The postnatal development of the insertions of the medial collateral ligament in the rat knee

Bone soft tissue remodelling at the femoral and tibial insertions of the medial collateral ligament (MCL) of the rat knee was monitored at regular intervals from birth to 120 days of age in 40 Sprague Dawley rats. At birth the femoral insertion originated from the perichondrium of the epiphysis. By day 8 the perichondrium within the insertion had turned into fibrocartilage. Secondary ossification of the femoral epiphysis had progressed in the region near to the insertion site by day 15. The epiphyseal cartilage was entirely replaced by bone by day 40 except for the fibrocartilage within the insertion. After that stage, no qualitative change in zonal insertion characteristics was observed, but only increase in size and decrease in cellularity. At birth, the tibial ligament inserted onto the thin cortical bone of the metaphysis via periosteum. At day 8, osteoclasts started to resorb the thin cortical bone at the ligament insertion, thus forming a metaphyseal depression between days 10 and 20. From days 20 to 120, the insertion remained qualitatively unchanged, showing three zones, the ligament, periosteum, and metaphyseal trabecular bone. The deep periosteal layer showed osteoclastic activity in the proximal part and osteoblastic activity in the distal part. The migration mechanism of the ligament insertion during growth seems to be caused by this growth-related osteoclastic resorption of the proximal metaphyseal bone and by simultaneous osteogenic activity, which successively cements the distal part of the ligament to bone. The persistence of the periosteal layer and the metaphyseal depression for up to 120 days may be regarded as a sign of continuing growth in this animal model. This is the first investigation showing that the formation of the metaphyseal depression is a purely postnatal event, and suggests that this process might be initiated by the change in mode of growth and joint biomechanics after birth, enabling ligament development and migration in a growing and increasingly loaded weight-bearing joint. The mainly resorptive process, which takes place during development of the tibial MCL insertion, may account for the tensile failure of this ligament that commonly occurs at this site during growth. The pronounced morphological differences between the chondral femoral and the periosteal tibial attachment of the adult MCL are apparently caused by the different postnatal developmental processes at epiphyses and metaphyses.Presented in part at the meeting of the Orthopaedic Research Society, Orlando, Florida, 13–16 February, 1995     

Epiphyseal and physeal cartilage vascularization: A light microscopic and tritiated thymidine autoradiographic study of cartilage canals in newborn and young postnatal rabbit bone

The vascular pattern of newborn and early postnatal epiphyseal and physeal cartilage is integral to long bone development and differs from later postnatal patterns. In the present study, we supplement light microscopic histology with tritiated thymidine autoradiography to help assess the position of cartilage canals and the dynamics of cartilage vascularity in relation to growth. Tritiated thymidine labeling studies to assess cell proliferation activity were done by using 2 μc/g body weight intraperitoneal injections into newborn and 3-, 4-, and 7-day-old New Zealand white rabbits that were killed 1 hr after the injection. Proximal humeral, distal femoral, and third metatarsal epiphyses were assessed by routine histology and serial section autoradiography. Cartilage canals were seen in each epiphysis. Transphyseal vessels were seen in each epiphysis continuous from the epiphysis to the metaphysis or were present within the physis traversing the proliferating and hypertrophic cell zones. Histologic sections showed vessels from the perichondrium continuous with those of the epiphyseal cartilage canals at proximal humeral, distal femoral, and metatarsal epiphyses. Serial sections showed vascular buds and connective tissue cells lying in indentations at the periphery of and present within the epiphyseal cartilage. Autoradiographic studies showed extensive labeling of vessel wall cells and surrounding connective tissue cells of the cartilage canals (a) within the epiphyseal cartilage, (b) traversing the physis, and (c) within the epiphyseal cartilage but continuous with the perichondrial vessels. The labeling was always far more extensive than in the surrounding chondrocytes and was always present throughout the entire extent of the canals. In conclusion, the cell labeling activity strongly supports an active dynamic phenomenon underlying the vascularization of epiphyseal and physeal cartilage. Anat. Rec. 252:140–148, 1998. © 1998 Wiley-Liss, Inc.     

Thinner tuberosity osteotomy is more resistant to axial load in medial open-wedge distal tuberosity proximal tibial osteotomy: A biomechanical study

BackgroundThe purpose of this study was to investigate axial load resistance of the tibia depending on the thickness of tibial tuberosity osteotomy in medial open-wedge distal tuberosity proximal tibial osteotomy (OWDTO). The hypothesis is that a thin tibial tuberosity osteotomy shows high axial load resistance of the tibia.MethodsThe OWDTO model was constructed from imitation bones of the tibia. Distal tibial tuberosity osteotomy was performed with thicknesses of 7, 14, and 21 mm (n = 5 for each group). Cyclic axial-load fatigue tests were performed to investigate the strain at five measurement points on the OWDTO model. An axial-load failure test was also performed to investigate the maximum strain for failure.ResultsThe 7-mm OWDTO model showed a significantly lower stain range than the 14-mm model at the middle part of the lateral hinge (P = 0.0263, mean difference: −852.6 με), posterior part (P = 0.0465, mean difference: −1040.0 με), posterior tibial cortex (P < 0.0001, mean difference: −583.4 με), and plate (P = 0.0029, mean difference: −121.6 με). There were no significant differences in the strain at the tibial tuberosity between the groups. The axial load for complete failure was significantly higher in the 7-mm model than in the 21-mm model (P = 0.0010, mean difference: 2577.0 N). The failure points were at the lateral hinges.ConclusionsThinner distal tibial tuberosity osteotomy is more resistant to axial load and may be recommended for the prevention of tibial and lateral hinge fractures after OWDTO.     

Epiphyseal osteosarcoma: distinguishing features from clear cell chondrosarcoma, chondroblastoma, and epiphyseal enchondroma

In a retrospective radiologic and histologic study of 286 osteosarcomas in files of a metropolitan hospital, four patients (three men and one woman) with osteosarcomas confined to the epiphysis were identified. In this series, there were also 16 metaphyseal osteosarcomas that extended to the epiphysis with penetration through the cartilaginous growth plate, a structure that ordinarily resists tumor growth. All tumors occurred in the femoral condyle. Characteristically, all four patients had histories of knee joint pain, and three reported antecedent trauma. Radiologically, the tumors showed predominantly lytic features. Histologically, three of the tumors were osteoblastic in type, and one was mostly chondroblastic. Purely epiphyseal osteosarcoma has overlapping radiologic features with clear cell chondrosarcoma, epiphyseal chondroblastoma, and epiphyseal enchondroma. The epiphyseal osteosarcomas of the distal femur reported here were characterized by a history of symptoms localized to the knee joint itself as a consequence of their epiphyseal location and joint involvement. This is in contrast to the usual metaphyseal osteosarcomas, which present with lower thigh pain and swelling. Because osteosarcomas may present as lytic tumors confined to the epiphysis, they should be included in the differential diagnosis of such lesions.     

可吸收线治疗骨性锤状指远指间关节固定针位置的解剖研究

目的　通过测量末节手指的体表标记线与克氏针进针点的关系,为可吸收线捆扎固定撕脱骨块治疗骨性锤状指的远指间关节固定针进针点及角度、缝合线导引孔的位置提供解剖学依据。 方法　在16侧新鲜成人上肢标本的拇指、示指、中指、环指、小指各16根上模拟远侧指间关节的固定针（克氏针）固定,并测量进针点及进针角度。 结果　远侧指间关节伸0°位时,固定针宜从指体侧方进针,固定远侧指间关节的最佳进针点位于末节指骨基底部与指骨干交界处,进针角度与末节指骨中轴线成30°夹角,进针点到指远侧纹平面距离分别为：拇指13 mm、示指12 mm、中指13 mm、环指12 mm、小指11 mm。可吸收线导引孔最佳进针点在肌腱止点远端的指骨侧中线体表投影线上。 结论　固定针进针点以及导引孔位于上述各手指的位置时,既固定牢固、不损伤甲基质,也不影响撕脱骨片的复位。     

Development of the tibial tuberosity

The tibial tuberosity develops by a concomitant, and juxtaposed, outgrowth of hyaline cartilage and ingrowth of fibrovascular tissue. During the fetal period this hyaline cartilage outgrowth is progressively distally displaced to become situated adjacent to the anterior portion of the tibial metaphysis. About four to six months post-natally a growth plate develops under the tibial tuberosity. This growth plate shows structural adaptations that permit accommodation of large tensile stresses. The growth plate of the tibial tuberosity has three distinct regions — (a) a zone of endochondral bone formation, (b) a zone of intramembranous bone formation through fibrocartilage, and (c) a zone of intramembranous bone formation through fibrous tissue.     

Does the epiphyseal cartilage of the long bones have one or two ossification fronts?

Epiphyseal cartilage is hyaline cartilage tissue with a gelatinous texture, and it is responsible for the longitudinal growth of the long bones in birds and mammals. It is located between the epiphysis and the diaphysis. Epiphyseal cartilage also is called a growth plate or physis. It is protected by three bone components: the epiphysis, the bone bar of the perichondrial ring and the metaphysis. The epiphysis, which lies over the epiphyseal cartilage in the form a cupola, contains a juxtaposed bone plate that is near the epiphyseal cartilage and is in direct contact with the epiphyseal side of the epiphyseal cartilage. The germinal zone corresponds to a group of cells called chondrocytes. These chondrocytes belong to a group of chondral cells, which are distributed in rows and columns; this architecture is commonly known as a growth plate. The growth plate is responsible for endochondral bone growth. The aim of this study was to elucidate the causal relationship between the juxtaposed bone plate and epiphyseal cartilage in mammals. Our hypothesis is that cells from the germinal zone of the epiphyseal side of the epiphyseal cartilage are involved in forming a second ossification front that is responsible for the origin of the juxtaposed bone plate. We report the following: (a) The juxtaposed bone plate has a morphology and function that differs from that of the epiphyseal trabeculae; (b) on the epiphyseal edge of the epiphyseal cartilage, a new ossification front starts on the chondrocytes of the germinal area, which forms the juxtaposed bone plate. This ossification front is formed by chondrocytes from the germinal zone through a process of mineralisation and ossification, and (c) the process of mineralisation and ossification has a certain morphological analogy to the process of ossification in the metaphyseal cartilage of amphibians and differs from the endochondral ossification process in the metaphyseal side of the growth plate. The close relationship between the juxtaposed bone plate and the epiphyseal cartilage, in which the chondrocytes that migrate from the germinal area play an important role in the mineralisation and ossification process of the juxtaposed bone plate, supports the hypothesis of a new ossification front in the epiphyseal layer of the epiphyseal plate. This hypothesis has several implications: (a) epiphyseal cartilage is a morphological entity with two different ossification fronts and two different functions, (b) epiphyseal cartilage may be a morphological structure with three parts: perichondrial ring, metaphyseal ossification front or growth plate, and epiphyseal ossification front, (c) all disease (traumatic or dysplastic) that affects some of these parts can have an impact on the morphology of the epiphyseal region of the bone, (d) there is a certain analogy between metaphyseal cartilage in amphibians and mammalian epiphyseal cartilage, although the former is not responsible for bone growth, (e) comparative histological and anatomy studies are also warranted, to shed light on the phylogenetic study of epiphyseal cartilage throughout the changes that occur in the animal species.     

Development of the tibial tuberosity.

The tibial tuberosity develops by a concomitant, and juxtaposed, outgrowth of hyaline cartilage and ingrowth of fibrovascular tissue. During the fetal period this hyaline cartilage outgrowth is progressively distally displaced to become situated adjacent to the anterior portion of the tibial metaphysis. About four to six months post-natally a growth plate develops under the tibial tuberosity. This growth plate shows structural adaptations that permit accommodation of large tensile stresses. The growth plate of the tibial tuberosity has three distinct regions--(a) a zone of endochondral bone formation, (b) a zone of intramembranous bone formation through fibrocartilage, and (c) a zone of intramembranous bone formation through fibrous tissue.     

二齿钩钢板短期固定治疗骨骺未闭合青少年撕脱性骨折

目的　探讨二齿钩钢板短期固定治疗骨骺未闭合青少年撕脱性骨折效果。 方法　2012年1月~2016年11月,应用二齿钩钢板短期固定治疗骨骺未闭合青少年新鲜撕脱性骨折22例,其中男13例,女9例;年龄10~15岁,平均13.0岁;骨折类型（Salter-Harris分类）：I型8例,II型10例,III型3例,IV型1例;骨折部位：尺骨鹰嘴6例,肱骨内上髁4例,肱骨外上髁4例,肱骨大结节2例,外踝4例,内踝2例。术后均早期康复活动。骨愈合后及时取出内固定物。所有患者获12~28个月（平均18.2个月）随访。按DASH上肢功能调查表和Kaikkonen踝关节损伤功能评分,评价患肢功能恢复情况。 结果　切口均I期愈合,无血管神经损伤和感染。骨折均顺利愈合,未见移位和延迟愈合,无内固定松动或断裂。末次随访,患肢关节功能恢复优良率100%,无关节不稳,无明显骨骼发育畸形和创伤性关节炎。 结论　二齿钩钢板短期固定对骨骺或骺板无继发性、医源性损伤,是骨骺未闭合青少年撕脱性骨折较好的内固定方法,需注意勿过度加压和控制固定时间。     

Morphological alterations in the growth plate cartilage of ovariectomized mice

The effects of ovariectomy on growth and estrogen receptor (ER) expression level in the epiphyseal growth plate in mice have been estimated by histomorphometry and immunohistochemistry. Twelve female ddY mice, 8–9 weeks of age, were subjected to bilateral ovariectomy and 12 others were sham operated. They were then killed 8 weeks later. Ovariectomy significantly increased the total thickness of the distal femoral and proximal tibial growth plate cartilage. Ovariectomy caused a 1.4-fold increase in the thickness of the proliferative layer in the distal growth plate of the femur and a 1.3-fold increase in the thickness of the proliferative layer in the proximal growth plate of the tibia. ERα and ERβ immunoreactivity was detected in chondrocytes of the growth plate and the expression level of ERs in epiphyseal plates was increased in ovariectomized mice compared with controls. These data suggest that ERα and ERβ are coexpressed in the growth plates of the mice and that the cartilage growth and the level of expression of ERs in these tissues are hormonally regulated.     

跨骺钢板固定一定周期取出：继续观察一段时间后骺板的生长抑制情况

文题释义： 骨骺损伤：骺板软骨细胞共分为4层,骨骺损伤后骺软骨的结构发生了一系列修复重建性改变,其中骺板软骨增生层和肥大细胞层的细胞增生、分化、代谢活跃。由于肥大细胞层细胞增大,基质稀少,形成了骺板中最薄弱部位,故受到压力时变化最为显著。 骺板厚度变化率：为随着时间延长,骺板厚度逐渐增加,单位时间内骺板厚度增长的比率。主要是指不同时间节点,骺板厚度生长变化情况。用于观察跨骺板钢板内固定一段时间,取出内固定物后骺板厚度的生长变化情况。 背景：临床上儿童干骺端、骺板周围骨折比较常见,跨骺板钢板内固定对稳定骨折有较为重要的作用。但内固定一定周期后取出内固定物,继续观察一定时间骺板的发育恢复情况鲜有报道。 目的：设计骺板周围骨折动物模型,分析跨骺板置入锁定钢板一定周期取出钢板,继续观察一段时间后骺板的生长抑制情况。 方法：建立32只幼兔右股骨远端骺板上方5 mm骨折模型,随机分4组,每组8只。应用相同型号钢板和螺钉,跨骺板周围骨折线行钢板置入内固定。术后2,4,8,12周取出内固定物,继续观察2周处死幼兔。取出股骨标本,测量股骨长度;作病理切片,测量骺板厚度及肥大细胞计数;观察形态学中肥大细胞及骺板厚度变化情况。将骨折模型作为实验组,以左股骨远端骺板作为对照。 结果与结论：①实验组在内固定2周后,取出钢板继续观察2周,股骨长度、骺板厚度、肥大细胞计数等与对照组对比,差异无显著性意义;②实验组内固定4,8,12周,取出钢板继续观察2周,与对照组相比,实验组股骨长度、骺板厚度、肥大细胞计数等指标未能完全恢复至正常,差异有显著性意义(P < 0.05);③结果表明,在内固定物不伤及骺板的前提下,跨骺板钢板内固定初期(≤2周)取出钢板继续观察2周,适当压力作用对骺板生长发育未产生显著影响;④但持续过久压力限制时(≥4周),内固定对骺板压力限制时间过长,虽然也及时取出内固定,但肢体长度、骺板厚度、肥大细胞计数等指标均未能完全恢复正常,可导致骺板生长部分或者完全阻滞,引起肢体畸形及骺板发育停滞。 ORCID: 0000-0003-2448-9683(崔庆达) 中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程     

正常股骨头骨骺血供的多层螺旋CT灌注研究

目的：运用多层螺旋CT灌注技术,评价正常乳猪股骨头骨骺、骺板软骨、干骺端的血液供应特点。方法：对15只2周龄健康乳猪进行多层螺旋CT电影模式灌注扫描,共获得26个股骨头的完整图像资料;统计并比较骨骺、骺板软骨、干骺端三个解剖区域的血流量（BF）、血容量（BV）、平均通过时间（MTT）、对比剂峰值时间（TTP）,并与相应组织学观察结果相对照。结果：骺板软骨的BF高于骨骺（P〈0．05）。各解剖区域中,干骺端的BV最高（P〈0．05）、MTT最长（P〈0．05）,骺板软骨的1TrP最短（P〈0．05）。组织学检查发现,海绵状骨松质的血管密度最高（70～95支／mm^2）,其次为生长板软骨（60～80支／mm^2）,骨骺软骨的血管密度最小（15～25支／mm^2）。结论：多层螺旋CT灌注能够显示股骨头不同解剖区域的血液灌注特征。     

Effects of a sliding plate on morphology of the epiphyseal plate in goat distal femur

The aim of this study was to observe the effects of a sliding plate on the morphology of the epiphyseal plate in goat distal femur. Eighteen premature female goats were divided randomly into sliding plate, regular plate and control groups. Radiographic analysis and histological staining were performed to evaluate the development of epiphyseal plate at 4 and 8 weeks after surgery. In the sliding plate group, the plate extended accordingly as the epiphyseal plate grows, and the epiphyseal morphology was kept essential normal. However, the phenomenon of the epiphyseal growth retardation and premature closure were very common in the regular plate group. In addition, the sliding plate group exhibited more normal histologic features and Safranin O staining compared to the regular plate group. Our results suggest that the sliding plate can provide reliable internal fixation of epiphyseal fracture without inhibiting epiphyseal growth.     

带骨骺的儿童腓骨移植应用解剖学

解剖观察了70侧的儿童腓骨上骨骺的动脉来源、分布和吻合情况。其血供来源共见7种,胫前返动脉和腓浅动脉的腓骨头支是营养骨骺的重要血管。带骨骺儿童腓骨移植应以胫前动脉为血管蒂,腓骨体移植仍以腓血管为蒂。     

Oblique needle segmentation and tracking for 3D TRUS guided prostate brachytherapy

An algorithm was developed in order to segment and track brachytherapy needles inserted along oblique trajectories. Three-dimensional (3D) transrectal ultrasound (TRUS) images of the rigid rod simulating the needle inserted into the tissue-mimicking agar and chicken breast phantoms were obtained to test the accuracy of the algorithm under ideal conditions. Because the robot possesses high positioning and angulation accuracies, we used the robot as a "gold standard," and compared the results of algorithm segmentation to the values measured by the robot. Our testing results showed that the accuracy of the needle segmentation algorithm depends on the needle insertion distance into the 3D TRUS image and the angulations with respect to the TRUS transducer, e.g., at a 10 degrees insertion anglulation in agar phantoms, the error of the algorithm in determining the needle tip position was less than 1 mm when the insertion distance was greater than 15 mm. Near real-time needle tracking was achieved by scanning a small volume containing the needle. Our tests also showed that, the segmentation time was less than 60 ms, and the scanning time was less than 1.2 s, when the insertion distance into the 3D TRUS image was less than 55 mm. In our needle tracking tests in chicken breast phantoms, the errors in determining the needle orientation were less than 2 degrees in robot yaw and 0.7 degrees in robot pitch orientations, for up to 20 degrees needle insertion angles with the TRUS transducer in the horizontal plane when the needle insertion distance was greater than 15 mm.     

Glucosamine and chondroitin sulfate association increases tibial epiphyseal growth plate proliferation and bone formation in ovariectomized rats

OBJECTIVE:The growth plate consists of organized hyaline cartilage and serves as a scaffold for endochondral ossification, a process that mediates longitudinal bone growth. Based on evidence showing that the oral administration of glucosamine sulfate (GS) and/or chondroitin sulfate (CS) is clinically valuable for the treatment of compromised articular cartilage, the current study evaluated the effects of these molecules on the tibial epiphyseal growth plate in female rats.METHOD:The animals were divided into two control groups, including vehicle treatment for 45 days (GC45) and 60 days (GC60) and six ovariectomized (OVX) groups, including vehicle treatment for 45 days (GV45), GS for 45 days (GE45GS), GS+CS for 45 days (GE45GS+CS), vehicle for 60 days (GV60), GS for 60 days (GE60GS) and GS+CS for 60 days (GE60GS+CS). At the end of treatment, the tibias were dissected, decalcified and processed for paraffin embedding. Morphological and morphometric methods were employed for analyzing the distal tibial growth plates using picrosirius red staining and the samples were processed for histochemical hyaluronan detection. Morphometric analyses were performed using the 6.0ProPlus® Image system.RESULTS:Notably, after 60 days of treatment, the number of proliferative chondrocytes increased two-fold, the percentage of remaining cartilage increased four-fold and the percentage of trabecular bone increased three-fold in comparison to the control animals.CONCLUSION:GS and CS treatment drugs led to marked cellular proliferation of the growth plate and bone formation, showing that drug targeting of the tibial epiphyseal growth plate promoted longitudinal bone growth.     

膝关节动脉的血液供应

本文通过动脉灌注,对120侧不同年龄(新生儿至87岁)尸体的膝关节骨性部和软组织的血液供应分别进行了研究。新生儿的膝动脉在软骨内分布呈节段性,软骨骨化后,骨骺和髌骨的动脉间建立广泛的吻合。骺软骨板分隔膝关节的骨骺与干骺端。随骺板的闭合,两者间有血管互相交通。骺板的血液供应来自骺动脉、干骺动脉和滋养动脉终末的毛细血管袢以及骨膜动脉网的小支。髌骨的动脉分3组,发自髌前丛和髌周动脉环。滑膜和髌下脂垫的血管分布丰富。肌睫和韧带在骨的附着处缺乏血管。成人半月板外1/5有血管分布,内4/5无血管。本文对膝关节血管分布的临床意义作了简要讨论。     

Metaphyseal changes in Perthes' disease: an experimental study.

Glass microspheres were introduced into the hind-limb circulation of 6 immature Gottingen mini-pigs so as to result in ischaemia of the developing proximal femur. Radiological abnormalities similar to those seen in the metaphysis in Perthes'' disease were produced in 1 animal. Histological examination shows that these resulted from arrest of a portion of necrotic growth plate within the metaphysis with a corresponding defect within the growth plate. This was associated with ischaemia of the adjacent epiphysis. These changes support the suggestion that metaphyseal change in Perthes'' disease are secondary to epiphyseal ischaemia. It is possible that the growth-plate defect may be the precursor of intrinsic deformity of the femoral head.     

Animal model of experimentally induced ectopic enchondral ossification in nude mice with xenograft of porcine epiphyseal cartilage

In a specific animal model the induction of heterologous enchondral ossification was examined in long term follow-up. Physiologically normal and devitalized frozen porcine epiphyseal cartilage as a control group were transplanted as s.c. xenograft into athymic nude mice (nu/nu). 15 weeks after transplantation the porcine growth plate cartilage showed the development of viable cartilage tissue in the recipients, further differentiating to juvenile longe bone with epiphysis, diaphysis and growth plate. Porcine growth plate cartilage increased s.c. in the recipient nude mice, showing enchondral ossification without any physiological load, and finally an unexpected development towards complete juvenile long bone.     

显微内镜治疗神经根型颈椎病后侧入路的解剖学研究

目的　探讨后侧手术入路的显微内镜治疗神经根型颈椎病的可行性和安全性。方法　取 10具尸体的第 3～ 7颈椎。以其棘突中点连线为后正中线 ,上、下小关节突外缘为外边线 ,两侧上、下位椎板重叠内缘交点相连为横线 ,分别测量横线及外边线间距。距后正中线旁开 10mm处垂直插入定位针达相应间隙椎板后缘 ,测量进针深度 ,沿定位针逐层解剖 ,观测入路行径。结果　横线间距为 11 3 8～ 19 0 2mm ,平均每侧为后正中线旁开 5 69～ 9 5 1mm ,而边线间距为 4 6 3 2～ 5 7 2 8mm ,平均每侧为后正中线旁开 2 3 16～ 2 8 64mm。进针深度为 2 0 0 5～ 3 1 98mm。取距后正中线旁开 10mm处为进针点 ,进针角度以矢状面 0° ,横断面向下倾斜 0°～ 2 0°插入定位针 ,不会引起意外损伤。结论　后侧入路显微内镜治疗神经根型颈椎病是一种可行而安全的入路