Cancellous Bone Structure in the Growing and Aging Lumbar Spine in a Historic Nubian Population

There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally, using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material. Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately 50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations was probably prevalent. Received: 1 March 1996 / Accepted: 31 December 1996     

A Study on Extension－Flexion Dynamic Lumbar Spine Radiographsin Patients with Lumbar Intervertebral Disc Herniation

ＡＳｔｕｄｙｏｎＥｘｔｅｎｓｉｏｎ－ＦｌｅｘｉｏｎＤｙｎａｍｉｃＬｕｍｂａｒＳｐｉｎｅＲａｄｉｏｇｒａｐｈｓｉｎＰａｔｉｅｎｔｓｗｉｔｈＬｕｍｂａｒＩｎｔｅｒｖｅｒｔｅｂｒａｌＤｉｓｃＨｅｒｎｉａｔｉｏｎＡＳｔｕｄｙｏｎＥｘｔｅｎｓｉｏｎ－Ｆｌｅｘｉ...     

经椎弓根椎间融合与AF治疗胸腰椎骨折

目的：总结32例经椎弓根椎间融合与AF治疗胸腰椎骨折的经验。方法：应用经伤椎椎弓根椎体间融合并AF系统复位内固定，以提高复位效果与脊柱的稳定性。结果：全部病例获随访，时间3～23个月，伤椎均与上位椎体间融合，无矫正角度与高度丢失，无断钉及螺钉松动，神经功能平均1．5级以上的恢复。结论：经椎弓根椎间融合与AF治疗胸腰椎骨折，操作简单，复位可靠，可重建脊柱的稳定性，椎体间融合更符合生物力学内环境的持久稳定。     

全身热疗法治疗晚期肝脏恶性肿瘤39例报告

目的 探讨全身热疗法（whole body hyperthermia，WBH）治疗肝脏恶性肿瘤的疗效及其对肝功能的影响。方法 采用WBH治疗肝脏恶性肿瘤患者39例，并对治疗前、后患者肝功能指标进行动态观察，分析该疗法对肝脏功能的影响，并通过分析治疗效果，初步评估该疗法的疗效。结果 ①WBH治疗不能手术切除的晚期肝脏恶性肿瘤患者的有效率为61．5％（24／39），60．0％（9／15）的患者AFP有不同程度下降，肿瘤疼痛缓解率达100％；存活期〉2年者占12．8％（5／39），〉1年者占59．0％（23／39），〉6个月者占76．9％（30／39）。②谷丙转氨酶于治疗后1～3d出现明显升高（P〈0．05），7d后下降并接近治疗前水平；谷草转氨酶于治疗后1d明显升高（P〈0．05），3～7d则下降并接近治疗前水平；白蛋白于治疗后1d出现下降（P〈0．05），但3d即已恢复；肝功能正常组总胆红素于治疗后第1～3d出现升高（P〈0．05），而肝功能异常组未观察到同样变化；转肽酶则无明显变化。结论 WBH能改善晚期肝脏恶性肿瘤患者的预后，提高生存质量，延长生存时间，但同时可造成患者肝功能一定程度的可逆性损害。     

Value of polydirectional tomography in the assessment of the postoperative spine after anterior decompression and vertebral body autografting

With the growing number of orthopedic reconstructive spinal procedures, the use of bone grafting has steadily increased in the past decade. An understanding of the biology of bone grafting is essential for both the clinician and radiologist. Despite the advent of computed tomography and magnetic resonance imaging, conventional polydirectional tomography remains an important tool in the evaluation of vertebral body autografts. Trispiral or hypocycloidal tomography plays a valuable role in the assessment of bone graft fusion and possible complications, especially in the presence of metallic fixation devices. We present our imaging experience derived from 375 patients with cervical, thoracic, or lumbar anterior spinal fusion. True graft complications occurred in 27 patients (7%) and consisted of fracture (4%), malpositioning (3%), and infection (<1%).     

Symptoms of contruction workers exposed to whole body vibration and local vibration

Summary To study the effects of construction machinery operation on subjective symptoms, a questionnaire survey was caried out among construction machinery operators by a self-reporting method. Subjects were 184 power shovel operators, 127 bulldozer operators, 44 forklift operators as operator groups, and 44 office workers as a control. Their ages were in a range of 30–49 years. The questionnaire contained 20 symptoms referring to fatigue, digestive problems, and upper or lower limbs or back problems. The prevalence rate and symptom characteristics were examined. The dominant symptoms of the operator groups were stiff shoulder, low back pain, and stomack symptoms. The prevalence rate of low back pain was significantly different between forklift operators and controls. No significant differences were found in the symptoms of upper limbs and fingers between operator groups and controls. The prevalence of Raynaud's phenomenon was 0.5%–2.3% in the operator groups and 2.3% in the control group.     

Effect of compressive follower preload on the flexion-extension response of the human lumbar spine.

Traditional experimental methods are unable to study the kinematics of whole lumbar spine specimens under physiologic compressive preloads because the spine without active musculature buckles under just 120 N of vertical load. However, the lumbar spine can support a compressive load of physiologic magnitude (up to 1200 N) without collapsing if the load is applied along a follower load path. This study tested the hypothesis that the load-displacement response of the lumbar spine in flexion-extension is affected by the magnitude of the follower preload and the follower preload path. Twenty-one fresh human cadaveric lumbar spines were tested in flexion-extension under increasing compressive follower preload applied along two distinctly different optimized preload paths. The first (neutral) preload path was considered optimum if the specimen underwent the least angular change in its lordosis when the full range of preload (0-1200 N) was applied in its neutral posture. The second (flexed) preload path was optimized for an intermediate specimen posture between neutral and full flexion. A twofold increase in flexion stiffness occurred around the neutral posture as the preload was increased from 0 to 1200 N. The preload magnitude (400 N and larger) significantly affected the range of motion (ROM), with a 25% decrease at 1200 N preload applied along the neutral path. When the preload was applied along a path optimized for an intermediate forward-flexed posture, only a 15% decrease in ROM occurred at 1200 N. The results demonstrate that whole lumbar spine specimens can be subjected to compressive follower preloads of in vivo magnitudes while allowing physiologic mobility under flexion-extension moments. The optimized follower preload provides a method to simulate the resultant vector of the muscles that allow the spine to support physiologic compressive loads induced during flexion-extension activities.     

Minimally invasive spinal surgery

Minimally invasive surgery offers quicker recovery and less morbidity for our patients through smaller surgical wounds and less tissue trauma. Although minimally invasive surgery has progressed in other fields of surgery for many years, spine surgeons have not previously embraced this philosophy for the various reasons discussed. However, minimally invasive spinal surgery has gained much interest in recent years. With the advent of new instrumentation, technology, and techniques, the promise of minimally invasive surgery in the spinal arena has become a reality. With the use of the microscope, navigational tools, newly developed canula for retraction, and image-guided percutenous pedicle screw systems, we can accomplish the same surgical procedures as currently used through smaller wounds and with greater precision. Nevertheless, all new technology does offer us an initial challenge of steep learning curves. Minimally invasive should not equate to minimal and inadequate treatment for our patients. Furthermore, careful analysis of this new technique is underway to assess its true advantages as compared with our current and proven techniques.