Ex vivo estimation of thoracolumbar vertebral body compressive strength: The relative contributions of bone densitometry and vertebral morphometry

The estimation of vertebral fracture risk in individuals with suspected osteopenia is commonly based on measurements of lumbar spine bone density. The efficacy of vertebral size and deformity, as assessed by vertebral morphometry, in the prediction of fractures has been less studied. In an ex vivo investigation the regional relationships between vertebral size, vertebral deformity, bone density and compressive strength throughout the thoracolumbar spine were examined. In 16 vertebral columns (T1–L5) the bone mineral content (BMC) and bone mineral density (BMD) of each segment were measured using lateral projection dual-energy X-ray absorptiometry, and the vertebral cancellous density (VCD) and mid-vertebral cross-sectional area (CSA) measured using quantitative computed tomography. Vertebral body heights were determined from mid-sagittal CT scans, and vertical height ratios calculated for each segment. The failure load and failure stress of the isolated vertebral bodies were determined using a material testing device. Separate analyses were performed for the upper (T1–4), middle (T5–8) and lower (T9–12) thoracic, and lumbar (L1–5) segments. In all regions, failure load was strongly correlated with BMD (r=0.82–0.86), moderately correlated with VCD (r=0.60–0.71) and vertebral height (r=0.22–0.49), and poorly correlated with the height ratios (r=0.04–0.33). Failure stress was best predicted by BMD (r=0.73–0.78) and VCD (r=0.70–0.78) but was poorly correlated with all morphometric variables (r=0.01–0.33). The segmental correlations between BMD and VCD ranged fromr=0.49 tor=0.79. For all regions, BMD and VCD were included in the stepwise regression models for predicting failure load and failure stress. Either the mid-vertebral height or CSA were included in all the failure load models, while mid-vertebral height was included in only one of the failure stress models. The results suggest that vertebral deformity and size (as assessed by vertebral morphometry) make only a minor contribution to the prediction of vertebral strength additional to that provided by bone densitometry alone. The consistent regional relationships between variables appear to support the practice of global fracture risk assessment based on lumbar spine densitometry.     

Quality of life after myocardial revascularization. Effect of increasing age.

The effect of increasing age on quality of life, survival, and risk of reoperation was studied in 2479 patients followed up prospectively 2 to 20 years after myocardial revascularization. Quality of life was determined from annual questionnaires, which we used to calculate a health status index from the patient's symptomatic status and subjective response to the operation, which was graded between zero and 1.00 (asymptomatic). Four age groups were studied: age 49 years or less (AG40), 50 to 59 years (AG50), 60 to 69 years (AG60), and 70 years or older (AG70). Associated problems (left ventricular aneurysm, valve disease, acute myocardial infarction) necessitating treatment were present in 17% (61/361) of AG40 patients, 19% (165 of 859) of AG50 patients, 23% (213/927) of AG60 patients, and 31% (102/332) of AG70 patients. The hospital mortality rate was higher in older patients undergoing combined procedures but not in patients undergoing coronary bypass grafts only. Probability of survival and health status indexes were calculated excluding patients with valve disease and cardiogenic shock. Probability of survival was significantly better (p less than 0.001 by the Wilcoxon test) in patients less than age 60 than in those 60 years or older, but in patients with an ejection fraction greater than or equal to 0.40, probability of survival at 12 years was 0.64 (age less than 60) versus 0.62 (age greater than or equal to 60). The actuarial risk of reoperation, calculated as the difference between probability of survival and probability of survival without reoperation, progressively increased in younger patients but not in patients aged 60 years or older. At 15 years, the reoperation rates were 26% (AG40), 14% (AG50), 5% (AG60), and 7% (AG70). Mean health status index for years 1 to 5 was 0.85 in AG40 patients, 0.84 in AG50 patients, 0.89 in AG60 patients, and 0.90 in AG70 patients; for years 6 to 10, 0.81, 0.80, 0.86, and 0.89; and for years 11 to 15, 0.77, 0.78, 0.84, and 0.84, respectively. Thus quality of life after myocardial revascularization is better, improvement lasts longer, and reoperation rate is less in patients aged 60 years or older.     

Sociodemographic and behavioral characteristics of HIV antibody-positive blood donors.

This paper describes the sociodemographic and behavioral characteristics of 173 blood donors who were confirmed by Western blot tests to have antibodies to human immunodeficiency virus (HIV), the etiologic agent for acquired immunodeficiency syndrome (AIDS). Seropositive donors were predominantly young, unmarried, and male, and major risk factors could be identified for almost all donors. However, more than 20 per cent of the study participants were women, and many participants were not aware that they were at risk of infection. The heterogeneity of the study population, the lack of awareness among many subjects of risk factors and self-exclusion procedures, and the high level of distress among many subjects after notification, emphasize the need for intensive, well-designed education and support programs.     

Cerebriform intradermal naevus (a rare form of secondary cutis verticis gyrata)

BACKGROUND: Acquired cerebriform intradermal naevus (CIN) is a rare form of pseudo cutis verticis gyrata. CASE REPORT: A case of acquired CIN of the scalp in a 46-year-old male patient is presented. The clinical and histopathological presentations of CIN are described and the therapeutic possibilities are discussed. CONCLUSIONS: In each individual case the physician must decide whether to do surgery or follow a wait-and-see policy. There is little risk of malignant change of CIN, and surgical excision of such lesions often involves evident mutilation.     

Enhanced Reliability and Renewed Applications of the Deltopectoral Flap in Head and Neck Reconstruction

Bakamjian introduced the deltopectoral skin flap in 1965, and thereafter it was used extensively for reconstructive surgery of the head and neck. Flap failure rates of 10% to 25% were reported, necessitating the development of alternative methods of reconstruction and eventually relegating the flap to historical references. Since 1991, we have used the deltopectoral flap in 24 patients for reconstruction after head and neck tumor surgery. Simple technical modifications have been used to enhance the reliability of this flap, with no observed failures or even partial flap loss. The deltopectoral flap remains a versatile and reliable tissue source that can be used simultaneously with the pectoralis major myocutaneous flap for a variety of complex head and neck reconstructions. Laryngoscope, 106:1230-1233, 1996     

Endotracheal suctioning causes right upper lobe collapse in intubated children

Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H₂O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.