Dimitri J. Anastakis

Assessment of technical skills transfer from the bench training model to the human model.

BACKGROUND This study examines whether technical skills learned on a bench model are transferable to the human cadaver model. METHODS Twenty-three first-year residents were randomly assigned to three groups receiving teaching on six procedures. For each procedure, one group received training on a cadaver model, one received training on a bench model, and one learned independently from a prepared text. Following training, all residents were assessed on their ability to perform the six procedures. RESULTS Repeated measures analysis of variance revealed a significant effect of training modality for both checklist scores (F(2,44) = 3.49, P <0.05) and global scores (F(2,44) = 7.48, P <0.01). Post-hoc tests indicated that both bench and cadaver training were superior to text learning and that bench and cadaver training were equivalent. CONCLUSIONS Training on a bench model transfers well to the human model, suggesting strong potential for transfer to the operating room.

Effect of visual-spatial ability on learning of spatially-complex surgical skills.

Visual-spatial ability is thought to be important in competency in specific surgical procedures. To test this hypothesis, 37 surgical residents completed six tests of visual-spatial ability, ranging from low-level to high-level visual processing. Using previously validated and objective instruments, we then assessed their ability to complete and learn a spatially-complex surgical procedure. Residents with higher visual-spatial scores in the form-board test and the mental-rotations test did significantly better in the procedure than did those with lower scores. After practice and feedback, residents with lower scores achieved a comparable level of competency. Our results suggest that visual-spatial ability is related to competency and quality of results in complex surgery, and could potentially be used in resident selection, career counselling, and training.

Early but No Long-term Benefit of Regional Compared with General Anesthesia for Ambulatory Hand Surgery

Background:The purpose of this study was to determine whether either regional anesthesia (RA) or general anesthesia (GA) provided the best analgesia with the fewest adverse effects up to 2 weeks after ambulatory hand surgery. Methods:Patients undergoing ambulatory hand surgery were randomly assigned to RA (axillary brachial plexus block; n = 50) or GA (n = 50). Before surgery, all patients rated their hand pain (visual analog scale) and pain-related disability (Pain-Disability Index). After surgery, eligibility for bypassing the postanesthesia care unit (“fast track”) was determined, and pain, adverse effects, and home-readiness scores were measured. On postoperative days 1, 7, and 14, patients documented their pain, opioid consumption, adverse effects, Pain-Disability Index, and satisfaction. Results:More RA patients were fast-track eligible (P < 0.001), whereas duration of stay in the postanesthesia care unit was shorter in the RA group (P < 0.001). Time to first analgesic request was longer in the RA group (P < 0.001), and opioid consumption was reduced before discharge (P < 0.001). In the RA group, the pain ratings measured at 30, 60, 90, and 120 min after surgery were lower (P < 0.001), and patients spent less time in the hospital after surgery (P < 0.001). More GA patients experienced nausea/vomiting during recovery in the hospital (P < 0.05). However, on postoperative days 1, 7, and 14, there were no differences in pain, opioid consumption, adverse effects, Pain-Disability Index, or satisfaction. Conclusions:Despite significant reduction in pain before discharge from the hospital after ambulatory hand surgery, single-shot axillary brachial plexus block does not reduce pain at home on postoperative day 1 or up to 14 days after surgery when compared with GA. However, RA does provide other significant early benefits, including reduction in nausea and faster discharge from the hospital.

Visual-spatial ability correlates with efficiency of hand motion and successful surgical performance

BACKGROUND This study examines the influence of visual-spatial ability and manual dexterity on surgical performance across 3 levels of expertise. METHODS Dental students, surgical residents, and staff surgeons completed standardized tests of manual dexterity and visual-spatial ability and were assessed objectively while performing the rigid fixation of an anterior mandible on bench model simulations. Outcome variables included expert assessment of technical performance and efficiency of hand motion during the procedure (recorded using electromagnetic sensors). RESULTS Visual-spatial scores correlated significantly with surgical performance scores within the group of dental students (r=.40 to.73), but this was not the case for residents or staff surgeons. For all groups, manual dexterity did not correlate with hand motion parameters. There were no differences between groups in visual-spatial ability or manual dexterity, but highly significant differences were seen in surgical performance scores (P<.001), in that surgeons outperformed residents, who in turn outperformed students. CONCLUSIONS Among novices, visual-spatial ability is associated with skilled performance on a spatially complex surgical procedure. However, advanced trainees and experts do not score any higher on carefully selected visual-spatial tests, suggesting that practice and surgical experience may supplant the influence of visual-spatial ability over time. Thus, the use of these tests for the selection of residents is not currently recommended; they may be of more use in identifying those novice trainees (ie, those with lower test scores) who might benefit most from brief supplementary instruction on specific technical tasks.

Evaluating the effectiveness of a 2-year curriculum in a surgical skills center

BACKGROUND This study was a formative evaluation of a 2-year Surgical Skills Center Curriculum (SSCC) using objective measures of surgical performance and self-reported process-oriented evaluations. METHODS Fifty postgraduate third-year (PGY-3) residents participated in an Objective Structured Assessment of Technical Skills (OSATS) examination. Nineteen residents underwent the SSCC and 31 residents did not. During the SSCC, self-reported student and faculty evaluations were completed after each session. RESULTS For the OSATS examination, scores were not significantly different between treatment and control groups, on either the checklist (66.4 +/- 6.1 versus 64.1 +/- 10.8) or global rating scale scores (66.9 +/- 6.9 versus 68.0 +/- 9.6). Further comparisons between groups on individual OSATS stations revealed no significant differences between groups. The majority of student and faculty evaluation remarks were highly positive. CONCLUSIONS The OSATS results failed to support our hypothesis that training on a core procedure in a single session during a SSCC would have an appreciable and sustained effect after 2 years. Self-reported process-oriented evaluations support the utility of our SSCC.

Visual-spatial abilities in surgical training

As surgery continues to advance, we will need to better understand the role visual-spatial abilities play in the acquisition of technical skills. Many universities have established surgical skills centers with specific curricula to teach residents technical skills as adjuncts to operating room learning. Yet, as educators we do not fully understand the role visual-spatial abilities plays in the acquisition of surgical skills. This paper summarizes the research to date on the relevance of visual-spatial abilities to surgical training.

Lipofibromatous Hamartoma of the Upper Extremity: A Review of the Radiologic Findings for 15 Patients

OBJECTIVE The purpose of this study was to analyze the radiologic characteristics of lipofibromatous hamartomas affecting upper limb peripheral nerves. CONCLUSION Although there are pathognomonic features that characterize lipofibromatous hamartoma on MRI, the range of appearances is broad. Sonography appears to show equally characteristic features and may be a useful tool for assessing this condition.

Patient-Reported Outcome After Peripheral Nerve Injury

PURPOSE This study evaluated patient-reported outcome and the factors associated with disability after an upper extremity nerve injury. We hypothesized that patients at least 6 months after injury would report considerable disability and that pain would be the strongest predictor of the Disabilities of the Arm, Shoulder, and Hand (DASH) score. METHODS After research ethics board approval, the medical charts of patients with these inclusion criteria were reviewed: adults; presenting to a nerve surgeon; 6 months or greater after nerve injury. Patients completed the DASH questionnaire and the Short Form-36 (SF-36) as a routine part of the initial evaluation. These data were reviewed retrospectively to determine predictors of the DASH score. RESULTS There were 84 patients (mean age, 39 years; SD, 14 years) with brachial plexus (n=27) and peripheral nerve (n=57) injuries. The mean time after injury was 38 months (SD, 47). For all SF-36 domains, the mean values of the nerve-injured patients were significantly lower than the normative data, indicating a lower health status. The mean DASH score was 52 (SD, 22) of 100. Significantly more disability was associated with more SF-36 bodily pain and with brachial plexus injuries. In the final regression model, SF-36 bodily pain, age, and nerve injured were significant predictors of the DASH score. SF-36 bodily pain accounted for 35% of the variance. CONCLUSIONS Substantial long-term disability (high DASH scores) was found in patients after nerve injury that was predicted by higher pain, older age, and brachial plexus injury. Further investigation of this pain and the associated factors may provide the opportunity for improved health-related quality of life. TYPE OF STUDY/LEVEL OF EVIDENCE Prognostic II.

Plasticity of the human motor system following muscle reconstruction: a magnetic stimulation and functional magnetic resonance imaging study.

OBJECTIVE Although motor system plasticity in response to neuromuscular injury has been documented, few studies have examined recovered and functioning muscles in the human. We examined brain changes in a group of patients who had a muscle transfer. METHODS Transcranial magnetic stimulation (TMS) was used to study a unique group of 9 patients who had upper extremity motor function restored using microneurovascular transfer of the gracilis muscle. The findings from the reconstructed muscle were compared to the homologous muscle of the intact arm. One patient was also studied with functional magnetic resonance imaging (fMRI). RESULTS TMS showed that the motor threshold and short interval intracortical inhibition was reduced on the transplanted side while at rest but not during muscle activation. The difference in motor threshold decreased with the time since surgery. TMS mapping showed no significant difference in the location and size of the representation of the reconstructed muscle in the motor cortex compared to the intact side. In one patient with reconstructed biceps muscle innervated by the intercostal nerves, both TMS mapping and fMRI showed that the upper limb area rather than the trunk area of the motor cortex controlled the reconstructed muscle. CONCLUSIONS Plasticity occurs in cortical areas projecting to functionally relevant muscles. Changes in the neuronal level are not necessarily accompanied by changes in motor representation. Brain reorganization may involve multiple processes mediated by different mechanisms and continues to evolve long after the initial injury. SIGNIFICANCE Central nervous system plasticity following neuromuscular injury may have functional relevance.

Chronic pain and sensorimotor deficits following peripheral nerve injury

&NA; Following upper limb peripheral nerve transection and surgical repair (PNIr) patients frequently exhibit sensory and motor deficits, but only some develop chronic neuropathic pain. Thus, the sensorimotor outcome of PNIr may be impacted by individual factors. Therefore, our aims were to determine if patients with chronic neuropathic pain (PNI‐P) following PNIr (1) are distinguished from patients without pain (PNI‐NP) and healthy controls (HCs) by the psychological factors of pain catastrophizing, neuroticism or extraversion, and (2) exhibit more severe sensorimotor deficits than patients who did not develop chronic pain (PNI‐NP). Thirty‐one patients with complete median and/or ulnar nerve transection (21 PNI‐NP, 10 PNI‐P) and 21 HCs completed questionnaires to assess pain characteristics, pain catastrophizing, neuroticism and extraversion and underwent sensorimotor evaluation. Nerve conduction studies revealed incomplete sensorimotor peripheral recovery based on abnormal sensory and motor latency and amplitude measures in transected nerves. The patients also had significant deficits of sensory function (two‐point discrimination and vibration, touch, and warmth detection), sensorimotor integration, and fine motor dexterity. Compared to PNI‐NP patients, PNI‐P patients had higher vibration detection thresholds, performed worse on sensory‐motor integration tasks, had greater motor impairment, and showed more impaired nerve conduction. Furthermore, PNI‐P patients had reduced cold pain tolerance, elevated pain intensity and unpleasantness during the cold pressor test, and they scored higher on neuroticism and pain‐catastrophizing scales. These data demonstrate that chronic neuropathic pain following PNIr is associated with impaired nerve regeneration, profound sensorimotor deficits and a different psychological profile that may be predictive of poor recovery after injury.