Acquisition of surgical skills: a randomized trial of didactic, videotape, and computer-based training.

BACKGROUND: Although computer-based training (CBT) can enhance didactic instruction, few studies have assessed the efficacy of CBT for basic surgical skills training. This study compares CBT with traditional methods of basic surgical skills training. METHODS: Sixty-nine naive medical students were randomized into 3 treatment groups for basic surgical skills instruction: didactic, videotape, or CBT. All instructional material contained the same pictures, text, and audio. With use of a multiple-choice question examination and a series of performance stations, students were objectively assessed before, immediately after, and 1 month after skills instruction. Raters were blinded to treatment modality during the follow-up evaluation. RESULTS: There were no significant differences among the groups before treatment. After treatment, the didactic group scored higher on the multiple-choice question examination. In contrast, the videotape and CBT groups demonstrated statistically significant (P < .01) enhancement of technical skills compared with the didactic group. After 1 month, a calculated performance quotient revealed statistically significant (P < .01) improvement only in the CBT group. The amount of time students spent practicing their skills was not significantly different among the groups. CONCLUSIONS: CBT is as effective as, and possibly more efficient, than traditional methods of basic surgical skills training for medical students.

Management of synovial sarcoma of the median nerve at the elbow.

Synovial sarcoma is a high-grade malignancy with a marked propensity for local recurrence and a moderate rate of regional lymph node involvement. It usually causes death from massive pulmonary metastases. Despite its aggressive biologic behavior, en bloc wide local resection of small extremity tumors rather than amputation may be indicated if removal of all gross disease is possible. Extremity morbidity from resection of vessels, nerves, and soft-tissue bulk can be minimized by the use of composite reconstruction techniques currently available. A case report is presented to illustrate aggressive limb-sparing surgical therapy of a small, favorably located synovial sarcoma with immediate neurovascular and soft-tissue reconstruction. The literature is reviewed to aid subsequent surgeons faced with management of this uncommon tumor.

Internal fixation of malar fractures: an experimental biophysical study.

Open reduction and internal fixation of displaced zygoma fractures are necessary to avoid immediate and delayed facial disfigurement. Interosseous wires, Kirschner wires, and more recently, rigid metallic miniplates have been recommended for fixation of these and other midfacial fractures. However, the precise physical stability of the zygoma with respect to wire versus miniplate fixation methods and with respect to the number and location of miniplates applied is not known. Noncomminuted zygoma fractures were simulated by saw osteotomy in eight fresh human cadaver heads (16 zygoma "fractures"). Each zygoma was sequentially fixated with three miniplates, two miniplates, one miniplate, and three interosseous wires across the orbital rim and arch "fractures". Static and oscillating loads simulating maximal physiologic masticatory stresses were applied to the fixated zygoma along the lines of action of the masseter muscle by means of a tensometer. The stability and adequacy of each pattern of fixation were recorded. Double-miniplate fixation across the orbital rim of simulated noncomminuted zygoma "fractures" is sufficient to withstand static and oscillating loading similar to physiologic masticatory forces. Neither single-miniplate fixation nor triple-wire fixation are sufficient to stabilize the zygoma against similar forces.

Computer-based multimedia in plastic surgery education.

Computer animation complements text explanation, image documentation, and graphic analysis techniques. It is compatible with the development of interactive multimedia science. Computer animation may emerge as a critical tool to assist in the efficient processing and analysis of greater volumes of educational data in plastic surgery training. At St. Louis University, we have continuously developed multimedia plastic surgery teaching materials with full-fidelity digital sound, three-dimensional computer graphics, and "picture-in-picture" video capabilities since 1987. We have used these materials, many of which are illustrated in this paper, for patient informed consent and the education of medical students and residents.

Management of locally aggressive sinus disease using craniofacial exposure and the galeal frontalis fascia-muscle flap.

Histologically, benign sinus diseases can behave aggressively, potentially causing sight- and life-threatening conditions requiring surgical treatment. Four patients illustrating acute and chronic infection, single and multiple sinus polyposis, and mucoceles are presented and discussed to illustrate how the principles of craniofacial exposure, resection, and reconstruction may be employed to treat aggressive sinus disease. The bicoronal and buccal sulcus approaches minimize visible scarring; wide exposure of the orbital contents and dura reduce the risk of excessive bleeding, neurologic complications, and orbital volume derangements. Immediate cranial bone grafting and the well-vascularized galeal-frontalis myofascial flap obliterate the dead space and isolate the extradural space from contaminated facial cavities, diminishing the risk of infection. The craniofacial surgical approach is particularly appropriate for the management of aggressive frontoethmoidal and multiple sinus involvement because it allows the treatment of sinus cavities under direct vision and complete resection of sinus disease.

Three-dimensional surface reconstructions using a general purpose image processing system.

A general purpose two-dimensional (2-D) image processing software system was used to produce high quality three-dimensional (3-D) surface reconstructions from serial sections such as CT scan slices. Depth-encoded 3-D surface images, gradient-shaded 3-D surface images, and weighted sums of these two images were computed. Images that simulate transmission radiographs ("volumetric" views) were created from the same slice data. Hidden surfaces were displayed by reconstructing in 3-D only subvolumes of the original data set. The 2-D image processing functions used were limited to: planar subimage selection and merge, arithmetic and boolean operations, piecewise linear gray scale transform, convolution (1-D), and format conversion (byte-integer-float). Using these methods any user with a general purpose 2-D image processing system can analyze and view multi-slice data as 3-D volume and surface projections.

Mandibulomaxillary fixation with bone anchors and quick-release ligatures.

Mandibulomaxillary fixation (MMF) is an essential technique for accurate treatment of maxillary and mandibular fractures. Traditional techniques of obtaining MMF (circumdental wires and load-distributing arch bars with or without plastic splints) often work poorly in children and adults with partial or absent dentition, require significant operative time, are at risk for glove puncture, and are painful to patients at time of removal. We have developed two new techniques for the rapid establishment of MMF in all ages and all types of dentition with or without splints. These techniques use four bone anchors--two placed in the pyriform rim of the maxilla and two in the mandibular symphysis. "Microlugs" are anchors constructed from Luhr Witallium mesh and are fixated to bone with 0.8-mm microscrews in primary- and mixed-dentition patients. Mitek MiniGII bone anchors are placed for treatment of secondary-dentition patients. Central skeletal MMF is achieved by linking each maxillary bone anchor to each mandibular bone anchor with suture ligatures and heavy orthodontic elastics. In this study, 112 patients (age range, 15 months-75 years) with maxillary and mandibular fractures underwent central skeletal MMF with one of the two new techniques described. Central skeletal MMF was maintained intraoperatively and for up to 6 weeks postoperatively, according to pathological anatomy. Our techniques succeeded with primary, mixed, and secondary dentition, and with splints and dentures, resulting in functional bone healing in 110 of 112 patients. Malocclusion occurred in 2 patients (1.8%), constituting treatment failure. Microlug central skeletal MMF required 15 to 20 minutes to place, and Mitek anchor central skeletal MMF required 7 to 12 minutes to place. There were no glove punctures noted during the course of treatment. Patient satisfaction has been clearly superior with these two techniques, since MMF amy be released in the office with minimal discomfort, even without topical anesthesia.

Computer-based multimedia in plastic surgery education.

Rapid developments in communications networks (cellular telephone, direct-link satellite, and international high-speed computer nets) and the continued success of affordable powerful personal computers (desktop, laptop and soon "palmtop" devices) have set the stage for educational materials accessible by electronic means. Computer-based multimedia are sophisticated audiovisual teaching materials built from digitized illustrations, photographs, audio and video recordings viewed by display on a computer screen. The computer interface allows interactive access to information, and connectivity to other sources of information. Computer programmability allows presentation of a single collection of information at different levels of sophistication (the "patient", "medical student" or "surgeon trainee" level, for example), to appeal to different viewer needs. The information may be electronically updated or changed whenever appropriate. This desktop exhibit demonstrates multimedia plastic surgery teaching materials with full-fidelity digital sound, three-dimensional computer graphics, and "picture-in-picture" video capabilities that we have developed since 1989. We have used these materials at St. Louis University for patient informed consent, and the education of medical students and surgical trainees. We are excited that similar multimedia teaching materials are now becoming commercially available in other fields of medical education, attesting to broadening interest among educators and publishers.

Growing skull fractures: strategies for repair and reconstruction.

Most skull fractures in growing children heal rapidly and without significant contour irregularity. Skull fractures in infants associated with dural injuries, however, may progressively enlarge as a result of bone erosion by leptomeningeal herniation at the dural tear sites and are known as "growing skull fractures." Over a 6-year period, seven growing skull fractures occurred in a population of 592 consecutive pediatric head injuries at Cardinal Glennon Children's Hospital (prevalence, 1.2%). Prompt recognition of growing skull fractures, repair by regional craniectomy and pericranial dural inlay graft, and immediate contour reconstruction with rigidly fixed cranial bone graft ensure reliable aesthetic and functional restoration of the growing neurocranium.

Cranial vault moulding by the transcutaneous activation of implanted magnets.

The technique of distraction osteogenesis has not been widely used in the treatment of injuries of the head and face because of the need for external fixators. By using magnetic, rather than mechanical, forces to drive bone movement we hope to expand the applications of the technique to include the treatment of cranial vault deformities. Fifteen immature rabbits were studied. When they were 6 weeks old each had a magnet fixed to their left parietal bone. A head frame was attached and a magnet of either the opposite polarity to, (group 1), or the same polarity as, (group 2), the implanted magnet was mounted on the frame. Five weeks later the rabbits were sacrificed. There were significant differences in parietal skull width and in several measures of skull length between the animals in group 1 and those in group 2. These results demonstrate that, in this model, magnetic forces can be used to modify skull growth.