胸腰椎骨折椎弓根内固定断裂与植骨融合方式的相关性分析

[目的]探讨胸腰椎骨折椎弓根螺钉内固定系统内固定术后,椎弓根螺钉断裂与植骨融合方式之间的关系,以探讨胸腰椎骨折植骨融合的最佳方式。[方法]回顾性研究1995年5月~2005年12月本院脊柱外科收治的胸腰椎骨折病人197例,其中A组单纯内固定(不植骨)患者14例,B组“H”形椎板植骨21例,C组横突间植骨67例,D组椎间、椎内联合横突间植骨95例。[结果]术后随访6~32个月,内固定断裂12例,其中A组4例,B组3例,C组5例,D组0例,4组中D组内固定断裂率显著低于其他3组(P<0.05)。[结论]椎间、椎体内联合横突间植骨重建脊柱三柱的稳定性,符合人体生物力学原理,能有效降低内固定断裂的发生。     

Influence of the design of the prosthesis on the outcome after hemiarthroplasty of the shoulder in displaced fractures of the head of the humerus

We reviewed 39 patients with displaced three- and four-part fractures of the humerus. In 21 patients (group A) we had used an anatomical prosthesis for the humeral head and in 18 (group B) an implant designed for fractures. When followed up at a mean of 29.3 months after surgery the overall Constant score was 51.9 points; in group A it was 51.5 and in group B 52.4 points. The subjective satisfaction of the patients was assessed using a numerical rating scale and was similar in both groups. In group A complete healing of the tuberosities was found in 29% and 50% in group B. Partial integration was seen in 29% of group A and in only one patient in group B, while resorption was noted in 43% of group A and 44% of group B. The functional outcome was significantly better in patients with complete or partial healing of the tuberosities (p=0.022). The specific trauma prosthesis did not lead to better healing of the tuberosities. The difference in clinical outcome obtained by the two designs did not reach statistical significance.     

Radiographic assessment of the relative lengths of the bones of the fingers of the human hand

The study assessed whether a relationship existed between the lengths of the phalanges of the fingers of the hand. The centres of rotation of the joints in each finger were determined by dissection of cadaveric hands. Using these data, the distances between the joint centres was determined on anteroposterior hand X-rays taken for clinical purposes. The study has shown that, for all the fingers, there is a ratio of 1 for the distance between the metacarpophalangeal and proximal interphalangeal joint and the distance between the proximal interphalangeal joint and the finger tip. The ratio for the distances between the interphalangeal joints and the distal joint and the tip approximates to 1.3 for the index, middle and ring fingers and to 1.0 for the little finger. No evidence was found to support Littler's hypothesis that the interarticular distances of the finger follow the Fibonacci sequence.     

Fractures of the shafts of the phalanges of the hand.

Fractures of the shafts of the phalanges are common and often disabling. Little detailed information is available as to the results of treatment, against which new methods of treatment may be compared. Thirty-nine comminuted fractures and 109 which were not comminuted were followed-up and their results are presented in detail. In both groups only about 57% obtained satisfactory results. Possible methods of improving these are discussed and the importance of accurate reduction of non comminuted fractures is emphasised.     

Prevention of the development of the typical dislocation of the hip

Applying a diaper and baby clothing without changing the naturally flexed leg requires education of mothers and nurses. Retaining the flexed position which is present from the very beginning of postnatal life, markedly reduces the incidence of click sign. A program on neonatal diapering, clothing, and general care, reduced the incidence of congenital dislocation of the hip in 3 to 7 months old infants in a sample population of 200,000.     

Analysis of the impact of the course of hydration on the mechanical properties of the annulus fibrosus of the intervertebral disc

Purpose

The aim of this study was to determine the impact of free hydration on the mechanical parameters of the annulus fibrosus (AF) of the intervertebral disc (IVD), determined in a standard manner. Attention was also given to the hydration occurring in real time and geometric changes resulting from swelling of the AF.

Methods

Uniaxial tensile tests of multilayer samples of the AF with bone attachment were performed for two groups: samples subjected to 30 min of hydration prior to the mechanical test, and control samples, which were not subjected to additional hydration.

Results

As a result of hydration, the values of both the failure stress (σ _UTS) and the tensile modulus (E) were lower than in the control group. A decrease in these values was observed for the AF from both the anterior and posterior parts of the IVD.

Conclusions

The tests showed a significant dependence of the determined mechanical parameters on the cross-sectional area. The larger the cross-sectional area, the lower the obtained value of stress. By contrast, the value of the stiffness coefficient is independent of the cross-sectional area. The differences in mechanical parameters are related mainly to water absorption into structures of the AF during hydration. This is confirmed by microscopic analysis of geometric dimensions of the AF during hydration conducted in real time. The greatest changes occurred in the radial direction, where the thickness increased by 2.05 mm, while in the axial direction the main change concerned an increase in height by 0.69 mm. There were negligible changes in the circumferential direction.

     

Distribution of the vascular network of the adenohypophysis of the rat

From various experiments it has been suggested that the blood flow to the different parts of the adenohypophysis is not the same. By developing the peroxidase activity of the red and white blood cells we have obtained a satisfactory image of the distribution of the intrahypophysial vessels, which indicate that the organization and distribution of these vessels varies from one portion to another in the pars distalis. On the lateral portion of the gland vascular routes are irregular, whilst in the media zone they run in a sagittal plane. Between the above-mentioned portions, on either side of the edge of the pars intermedia, a rich vascular network extending along the dorsal limit, which is fed by the long portal vessels and by numerous smaller vessels from the ventral vascular chain of the pars intermedia and neural lobe, is observed.