Long-term outcomes of proximal interphalangeal joint surface replacement arthroplasty.

Background: Surface replacement arthroplasty is a reconstructive alternative for the treatment of pain and deformity due to osteoarthritis and rheumatoid arthritis of the proximal interphalangeal joint of the finger. This retrospective study was performed to examine long-term outcomes of proximal interphalangeal joint prosthetic surface replacement with a proximal cobalt-chromium (CoCr) and distal ultra-high molecular-weight polyethylene component over thirty years at a single institution.

Methods: Sixty-seven prostheses were implanted in forty-seven patients between 1974 and 2007.

Comparative 3D quantitative analyses of trapeziometacarpal joint surface curvatures among living catarrhines and fossil hominins.

Comparisons of joint surface curvature at the base of the thumb have long been made to discern differences among living and fossil primates in functional capabilities of the hand. However, the complex shape of this joint makes it difficult to quantify differences among taxa. The purpose of this study is to determine whether significant differences in curvature exist among selected catarrhine genera and to compare these genera with hominin fossils in trapeziometacarpal curvature.

Long-term outcomes of first metacarpal extension osteotomy in the treatment of carpal-metacarpal osteoarthritis.

Purpose: The purpose of this study was to investigate the long-term outcomes of first metacarpal extension osteotomy in the treatment of osteoarthritis of the thumb carpal-metacarpal joint.

Methods: We retrospectively reviewed 8 patients treated by a single surgeon with first metacarpal extension osteotomy.

Results: Preoperative Eaton stage was I in 3 patients, II in 3 patients, and III in 2 patients.

The clinical implications of scaphotrapezium-trapezoidal arthritis with associated carpal instability.

Purpose: Common causes of dorsal intercalated segment instability (DISI) include scapholunate dissociations and scaphoid fracture nonunions. Although less common than these, scaphotrapezium-trapezoidal (STT) osteoarthritis (OA) may also be associated with the development of a DISI deformity. The clinical implications of this form of carpal instability in cases of STT arthritis are still unknown.

Real-time information-seeking behavior of residency physicians.

Background: Practicing physicians rarely apply evidence-based medicine (EBM). Unlike their more-experienced counterparts, current residents probably participated in EBM curricula during medical school. The current study was designed to determine the extent to which they or their faculty spend time searching for evidence-based answers.

Comparative morphology of the pollical distal phalanx.

Functional analysis of human pollical distal phalangeal (PDP) morphology is undertaken to establish a basis for the assessment of fossil hominid PDP morphology. Features that contribute to the effectiveness of grips involving the distal thumb and finger pulp areas include: 1) distal thumb interphalangeal joint morphology, facilitating PDP conjunct pronation with flexion; 2) differentiation of a proximal, mobile pulp region from a distal, stable pulp region, providing for firm precision pinch grips and precision handling of objects; and 3) asymmetric attachment of the flexor pollicis longus (FPL) tendon fibers, favoring PDP conjunct pronation. A proportionately larger size of the ulnar vs.

Intrinsic stability of an unconstrained metacarpophalangeal joint implant.

Objective: To compare the intrinsic stability of an unconstrained resurfacing metacarpophalangeal arthroplasty to that of a normal human cadaveric joint.

Design: Cadaveric joints and metacarpophalangeal prostheses were studied in a mechanical testing machine at different angles and axial loads to determine the stability ratio in eight directions of movement.

Background: An unconstrained resurfacing arthroplasty was designed to replicate the normal anatomy with the exception of the proximal component having a greater arc of curvature on its dorsal aspect.

Dynamic carpal stability.

The term carpal instability is commonly used, but what carpal stability actually is has not been defined. Much of the mechanically complex wrist's versatility is due to the intercalated three bone proximal carpal row. Landsmeer described the collapse tendency associated with intercalated segments.

Historical perspective of finger joint motion: the hand-me-downs of our predecessors. The Richard J. Smith Memorial Lecture.

Understanding the mechanics of human dexterity requires an appreciation of the kinetic chains that comprise the hand and the intricate interplay of muscles and ligaments that control its movements. Some of the salient contributions to this field are described from a personal point of view in the hope that this perspective will stimulate further understanding of this unique human tool.

Trapezial tilt: a radiographic correlation with advanced trapeziometacarpal joint arthritis.

Trapeziometacarpal (TMC) joint arthritis is a common and debilitating condition of the hand. We defined a radiographic measure of trapezial inclination (trapezial tilt) and found a positive correlation between an increased trapezial tilt and severity of TMC joint arthritis. Radiographs (Robert's views) were obtained from 50 pairs of normal hands to evaluate the trapezial tilt to assess radial inclination of the trapezium with respect to the second metacarpal.

[Complete superficial replacement of the middle finger joint--long-term outcome and surgical technique].

Pain, weakness, malalignment and limited range of motion (ROM) at the PIP joint following arthrosis (degenerative or post-traumatic) or rheumatoid arthritis frequently require surgical treatment. PIP joint fusion or implantation of a prosthetic device are options. The purpose of this study was to report our long-term results with a surface replacement PIP arthroplasty (SR PIP arthroplasty) and the description of our operative technique.

Long-term results of cemented Steffee arthroplasty of the thumb metacarpophalangeal joint.

A retrospective evaluation of the Steffee metacarpophalangeal (MCP) thumb joint prostheses was performed to determine the long-term outcome and survivorship of the prosthesis. Fifty-four primary thumb arthroplasties (49 patients) were performed for pain, weakness, or instability involving the thumb MCP joint secondary to arthritis. Underlying etiology included rheumatoid (49 thumbs), psoriatic (1 thumb), scleroderma (2 thumbs), and degenerative (2 thumbs) arthritis.

Material properties of the trapezial and trapeziometacarpal ligaments.

Destabilization of the trapezium from its normal orientation with respect to the trapezoid, second metacarpal, and thumb metacarpal leads to incongruity at the trapeziometacarpal (TMC) joint. Abnormal shear forces may eventually result in TMC joint arthritis. By determining the relative stiffness and strength of the ligaments that stabilize this joint, one may infer their role in providing stability to the TMC joint.

Implant arthroplasty of the hand: retrospective and prospective considerations.

Small joint arthroplasty has lagged behind the development of that in large joints because of their small sizes, different shapes, presence within kinetic chains, complex soft tissue investments, presence of adjacent rays, secondary displacement and contracture, and the differing requirements of degenerative and rheumatoid arthritis. Prosthetic development must take into consideration range of motion, stability, tendon moment arms, fixation, ease of implantation, biocompatibility, wear and strength characteristics, and soft tissue reconstruction. The metacarpophalangeal, interphalangeal, and trapeziometacarpal joints each present different problems in the design of kinematic equivalent prostheses.

The dorsopalmar stability of the distal radioulnar joint.

Sixteen fresh-frozen adult human cadaveric upper extremities were used in a biomechanical analysis of distal radioulnar joint (DRUJ) stability. The relative contribution to stability of the DRUJ by the surrounding anatomic structures presumed to stabilize the joint was analyzed with respect to forearm rotation and wrist flexion and extension using a purpose-built 4-axis materials testing machine. The dominant structures stabilizing the DRUJ were the ligamentous components of the triangular fibrocartilage complex proper.

Lateral closing wedge osteotomy for treatment of Kienböck's disease. A clinical and biomechanical study of the optimum correcting angle.

A retrospective clinical analysis of 20 patients who underwent a lateral closing wedge osteotomy of the radius as an adjuvant procedure to a radial recession in the treatment of Kienböck's disease is reported. The functional outcome is compared to the results of a simplified two-dimensional articulating force analysis (Rigid Body Spring Model) based on radiographs of the wrist of the same patients taken before and after surgery. At an average follow-up of 39 months, wrist function was excellent in 4 patients, good in 9, moderate in 6, and poor in one patient.

Kinematics of the proximal interphalangeal joint of the finger after surface replacement.

Nine fresh-frozen normal human cadaveric long fingers were used to compare the kinematics of the proximal interphalangeal joint (PIP) before and after a resurfacing metal-polyethylene prosthetic replacement (Avanta prosthesis, San Diego, CA) using the magnetic Isotrak system (Polhemus Navigational Systems, Colchester, VT). The kinematics of the PIP joint after replacement were similar to that of the normal joint. The maximum angular displacement was 5 degrees for lateral deviation and 9 degrees for rotation during the passive flexion and extension motion.

Chimpanzee thumb muscle cross sections, moment arms and potential torques, and comparisons with humans.

This study investigates the morphological basis of differences between humans and chimpanzees in the kinematical and dynamical parameters of the musculature of the thumb. It is partly intended to test an hypothesis that human thumb muscles can exert significantly greater torques, due to larger muscle cross-sectional areas or to longer tendon moment arms or to both. We focus on the estimation of the potentials of thumb muscles to exert torques about joint axes in a sample of eight chimpanzee cadaver hands.

An anatomic study of the stabilizing ligaments of the trapezium and trapeziometacarpal joint.

We provide a detailed and comprehensive anatomic description of the ligaments stabilizing the trapezium and trapeziometacarpal joint. Sixteen ligaments were identified. Fourteen ligaments inserted onto the trapezium and 2 others attached independently to the thumb metacarpal.

Long-term follow-up of pyrolytic carbon metacarpophalangeal implants.

Background: The metacarpophalangeal joint is the most commonly involved joint when rheumatoid arthritis affects the hand. Many prosthetic implants have been designed for the replacement of this joint. Although studies of these implants have shown relief of pain, they have generally demonstrated a poor range of motion, progression of ulnar drift, and bone loss, as well as failure, fracture, and dislocation of the implant.

Biomechanical analysis of the trapeziometacarpal joint after surface replacement arthroplasty.

A biomechanical analysis of the trapeziometacarpal joint was performed in 7 fresh-frozen normal human cadaveric hands to compare the kinematics of the trapeziometacarpal joint before and after surface total joint replacement. Using a 3-space magnetic Isotrak system (Polhemus, Colchester, VT), which provides a 3-dimensional analysis of motion of joints as well as translation, we found that kinematics and stability of the trapeziometacarpal joint could be duplicated by joint surface replacement arthroplasty provided that normal ligament tensions were present.

The lunotriquetral joint: kinematic effects of sequential ligament sectioning, ligament repair, and arthrodesis.

This experiment was conducted to study the effects of sequential sectioning of the ligaments of the lunotriquetral (LT) joint and the effects of simulated repair or arthodesis on kinematics of the wrist joint using an x-ray stereophotogrammetric technique. A 3-dimensional coordinate software program calculated relative motion between bodies as screw axis displacement and rotation about each axis. Sectioning of the proximal and dorsal component of the LT ligament had little effect on carpal kinematics, but sectioning of the proximal and palmar components of the ligament resulted in flexion of both the lunate and triquetrum, producing a volar intercalated segment instability (VISI) pattern.