Total wrist arthroplasty

With the advent of newer prosthetic designs, total wrist arthroplasty provides a functional range of motion, better wrist balance, reduced risk of loosening, and better implant stability.     

Post-acute brain injury rehabilitation for patients with stroke

Primary objective: Conduct an investigation of post-acute brain injury rehabilitation (PABIR) for persons with stroke.

Research design: Pre-post-treatment observation study.

Methods and procedures: Demographic and medical data for 127 persons with stroke admitted for PABIR at a median interval of 87 days post-stroke were abstracted from medical records. Participants' levels of independence and productivity were assessed at admission and discharge. Follow-up data were available for 90 participants at a median interval of 346 days post-discharge.

Experimental interventions: Not applicable.

Main outcomes and results: Participants showed improvements in productivity and independence level from admission to discharge and these gains were maintained at follow-up. Predictors of productivity at discharge were gender and level of independence at admission (Model R² = 0.28). Predictors of independence at discharge were similar (Model R² = 0.37).

Conclusion: While this investigation has limitations, findings suggest that PABIR is beneficial for some persons with strokes.     

Hemodynamic and metabolic responses to hypergravity on a human-powered centrifuge

INTRODUCTION: Microgravity causes the deconditioning of many physiological systems, and there is great interest in developing effective countermeasures. We recently developed a short-arm human-powered centrifuge, and the primary objective of this study was to assess the hemodynamic and metabolic responses to exercise under hypergravity conditions. METHODS: Phase I compared the hemodynamic and metabolic responses to 1 Gz (upright cycle ergometry) and 2 Gz conditions (Space Cycle) at the same work rate. Phase II contrasted the hemodynamic and metabolic responses at 2 and 3 Gz and at the same work rate. Phase III examined the BP and heart rate (HR) responses during passive and active centrifugation. Phase IV examined the relationship between work rate and oxygen uptake. RESULTS: In Phase I, the HR and BP responses were very similar between the two Gz conditions, with the exception that 2 Gz produced a lower diastolic BP in female subjects. In Phase II, both systolic and diastolic BPs were similar under the two different Gz conditions. However, there was a significant increase in HR at 3 Gz. In Phase III, the slope of the HR/Gz relationship was greater for passive conditions, suggesting that venous return is facilitated by the skeletal muscle pump. In Phase IV, it was found that there was a highly linear relationship between work rate and oxygen uptake. CONCLUSION: The results of this study demonstrate that exercise under low hypergravity conditions on the Space Cycle is well tolerated from a hemodynamic perspective.     

Myocardial oxygen demand and redox state affect fatty acid oxidation in the potassium-arrested heart

BACKGROUND: Fatty acid (FA) metabolism is suppressed under conditions of cardioplegic arrest, but the mechanism behind this effect is unknown. We hypothesized that alterations in redox state and oxygen demand control myocardial FA utilization during potassium arrest. METHODS: Rat hearts were perfused with Krebs-Heinseleit buffer containing physiologic concentrations of FAs, ketones, and carbohydrates with unique (13)Carbon labeling patterns. Cytosolic and mitochondrial redox states were altered by manipulating the lactate/pyruvate and ketone redox couples, respectively. Myocardial oxygen consumption was increased by adding the mitochondrial uncoupler 2,4-dinitrophenol to the perfusate. Experiments were conducted under conditions of normokalemic perfusion and potassium cardioplegia (PC). Substrate oxidation rates were derived from (13)Carbon isotopomer data and myocardial oxygen consumption. RESULTS: Continuous perfusion under conditions of potassium arrest dramatically reduced fatty acid oxidation. Both the addition of 2,4-dinitrophenol and alteration of mitochondrial redox state significantly increased FA oxidation during PC. In contrast to normokalemic perfusion, altering cytosolic redox state during PC did not change FA oxidation. CONCLUSIONS: These data suggest that mitochondrial redox state and oxygen demand are important determinants of myocardial FA oxidation during potassium arrest. FA oxidation appears to be regulated by different factors during PC than normokalemic perfusion.     

Continuous and intermittent exercise responses in individuals with chronic obstructive pulmonary disease

BACKGROUND: While the acute physiological responses to continuous exercise have been well documented in individuals with chronic obstructive pulmonary disease (COPD), no previous study has examined the response to intermittent exercise in these patients. METHODS: We examined the physiological responses of 10 individuals with moderate COPD (forced expiratory volume in 1 second 52 (15)% predicted) who performed both an intermittent (1 min exercise and rest intervals) and a continuous cycle ergometer test on separate days. Both intermittent and continuous exercise tests were performed at the same power output, calculated as 70% of the peak power attained during an incremental exercise test. RESULTS: Intermittent exercise was associated with significantly lower values for oxygen uptake, carbon dioxide output, expired ventilation, heart rate, plasma lactate concentration, and ratings of breathlessness than continuous exercise. Subjects were able to complete a significantly greater total amount of work during intermittent exercise (71 (32) kJ) than during continuous exercise (31 (24) kJ). The degree of dynamic lung hyperinflation (change in end expiratory lung volume) was significantly lower during intermittent exercise (0.23 (0.07) l) than in continuous exercise (0.52 (0.13) l). CONCLUSIONS: The greater amount of work performed and lower measured physiological responses achieved with intermittent exercise may allow for greater peripheral training adaptations in individuals with more limited lung function. The results suggest that intermittent exercise may be superior to continuous exercise as a mode of training for patients with COPD.     

Bowel vaginoplasty in children: a retrospective review

Background/purpose

There are numerous congenital genitourinary conditions that result in vaginal agenesis or atresia. Reconstruction presents a challenge to the surgeon who wishes long-term functional and cosmetic results with low morbidity. Historically, reconstruction has involved the use of skin grafts and nonoperative methods with less than ideal results. The preference of the authors is to use intestinal segments for creating the neovagina and herein review their experience with this procedure.

Methods

The authors identified 10 children who underwent vaginal construction with intestinal segments from 1996 to the present. Patient charts were reviewed for etiology, procedure performed, operative and postoperative complications, and follow-up.

Results

Average age at surgery was 10.9 years (1 to 29 years). Of the 10 children, 3 required vaginal construction for cloacal extrophy, and 7 had vaginal atresia of various etiology. Sigmoid colon was utilized in 6 cases, ileum in 2, and, in 2 patients with high imperforate anus, their mucous fistula segment was used to create the vagina. Mean follow-up was 24 months. Complications included a right ureteral injury necessitating placement of an indwelling ureteral stent and a girl presenting with cyclic pelvic pain who required reanastomosis of the neovagina to the uterus for an obstructed cervical os.

Conclusions

Intestinal segments can be used successfully for creation of a neovagina with exceptional cosmetic results and an acceptable complication rate. In appropriate patients, the mucous fistula can be used to create the vagina obviating the need for a bowel anastomosis.     

Chest wall lipoblastoma in a seven-month-old girl: a case report

Lipoblastoma is a rare benign tumor of adipose tissue seen almost always in infanthood and early childhood. It is typically located in the extremities and the trunk and less frequently in the head-neck region, mediastinum, and retroperitoneum. However, cases of pleural, thoracic wall, and pulmonary lipoblastoma have also been reported in the literature. Lipoblastoma is a tumor with good prognosis despite its potential for local invasion and rapid growth. Our patient is a 7-month-old girl who was brought to our clinic for a rapidly growing mass in the right hemithorax. With the aim of both diagnosis and treatment, the mass was removed by thoracic wall resection and the resultant defect covered with an absorbable polyglactine mesh. The excised mass was diagnosed pathologically as a benign lipoblastoma. In the postoperative period, the thorax wall was stable, and after 24 months of follow-up no recurrence was observed. In the literature, 4 types of thoracic wall lipoblastomas have been reported, but thoracic wall resection has not been applied in any benign lipoblastoma case. To the best of our knowledge, the only benign lipoblastoma case in which a thoracic wall resection was carried out, with its clinical and histopathologic specifications alongside that in the literature, is presented here for the first time.