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.     

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。     

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。     

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.     

Anterior screw fixation of posteriorly displaced type II odontoid fractures

Posteriorly displaced Type II odontoid fractures (Type II-P) are difficult to stabilize in an anatomic position with accepted methods of posterior atlantoaxial arthrodesis. Nine patients with Type II-P odontoid fractures with 4 to 15 mm displacement were treated with anterior odontoid screw stabilization. Seven of these patients had associated fractures or defects of the posterior arch of the first cervical vertebra (C1). Atlantoaxial posterior arthrodesis in these patients would not have been possible initially because of the lack of structural integrity of the posterior arch of C1. Two patients, later in the study, had no injury to the ring of C1. The odontoid fractures were stabilized with two 4.0-mm cancellous screws inserted through an anterior approach to the neck under fluoroscopic control with the skin incision at the C5 level. Preoperative reduction of the displaced odontoid process and immediate operative stability of the atlantoaxial complex were obtained in each case. No neurological complications related to the procedure occurred. Two patients died of causes unrelated to their cervical fracture surgery. The 7 patients who survived were followed for a minimum of 6 months. Fracture union and cervical stability were demonstrated in each of the surviving patients, without evidence of screw loosening or loss of fixation. Normal range of motion of the neck was documented at follow-up in all surviving patients. Although this series represents a limited experience with this treatment technique, anterior odontoid screw fixation has significant advantages over accepted methods of cervical stabilization for Type II-P odontoid fractures.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anterior single-screw fixation in 24 patients with Type II odontoid fractures

BackgroundFractures of the odontoid process make up 9–15% of adult cervical fractures; Type II odontoid fractures are the most common type. Most patients with these fractures recover after early treatment utilizing the proper surgical approach.Purpose/AimsA retrospective study was performed to evaluate the bone union rate and to identify factors that might contribute to non-union in patients undergoing anterior single-screw fixation for Type II odontoid cervical fractures.MethodsFrom November 2000 to December 2008, 24 patients (16 males, 8 females) underwent anterior single-screw fixation for Type II odontoid cervical fractures. Prior to surgery, all patients had cervical spine radiographs and computed tomographic (CT) scans. Surgery to correct the fractures used the technique of Abfelbaum et al, and fluoroscopy was used to confirm spinal stability. At follow-up, bone fusion was considered successful if trabeculation across the fracture site was seen on lateral radiographic studies. Non-union was confirmed when the fracture line was visible on follow-up lateral radiographic studies. After surgery, all patients were followed at approximately 2 weeks, 4 weeks, 6 weeks, 3 months, 6 months, 9 months, and annually thereafter.ResultsAll 24 patients had odontoid fractures confirmed by radiographic films and CT scans. Twenty-three patients had Type II odontoid fractures that were posterior-oblique or horizontal, and one had an anterior oblique fracture. Twenty patients achieved successful fusion. The presence of a lag effect was significantly different between patients who had successful fusion and the four patients with fusion failure. All patients achieved immediate spinal stabilization after surgery and none experienced major neurologic sequelae.ConclusionsAnterior single-screw fixation is an effective and safe surgical approach for patients with Type II odontoid fractures. A satisfactory long-term outcome depends upon careful selection of patients for fracture orientation and attention to the technical aspects of surgery.     

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.     

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.     

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。     

Fixation of odontoid fractures by an anterior screw

We have reviewed 81 patients with fractures of the odontoid process treated between May 1983 and July 1997, by anterior screw fixation. There were 29 patients with Anderson and D'Alonzo type-II fractures and 52 with type III. Roy-Camille's classification identified the direction and instability of the fracture. Operative fixation was carried out on 48 men and 33 women with a mean age of 57 years. Associated injuries of the cervical spine were present in 15 patients, neurological signs in 13, and 18 had an Injury Severity Score of more than 15. Nine patients died and 11 were lost to follow-up. Of 61 patients, 56 (92%) achieved bony union at an average of 14.1 weeks. Two patients required a secondary posterior fusion after failure of the index operation. A full range of movement was restored in 43 patients; only six had a limitation of movement greater than 25%. We conclude that anterior screw fixation is effective and practicable in the treatment of fractures of the dens.     

经皮前路螺钉内固定术在老年齿状突骨折中的应用

目的:探讨经皮前路螺钉内固定术治疗老年齿状突骨折的疗效。方法:自2001年2月至2009年4月对15例老年齿状突骨折采用经皮前路螺钉内固定术,男13例,女2例;年龄60～86岁,平均69.3岁。根据Anderson分类:Ⅱ型10例,浅Ⅲ型4例,深Ⅲ型1例;10例Ⅱ型骨折按Eysel和Roosen分类,ⅡA型7例,ⅡB型3例。新鲜骨折13例,陈旧性骨折2例。所有患者有不同程度颈肩部疼痛及颈部活动受限症状,其中4例伴神经损伤症状,根据Frankel分级:D级2例,C级2例。对患者进行术后随访及影像学评估,临床检查包括术后颈部活动、神经功能及疼痛改善情况;影像学检查包括颈椎正侧位、张口位及过屈、过伸位X线片。结果:所有患者获随访,时间6～60个月,平均31.3个月,2例随访期间死于其他疾病(分别为术后18、22个月)。末次随访时内固定满意,螺钉位置良好,无偏斜,1例螺钉尾部过长,并向前方轻度压迫食管,1例纤维愈合,12例骨性愈合,2例不愈合,但无临床症状。除3例颈部旋转轻度受限外,其余患者颈部活动无明显障碍。4例伴神经损伤症状患者术后神经功能均有改善,至末次随访为止,根据Frankel分级:E级3例,D级1例。颈部疼痛较术前明显改善(P<0.001),VAS评分由术前平均(6.07±1.44)分(4～8分)降至术后的平均(1.13±0.92)分(0～3分)。无严重术后并发症,无血管、神经损伤。结论:经皮前路螺钉内固定术治疗老年齿状突骨折具有操作易、创伤小、恢复快等优点。只要全面评估患者一般情况,可达到满意的临床效果,对于齿状突粉碎性骨折、严重骨质疏松患者则不宜采用此手术。     

颈前路单枚空心钉固定治疗齿状突Ⅱ型骨折

目的应用颈前路单枚空心钉固定治疗齿状突Ⅱ型骨折的临床观察。方法对21例齿状突ⅡA型5例、ⅡB型16例骨折行颈前路单枚空心钉固定治疗。结果 21例全部获得随访12-36个月,平均21个月。术后无感染,枕颈部疼痛消失,无吞咽不适感,6例术前ASIA分级为D级的患者在术后3个月恢复为E级。骨折平均愈合时间5.5个月,骨折愈合率为100%。随访X线片显示颈椎序列及生理曲度恢复满意,患者颈部屈伸及旋转活动恢复正常,未发生螺钉松动、移位及断裂等。结论采用颈前路单枚空心钉固定治疗齿状突Ⅱ型骨折是一种有效的手术方法。