (n = 60). Supplementary methods (eg.

Effects of peripheral tears of the triangular fibrocartilage complex on distal radioulnar joint stability: A biomechanical study.

Background: Peripheral triangular fibrocartilage complex (TFCC) tears may induce instability of the distal radioulnar joint (DRUJ). In this biomechanical study, simulated peripheral tears of the TFCC were examined on the stability of the DRUJ. Restabilization effect of the DRUJ by ulnar shortening and direct repair of those injuries were sequentially examined.

Normal values and ranges of the lateral capitello-humeral angle in healthy children.

The lateral capitello-humeral angle (LCHA), which is an index of sagittal alignment of the elbow, has gradually been adopted for the postoperative assessment of radiographic results. However, the normal values and ranges of the LCHA remain unclear. A retrospective cohort study was performed to evaluate the normal values and ranges of the LCHA in a sample of healthy children with even distributions of age, sex and laterality.

The Effect of Dorsal Angulation on Distal Radioulnar Joint Arthrokinematics Measured Using Intercartilage Distance.

 The effects of dorsal angulation deformity on in vitro distal radioulnar joint (DRUJ) contact patterns are not well understood.  The purpose of this study was to utilize intercartilage distance to examine the effects of forearm rotation angle, distal radius deformity, and triangular fibrocartilage complex (TFCC) sectioning on DRUJ contact area and centroid position.  An adjustable implant permitted the creation of simulated intact state and dorsal angulation deformities of 10, 20, and 30 degrees.

Normal value and range of the humerus-elbow-wrist angle in a sample of healthy children with even distributions of age, sex, and laterality.

This study was performed to evaluate the normal value of the humerus-elbow-wrist angle (HEWA) in a sample of healthy children with even distributions of age, sex, and laterality. A total of 168 radiographs of the elbows of healthy children with even distributions of age, sex, and laterality were reviewed. The mean HEWA was 12.

The Effect of Dorsally Angulated Distal Radius Deformities on Carpal Kinematics: An In Vitro Biomechanical Study.

Purpose: The purpose was to quantify the effect of distal radius dorsal angulation (DA) on carpal kinematics and the relative roles of the radiocarpal and midcarpal joints during wrist motion.

Methods: Six cadaveric specimens (69 ± 17 y) were mounted at 90° elbow flexion in a custom wrist motion simulator. The wrist was guided through planar passive flexion and extension motion trials (∼ 5°/s).

Effect of decrease in radial inclination of distal radius fractures on distal radioulnar joint stability: a biomechanical study.

We investigated the relationship between the radial inclination of the distal radius and distal radioulnar joint stability. Six fresh-frozen upper extremities were used. Radial inclination was decreased by 10° and 20° and increased by 10° from the original radial inclination.

Arthrokinematics of the Distal Radioulnar Joint Measured Using Intercartilage Distance in an In Vitro Model.

Purpose: Current techniques used to measure joint contact rely on invasive procedures and are limited to statically loaded positions. We sought to examine native distal radioulnar joint (DRUJ) contact mechanics using nondestructive imaging methods during simulated active and passive forearm rotation.

Methods: Testing was performed using 8 fresh-frozen cadaveric specimens that were surgically prepared by isolating muscles involved in forearm rotation.

Biomechanical Evaluation of Carpal Kinematics during Simulated Wrist Motion.

 Flexion and extension of the wrist is achieved primarily at the radiocarpal and midcarpal joints. Carpal kinematics have been investigated, although there remains no consensus regarding the relative contribution of each bone to wrist motion.  To determine the kinematics of the scaphoid, lunate, and capitate during unconstrained simulated wrist flexion/extension and to examine the effect of motion direction on the contribution of each bone.

Effect of Volarly Angulated Distal Radius Fractures on Forearm Rotation and Distal Radioulnar Joint Kinematics.

Purpose: To examine the effect of volar angulation deformities of the distal radius with and without triangular fibrocartilage complex (TFCC) rupture on forearm range of motion and the kinematics of the ulnar head at the distal radioulnar joint (DRUJ) during simulated active forearm rotation.

Methods: Volar angulation deformities of the distal radius with 10° and 20° angulation from the native orientation were created in 8 cadaveric specimens using an adjustable apparatus. Active supination and pronation were performed using a forearm motion simulator.

Volar subluxation of the ulnar head in dorsal translation deformities of distal radius fractures: an in vitro biomechanical study.

Objectives: To quantify the effects of dorsal translation deformities of the distal radius with and without dorsal angulation on volar displacement of the ulnar head during simulated active forearm rotation, both with the triangular fibrocartilage complex (TFCC) intact and sectioned conditions.

Methods: Eight fresh-frozen cadaveric upper extremities were mounted in an active forearm motion simulator, and distal radial deformities of 0, 5, and 10 mm of dorsal translation with 0, 10, 20, and 30 degrees of dorsal angulation were simulated. Volar displacement of the ulnar head at the distal radioulnar joint as a result of each distal radial deformity was quantified during simulated active supination.

Evaluation of a computational model to predict elbow range of motion.

Computer models capable of predicting elbow flexion and extension range of motion (ROM) limits would be useful for assisting surgeons in improving the outcomes of surgical treatment of patients with elbow contractures. A simple and robust computer-based model was developed that predicts elbow joint ROM using bone geometries calculated from computed tomography image data. The model assumes a hinge-like flexion-extension axis, and that elbow passive ROM limits can be based on terminal bony impingement.

Distal radioulnar joint kinematics in simulated dorsally angulated distal radius fractures.

Purpose: To examine the effects of dorsal angulation deformities of the distal radius with and without triangular fibrocartilage complex (TFCC) rupture on the 3-dimensional kinematics of the distal radioulnar joint (DRUJ) during simulated active motion.

Methods: Nine fresh-frozen cadaveric specimens were tested in a forearm simulator that produced active forearm rotation. Dorsal angulation deformities of the distal radius with 10°, 20°, and 30° angulation were created.

Identifying the location and volume of bony impingement in elbow osteoarthritis by 3-dimensional computational modeling.

Purpose: To determine the locations and volumes of bone requiring resection to restore range of motion in patients with osteoarthritis of the elbow, using computational modeling.

Methods: A total of 30 patients with primary osteoarthritis of the elbow and restricted range of motion underwent computed tomography. We used the computed tomography data to generate 3-dimensional models.

Treatment of Distal Radial Fractures with an Intramedullary Nail.

Introduction: This paper will describe the surgical technique for the treatment of unstable distal radial fractures with use of the MICRONAIL Intramedullary Distal Radius System (Wright Medical Technology, Arlington, Tennessee).

Step 1 Closed Reduction And Pinning: The fracture must be adequately reduced and pinned prior to nail insertion.

Step 2 Perform Exposure And Enter Canal: Protect the branches of the superficial radial sensory nerve at all times.

Prospective study of distal radial fractures treated with an intramedullary nail.

Background: Intramedullary nailing for the treatment of unstable distal radial fractures is reported to provide stable fixation with minimal soft-tissue complications, but there is a paucity of data documenting the results of this technique. The purpose of this study was to prospectively determine the functional outcomes of treatment of unstable distal radial fractures with an intramedullary nail.

Methods: Patients aged fifty years and older with a dorsally displaced unstable distal radial fracture--an extra-articular or simple intra-articular fracture--that was amenable to closed or percutaneous reduction were offered treatment with intramedullary nail fixation (MICRONAIL).

Ulnar-shortening effect on distal radioulnar joint pressure: a biomechanical study.

Purpose: The ulnar-shortening procedure has been successfully used to relieve ulnar impaction syndrome and may help in stabilizing the distal radioulnar joint (DRUJ) by increasing the tension within the triangular fibrocartilage complex. This procedure, however, may increase pressure at the DRUJ and possibly induce degenerative changes in the joint. This study aimed to examine the changes in pressure at the DRUJ by simulating the ulnar-shortening procedure in intact and torn states of the triangular fibrocartilage complex.

Ulnar shortening effect on distal radioulnar joint stability: a biomechanical study.

Purpose: The ulnar-shortening procedure has been adopted widely to reduce pressure between the ulna and ulnar carpus in ulnocarpal abutment syndrome. The hammock-like structure of the triangular fibrocartilage complex (TFCC), which supports and connects the ulnocarpal and distal radioulnar joint (DRUJ), variably is torn in this condition. The degree to which the torn TFCC may be tensioned to restabilize the DRUJ with ulnar recession is uncertain.

Locking of the thumb in a patient with de Quervain's disease: a case report.

We report a patient with a locked left thumb in association with de Quervain's disease. While bathing her baby 1 month after giving birth a 32-year-old woman suddenly noticed that she could not radially abduct her left thumb. Magnetic resonance imaging showed thickening of the abductor pollicis longus tendon with a heterogeneous signal intensity on T2-weighted images.