Percutaneous iliosacral screw fixation in S1 and S2 for posterior pelvic ring injuries: technique and perioperative complications

Objective  

Percutaneous iliosacral screw placement allows for minimally invasive fixation of posterior pelvic ring instabilities. The objective of this study was to describe the technique for screws in S1 and S2 using conventional C-arm and to evaluate perioperative complications.     

Removal of an iliosacral screw entrapping the L5 nerve root after failed posterior pelvic ring fixation: a case report

We present a case of a pelvic ring fracture that was originally treated with anterior symphyseal plating and a misplaced percutaneous iliosacral screw. The anterior extraosseus portion of the misplaced 7.3-mm cannulated screw irritated the L5 nerve root, resulting in a radiculopathy. Subsequent surgery involved and mandated removing the bent screw after open identification and protection of the L5 nerve root to avoid further nerve damage; the sacroiliac joint was subsequently debrided and fused. This case represents a complication of acute percutaneous iliosacral screw fixation of pelvic ring injuries and the subsequent strategy for successful salvage.     

Computed tomography-guided fixation of unstable posterior pelvic ring disruptions.

Open reduction and internal fixation (ORIF), the current treatment of choice of posterior pelvic ring disruptions with instability, has significant disadvantages. These include relatively "blind" placement of the fixation screws, infection, exsanguinating hemorrhage, and high wound complication rates. We feel fluoroscopy does not offer significant clarity in defining the posterior structure. Advantages of computed tomography (CT)-guided sacral fixation are direct visualization of the course of the screws and absence of significant wound complications. This technique provides superior visualization of the nerve roots and sacral canal compared to fluoroscopic methods. Thirteen patients (10 unilateral and 3 bilateral) with unstable but reducible sacral fractures or sacroiliac joint (SIJ) disruptions underwent CT-guided posterior pelvic ring fixation using a cannulated screw system. Skeletal traction was required intraoperatively in one case by a traction-counteraction pulley system in the CT scanner. All other reductions were performed by preoperative skeletal traction or manually by the surgeons after anesthesia in the scanner or after push-pull films demonstrated instability. The guide pin, using depth and angulation measurements derived from the scout CT scans, was positioned across the fracture or SIJ. Following CT confirmation of the position of the pin, the screw tract was drilled and the cannulated screw was placed into position. Radiographic and clinical follow-up observation (7-24 months) showed healing with no significant complications in all 13 patients. Computed tomography-guided sacral fixation is a safe alternative to ORIF in selected patients with reducible unstable pelvic fractures.     

Supplemental S1 fixation for type C pelvic ring injuries: biomechanical study of a long iliosacral versus a transsacral screw

Background

A single iliosacral screw placed into the S1 vertebral body has been shown to be clinically unreliable for certain type C pelvic ring injuries. Insertion of a second supplemental iliosacral screw into the S1 or S2 vertebral body has been widely used. However, clinical fixation failures have been reported using this technique, and a supplemental long iliosacral or transsacral screw has been used. The purpose of this study was to compare the biomechanical effect of a supplemental S1 long iliosacral screw versus a transsacral screw in an unstable type C vertically oriented sacral fracture model.

Materials and methods

A type C pelvic ring injury was created in ten osteopenic/osteoporotic cadaver pelves by performing vertical osteotomies through zone 2 of the sacrum and the ipsilateral pubic rami. The sacrum was reduced maintaining a 2-mm fracture gap to simulate a closed-reduction model. All specimens were fixed using one 7.0-mm iliosacral screw into the S1 body. A supplemental long iliosacral screw was placed into the S1 body in five specimens. A supplemental transsacral S1 screw was placed in the other five. Each pelvis underwent 100,000 cycles at 250 N, followed by loading to failure. Vertical displacements at 25,000, 50,000, 75,000, and 100,000 cycles and failure force were recorded.

Results

Vertical displacement increased significantly (p < 0.05) within each group with each increase in the number of cycles. However, there was no statistically significant difference between groups in displacement or load to failure.

Conclusions

Although intuitively a transsacral screw may seem to be better than a long iliosacral screw in conveying additional stability to an unstable sacral fracture fixation construct, we were not able to identify any biomechanical advantage of one method over the other.

Level of evidence

Does not apply—biomechanical study.     

Influence of the inclination angle of the S1 pedicle on screw malposition and operative revision in percutaneous iliosacral screw fixation of posterior pelvic ring fractures

IntroductionDue to aging society, osteoporotic posterior ring fractures of the pelvis are gaining importance. Percutaneous iliosacral screw fixation can reduce pain if conservative therapy is not sufficient. One of the surgical complications is the malposition of the screws in neuroforamen. The aim of this study is to correlate the measured pedicle angle with the screw position in postoperative CT scans.Materials and methodsIn this retrospective study (level of evidence: III), 97 patients with posterior ring fractures were treated with 137 percutaneous iliosacral screws. The inclination angles of the S1 pedicle were measured in the preoperative pelvic CT scan of each patient. Patients were divided up into pedicle angles from 10 – 19.9° (Group 1), 20 – 29.9° (Group 2), 30 – 39.9° (Group 3) and 40 – 49.9° (Group 4). We correlated the pedicle inclination angle to radiologically described screw position in the L5/S1 neuroforamen and the need for revision because of screw malposition.ResultsA total of 10 pedicle inclination angles were from 10 – 19.9° (7.3%), 96 from 20 – 29.9° (70.1%), 28 from 30 – 39.9° (20.4%) and three from 40 – 49.9° (2.2%). Of the 137 screws used, 19 were intraforaminal (13.9%). There were no intraforaminal screws in the Group 1, eight in Group 2, 10 in Group 3 and one in Group 4. Five of the screws needed revision (3,6%). There were no revisions in Groups 1 and 4, two in Group 2 and three in Group 3. Groups 3 and 4 had a higher percentage of intraforaminal screw positions. Patients with steeper angles S1 pedicles showed a significantly higher probability of intraforaminal screw location and revision (p<0.01).DiscussionComplications such as intraforaminal screw position and revision surgery are more frequent in patients with steeper S1 pedicles, making this a detrimental prognostic marker.     

Percutaneous fixation of pelvic ring disruptions

Percutaneous pelvic fixation is possible because intraoperative fluoroscopic imaging and other technologies have been refined. Anterior and posterior unstable pelvic ring disruptions are amenable to percutaneous fixation after closed manipulation or open reduction. Stable and safe fixation is achieved only after an accurate reduction. Anterior pelvic external fixation remains the most common form of percutaneous pelvic fixation; however, percutaneously inserted medullary pubic ramus, transiliac, and iliosacral screws stabilize pelvic disruptions directly while diminishing operative blood loss and operative time. These percutaneous techniques do not decompress the pelvic hematoma allowing early definitive fixation without the risk of additional hemorrhage. Complications associated with open posterior pelvic surgical procedures are similarly avoided by using percutaneous techniques. A thorough knowledge of pelvic osseous anatomy, injury patterns, deformities, and their fluoroscopic correlations are mandatory for percutaneous pelvic fixation to be effective.     

经皮闭合内固定治疗骨盆环损伤

目的对骨盆环损伤闭合内固定术的临床疗效进行评价。方法回顾性分析58例骨盆环损伤患者的临床资料。其中女24例,男34例,年龄18—62岁,平均年龄36岁。全部患者均采用骶髂关节螺钉、耻骨螺钉、耻骨联合螺钉及髂骨后部螺钉等多种形式的闭合内固定。结果58例中满意复位者52例,6例复位不满意;57例骨折愈合,1例骨不连接;56例无血管神经损伤,2例有S1神经损伤,遗留下肢及马鞍麻木。结论经皮闭合固定骨盆环损伤小、出血少、固定效果较好,是一种有前景的手术方式,但对操作者要求高。术前大重量骨牵引有利于术中复位。     

Fixation of posterior pelvic ring disruptions through a posterior approach

Objective  Stable internal screw fixation of posterior pelvic ring disruptions through a posterior approach. Indications  Complete, unstable sacroiliac dislocations with incompetence of anterior and posterior sacroiliac ligaments. Sacroiliac fracture dislocations. Displaced vertical sacral fractures. Contraindications  Damage to posterior soft tissues. Acceptable closed reduction of sacrum or sacroiliac joint. Ipsilateral acetabular fractures treated through an anterior approach. Inadequate intraoperative fluoroscopic visualization of posterior pelvis. Surgical Technique  Vertical paramedian incision overlying the sacroiliac joint. Release of origin of gluteus maximus. Inspection and reduction of sacroiliac joint. Stabilization with iliosacral screws under image intensification. Secure repair of gluteal fascia. Results  107 patients with unstable pelvic ring fractures were treated with open reduction and internal fixation of which 83 had an open reduction of posterior ring injuries. Accuracy of reduction: more than 95% of patients had residual displacement of less than 10 mm. Two patients had a deep wound infection postoperatively. Two-thirds of the patients were able to resume their previous occupation. Pain was either absent or occurred only with strenuous activities. 63% had a normal gait.     

前环皮下内置外固定架联合后环骶髂螺钉治疗不稳定骨盆骨折

目的评估应用前环皮下内置外固定架(internal fixation,INFIX)联合后环骶髂螺钉治疗不稳定骨盆骨折的临床疗效。方法2016年8月-2017年9月,采用前环皮下INFIX联合后环骶髂螺钉治疗不稳定骨盆骨折19例。其中男14例,女5例;年龄17~69岁,平均40.6岁。致伤原因:交通事故伤11例,高处坠落伤5例,重物砸伤3例。骨折根据Tile分型,B1型2例,B2型6例,C型11例。前环损伤包括双侧耻骨坐骨支骨折12例,单侧耻骨坐骨支骨折5例,耻骨联合分离2例;后环损伤包括骶髂韧带损伤2例,单侧髂骨骨折3例,单侧骶骨骨折11例,单侧骶髂关节脱位2例,双侧骶骨骨折1例。受伤至手术时间2~11 d,平均6.1 d。记录术中出血量及手术时间,观察骨折愈合情况及术后并发症情况。采用Matta评分标准评价骨折复位情况,采用Majeed评分标准评估患者术后功能。结果患者手术时间为47~123 min,平均61.4 min;术中出血量为50~115 mL,平均61.1 mL。术后1例发生植钉处切口浅表感染,1例发生单侧股外侧皮神经激惹,经相应处理后治愈或症状消失。无泌尿系统、生殖系统及肠道等损伤。所有患者均获随访,随访时间12~25个月,平均18.1个月。术后骨折均愈合,愈合时间8~13周,平均9.5周;无骨折不愈合、延迟愈合,内固定物松动、断裂等情况发生。2例术前腰骶丛神经损伤患者中,1例功能完全恢复,1例残留轻度跛行症状。末次随访时采用Matta评分标准评价骨折复位情况,获优13例、良6例,优良率100%;采用Majeed评分标准评价功能,获优15例、良4例,优良率100%。结论应用前环皮下INFIX联合后环骶髂螺钉治疗不稳定骨盆骨折临床疗效满意,并发症较少,是一种微创治疗骨盆环损伤的有效方法。     

Results of open reduction internal fixation versus percutaneous iliosacral screw fixation for unstable pelvic ring injuries: retrospective study of 36 patients

European Journal of Orthopaedic Surgery & Traumatology - Surgical stabilization of posterior pelvic ring fractures can be achieved by closed reduction and percutaneous fixation (CRPF) or by...     

Trans-sacral fixation for failed posterior fixation of the pelvic ring

Introduction: In the treatment of certain pelvic ring pathologies (non-unions and failure of ilio-sacral screw fixation) trans-sacral fixation (i.e. fixation from iliac wing to the other traversing the body of S1) may be necessary. The purpose of our study was to describe our early experience and describe the surgical technique. Materials and methods: Seven cases of trans-sacral fixation were identified with a mean patient age of 49-years-old with four females and three males. The diagnosis at the time of trans-sacral fixation was failure of posterior ring fixation in four (three of which had vertical sacral fractures), mal-position of iliosacral (IS) screw in one, failure of fusion of sacroiliac (SI) joint in two. All these cases were augmented with a 4.5 mm reconstruction plate placed in tension posteriorly. Results: At average follow up of 39 months (range 24–75), all patients achieved union. There were no neurological or vascular complications. Two patients required reoperations prior to union. Our current use for this technique is with a 8.0 mm screw (16 mm thread). Conclusions: Initial experience with trans-sacral fixation has proven to be very effective technique to solve the most difficult problems in posterior pelvic ring fixation. We reserve its use to the following indications: nonunion/malunion of the pelvic ring, and sacral fractures.     

Iliosacral screw fixation of the posterior pelvic ring using local anaesthesia and computerised tomography

Various techniques have been used for the fixation of the posterior pelvis, each with disadvantages specific to the technique. In this study, a new protocol involving the placement of posterior pelvic screws in the CT suite is described and evaluated. A total of 66 patients with unstable pelvic ring injuries was stabilised under local anaesthesia with sedation. The mean length of time for the procedure was 26 minutes per screw. There were no technical difficulties or misplaced screws and no cases of infection or nonunion. All patients stated that they would choose to have the CT scan procedure again rather than a procedure requiring general anaesthesia. The charges for the procedure were approximately 1840 pounds sterling (2800 dollars) per operation. CT-guided placement of iliosacral screws is a safe, feasible, and cost-effective alternative to radiologically-guided placement in the operating theatre in selected patients.     

Closed reduction and iliosacral percutaneous fixation of unstable pelvic ring fractures

OBJECTIVE: To report clinical results of patients treated with closed reduction and percutaneous iliosacral screw fixation for unstable pelvic ring fractures. MATERIALS AND METHODS: Retrospective study using medical records, images and late clinical assessment of all patients treated in our centre with percutaneous iliosacral screw fixation for unstable pelvic ring fractures, with a minimum follow-up of 12 months. Seventy-three patients with a mean age of 40.3 years old (range 14-70 years) were treated between July 1998 and December 2005. Seventy-one patients were included. Fractures types included 10 AO type B and 61 AO type C injuries. Forty-two patients had associated injuries. Mean follow-up was 31 months (12-96). Functional status was assessed using Majeed's grading score for pelvic fractures at final follow-up. RESULTS: Sixty-nine patients obtained a satisfactory initial reduction. Two patients had transitory postoperative neurological deficit. Five patients presented hardware failure. Fifteen patients developed sacroiliac osteoarthritis during follow-up. Good and excellent functional results were observed in 66 patients at final follow-up. Five patients had bad results, one due to infection of an anterior pelvic plate and the others due to painful refractory sacroiliac osteoarthritis that required a sacroiliac fusion. Sixty-one (86%) patients were able to return to pre-injury occupation. CONCLUSIONS: Good clinical results with a low and predictable rate of complications can be expected using closed reduction and percutaneous iliosacral screw fixation for unstable pelvic ring fractures.     

Clinical utility of minimally invasive posterior internal fixation within the pelvic ring using S2 alar iliac screws for unstable pelvic ring fracture

IntroductionPosterior internal fixation for unstable pelvic ring fractures is often associated with complications, including pelvic hemorrhage and gluteal necrosis. Pelvic ring fixation using the S2 alar iliac screw (SAIS) without fixation of the lumbosacral vertebrae may have potential as a novel, minimally invasive technique for treating unstable pelvic ring fractures. The present study compared clinical outcomes in patients who underwent SAIS fixation within the pelvic ring with a historical control group of patients who underwent conventional trans-iliac plate fixation for the treatment of unstable pelvic ring fractures.Materials and methodsThirty-two patients diagnosed with unstable pelvic fractures with sacral fracture or sacroiliac joint fracture dislocation were retrospectively evaluated. Eight consecutive patients underwent trans-iliac plate fixation from April 2012 to March 2015, and 24 consecutive patients underwent SAIS fixation from April 2015 to February 2020. Rates of soft tissue complications, intraoperative blood loss, and intraoperative blood transfusion volume were compared in these two groups.ResultsMean intraoperative blood loss was significantly lower in patients who underwent SAIS fixation than in those who underwent trans-iliac plate fixation (141.0 ml vs 315.0 ml; P = 0.027), although there were no between-group differences in intraoperative blood transfusion volume (0.0 ml vs 140 ml; P = 0.105), incidence rate of soft tissue complications (4.2% vs 0%; P = 1.000), and operation time (88.5 min vs 93.0 min; P = 0.862). Bone healing was confirmed in all patients who underwent SAIS fixation without dislocation of the fracture site, whereas one patient who underwent trans-iliac plate fixation experienced a dislocation of the fracture site during follow-up (0% vs 12.5%; P = 0.250).ConclusionsSAIS fixation reduces intraoperative blood loss and ensures bone healing without major complications, including dislocation of the fracture site. SAIS fixation may therefore be an alternative, minimally invasive method of treating unstable pelvic fractures.     

Risk factors for screw breach and iatrogenic nerve injury in percutaneous posterior pelvic ring fixation

BackgroundPercutaneous screw fixation of the posterior pelvic ring is technically demanding and can result in cortical breach. The purpose of this study was to examine risk factors for screw breach and iatrogenic nerve injury.MethodsA retrospective review at a single level-one trauma center identified 245 patients treated with 249 screws for pelvic ring injuries with postoperative computed tomography (CT) scans. Cortical screw breach, iatrogenic nerve injury, and associated risk factors were evaluated.ResultsThere were 86 (35%) breached screws. The breach rate was similar between screw types (33% S1-iliosacral (S1-IS), 44% S1-transsacral (S1-TS), 31% S2-IS, and 30% S2-TS) and was not associated with patient characteristics, Tile C injuries, or corridor size or angle. The overall rate of screw revision for screw malpositioning was 1.2% (3/249). Iatrogenic nerve injuries occurred in 8 (3.2%) of the 249 screws. Screws that caused iatrogenic nerve injuries had greater screw breach distances (5.4 vs. 0 mm, MD 5, CI 2.3 to 8.7, p < 0.0001), were more likely to be S1-IS screws (88% vs. 47%, PD 40%, CI 7 to 58%, p = 0.006), more likely to be placed in Tile C injuries (75% vs. 44%, PD 31%, CI -3 to 55%, p = 0.04), and there was a trend for having a screw corridor size <10 mm (75% vs. 47%, PD 28, CI -6 to 52%, p = 0.06). Of the 7 iatrogenic nerve injuries adjacent to screw breaches, two nerve injuries recovered after screw removal, three recovered with screw retention, and two did not recover with screw retention.ConclusionScrew breaches were common and iatrogenic nerve injuries were more likely with S1-IS screws. Surgeons should maintain a high degree of caution when placing these screws and consider removal of any breached screw associated with nerve injury.     

Early fixation of the vertically unstable pelvis: the role of iliosacral screw fixation of the posterior lesion

OBJECTIVES: To evaluate the effectiveness of the use of iliosacral screw fixation in the management of the vertically unstable pelvis. STUDY DESIGN: Retrospective analysis with clinical follow-up of patients to assess functional outcome. METHODS: Thirty-eight vertically unstable pelvic fractures were treated using iliosacral screw fixation. Anterior fixation was by means of plating in sixteen pelves and by external fixation in fifteen pelves. Four pelves had no anterior fixation. Complications were recorded and radiographs were analyzed to classify fractures and identify screw misplacement and malunion. Twenty-six patients had a functional evaluation. RESULTS: Five patients (13 percent) suffered a pulmonary embolus in the early postoperative period, one of which was fatal, a hospital mortality of 2.6 percent. Screw misplacement occurred in five patients but there were no adverse sequelae. In thirty-four cases with radiographic follow-up, malunion was noted in fifteen cases (44 percent). A lower rate of malunion (36 percent) was noted with internal fixation of the anterior lesion. Of twenty-six patients with long-term follow-up, only four (15 percent) had no pain. Sacroiliac fusion for pain was performed in three patients (11 percent). Twelve patients (46 percent) returned to their preinjury occupation, six patients (23 percent) changed occupation, and nine patients (30 percent) had not yet returned to work by last follow-up. CONCLUSIONS: Iliosacral screw fixation is a useful method of fixation in the vertically unstable pelvis but needs to be augmented by rigid anterior fixation to minimize malunion.     

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.