Subdental synchondrosis and anatomy of the axis in aging: a histomorphometric study on 30 autopsy cases

During skeletal development the two ossification centers of the odontoid process are separated from the corpus of the axis by a subdental synchondrosis. This synchondrosis is thought to close and disappear spontaneously in adolescence although this has never been studied in detail. The basis of the dens is of clinical relevance as type II dens fractures are located here. To characterize the morphological architecture of the axis with particular attention to the subdental synchondrosis, the complete axis was harvested from thirty age-matched and gender-matched patients of the three different age groups at autopsy. The subdental synchondrosis and the bone structure of the dens, the basis of the dens and the body of C2 were analyzed by radiography, histology and quantitative histomorphometry. At the macroscopic level the persistency of the subdental synchondrosis in the adult cervical spine was detected in 87% (26 of 30) of the specimens. Histomorphometry revealed a residual disc blastema with an average size of 25.8% of the sagittal depth of the basis of the dens at this level. Bony integration of the synchondrosis was poor throughout all ages. Histologically a cartilaginous matrix composition of the subdental synchondrosis persisted throughout all groups. The trabecular microarchitecture demonstrated a significant reduction of bone volume and trabecular number as well as an increased trabecular separation within the basis of the dens as compared to the corpus or the dens of C2. This histomorphometric data regarding a poor integration of the synchondrosis into the trabecular network and the reduced bone mass within the basis of the dens might offer a previously underestimated explanation for the occurrence of type II dens fractures and their association with pseudoarthrosis, respectively.Matthias Gebauer and Christian Lohse contributed equally to this study and therefore share first authorship.     

Salvage of a failed valgus osteotomy for non-union of an unstable pertrochanteric fracture

Salvage of a failed valgus osteotomy for nonunion of an unstable pertrochanteric fracture is reported. A valgus intertrochanteric osteotomy was performed for a failed sliding hip screw fixation of an unstable pertrochanteric fracture at another institution. Four months following osteotomy, the fracture was still un-united with two distal screws of the hip plate broken and a coxa vara deformity. Reconstruction was performed with a nine-hole 95° angle blade plate and cancellous bone graft, because the insufficient fixation of the distal fragment was considered to be the main reason for failure. The osteotomy was healed at six months post-surgery and the patient reported complete resolution of symptoms. Intertrochanteric valgus osteotomy is an effective procedure for mal-union and non-union of pertrochanteric fracture but stable fixation is required for a good result. The blade of the angle plate offers good purchase of the proximal fragment and secures it under rotational and bending stresses. We recommend that distal fragments should be fixed with at least seven cortices for this type of osteotomy.     

经皮椎弓根技术治疗胸腰椎骨折的临床探讨

目的:探讨微创经皮椎弓根螺钉内固定手术治疗胸腰椎骨折的可行性及其疗效。方法:20例胸腰椎骨折病例,男13例,女7例;年龄28~65岁,平均48·2岁。其中16例损伤平面以下无神经功能损害、无双下肢和大小便障碍;4例有不同程度的脊髓损伤,按Frankel分级:C级1例,D级3例。在C形臂X线的定位下确定需要固定的椎弓根根部,做4个1·5cm长的切口,固定与复位均在4个小切口内完成。结果:所有病例均获随访,时间9~18个月,平均15个月。术后患者椎体高度均有不同程度恢复,椎体后凸畸形获得不同程度矫正。手术时间约1·5h,出血量约80ml。结论:微创经皮椎弓根螺钉内固定手术操作简便、安全可靠,具有创伤小、出血少、疼痛轻、恢复快、住院时间短等优点。     

AO钢板内固定治疗跟骨骨折

目的 探讨复杂跟骨骨折治疗方法及AO钢板内固定价值.方法 应用AO钢板治疗累及距下关节的跟骨骨折24例,术中注意关节面复位和Bohler角的恢复.结果 24例病人经12～24个月随访,按照Fernandez评定标准:24例跟骨SandersⅡ-Ⅳ型骨折病人有18足评为优良.结论 距下关节面的复位和Bohler角的恢复,牢固的内固定和术后足够长时间的负重限制是成功的关键.     

空心螺钉治疗股骨颈骨折术后并发症的分析

目的探讨影响空心螺钉治疗股骨颈骨折术后早期并发症及中晚期股骨头缺血性坏死的因素。方法对1994年1月～2004年1月间应用空心螺钉治疗的116例股骨颈骨折患者进行回顾性总结,将患者性别、年龄、骨折类型、骨折复位情况、外伤至手术时间与骨折术后早期并发症及中晚期股骨头缺血性坏死间的关系进行统计学分析。结果116例患者获平均(3．2±2．5)年(1～11年)随访。术后早期并发症包括：骨折内固定失败6例,骨折周围再骨折2例,感染2例,下肢深静脉血栓6例。年龄是引起骨折术后早期并发症的主要因素之一；骨折术后早期并发症还与骨质情况及内固定技术有关。本组16例出现股骨头缺血性坏死,其坏死率为13．8%。造成股骨头缺血性坏死的因素主要是骨折类型,其次为骨折复位情况。结论①年龄大于60岁的患者股骨颈骨折术后早期并发症相对多。②对于骨折移位严重的高龄患者,建议行人工关节置换术。③内固定术应尽可能解剖复位、坚强牢靠,以减少术后股骨头缺血性坏死的发生。     

下肢复杂骨折交锁髓内钉治疗粉碎骨折螺钉辅助固定的意义

[目的]探索在交锁髓内钉治疗下肢复杂骨折中粉碎骨折块辅助固定的意义。[方法]下肢复杂骨折78例根据AO分型均为C型骨折，通过交锁髓内钉内固定，辅以拉力螺钉固定。[结果]术后摄片骨折及骨折块达解剖或功能复位，随诊6～24个月，优良率为94．88％（74／78例）。[结论]四肢复杂骨折治疗中，粉碎骨折块的螺钉辅助固定能够加强交锁髓内钉的稳定性，减少断钉、断棒现象，有利于骨折愈合。     

鼻内镜下诊治鼻中隔骨折

目的:探讨鼻窦内镜对鼻中隔骨折的诊治。方法:45患者就诊时均行鼻窦内镜检查、鼻骨侧位片和鼻窦CT检查。均在鼻窦内镜下行鼻骨骨折复位术和鼻中隔成形术。结果:1例患者术后鼻外形改善不明显外,其余均得到治愈。结论:鼻窦内镜检查并酌行CT扫描是确诊鼻中隔骨折的主要手段,鼻骨骨折整复术同时可行鼻中隔成形术。     

超高龄老人髋部骨折的手术治疗

目的　探讨 80岁以上老年人髋部骨折围手术期处理经验。方法　对 4 6例 80岁以上老年人髋部骨折手术治疗方法及结果进行回顾性总结。结果　 4 6例患者均安全度过围手术期 ,手术优良率 89 7%。结论　对高龄患者要有充分认识和准备 ,大部分患者能接受手术治疗并获得优良效果     

经皮椎体后凸成形术治疗胸腰椎骨折的临床疗效观察

目的：探讨经皮椎体后凸成形术治疗胸腰段椎体压缩性骨折的临床疗效.方法：2003年6月～2005年9月收治74例胸腰段椎体压缩性骨折患者,根据手术方法不同分为A组（椎体后凸成形术组,24例）和B组（椎弓根螺钉固定组,50例）.比较两组术前术后椎体前缘、中线、后缘高度变化,疼痛视觉模拟评分（visual analogue pain scale,VAS）,手术时间,出血量等方面的差异.结果：两组对椎体高度的恢复比较无统计学意义,A组的手术时间和出血量较B组少,差异有统计学意义（P＜0.01）,术后VAS评分A组较B组低（P＜0.01）.结论：经皮椎体后凸成形术与椎弓根螺钉系统治疗椎体压缩性骨折具有相似效果,但经皮椎体后凸成形术具有创伤小、手术时间短、出血量少等微创优点.