Sensory reinnervation of myocutaneous flaps revealed by infrared laser evoked sensations and brain potentials

The aim of this study was to examine the recovery of sensory function in myocutaneous flaps comparing 2 test methods. Eight flaps in 7 patients were examined by using clinical neurological test procedures (CNT) in comparison with psychophysics and evoked brain potentials (LEP) following infrared laser stimuli. The authors found that only 3 out of 8 flaps in 7 patients exhibited signs of reinnervation when tested with CNT. Three grades of reinnervation appeared in 7 flaps when tested with the laser. Grade 1 indicated the recovery of unmyelinated C-fiber function in 7 flaps accounting for the ability to discriminate laser intensities by different degrees of warmth. Grade 2 appeared in 3 of these flaps and was characterized by the additional ability to sense pinprick pain and the elicitation of late components of LEP mediated by thinly myelinated A delta-nociceptors. Grade 3 involved the additional sensibility for superficial touch indicating the recovery of thickly myelinated A beta-fibers noted in 2 of these flaps. The authors conclude that the LEP method is more sensitive than standard neurological test procedures to objectively document early signs of reinnervation after reconstructive flap surgery. This result is promising to investigate greater patient populations comparing different surgical techniques in future studies.     

Laser-evoked potentials: prognostic relevance of pain pathway defects in patients with acute radiculopathy

The radicular pain syndrome is a major problem in public health care that can lead to chronic back and leg pain in 30%. Ischalgia and back pain are the most prominent signs of dorsal root affection. Until now, no clinical or neurophysiological test procedure exists that evaluates the function of the dorsal root and predicts the prognosis of patients suffering from RPS. We have recently demonstrated that laser-evoked potentials (LEP) are able to demonstrate dorsal root damage. With this study, we investigated 54 patients with acute radicular symptoms and compared LEP parameters (side to side difference of latency and amplitude, transformed to a z-score) with their state of health after 3 months to calculate their predictive value for outcome prognosis. Most significantly, the latency difference between the LEP of the affected dermatome relative to the contralateral healthy dermatome was able to predict the prognosis. Latency z score above two demonstrates a 91% specificity (33% sensitivity) for a poor outcome at 3 months. A significant relation between amplitude changes and the main outcome measure could not be shown. Only extreme changes (z score >10) in amplitude show a high specificity for the persistence of ischialgia in particular (specificity 0.94; sensitivity 0.35). All other parameters, such as clinical scores or other LEP parameters, were not able to predict the outcome of patients. We propose that clinical testing using LEP with latency analysis is a useful tool for estimating the course of disease, so that patients with poor predictive parameters can be treated more invasively at early disease stages to avoid persistence of radiculopathy.     

Marginal and internal fit of metal-ceramic crowns fabricated with a new laser melting technology

OBJECTIVES: The purpose of this in vivo investigation was to evaluate the marginal and internal fit of metal-ceramic crowns fabricated with a new laser melting procedure (BEGO Medical, Bremen, Germany), and to investigate the influence of ceramic firing on the marginal and internal accuracy of these crowns. METHODS: After tooth preparation, impression taking using polyvinylsiloxane and model casting, each preparation was contact less scanned by strip-light-projection. The finishing line and the virtual construction of the metal coping were defined by means of a computer. Using CAD/CAM software the metal copings were produced by BEGO Medical (Germany). A base metal alloy (Wirobond C) and a precious alloy (BioPontoStar, both: BEGO Medical) were used in this study with 14 restorations each. The internal and marginal accuracy of the specimens were examined using a silicone indicator paste (Fit Checker, GC, Japan). After setting, the silicone films were embedded in acrylic resin and sectioned four times. Each slice was photographed digitally at 60x magnification for marginal and at 15x magnification for occlusal adaptation, respectively. Using a light microscope the thickness of the silicone layer was measured at 10 reference points, a total of 3360 measurements. This procedure was repeated after the ceramic firing in the dental laboratory and after intraoral adjustment clinically. RESULTS: No statistically significant differences between the two alloys were found at any time. The mean marginal discrepancies ranged from 74 to 99mum for both alloys. The internal gaps ranged from 250 to 350mum. Ceramic firing increased the marginal discrepancies while the internal gaps decreased especially at occlusal surface. However, only in one case a slight statistically significance could be determined (p=0.046). SIGNIFICANCE: The results of this in vivo study show that crowns produced with laser melting technology exhibit a marginal and internal accuracy that is comparable to conventional production procedures.     

Lowering of LDL cholesterol rather than moderate weight loss improves endothelium-dependent vasodilatation in obese women with previous gestational diabetes

OBJECTIVE: Effects of weight loss on vascular function are unknown. We compared, in the face of similar weight loss over 3-6 months, effects of orlistat (120 mg t.i.d., n = 23) and placebo (n = 24) on in vivo endothelial function in a high-risk group of obese (BMI 32.1 +/- 0.4 kg/m(2)) premenopausal nondiabetic women with a history of gestational diabetes. RESEARCH DESIGN AND METHODS: Forearm blood flow responses to intra-arterial infusions of acetylcholine (ACh) and sodium nitroprusside (SNP), body composition, and serum lipids were determined before and after weight loss. RESULTS: Weight loss averaged 7.3 +/- 0.2 kg (8.3 +/- 0.1%) and 7.4 +/- 0.2 kg (8.2 +/- 0.1%) of initial body weight in the orlistat and placebo groups, respectively. Forearm and body compositions changed similarly in both groups. Responses to ACh increased by 41% to the low dose (5.9 +/- 0.6 vs. 8.3 +/- 0.3 for flow in the experimental/control arm, P < 0.01) and by 33% to the high dose (7.6 +/- 0.8 vs. 10.1 +/- 0.6, P < 0.001) in the orlistat group, but they remained unchanged in the placebo group. The blood flow responses to SNP did not differ significantly between the groups. LDL cholesterol decreased significantly in the orlistat group from 3.5 +/- 0.2 to 3.0 +/- 0.1 mmol/l (P < 0.01) but remained unchanged in the placebo group. Within the orlistat group, the decrease in LDL cholesterol correlated significantly with the improvement in the blood flow response to ACh (r = -0.44, P < 0.05). CONCLUSIONS: Orlistat but not moderate (8%) weight loss per se improves endothelial function in women with previous gestational diabetes. This improvement is associated with a lowering of LDL cholesterol by orlistat.     

Comparison of kyphoplasty and vertebroplasty in the treatment of fresh vertebral compression fractures

Introduction  As life expectancy in the population rises, osteoporotic fractures are seen most frequently in the proximal femur and the vertebral column. In balloon kyphoplasty and vertebroplasty, we have two minimally invasive treatment procedures available. Although they have both been controversially discussed in studies, they have seldom been directly compared. Materials and methods  Between 2002 and 2004, patients with fresh thoracic or lumbar single-segment vertebral compression fractures not involving neurological deficits were treated by balloon kyphoplasty (n = 30) or vertebroplasty(n = 30) using PMMA cement, and the results of the two interventions were compared in a prospective, nonrandomised cohort study. Surgery was indicated when patients had painful, dislocated fractures of type A1 and type A3 according to Magerl’s classification. The outcome of treatment was assessed with special reference to the angle of kyphosis, back pain (VAS), health-related quality of life (SF-36) and complications. Results  At the time of the follow-up examination, significant improvement in the angle of kyphosis was found to have been achieved both by kyphoplasty and by vertebroplasty (P < 0.001 and P = 0.002, respectively). Comparison showed that correction of the angle was significantly (P < 0.001) better in the kyphoplasty group. Both surgical procedures led to significant (P < 0.001) attenuation of the patients’ pain; no difference was observed between the groups in the degree of pain relief achieved. There was no demonstrable correlation in either group between the preoperative pain experienced by the patients and the degree of dislocation of their fractures. In both study groups, the quality of life was in keeping with that of a reference group matched for age and sex. Cement leakage was observed in 7% of patients after kyphoplasty and in 33% of patients after vertebroplasty (P = 0.021). Adjacent-level fractures were checked for, but occurred in only one patient in the vertebroplasty group. Conclusion  The two surgical procedures were both followed by significant pain relief, and the quality of life was similar regardless of the procedure used. Balloon kyphoplasty led to an ongoing reduction of freshly fractured vertebrae and was followed by a lower rate of cement leakage.     

Underlying factors in the association between depressed mood and mobility limitation in older people

BACKGROUND: Depressed mood may either precede mobility limitation or follow from mobility limitation. OBJECTIVE: To compare mood status among people with manifest mobility limitation, those with preclinical mobility limitation and those without mobility limitation and investigate factors explaining the association between depressed mood and mobility limitation. DESIGN: Cross-sectional. Subjects: 645 community-living 75- to 81-year-old people. METHODS: Depressed mood was assessed using the Centre for Epidemiologic Studies Depression Scale (CES-D, cut-off score 16); difficulty walking 500 m was assessed by self-report. Those reporting difficulty were categorised as having manifest mobility limitation. Those with no difficulty but reporting task modifications, such as reduced frequency of walking, were categorised as having preclinical mobility limitation. The association between depressed mood and mobility limitation was analysed using logistic regression analysis with gender, age, economic situation, the availability of a confidant, chronic conditions, and widespread pain as covariates. RESULTS: Depressed mood was found in 34% of subjects with manifest mobility limitation, in 26% of those with preclinical mobility limitation, and in 13% of those without mobility limitation. The unadjusted odds ratio for depressed mood was 3.43 (95% CI 2.04-5.76) among subjects with manifest mobility limitation and 2.38 (95% CI 1.52-3.73) among those with preclinical mobility limitation, compared to those without mobility limitation.Adjustment for covariates reduced the risks to 2.10 (95% CI 1.15-3.82) and 1.99 (95% CI 1.24-3.20), respectively. Widespread pain explained 28% of the increased risk of depressed mood among those with manifest mobility limitation. CONCLUSION: The dose-response relationship between depressed mood and mobility limitation suggests that both conditions may progress simultaneously and may share aetiology, at least in part. Pain may be an underlying factor in both depressed mood and mobility limitation.