The Impact of Musical Training on Hand Biomechanics in String Musicians.

Background: The effects of musical training on the body in professional musicians remain an understudied area, particularly in reference to understanding and managing orthopedic/neuromuscular deviations and injuries in this population. The purpose of this study was to evaluate hand/finger fine motor function in musicians via physical examination as well as laboratory-based evaluations. Methods: Thirteen healthy noninjured young elite string musicians participated in this study. Performance of musicians was compared with healthy age-matched, sex-matched, and handedness-matched nonmusician controls. Results: Musicians exhibited decreased intrinsic muscle strength compared with controls; however, no change in extrinsic muscle strength was found between groups. No between-group differences in overall force control were found; however, Group × Hand (right vs left) interactions were found in force control. Conclusions: These data suggest that musicians are a unique population with respect to: (1) fine motor control of the hand; and (2) exhibit changes in differential hand use. This suggests cortical reorganization of string musicians, such that this population should be studied separately from typical healthy controls with respect to hand function.

Radial ridge excision for symptomatic volar tendon subluxation following de Quervain's release.

Traditional surgical release to address de Quervain's stenosing tenosynovitis can lead to the rare complication of volar tendon subluxation. This study presents a surgical procedure, which entails excision of the radial ridge as an alternative treatment to relieve pain associated with symptomatic volar tendon subluxation following de Quervain's release. The procedure was performed on 6 patients complaining of painful volar tendon subluxation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB), following a first dorsal compartment release and postoperative splinting. We opened the same incision sharply, with direct view of the tendons of the first dorsal compartment. The wrist was ranged through extension and flexion, and volar subluxation of the APL and EPB over the prominent radial ridge was confirmed. The bony portion of the radial ridge was excised and filed smooth. The periosteal flap is advanced over the ridge and sutured into place. The APL and EPB tendons were released from dorsal retractors. All patients reported relief upon follow-up. Excision of this ridge removes the obtrusive friction to the APL and EPB tendons, allowing them to glide painlessly over the radial styloid.

Magnetic resonance imaging technology in evaluating the presence and integrity of the anterior oblique ligament of the thumb.

This investigation examines the reliability and reproducibility of magnetic resonance imaging (MRI) technology in evaluating the anterior oblique ligament (AOL) of the trapeziometacarpal joint (TMC) of the thumb, in order to establish an effective imaging protocol to use in the early identification of conditions leading to degenerative arthritis. We used cadaver specimens, three hand surgeons independently rated from X-rays each specimen. The specimens were then scanned in a General Electric MRI machine with a standard wrist coil. An effort was made to reproduce the image of the AOL - with a unique technique to obtain images of the obliquely oriented thumb and its ligaments. Following the MRI, the specimens were dissected to expose the AOL and visualize the TMC joint. A standard MRI fiducial was sewn to the proximal and distal extent of the volar side of the AOL. The soft tissues were replaced and the skin was closed. They were then rescanned following the same protocol, and pre and post-dissection ligament-labeled specimens were compared. Following dissection and tagging of the AOL ligament, a repeat MRI confirmed its location and validated the protocol in all cases. The open dissection and ligament tagging confirmed that what was visualized was in fact the structure of interest. This investigation demonstrated that with an appropriate MRI protocol it is feasible to guide the scanner to catch appropriate images of a ligament that is closely correlated with degenerative arthritis.

A three-dimensional analysis of the sigmoid notch.

Fractures of the distal radius are among the most common injuries of the upper extremity, though treatment has traditionally focused on restoration of the radiocarpal joint and late sequelae may persist. X-ray imaging underestimates sigmoid notch involvement following distal radius fractures. No classification system exists for disruption patterns of the sigmoid notch of the radius associated with distal radius fractures. This study quantifies the anatomy of the sigmoid notch and identifies the landmarks of the articular surface and proximal boundaries of the distal radioulnar joint (DRUJ) capsule. Computed tomography scans of freshly frozen cadaveric hands were used - followed by dissection, and three-dimensional reconstruction of the distal radius and sigmoid notch. The sigmoid notch surface was divided into two surfaces and measured. The Anterior Posterior (AP) and Proximal Distal (PD) widths of the articulating surface were reviewed, along with the radius of curvature, version angle and depth. The study showed that the sigmoid notch is flatter than previously believed - and only the distal 69% of its surface is covered by cartilage. On average, it has about nine degrees of retroversion, and its average inclination is almost parallel to the anatomical axis of the radius. Clinical implications exist for evaluation of the DRUJ involvement in distal radius fractures or degenerative diseases and for future development and evaluation of hemiarthroplasty replacement of the distal radius.

Imaging and anatomic study of the pisiform bone/ulnar nerve relationship-evaluation of the preferred surgical approach for the excision of the pisiform bone.

This study examines the role of the pisiform bone/ulnar nerve relationship in determining the preferred surgical approach for the excision of the pisiform bone. An anatomic dissection of Guyon's canal on 10 fresh frozen cadaver wrists evenly divided between males and females was combined with magnetic resonance imaging (MRI) scans of 10 volunteer wrists. The 3 reported data points include the axial images determined on the MRI, the anatomic dissection related to the proximity of the ulnar nerve relative to the pisiform in defined positions of the wrist and the soft tissue envelope that surrounds the pisiform, and the proximity of the ulnar nerve as recorded, measured, and analyzed. An analysis of variance of the recorded data points was performed and the statistical results were presented (P value of P 05). Dissection and the MRI scans determined that the soft tissue envelope between the pisiform and ulnar nerve at Guyon's canal with neutral dorsiflexion was 2.5 mm. Palmar flexion was 3.0 mm and neutral flexion was 4.5 mm. The thinnest area was adjacent to the ulnar nerve proper on the volar radial aspect of the pisiform, on the basis of clock-faced analysis, between the 3 : 00 and 6 : 00 positions (the pisiform as a circle). The proximity of the pisiform in relation to the ulna and the limit of the soft tissue envelope would suggest that the preferred surgical approach, or that least likely to cause injury to the ulnar nerve, is one that is volar and includes excising the pisiform after exposing Guyon's canal.

Spider plate fixation: no significant improvement in limited wrist arthrodesis.

Using the Spider plate fixation device, limited wrist arthrodesis was performed on 30 patients over a 2-year period. Developed as an alternative to Kirschner wires and compression bone screws in limited intercarpal fusions, its rigid fixation was expected to yield better results. Five hand surgeons treated 24 men and 6 women with an average age of 45 years. Diagnosis included the following: scaphoid nonunion advanced collapse, scapholunate advanced collapse, scapholunate dissociation, midcarpal arthrosis, and Kienböck disease. The 8-hole regular Spider and 6-hole mini-Spider plates were applied dorsally, and patients were immobilized for 4 weeks. In a blinded study, data results showed no significant improvement when compared with bone screws and Kirschner wires. Preliminary results showed that the Spider plate yielded higher nonunion rates and less wrist motion.