空心加压螺纹钉治疗股骨颈骨折

2001～2003年,笔者用空心加压螺纹钉治疗股骨颈骨折21例,效果满意。     

Femoral neck fracture in end-stage renal disease treated with osteosynthesis

BackgroundTreatment of femoral neck fracture is well documented in the literature. Femoral neck fractures in patients aged < 65 years are generally treated using closed reduction and internal fixation, while hemiarthroplasty is the treatment of choice for patients > 65 years. In specific populations, such as patients with end-stage renal disease (ESRD), this protocol is usually observed. However, unsatisfactory results and a large number of complications have been reported. It is questionable whether this protocol is the appropriate treatment and it may require modification for use in ESRD patients.Materials and methodsThe results of this study are in regard to the treatment of a consecutive series of 20 patients with femoral neck fractures and ESRD over a 7-year period. All of the patients were treated using closed reduction and internal fixation.ResultsEight of 13 (61.5%) patients developed nonunion (of which 5 were classified as displaced fractures). Six of these eight patients were subsequently treated with hemiarthroplasty (75%). Five of these 13 patients(38.4%) achieved union; all of these were classified as nondisplaced fractures. In patients < 70 years, five of 11 patients demonstrated nonunion (45.5%), of which all were classified as displaced fractures. The mortality rate of this series was 33.3% (5 of 15 patients).ConclusionWe determined that a femoral neck fracture in an ESRD patient is a unique case and should be treated differently from general treatment protocols. It is suggested that regardless of patient age,nondisplaced fractures should be treated with osteosynthesis, while hemiarthroplasty is a better treatment for displaced fractures.     

Vertebral trabecular bone microscopic tissue elastic modulus and hardness do not change in ovariectomized rats.

Ovariectomized rats have been used extensively and have received substantial acceptance as animal models for postmenopausal osteoporosis. However, little is known about the microscopic tissue properties of rat vertebral bone, especially during osteoporosis caused by estrogen depletion. This study applied a new nanoindentation technique to quantify the microscopic mechanical properties of vertebral trabecular bone tissue in ovariectomized rats. Seventeen-week-old Sprague-Dawley rats underwent an ovariectomy. After death at 37 weeks, the fraction of the trabecular bone area of the lumbar vertebrae (L4) was measured with scanning electron microscopy and the elastic modulus and hardness were determined with the nanoindentation technique. The bone area fraction was reduced significantly after the ovariectomy. However, the elastic modulus and hardness did not change significantly at the microscopic level. The results indicate that estrogen-dependent osteoporosis in rats manifests in a loss of bone mass whereas the elastic and hardness properties of the surviving bone tissue remain relatively unchanged.     

Effects of risedronate on trabecular microstructure and biomechanical properties in ovariectomized rat tibia

We determined the effect of risedronate on the trabecular microstructure of ovariectomized rat tibiae, using micro-computed tomography, in order to investigate how changes in microstructure contribute to biomechanical properties. Fifty 18-week-old rats underwent sham operation (n=10) or ovariectomy (OVX) (n=40). The OVX rats were further divided into four groups (n=10 for each group) and treated with risedronate at doses of 0, 0.1, 0.5 or 2.5 mg/kg for 9 months. OVX caused deterioration of three-dimensional trabecular microstructure, notably structure model index (SMI) and connectivity density, while treatment of OVX rats with risedronate at 0.5 and 2.5 mg/kg improved those deleterious microstructural changes. Biomechanical property, as assessed by finite element analysis (FEA), correlated significantly with trabecular bone volume fraction (BV/TV), and the correlation further increased substantially when microstructural parameters were added, especially SMI and connectivity density, with risedronate therapy. Thus, it is suggested that, in addition to increasing bone mass, risedronate improves biomechanical property by maintaining a plate-like structure as well as connectivity of trabeculae.     

Femoral neck fractures. 121 cases treated by Knowles pinning

The femoral neck fracture remains one of the unsolved fractures. It is a fracture with a high incidence of nonunion and avascular necrosis. One hundred twenty-one mostly young adult patients with femoral neck fractures were treated by Knowles pins internal fixation. Patients were observed for an average of 32 months following surgery. Union occurred in all Garden Stage I and II undisplaced fractures, and the incidence of nonunion was 14% in Garden Stage III and IV displaced fractures. The incidence of avascular necrosis was 5.9% in undisplaced fractures and 34.5% in displaced fractures. There was no significant difference in avascular necrosis rates among age groups. Nonunion and avascular necrosis occurred mainly in displaced fractures. Knowles pinning offers the advantages of few technical failures, early weight bearing, high union rate, and low complication rate.     

去卵巢大鼠胫骨和椎骨松质骨微结构的显微CT分析

目的观察大鼠去卵巢后,椎骨和胫骨松质骨微结构变化。方法 50只7月龄SD大鼠随机分为基线组,去卵巢组和假手术组。基线组在试验开始时处死,去卵巢组和假手术组分别在去卵巢后3周、15周各处死。分离大鼠第五腰椎和左侧胫骨,用显微CT(microCT)对椎骨及胫骨骨骺端松质骨进行扫描,对其微结构定量分析。结果去卵巢第3周和第15周,OVX组胫骨骨体积分数(BV/TV)、骨小梁数量(Tb.N)和连接密度(Conn.D)均显著性小于SHAM组,骨小梁间隔(Tb.Sp)和结构模型指数(SMI)均明显大于SHAM组。去卵巢第3周,OVX组椎骨BV/TV显著性小于SHAM组,SMI明显大于SHAM组,至第15周,OVX、SHAM两组间椎骨的微结构差异与胫骨相同。纵向观察,OVX组胫骨随着时间变化出现BV/TV和Conn.D进行性减少,Tb.Sp进行性增加,面积骨密度(tBMD)和骨小梁厚度(Tb.Th)在第3到15周分别出现下降和增加。OVX组椎骨BV/TV在去卵巢3周内下降,Conn.D和Tb.Sp在3到15周内分别出现减少和增加。胫骨和椎骨的Tb.N随时间均进行性减少,SMI均在3周内增加。结论雌激素缺乏时大鼠松质骨微结构改变呈现出区域性,胫骨松质骨微结构丢失的发生比椎骨早,更为显著。     

肱骨颈型钢板治疗儿童股骨转子部骨折

目的探讨儿童不稳定性股骨转子部骨折的治疗方法和疗效。方法1998年6月～2005年6月采用肱骨颈型钢板内固定治疗9例儿童不稳定性股骨转子部骨折患者,其中转子间骨折2例,转子下骨折7例。结果9例患者术后获0．5～7．0年(平均3．6年)随访。所有患者均于11周内获骨性愈合。股骨无髋内外翻、股骨头缺血性坏死及股骨头骺滑脱等并发症发生。所有患者髋关节活动范围均恢复至正常范围。结论肱骨颈型钢板内固定治疗儿童转子部骨折方法简单,固定准确、稳定,不损伤骨骺,可尽早行功能锻炼,愈合快,并发症少。     

股骨颈骨折病人的股骨头样本结构的Micro-CT评估

[目的]利用Micro-CT（Micro-computed Tomography）对正常人和老年股骨颈骨折病人的股骨头松质骨样本进行三维评价和比较。[方法]对6位正常人（正常组，27～36岁）和9位老年股骨颈骨折病人（骨折组，70～78岁）的股骨头松质骨样本进行DEXA检查，获取骨矿物密度数据。行Micro-CT扫描，得到松质骨小梁空间结构的计算机三维图形，并进行三维计量。[结果]与正常组相比，股骨颈骨折病人股骨头负重区样本的骨小梁结构在骨体积分数BV／TV、骨表面积体积比BS／TV、骨小梁厚度Tb.Th、骨小梁间隙Tb．Sp存在显著差异（P〈0．01），而骨小梁数目Tb．N、结构模型指数SMI和骨小梁模型因子Tb．Pf之间无统计学差别。骨密度检测两组没有显著性差异（P〉0．05）。[结论]股骨头松质骨的空间结构会因年龄增大而发生改变。     

Usefulness of MRI volumetric evaluation in patients with squamous cell cancer of the head and neck treated with neoadjuvant chemotherapy

BACKGROUND: The purpose was to evaluate the efficacy of tumor volumetry on MRI as predictive of response to treatment with induction chemotherapy, comparing the results with endoscopy. METHODS: Fifty patients with advanced squamous cell carcinoma of the head and neck (SSCHN) who underwent MRI volumetry before and after neoadjuvant chemotherapy consisting of docetaxel, cisplatin, and 5-fluorouracil (TPF) were included in this study. The tumor volume was calculated by a slice-by-slice evaluation. With the standard software of a workstation, the area of the tumor was measured slice by slice using manual segmentation. To evaluate the efficacy of MRI volumetry, pretreatment volume was compared with pretreatment remission status as evaluated with endoscopy. RESULTS: Forty-five (90%) patients demonstrated a tumor downstaging after chemotherapy. Fourteen (28%) patients showed a complete histologic remission (CR), 31 (62%) patients showed a partial remission (PR). Pretreatment tumor volume was significantly different between patients whose tumor completely responded (CR) and those whose tumor did not completely respond or whose disease was stable or was progressive (p = .00023). We defined a threshold for the pretreatment tumor volume in patients with CR, which was equal to 29.71 cc. CONCLUSION: We propose that MRI tumor volume analyses can be a useful parameter to predict the response to neoadjuvant chemotherapy in SCCHN.     

Femoral neck fractures in young adults.

In 17 patients with femoral neck fractures who were between 15 and 40 years old the incidence of aseptic necrosis in patients followed more than 2 years was 18.7 per cent. The fracture was associated with other severe injuries in 40 per cent of the cases, probably reflecting the level of violence necessary to induce the fracture in young adults. Two of the 7 fractures treated with large-bore internal fixatives required secondary procedures to correct fracture displacement (this was not a complication with threaded devices). While the incidence of aseptic necrosis is no higher than that in other adult series, subsequent degenerative changes may supervene in many femoral neck fractures in this age group.     

前侧减压复位经皮空心钉内固定治疗青壮年股骨颈骨折

股骨颈骨折多发于老年人,近年来随着交通伤及坠落伤的增多,青壮年股骨颈骨折的发病率有上升的趋势.由于青壮年股骨颈骨质坚固,骨折往往是受到较大暴力所致,损伤严重,骨折端的严重错位容易导致局部血管的损伤,极易发生骨折不愈合及股骨头坏死,一直是骨科治疗的难点.     

A case of Albright's syndrome treated with calcitonin.

A 23-year-old woman with Albright's syndrome (polyostotic fibrous dysplasia of bone, precocious puberty and irregular cutaneous pigmentations) had sustained multiple fractures and was grossly disabled. Evaluation disclosed markedly raised serum alkaline phosphatases and a high urinary excretion of hydroxyproline, suggesting an accelerated bone turnover, while calcium metabolism was virtually undisturbed. During 12 months therapy with calcitonin, however, no apparent benefit was recorded and there was no evidence of any significant metabolic effects of the treatment. Initial discomfort with nausea and vomiting disappeared after dose reduction whereas diffuse bone and muscle pain, which gradually increased after a few months treatment, did not subside until after cessation of the therapy.     

Femoral structure and stiffness in patients with femoral neck fracture.

Bone morphological characteristics may relate to the risk of hip fracture. We applied finite element modeling to radiologic data for two groups of women in vivo to address two questions: (a) Do individuals who have just sustained a femoral neck fracture exhibit reduced three‐dimensional structural stiffness? and (b) Are victims of hip fracture disproportionately more susceptible to loads sustained in a fall than to stance‐type loads? Ten white women (age: 64–76 years) who had just sustained a femoral neck fracture and 18 female volunteers (age: 65–76 years), matched as groups for race, age, and body mass index, were evaluated, From quantitative computed tomography scans, femoral morphometric and volumetric cancellous density measurements were obtained and a finite element model was constructed. Two load conditions were simulated: single‐stance phase and lateral fall. Global stiffness values were determined for each model. The cancellous bone density was significantly lower at the femoral neck and the femoral neck and head diameters were significantly larger in the women in the fracture group than in those in the control group. The stiffness of the proximal femur did not differ significantly between the groups for either load condition. An apparently linear relationship was found for stiffness at stance load compared with stiffness at fall load (r = 0.84, p < 0.001), and slopes did not differ significantly between the groups. Although cancellous density was reduced at the fracture site in patients with femoral neck fractures, this did not result in a reduction in the predicted bone stiffness. Previous studies have established a very strong relationship between the stiffness and strength of bone. Since these modeling methods were thoroughly validated ex vivo, we conclude that although decreased bone density at the femoral neck may predict where fracture initiates, the risk of hip fracture per se may be more strongly dependent on issues such as the risk of falling and fall biomechanics than on the structural characteristics of bone.     

Intratrabecular tunneling increases trabecular number throughout the skeleton of ovariectomized rhesus monkeys treated with parathyroid hormone 1-84

Daily treatment of ovariectomized (OVX) adult rhesus monkeys with human parathyroid hormone (PTH) 1-84 for 16 months increases trabecular bone volume (BV/TV), number (Tb.N) and connectivity at lumbar vertebra-3 (L3) and thoracic vertebra-10. We proposed that the increased Tb.N and connectivity was achieved by stimulation of intratrabecular tunneling. Using histomorphometry to determine frequency of events, we have now quantified intratrabecular tunneling at L3 and extended it to investigate the effects of PTH(1-84) treatment on trabecular bone at the proximal femur, distal radius and iliac crest of these animals. At L3, tunneling frequency was low in control sham and OVX animals ( approximately 0.05/mm(2)) but increased significantly in PTH(1-84)-treated animals (0.27, 0.49 and 0.95/mm(2) with the 5, 10 and 25 microg/kg doses, respectively). Very similar tunneling frequencies were observed at all skeletal sites in all groups. Iliac crest biopsies were also collected at baseline and after 6 months of treatment and showed significant time- and dose-related increases in tunnels. Although the pattern and magnitude of response varied slightly from site to site, PTH(1-84) treatment significantly increased Tb.N, as well as BV/TV and bone formation rate at all skeletal sites. A modest but statistically significant increase in trabecular thickness occurred only at the iliac crest. In summary, intratrabecular tunneling is rare in control monkeys, but increased substantially with PTH(1-84) treatment. This phenomenon provides a plausible explanation for the PTH(1-84)-induced increase in Tb.N observed in OVX monkeys. Moreover, these analyses allowed a comparison of the effects PTH(1-84) treatment on trabecular bone at multiple locations.     

Bone loss dynamics result in trabecular alignment in aging and ovariectomized rats.

Because of the destructive nature of techniques used to measure bone morphometry, studies of architectural changes and bone loss have utilized cross-sectional study designs, with all its inherent limitations in nuances. Here, the results of a longitudinal study using in vivo micro-CT are presented elucidating the dynamics of bone loss and architectural adaptation in rat models of aging and postmenopausal bone loss. Using 3-D methodology, we observed the changes in bone architecture in the proximal tibia of normally aging and ovariectomized rats for 54 weeks. Spatial patterns in bone resorption were observed that were similar for both groups. Remaining trabeculae increased in thickness or were remodeled into new trabecular structures, especially in the ovariectomized animals. The combination of bone loss and bone formation resulted in alignment of trabeculae across the growth plate. Cortical modeling that was associated with growth continued after cessation of longitudinal growth in the ovariectomized animals, resulting in shape changes of the proximal tibia. The organized nature of the changes in bone architecture that occurred after ovariectomy and the high similarity with the changes observed in the normally aging animals, suggest that estrogen depletion resulted in an acceleration of a normal bone adaptation process. The observed aligning of trabeculae suggests regulation through mechanical loading.     

Effect of vitamin K2 on three-dimensional trabecular microarchitecture in ovariectomized rats.

Menatetrenone, a vitamin K2 with four isoprene units, has been reported to improve osteoporotic bone loss. The purpose of this investigation was to clarify the effect of menatetrenone on the three-dimensional (3D) trabecular microarchitecture in ovariectomized (OVX) rats by using microcomputed tomography (MCT). Forty-two 13-week-old female rats were used and divided into four groups: the OVX (OVX + MK-4) group treated with menatetrenone, the (OVX untreated) group, the sham-operated (Sham + MK-4) group treated with menatetrenone, and the sham-operated group not treated with menatetrenone (Sham untreated) group. OVX rats were fed a calcium-deficient diet. Menatetrenone treatment was begun just after the ovariectomy, and the mean menatetrenone oral intake over the 8-week period was adjusted to 30 mg/kg BW per day. The proximal metaphyseal region of the right tibia was evaluated by dual X-ray absorptiometry (DXA) and MCT. A parametric analysis of the reconstructed trabecular volume was carried out using bone volume fractions, the fractal dimension calculated by the 3D box-counting method, and the connectivity density as determined by topological analysis. Menatetrenone significantly increased the trabecular bone volume, fractal dimension, and connectivity in the OVX + MK-4 group compared with the OVX-untreated group (p < 0.01). Our results suggest that an 8-week administration of menatetrenone protects against the loss of trabecular bone volume and its connectivity when treatment is begun just after the ovariectomy. Despite this apparent protection, it remains unknown whether it is possible to reestablish trabecular connectivity if therapeutic intervention occurs after the trabecular connectivity has been lost.     

Age- and gender-dependent changes in three-dimensional microstructure of cortical and trabecular bone at the human femoral neck

Summary  

We investigated age- and gender-related variation of both cortical and trabecular microstructure in human femoral neck. We found that age-related change of cortical porosity is more noticeable than that of trabecular parameter. Our data may help to gain more insight into the potential mechanism of osteoporotic femoral neck fractures.