Instrumented ligamentotaxis and stabilization of compression and burst fractures of dorsolumbar and mid-lumbar spines

Usefulness of Percutaneous Pedicle Screw Fixation for Treatment of Lower Lumbar Burst (A3-A4) Fractures: Comparative Study with Thoracolumbar Junction Fractures

Background

Percutaneous pedicle screw fixation (PPSF) without fusion has been recently recommended in the treatment of thoracolumbar fracture to reduce the adverse effects associated with the conventional open approaches and to restore range of motion. However, those studies report on the thoracolumbar junction, and there is no report on lower lumbar fracture.

Purpose

To assess effectiveness of PPSF without fusion for treating lower lumbar burst (A3 and A4) fractures.

Methods

A retrospective analysis was made to evaluate consecutive 50 patients with AO type A3 and A4 thoracolumbar fracture underwent PPSF. Patients were divided into a thoracolumbar junction (TLJ) group (T11-L2) and lower lumbar (LL) group (L3-5). The following items were measured and compared between the two groups. Vertebral height and consolidation, retropulsed fragment, sagittal curve and fixation failure were assessed with certain interval regularly.

Results

The average height at pre- and post-reduction were 56.2% (36.2-74.3), 95.3% (84.2-98.3) in TLJ group and 65.7% (45.7-86.2), 91% (73.1-100) in LL group. The average canal area occupancy rate at pre- and post-reduction were 46.1% (37.4%-67.5%), 38.1% (31.3%-40.8%) in TLJ group and 40.4% (15.0-65.7), 19.3% (9.4-26.6) in LL group. Consolidation was completed within 12 months after surgery in both groups. There was no significant difference between two groups in clinical and radiographic parameters except cobb angle loss.

Conclusion

Patients with lower lumbar fracture can be effectively managed with PPSF without fusion. PPSF following the implant removal can restore the movement of the lower lumbar spine, which is essential for daily life.

In-Fracture Pedicular Screw Placement During Ligamentotaxis Following Traumatic Spine Injuries, a Randomized Clinical Trial on Outcomes

Objective

To investigate the efficacy and safety of two different techniques for spinal ligamentotaxis. Spine ligamentotaxis reduces the number of retropulsed bone fragments in the fractured vertebrae. Two different ligamentotaxis techniques require clinical evaluation.

Methods

This was a randomized clinical trial. The case group was defined as one pedicular screw insertion into a fractured vertebra, and the control group as a no-pedicular screw in the index vertebra. Spine biomechanical values were defined as primary outcomes and complications as secondary outcomes.

Results

A total of 105 patients were enrolled; 23 were excluded for multiple reasons, and the remaining were randomly allocated into the case (n=40) and control (n=42) groups. The patients were followed up and analyzed (n=56). The postoperative mid-sagittal diameter of the vertebral canal (MSD), kyphotic deformity correction, and restoration of the anterior height of the fractured vertebrae showed equal results in both groups. Postoperative retropulsion percentage and pain were significantly lower in the case group than in the control group (p=0.003 and p=0.004, respectively). There were no group preferences for early or long-term postoperative complications.

Conclusions

Regarding clinical and imaging properties, inserting one extra pedicular screw in a fractured vertebra during ligamentotaxis results in better retropulsion reduction and lower postoperative pain.

Re-expansion and Stabilization of Vertebra Plana Fractures Using Bilateral SpineJack® Implants

The surgical treatment of osteoporotic vertebral fractures with greater than 70% collapse, known as "Vertebra Plana (VP)" has been controversial. Originally VP was a considered a contraindication to vertebroplasty or kyphoplasty because of presumed difficulty of entering the collapsed vertebra as well as obtaining significant re-expansion or correct associated sagittal kyphosis. In some cases, multilevel pedicle screw fixation with or without attempts to correct the collapse is still performed to correct the kyphosis or prevent progression. With experience it was clear that the pedicle could be accessed and VP could be treated without added risk of epidural leak of cement or epidural extravasation. Now, with the introduction of newer third-generation intraspinal expansion devices that are larger and need to be placed bilaterally, their use in cases of VP was again an issue since VP cases were excluded from the original multicenter studies used for worldwide approval. This report reviews six cases of VP treated with bilateral SpineJack® implants (Stryker Corp, Kalamazoo, Michigan, USA) demonstrating it is not only feasible to place these larger size implants but achieve significant reconstitution of vertebral height as well as correction of the kyphotic deformity.

Management of Pediatric Posttraumatic Thoracolumbar Vertebral Body Burst Fractures by Use of Single-Stage Posterior Transpedicular Approach

PURPOSE

The posterior transpedicular approach (PTA) is a posterior approach that has the advantage of achieving circumferential arthrodesis by a single posterior-only approach. The purpose of this study was to analyze our experience with PTA in the management of pediatric traumatic thoracolumbar burst fractures (TTLBFs).

METHODS

Consecutive pediatric patients (age ≤18 years) with TTLBFs treated with PTA for 6 years were included in this retrospective study. Correction of kyphotic deformity and change in neurologic status were analyzed to assess outcome. The Cobb angle and American Spinal Injury Association (ASIA) grade were used for this purpose.

RESULTS

There were 6 male and 8 female patients. Five patients had complete injury (ASIA-A), and 9 had incomplete injury. The mean Thoracolumbar Injury Classification and Severity score was 6.71. The mean preoperative Cobb angle was 14.71° and improved to -3.35° postoperatively (mean kyphosis correction -18.05°). Two of the patients experienced iatrogenic nerve root injury. There was 1 postoperative mortality due to complications unrelated to the surgery. The mean Cobb angle was -0.07° at the 32.2-month follow-up visit. Six patients experienced cage subsidence, but none required revision surgery. Postoperatively, 11 (78.5%) patients showed neurologic improvement, and none experienced deterioration. The average ASIA score improved from 2.5 to 3.78. A fusion rate of 100% (n = 12) was observed at the last follow-up visit.

CONCLUSIONS

The present study demonstrates that PTA is a feasible approach in selected pediatric patients with unstable traumatic thoracolumbar burst fractures, with results comparable with those in the adult population. This study demonstrates in detail the procedure, along with the neurologic and radiologic outcomes of this approach in the pediatric population.

Posterior Distraction and Instrumentation Cannot Always Reduce Displaced and Rotated Posterosuperior Fracture Fragments in Thoracolumbar Burst Fracture

STUDY DESIGN

A retrospective clinical study.

OBJECTIVE

To determine the imaging features that can be used to predict failure of reduction of a retropulsed fracture fragment by posterior ligamentotaxis in thoracolumbar burst fractures.

SUMMARY OF BACKGROUND DATA

Posterior instrumentation and distraction with ligamentotaxis has been successfully used to shift retropulsed fragments anteriorly in thoracolumbar burst fractures. However, posterior longitudinal ligament rupture can lead to treatment failure. The exact preoperative radiographical parameters associated with failure of reduction remain unknown.

MATERIALS AND METHODS

A total of 85 patients who suffered from thoracolumbar burst fractures with significant retropulsion of fragments into the spinal canal, as confirmed by preoperative computed tomography and followed by postoperative computed tomography, were retrospectively analyzed. Seventy-three patients (85.9%) in whom the fragments were reduced by ligamentotaxis were included in the reduced group. In 12 patients (14.1%), the fracture fragment in the spinal canal was not reduced, and these patients were included in the nonreduced group. Neurologic status was classified according to the scoring system of the American Spinal Injury Association (ASIA). The displaced distance and rotation angle of the fracture fragment were measured at the fractured segment.

RESULTS

Preoperatively,the average displacement distances into the spinal canal of rotated posterosuperior fragments was 0.53 cm in the reduced group and 0.94 cm in the nonreduced group (P=0.002). The average rotation angles of the fracture fragments were 43.2 degrees in the reduced group and 61.7 degrees in the nonreduced group (P=0.012). "Double cortical surfaces" of the fragment were observed in the nonreduced patients. Neurological function was evaluated and recorded at the 2-year follow-up examination. There was no significant difference in the ASIA recovery grade between the 2 groups (P=0.668).

CONCLUSIONS

Displaced and rotated posterosuperior fracture fragments in thoracolumbar burst fracture cannot always be reduced by posterior ligamentotaxis. The 2 criteria for treatment failure that were most consistently present in our series were a displacement distance greater than 0.85 cm and a rotation angle greater than 55 degrees.

Pure percutaneous pedicle screw fixation without arthrodesis of 32 thoraco-lumbar fractures: clinical and radiological outcome with 36-month follow-up

PURPOSE

To evaluate the outcome of pure percutaneous fixation of unstable single level fractures at the thoraco-lumbar junction (A1 to B2 Magerl/AO Spine).

METHOD

Neurological intact patients were included in a 2-year prospective study (follow-up 36 months). Two groups were considered: the group in which additional short bilateral screws in the fractured vertebra were placed was called lordorizing screw group (LSG), the other was called non lordorizing screw group (nLSG). Clinical outcome was evaluated using the SF-36, the Oswestry disability index and the recovery time needed to go back work. The following radiological parameters were also evaluated on the follow-up exams: the Mid-Sagittal Index, the Cobb's angle and the Sagittal Index.

RESULTS

In the LSG, the correction values of MSI, Cobb's angle and SI were statistically significantly higher than in nLSG.

CONCLUSION

When feasible we recommend a pure percutaneous short segment pedicle screw fixation adding a lordorizing screw.

Freehand thoracic pedicle screw technique using a uniform entry point and sagittal trajectory for all levels: preliminary clinical experience

Object

Experience with freehand thoracic pedicle screw placement is well described in the literature. Published techniques rely on various starting points and trajectories for each level or segment of the thoracic spine. Furthermore, few studies provide specific guidance on sagittal and axial trajectories. The goal of this study was to propose a uniform entry point and sagittal trajectory for all thoracic levels during freehand pedicle screw placement and determine the accuracy of this technique.

Methods

The authors retrospectively reviewed postoperative CT scans of 33 consecutive patients who underwent open, freehand thoracic pedicle-screw fixation using a uniform entry point and sagittal trajectory for all levels. The same entry point for each level was defined as a point 3 mm caudal to the junction of the transverse process and the lateral margin of the superior articulating process, and the sagittal trajectory was always orthogonal to the dorsal curvature of the spine at that level. The medial angulation (axial trajectory) was approximately 30° at T-1 and T-2, and 20° from T-3 to T-12. Breach was defined as greater than 25% of the screw diameter residing outside of the pedicle or vertebral body.

Results

A total of 219 thoracic pedicle screws were placed with a 96% accuracy rate. There were no medial breaches and 9 minor lateral breaches (4.1%). None of the screws had to be repositioned postoperatively, and there were no neurovascular complications associated with the breaches.

Conclusions

It is feasible to place freehand thoracic pedicle screws using a uniform entry point and sagittal trajectory for all levels. The entry point does not have to be adjusted for each level as reported in existing studies, although this technique was not tested in severe scoliotic spines. While other techniques are effective and widely used, this particular method provides more specific parameters and may be easier to learn, teach, and adopt.

The effect of postoperative immobilization on short-segment fixation without bone grafting for unstable fractures of thoracolumbar spine

BACKGROUND

Controversy regarding the fixation level for the management of unstable thoracolumbar spine fractures exists. Often poor results are reported with short-segment fixation. The present study is undertaken to compare the effect of fixation level and variable duration of postoperative immobilization on the outcome of unstable thoracolumbar burst fractures treated by posterior stabilization without bone grafting.

PATIENTS AND METHODS

A randomized, prospective, and consecutive series was conducted at a tertiary level medical center. Thirty-six neurologically intact (Frankel type E) thoracolumbar burst fracture patients admitted at our institute between February 2003 and December 2005 were randomly divided into three groups. Group I (n = 15) and II (n = 11) patients were treated by short-segment fixation, while Group III (n = 10) patients were treated by long-segment fixation. In Group I ambulation was delayed to 10th-14th postoperative day, while group II and III patients were mobilized on third postoperative day. Anterior body height loss (ABHL) percentage and increase in kyphosis as measured by Cobb's angle were calculated preoperatively, postoperatively, and at follow-up. Denis Pain Scale and Work Scales were obtained during follow-up.

RESULTS

Mean follow-up was 13.7 months (range 3-27 months). At the final follow-up the mean ABHL was 4.73% in group I compared with 16.2% in group II and 6.20% in group III. The mean Cobb's angle loss was 1.8 degrees in group I compared with 5.91 degrees in group II and 2.3 degrees in group III. The ABHL difference between groups I and II was significant (P = 0.0002), while between groups I and III was not significant (P = 0.49).

CONCLUSION

The short-segment fixation with amenable delayed ambulation is a valid option for the management of thoracolumbar burst fractures, as radiological results are comparable to that of long-segment fixation with the advantage of preserving maximum number of motion segments.