Anterior Vertebral Body Height Ratio Research Articles

Percutaneous mesh-container-plasty versus percutaneous kyphoplasty in the treatment of osteoporotic compression fractures with up-endplate injury: a retrospective study

Percutaneous mesh-container-plasty(PMCP), a modified traditional percutaneous kyphoplasty(PKP)technique, is increasingly being used to treat osteoporotic vertebral compression fractures(OVCF) with up-endplate injury. This retrospective study aimed to compare the clinical and radiological results of PKP and PMCP for the treatment of this disease. We retrospectively analyzed the medical records of patients with osteoporotic compression fractures and upper endplate injuries treated at our hospital between January 2019 and December 2021. A total of 192 patients who met the inclusion and exclusion criteria were enrolled. Of these, 103 underwent PKP and 89 underwent PMCP. Key outcome measures included surgical safety, clinical efficacy, and radiological results. Both the PKP and PMCP groups showed significant improvements in VAS (Visual Analog Scale) and ODI (Oswestry Disability Index) scores postoperatively. Additionally, anterior vertebral body height ratio (AVBHr) and Cobb's angle improved in both groups, though no statistically significant difference was observed between them. The hospital stay duration was similar between the two cohorts. Notably, the PMCP group required a larger volume of bone cement injection, yet exhibited a significantly lower incidence of cement leakage and adjacent vertebral fractures (9/89 and 2/89, respectively) compared to the PKP group (24/103 and 11/103, respectively) (p < 0.05). Moreover, the PMCP group had shorter operation times (34.64 ± 9.88 minutes) and reduced fluoroscopy frequency (35.43 ± 5.46 instances) compared to the PKP group (27.23 ± 8.54 minutes and 23.87 ± 5.59 instances, respectively) (p < 0.05). PMCP provided superior clinical outcomes for the management of osteoporotic compression fractures with upper endplate injuries. It was associated with reduced operation and fluoroscopy times, as well as lower risks of adjacent vertebral fractures and cement leakage, compared to PKP.

Percutaneous mesh-container-plasty versus percutaneous kyphoplasty for the treatment of Kümmell's disease: a retrospective cohort study

BackgroundBoth percutaneous kyphoplasty (PKP) and percutaneous mesh-container-plasty (PMCP) were important procedures for the treatment of Kümmell's disease. This study aimed to compare the clinical and radiological results of PKP and PMCP for the treatment of Kümmell's disease.MethodsThis study included patients with Kümmell's disease treated at our center between January 2016 and December 2019. A total of 256 patients were divided into two groups according to the surgical treatment they received. Clinical, radiological, epidemiological, and surgical data were compared between the two groups. Cement leakage, height restoration, deformity correction, and distribution were evaluated. The visual analog scale (VAS), Oswestry Disability Index (ODI), and short-form 36 health survey domains “role-physical” (SF-36 rp) and “bodily pain” (SF-36 bp) were calculated preoperatively, immediately after surgery, and 1-year postoperatively.ResultsThe VAS and ODI scores improved in the PKP [preoperative: 6 (6–7), 68.75 ± 6.64; postoperative: 2 (2–3), 23.25 ± 3.50, respectively] (p < 0.05) and the PMCP [preoperative: 6 (5–7), 67.70 ± 6.50; postoperative: 2 (2–2), 22.24 ± 3.55, respectively] groups (p < 0.05). There were significant differences between the two groups. The mean cost in the PKP group was lower than that in the PMCP group (3697 ± 461 vs. 5255 ± 262 USD, p < 0.05). The cement distribution in the PMCP group was significantly higher than that in the PKP group (41.81 ± 8.82% vs. 33.65 ± 9.24%, p < 0.001). Cement leakage was lower in the PMCP group (23/134) than in the PKP group (35/122) (p < 0.05). The anterior vertebral body height ratio (AVBHr) and Cobb’s angle improved in the PKP (preoperative: 70.85 ± 16.62% and 17.29 ± 9.78°; postoperative: 80.28 ± 13.02% and 13.05 ± 8.40°, respectively) and PMCP (preoperative: 70.96 ± 18.01% and 17.01 ± 10.53°; postoperative: 84.81 ± 12.96% and 10.76 ± 9.23°, respectively) groups (p < 0.05). There were significant differences in vertebral body height recovery and segmental kyphosis improvement between the two groups.ConclusionsPMCP had advantages over PKP in terms of pain relief and functional recovery for the treatment of Kümmell's disease. Moreover, PMCP is more effective than PKP in preventing cement leakage, increasing cement distribution, and improving vertebral height and segmental kyphosis, despite its higher cost.

Correction loss following short-segment posterior fixation for traumatic thoracolumbar burst fractures related to endplate and intervertebral disc destruction

BackgroundThere has been widespread use of short-segment posterior fixation (SSPF) for traumatic thoracolumbar burst fractures. The relationship between the destruction of the vertebral endplate and adjacent disc and postoperative correction loss has been studied in only a few studies. This study investigated the risk factors for correction loss following SSPF.MethodsForty-eight patients (mean age 35.0 years) who underwent SSPF for thoracolumbar burst fractures were enrolled. The mean follow-up period was 25.7 months (12–98 months). The neurological status and postoperative back pain were assessed by the medical records. Segmental kyphotic angle (SKA) and anterior vertebral body height ratio (AVBHR) were measured radiographically to assess indirect vertebral body reduction and local kyphosis. Preoperative Sander’s traumatic intervertebral disc lesion (TIDL) classification and AO classification were used to evaluate the severity of disc and vertebral endplate injury. The corrective loss was considered present if ΔSKA was ≥10°. A multivariate logistic regression analysis was performed to identify the risk factors associated with postoperative loss of correction.ResultsThe fracture distribution was as follows: 10 at T12, 17 at L1, 10 at L2, 9 at L3, and 2 at L4. Vertebral fractures were classified in the following way: A3 in 13 patients, A4 in 11, B1 in 11, and B2 in 13. In 47 patients (98%), a union of the fractured vertebrae was achieved. SKA and AVBHR improved significantly after surgery from 11.6° to 3.5° and from 67.2 to 90.0%, respectively. However, the correction loss at follow-up was 10.4° and 9.7%, respectively. Twenty patients (42%) had severe TIDL (grade 3). Postoperative ΔSKA and ΔAVBHR were significantly higher in patients with TIDL grade 3 than with TIDL grade 0–2. The presence of cranial TIDL grade 3 and older age were significant risk factors for ΔSKA ≥10° on multivariate logistic regression analysis. All patients could walk at follow-up. TIDL grade 3 and ΔSKA ≥10° were associated with severe postoperative back pain.ConclusionsRisk factors for loss of correction after SSPF for thoracolumbar burst fractures were severe disc and endplate destruction at the time of injury and older age.

TREATMENT OF THORACOLUMBAR FRACTURES BY CLOSED REDUCTION VIA A PERCUTANEOUS SOLID PEDICLE SCREW.

Investigate the effect of closed reduction and per- cutaneous pedicle screw fixation in treating thoracolumbar fractures. This retrospective study analyzed 12 cases of single-segment thoracolumbar spine fractures without spinal cord and nerve injury at our department from March 2016 to September 2017. Patients were treated with closed reduction, percutaneous reduction, and internal fixation with solid pedicle screws. The operation time, intraoperative blood loss, anterior vertebral body height ratio (AVHR), Cobb angle (CA) of sagittal kyphosis, and VAS of back pain were determined and statistically compared. The average operation time was 147.2 ± 45.6 min, and the average intraoperative bleeding was 67.8 ± 34.2 mL. All fractured vertebrae were completely reduced, their height was restored, and kyphosis was corrected. The average follow-up period was 10.6 ± 2.7 months, with significant improvements seen in the AVHR, CA of sagittal kyphosis, and VAS score (P < 0.01). One case had a broken rod after three months, and another had a postoperative infection. All the patients achieved bony healing. The treatment of thoracolumbar fractures by closed reduction and internal fixation with a percutaneous solid pedicle screw is simple, effective, and economical. Level of Evidence VI; Therapeutic Study, Case Series .

Effect of cement distribution type on clinical outcome after percutaneous vertebroplasty for osteoporotic vertebral compression fractures in the aging population.

ObjectiveThe study aimed to investigate the effect of the type of bone cement distribution on clinical outcomes following percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCF) in the elderly.MethodsRetrospective analysis of 160 patients diagnosed with OVCF who underwent PVP treatment from March 2018 to December 2020. Based on the kind of postoperative bone cement distribution, bone cement was classified as types I, II, III, IV, and V. Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Cobb angle, anterior vertebral height ratio, refracture rate of injured vertebrae, and incidence of adjacent vertebral fractures were compared for the five types before and after three days, and one year of operation.ResultsVAS and ODI at three days and one year postoperative were significantly lower than those preoperative (P < 0.05) for all five distribution types. VAS and ODI for types I, II, and III were lower at one year postoperatively than for types IV and V (P < 0.05). There was no significant difference in Cobb angle and anterior vertebral body height ratio between preoperative and three days postoperative groups (P < 0.05); however, there were significant differences between three days and one-year postoperative and preoperative groups (P < 0.05). Following one year of surgery, the Cobb angle and the anterior vertebral height ratio of types IV and V were significantly different from those of types I, II, and III (P < 0.05), and there was a statistically significant difference between types IV and V (P < 0.05). In terms of the incidence of injured vertebral refractures and adjacent vertebral fractures, the evenly distributed types I, II, and III were significantly lower than the unevenly distributed types IV and V, and the incidence of type V was higher (P < 0.05).ConclusionsThe clinical efficacy of cement distribution following PVP of types I, II, and III is better than that of types IV and V, which can better relieve pain with long-lasting efficacy and minimize the occurrence of refractures of injured vertebrae and adjacent vertebral body fractures.

Long-segment fixation VS short-segment fixation combined with kyphoplasty for osteoporotic thoracolumbar burst fracture

BackgroundTo retrospectively compare clinical and radiological results of long-segment fixation (LF) and six-screw short-segment fixation combined with kyphoplasty (SSFK) for osteoporotic thoracolumbar burst fracture (OTBF).MethodsForty patients affected by OTBF with mean age of 61.85 years were included in this study. The mean follow-up period was 13.63 months. Twenty-four patients were treated by SSFK, and 16 patients were treated by LF. Clinical outcomes, radiological parameters and complications were assessed and compared.ResultsThe mean operative time and blood loss were 89.71 ± 7.62 min and 143.75 ± 42.51 ml for SSFK group, respectively; 111.69 ± 12.25 min (P < 0.01) and 259.38 ± 49.05 ml (P < 0.01) for LF group, respectively. The two groups were similar in terms of preoperative radiological and clinical results. Compared with preoperative values, both groups achieved significant improvement in terms of VAS, ODI, Cobb angle and anterior vertebral body height (AVH) ratio at final follow-up. However, during the follow-up period, significant loss of Cobb angle and AVH ratio were observed for both groups. Five cases (20.83%) of asymptomatic cement leakage were observed in SSFK group. One case of implant failure and two cases of adjacent or non-adjacent vertebral fractures were observed in LF group.ConclusionsBoth SSFK and LF are safe and effective for treatment of OTBF. Comparatively, SSFK is less invasive and can preserve more motion segments, which may be a more valuable surgical option in some elderly patients. A high-quality randomized controlled study is required to confirm our finding in the future.

Vertebral Body Anterior Translation, a Novel Technique for Delayed Myelopathy Due to Osteoporotic Spine Fractures.

BackgroudOsteoporotic vertebral compression fractures (OVCFs) are often associated with delayed myelopathy. Surgical treatment of delayed myelopathy following an OVCF comprises spinal canal decompression and stable fixation of the vertebral column with an acceptable sagittal alignment. However, such surgical methods are not usually feasible because of medical comorbidities and osteoporosis. We devised a novel, simple technique to decompress the spinal canal and reconstruct the middle column by translating the fractured vertebral body anteriorly through a posterior approach and verified the validity of the new technique.MethodsWe conducted a single-center, retrospective study. Patients who underwent vertebral body anterior translation (VBaT) between 2014 and 2017 due to delayed myelopathy after OVCFs were included. Through a posterior approach, discs between the fractured vertebra and the adjacent vertebrae were released. The fractured vertebra was translated anteriorly with pedicle screws and rods to realign the middle column. Radiological and functional improvement was analyzed.ResultsThere were 12 consecutive patients. The mean age was 70.3 ± 9.4 years. There were 8 female and 4 male patients. Follow-up period was 35.9 ± 13.1 months. Nine patients had pedicle screw augmentation with polymethyl methacrylate. The mean number of fusion segments was 3.4 (range, 2–4). There were 3 types of spinal canal invasion. Five patients had vertebral body vacuum clefts with posterior wall fractures. Five patients had vertebral body angulation with endplate protrusion. Two patients had 3 column fractures. In radiological analysis, the regional kyphotic angle was 35.1° ± 9.1° preoperatively and improved to 8.8° ± 6.8° postoperatively and 9.8° ± 6.1° at the final follow-up (p < 0.001). The anterior vertebral body height ratio was 27.6% ± 7.0% preoperatively and improved to 80.5% ± 13.7% postoperatively and 83.7% ± 12.5% at the final follow-up (p < 0.001). The spinal canal invasion ratio was 52.6% ± 9.1% preoperatively and improved to 25.2% ± 10.4% postoperatively (p < 0.001). Neurological deficit was improved in all patients by 1–3 grades according to Nurick's grading system.ConclusionsIn delayed myelopathy following an OVCF, although the posterior cortex invades the spinal canal, it is usually already in the union state. Therefore, it can bear compression force as a middle column if realigned to be in line with the adjoining vertebrae. VBaT demonstrated satisfactory reduction of kyphosis and maintenance of stability until the last follow-up.

A prospective, international, randomized, noninferiority study comparing an implantable titanium vertebral augmentation device versus balloon kyphoplasty in the reduction of vertebral compression fractures (SAKOS study)

BACKGROUND CONTEXTBalloon kyphoplasty (BKP) is a commonly performed vertebral augmentation procedure for painful osteoporotic vertebral compression fractures (OVCFs). OBJECTIVEThis study aimed to support a non-inferiority finding for the use of a titanium implantable vertebral augmentation device (TIVAD) compared to BKP. STUDY DESIGNProspective, parallel group, controlled comparative randomized study. PATIENT SAMPLEPatients who presented with one or two painful OVCFs located between T7 and L4 aged <3 months, failed conservative treatment, and had an Oswestry Disability Index (ODI) score ≥30/100 were eligible for the study. OUTCOME MEASURESThe primary composite endpoint was defined as: reduction in VCF fracture-related pain at 12 months from baseline and maintenance or functional improvement (ODI) at 12 months from baseline, and absence of device-related adverse event or surgical reintervention. If the primary composite endpoint was successful, a fourth component (absence of adjacent level fracture) was added for analysis. If the analysis of this additional composite endpoint was successful, then midline target height restoration at 6 and 12 months was assessed. Secondary clinical outcomes included back pain intensity, ODI score, EQ-5D index score (range 0=death to 1=full health) and EQ-VAS score (range 0–100). METHODSPatients were recruited in 13 hospitals across 5 countries and were randomly assigned (1:1) to either TIVAD or BKP with electronic randomization as described in the protocol. A total of 152 patients with OVCFs were initially randomized. Eleven patients were excluded (six met exclusion criteria, one with evidence of tumor, and four patients had T score out of requested range). Anterior vertebral body height ratio, midline vertebral body height ratio, and Cobb angle were measured preoperatively and postoperatively by an independent imaging core lab. Adjacent and subsequent fractures and safety parameters were recorded throughout the study. Cement extravasation was evaluated on X-rays. All patients were followed at screening at 5 days, 1 month, 6 months, and 12 months postoperatively. This study was supported by Vexim SA. Seven authors received study-specific support less than $10,000 per year and seven authors received no study-specific support. RESULTSAmong the 141 patients (78.7% female, mean age 73.3±9.5 years) who underwent surgery (TIVAD=68; BKP=73), 126 patients (89.4%) completed the 12-month follow-up period (TIVAD=61; BKP=65). The analysis of primary endpoint on the ITT population demonstrated non-inferiority of the TIVAD to BKP. The analysis of the additional composite endpoint demonstrated the superiority of TIVAD over BKP (p<0.0001) at 6 months (88.1% vs. 60.9%) and at 12 months (79.7% vs. 59.3%). Midline VB height restoration was more improved for TIVAD than for BKP at 6 months (1.14±2.61 mm vs. 0.31±2.22 mm); p=0.0246) and 12 months after surgery (1.31±2.58 mm vs. 0.10±2.34 mm; p=0.0035). No statistically significant differences were shown between procedures for improvement in functional capacity and quality of life. Pain relief was significantly more marked in the TIVAD group compared to the BKP group at 1 month (p=0.029) and at 6 months (p=0.021) after surgery. No patient required surgical reintervention or retreatment at the treated level. No symptomatic cement leakage was reported. Adverse events were similar for both groups (41.2% in the TIVAD group and 45.2% in the BKP group). The incidence of adjacent fractures was significantly lower after the TIVAD procedure than after BKP (12.9% vs. 27.3%; p=0.043). CONCLUSIONSStudy results demonstrated non-inferiority of the TIVAD to the predicate BKP with an excellent risk/benefit profile for results up to 12 months.

Ostéosynthèse segmentaire courte postérieure associée à une vertébroplastie au ciment de sulfate de calcium pour fractures en compression thoraco-lombaire : résultats radiographiques y compris les pseudarthroses et autres complications

ObjectiveTo evaluate the radiographic outcomes of short-segment posterior instrumentation plus vertebroplasty using injectable calcium sulfate cement (CSC) for thoracolumbar compression fractures. Materials and methodsTwenty-eight patients with a single-level thoracolumbar compression fracture, who underwent short-segment pedicle screw fixation and CSC vertebroplasty, were included in the study. The anterior vertebral body height ratio, local kyphosis angle, and the height of the intervertebral disk adjacent to the fractured vertebra were used to evaluate the radiographic results. Complications including bone nonunion, instrument failure, cement leakage, and disc vacuum formation were also assessed. ResultsThe patients were followed up for an average of 24.20±5.40months. The relative preoperative anterior body height was 55.71±15.29%, which improved to 94.93±5.39% immediately after surgery (P<0.001), and at final follow-up showed a 6.50±3.89% loss of height correction (P<0.001). The mean preoperative local kyphosis angle was 22.23±5.65°, which corrected to 2.67±4.43° immediately after surgery (P<0.001), but reverted to 6.71±4.95° at final follow-up, showing a 4.04±1.91° loss of correction (P<0.001). The mean height of the intervertebral disk proximal to the fractured vertebra was 9.87±0.91mm before surgery, 12.53±0.98mm after operation (P<0.001), and the loss of correction at final follow-up was 2.35±1.15mm with a significant difference compared to immediate postoperative values (P<0.001). Bone nonunion occurred in 7 patients, 2 patients had hardware failure, 9 patients had cement leakage, and 10 patients had disc vacuum phenomenon adjacent to the fractured vertebra. ConclusionsThe patients who underwent this procedure had a loss of correction of vertebral height and local kyphosis. Complications such as bone nonunion, instrument failure, cement leakage, and disc vacuum may occur. Rapid CSC resorption accounts for these radiographic outcomes and complications. Level of evidenceLevel IV, retrospective study.

Short-segment posterior instrumentation combined with calcium sulfate cement vertebroplasty for thoracolumbar compression fractures: Radiographic outcomes including nonunion and other complications

ObjectiveTo evaluate the radiographic outcomes of short-segment posterior instrumentation plus vertebroplasty using injectable calcium sulfate cement (CSC) for thoracolumbar compression fractures. Materials and methodsTwenty-eight patients with a single-level thoracolumbar compression fracture, who underwent short-segment pedicle screw fixation and CSC vertebroplasty, were included in the study. The anterior vertebral body height ratio, local kyphosis angle, and the height of the intervertebral disc adjacent to the fractured vertebra were used to evaluate the radiographic results. Complications including bone nonunion, instrument failure, cement leakage, and disc vacuum formation were also assessed. ResultsThe patients were followed up for an average of 24.20±5.40 months. The relative preoperative anterior body height was 55.71±15.29%, which improved to 94.93±5.39% immediately after surgery (P<0.001), and at final follow-up showed a 6.50±3.89% loss of height correction (P<0.001). The mean preoperative local kyphosis angle was 22.23±5.65°, which corrected to 2.67±4.43° immediately after surgery (P<0.001), but reverted to 6.71±4.95° at final follow-up, showing a 4.04±1.91° loss of correction (P<0.001). The mean height of the intervertebral disc proximal to the fractured vertebra was 9.87±0.91mm before surgery, 12.53±0.98mm after operation (P<0.001), and the loss of correction at final follow-up was 2.35±1.15mm with a significant difference compared to immediate postoperative values (P<0.001). Bone nonunion occurred in 7 patients, 2 patients had hardware failure, 9 patients had cement leakage, and 10 patients had disc vacuum phenomenon adjacent to the fractured vertebra. ConclusionsThe patients who underwent this procedure had a loss of correction of vertebral height and local kyphosis. Complications such as bone nonunion, instrument failure, cement leakage, and disc vacuum may occur. Rapid CSC resorption accounts for these radiographic outcomes and complications. Level of evidenceLevel IV, retrospective study.

Balloon kyphoplasty for osteoporotic spinal fractures with middle column compromise

BackgroundBalloon kyphoplasty (BKP) is an effective method for osteoporotic vertebral compression fractures. However osteoporotic spinal fractures with middle column compromise are mentioned as a relative contraindication to BKP. Thus we investigated the safety and efficacy of BKP in the treatment of osteoporotic spinal fractures with middle column compromise but without neurological deficit. MethodsIn this retrospective study, 45 patients who suffered osteoporotic fractures with middle column compromise but without neurological deficits were treated by BKP from May 2007 to December 2010. The final follow-ups were finished during the time of July 2011–September 2011. The mean follow-up period was 20.2 months. The height of the compromised vertebral body, the kyphotic angle and spinal canal compromise were measured before surgery, one day after surgery, and at the final follow-up. A visual analogue scale (VAS) and the Oswestry disability index (ODI) were chosen to evaluate pain and functional activity. ResultsThe mean VAS and ODI scores improved significantly from pre- to post-operation (p<0.05), and this improvement was sustained at the final follow-up. The mean anterior vertebral body height ratio improved from 57.6%±11.8% preoperatively to 86.2%±12.2% postoperatively (p<0.05), so did the mean middle vertebral body height ratio. The kyphotic angle improved from 16.3°±3.7° preoperatively to 9.3°±2.6° postoperatively (p<0.05). At final follow-up, BKP stabilised vertebral height and prevented further kyphotic deformity. While there were no differences in spinal canal compromise between pre-operation and one day after surgery (p>0.05), there was a significant difference from the measurement at the final follow-up (p<0.05). ConclusionBKP is a safe and effective method for osteoporotic spinal fractures with middle column compromise but without neurological deficit. Spontaneous remodelling of the spinal canal also occurs after BKP.

Is Kiva Implant Advantageous to Balloon Kyphoplasty in Treating Osteolytic Metastasis to the Spine? Comparison of 2 Percutaneous Minimal Invasive Spine Techniques

Prospective, parallel-group, controlled, comparative randomized study. To compare cement leakage rate and efficacy for vertebral body restoration of balloon kyphoplasty (BK) versus Kiva novel implant with polymethylmethacrylate (PMMA) for treating osteolytic vertebral body metastasis. Minimally invasively vertebral augmentation techniques with PMMA are mostly performed for treating osteoporotic compression fractures. The Kiva implant with PMMA offers better vertebral body restoration and less PMMA leakage than BK in osteoporotic fractures. No previous study compared leakage rate and efficacy for vertebral body restoration in traditional BK and Kiva with PMMA in osteolytic vertebral body metastases. This study examined 23 patients (71 ± 13 yr) with 41 osteolytic vertebral bodies, who received Kiva with low viscosity PMMA and 24 patients (70 ± 11 yr) with 43 vertebral body osteolyses, who were reinforced with BK and high viscosity PMMA. All osteolyses were graded as Tomita 1 to 3. Anterior vertebral body height ratio (AVBHr), posterior vertebral body height ratio (PVBHr), and middle vertebral body height ratio (MVBHr), Gardner kyphotic deformity, PMMA leakage and were measured and compared between the groups. Visual analogue scale and Oswestry Disability Index were used for functional outcome evaluation. No patient survived after 3 months. Asymptomatic PMMA leakage occurred in 4 (9.3%) vertebrae in the BK group solely (2 to the spinal canal, in Tomita grade 3 osteolysis) Anterior, posterior and middle vertebral body height ratio, Gardner angle improved insignificantly in both groups. Visual anlogue scale and Oswestry Disability Index improved postoperatively similarly in both groups (P < 0.001). BK and Kiva provided equally significant spinal pain relief in patients with cancer with osteolytic metastasis. The absence of cement leakage in the Kiva group and absence of neurological complication in the BK group leakages reflects the safety of both augmentation techniques even in significant osteolysis. The lack of cement leakage in the Kiva cases, although low viscosity PMMA was used, increases this implant safety in augmenting severely destructed thoracolumbar vertebrae and sacrum from osteolytic metastasis. 1.

Posterior short-segment instrumentation without fusion for treatment of thoracolumbar compression fractures

Objective To investigate the clinical effect of posterior short-segment pedicle screw reduction and fixation without fusion in treatment of thoracolumbar mono-segmental compression fractures.Methods Thirty cases of thoracolumbar mono-segmental compression fractures admitted from January 2009 to February 2010 were assigned to single posterior pedicle screw fixation (screw group,n =15) and posterior pedicle screw fixation with posterolateral fusion (fusion group,n =15) according to random number table.Clinical results in the two groups were assessed based on Cobb' s angle,anterior vertebral body height ratio (％) and Oswestry disability index (ODI) before operation,after operation,prior to the removal of implant and at the latest follow-up.Results All the cases were followed up for average 24 months.Both operation time and blood loss were less in screw group than in fusion group [(76.58 ±12.67) min vs (116.29 ± 17.45) min,P ＜ 0.01 ; (287.54 ± 30.76) ml vs (480.34 ± 100.54) ml,P ＜0.01],whereas there were no statistical differences between the two groups in aspects of Cobb' s angle and anterior vertebral body height ratio before and after operation,prior to the removal of implant as well as at the latest follow-up.Moreover,no statistical difference of ODI was noted between the two groups prior to the removal of implant and at the latest follow-up.Conclusion Posterior pedicle screw fixation without bone grafting achieves similar effects with pedicle screw fixation with bone grafting. Key words: Thoracic vertebrae ; Lumbar vertebrae; Internal fixators

Internal fixation plus bone grafting for treatment of thoracolumbar fractures via paraspinal intermuscular approach

Objective To test the safety and effectiveness of transpedicular fixation combined with transpedicular bone grafting via less invasive paraspinal intermusclar approach in treatment of thoracolumbar fractures.Methods The study involved 23 cases of thoracolumbar fractures treated with paraspinal multifidus intramusclular mini-incision,transpedicular bone grafting,and short-segment pedicle screw fixation from June 2009 to June 2012.There were 16 males and 7 females at age of 19-55 years (average 38.8years).Time from injury to surgery varied from 6 hours to 7 days (average 3.2 days).Fracture level was T11 in three cases,T12 in seven,L1 in nine,and L2 in four.According to Denis fracture classification,there were altogether 10 compression fractures and 13 burst fractures.McCormack load sharing classification scored average 5.3.Before operation,anterior vertebral body height ratio was average 58.6％(range,45 ％-73％) and kyphosis angle was average 23.7° (range,15°-34°).Results Operation lasted for average 95.5 minutes (range,75-130 minutes) with intraoperative bleeding of average 160.3 ml (range,115-220 ml).Unilateral incision that was averaged 3.5 cm (range 3.2-4.0 cm) in length obtained primary healing.Average follow-up time was 12.6 months (range,7.5-18 months).Average height of the anterior border was corrected to 97.3％ and average kyphosis angle was corrected to 4.6°.There was neither instrumentation failure nor symptom of persistent postoperative back pain.Conclusions Transpedicular fixation with transpedicular bone grafting via paraspinal muscle approach provides effective recovery of vertebral morphology and correction of kyphotic deformity.Furthermore,the technique gains advantages of easy operation,small trauma,less blood loss and rapid recovery. Key words: Spinal fractures; Thoracic vertebrae; Lumbar vertebrae; Fracture fixation

Balloon Kyphoplasty Versus KIVA Vertebral Augmentation—Comparison of 2 Techniques for Osteoporotic Vertebral Body Fractures

Prospective, parallel-group, controlled comparative randomized study. This study compares the efficacy in sagittal vertebral height and wedge deformity restoration, polymethylmethacrylate cement leakage safety, and functional outcome of balloon kyphoplasty (BK) versus KIVA (a novel vertebral augmentation technique) implant for the augmentation of fresh osteoporotic vertebral body fractures. Minimally invasive vertebral augmentation procedures have been widely used to treat vertebral compression fractures caused by osteoporosis. The results of these trials are encouraging in augmenting the vertebra and reducing the wedge deformity. However, after BK, polymethylmethacrylate leakage remains common after A3.1 AO type fractures, with a frequency per vertebra into the epidural space up to 9.8% but less common (0.03%-5.6%) in A1.1 AO type fracture. KIVA is a novel percutaneous uniportal vertebral augmentation device that is designed to restore the vertebral body and reduce polymethylmethacrylate leakage. From a total 190 patients with osteoporotic fractures who were initially enrolled in this prospective randomized study, 10 patients were excluded (5 met exclusion criteria, 5 with evidence of metastasis). This study examined 82 patients (69 ± 11 yr) with 133 fractures who received KIVA and 86 patients (72 ± 9 yr) with 122 fractures that were reinforced with BK. Anterior (anterior vertebral body height ratio [AVBHr]), midline (midline vertebral body height ratio [MVBHr]), and posterior (posterior vertebral body height ratio [PVBHr]) vertebral body height ratio and Gardner segmental vertebral wedge deformity were measured preoperatively to postoperatively. New fractures were recorded at the final observation. The baseline anthropometric and roentgenographic parameters did not differ between the 2 groups. Any cement leakage was examined on plain roentgenograms and computed tomographic scan. All patients were followed for an average of 14 months (range, 13-15 mo) postoperatively. RESULTS.: At the final observation, both KIVA and BK restored significantly AVBHr, PVBHr, and MVBHr. However, only KIVA device reduced significantly the Gardner angle (P = 0.002). Residual kyphosis of more than 5° was measured significantly more (P < 0.001) in the BK than in KIVA spines. KIVA showed significantly lower (3%, χ2, P ≤ 0.05) leakage) [corrected] (paravertebral, intradiscal) rate per vertebra than BK (0.098%) in which because of intracanal leakage 2 patients developed acute paraplegia and were reoperated in emergency. New fracture rate was similar in both groups. Back pain scores (visual analogue scale), 36-Item Short Form Health Survey (Physical Function and Mental Health domains), and Oswestry Disability Index scores improved significantly in the patients of both groups. Both KIVA and BK restored in short-term similarly vertebral body height, but only KIVA restored vertebral body wedge deformity. KIVA was followed by significantly lower and harmless always extracanal leakage rate than BK. Longer observation is needed to show whether these radiological changes have any functional impact.

Thoracolumbar burst fractures with a neurological deficit treated with posterior decompression and interlaminar fusion

To our knowledge, thoracolumbar burst fractures with a neurological deficit treated with posterior decompression and interlaminar fusion have never been reported. Our study was to assess the outcome of posterior decompression and interlaminar fusion in treating thoracolumbar burst fractures with a neurological deficit. Forty-one patients suffering from thoracolumbar burst fractures with a neurological deficit were included this study. All patients were treated with posterior decompression, interlaminar fusion and short-segment fixation of the vertebrae above and below the fracture level and the fractured vertebrae. All patients were followed up for at least 24months after surgery. Operative time and blood loss averaged 72min and 325ml, respectively. Thirty-eight patients with incomplete neurological lesions improved, by at least one American Spine Injury Association grade, whereas no neurological deterioration was observed in any case. Overall sagittal alignment improved from an average preoperative 22.4°-4.6° kyphosis at the final follow-up observation. The anterior vertebral body height ratio improved from 0.61 before surgery to 0.90 after surgery, whereas posterior vertebral body height ratio improved from 0.90 to 0.95. Spinal canal encroachment was reduced from an average 61.5% before surgery to 8.7% after surgery. Interlaminar radiological fusion was achieved within 6-8months after surgery. No instrumentation failure was found in any patients. Posterior decompression, interlaminar fusion with posterior short-segment fixation provided excellent immediate reduction for traumatic segmental kyphosis and significant spinal canal clearance, and restored vertebral body height in the fracture level in patients with a thoracolumbar burst fracture and associated neurological deficit.

Direct Reduction of Thoracolumbar Burst Fractures by Means of Balloon Kyphoplasty With Calcium Phosphate and Stabilization With Pedicle-Screw Instrumentation and Fusion

Prospective consecutive series. To evaluate the outcomes of the treatment of acute thoracolumbar burst fractures by transpedicular balloon kyphoplasty with calcium phosphate cement and posterior instrumented fusion. In the surgical treatment of thoracolumbar fractures, the major problem after posterior correction and transpedicular instrumentation is failure to support the anterior spinal column, leading to the loss of correction and instrumentation failure. Twenty-three consecutive patients with an average age of 48 years, who sustained thoracolumbar A3-type burst fracture with or without neurologic deficit were included in this prospective study. Twenty-one of 23 patients had single fractures and 2 had each one additional A1 compression contiguous fracture. On admission 5 (26%) of 23 patients had neurologic lesion (5 incomplete, 1 complete). Bilateral transpedicular balloon kyphoplasty was performed with quick hardening calcium phosphate cement to reduce segmental kyphosis and restore vertebral body height and supplementary pedicle-screw instrumentation [long including 4 vertebrae for T9-L1 fractures and short (3 vertebrae) for L2-L4 fractures]. Gardner kyphosis angle, anterior and posterior vertebral body height ratio, and spinal canal encroachment were calculated before to after surgery. All 23 patients were operated within 2 days after admission and were followed for at least 24 months after index surgery. Operating time and blood loss averaged 70 minutes and 250 cc, respectively. The 5 patients with incomplete neurologic lesions improved by at least 1 American Spine Injury Association grade, whereas no neurologic deterioration was observed in any case. Overall sagittal alignment was improved from an average preoperative 16 degrees to 1 degrees kyphosis at final follow-up observation. The anterior vertebral body height ratio improved from 0.6 before surgery to 0.9 (P < 0.001) after surgery, whereas posterior vertebral body height was improved from 0.95 to 1 (P < 0.01). Spinal canal encroachment was reduced from an average 32% before surgery to 20% after surgery. No differences in preoperative values and postoperative changes in radiographic parameters between short and long group were shown. Cement leakage was observed in 4 cases: 3 anterior to vertebral body and 1 into the disc without sequela. In the last computed tomography evaluation, there was shown a continuity between calcium phosphate and cancellous vertebral body bone. Posterolateral radiological fusion was achieved within 6 to 8 months after index operation. There was no instrumentation failure or measurable loss of sagittal curve and vertebral height correction in any group of patients. Balloon kyphoplasty with calcium phosphate cement secured with posterior long and short fixation in the thoracolumbar and lumbar spine, respectively, provided excellent immediate reduction of post-traumatic segmental kyphosis and significant spinal canal clearance and restored vertebral body height in the fracture level in an equal amount both in the short and the long instrumentation.

Treatment of acute thoracolumbar burst fractures with kyphoplasty and short pedicle screw fixation: Transpedicular intracorporeal grafting with calcium phosphate: A prospective study

Background:In the surgical treatment of thoracolumbar fractures, the major problem after posterior correction and transpedicular instrumentation is failure to support the anterior spinal column, leading to loss of correction and instrumentation failure with associated complaints. We conducted this prospective study to evaluate the outcome of the treatment of acute thoracolumbar burst fractures by transpedicular balloon kyphoplasty, grafting with calcium phosphate cement and short pedicle screw fixation plus fusion.Materials and Methods:Twenty-three consecutive patients of thoracolumbar (T9 to L4) burst fracture with or without neurologic deficit with an average age of 43 years, were included in this prospective study. Twenty-one from the 23 patients had single burst fracture while the remaining two patients had a burst fracture and additionally an adjacent A1-type fracture. On admission six (26%) out of 23 patients had neurological deficit (five incomplete, one complete). Bilateral transpedicular balloon kyphoplasty with liquid calcium phosphate to reduce segmental kyphosis and restore vertebral body height and short (three vertebrae) pedicle screw instrumentation with posterolateral fusion was performed. Gardner kyphosis angle, anterior and posterior vertebral body height ratio and spinal canal encroachment were calculated pre- to postoperatively.Results:All 23 patients were operated within two days after admission and were followed for at least 12 months after index surgery. Operating time and blood loss averaged 45 min and 60 cc respectively. The five patients with incomplete neurological lesions improved by at least one ASIA grade, while no neurological deterioration was observed in any case. The VAS and SF-36 (Role physical and Bodily pain domains) were significantly improved postoperatively. Overall sagittal alignment was improved from an average preoperative 16° to one degree kyphosis at final followup observation. The anterior vertebral body height ratio improved from 0.6 preoperatively to 0.9 (P<0.001) postoperatively, while posterior vertebral body height improved from 0.95 to 1 (P<0.01). Spinal canal encroachment was reduced from an average 32% preoperatively to 20% postoperatively. Cement leakage was observed in four cases (three anterior to vertebral body and one into the disc without sequalae). In the last CT evaluation, there was a continuity between calcium phosphate and cancellous vertebral body bone. Posterolateral radiological fusion was achieved within six months after index operation. There was no instrumentation failure or measurable loss of sagittal curve and vertebral height correction in any group of patients.Conclusions:Balloon kyphoplasty with calcium phosphate cement secured with posterior short fixation in the thoracolumbar spine provided excellent immediate reduction of posttraumatic segmental kyphosis and significant spinal canal clearance and restored vertebral body height in the fracture level.