Treatment of Thoracolumbar Type A3 Fractures Using a Percutaneous Intravertebral Expandable Titanium Implant: Long-term Follow-up Results of a Pilot Single Center Study.

BACKGROUND: There are controversies about the optimal management of AO subtype A3 burst fractures. The most common surgical treatment consists of posterior fixation with pedicle screw and rod augmentation. Nevertheless, a loss of correction in height restoration and kyphotic reduction has been observed. OBJECTIVES: The aim of this study was to assess long-term outcomes of a minimally invasive technique using a percutaneous intravertebral expandable titanium implant (PIETI). STUDY DESIGN: This prospective, single center, pilot study was carried out on a consecutive case series of 44 patients with acute (< 2 weeks) traumatic thoracolumbar fractures AO type A3. The average follow-up was 5.6 years. SETTING: A single center in Castilla y Leon, SpainMETHODS: Clinical outcomes (pain intensity on visual analog scale [VAS], Oswestry Disability Index [ODI], analgesic consumption) and radiographic outcomes (anterior/mid/posterior vertebral body height, vertebral area, local kyphosis angle, traumatic regional angulation) were analyzed before surgery, at one month after surgery, and at the end of the follow-up period. RESULTS: At one-month postsurgery, significant improvements in VAS score and ODI score were observed. PIETI achieved significant vertebral body height restoration with median height increases of 2.9 mm/4.3 mm/2.3 mm for anterior/middle/posterior parts, respectively. Significant correction of the local kyphotic angle and improvement of the traumatic regional angulation were accomplished. All these improvements were maintained throughout the follow-up period. The only complication reported was a case of cement leakage. LIMITATIONS: In our opinion, the main limitation of the study is the small number of patients. However, the sample is superior to that shown in other papers. CONCLUSIONS: This study showed that using a PIETI in the treatment of fractures type A3 is a safe and effective method that allows marked clinical improvement, as well as anatomical vertebral body restoration. Unlike with other treatments, results were maintained over time, allowing a better long-term clinical and functional improvement. The rate of cement leakage was lower than other reports.

Requirements for a Stable Long-Term Result in Surgical Reduction of Vertebral Fragility Fractures.

BACKGROUND: Osteoporotic vertebral fractures are one of the major health problems in the world. Minimally invasive surgical treatment has great advantages compared with conservative treatment in treating these fractures, because it eliminates pain and functional disability. The percutaneous intravertebral expandable titanium device SpineJack (Vexim SA, Balma, France) is beneficial compared with other kyphoplasty devices, showing results that are maintained over time and a reduction in complications. However, controversy exists about the minimum amount of cement that should be used to achieve long-term restoration and which is essential to minimize complications. We reviewed publications studying the maintenance of long-term restoration using this percutaneous expandable titanium device in cadavers. In this study, we show the first long-term work with patients treated with percutaneous expandable titanium device, describing precise indications concerning the minimum amount of cement that should be used. METHODS: Results were evaluated from a clinical study including 178 patient outcomes with long-term follow-up results performed by our team. RESULTS: The mean total quantity of cement injected was 4.4 mL (25% vertebral body filling). The leakage rate was 12.9%, and all of these occurrences were asymptomatic. The mean follow-up time was 77 months (60-96 months). All clinical scales improved significantly after the procedure. A recollapse of the treated vertebra was observed in 3 cases (1.6%), and the adjacent fracture rate was 2.2%. CONCLUSIONS: From the results of our study and review of the literature, cement equivalent to 25% of the vertebral body filling volume, when combined with the titanium expandable device, seems to be sufficient to prevent recollapse in osteoporotic and type A.3 fractures.

Intervertebral Disc Repair by Allogeneic Mesenchymal Bone Marrow Cells: A Randomized Controlled Trial.

BACKGROUND: Degenerative disc disease often causes severe low-back pain, a public health problem with huge economic and life quality impact. Chronic cases often require surgery, which may lead to biomechanical problems and accelerated degeneration of the adjacent segments. Autologous mesenchymal stromal cells (MSC) treatments have shown feasibility, safety and strong indications of clinical efficacy. We present here a randomized, controlled trial using allogeneic MSC, which are logistically more convenient than autologous cells. METHODS: We randomized 24 patients with chronic back pain diagnosed with lumbar disk degeneration and unresponsive to conservative treatments into 2 groups. The test group received allogeneic bone marrow MSCs by intradiscal injection of 25 × 10 cells per segment under local anesthesia. The control group received a sham infiltration of paravertebral musculature with the anesthetic. Clinical outcomes were followed up for 1 year and included evaluation of pain, disability, and quality of life. Disc quality was followed up by magnetic resonance imaging. RESULTS: Feasibility and safety were confirmed and indications of clinical efficacy were identified. MSC-treated patients displayed a quick and significant improvement in algofunctional indices versus the controls. This improvement seemed restricted to a group of responders that included 40% of the cohort. Degeneration, quantified by Pfirrmann grading, improved in the MSC-treated patients and worsened in the controls. CONCLUSIONS: Allogeneic MSC therapy may be a valid alternative for the treatment of degenerative disc disease that is more logistically convenient than the autologous MSC treatment. The intervention is simple, does not require surgery, provides pain relief, and significantly improves disc quality.

Risk-benefit analysis of navigation techniques for vertebral transpedicular instrumentation: a prospective study.

BACKGROUND CONTEXT: Pedicle screws in spinal surgery have allowed greater biomechanical stability and higher fusion rates. However, malposition is very common and may cause neurologic, vascular, and visceral injuries and compromise mechanical stability. PURPOSE: The purpose of this study was to compare the malposition rate between intraoperative computed tomography (CT) scan assisted-navigation and free-hand fluoroscopy-guided techniques for placement of pedicle screw instrumentation. STUDY DESIGN/SETTING: This is a prospective, randomized, observational study. PATIENT SAMPLE: A total of 114 patients were included: 58 in the assisted surgery group and 56 in the free-hand fluoroscopy-guided surgery group. OUTCOME MEASURES: Analysis of screw position was assessed using the Heary classification. Breach severity was defined according to the Gertzbein classification. Radiation doses were evaluated using thermoluminescent dosimeters, and estimates of effective and organ doses were made based on scan technical parameters. METHODS: Consecutive patients with degenerative disease, who underwent surgical procedures using the free-hand, or intraoperative navigation technique for placement of transpedicular instrumentation, were included in the study. RESULTS: Forty-four out of 625 implanted screws were malpositioned: 11 (3.6%) in the navigated surgery group and 33 (10.3%) in the free-hand group (p<.001). Screw position according to the Heary scale was Grade II (4 navigated surgery, 6 fluoroscopy guided), Grade III (3 navigated surgery, 11 fluoroscopy guided), Grade IV (4 navigated surgery, 16 fluoroscopy guided), and Grade V (1 fluoroscopy guided). There was only one symptomatic case in the conventional surgery group. Breach severity was seven Grade A and four Grade B in the navigated surgery group, and eight Grade A, 24 Grade B, and one Grade C in free-hand fluoroscopy-guided surgery group. Radiation received per patient was 5.8 mSv (4.8-7.3). The median dose received in the free-hand fluoroscopy group was 1 mGy (0.8-1.1). There was no detectable radiation level in the navigation-assisted surgery group, whereas the effective dose was 10 µGy in the free-hand fluoroscopy-guided surgery group. CONCLUSIONS: Malposition rate, both symptomatic and asymptomatic, in spinal surgery is reduced when using CT-guided placement of transpedicular instrumentation compared with placement under fluoroscopic guidance, with radiation values within the safety limits for health. Larger studies are needed to determine risk-benefit in these patients.