Vertebral Body Index Research Articles

Percutaneous Screw Distraction for Anatomic Restoration: Case Series.

Percutaneous pedicle screw fixation with distraction reduces morbidity after traumatic thoracolumbar burst fractures; however, there are substantial limitations, particularly for correction of kyphosis. The use of fixed-angle screws may offer improved anatomic restoration, facilitating greater postdistraction vertebral height restoration and spinal canal fragment reduction. We examined the radiographic results of distraction across fixed-angle screws immediately after surgery and in long-term follow-up. Demographic and clinical characteristics were captured for patients with traumatic thoracolumbar fractures undergoing percutaneous pedicle screw fixation by a single surgeon. Radiographic measurements were collected at predistraction, postdistraction, and long-term follow-up time points. Paired t-tests, Student's t-tests, Mann-Whitney U tests, and χ2 tests were used to assess data where appropriate. The case series included 22 patients (77.3% male; mean age 42.0 ± 18.4 years). Hounsfield density consistent with osteopenia was seen in 13.6% of patients at the time of injury. Sporting injuries and motor vehicle accidents were common (both 31.8%). Most injuries occurred at L1 (45.5%). Upon long-term follow-up, the mean injured-level predistraction cross-sectional area improved from 2.1 to 2.9 cm2 (P < .01). Compared with the superadjacent level, the injured-level cross-sectional canal area improved by 28.6% (P < .01). Vertebral body index also improved significantly (18.8° mean change, P < .01). The mean bisegmental Cobb angle improved by 6.2° (P = .01), and injured vertebral body compression decreased by 22.4% (P < .01). Significant improvement in correction was achieved with experience, with final technique yielding superior cross-sectional area (P = .04) and compression ratios (P = .03). Distraction across fixed-angle percutaneous screw instrumentation systems stabilizes traumatic thoracolumbar burst fractures, corrects deformity, and decompresses the spinal canal. Further comparative research is necessary to demonstrate whether outcomes are different between percutaneous instrumentation vs open fusion for thoracolumbar trauma.

A Comparative Study of 2 Techniques to Avoid Bone Cement Loosening and Displacement After Percutaneous Vertebroplasty Treating Unstable Kummell Disease.

Percutaneous vertebroplasty (PVP) is currently the most common surgical procedure for unstable Kummell disease (KD), but cement loosening or displacement often occurs after PVP. We had been using percutaneous pediculoplasty (PPP) or a self-developed bone cement bridging screw system to avoid this severe complication. This study intends to compare these novel surgical procedures through a 2-year follow-up evaluation. From May 2017 to May 2021, 77 patients with single-level unstable KD were included in the PPP group, and 42 patients received the PVP-bone cement bridging screw system were included in the screw group. The changes in the vertebral body index (VBI), bisegmental Cobb angle, visual analogue scale (VAS) and Oswestry Disability Index (ODI) and the cement loosening rate and displacement rate at different follow-up time points were used to evaluate the clinical efficacy. There was no significant difference in VBI or bisegmental Cobb angle between the 2 groups (p > 0.05) before operation, immediately after operation and at 6-month followup, while at 1-year and 2-year postoperative evaluations, the screw group had higher VBI and bisegmental Cobb angle than the PPP group (p < 0.05). Before operation, immediately after operation, at 6-month and 1-year follow-up, there was no significant difference in VAS or ODI score between the 2 groups (p > 0.05), while at 2-year follow-up, the screw group still had higher VAS and ODI scores than the PPP group (p < 0.05). No bone cement displacement occurred in both groups, but the rate of bone cement loosening was 14.29% in group PPP, and 0 in screw group (p < 0.05). This 2-year follow-up study shows that the PVP-bone cement bridging screw system combined therapy had better midterm treatment efficacy than the PVP-PPP combined therapy in patients with unstable KD, and the bone cement bridging screw system is a preferred therapy with better anti cement loosening ability.

Effectiveness of sagittal top compression reduction technique in treatment of thoracolumbar vertebral fractures

To investigate the effectiveness of sagittal top compression reduction technique in the treatment of thoracolumbar vertebral fractures. A retrospective analysis was conducted on the clinical data of 59 patients with thoracolumbar vertebral fractures who met the selection criteria and were admitted between November 2018 and January 2022. Among them, 34 patients were treated with sagittal top compression reduction technique (top pressure group), and 25 patients were treated with traditional reduction technique (traditional group). There was no significant difference in baseline data between the two groups ( P>0.05), including gender, age, fracture segment, cause of injury, AO classification of thoracolumbar vertebral fractures, thoracolumbar injury classification and severity (TLICS) score, American Spinal Injury Association (ASIA) grading, surgical approach, preoperative vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, segmental kyphosis angle, visual analogue scale (VAS) score, and Oswestry disability index (ODI). The operation time, intraoperative blood loss, and incidence of complications between the two groups were recorded and compared. After operation, VAS score and ODI were used to evaluate effectiveness, and X-ray and CT examinations were performed to measure imaging indicators such as vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, and segmental kyphosis angle. There was no significant difference in operation time and intraoperative blood loss between the two groups ( P>0.05). No complication such as dural sac, nerve root, or vascular injury was found during operation, and all incisions healed by first intention. Patients in both groups were followed up 6-48 months, with an average of 20.6 months. No loosening, breakage, or failure of internal fixation occurred during follow-up. The imaging indicators, VAS score, and ODI of the two groups significantly improved at 1 week and last follow-up when compared to preoperative ones ( P<0.05). At last follow-up, the VAS score and ODI further significantly improved when compared to 1 week after operation ( P<0.05). At 1 week after operation and last follow-up, the vertebral body index, segmental kyphosis angle, injured vertebra angle, and ODI in the top pressure group were significantly better than those in the traditional group ( P<0.05). There was no significant difference in VAS score and height ratio of the anterior margin of injured vertebra between the two groups at 1 week after operation ( P>0.05), but the two indicators in the top pressure group were significantly better than those in the traditional group at last follow-up ( P<0.05). The treatment of thoracolumbar vertebral fractures with sagittal top compression reduction technique can significantly improve the quality of vertebral reduction, and is superior to traditional reduction techniques in relieving pain and improving spinal function.

Placement of Percutaneous Screw through pedicle of fractured Vertebrae in fixation of Thoracolumbar spinal fractures - an observational analysis

Aim: To investigate the safety and effectiveness of percutaneous pedicle screw placement at the level of fractured vertebrae in the treatment of thoracolumbar spinal fractures. Methods: The experiment enrolled 40 participants in stages. Percutaneous pedicle screw fixation classified patients into two groups: those who had a fractured vertebra insertion of pedicle screw (fractured group) and those who did not (the "unfractured group") (control group). The duration of the surgery and the volume of blood loss were both documented. In clinical study, both the ODI and the visual analogue scale were utilized (VAS). Cobb angle, vertebral body index (VBI), and anterior vertebral body height were used for radiographic follow-up (CA). Results: The two groups did not differ significantly in terms of operation time and intraoperative blood loss. VAS and ODI scores remained stable across all follow-up periods. In comparison to the control group, the fragmented group exhibited a higher rate of rectification and a lower rate of AVBH and VBI loss. There was no significant difference between the two groups in terms of CA correction and correction loss following surgery. Conclusion: If a patient suffers a type A fracture of the thoracolumbar spine, percutaneous screw fixation combined with intermediate screws may be beneficial in assisting the patient in healing and preserving their vertebral height. Keywords: Thoracolumbar spinal fractures, screw, vertebrae

A novel bone cement screw system combined with vertebroplasty for the treatment of Kummell disease with bone deficiency at the vertebral anterior border: A minimum 3-year follow-up study

ObjectivesWhen vertebroplasty is used to treat Kummell disease with bone deficiency at the vertebral anterior border, bone cement displacement often occurs intraoperatively or postoperatively. We designed and used a new bone cement screw system to avoid this serious complication. The purpose of this study was to evaluate the safety and effectiveness of this novel operation method through more than 3 years of follow-up. Patients and methodsFrom January 2014 to August 2016, 27 patients suffering from single-segment Kummell disease with bone deficiency at the vertebral anterior border were treated by vertebroplasty combined with a novel bone cement screw. Bone cement was released into the diseased vertebrae through the screw to fully fill the intravertebral vacuum cleft. Screw fixation of bone cement can avoid intraoperatively or postoperatively displacement. All patients received surgery involving a unilateral technique, and only one screw was implanted in each patient. The clinical efficacy was evaluated using Odom’s criteria and statistical analysis of the vertebral body index (VBI), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analogue scale (VAS), Oswestry disability index (ODI), and the results of the MOS 36-item short form health survey (SF-36). ResultsThe operation was completed successfully in 27 cases. The average operation time was 49.63 ± 10.82 min, and the average volume of cement injected was 4.70 ± 0.87 mL. The patients’ preoperative VBI, VBA, BCA, VAS and ODI scores were 43.11 ± 5.94, 21.04 ± 2.55, 45.00 ± 6.26, 7.59 ± 0.84, and 79.85 ± 7.58, respectively. The postoperative measurements were 78.70 ± 2.55, 12.70 ± 2.11, 26.11 ± 4.73, 3.22 ± 0.93 and 50.04 ± 9.28, respectively. At the last follow-up, the measurements were 78.04 ± 2.30, 13.15 ± 2.38, 27.07 ± 4.87, 2.04 ± 0.65, and 22.85 ± 5.06, respectively. There was a significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P < 0.05). Comparing the results of SF-36 before operation and at the last follow-up revealed significant differences in physical function, role-physical, body pain, vitality, and social function (P < 0.05). However, there were no significant differences in general health, emotional function and mental health. Finally, 26 patients (96.3 %) had good to excellent clinical outcomes according to Odom's criteria. ConclusionsThis 3-year follow-up study shows that the novel bone cement screw system combined with vertebroplasty has a good short and medium-term therapeutic effect in patients with Kummell disease and bone deficiency at the vertebral anterior border, while its long-term efficacy is subject to further studies.

34. A novel bone cement screw system combined with vertebroplasty for the treatment of Kummell disease with bone deficiency at vertebral anterior border: minimum three-year follow-up study

BACKGROUND CONTEXT When vertebroplasty is used to treat Kummell disease with bone deficiency at vertebral anterior border, bone cement displacement often occurs intraoperative or postoperative. We designed and used a new bone cement screw system to avoid this serious complication. PURPOSE The purpose of this study is to evaluate the safety and effectiveness of this novel operation method through more than 3 years of follow-up. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE A total of 27 patients suffering from single-segment Kummell disease. OUTCOME MEASURES The clinical efficacy was evaluated using Odom's criteria and statistical analysis based on the results of imaging parameters, VAS, ODI and SF-36. METHODS From January 2012 to August 2016, 27 patients suffering from single-segment Kummell disease with bone deficiency at vertebral anterior border were treated by vertebroplasty combined with novel bone cement screw. Bone cement is released into the diseased vertebrae through screw to fully fill the intravertebral vacuum cleft. Screw fixation of bone cement can avoid intraoperative or postoperative displacement. All patients were operated by unilateral technique, only one screw was implanted for each patient. The clinical efficacy was evaluated using Odom's criteria and statistical analysis based on the results of vertebral body index (VBI), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analog scale (VAS), Oswestry Disability Index (ODI), and the MOS 36-item Short Form Health Survey (SF-36). RESULTS The operation was completed successfully in 27 cases. The average operation time was 49.63±10.82 min, and the average volume of cement injected was 4.70±0.87 ml. The patients’ preoperative VBI, VBA, BCA, VAS and ODI scores were 43.11±5.94, 21.04±2.55, 45.00±6.26, 7.59±0.84, and 79.85±7.58, respectively. The postoperative measurements were 78.70±2.55, 12.70±2.11, 26.11±4.73, 3.22±0.93 and 50.04±9.28. At the last follow-up, the measurements were 78.04±2.30, 13.15±2.38, 27.07±4.87, 2.04±0.65, and 22.85±5.06, respectively. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P CONCLUSIONS This 3-year follow-up study shows that the novel bone cement screw system combined with vertebroplasty has a good short and medium-term therapeutic effect on patients with Kummell disease and bone deficiency at vertebral anterior border, while its long-term efficacy is subject to further studies. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Effect of the short-segment internal fixation with intermediate inclined-angle polyaxial screw at the fractured vertebra on the treatment of Denis type B thoracolumbar fracture

BackgroundShort-segment internal fixation with intermediate straight-forward monoaxial screws (SSIF-SFM) and long-segment internal fixation (LSIF) are the two major surgical options for thoracolumbar (TL) fracture. However, SSIF-SFM might not provide adequate support to the spine, and LSIF is unnecessarily extensive. SSIF with intermediate inclined-angle polyxial screw (SSIF-IAP) might offer an alternative solution for the treatment of TL fracture.MethodsA retrospective study was conducted. Sixty-nine patients (47 males and 22 females; average 34.5 years) with Denis type B TL fracture who met the criteria for inclusion were enrolled. Sagittal Cobb’s angle (SCA), anterior vertebral body height (AVBH), vertebral body index (VBI), and spinal canal encroachment (SCE) were measured and assessed. Visual analogue scale (VAS) and Oswestry disability index (ODI) were also evaluated.ResultsThe average values of incision length, blood loss, duration of operation, and hospital stay in the SSIF-IAP group and SSIF-SFM group were significantly decreased compared with those in the LSIF group. The AVBH and VBI in the SSIF-IAP group and LSIF group were significantly improved than those in the SSIF-SFM group at 6-month and the latest follow-ups (P < 0.05). The correction losses of AVBH and VBI (calculated by the reduction of AVBH and VBI) in the SSIF-IAP group and LSIF group were also significantly decreased compared with those in the SSIF-SFM group at 6-month and the latest follow-ups (P < 0.05). There was no significant difference of SCE among the three groups postoperatively. The VAS and ODI in the SSIF-IAP group and SSIF-SFM group were significantly decreased compared with those in the LSIF group at 6-month and the latest follow-ups (P < 0.05).ConclusionBoth SSIF-IAP and LSIF can improve the biomechanical stability as compared with SSIF-SFM. Moreover, SSIF-IAP was less extensive compared to LSIF. SSIF-IAP was an effective and reliable operative technique for patients with Denis type B TL fracture.

The clinical outcomes of percutaneous self-expanding forceful reduction screw system for the treatment of thoracolumbar fracture with severe loss of vertebral height

Objective To explore the safety and effectiveness of a novel percutaneous self-expanding forceful reduction screw system in the treatment of thoracolumbar fracture with severe vertebral height loss. Methods Thirty-eight patients of thoracolumbar fracture with more than 50%vertebral height loss were treated with the novel percutaneous self-expanding forceful reduction screw between March 2014 and June 2015. The screw system is a single plane screw with a reduction angle of 0,3,6,9 degrees. During the operation, the fracture vertebral body was automatically restored during the locking process of the top cap. All the patients were single vertebral fractures. Percutaneous screw fixation and reduction was used in the operation. Two groups of screws were used to fix the two adjacent vertebrae of the injured vertebra and to restore the injured vertebral body, without fusion treatment. The vertebral body index (VBI), height of the anterior margin of fractured vertebra (HAMFV), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analog scale (VAS) and Oswestry disability index (ODI) of the patients before and after operation, 6 months after operation, and at the end of the follow-up were compared. The scoring results were compared using a t test. Results The operation was completed successfully in 38 cases. A total of 152 screws were placed. The accuracy rate of CT evaluation was 98.7%. The average operation time was 90.7±21.9 min, and the average intraoperative bleeding amount was 89.2±31.9 ml. The patients' preoperative VBI, HAMFV, VBA, BCA, VAS and ODI scores were 0.38±0.07, 0.38±0.06, 25.45°±4.54°, 18.66°±8.57°, 7.76±1.02, and 44.58%±2.33%, respectively. The postoperative measurements were 0.93±0.03, 0.95±0.02, 3.71°± 1.35°, 5.84°±6.80 °, 4.29±1.16 and 24.37%±1.88%. At the last follow-up, the measurements were 0.92±0.03, 0.94±0.02, 3.89° ±1.31°,6.05°±7.00°, 1.71±0.65 and 5.95%±2.67%. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P<0.05). Conclusion In the treatment of thoracolumbar fractures with severe loss of vertebral height, the novel percutaneous self-expanding forceful reduction screw system has achieved satisfactory vertebral height restoration and kyphosis correction. Key words: Thoracic vertebrae; Lumbar vertebrae; Spinal fractures; Surgical procedures, minimally invasive; Internal fixators

A novel, percutaneous, self-expanding, forceful reduction screw system for the treatment of thoracolumbar fracture with severe vertebral height loss

BackgroundOver the past decade, the techniques for minimally invasive spinal stabilization have improved significantly. The multiaxial screw utilized in minimally invasive operations is limited in restoring fracture height, reconstructing the anterior vertebral column, and improving kyphosis. Therefore, the percutaneous, minimally invasive approach is not recommended for a thoracolumbar fracture with severe vertebral height loss. We report our novel, percutaneous, self-expanding, forceful reduction screw system to address this problem.MethodsThirty-eight patients experiencing thoracolumbar fracture, with a vertebral height loss more than 50%, were treated with the novel, percutaneous, self-expanding, forceful reduction screw between March 2014 and June 2015. The patients’ charts and radiographs were reviewed. The vertebral body index (VBI), height of the anterior margin of fractured vertebra (HAMFV), vertebral body angle (VBA), bisegmental Cobb angle (BCA), and Oswestry disability index (ODI) scores were obtained before and after the operation, as well as during the 2-year follow-up. The scoring results were compared using t tests.ResultsThe operation was completed successfully in 38 patients. A total of 152 screws were placed. The average operation time was 90.7 ± 21.9 min, and the average intraoperative bleeding amount was 89.2 ± 31.9 ml. The patients were discharged at a mean of 3.2 ± 0.9 postoperative days, with a mean hospital stay of 4.8 ± 1.0 days. The VBI, HAMFV, VBA, and BCA scores were significantly improved after treatment with the novel screw system; there was a significant difference between pre- and postoperative parameters (p < 0.05). Although the decreases in all of the parameters were variable during the 2-year follow-up, there were no statistical differences between the postoperative imaging parameters and the last follow-up imaging parameters (p > 0.05). The ODI score at the last follow-up examination was 5.9 ± 2.7, which was significantly improved compared with the preoperative score of 44.6 ± 2.3 (p < 0.05).ConclusionsWe believe that the novel, percutaneous, self-expanding, forceful reduction screw system developed by us not only successfully expands the minimally invasive percutaneous surgery to the thoracolumbar fracture with severe vertebral height loss but also achieves significant vertebral height restoration and kyphosis correction.

Short segment percutaneous pedicle screw fixation after direct spinal canal decompression in thoracolumbar burst fractures: An alternative option

To investigate the surgical results of percutaneous pedicle screw fixation (PPSF) after spinal canal decompression via a small laminectomy for the treatment of thoracolumbar burst fractures. Twenty-seven patients underwent PPSF after spinal canal decompression via small laminectomies between April 2009 and April 2015. Inclusion criteria consisted of a single-level, closed, thoracolumbar burst fracture and neurological symptoms. Decompression was performed via a small laminectomy, followed by PPSF, including at the level of the fractured vertebra. Cobb angle, vertebral wedge angle, and vertebral body index were each measured from lateral radiographs before and after surgery, and at last follow-up. Neurological assessment was made using the Frankel grading system. The average follow-up period was 26 months. The preoperative average Cobb angle was 15.8° ± 6.6°, and significantly decreased to 6.5° ± 6.2° postoperatively (p < 0.001). Average Cobb angle at last follow-up increased slightly to 8.9° ± 6.9°, but this was not significant (p = 0.112). The preoperative average vertebral wedge angle was 20.6° ± 6.3°, and decreased significantly to 12.2° ± 6.2° postoperatively (p < 0.001). The vertebral body index significantly decreased from 0.58 ± 0.11 to a postoperative value of 0.78 ± 0.10 (p < 0.001). Clinically, no patient deteriorated subsequent to surgery. Percutaneous pedicle screw fixation after spinal canal decompression via small laminectomy provides significant kyphotic correction and improved neurological outcome while offering decreased surgical morbidity. This may be applied as an effective primary surgery in select patients with TLBFs with neurologic symptoms.

Short Percutaneous Posterior Instrumentation: a Reliable Option in the Treatment of Thoraco-lumbar post-traumatic Spinal Fracture

Introduction There are several options to treat instable thoraco-lumbar spinal fractures without spinal cord involvement. A short percutaneous posterior instrumentation [SPPI] (i.e., involving only one level up and one level below the lesioned level) is a fast choice, safer than other more invasive options at the cost of an apparent less efficacy in restoring proper alignment or in the ability to maintain good results in the long term. Aim of our present contribution is to report the incidence of worsening during time of spinal alignment features in patients treated with SPPI. Material and Methods Between September 2010 and August 2015, among 230 consecutive operations for instable post-traumatic thoraco-lumbar spinal fractures, we performed 47 SPPI and 130 other percutaneous instrumentations (4 levels or more). Fractures were defined according to the AO classification; vertebral body index [VBI], vertebral body angle [VBA] and Cobb's angle [CA] were measured before, immediately after operation (i.e., in the first two post-op days) at 1 month- and at 12 month-follow-up. All data were drawn from multi-slice high-definition CT-scans. Local ethical committee approved the study design. Results were also stratified according to the class of fracture and number of blocked levels (3, 4 or more). Results In the SPPI-cases we found preop the following mean values: VBI 0,67, VBA -16,5, CA -9,5; at 12 months follow-up (26 patients out of 35) mean values were: VBI 0,84,VBA -14,8 and CA -5,4 with changes statistically non significant between immediate post-op and 1 year follow-up. Conclusion In our hands SPPI proved to be an effective therapeutic option. No significant kyphotic worsening was observed during the first year post-op. Parallel sections of the present study and prolongement of the observational time will allow us to compare SPPI with longer posterior instrumentations in non spinal cord-lesioned thoraco-lumbar fractured patients.

Effect of the percutaneous pedicle screw fixation at the fractured vertebra on the treatment of thoracolumbar fractures.

The purpose of this study was to evaluate the efficacy and safety of percutaneous pedicle screw fixation at the fractured vertebra in the treatment of thoracolumbar fractures. Thirty-two consecutive patients were enrolled in the study. All patients received percutaneous pedicle screw fixation, and they were randomly divided into two groups to undergo either the placement of pedicle screws into the fractured vertebra (fractured group) or not (control group). The operation time and intra-operative blood loss were recorded. Oswestry disability index (ODI) questionnaire and visual analogue scale (VAS) as clinical assessments were quantified. Radiographic follow-up was defined by the vertebral body index (VBI), anterior vertebral body height (AVBH), and Cobb angle (CA). No significant difference was observed in the operation time and intra-operative blood loss between the two groups. Clinical results (VAS and ODI scores) showed no significant difference during all the follow-up periods. In the fractured group, there were better correction and less loss of AVBH and VBI compared with the control group. However, post-operative correction of the CA immediately after surgery and the correction loss at the final follow-up showed no significant difference between the two groups. Percutaneous screw fixation combined with intermediate screws at the fractured vertebra could more effectively restore and maintain fractured vertebral height, and is an acceptable, minimally invasive surgical choice for patients with type A thoracolumbar fractures.

Neuronavigated Percutaneous Treatment of Thoracolumbar Spine Fractures

Introduction Treatment goals of amielic thoracolumbar spine fractures are the stabilization of traumatized segment, possibly restoring the physiological spine curvature, and vertebral healing or fusion of the affected segment. Percutaneous minimally invasive techniques are becoming a viable option in the treatment of selected thoracolumbar fractures; intraoperative neuronavigation of biplanar fluoroscopy associated with preoperative CT scan allows precise pedicle insertion and reduces intraoperative X-ray exposure. Materials and Methods Over a period of 2 years, 43 patients with thoracolumbar fractures at our institution were elected for minimally invasive surgery using neuronavigated technique. All patients experienced one or two thoracolumbar fractures (varying from A3.1 to B2.3, according to the AO/Magerl classification) without neurological deficits. Pain profile was assessed by visual analog scale (VAS) and all radiological findings were evaluated with vertebral body index (VBI), vertebral body angle (VBA), and Cobb angle. Procedures used for treatment include kyphoplasty alone and short segment percutaneous pedicle screw fixation with or without vertebral body augmentation. All the procedures were performed under general anesthesia, but for collaborating patients who need kyphoplasty analgosedation was used. Clinical mean follow-up was 15 months (2–24 months) and has been assessed with VAS and the ability to return to their original lifestyle and/or occupation; radiographic postoperative evaluation consisted of X-ray for kyphoplasty patients and CT for those instrumented to determine the accuracy of screw placement. Results The mean surgical duration was 92 minutes (passing from 32 minutes for the fastest kyphoplasty to 170 minutes for the slowest fixation). There was no case of screw or needle malposition during kyphoplasty. Total radiation exposure was 54 seconds. Postoperatively, almost all the patients improved their symptoms and nobody needed reoperation because of postoperative complications, except for a case in which an initial screw pull-out was stopped with a second stage kyphoplasty. Conclusion Neuronavigation in minimally invasive spine surgery represents a viable solution for the treatment of amielic thoracolumbar fractures. Minimal invasive techniques have been shown to reduce blood loss, postoperative pain, and hospitalization; with the neuronavigated support, there is also a sensible reduction in X-ray exposure of patients and operative room operators.

Treatment of thoracolumbar trauma by short-segment percutaneous transpedicular screw instrumentation: prospective comparative study with a minimum 2-year follow-up

The main aim of this study was to compare clinical and radiological outcomes after stabilization by a percutaneous transpedicular system and stabilization from the standard open approach for thoracolumbar spine injury. Thirty-seven consecutive patients were enrolled in the study over a period of 16 months. Patients were included in the study if they experienced 1 thoracolumbar fracture (A3.1-A3.3, according to the AO/Magerl classification), had an absence of neurological deficits, had no other significant injuries, and were willing to participate. Eighteen patients were treated by short-segment, minimally invasive, percutaneous pedicle screw instrumentation. The control group was composed of 19 patients who were stabilized using a short-segment transpedicular construct, which was performed through a standard midline incision. The pain profile was assessed by a visual analog scale (VAS), and overall satisfaction by a simple 4-stage scale relating to performance of daily activities. Working ability and return to original occupation were also monitored. Radiographic follow-up was defined by the vertebral body index (VBI), vertebral body angle (VBA), and bisegmental Cobb angle. The accuracy of screw placement was examined using CT. The mean surgical duration in the percutaneous screw group was 53 ± 10 minutes, compared with 60 ± 9 minutes in the control group (p = 0.032). The percutaneous screw group had a significantly lower perioperative blood loss of 56 ± 17 ml, compared with 331 ± 149 ml in the control group (p < 0.001). Scores on the VAS in patients in the percutaneous screw group during the first 7 postoperative days were significantly lower than those in the control group (p < 0.001). There was no significant difference between groups in VBI, VBA, and Cobb angle values during follow-up. There was no significant difference in screw placement accuracy between the groups and no patients required surgical revision. There was no significant difference between groups in overall satisfaction at the 2-year follow-up (p = 0.402). Working ability was insignificantly better in the percutaneous screw group; previous working position was achieved in 17 patients in this group and in 12 cases in the control group (p = 0.088). This study confirms that the percutaneous transpedicular screw technique represents a viable option in the treatment of preselected thoracolumbar fractures. A significant reduction in blood loss, postoperative pain, and surgical time were the main advantages associated with this minimally invasive technique. Clinical, functional, and radiological results were at least the same as those achieved using the open technique after a 2-year follow-up. The short-term benefits of the percutaneous transpedicular screw technique are apparent, and long-term results have to be studied in other well-designed studies evaluating the theoretical benefit of the percutaneous technique and assessing whether the results of the latter are as durable as the ones achieved by open surgery.

Risk of progression of degenerative lumbar scoliosis

In this paper the authors' goal was to determine the factors associated with the progression of degenerative lumbar scoliosis (DLS). Twenty-seven patients (3 men and 24 women; mean age 64.9 years) with more than 10° of lumbar scoliosis at baseline were monitored for a mean period of 10 years. The radiological evaluation included measurement of the scoliosis angle using the Cobb method, the direction of the scoliosis, the relationship between the intercrest line and the L-5 vertebra, lateral listhesis, segmental angle, distance from the center of the sacral line to the apical vertebra, degenerative listhesis anteriorly or posteriorly or both, and lordosis angle. In addition, the lateral osteophyte difference, disc index, and severity of osteoporosis were measured. The pain and disability outcomes were assessed using the visual analog scale and the Oswestry Disability Index (ODI) relative to severity of the angle of scoliosis. The mean initial and final scoliosis angles were 14° ± 5.4° and 25° ± 8.5°, respectively. The initial disc index at the L-3 vertebra (Spearman ρ = 0.7, p < 0.001), the sum of the segmental wedging angles above and below the L-3 vertebra (ρ = 0.6, p < 0.001), and the initial disc index at the apical vertebra (ρ = 0.6, p < 0.001) were correlated with the last follow-up angle of the scoliosis. By contrast, there was no statistically significant correlation between the initial segmental angles at L2-3 and L3-4 and the final follow-up scoliosis angle (ρ = 0.2, p = 0.67; and ρ = 0.1, p = 0.22; respectively). When the authors separated the patients into 3 groups according to the sum of the segmental angles above and below L-3 (< 5°, 5° to 10°, and > 10°), they found that 3 (42.9%) of 7, 8 (66.7%) of 12, and 6 (75.0%) of 8 patients in the 3 groups showed increases of greater than 10° in scoliosis angle. The mean distance from the center of the sacral line to the apical vertebra was 36.0 ± 9.7 mm, and the distance correlated with the measurement of the last follow-up angle of the scoliosis (ρ = 0.6, p < 0.001). The mean angle of the scoliosis was significantly greater when the intercrest line passed through the L-5 or L4-5 disc space than when the line passed through the L-4 vertebral body (31.4° ± 7.9° vs 21.8° ± 6.7°, p = 0.01). The ODI correlated with the measurement of the angle of the scoliosis (ρ = 0.6, p < 0.001). Age, sex, osteoporosis, the direction of the scoliosis, listhesis of coronal and sagittal planes, the lateral osteophyte difference, and the vertebral body index did not correlate with curve progression. The findings of this study demonstrated that the progression of DLS was affected by the relationship between the intercrest line and the L-5 vertebra. When L-5 was deep seated, progression of DLS was found. Asymmetrical change in the disc space above and below the L-3 or apical vertebra may also be an important predictor of curve progression.

Vertebral body index and bone mineral density in women with spinal fractures. 66 probands compared with controls.

The bone mineral density (BMD) was measured in 61 women with compression fractures of the spine and 66 normal pre-menopausal women. Radiographs of the lateral spine were also obtained and the vertebral body index (VBI) was measured in the region L2-L4. Women with spinal fractures had lower BMD and VBI values. Using both BMD and VBI, 3 regions of fracture risk were defined. All but 2 of the fracture patients were in the moderate- or high-risk region for fracture.