Locomotor biomechanics after total sacrectomy: a case report.

STUDY DESIGN: Biomechanical analysis of locomotion after total sacrectomy in a single patient case. OBJECTIVE: To describe the biomechanics of locomotion after successful total sacrectomy and spinopelvic reconstruction. SUMMARY OF BACKGROUND DATA: Total sacrectomy is a complex surgery that has significant consequences for mobility after surgery due to loss of lower lumbar and sacral innervation to the lower extremities, and the anatomic dissociation of the spine from the pelvis. There is no existing literature quantifying locomotor biomechanics after total sacrectomy. METHODS: A 22-year-old female with a sacral osteosarcoma underwent an en bloc sacrectomy with L3 to pelvis instrumented fusion. Neuromuscular function was tested 1 year after surgery using monopolar needle electromyography. Three-dimensional motion capture and surface electromyography were used to quantify spatiotemporal characteristics of locomotion and lower extremity kinematics, kinetics, and muscle function during locomotion at 6 months and 1 year after surgery. RESULTS: Electrodiagnostic testing suggested partial preservation and reinnervation of S1 nerve root function on the right, resulting in greater than expected activity in the hamstrings, gluteus maximus, and triceps surae postsurgically. Unexpectedly on the left, there was residual activity in the hamstrings, despite the loss of sacral innervation and the sciatic nerve. At 1 year after surgery, the patient was able to walk independently. Kinematic and kinetic impairments and compensations were most evident in the sagittal and coronal planes. CONCLUSION: Excellent locomotor outcomes are possible after total sacrectomy.

Assessment of three-dimensional high-definition visualization technology to perform microvascular anastomosis.

BACKGROUND AND AIM: Traditional visualization techniques in microsurgery require strict positioning in order to maintain the field of visualization. However, static posturing over time may lead to musculoskeletal strain and injury. Three-dimensional high-definition (3DHD) visualization technology may be a useful adjunct to limiting static posturing and improving ergonomics in microsurgery. In this study, we aimed to investigate the benefits of using the 3DHD technology over traditional techniques. METHODS: A total of 14 volunteers consisting of novice and experienced microsurgeons performed femoral anastomoses on male Sprague-Dawley retired breeder rats using traditional techniques as well as the 3DHD technology and compared the two techniques. Participants subsequently completed a questionnaire regarding their preference in terms of operational parameters, ergonomics, overall quality, and educational benefits. Efficiency was also evaluated by mean times to complete the anastomosis with each technique. RESULTS: A total of 27 anastomoses were performed, 14 of 14 using the traditional microscope and 13 of 14 using the 3DHD technology. Preference toward the traditional modality was noted with respect to the parameters of precision, field adjustments, zoom and focus, depth perception, and overall quality. The 3DHD technique was preferred for improved stamina and less back and eye strain. Participants believed that the 3DHD technique was the better method for learning microsurgery. Longer mean time of anastomosis completion was noted in participants utilizing the 3DHD technique. CONCLUSIONS: The 3DHD technology may prove to be valuable in improving proper ergonomics in microsurgery. In addition, it may be useful in medical education when applied to the learning of new microsurgical skills. More studies are warranted to determine its efficacy and safety in a clinical setting.

Breast reconstruction satisfaction rates at a large county hospital.

BACKGROUND: It has been previously reported that the indigent patient population is less likely to seek breast reconstruction. It has also been reported that lower income women who do chose to undergo reconstruction are less satisfied with the results. This study assesses the level of breast reconstruction satisfaction in women treated at Los Angeles County Medical Center (LAC). For those women with lower satisfaction, we seek to identify the root source of this dissatisfaction. METHODS: Patients who underwent breast reconstruction at LAC from 2007 to 2012 were identified by Current Procedural Terminology codes. Eligible participants were administered the BREAST-Q postreconstruction module. Demographic data were obtained from the patient and/or their medical records. RESULTS: A total of 65 patients completed the surveys. The satisfaction scores for the appearance of the breast were 61 (24) and satisfaction with overall outcome was 80 (26). The occurrence of major complications was associated with lower satisfaction scores with respect to the appearance of the breast (P<0.0001) and overall outcome (P=0.02). In addition, patients with delayed reconstruction were also noted to be more satisfied with respect to appearance of the breast (P=0.03). CONCLUSIONS: Despite suggestions that the indigent and the underserved patient population are less satisfied with the results of their breast reconstruction procedures, patients at LAC demonstrated comparable satisfaction levels to other published reports. The occurrence of major complications and immediate reconstruction were significantly associated with lower levels of satisfaction.

Determination of a perfusion threshold in experimental perforator flap surgery using indocyanine green angiography.

Indocyanine green (ICG) angiography has been used in the evaluation of flap perfusion but the viability threshold has not been elucidated. In this study, we determined the threshold by comparing perfusion, using ICG imaging (SPY imaging system, LifeCell Corporation), to clinical evidence of nonviability in rat abdominal perforator flaps. Abdominal flaps, based on a single perforator, were elevated and re-inset in Sprague-Dawley rats. ICG imaging and clinical assessments were conducted preoperatively, as well as 0, 24, and 48 hours postoperatively. SPY-Q software allowed standardization of the perforator's perfusion for comparison purposes. A total of 278 random percentage measurements were made from postoperative day 0 giving a mean (SE) percentage perfusion of 26.8% (1.6%) and 59.1% (1.3%), respectively, for necrosis and survival (P<0.05). We demonstrate that ICG angiography can be readily analyzed in a perforator flap environment allowing a determination of the perfusion threshold.

Optimal dose of enoxaparin in critically ill trauma and surgical patients.

BACKGROUND: Low-molecular-weight heparin is effective for prevention of venous thromboembolism. The efficacy of daily dosing in critically ill patients is unknown. METHODS: Seventeen critically ill patients on 40 mg of enoxaparin subcutaneously daily were studied. Anti-Xa activity was measured 4 hours after the third dose and before the fourth dose. Adverse events were recorded. RESULTS: Mean peak anti-Xa activity was 0.19 +/- 0.09 International Units/mL and mean trough was 0.044 +/- 0.04 International Units/mL. The recommended target range is 0.1 to 0.2 International Units/mL. The trough was below therapeutic levels in all but two patients. One thrombosis occurred in a patient despite a therapeutic trough. CONCLUSION: Daily dosing of enoxaparin is inadequate for critically ill patients and should be abandoned. Further studies using twice daily dosing are needed. Patients with renal insufficiency may require an increased interval of administration (daily dosing). Anti-Xa levels may not correlate with the risk of thromboembolic complications. Patients with renal insufficiency and morbid obesity may require alternative dosing and monitoring of anti-Xa levels.

Real-time monitoring of keratin 5 expression during burn re-epithelialization.

BACKGROUND: Keratin is a major protein produced during epithelialization following burn injury and is a useful marker for assessing wound healing. Transgenic mice expressing enhanced green fluorescent protein (EGFP) driven by the keratin 5 (K5) promoter (K5GFP mice) were used to monitor keratin expression, and thus, re-epithelialization of burn wounds. MATERIALS AND METHODS: K5GFP transgenic mice were created using conventional techniques, with PCR and Southern blot confirmation of transgene incorporation, followed by selection of the line with the most intense and consistent basal epithelial EGFP expression. Epi-fluorescent microscopy of 24 K5GFP mouse flanks and 10 negative littermate controls was used to characterize EGFP intensity, before wounding and serially for 30 days after administration of a standardized burn wound and excision. Biopsy sections of K5GFP and negative control mice were stained with K5 antibody and imaged with confocal microscopy to characterize the distribution of EGFP and K5 at baseline and after injury and to examine the correlation between K5 expression and EGFP expression during healing. RESULTS: Green fluorescence intensity increased at the advancing wound margin of burned K5GFP mice, reaching a maximum between days 12 and 15 post-burn and then decreasing as healing completed. K5 and EGFP expression increased in parallel in burned K5GFP mice as demonstrated by confocal microscopy. CONCLUSION: EGFP expression correlated with K5 expression during wound healing and therefore serves as a good marker of re-epithelialization. This transgenic model allows noninvasive, real-time assessment of in vivo K5 expression and will be useful in the study of wound healing.

Elective plastic surgical procedures in adolescence.

Adolescent patients are seeking plastic surgery to correct deformities or perceived deformities in increasing numbers. It is essential for the physician to understand the influence of perceived body image irregularity that motivates patients of all ages to request plastic surgery. The increased demand for plastic surgical procedures among young patients is caused partially to increased media exposure to the available procedures offered by plastic surgeons. A successful aesthetic procedure can have a positive influence on a mature, well-motivated teenager, while surgery on a psychologically unstable adolescent can be damaging to the patient. The American Society for Aesthetic Plastic Surgery has developed guidelines for the appropriate selection of teenagers for aesthetic plastic surgery [26]. First, the physician must "assess physical maturity, because operating on a feature that has not yet fully developed could interfere with growth or negate the benefits of surgery in later years." Second, the physician should explore emotional maturity and expectations of the teenager. The teenager should understand the goals and limitations of the proposed surgery and have realistic expectations. Third, only board certified plastic surgeons who operate in accredited facilities should perform these procedures, to ensure the safety of the teenager and the quality of the procedure. Finally, teenagers and their parents should understand the risks of surgery, postoperative restrictions on activity, and typical recovery times. The referring physician and surgeon must be aware of the positive or negative effects that plastic surgery can have on the life of a teenager and be able to select patients who have the motivation, maturity, psychosocial, and emotional attributes that will lead to patient satisfaction.