Long-segment Instrumentation Research Articles

Is It Beneficial to Remove the Pedicle Screw Instrument After Successful Posterior Fusion of Thoracolumbar Burst Fractures?

Case-control study. To investigate the clinical and radiological outcomes of pedicle screw removal after successful fusion of thoracolumbar burst fractures. Implant removal is a common procedure in orthopedic surgery, although the benefits of and indications for removal remain controversial. Previous studies on pedicle screw removal have reported conflicting outcomes, because the study subjects and surgical goals were heterogeneous in nature. We studied 45 consecutive patients who underwent implant removal and a control cohort of 45 age- and sex-matched patients who retained their spinal implants after successful posterior fusion of thoracolumbar burst fractures using pedicle screw instrument. In most cases, long-segment instrumentation with short-segment posterior fusion was performed. The mean elapsed period prior to implant removal after index fracture surgery was 18.3 ± 17.6 months. A visual analogue scale for back pain was applied, the Oswestry disability index calculated, and radiological parameters derived at the time of implant removal and 1 and 2 years postoperatively obtained. These data were compared with those of the control group evaluated at the same times after index fracture surgery. Patient demographics, mechanisms of injury, fracture morphologies, and the outcomes of index fracture surgery were similar between the 2 groups. The mean visual analogue scale and Oswestry disability index scores were better at both the 1- and 2-year follow-ups in the implant removal group than in the control group (all P values = 0.000). The segmental motion angle of the implant removal group was 1.6° ± 1.5° at the time of implant removal, and increased significantly to 5.8° ± 3.9° at 1-year follow-up (P = 0.000), and was maintained at this level at the 2-year follow-up (5.9° ± 4.1°) (P = 0.000). In patients treated successfully for thoracolumbar burst fractures, pedicle screw removal is beneficial because it alleviates pain and disability. Restoration of the segmental motion angle after implant removal may contribute to the clinical improvement. 3.

Vertebroplasty plus short segment pedicle screw fixation in a burst fracture model in cadaveric spines

The current project investigates the role of vertebroplasty in supplementing short segment (SS) posterior instrumentation, only one level above and below a fracture. In the treatment of thoracolumbar burst fractures, long segment (LS) posterior instrumentation two levels above and below the fracture level has been used. In our study, burst fractures were produced at L1 in eight fresh frozen human cadaveric spines. The spines were then tested in three conditions: 1) intact, 2) after LS (T11–L3), 3) SS (T12–L2) instrumentation with pedicle screws and rods, and 4) short segment instrumentation plus cement augmentation of the fracture level (SSC). LS instrumentation was found to significantly reduce the motion at the instrumented level (T12–L2) as well as the levels immediately adjacent in flexion, extension and lateral bending. Similarly, SSC augmentation was found to significantly reduce the motion compared to intact at T12–L2 but still maintained the adjacent level motion. However, SS instrumentation alone did not significantly reduce the motion at T12–L2 except for left lateral bending. While LS instrumentation remains the most stable construct, SS instrumentation augmented with vertebroplasty at the fracture level increases rigidity in flexion, extension and right lateral bending beyond SS instrumentation alone.

Increased Spasticity From a Fracture in the Baclofen Catheter Caused by Charcot Spine: Case Report

In patients with Charcot spine, a loss of normal feedback response from the insensate spine results in spinal neuropathy. Increasing deformity, which can manifest as sitting imbalance, crepitus, or increased back pain, can result. We present the case of a patient with a high-thoracic spinal cord injury (SCI) who subsequently developed a Charcot joint at the T10-11 level that resulted in a dramatic increase in previously controlled spasticity after fracture of an existing baclofen catheter. The 68-year-old man with T4 paraplegia presented with increasing baclofen requirements and radiographic evidence of fracture of the intrathecal baclofen catheter with an associated Charcot joint with extensive bony destruction. The neuropathic spinal arthropathy caused mechanical baclofen catheter malfunction and resulting increased spasticity. The patient was found to have transected both his spinal cord and the baclofen catheter. Treatment consisted of removal of the catheter and stabilization with long-segment instrumentation and fusion from T6 to L2. Follow-up radiographs obtained a year and a half after surgery showed no evidence of hardware failure or significant malalignment. The patient has experienced resolution of symptoms and does not require oral or intrathecal baclofen. This is the only reported case of a Charcot spine causing intrathecal catheter fracture, leading to increased spasticity. This noteworthy case suggests that late spinal instability should be considered in the setting of SCI and increased spasticity.

The significance of removing ruptured intervertebral discs for interbody fusion in treating thoracic or lumbar type B and C spinal injuries through a one-stage posterior approach.

ObjectivesTo identify the negative effect on treatment results of reserving damaged intervertebral discs when treating type B and type C spinal fracture-dislocations through a one-stage posterior approach.MethodsThis is a retrospective review of 53 consecutive patients who were treated in our spine surgery center from January 2005 to May 2012 due to severe thoracolumbar spinal fracture-dislocation. The patients in Group A (24 patients) underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression. In Group B (29 patients), the patients underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression evacuating of the ruptured disc and inserting of a bone graft into the evacuated disc space for interbody fusion. The mean time between injury and operation was 4.1 days (range 2–15 days). The clinical, radiologic and complication outcomes were analyzed retrospectively.ResultsPeriodic follow-ups were carried out until an affirmative union or treatment failure took place. A progressive kyphosis angle larger than 10°, loss of disc height, pseudoarthrosis, recurrence of dislocation or subluxation, or instrument failure before fusion were considered treatment failures. Treatment failures were detected in 13 cases in Group A (failure rate was 54.2%). In Group B, there were 28 cases in which definitive bone fusion was demonstrated on CT scans, and CT scans of the other cases demonstrated undefined pseudoarthrosis without hardware failure. There were statistically significant differences between the two groups (p<0.001 chi-square test). The neurologic recoveries, assessed by the ASIA scoring system, were not satisfactory for the neural deficit patients in either group, indicating there was no significant difference with regard to neurologic recovery between the two groups (p>0.05 Fisher's exact test).ConclusionIntervertebral disc damage is a common characteristic in type B and C spinal fracture-dislocation injuries. The damaged intervertebral disc should be removed and substituted with a bone graft because reserving the damaged disc in situ increases the risk of treatment failure.

Posterior fixation of thoracolumbar burst fractures: Is it possible to protect one segment in the lumbar region?

BackgroundThe treatment for thoracolumbar burst fractures is controversial. The aim of this retrospective study was to compare intermediate-segment (IS) and long-segment (LS) instrumentation in the treatment for these fractures.MethodsIS instrumentation was considered as pedicle fixation two levels above and one level below the fractured vertebra (infra-laminar hooks attached to lower vertebra with pedicle screws). LS instrumentation was done two levels above and two levels below the fractured vertebra. Among a total of 25 consecutive patients, Group 1 included ten patients treated by IS pedicle fixation, whereas Group 2 included fifteen patients treated by LS instrumentation.ResultsThe measurements of local kyphosis (p = 0.955), sagittal index (p = 0.128), anterior vertebral height compression (p = 0.230) and canal diameter expansion (p = 0.839) demonstrated similar improvement at the final follow-up between the two groups. However, there was a significant difference (p < 0.05) between Group 1 and Group 2 regarding clinical outcome [Hannover scoring system, Oswestry disability questionnaire and the range of motion of the lumbar region compared to neutral (0°)].ConclusionsThe radiographic parameters were the same between the two groups. However, the clinical parameters demonstrated that IS instrumentation is a more effective management of thoracolumbar burst fractures.

What do we have to do with Traumatic Thoracolumbar Fractured and Lateral Dislocated Patients without Neurological Deficit?

Thoracolumbar fracture-dislocations usually cause complete neurological dysfunction under the level of trauma. However, a few patients may not have neurological deficits. It’s thought to be responsible for the mechanism of spinal trauma. Aim of surgical treatment is to restore biomechanical stability. In this study we present three traumatic thoracolumbar fracture and lateral dislocation cases without neurological deficit. Both cases had a grade E according to Frankel scale and got 6 points according to Thoracolumbar Injury Classification Severity Scale (TLICS). Patients were treated with long-segment posterior instrumentation via posterior approach. Fracture-dislocation were reducted and stabilized succesfully with posteriror long-segment stabilization via posterior approach. We followed the first patient for 8 months and second patient for 4 years and the third patient for 3 months. Secondary kyphosis deformity didn’t develope in any patients during the follow up. Posterior long-segment stabilization is a safe and efficient treatment for thoracolumbar fracture-dislocation. There has been concern whether the stand-alone posterior surgery can prevent secondary kyphosis deformity in mid-term or long-term follow up or not.

SEGMENTAL SPINAL INSTRUMENTATION IN THE MANAGEMENT OF SCOLIOSIS

Spinal instrumentation for the correction of spinal deformity began with Harrington and his rod system. The use of the Harrington rods was limited, however, because of the need for long-segment instrumentation, distraction, and the potential for hood dislodgment and construct failure. Luque subsequently introduced the next generation of spinal fixation techniques via the concept of segmental instrumentation; his use of sublaminar wires allowed the construct to be fixated to the spine at every level. This arrangement allowed greater control over correction of spinal deformities and significantly lessened the incidence of hardware dislodgment. Modern instrumentation systems, including the use of pedicle screws, permit even greater control of the spine in multiple planes during deformity correction. Newer strategies have decreased the incidence of neurological injury during implant application and provide greater stability. A review of segmental fixation, including surgical techniques, is provided in this article.

P100 Comparison of short- versus long-segment instrumentation after torakolomber burst fractures in terms of gait deviations: a preliminary study

P100 Comparison of short- versus long-segment instrumentation after torakolomber burst fractures in terms of gait deviations: a preliminary study

Posterior Fixation of Thoracolumbar Burst Fracture

The treatment of thoracolumbar burst fracture is a controversial issue. Short-segment (SS) pedicle fixation has become a popular treatment option. However, there are several studies regarding the high rate of failure. The aim of this prospective study was to compare SS versus long-segment (LS) instrumentation. For this purpose, 18 consecutive patients were assigned to two groups. Group 1 included nine patients treated by SS pedicle fixation, whereas group 2 included nine patients treated by LS instrumentation. SS instrumentation was pedicle fixation one level above and below the fractured vertebra. LS instrumentation was hook fixation (claw hooks attached to second upper vertebra and infralaminar hooks attached to first upper vertebra) above and pedicle fixation (pedicle screws attached to first and second lower vertebrae) below the fractured vertebra. As a result, measurements of local kyphosis, sagittal index, and anterior vertebral height compression showed that the LS group had a better outcome at final follow-up (P < 0.05). Also, the SS group had a 55% failure rate, whereas the LS group had prolonged operative time and increased blood loss. However, there was no difference between the two groups according to Low Back Outcome Score. In conclusion, radiographic parameters demonstrated that LS instrumentation is a more effective management of thoracolumbar burst fractures. Nevertheless, clinical outcome was the same between the two groups. However, our conclusions were based on posterior-only surgery. Anterior column support would negate the need for LS fixation. Also, SS would have been more successful if two above and two below pedicle screws were used.