Influence of the number of cortices on the stiffness of plate fixation of diaphyseal fractures.

OBJECTIVE: To determine the influence of the number of cortices of fixation on the stiffness of plate fixation of diaphyseal fractures. DESIGN: Canine experimental study. SETTING: Tertiary referral and teaching hospital in Toronto, Canada. PARTICIPANTS: Paired radii from fourteen skeletally mature, cross-bred dogs. MAIN OUTCOME MEASURE: One member of each pair of radii was tested intact as a control, and the other had a transverse osteotomy plated sequentially with five to ten cortices of fixation on either side of the simulated fracture. Dynamic compression plates and limited contact dynamic compression plates were used in two groups with seven paired radii each. Normalized torsional stiffness and four-point bending stiffness were determined in the elastic range for the control and each of the plated constructs in both groups, using a materials testing machine. RESULTS: The authors found no significant difference between the stiffness of the dynamic compression plates and limited contact dynamic compression plates. With either plate of a given length, significantly increased torsional stiffness is achieved with end bicortical screws. For bending stability with the plate at right angles to the bending plane, even short plated constructs have a stiffness exceeding that of intact bone. CONCLUSIONS: For a transverse osteotomy with no fracture interdigitation, the bending rigidity with the plate at right angles to the bending plane is greater than the original stiffness of the bone for all constructs tested, with the exception of the limited contact dynamic compression plate with five cortices of fixation. The torsional rigidity of fixation only approaches the original rigidity of the bone for ten cortices of fixation with the dynamic compression plate and the limited contact dynamic compression plate.

Evaluation of abdominal sensibility after TRAM flap breast reconstruction.

One commonly expressed concern regarding transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction surgery is the return of sensation to the abdomen. Although many studies have focused on abdominal wall muscle incompetence or herniation, there is limited literature discussing postoperative abdominal sensation. The purpose of this study was to assess abdominal sensation a minimum of 1 year after pedicled TRAM flap surgery for breast reconstruction. Twenty-five female patients who underwent TRAM flap breast reconstruction a minimum of 1 year before the study were compared with 10 female volunteer controls. Subject and control abdomens were specifically divided into 12 zones, then assessed for superficial touch, superficial pain, temperature, and vibration using various techniques. Fischer's exact test was used for analysis with the p value set at p = 0.05. The degree to which superficial touch was affected was then tested using Semmes-Weinstein monofilaments. Student's t test was used for analysis with the p value set at p = 0.05. For all four sensory modalities, subjects were found to have decreased sensation in zones 5 and 8, the supraumbilical and infraumbilical regions. This was statistically significant. When assessed with Semmes-Weinstein monofilaments, the sensation of the subjects' abdomens was significantly decreased compared with controls. Significance was found in all zones. This study clearly demonstrates that there is a significant and persistent reduction in abdominal sensibility following TRAM flap surgery. The distribution of the deficits is consistent and involves the midline supraumbilical and infraumbilical regions. The TRAM flap has become the procedure of choice for postmastectomy autogenous breast reconstruction. It provides the plastic surgeon with a relatively safe, reliable, and aesthetically pleasing method of breast reconstruction. Since its inception, the TRAM flap and its abdominal closure have undergone numerous modifications designed to minimize donor-site morbidity and create a natural-looking breast. In addition to creating an aesthetically pleasing breast, the TRAM flap has the potential advantage of postoperative improvement in abdominal contour.

Anterior oblique ligament reconstruction of the thumb using the transverse carpal ligament: description of a new procedure.

Traumatic dislocation of the thumb carpometacarpal joint is an uncommon injury that may have long-term sequelae after treatment. Joint instability may cause pain, weakness of pinch, and the increased likelihood of development of posttraumatic arthritis. The anterior oblique ligament has generally been accepted as the most important static stabilizer of the trapeziometacarpal joint. Numerous operative techniques have been described to reconstruct this ligament. The author introduces a novel operative procedure to reconstruct the anterior oblique ligament of the thumb using the transverse carpal ligament (AOLR-T). This procedure was performed on 5 fresh-frozen cadaveric hands to assess its feasibility and potential efficacy. No technical difficulties were encountered. AOLR-T may be indicated for the treatment of thumb carpometacarpal instability of primary or secondary etiology and may avoid many of the disadvantages of traditional ligament reconstruction.

Transmetacarpal intramedullary K-wire fixation of proximal phalangeal fractures.

The management of unstable phalangeal fractures has been associated with significant morbidity. Percutaneous transmetacarpal intramedullary Kirschner wire fixation of proximal phalangeal fractures has been described as a useful technique. We present a retrospective review of 35 digits in 24 patients with unstable fractures of the proximal phalanx treated using this technique between 1985 and 1995. Outcome measures, including radiological adequacy of reduction, total active range of motion, development of joint contracture, grip strength, and digital grip strength, were assessed. Good or excellent results were obtained in 76% of fractures (19 of 25) that were treated and followed. Thirty-two percent of digits (8 of 25) treated developed a proximal interphalangeal joint flexion contracture. Flexion contracture averaged 18.1 deg at the involved joints. Seven secondary procedures were required in 6 patients. Major complications noted during the study included loss of reduction with rotational deformity in four digits, and one nonunion. The use of skeletal traction devices was associated with three of the major complications observed. These devices should not be used concurrently on or adjacent to any digit treated by intramedullary pinning. We conclude that transmetacarpal axial Kirschner wire fixation is a technically simple method of treating unstable proximal phalangeal fractures, and good or excellent results can be obtained in the majority of appropriately selected patients.

Single-portal endoscopic carpal tunnel release: agee carpal tunnel release system.

This single-group prospective cohort study was conducted to define the efficacy and safety of single-portal endoscopic carpal tunnel release using the redesigned carpal tunnel release system (3M Healthcare, St Paul, MN). Eighty-six procedures in 69 patients were evaluated by objective motor/sensory testing and clinical outcome questionnaire at 10 days, and 6 and 10 weeks postoperatively. All cases were performed by the same surgeon using a similar local anesthetic technique. The subjective symptoms of carpal tunnel syndrome, including paresthesia, numbness, and pain, demonstrated substantial improvement by 10 days postoperatively, and less than 2% of the subjects remained symptomatic by 10 weeks. The percentage of patients with normal, static, two-point discrimination in the median nerve distribution, demonstrated significant improvement by 6 weeks postoperatively. Preoperative grip and three-point pinch strength were regained by 6 weeks postoperatively, while lateral pinch demonstrated substantial improvement in the same time period. Workers' compensation cases required a significantly longer time to return to work (mean, 40.8 days) than nonworkers' compensation cases (mean, 22.2 days). No difference, however, was demonstrated between workers' compensation and nonworkers' compensation cases with respect to the time of return to activities of daily living (mean, 13.5 days). There were no major neurovascular injuries incurred during the performance of the study. The most important complications included one mild reflex sympathetic dystrophy, three transient digital neuropraxias, and one superficial wound infection. In conclusion, the performance of single-portal endoscopic carpal tunnel release using the redesigned Agee carpal tunnel release system is both a safe and efficacious procedure.