椎弓根螺钉+髂骨螺钉系统固定治疗骨盆后环不稳

目的探讨椎弓根螺钉结合髂骨螺钉复位固定治疗骨盆后环不稳定的临床疗效。方法对12例骶髂关节骨折(脱位)患者采用后路椎弓根螺钉结合髂骨螺钉复位固定。结果患者骶髂关节均达到解剖复位,未发生血管、神经损伤等并发症。12例均获随访,时间6～16个月。骶髂关节均获融合。结论椎弓根螺钉结合髂骨螺钉固定对于骨盆后环不稳定骨折脱位有良好的复位固定作用,临床疗效良好。     

椎弓根螺钉结合髂骨板间螺钉固定技术治疗骶髂关节骨折脱位的临床初步观察

目的 探讨椎弓根螺钉结合髂骨板间螺钉固定技术治疗骶髂关节骨折脱位的临床应用效果.方法 骶髂关节骨折脱位6例,均采用ISOLA脊柱后路骨固定系统进行复位固定.结果 本组6例均获得随访,所有患者无一例发生感染、神经损伤及螺钉松支架、断裂等现象,腰骶及下肢活动接近正常.结论 椎弓螺钉结合髂骨板间螺钉固定技术治疗骶髂关节骨折脱位可获得良好疗效,为治疗骶髂关节骨折脱位一种行之有效的方法.     

微创后路髂骨内固定系统治疗骶髂关节复合体损伤

目的探讨椎弓根螺钉髂骨内固定技术治疗骶髂关节复合体的临床应用效果。方法骶髂关节骨折脱位13例,采用微创后路内固定系统进行复位固定。结果本组患者均获得随访,所有患者无1例发生感染、神经损伤及螺钉松动、断裂等现象,腰骶及下肢活动接近正常。结论椎弓根螺钉固定技术治疗骶髂关节骨折脱位可获得良好疗效,为治疗骶髂关节骨折脱位一种行之有效的微创治疗方法。     

以S_1椎弓根为轴固定术治疗骨盆后环损伤

目的探讨以S1椎弓根为轴固定术治疗骨盆后环损伤的疗效。方法将2004年1月～2007年6月治疗资料完整54例骨盆后环损伤进行分析,侧方途径采用俯卧位、仰卧位及仰卧位CT引导下经皮置入1枚骶髂空心螺钉固定治疗骨盆后环损伤。后路途径在髂骨后部、一侧S1椎弓根及另一侧S1椎弓根或L5椎弓根各置入1枚多轴椎弓根螺钉,形成骶-髂或腰-骶-髂固定术,配合骨盆前方固定重建骨盆环稳定性。结果平均随访18个月,骨折均愈合。无明显盆部畸形、双下肢不等长和骶髂部疼痛。按Majeed功能评定标准,优良率92.6%(50/54)。结论根据患者病情和骨折类型,选择以S1椎弓根为轴固定术治疗骨盆后环损伤,可取得满意疗效。     

经前路内固定植骨融合治疗骶髂关节骨折脱位

目的探讨经前路手术复位内固定植骨融合治疗骶髂关节骨折脱位的安全性和疗效。方法采用骶髂关节前部切口或髂腹股沟切口,显露骶髂关节前面,对12例骶髂关节骨折脱位复位后,应用骨盆重建钢板内固定并植骨融合。结果3例单纯施行切开复位内固定融合术,9例同时行骨盆前环骨折复位内固定术;2例同时行髋臼骨折手术。随访6~18个月,6例垂直移位复位,9例旋转移位纠正,骶髂关节完全融合。结论骶髂关节骨折脱位造成整个骨盆环的严重失稳,经前路重建钢板内固定植骨融合治疗骶髂关节骨折脱位,能有效避免神经损伤,疗效肯定。     

脊柱骨盆内固定系统治疗骶髂关节骨折脱位

[目的]探讨脊柱骨盆内固定系统治疗骶髂关节骨折脱位的疗效。[方法]2007年8月²011年11月共收治骶髂关节骨折脱位患者14例,其中男12例,女2例;年龄222011年11月共收治骶髂关节骨折脱位患者14例,其中男12例,女2例;年龄22⁵7岁,平均42.3岁;交通事故伤11例,高处坠落伤3例。合并骨盆前环骨折9例,骶丛神经损伤4例,四肢骨折6例,尿道断裂1例。根据骨盆环损伤的Tile分型法,该组病例均为骶髂关节复合体旋转垂直不稳定,C1型5例,C2型9例。14例患者均行脊柱骨盆内固定系统治疗。受伤至手术时间757岁,平均42.3岁;交通事故伤11例,高处坠落伤3例。合并骨盆前环骨折9例,骶丛神经损伤4例,四肢骨折6例,尿道断裂1例。根据骨盆环损伤的Tile分型法,该组病例均为骶髂关节复合体旋转垂直不稳定,C1型5例,C2型9例。14例患者均行脊柱骨盆内固定系统治疗。受伤至手术时间7¹4 d。术前经骨牵引,使骶髂关节骨折脱位基本复位后,采用Colorado2TM脊柱内固定系统和髂骨螺钉固定骶髂关节。应用Majeed评分标准评价患者功能恢复情况。应用PACS软件系统测量患者术后即刻及术后1年骶髂关节中部间隙变化,评价内固定的有效性。[结果]14例患者均获随访,随访时间1614 d。术前经骨牵引,使骶髂关节骨折脱位基本复位后,采用Colorado2TM脊柱内固定系统和髂骨螺钉固定骶髂关节。应用Majeed评分标准评价患者功能恢复情况。应用PACS软件系统测量患者术后即刻及术后1年骶髂关节中部间隙变化,评价内固定的有效性。[结果]14例患者均获随访,随访时间16²4个月,平均21.3个月。术后X线片复查示骶髂关节垂直和旋转移位均获满意复位,骶髂关节得到有效固定,未发生严重的血管、神经损伤等并发症。未发现内固定松动、断裂,骶髂关节无再移位情况发生。Majeed评分获优6例,良4例,一般3例,差1例。[结论]脊柱骨盆内固定系统可使骨折脱位的骶髂关节获得有效的即刻稳定性并维持至骨折愈合,是治疗骶髂关节骨折脱位的有效方法之一。     

联合Galveston技术和TSRH系统治疗严重骶髂关节骨折脱位的初步报告

骶髂关节骨折脱位是最不稳定的骨盆环损伤,它通常合并耻骨联合分离及耻骨支骨折,造成前后环均损伤。传统的非手术疗法常遗留疼痛和骨盆垂直及旋转不稳。研究证实,如果复位不满意,可导致功能障碍[1～4 ] ,而骶髂关节的垂直移位靠传统的外固定架及拉力螺钉、钢板和棒等复位是困难的。作者采用Galveston技术结合TSRH系统治疗骶髂关节骨折脱位3例取得较好效果。1　材料和方法1.2　病例资料　本组3例,男2例,女1例。年龄分别为36、4 2、2 2岁。损伤原因:交通事故伤2例,压伤1例。其中1例伴有股骨干骨折。所有患者均为TileC型骨折,C1型1例,C2 型…     

骨盆后环损伤的内固定治疗

目的 探讨手术内固定治疗骨盆后环损伤的临床疗效.方法 对22例骨盆后环损伤患者分别采用微创技术椎弓根螺钉固定、骶髂关节空心螺钉固定及骨盆重建带后方髂髂固定3种方式治疗.结果 22例均随访,时间4~22个月.无切口感染、血管神经损伤及内固定松动或断裂,无骨折不愈合.结论 微创椎弓根螺钉固定、骶髂关节空心螺钉固定及骨盆重建带后方髂髂固定3种方式均为治疗骨盆后环损伤的有效方法,根据骨折类型及患者的情况选择不同的内固定方式,可获满意疗效.     

骶髂关节螺钉固定应用及CT与解剖学研究

目的 :采用CT扫描测量髂骨翼后外侧面至第 1骶椎 (S1)的距离和S1椎弓根宽 ,为临床上经骶髂关节螺钉固定治疗后骨盆环不稳定提供参考。方法 :对 2 2例中国成人的骨盆标本共 4 4侧骶髂关节进行CT和解剖学研究 ,测量S1椎弓根宽 ,髂骨翼后外侧面的进针点至S1椎弓根中心距离 ,进针点至S1椎体对侧前皮质距离 ,并对解剖测量值和CT测量值进行比较。在实验研究的基础上 ,对 11例垂直不稳定后骨盆环骨折进行骶髂螺钉固定。结果 :髂骨翼后外侧面的进针点至椎弓根中心距离解剖和CT测量值分别为 4 9 5± 4 0mm和 4 9 2± 3 9mm ,两者差异无显著性 (P >0 0 5 ) ;进针点至S1椎体对侧前皮质距离解剖和CT测量值分别为 86 9± 4 6mm和 86 4± 4 4mm ,两者差异无显著性 (P >0 0 5 ) ;S1椎弓根宽解剖和CT测量值分别为 2 7 7± 2 0mm和 2 0 7± 2 5mm ,两者差异有显著性 (P <0 0 1)。临床 11例共 13枚骶髂螺钉均准确置入 ,无骨皮质穿破或神经血管损伤等并发症。结论 :术前CT扫描可准确地推算骶髂螺钉长度 ,具有临床实用意义。     

旋转和垂直不稳定型骨盆骨折的手术治疗

目的：探讨旋转和垂直不稳定型骨盆骨折的临床特点及其治疗方法选择。方法：17例存在旋转和垂直不稳定的骨盆骨折患者，全部行手术治疗：骨盆前环均行切开复位内固定，骨盆后环11例采用行切开复位双钢板固定，6例在CT引导下经皮置入松质骨螺钉固定骶髂关节。结果：17例全部恢复行走功能，11例行前路切开骶髂关节双钢板固定患者中骨盆外形恢复好，但1例沿髂嵴切口有不适，6例CT引导下经皮置入骶髂关节螺钉患者骨盆外形接近完全恢复，功能恢复快而满意。结论：骶髂关节骨折脱位患者非手术治疗效果差，宜首选内固定手术治疗；而CT引导下经皮置入骶髂关节螺钉手术操作简单、时间短、出血少、损伤少、固定牢靠，是固定骶髂关节的好方法。     

Reduction and fixation of sacroiliac joint dislocation by the combined use of S1 pedicle screws and the galveston technique

STUDY DESIGN: This retrospective study was designed to analyze the results of the treatment with S1 pedicle screws and the Galveston technique of seven patients with sacroiliac dislocation. OBJECTIVES: To evaluate the effectiveness of the combined use of S1 pedicle screws and the Galveston technique for the treatment of sacroiliac dislocation. SUMMARY OF BACKGROUND DATA: Although several procedures for internal fixation of sacroiliac dislocation have been reported, there have been no reports discussing surgical treatment of sacroiliac dislocation by the combined use of S1 pedicle screws and the Galveston technique. METHODS: Seven patients with sacroiliac dislocation were treated with pedicle screws of S1 and iliac rod according to the Galveston technique. In the seven patients, the dislocation was associated with vertical displacement of the sacroiliac joint and rotational deformity of the pelvic ring. They were classified into Type-C pelvic disruption according to the Tile's classification. Three patients with disruption of the symphysis pubis underwent additional fixation of the symphysis using a dynamic compression plate. The remaining four patients were treated by the posterior procedure alone. RESULTS: The vertical displacement was completely reduced in five patients, and the rotational deformity was completely corrected in four patients. The reduction was maintained at the time of the final follow-up evaluation. There were no perioperative complications with the exception of late infection in one patient. CONCLUSIONS: The combined use of S1 pedicle screws and the Galveston technique provided immediate stability and sufficient reduction for sacroiliac dislocation in seven patients in this study. This hybrid internal fixation procedure is useful for reduction and fixation of sacroiliac dislocation associated with the vertical and rotational instability of the pelvic ring.     

Computed tomography-guided screw fixation of a sacroiliac joint dislocation fracture: a case report

A 19-year-old woman sustained a vertical shear type pelvic fracture. Sacroiliac fixation using computed tomography (CT)-guided cannulated screws was performed for a left sacroiliac dislocation fracture, and a satisfactory result was obtained over time. Patients who have posterior instability of the lateral compression or vertical shear type do not obtain adequate stability by fixation of the anterior part alone; and they often have persistent residual pain, necessitating internal fixation of the posterior part later. Advantages of CT-guided sacroiliac screw fixation include precise evaluation of the degree of reduction and absence of nerve and vascular damage during the time the screw is inserted into the sacral body. This procedure is a useful, safe method owing to its minimal invasiveness in patients with unstable pelvic fractures that are reducible by manual manipulation or traction.     

Anatomically correct reduction and fixation of a Tile C-1 type unilateral sacroiliac disruption using a rod and pedicle screw system between the S1 vertebra and the ilium: experimental and clinical case report

 We have developed a new surgical technique for the treatment of Tile C-1 type sacroiliac disruption. We tried this procedure first in a cadaveric specimen and then applied it to a clinical case. We used the Texas Scottish Rite Hospital (TSRH) rod and pedicle screw system to insert one screw into the S1 vertebra without using an image intensifier and the other screw into the bone marrow of the ilium from the posterosuperior iliac spine. A straight rod was connected between the two screws by using a manipulator to attempt to reduce and fix the sacroiliac disruption. The combined pubic symphysis diastasis could be simultaneously reduced and fixed by using a plate through another incision, resulting in anatomically correct reconstruction of the pelvic ring. In this procedure, the alignment of the sacroiliac joint can be reversibly and directly changed during reduction and fixation. The sacroiliac joint can be strongly fixed because the screws can be freely inserted into the intact portion of the pelvis and the adjacent lumbar spine, if necessary. Good reduction is obtained because direct compression force is applied to the fracture site. The posterior and anterior procedures can be simultaneously performed under the same lateral position. Received: December 25, 2001 / Accepted: May 2, 2002     

Triangular Osteosynthesis for Unstable Sacral Fractures

Objective Stable internal fixation of sacral fractures after anatomic reduction of the vertical displacement. Decompression of nerve roots. Early return to pain-free function. Indications All vertically unstable sacral fractures of type C pelvic ring disruptions. Sacroiliac dislocations. Contraindications Compound fractures. Soft tissue detachment of posterior pelvic ring or fractures associated with considerable soft tissue trauma constitute a contraindication limited to the immediate post-injury phase given the rist of infection and soft tissue complications. Surgical Technique Curvilinear or paravertebral posterior approach. Reduction of the fracture, stabilization between pedicle of L4 or L5 and posterior aspect of the iliac bone or the sacral wing lateral to the sacral fracture. Thereafter, iliosacral screw fixation (unilateral fractures with little displacement) or transsacral plate fixation (bilateral fractures or unilateral fractures with marked displacement). If a stabilization of the anterior pelvic ring has been performed, 1 iliosacral screw is sufficient, otherwise 2 screws should be used. Stabilization of the anterior pelvic ring is only indicated in the presence of disruption of the symphysis, marked displacement of fragments, or if associated injuries necessitate an anterior approach. Results Since April 1992, vertically unstable sacral fractures were treated with this stabilization in 48 patients (average age 34 years, range 15 to 72 years). Since 1994, the start of postoperative full weight-bearing was gradually advanced. Despite the immediate postoperative full weight-bearing, a loss of reduction was not observed in properly performed triangular internal fixation. An incomplete reduction associated with an inadequate stabilization led to a loss of correction in 3 patients. Prominent heads of pedicle screws at the level of the posterior iliac crest may cause soft tissue problems. All fractures consolidated. Implant removal was performed in 23 patients, in 1 patient on accound of deep infection and in 22 after consolidation of the fracture. Out of 25 patients with preoperative neurologic deficit, 4 showed a complete and 3 a partial recovery.     

S1 pediculoiliac screw fixation in instabilities of the sacroiliac complex: biomechanical study and report of two cases

OBJECTIVE: A new technique for posterior sacroiliac fixation is described and compared with conventional techniques. PATIENTS/MATERIAL AND METHODS: A patient with sacral alar fracture (zone 1) and another one with sacroiliac joint instability due to tuberculous infection underwent fixation using screws placed in the S1 pedicle and the iliac bone. Vertical stability of the new technique also was investigated using polyurethane pelvic bone analogs and compared with anterior double plating (group P) and iliosacral screw fixation (group ISS) techniques. RESULTS: Healing was obtained and reduction was maintained in both patients on the final follow-up examination at 2 years postoperatively. Vertical loading tests revealed that failure loads within the first 10 mm of displacement of the new pediculoiliac screw fixation technique (group PIS) was higher than plating (P = 0.03) and lower than ISS techniques (P = 0.002). Ultimate failure load of the PIS technique was slightly higher than plating (P = 0.277) and lower than ISS techniques (P = 0.003). With the addition of an iliosacral screw to the pediculoiliac screw construction (PIS+ISS), the PIS technique became more stable in early (P = 0.110) and ultimate failure loads (P = 0.003). CONCLUSIONS: Pediculoiliac screw fixation for sacroiliac joint disruptions and zone I sacrum fractures using iliac and S1 pedicle screws is a new and effective alternative for obtaining and maintaining anatomic reduction.     

Sacroiliac fixation: a new technique after pelvic trauma

We propose a new technique for sacroiliac fixation for the treatment of pelvic fracture with vertical and horizontal instability (Tile class C). This fixation technique allows control of vertical displacement while allowing, if needed, a certain degree of movement in the horizontal plane to facilitate reduction of anterior lesions. The technique involves insertion of two sacral screws, one in S1 and one in S2, and two iliac screws. The iliac screws are inserted in the posterior iliac crest through two sacroiliac connectors placed on a rod linking the two sacral screws. Vertical displacement is controlled by blocking the screw heads on the connecting rod. If needed, a certain degree of horizontal mobility of the half pelvis can be allowed by loosening the connectors on the rods. This technique was used for 4 patients. Anatomic reduction was achieved and no secondary movement of the osteosynthesis material nor secondary displacement were observed. The quality of the fixation allowed rapid weight bearing in the standing position and early walking without crutches. This type of fixation can only be used for type C12 fractures in the Tile classification.     

Posterior bridging osteosynthesis for traumatic sacroiliac joint dislocation: a report of seven cases

Objective

To evaluate the long-term clinical and radiographic results in patients treated for 61C3-2 (OTA class) pelvic ring disruption with a posterior bridging sacroiliac fixation.

Design

Retrospective clinical and radiological study.

Setting

University Hospital.

Patients/participants

Between May 2002 and March 2003, seven patients with sacroiliac dislocation were treated with a technique developed for the treatment of pelvic injuries with vertical and horizontal instability.

Intervention

We applied spino-pelvic fixation techniques, using spine instrumentation, to stabilize an SI dislocation. This technique consists of two 5 mm diameter screws inserted into the S1 pedicle and S2 ala. A 5.5 mm rod joins the 2 sacral screws to two 7 mm screws placed into the posterior iliac crest and secured into the cancellous mass of the posterior ilium . The described technique stabilizes the SI-joint by performing a bridging osteosynthesis instead of the commonly performed iliosacral screw osteosynthesis passing the SI-joint. Symphyseal platting is performed to reduce and stabilize the anterior ring if necessary.

Main outcome measurements

Data were analyzed as follows: pelvic fracture classification; functional outcome; radiographic outcome; Leg length discrapency; and CT scan aspect of the sacroiliac joint.

Results

Associated pelvic injuries were present in all the patients and include symphysis rupture and acetabular fractures. Four of the seven patients had fractures of the lower extremities. Follow-up was available for all patients at an average of 27 months (range, 32–24 months). Neither septic nor cutaneous complications were reported. No loss of post-op reduction and no fixation failure were observed. The functional results noted at the last examination were satisfactory with a mean Majeed score of 93.

Conclusion

In our opinion, this surgical technique may be indicated in Tile type C1.2 (61C3-2 OTA class) pelvic ring disruption. It obviously reaches its limits in sacral fractures. The technique described provides effective control of vertical displacement while providing a certain degree of horizontal mobility to facilitate reduction and osteosynthesis of anterior lesions. The quality of the fixation allowed early weight bearing.     

Surgical technique of percutaneous iliosacral screw fixation in S3 level in unstable pelvic fracture with closed degloving injury and morrell lavallee lesion: Two case reports

IntroductionPercutaneous screw fixation is considered the best option in unstable pelvic fracture with severe soft tissue injury. However, fixation technique at the level of S3 has not been well established. This paper showed the feasible surgical technique of S3 screw insertion in unstable pelvic fracture with severe soft tissue injury.MethodsWe reported 2 cases of unstable pelvic injury of an 11 years old boy with Marvin-Tile (MT) C1 pelvic fracture with sacroiliac (SI) joint disruption, skin avulsion and Morel-Lavallée lesion. Second case was 30 years old male with open pelvic fracture MTB2 and vertical sacral fracture Denis zone I with Morel-Lavallée lesion, intraperitoneal bladder rupture, infected laparotomy wound dehiscence. We performed percutaneous screws insertion on both pubic rami and IS screw on S1 and S3 to both cases. Functional outcome was evaluated using Majeed and Hannover pelvic score.ResultsAll patients survived and had good reduction with no residual displacement on SI joint. The former case at 21-month follow up presented with excellent outcome (100/100) by Majeed score and very good outcome (4/4) by Hannover score; while the latter case, at 18-month, present with good outcome (85/100) Majeed score and fair outcome (2/4) Hannover score.ConclusionsPercutaneous screw fixation at the level of S3 is feasible and can be inserted in S3 level by sacroiliac type and sacral type with minimal soft tissue intervention and good functional outcome.     

Is there a role for percutaneous pelvic and acetabular reconstruction?

The primary goal in the treatment of pelvic fractures is the restoration of haemodynamic stability. The secondary goal is the reconstruction of stability and symmetry of the pelvic ring. Percutaneous reconstruction can only be accepted if these goals are met. The type of definitive surgery is dependent of the degree of instability of the anterior and posterior pelvic ring. Retrograde transpubic screw fixation of pubic rami fractures is a good alternative to external fixation or plate and screw osteosynthesis. The technique of screw placement and image intensifier control is explained. Internal fixation of pure sacroiliac dislocations, fracture-dislocations of the sacroiliac joint and sacral fractures can be fixed with sacroiliac screws, placed percutaneously. Reduction of the fracture or dislocation is performed closed, or open if anatomy cannot be restored in a closed manner. The primary goal in the treatment of acetabular fractures is to restore anatomy. Reduction comes before fixation. The goal of minimising approaches cannot be more important. In most cases open reduction will be necessary to achieve anatomical reconstruction. Only the experienced acetabular surgeon will be able to decide when and how he can restore anatomy through a less invasive approach or with a percutaneous procedure. The anterior column screw can be inserted through a separate incision in addition to a Kocher-Langenbeck approach. It is the same screw as the retrograde transpubic screw but placed in the opposite direction. The posterior column screw is placed percutaneously from the lateral cortex of the ilium in the direction of the posterior column. Techniques of placement of both screws are demonstrated. Open reduction and internal fixation remains the standard of care in stabilisation of pelvic and acetabular fractures. Only the experienced surgeon will be able to judge if percutaneous procedures can be an alternative or a useful additive to conventional techniques.     

Comparison of the risk of breakage of two kinds of sacroiliac screws in the treatment of bilateral sacral fractures

Purpose

This study aimed at comparing the risk of breakage of lengthened sacroiliac screw and ordinary sacroiliac screw for the treatment of bilateral vertical sacral fractures to provide reference for clinical application.

Methods

A finite element model of type C pelvic ring injury (bilateral type Denis II fracture of sacrum) was produced. The bilateral sacral fractures were fixed with lengthened sacroiliac screw and ordinary sacroiliac screw in seven types of models, respectively. The maximal Von Mises stresses and stress distribution of the two kinds of screws in the case of standing on both feet were measured and compared.

Results

(1) Whether in lengthened sacroiliac screw or ordinary sacroiliac screw, the maximal Von Mises stress of screw fixation only in S1 segment is the largest, and the maximal Von Mises stress of screw fixation only in S2 segment is minor, and the maximal Von Mises stress of screw fixation in S1 and S2 segments, respectively, is the least. (2) When S1 and S2 were both fixed with ordinary screws, the maximal Von Mises stress of screw in S1 segment is larger than that of S2. When S1 and S2 were both fixed with lengthened screws, the maximal Von Mises stress of screw in S1 segment is similar to that of S2. (3) The maximal Von Mises stresses of bilateral symmetrical screws are similar. (4) When only S1 was fixed, the maximal Von Mises stress of lengthened screw is less than that of ordinary screw. When only S2 was fixed, the maximal Von Mises stress of lengthened screw is larger than that of ordinary screw. When S1 and S2 were both fixed, the maximal Von Mises stress of lengthened screw is slightly less than that of ordinary screw. (5) Whether in lengthened screw or ordinary screw, the stress concentrations all exhibited at the regions of screws corresponding to the sacral fracture regions and the part between sacral bilateral fracture lines. Compared with ordinary screw, the stress distribution in lengthened screw is more homogeneous. Whether in lengthened screw or ordinary screw, the stress distribution of only one sacral segment fixation is more concentrated than that of two sacral segments’ fixation. When S1 and S2 were both fixed, the stress distribution of upper screw is more concentrated and that of lower screw is more homogeneous.

Conclusion

In a finite elements simulated type C pelvic ring disruption (bilateral type Denis II sacral fracture), the breakage risk of screws fixed in double-segment bilaterally symmetrically is low, and the breakage risk of screws fixed in S2 segment is lower than that of S1 segment. The bilaterally symmetrical screw fixation in double-segment is strongly recommended to reduce the breakage risk of screws. In addition, the breakage risk of lengthened screws is lower than that of ordinary screws except when screws are fixed in only S2 segment, which merits attention.