Athletes significantly alter their lumbar spinal motion when performing squat lifting at heavy weights. This altered motion effects a change in pressure in the posterior annulus of lumbar discs.
48 athletes performed 6 lifts at 40% maximum, 4 lifts at 60% maximum and 2 lifts at 80% maximum. Zebris 3-D motion analysis system used to measure lumbar spine motion. Exercise then repeated with weight lifting support belt. 4 cadaveric sheep spinal motion segments fixed to tension/compression loading frame, allowing compression replicating the forces seen in in vivo study. Pressure measurement achieved using a Flexiforce single element force sensor strip, positioned at posterior annulus. Posterior annulus pressure measured during axial compression and on compression with specimen fixed at 3° of extension.Hypothesis
Methods
Hip fractures are a significant cause of mortality and morbidity in the elderly. Malnutrition is a major element of this but no consensus exists as to the detection or management of this condition. Reported incidence in elderly hip fracture patients varies widely between 9.0% and 88.6%. The aim of this study was to evaluate the nutritional status of 415 patients with operatively managed hip fractures and determine the prognostic relevance of admission serum albumin and total lymphocyte count (TLC) assays. Protein-energy malnutrition (PEM) was defined as serum albumin <
3.5g/dl and a TLC <
1,500 cells/mm3. Delay to operation, duration of in-patient stay, re-admission (<
3 months) and in-patient, 3- and 12-month mortality were assessed as outcome variables. Survival data was available for 377 patients at 12 months. Of 377 patients, 53% (n=200) had both a serum albumin and TLC levels taken at admission, while 47% (n=177) had not. The incidence of PEM was 51%. Inhospital mortality for PEM patients was 9.8%, compared with 0% for patients with normal values of both laboratory parameters. Older patients were more likely to have lower albumin (p=0.017) and TLC (p=0.023). Nursing home patients were also more likely to have lower albumin (p=0.033). Multivariate analysis revealed a significant difference in 12-month mortality, with patients who had both a low albumin and a low TLC 4.6 times (95% CI: 1.0–21.3) more likely to die within 12 months postoperatively than patients who had normal values of both laboratory parameters. This was significant after adjusting for age, gender and domicile (p=0.049). Serum albumin and TLC in combination are accurate predictors of 12-month mortality in hip fracture patients. These results highlight the relevance of assessing the nutritional status of patients with hip fractures at the time of admission and emphasises the relationship between nutrition and outcome.
3-D motion analysis of lumbar spinal motion in athletes, during squat weight lifting. Pressure measurement of the posterior annulus following the motion analysis study.
4 cadaveric sheep spinal motion segments mounted in purpose built jig, replicating angulation seen in the in vivo motion study. These samples were then fixed to a tension/compression loading frame, replicating the forces seen in the in vivo study. Pressure measurement was achieved using a Flexiforce single element force sensor strip, positioned at the posterior annulus. Posterior annulus pressure was measured during axial compression and on compression with the specimen fixed at 3° of extension.
Significant decrease (p<
0.05) in flexion in all groups when lifting at 40% max was compared with lifting at 60% and 80% of max. Flexion from calibrated zero point ranged from 24.7° (40% group), to 6.8° (80% group). A progressively significant increase (p<
0.05) seen in extension in groups studied when lifting at 40% max was compared with lifting at 60% and 80% max lift. Extension from a calibrated zero point ranged from − 1.5° (40% group), to − 20.3° (80% group). No statistically significant difference found between motion seen when performing the exercise as a ‘free’ squat or when lifting using a support belt in any group studied. Initial uniform rise in measured pressure readings to a pressure of 350–400N, in the axially loaded and extension loaded specimens. Pressure experienced by the axially loaded group then gradually dropped below the pressure exerted by the loading frame, while the pressure experienced in the posterior annulus of the extension loaded specimens progressively increased. Comparing axially loaded specimens with specimens loaded in extension, there was an average increase in pressure of 36.4% in the posterior annulus, when the spine was loaded in 3° of extension at a pressure equivalent to the 80% lift in the in vivo motion study, in comparison to axial loading.
Metastatic bone disease is increasing in association with ever improving medical management of osteophylic malignant conditions. The precise timing of surgical intervention for secondary lesions in long bones can be difficult to determine. This paper aims to validate a classic scoring system. All radiographs were examined twice by 3 orthopaedic oncologists and scored according to the Mirels’ scoring system. The Kappa statistic was used for the purpose of statistical analysis. The results show agreement between observers (κ=0.35–0.61) for overall scores at the 2 time intervals. Inter-observer agreement was also seen with subset analysis of size (κ=0.27–0.60), site (κ=0.77–1.0) and nature of the lesion (κ=0.55–0.81). Similarly, low levels of intra-observer variability were noted for each of the 3 surgeons (κ=0.34, 0.39, 0.78 respectively). These results validate the Mirels’ scoring system across a wide spectrum of malignant pathology. We continue to advocate its use in the management of patients with long bone metastases.
The cervical spine exhibits the greatest range of motion amongst the spinal segments due to its tri-planar components of movement. As a result, measurement of movements has proved difficult. A variety of methods have been used in an attempt to measure these movements but none have provided satisfactory triplanar data. This paper uses the Zebris ultrasonic 3-D motion analysis system to measure flexion, extension, range of lateral bending and range of axial rotation in five similar male and five similar female subjects with no history of neck injuries. The subjects were tested unrestrained and in soft and hard collars, as well as in Philadelphia, Miami J and Minerva orthoses. Results show that the Minerva is the most stable construct for restriction of movement in all planes in both groups (p<
0.001 vs. all groups (p=0.01 vs. Philadelphia in female extension), ANOVA). In the male group, the standard hard collar provides the second best resistance to flexion, lateral bending and axial rotation. The female group showed no one orthosis in second place overall. Looking at these results allows ranking of the measured orthoses in order of their three-dimensional stability. Furthermore, they validate the Zebris as a reliable and safe method of measurement of the complex movements of the cervical spine with low intersubject variability. In conclusion, this paper, for the first time presents reproducible data incorporating the composite triplanar movements of the cervical spine thus allowing comparative analysis of the three-dimensional construct stability of the studied orthoses. In addition, these results validate the use of the Zebris system for measurement of cervical spine motion.