Improving residency training in arthroscopic knee surgery with use of a virtual-reality simulator. A randomized blinded study.

BACKGROUND: There is a paucity of articles in the surgical literature demonstrating transfer validity (transfer of training). The purpose of this study was to assess whether skills learned on the ArthroSim virtual-reality arthroscopic knee simulator transferred to greater skill levels in the operating room. METHODS: Postgraduate year-3 orthopaedic residents were randomized into simulator-trained and control groups at seven academic institutions. The experimental group trained on the simulator, performing a knee diagnostic arthroscopy procedure to a predetermined proficiency level based on the average proficiency of five community-based orthopaedic surgeons performing the same procedure on the simulator. The residents in the control group continued their institution-specific orthopaedic education and training. Both groups then performed a diagnostic knee arthroscopy procedure on a live patient. Video recordings of the arthroscopic surgery were analyzed by five pairs of expert arthroscopic surgeons blinded to the identity of the residents. A proprietary global rating scale and a procedural checklist, which included visualization and probing scales, were used for rating. RESULTS: Forty-eight (89%) of the fifty-four postgraduate year-3 residents from seven academic institutions completed the study. The simulator-trained group averaged eleven hours of training on the simulator to reach proficiency. The simulator-trained group performed significantly better when rated according to our procedural checklist (p = 0.031), including probing skills (p = 0.016) but not visualization skills (p = 0.34), compared with the control group. The procedural checklist weighted probing skills double the weight of visualization skills. The global rating scale failed to reach significance (p = 0.061) because of one extreme outlier. The duration of the procedure was not significant. This lack of a significant difference seemed to be related to the fact that residents in the control group were less thorough, which shortened their time to completion of the arthroscopic procedure. CONCLUSIONS: We have demonstrated transfer validity (transfer of training) that residents trained to proficiency on a high-fidelity realistic virtual-reality arthroscopic knee simulator showed a greater skill level in the operating room compared with the control group. CLINICAL RELEVANCE: We believe that the results of our study will stimulate residency program directors to incorporate surgical simulation into the core curriculum of their residency programs.

Accuracy of magnetic resonance imaging of the knee in the community setting.

BACKGROUND: Magnetic resonance imaging (MRI) is routinely used in the diagnosis of sports-related knee injuries. PURPOSE: To determine the accuracy, sensitivity, and specificity of MRI compared with clinical evaluation in the diagnosis of meniscal pathology when the MRI facility and the radiologist are not preselected. METHODS: A total of 288 knee arthroscopies were retrospectively compared. Patients were divided into 3 groups: those who had MRI performed and interpreted at a single institution, MRI performed and interpreted at community facilities, or a clinical evaluation by a senior orthopaedic surgeon. RESULTS: The sensitivity, specificity, and accuracy of the diagnosis of medial meniscal pathology at a single institution were 90%, 59%, 76%; in community facilities, 73%, 68%, 70%; and by a clinical evaluation, 93%, 55%, 73%, respectively. For lateral meniscal pathology, the results were as follows: single institution, 75%, 76%, 81%; community facilities, 60%, 88%, 79%; and clinical evaluation, 45%, 90%, 79%, respectively. Sensitivity for medial meniscus was greater than for lateral meniscus, but specificity of diagnosis was better for lateral meniscus by MRI and clinical evaluation. While not statistically significant, there was increased sensitivity in the diagnosis of medial meniscus and lateral meniscus at SIs, but they have less specificity than at community facilities. The number of false-positive diagnoses (ie, no intra-articular pathology) that resulted in surgery was 4 of 288 (1.39%). The overall accuracy for medial meniscus by MRI was 73% vs 73% for clinical evaluation. The overall accuracy for MRI for lateral meniscus was 78% vs 79% for clinical evaluation. CONCLUSION: Routine MRI may not be more beneficial than clinical evaluation when there is no preselection of MRI facility and interpreting radiologist. CLINICAL RELEVANCE: The use of MRI for diagnosing meniscal pathology should be reserved for those cases where the orthopaedic clinical examination is ambiguous.

Neural stem cell implantation extends life in Niemann-Pick C1 mice.

In order to evaluate the phenotypic effects of implanted neural stem cells (NSCs) in the mouse model of Niemann-Pick C (NPC) disease, we injected a well-characterized clone of murine NSCs into the cerebella of neonatal Npc1(-/-) and control mice. The implanted cells survived and were abundant in some regions of the cerebellum. Life span was lengthened in NPC mice with the implanted NSCs. However, the rate of weight gain and subsequent weight loss, resulting from neurodegeneration, was not significantly different from un-injected controls. Ataxia was measured by Rota-Rod performance. The overall rate of decline in time on the Rota-Rod was not significantly slowed down. Thus, in this small group of NPC mice, a single administration in the neonatal period of the NSCs (which were not engineered to over-express the missing gene and not directed into the parenchyma) was only partially therapeutic.

Report of a group developing a virtual reality simulator for arthroscopic surgery of the knee joint.

Apprenticeship training of surgical skills is time consuming and can lead to surgical errors. Our group is developing an arthroscopic virtual reality knee simulator for training orthopaedic residents in arthroscopic surgery before live-patient operating room experience. The simulator displays realistic human knee anatomy derived from the Visible Human Dataset developed by the National Library of Medicine and incorporates active force-feedback haptic technology. Our premise is that postgraduate year 2 residents completing a formal virtual education program who are trained to reach a proficiency standard in the techniques and protocol for an arthroscopic knee examination will complete a diagnostic arthroscopy on an actual patient in less time with greater accuracy, less iteration of movement of the arthroscope, and less damage to the patient's tissue compared with residents in the control group learning and practicing the arthroscopic knee examination procedures through the residency program's established education and training program. The validation study, done at eight orthopaedic residency programs, will commence in early 2006 and will take one year to complete. We anticipate that proficiency obtained on the simulator will transfer to surgical skills in the operating room.

Complete, superior labral radial tear and type II slap tear associated with greater tuberosity fracture.

This case report presents a unique variant of superior labral-bicep complex injury. The combination of a complete anterior-superior radial tear of the labrum and bicep anchor instability has not been described in previous classifications of these injuries. The injury was traumatic in nature and was associated with a displaced fracture of the greater tuberosity. The labral pathology was treated by an anatomic repair technique as described. Rationale for the repair performed, as well as implications of the injury treated by debridement alone, are discussed. Clinicians should be aware of different patterns of superior labral-bicep complex injuries and the implications on function and stability of the glenohumeral joint.

Arthroscopic fixation of avulsion fractures of the tibial eminence: technique and outcome.

PURPOSE: The purpose of this study was to review an arthroscopic technique using screw or suture fixation for repair of types II and III fractures of the tibial eminence and review patient outcomes. TYPE OF STUDY: Retrospective review. METHODS: We conducted a review of 17 patients with Meyers and McKeever type II or III fractures of the tibial eminence treated with arthroscopic suture or screw fixation. We reviewed records and administered a questionnaire that included the International Knee Documentation Committee (IKDC) form, Tegner Activity scale, and Lysholm Knee Score. RESULTS: Five men and 12 women comprised the study group. Average age was 26.6 years (range, 7.5 to 60.1 years). Mean follow-up time was 32.6 months (range, 14 to 51 months). The study included 8 type II and 9 type III fractures. At follow-up evaluation, the mean Tegner score was 6.35 and mean Lysholm score was 94.2. In general, the best outcomes were seen in younger patients. For continuous age, significant differences were found for the IKDC functional scores, symptom scores, and IKDC final scores. For categorical age, younger patients had significantly better scores for the IKDC function and final scores. No significant differences were seen in outcomes with regard to fixation type. In 10 cases the intermeniscal ligament was interposed between the avulsed fracture and the tibia and was retracted or resected to allow fracture reduction. No significant differences were seen in the outcomes of these patients. CONCLUSIONS: We found that displaced tibial eminence fractures could be successfully treated in both younger and older patients using arthroscopic suture or screw fixation, with most patients returning to their previous activity levels. The interposed intermeniscal ligament must be retracted or resected to allow for anatomic fracture reduction. LEVEL OF EVIDENCE: Level III, Case Series.

Examen instrumentado de la rodilla: utilización del aparato KT-1000 en lesiones de ligamento cruzado anterior / Instrumental examination of the knee. The use of KT-100 in anterior cruciate ligament injuries

Los aparatos para el examen instrumentado de rodilla han sido descritos, especialmente aquellos que miden la inestabilidad antero-posterior, concluyendo que son aparatos útiles, pero sólo como complemento de un buen examen clínico. Se reportan los resultados de un estudio con el aparato KT-1000, con los objetivos de evaluar si existían resultados similares entre diferentes examinadores, en múltiples periódos de tiempo y valorar el efecto de la presión aplicada a la rótula durante el examen. Siete investigadores examinaron a siete voluntarios en tres diferentes periódos. Se colocó un transductor de presión en la porción rotuliana del aparato. En el tercer periódo de prueba se estandarizó la presión por todos los examinadores. Se evaluó la prueba de cajón manual máximo y de carga de 20 lbs. Se concluye que el aparato es reproducible para el mismo examinador con diferentes voluntarios, pero que los resultados de un investigador no pueden ser comparados a los de otro examinador por la gran variabilidad de respuesta que existe entre los mismos. La presión aplicada en la rótula es muy variable, pero no es necesario estandarizarla para obtener resultados confiables con el aparato

Paragliding Injuries.

In brief This review of 12 paragliding accidents in the Aspen, Colorado, area over a nearly 2-year period identifies causative factors and common mechanisms of injury and assesses the nature and severity of the injuries. Pilot error in judgment was the most frequent cause of accident. Lower-extremity and spinal compression fractures are common during forceful landings. Free-fall accidents, however, typically cause more serious pelvic, chest, and abdominal trauma.