经皮前路螺钉固定治疗枢椎齿状突骨折

 目的 回顾性分析经皮和开放前路螺钉固定治疗枢椎齿状突骨折, 比较两种方法的临床和影像学结果。方法 2003年 3月至 2010年 5月, 115例齿状突骨折患者接受前路螺钉固定治疗并获得随访。年龄 16~71岁, 平均 43.5岁。经皮固定组 47例: 域型骨折 42例, 浅芋型骨折 5例;采用经皮工作通道下前路螺钉固定。开放固定组 68例: 域型骨折 61例, 浅芋型 7例;采用传统开放手术方法治疗。分析两组手术时间、术中出血量、术者放射线暴露时间、骨折愈合和并发症等方面的差异。结果 115例患者均获得随访, 随访时间 12~70个月, 平均 37.6个月。术前两组性别、年龄、骨折类型、受伤至手术时间、伴发脊柱损伤情况差异无统计学意义。平均手术时间: 经皮固定组(40.3±9.5) min, 开放固定组(62.9±15.3) min, 经皮固定组显著短于开放组(P约 0.05)。术中平均出血量: 经皮固定组(5.6±4.1) ml, 开放固定组(47.1±28.6) ml, 经皮固定组显著少于开放组(P约 0.01)。两组在术者放射线暴露时间、骨折愈合情况和并发症发生率方面差异无统计学意义。结论经皮前路螺钉固定是一种安全有效的治疗域型或浅芋型齿状突骨折的方法, 与开放固定法比较创伤相对小。     

Management of odontoid fractures with percutaneous anterior odontoid screw fixation

Minimally invasive techniques have revolutionized the management of a variety of spinal disorders. The authors of this study describe a new instrument and a percutaneous technique for anterior odontoid screw fixation, and evaluate its safety and efficacy in the treatment of patients with odontoid fractures. Ten patients (6 males and 4 females) with odontoid fractures were treated by percutaneous anterior odontoid screw fixation under fluoroscopic guidance from March 2000 to May 2002. Their mean age at presentation was 37.2 years (with a range from 21 to 55 years). Six cases were Type II and four were Type III classified by the Anderson and D'Alonzo system. The operation was successfully completed without technical difficulties, and without any soft tissue complications such as esophageal injury. No neurological deterioration occurred. Satisfactory results were achieved in all patients and all of the screws were in good placement. After a mean follow-up of 15.7 months (range 10-25 months), radiographic fusion was documented for 9 of 10 patients (90%). Neither clinical symptoms nor screw loosening or breakage occurred. Our preliminary clinical results suggest that the percutaneous anterior odontoid screw fixation procedure using a new instrument and fluoroscopy is technically feasible, safe, useful, and minimally invasive.     

Management of odontoid fractures with anterior screw fixation

Type II odontoid fractures are prone to undergo nonunion. Stabilization of such fractures with anterior screw fixation provides rigid internal fixation and preserves C1-C2 motion. During a 5-year period, 17 patients with displaced type II fractures of the odontoid were treated Thirteen were male and four were female with a mean age of 38.2 years. All patients were operated on for anterior screw fixation within a mean of 10.1 days from injury. Postoperatively, the patients were evaluated clinically and radiologically at regular intervals. With a mean follow-up of 3.2 years, union was observed in 16 of 17 patients (94%). One patient developed nonunion for which he required C1-C2 fusion subsequently. Screw back-out by a few millimeters was seen in another patient resulting in mild restriction of neck movements. No approach-related complications were noted. Anterior odontoid screw fixation has relatively low complication and high fusion rates. It not only restores normal anatomy but also gives better functional results by preserving intrinsic C1-C2 motion. Thus it should be considered the treatment of choice in acute displaced type II odontoid fractures.     

经皮前路枢椎齿状突螺钉内固定术的并发症分析

目的 :分析经皮前路齿状突螺钉内固定术治疗枢椎齿状突骨折的并发症及相关防治措施。方法 :2006年6月~2013年12月共收治新鲜枢椎齿状突骨折患者122例,其中男79例,女43例,年龄28~73岁(45.6±14.8岁)。根据Anderson-D′Alonzo分型,Ⅱ型88例,浅Ⅲ型34例。均采用经皮颈椎前路枢椎齿状突螺钉内固定术。记录手术时间,术中出血量,螺钉松动及断裂,医源性血管、神经及食管损伤和切口感染等情况。术后及随访时行颈椎正侧位、开口位X线片及CT检查评估螺钉位置和骨折愈合情况,并记录并发症处理措施。结果:皮肤切口长约0.8~1cm,手术时间40.7±12.2min,术中出血量20ml。术中未发生咽后壁、食管、血管和重要神经等邻近组织损伤。共21例患者出现相关并发症,其中3例在置入螺钉过程中产生枢椎前方骨折,1例术中再置入1枚螺钉行双螺钉固定,另2例术后予Halo-Vest架固定治疗后齿状突骨折骨性愈合;1例术后骨折端分离过大,再次行内窥镜下骨折端植骨术而愈合;1例骨折端轻度移位,术后予以支具固定后骨性愈合;9例螺钉钉尾留置过长,但未出现临床症状;1例术后2d出现喉上神经麻痹,经营养神经治疗后恢复正常;1例切口感染,经抗感染治疗后痊愈;2例分别在术后2个月、3个月出现螺钉脱出,均予翻修,1例行前路寰枢关节融合内固定术,另1例行后路寰枢关节融合内固定术;3例纤维连接,齿状突骨折处无移位,内固定无松动,无需佩戴颈围和二次手术。结论:经皮前路齿状突螺钉内固定术是一种方便、安全、微创的手术方式,术后并发症多数经处理后预后良好,整体翻修率低。     

Fractures of the odontoid process. Treatment with anterior screw fixation

Seventeen cases of Anderson and D'Alonzo Type II and "shallow" Type III fractures of the odontoid, treated by anterior screw fixation, were reviewed and compared with previously published series of fractures treated nonoperatively, treated with posterior C1-C2 arthrodeses, and with anterior screw fixation series. Although the nonunion rate (12%) and major complication rate (24%) in the present series were higher than those previously reported, the combined rates of all anterior screw fixation series were comparable to those of posterior C1-C2 arthrodesis studies. Three of the complications presented occurred in cases that in retrospect were inappropriate for the use of this technique. These included a verified nonunion and 2 individuals with markedly osteoporotic bone and unfavorable fracture type. Because of the difficulty involved in mastering anterior screw fixation of the dens, its use should be limited to experienced spine surgeons with the appropriate surgical facilities.     

经皮颈前路螺钉内固定治疗齿突骨折

目的采用自行设计的器械行经皮颈前路螺钉内固定治疗齿突骨折。方法对40名20～45岁正常人行齿突CT扫描,测量齿突基底冠状径与矢状径、齿突长度、枢椎总高度、齿突轴心线与C3椎体前上缘重力线的夹角。10例齿突骨折患者,其中AndersonⅡ型骨折4例,Ⅲ型骨折6例。骨折端无移位4例,移位小于5mm3例,移位大于5mm3例。新鲜骨折8例,陈旧骨折2例。牵引复位后,在C4,5水平右胸锁乳突肌内侧做5mm切口,于“C”型臂X线机监视下将定位克氏针打入齿突,用单枚3.5mm中空螺钉固定。陈旧性骨折者同期行前路植骨。结果齿突基底冠状径为(8.8±1.2)mm,矢状径为(10.9±1.0)mm,齿突长度为(14.2±1.2)mm,枢椎总高度为(38.2±1.8)mm,齿突轴心线与C3椎体前上缘重力线的夹角为23.1°±1.4°。10例患者内固定均较满意,螺钉位于齿突中央,无偏斜。全部病例随访10～25个月,平均19个月。8例骨性愈合,2例不愈合,但无临床症状。本组无一例发生螺钉松动及断裂。结论经皮颈前路螺钉内固定治疗齿突骨折可保留寰枢椎间的运动功能,手术操作简单,创伤小,恢复快,但应严格掌握手术适应证。经皮固定以一枚螺钉为宜。     

Metastatic odontoid fracture management by anterior screw fixation and kyphoplasty

We report the case of a patient diagnosed with a pathological fracture of the odontoid dens related to a renal carcinoma metastasis and treated by an original technique. In order to achieve correct stabilization of the fracture and to preserve rotational neck mobility, an anterior approach combining an odontoid screw fixation and a balloon kyphoplasty was performed. This minimal invasive strategy provided satisfactory clinical and radiological results for this unstable lesion. To our knowledge, this technique has not been previously reported and could be a valuable alternative approach in the management of craniocervical metastatic lesions for these fragile patients.     

A novel endoscopic approach to anterior odontoid screw fixation: technical note.

Techniques for operative management for type II odontoid fractures have continuously been refined with anterior odontoid screw arthrodesis having a clear advantage in maintaining normal motion. We have refined the technique of odontoid screw fixation further with the introduction of an endoscopic approach developed by the senior author. The necks of two partially embalmed cadavers were slightly extended under fluoroscopic guidance to simulate a reduced, anteriorly displaced type II fracture. Using a guide wire, graduated plastic sheath and endoscopic guidance, a solid 45 mm bone screw was passed through the odontoid with the aid of biplanar fluoroscopy. There were no apparent complications and no damage to surrounding vital structures. Anterior screw fixation of the odontoid is an established technique that provides adequate fixation, but the procedure can be technically demanding secondary to awkward tissue retraction. We present a percutaneous technique that obviates the need for tissue retraction while achieving an excellent result with only a modicum of effort.     

颈前路单枚中空加压螺钉内固定治疗齿突骨折

目的初步比较经颈前路单枚单头螺纹中空加压螺钉与双头螺纹中空加压螺钉内固定治疗齿突骨折的效果。方法1997年4月～2003年4月,对20例齿突骨折行经颈前路单枚中空加压螺钉内固定术,其中单头螺纹中空加压螺钉12例,双头螺纹中空加压螺钉8例。Anderson分型:Ⅱ型16例,浅Ⅲ型4例。其中3例伴有单侧椎间关节内撕脱性骨折。观察手术时间、术中出血量、术后骨折愈合以及颈部活动情况。结果手术时间110～150min,平均125min。术中出血20～100ml,平均42ml。术中无一例发生副损伤。术后随访2～72个月,平均14.7个月;19例骨折正常愈合,1例延迟愈合;17例骨折愈合后颈椎活动恢复正常,3例伴单侧椎间关节内骨折者颈部旋转功能较正常减少20%。两种螺钉固定的手术时间、术中出血量、骨折愈合时间和颈椎活动功能无明显差别,差异无显著性(P >0.05)。结论单枚单头螺纹中空加压螺钉与单枚双头螺纹中空加压螺钉固定齿突骨折均可获得良好效果。     

Direct anterior fixation of odontoid fractures with a hollow spreading screw system

Summary Direct fixation of odontoid fractures has the advantage of preserving rotation in the atlanto-axial motion segment. Early mobilisation of patients and minor intra-operative trauma increase the value of this technique. The original screw method of Nakanishi, Magerl, and Böhler, was improved by Knöringer who designed a doublethreaded screw for direct fixation of dens axis fractures. He stated that double screwing is absolutely necessary in order to prevent rotation of fragments against each other.The purpose of the present study was to describe a new single screw for direct fixation of odontoid fractures, which is easy to place into the limited space of the dens axis and which offers enough rotational stability and sufficient compression of fracture fragments. The so-called hollow spreading screw system (HSS) consists of an outer hollow screw, a spreading insert, a toothed washer, an hexagonal nut, and a protective nut.Thirty-five patients with traumatic and arthritic odontoid fractures were treated using direct internal fixation with the HSS system. In 30 cases, there was a type-II-fracture, in 3 a shallow type-III-fracture, and in 2 a type-II-fracture with pseudarthrosis formation. Pre-operative neurological deficits were seen in 16 cases.No additional neurological deficits were caused by the surgical procedure. The bony fusion rate of fresh fractures in the presented series was 100%. With the HSS system, ca. 12% postoperative complications, such as slight reduction of head rotation or neck pain, were found. These results are virtually equal to the results of the double-screw technique. Since a relatively simple technical procedure is required for placement of the screw, the HSS system can be recommended in all cases of odontoid fractures suitable for direct anterior fixation.     

经颈前路单枚双头螺纹中空加压螺钉内固定治疗齿突骨折

目的 评价经颈前路单枚双头螺纹中空加压螺钉内固定治疗齿突骨折的疗效。方法 回顾分析1999年10月至2003年10月间，应用颈前路单枚双头螺纹中空加压螺钉内固定治疗11例齿突骨折的效果。其中Anderson分类Ⅱ型10例．浅Ⅲ型1例，1例伴有单侧椎间关节内撕脱性骨折。术后临床和X线随访3～57月．平均15．3月。术前日本矫形外科协会(Japanese Orthopaedic Association，JOA)颈髓症评分：16～17分．平均16．5分。结果 手术时间100～150min．平均110min。术中出血量20～60ml，平均35ml。无一例发生副损伤。10例正常愈合，1例延迟愈合；伴单侧椎间关节内骨折的1例颈部旋转活动部分受限，术后JOA评分均达17分。结论 单枚双头螺纹中空加压螺钉固定齿突骨折术后可获得即刻稳定性、骨折融合率高，有利于患者早期活动。     

Anterior screw fixation of odontoid fractures

BACKGROUND: Anterior screw fixation is the best treatment for odontoid fractures when the fracture line is horizontal or oblique downward and backward, as it preserves atlantoaxial mobility, especially axial rotation. Some details regarding patient positioning and operative technique need to be stressed to obtain the best results and avoid complications. METHODS: Between 1989 and 1997, we treated 17 cases of odontoid fracture by anterior screw fixation. Only two patients presented with motor neurologic deficit. Fracture line was horizontal in 3 cases and oblique downward and backward in 14 cases. RESULTS: Adequate reduction and fixation was obtained in all cases except one, where posterior displacement of the screw occurred without neurologic complications. Functional result was satisfactory in all cases except two, where we noted significant limitation of cervical rotation. CONCLUSION: Successful anterior screw fixation gives the best anatomical and functional results for odontoid fractures. Correct installation is very important for operative success.     

齿状突骨折经皮螺钉内固定手术前后CT重建的意义

目的:探讨齿状突骨折经皮螺钉内固定手术前后应用CT重建的意义。方法:16例齿状突骨折患者,术前进行上颈椎CT扫描及图像后处理,观察齿状突骨折的部位、骨折线走向及移位情况,并测量齿状突解剖学数据。均行经皮前路齿状突螺钉内固定术,术后不同时期同样进行CT重建,以观察齿状突骨折复位、螺钉内固定及骨折愈合等。结果:16例齿状突骨折患者中,AndersonⅡ型10例,其中EyselA型3例,B型2例,C型5例;AndersonⅢ型6例。齿状突基底冠状径8.7±1.1mm,矢状径10.9±1.1mm,齿状突骨折远段长度12.3±1.1mm,齿状突后倾角23.3°±1.2°;术后CT重建证实16例患者中,11例复位及螺钉位置良好,2例螺钉位置有偏斜,2例螺纹未完全通过骨折线,1例螺钉穿破齿状突尖部皮质。随访发现15例达到骨性愈合,1例EyselC型骨折经10个月随访仍未见到骨性愈合,继续随访观察中。结论:经皮前路螺钉内固定治疗齿状突骨折术前、术后行CT重建有利于准确评估骨折状况、制定周密手术方案及评价手术效果。     

双孔导管在经皮颈椎前路枢椎齿状突螺钉内固定术中的应用

目的 :探讨双孔导管在经皮颈椎前路枢椎齿状突螺钉内固定术中的应用价值。方法 :22例新鲜齿状突骨折患者,男性18例,女性4例,平均年龄40.5±14.7岁,按照Anderson-D′Alonzo分型,17例为Ⅱ型,5例为浅Ⅲ型。骨折端无移位6例,移位小于5mm 10例,移位大于5mm 6例。所有患者均采用经皮颈椎前路枢椎齿状突螺钉内固定,且因术中初始置入的导针位置不满意而采用双孔导管调整。分析该技术的手术时间、出血量、骨折复位、骨折愈合和并发症情况。结果:所有患者的枢椎齿状突导针经过采用双孔导管后均调整成功并置入螺钉,手术时间35±12min,出血20ml。20例骨折获得基本解剖复位,2例仍有小于3mm移位。术中和术后无明显技术有关的并发症发生,螺钉位置正确。平均随访16.7个月,无寰枢关节不稳或脱位,21例获得骨融合,1例纤维连接,无需佩戴颈围和二次手术,随访中无螺钉松动、脱出或断裂发生。结论:采用双孔导管调整并置入导针,具有操作容易、快速和准确的优点,减少了术者和患者的放射线暴露,保证了齿状突螺钉处于正确位置。     

Efficacy of anterior odontoid screw fixation in the elderly patient: a CT-based biometrical analysis of odontoid fractures

In the elderly population, reported union rates with anterior odontoid screw fixation (AOSF) for odontoid fracture (OF) treatment vary between 23 and 93% when using plain radiographs. However, recent research revealed poor interobserver reliability for fusion assessment using plain radiographs compared to CT scans. Therefore, union rates in patients aged ≥60 years treated with AOSF have to be revisited using CT scans and factors for non-union to be analysed. Prospectively gathered consecutively treated patients using AOSF for odontoid fracture with age ≥60 years were reviewed. Medical charts were assessed for demographics, clinical outcomes and complications. Patients’ preoperative radiographs and CT scans were analysed to characterize fracture morphology and type, fracture displacement, presence of atlanto-dental osteoarthritis as well as a detailed morphometric assessment of fracture surfaces (in mm²). CT scans performed after a minimum of 3 months postoperatively were analysed for fracture union. Those patients not showing CT-based evidence of completely fused odontoid fracture were invited for radiographic follow-up at a minimum of 6 months follow-up. Follow-up CT-scan were studied for odontoid union as well as the number of screws used and the square surface of screws used for AOSF and the related corticocancellous osseous healing surface of the odontoid fragment (in %) were calculated. Patients were stratified whether they achieved osseous union or fibrous non-union. Patients with a non-union were subjected to flexion–extension lateral radiographs and the non-union defined as stable if no motion was detected. The sample included 13 male (72%) and 5 female (18%) patients. The interval from injury to AOSF was 4.1 ± 5.3 days (0–16 days). Age at injury was 78.1 ± 7.6 years (60–87 years) and follow-up was 75.7 ± 50.8 months (4.2–150.2 months). 10 patients had dislocated fractures, 14 had Type II and 4 “shallow” Type III fractures according to the Anderson classification, 2 had stable C1-ring fractures, 8 had displayed atlanto-dental osteoarthritis. Fracture square surface was 127.1 ± 50.9 mm² (56.3–215.9 mm²) and osseous healing surface was 84.0 ± 6.8% (67.6–91.1%). CT-based analysis revealed osseous union in 9 (50%) and non-union in 9 patients (50%). Union rates correlated with increased fracture surface (P = 0.02). Statistical analysis revealed a trend that the usage of two screws with AOSF correlates with increased fusion rates (P = 0.06). Stability at C1–2 was achieved in 89% of patients. CT scans are accepted as the standard of reference to assess osseous union. The current study offers an objective insight into the union rates of odontoid fractures treated with AOSF using CT scans in consecutive series of 18 patients ≥60 years. Literature serves evidence that elderly patients with unstable OF benefit from early surgical stabilization. However, although using AOSF for unstable OF yields segmental stability at C1–2 in a high number of patients as echoed in the current study, our analysis stressed that using follow-up CT scans in comparison to biplanar radiographs dramatically reduces osseous union rates compared to those previously reported for AOSF.     

Cement-augmented anterior screw fixation of Type II odontoid fractures in elderly patients with osteoporosis

Background contextClosed reduction and internal fixation by an anterior approach is an established option for operative treatment of displaced Type II odontoid fractures. In elderly patients, however, inadequate screw purchase in osteoporotic bone can result in severe procedure-related complications.PurposeTo improve the stability of odontoid fracture screw fixation in the elderly using a new technique that includes injection of polymethylmethacrylat (PMMA) cement into the C2 body.Study designRetrospective review of hospital and outpatient records as well as radiographs of elderly patients treated in a university hospital department of orthopedic surgery.Patient sampleTwenty-four elderly patients (8 males and 16 females; mean age, 81 years; range, 62–98 years) with Type II fractures of the dens.Outcome measuresComplications, cement leakage (symptomatic/asymptomatic), operation time, loss of reduction, pseudarthrosis and revision surgery, patient complaints, return to normal activities, and signs of neurologic complications were all documented.MethodsAfter closed reduction and anterior approach to the inferior border of C2, a guide wire is advanced to the tip of the odontoid under biplanar fluoroscopic control. Before the insertion of one cannulated, self-drilling, short thread screws, a 12 gauge Yamshidi cannula is inserted from anterior and 1 to 3 mL of high-viscosity PMMA cement is injected into the anteroinferior portion of the C2 body. During polymerization of the cement, the screws are further inserted using a lag-screw compression technique. The cervical spine then is immobilized with a soft collar for 8 weeks postoperatively.ResultsAnatomical reduction of the dens was achieved in all 24 patients. Mean operative time was 64 minutes (40–90 minutes). Early loss of reduction occurred in three patients, but revision surgery was indicated in only one patient 2 days after primary surgery. One patient died within the first eight postoperative weeks, one within 3 months after surgery. In five patients, asymptomatic cement leakage was observed (into the C1–C2 joint in three patients, into the fracture in two). Conventional radiologic follow-up at 2 and 6 months confirmed anatomical healing in 16 of the19 patients with complete follow-up. In two patients, the fractures healed in slight dorsal angulation; one patient developed a asymptomatic pseudarthrosis. All patients were able to resume their pretrauma level of activity.ConclusionsCement augmentation of the screw in Type II odontoid fractures in elderly patients is technically feasible in a clinical setting with a low complication rate. This technique may improve screw purchase, especially in the osteoporotic C2 body.