Transsacral Screw Research Articles

Minimal-invasive Percutaneous Reduction and Transsacral Screw Fixation for U-shaped Fractures

Technical note and case series. To introduce an innovative minimal-invasive surgical procedure reducing surgery time and blood loss in management of U-shaped sacrum fractures. Despite their seldom appearance, U-shaped fractures can cause severe neurological deficits and surgical management difficulties. According to the nature of the injury normally occurring in multi-injured patients after a fall from height, a jump, or road traffic accident, U-shaped fractures create a spinopelvic dissociation and hence are highly unstable. In the past, time-consuming open procedures like large posterior constructs or shortening osteotomies with or without decompression were the method of choice, sacrificing spinal mobility. Insufficient restoration of sacrococcygeal angle and pelvic incidence with conventional techniques may have adverse long-term effects in these patients. In a consecutive series of 3 patients, percutaneous reduction of the fracture with Schanz pins inserted in either the pedicles of L5 or the S1 body and the posterior superior iliac crest was achieved. The Schanz pins act as lever, allowing a good manipulation of the fracture. The reduction is secured by a temporary external fixator to permit optimal restoration of pelvic incidence and sacral kyphosis. Insertion of 2 transsacral screws allow fixation of the restored spinopelvic alignment. Anatomic alignment of the sacrum was possible in each case. Surgery time ranged from 90 to 155 minutes and the blood loss was <50 mL in all 3 cases. Two patients had very good results in the long term regarding maintenance of pelvic incidence and sacrococcygeal angle. One patient with previous cauda equina decompression had loss of correction after 6 months. Percutaneous reduction and transsacral screw fixation offers a less invasive method for treating U-shaped fractures. This can be advantageous in treatment of patients with multiple injuries.

Trans-sacral screw fixation in the treatment of high dyplastic developmental spondylolisthesis

We describe the case of a 67-year-old woman with L5-S1 ontogenetic spondylolisthesis treated with pedicle fixation associated with interbody arthrodesis performed with S1-L5 trans-sacral screwing according to the technique of Bartolozzi. The procedure was followed by a wide decompressive laminectomy. The patient had a progressive improvement of the symptoms which gradually disappeared in 12 mo. The radiograph at 6 and 12 mo showed complete fusion system. The choice of treatment in L5-S1 ontogenetic spondylolithesis is related to a correct clinical and diagnostic planning (X-ray, computer tomography magnetic resonance imaging, Measurement). In particular, the severity index and the square of unstable zone, and the standard measurements already described in the literature, are important to understand and to plane the correct surgical strategy, that require, in most of the times, fusion and interbody artrodesis.

Management of traumatic spinopelvic dissociations: review of the literature.

Spinopelvic dissociation is a rare high-energy injury pattern in adults associated with high morbidity and an increased rate of neurological deficits. The purpose of this article is the conception of fracture type-associated treatment recommendations. This article is based on our own experience with spinopelvic dissociations and a review of the current literature. Bilateral vertical plus an optional transverse fracture component configures spinopelvic dissociations as "U"- or "H"-shaped, with the result of a spinopelvic dissociation. "Y"-, "T"- or "II"-shaped fractures do not necessarily belong to this entity but can be subsumed to this entity in a wider sense. The surgical treatment of these injuries remains challenging. Initial haemodynamic stabilisation represents the main goal of primary care until definitive treatment can be performed. Anatomical reduction is demanding and even more complex in fracture areas with large comminution. Surgical treatment options depend on the fracture type, including transsacral screws, sacral banding and spinopelvic fixation, plus combinations of these procedures. Spinopelvic dissociations remain highly complex injuries. "U"- and "H"-shaped fractures usually require triangular fixation, whereas "II"-, "Y"- and "T"-shaped fractures might be sufficiently stabilised with transsacral screws.

A novel “pelvic ring augmentation construct” for lumbo-pelvic reconstruction in tumour surgery

Reconstructing or augmenting the lumbo-pelvic junction after resection of L5 and part of the sacrum is challenging. Numerous lumbo-pelvic reconstruction methods based on posterior construct and anterior cages have been proposed for cases involving total sacrectomy and lumbar vertebrectomy. These constructs create long lever arms and generate high cantilever forces across the lumbo-sacral junction, resulting in implant failure or breakage. Biomechanical studies have shown that placing implants anterior to lumbo-sacral pivot point provides a more effective moment arm to resist flexion force and improves the ultimate strength of the construct. We present here a novel method to augment a lumbo-pelvic construction using a pelvic ring construct. A 69-year-old lady presented with implant failure of her two previous posterior lumbo-pelvic reconstructions performed by the authors. She initially presented, two and a half years previously with 6 months history of back pain with normal neurological function. MRI scans of her whole spine showed isolated secondaries in the lumbar spine (L4, L5) and sacrum (S1). An abdominal CT scan revealed a primary tumour in her right kidney. Briefly, the first surgery involved a single-stage removal of posterior elements of L4 and L5 and posterior stabilisation from L2 to pelvis, anterior resection of L4 and L5 and partially S1 with implantation of an expandable Synex II cage. The cage was replaced with an anterior rod construct from L2 and L3 to a trans-sacral screw a week later as it had dislodged. The second revision, 9 months later, involved removal of two posterior broken rods which were replaced and converted into a modified four-rod construct. While monitoring her progress, it was subsequently noted that the trans-sacral rod had broken. Therefore, it was decided to augment her lumbo-pelvic construct to prevent eventual catastrophic posterior construct failure. From a posterior approach, contoured rods were passed bilaterally along the inner table of the pelvis under the iliacus muscle up to the anterior border of the pelvis. Using T-connectors, the rods were connected to the posterior lumbo-pelvic construct. Thereafter, two anterior supra-acetabular pelvic screws were connected to a subcutaneously placed rod matched to the shape of the anterior abdominal wall. The pelvic ring construct was completed on connecting this rod with T-connectors to the free ends of the contoured iliac rods. There were no intra-operative complications. At the end of 12 months, she was mobilising with a frame, with no radiological evidence of failure of the construct. However, she died due to disease progression at the end of 15 months. Experience from one clinical case shows that such a construct is feasible and adds a technical option to the difficult reconstruction of lumbo-pelvic junction after tumour surgery.

Transdiscal L5-S1 screws for the treatment of adult spondylolisthesis

The aim of the study was to evaluate clinical and radiographic outcome of patients treated with a modified Grob technique analysing the advantages related to increased mechanical stability. 30 patients that underwent "in situ" fusion for L5-S1 spondylolisthesis were evaluated. All patients presented a low-dysplastic developmental L5-S1 spondylolisthesis. Patients were divided into two groups: A, in which L5-S1 pedicle instrumentation associated with transsacral screw fixation was performed, and B, in which L5-S1 pedicle instrumentation associated with a posterolateral interbody fusion (PLIF) was performed. Patients treated with transdiscal L5-S1 fixation observed a faster resolution of the symptoms and a more rapid return to daily activities, especially at 3-6months' follow-up. The technique is reliable in giving an optimal mechanical stability to obtain a solid fusion. The advantages of this technique are lower incidence of neurologic complications, speed of execution and faster return to normal life.

Locked Transsacral Screw Fixation of Bilateral Injuries of the Posterior Pelvic Ring: Initial Clinical Series

The purpose of this study was to evaluate the clinical safety and efficacy of using a cannulated transsacral screw having a novel locking capability for pelvic fracture fixation. Retrospective analysis of a treatment protocol, patient series. Level I trauma center. Beginning in 2001, 10 patients with bilateral injury to the posterior pelvic ring were treated using a cannulated transsacral screw having a novel locking capability. Patients ranged in age from 21 to 64 years. Follow-up averaged 2 years (range, 1-5 years). Preoperative and postoperative radiographic evaluation included anteroposterior, inlet and outlet pelvic x-rays, and two-dimensional computerized tomography with 3-mm slice thickness. Candidates for this fixation required adequate space estimated on computerized tomography across either the first or second sacral body. Locked transsacral screw fixation of bilateral injuries of the posterior pelvic ring consisting of a long 7.0-mm cannulated screw inserted over a washer from the near ilium, across one sacroiliac joint, through the body of the sacrum, and across the other sacroiliac joint, exiting the far iliac cortex. A self-locking nut was placed on the distal end of the screw. Intraoperative iatrogenic nerve root injuries, postoperative screw position, and maintenance of the fixation construct until fracture healing. There were no iatrogenic nerve injuries. Satisfactory screw position was documented on the postoperative computerized tomography in all cases. Fixation failure did not occur and satisfactory pelvic ring position was maintained in all cases. Locked transsacral screw fixation is a safe and effective technique that should be added to our surgical armamentarium. Indications include bilateral posterior injury as well as any situation in which routine transsacral screw fixation might otherwise be considered such as the presence of pelvic osteopenia or insufficient space for a second point of posterior fixation.

Provocation Lumbar Diskography at Previously Fused Levels

Recurrent or persistent low back pain (LBP) after lumbar fusion can be related to many factors. We reviewed the provocation lumbar diskogram (PLD) features and redo-fusion outcome in our patients evaluated for recurrent/persistent LBP after technically successful fusion. LD was performed in 27 patients with recurrent/persistent LBP after prior successful lumbar surgical fusion (31 fused levels: single-level fusion-23; two-level fusion-4). PLD response and imaging characteristics at fused and non-fused levels were assessed including: intra-diskal lidocaine response, diskogram-image/post-diskogram CT appearance, presence/absence of diskographic contrast leakage, and evidence of fusion integrity or hardware failure. Outcomes in patients having redo-fusion were assessed. Concordant pain was encountered at 15 out of 23 (65%) single-level fusions, non-concordant pain in one fusion with non-painful response in seven. Adjacent-level concordant pain was identified in seven out of 23 (30%) patients (three of 15 with painful fused levels; four of seven with non-painful fusions). In two-level fusions, concordant pain was encountered at one fused level in each patient. In painful fused levels, leaking and contained disks were encountered with partial or complete pain elimination after intra-diskal lidocaine injection. In anterior fusions, space or contrast surrounding the cage was noted at five of 11 levels. Pseudoarthrosis was noted only with trans-sacral screw fusions. Redo-fusion in 13 patients resulted in significant improvement in nine and moderate improvement in one. Patients with recurrent/persistent LBP after technically successful fusion may have a diskogenic pain source at the surgically fused or adjacent level confirmed by lidocaine-assisted PLD.

Can Computer-assisted Surgery Reduce the Effective Dose for Spinal Fusion and Sacroiliac Screw Insertion?

The increasing use of fluoroscopy-based surgical procedures and the associated exposure to radiation raise questions regarding potential risks for patients and operating room personnel. Computer-assisted technologies can help to reduce the emission of radiation; the effect on the patient's dose for the three-dimensional (3-D)-based technologies has not yet been evaluated. We determined the effective and organ dose in dorsal spinal fusion and percutaneous transsacral screw stabilization during conventional fluoroscopy-assisted and computer-navigated procedures. We recorded the dose and duration of radiation from fluoroscopy in 20 patients, with single vertebra fractures of the lumbar spine, who underwent posterior stabilization with and without the use of a navigation system and 20 patients with navigated percutaneous transsacral screw stabilization for sacroiliac joint injuries. For the conventional iliosacral joint operations, the duration of radiation was estimated retrospectively in two cases and further determined from the literature. Dose measurements were performed with a male phantom; the phantom was equipped with thermoluminescence dosimeters. The effective dose in conventional spine surgery using 2-D fluoroscopy was more than 12-fold greater than in navigated operations. For the sacroiliac joint, the effective dose was nearly fivefold greater for nonnavigated operations. Compared with conventional fluoroscopy, the patient's effective dose can be reduced by 3-D computer-assisted spinal and pelvic surgery. Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A Comprehensive Analysis With Minimum 1-Year Follow-up of Vertically Unstable Transforaminal Sacral Fractures Treated With Triangular Osteosynthesis

To analyze the radiographic, clinical, and functional results of triangular osteosynthesis constructs for the treatment of vertically unstable comminuted transforaminal sacral fractures. Level I trauma center. During a 3-year period (July 1, 2003 to June 30, 2006), 58 patients with vertically unstable pelvic injuries were treated with triangular osteosynthesis fixation by a single surgeon at a single institution. Patients were followed-up prospectively as a single cohort, with institutional review board approval. Inclusion criteria for this study were skeletally mature patients with a vertically unstable pelvic ring injury associated with a comminuted transforaminal sacral fracture. Minimum follow-up, both clinically and radiographically, was 1 year. Computed tomography scan was performed on all patients at 6 months to assess healing of the fracture. If the fracture healed, the fixation was removed. Functional outcome was assessed using the Short Form 36, version 2, and short version of Musculoskeletal Functional Assessment questionnaires at 6 months (before fixation removal) and 12 months. Forty of 58 patients with an average age of 39 years were available for a minimum of 1-year follow-up. Wound complications requiring surgical debridement occurred in 5 patients (13%), all of whom had severe soft tissue wounds with internal degloving. Two patients required removal of infected fixation. Iatrogenic L5 nerve injury occurred in 5 patients (13%). Ten patients (25%) had a delayed union on computed tomography scans, and 3 patients had a nonunion as a result of residual fracture gap and incomplete reduction. Six patients (15%) were found to have pronounced tilting of the L5 vertebral body (scoliosis) and distraction of the L5/S1 facet joint ipsilateral to the fixation. This did not correct with removal of the fixation. Failure of the triangular osteosynthesis construct resulting in malunion occurred in 2 patients (5%). All but 2 patients (95%) complained of painful and prominent implants. Functional outcome scoring showed that patients continued to function below the population mean at 1 year but continued to improve, particularly with function and daily activity. Ninety-seven percent of patients returned to some form of work or schooling. Triangular osteosynthesis fixation is a reliable form of fixation that allows early full weight-bearing at 6 weeks while preventing loss of reduction in comminuted vertical shear transforaminal sacral fractures. For this study group, operative reduction was maintained until healing in 95% of patients. However, the 1-year follow-up shows a substantial rate of potential technical problems and complications. Of primary concern were the asymmetric L5 tilting with L5-S1 facet joint distraction and the need for a second surgery in all patients to remove painful fixation. Iatrogenic nerve injury occurred in 5 patients (13%) and is thought to arise secondary to fracture manipulation and reduction. We recommend selective use of this technique for comminuted transforaminal sacral fractures in situations only where reliable iliosacral or trans-sacral screw fixation is not obtainable.

Stabilization of Bilateral Sacroiliac Fracture‐Luxations in Small Animals with a Single Transsacral Screw

Bilateral sacroiliac fracture-luxations in four dogs and four cats weighing 3.5 kg to 30.9 kg were reduced and stabilized with a single 3.5 mm, 4.5 mm, or 6.5 mm transsacral screw. Alignment of the drill bit was visual in six cases and assisted by the use of an aiming device in two cases. Seven animals were reevaluated at months 3 to 6. No significant screw loosening or loss of reduction had occurred. Although no intraoperative complications were encountered with visual drill bit alignment, use of an aiming device for transsacral drilling is strongly recommended.