Lumbar Facet Arthroplasty Versus Fusion for Grade-I Degenerative Spondylolisthesis with Stenosis: A Prospective Randomized Controlled Trial.

BACKGROUND: The comparative effectiveness of decompression plus lumbar facet arthroplasty versus decompression plus instrumented lumbar spinal fusion in patients with lumbar spinal stenosis and grade-I degenerative spondylolisthesis is unknown. METHODS: In this randomized, controlled, Food and Drug Administration Investigational Device Exemption trial, we assigned patients who had single-level lumbar spinal stenosis and grade-I degenerative spondylolisthesis to undergo decompression plus lumbar facet arthroplasty (arthroplasty group) or decompression plus fusion (fusion group). The primary outcome was a predetermined composite clinical success score. Secondary outcomes included the Oswestry Disability Index (ODI), visual analog scale (VAS) back and leg pain, Zurich Claudication Questionnaire (ZCQ), Short Form (SF)-12, radiographic parameters, surgical variables, and complications. RESULTS: A total of 321 adult patients were randomized in a 2:1 fashion, with 219 patients assigned to undergo facet arthroplasty and 102 patients assigned to undergo fusion. Of these, 113 patients (51.6%) in the arthroplasty group and 47 (46.1%) in the fusion group who had either reached 24 months of postoperative follow-up or were deemed early clinical failures were included in the primary outcome analysis. The arthroplasty group had a higher proportion of patients who achieved composite clinical success than did the fusion group (73.5% versus 25.5%; p < 0.001), equating to a between-group difference of 47.9% (95% confidence interval, 33.0% to 62.8%). The arthroplasty group outperformed the fusion group in most patient-reported outcome measures (including the ODI, VAS back pain, and all ZCQ component scores) at 24 months postoperatively. There were no significant differences between groups in surgical variables or complications, except that the fusion group had a higher rate of developing symptomatic adjacent segment degeneration. CONCLUSIONS: Among patients with lumbar spinal stenosis and grade-I degenerative spondylolisthesis, lumbar facet arthroplasty was associated with a higher rate of composite clinical success than fusion was at 24 months postoperatively. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Fusion's Location and Quality within the Fixated Segment Following Transforaminal Interbody Fusion (TLIF).

Transforaminal interbody fusion (TLIF) has gained increased popularity over recent decades and is being employed as an established surgical treatment for several lumbar spine pathologies, including degenerative spondylosis, spondylolisthesis, infection, tumor and some cases of recurrent disc herniation. Despite the seemingly acceptable fusion rates after TLIF (up to 94%), the literature is still limited regarding the specific location and quality of fusion inside the fixated segment. In this single-institution, retrospective population-based study, we evaluated all post-operative computed tomography (CT) of patients who underwent TLIF surgery at a medium-sized medical center between 2010 and 2020. All CT studies were performed at a minimum of 1 year following the surgery, with a median of 2 years. Each CT study was evaluated for post-operative fusion, specifically in the posterolateral and intervertebral body areas. The fusion's quality was determined and classified in each area according to Lee's criteria, as follows: (1) definitive fusion: definitive bony trabecular bridging across the graft host interface; (2) probable fusion: no definitive bony trabecular crossing but with no gap at the graft host interface; (3) possible arthrosis: no bony trabecular crossing with identifiable gap at the graft host interface; (4) definite pseudarthrosis: no traversing trabecular bone with definitive gap. A total of 48 patients were included in this study. The median age was 55.6 years (SD ± 15.4). The median time from surgery to post-operative CT was 2 years (range: 1-10). Full definitive fusion in both posterolateral and intervertebral areas was observed in 48% of patients, and 92% showed definitive fusion in at least one area (either posterolateral or intervertebral body area). When comparing the posterolateral and the intervertebral area fusion rates, a significantly higher definitive fusion rate was observed in the posterolateral area as compared to the intervertebral body area in the long term follow-up (92% vs. 52%, p < 0.001). In the multivariable analysis, accounting for several confounding factors, including the number of fixated segments and cage size, the results remained statistically significant (p = 0.048). In conclusion, a significantly higher definitive fusion rate at the posterolateral area compared to the intervertebral body area following TLIF surgery was found. Surgeons are encouraged to employ bone augmentation material in the posterolateral area (as the primary site of fusion) when performing TLIF surgery.

Scoliosis in osteogenesis imperfecta: results of posterior spinal fusion in 39 patients.

PURPOSE: To evaluate the outcomes of scoliosis corrective surgery in Osteogenesis Imperfecta (OI) patients with primarily pedicles screw fixation in terms of correcting and maintaining the correction of the spinal deformity, and to assess for several peri-operative parameters and complications associated with this surgical treatment. METHODS: Retrospective case series of 39 consecutive patients with OI treated surgically for scoliosis. The surgeries were performed between 2002 and 2020 by three different surgeons. All patients' medical peri-operative and post-operative charts were evaluated. Radiological assessment was performed by evaluation of the pre-operative, immediate post-operative and last follow-up plain radiographs. RESULTS: There were 20 females and 19 males included in this review with a mean age of 14 years (range, 6-20 years) at the time of surgery. The median follow-up time was 7.9 years. The mean pre-operative cobb angle (CA) of the major curve was 76.5 degrees (SD ± 18.9), decreasing to 42.6 (SD ± 17.4) in the long-term post-operative follow-up (P < 0.001). A total of 21 adverse events in 16 patients were noted. Only 4 patients required subsequent invasive surgical treatment or prolonged hospital stay. All other patients were treated conservatively with no lasting complication. CONCLUSION: Scoliosis surgical correction in OI patients seems to yield acceptable results, with maintained coronal plane surgical correction in the long-term follow-up. Even though a high peri-operative complications rate is observed in this series, there were no long-term sequelae or lasting complications. LEVEL OF EVIDENCE: Level IV, Case series.

Traumatic Posterior Atlantoaxial Dislocation With an Associated Fracture: A Systematic Review.

STUDY DESIGN: Systematic review. OBJECTIVE: To investigate the clinical presentation, mechanism of injury, patients' characteristics, diagnosis, treatment, and prognosis of traumatic posterior atlantoaxial dislocation with fracture (TPAD). BACKGROUND: TPAD is an extremely rare entity, with a limited number of cases reported in the literature. Although rare, a thorough understanding of the pathogenesis and management of such cases is required due to the high risk of spinal cord compression and the severity of neurological deficits. We conducted a systematic review of all cases of TPAD with fractures reported in the literature. METHODS: This systematic review was conducted following the Preferred Reporting Items for Systematic reviews and Meta-analysis guidelines. Relevant literature was retrieved from the Pubmed database. All published English-written studies involving human subjects with relevant data regarding TPAD were included. RESULTS: Two case series and 20 case reports published between 1924 and 2021 describing 28 patients with TPAD were included. The median age at presentation was 51.5 years, with male predominance (83%). The most common fracture pattern was Anderson and D'alonzo type II odontoid fracture (78%). Neurological exam at presentation was intact in 52% of patients. The primary diagnostic imaging was computed tomography employed in 96% of cases. The management consisted of 2 stages protocol, initially, a temporary axial traction was employed (54%), and later definitive surgical treatment was employed (93%). The posterior surgical approach was favored in 82% of cases. CONCLUSION: TPAD with fracture occurred in the majority of cases with Anderson and D'alonzo type II odontoid fracture, predominantly in males. Diagnosis is usually established based on computed tomography imaging; further imaging may not be indicated as it does not seem to alternate the patient's management course. Surgical intervention was employed in almost all cases, with favored results through posterior C1-C2 fusion. LEVEL OF EVIDENCE: Level-IV.

A Prospective Study of Lumbar Facet Arthroplasty in the Treatment of Degenerative Spondylolisthesis and Stenosis: Results from the Total Posterior Spine System (TOPS) IDE Study.

STUDY DESIGN: Prospective randomized Food and Drug Administration investigational device exemption clinical trial. OBJECTIVE: The purpose of the present study is to report the 1-year clinical and radiographic outcomes and safety profile of patients who underwent lumbar facet arthroplasty through implantation of the Total Posterior Spine System (TOPS) device. SUMMARY OF BACKGROUND DATA: Lumbar facet arthroplasty is one proposed method of dynamic stabilization to treat grade-1 spondylolisthesis with stenosis; however, there are currently no Food and Drug Administration-approved devices for facet arthroplasty. METHODS: Standard demographic information was collected for each patient. Radiographic parameters and patient-reported outcome measures were assessed preoperatively and at regular postoperative intervals. Complication and reoperation data were also collected for each patient. RESULTS: At the time of this study, 153 patients had undergone implantation of the TOPS device. The mean surgical time was 187.8 minutes and the mean estimated blood loss was 205.7cc. The mean length of hospital stay was 3.0 days. Mean Oswestry Disability Index, Visual Analog Score leg and back, and Zurich Claudication Questionnaire scores improved significantly at all postoperative time points ( P >0.001). There were no clinically significant changes in radiographic parameters, and all operative segments remained mobile at 1-year follow-up. Postoperative complications occurred in 11 patients out of the 153 patients (7.2%) who underwent implantation of the TOPS device. Nine patients (5.9%) underwent a total of 13 reoperations, 1 (0.6%) of which was for device-related failure owing to bilateral L5 pedicle screw loosening. CONCLUSIONS: Lumbar facet arthroplasty with the TOPS device demonstrated a statistically significant improvement in all patient-reported outcome measures and the ability to maintain motion at the index level while limiting sagittal translation with a low complication rate.

Prospective, randomized controlled multicenter study of posterior lumbar facet arthroplasty for the treatment of spondylolisthesis.

OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of a posterior facet replacement device, the Total Posterior Spine (TOPS) System, for the treatment of one-level symptomatic lumbar stenosis with grade I degenerative spondylolisthesis. Posterior lumbar arthroplasty with facet replacement is a motion-preserving alternative to lumbar decompression and fusion. The authors report the preliminary results from the TOPS FDA investigational device exemption (IDE) trial. METHODS: The study was a prospective, randomized controlled FDA IDE trial comparing the investigational TOPS device with transforaminal lumbar interbody fusion (TLIF) and pedicle screw fixation. The minimum follow-up duration was 24 months. Validated patient-reported outcome measures included the Oswestry Disability Index (ODI) and visual analog scale (VAS) for back and leg pain. The primary outcome was a composite measure of clinical success: 1) no reoperations, 2) no device breakage, 3) ODI reduction of ≥ 15 points, and 4) no new or worsening neurological deficit. Patients were considered a clinical success only if they met all four measures. Radiographic assessments were made by an independent core laboratory. RESULTS: A total of 249 patients were evaluated (n = 170 in the TOPS group and n = 79 in the TLIF group). There were no statistically significant differences between implanted levels (L4-5: TOPS, 95% and TLIF, 95%) or blood loss. The overall composite measure for clinical success was statistically significantly higher in the TOPS group (85%) compared with the TLIF group (64%) (p = 0.0138). The percentage of patients reporting a minimum 15-point improvement in ODI showed a statistically significant difference (p = 0.037) favoring TOPS (93%) over TLIF (81%). There was no statistically significant difference between groups in the percentage of patients reporting a minimum 20-point improvement on VAS back pain (TOPS, 87%; TLIF, 64%) and leg pain (TOPS, 90%; TLIF, 88%) scores. The rate of surgical reintervention for facet replacement in the TOPS group (5.9%) was lower than the TLIF group (8.8%). The TOPS cohort demonstrated maintenance of flexion/extension range of motion from preoperatively (3.85°) to 24 months (3.86°). CONCLUSIONS: This study demonstrates that posterior lumbar decompression and dynamic stabilization with the TOPS device is safe and efficacious in the treatment of lumbar stenosis with degenerative spondylolisthesis. Additionally, decompression and dynamic stabilization with the TOPS device maintains segmental motion.

Radiographic Bone Healing in Minimally Invasive Floating Metatarsal Osteotomy for Neuropathic Plantar Metatarsal Head Ulcers - A Retrospective Cohort Study.

Minimally invasive floating metatarsal osteotomy is an option for treating neuropathic ulcers under the metatarsal heads. This study presents the radiographic results of the floating metatarsal osteotomy. We reviewed files and radiographs at least 4 months after a floating metatarsal osteotomy in patients with diabetic neuropathy. In 71 osteotomies in 54 patients with late onset diabetes (mean age 61 ± 9, mean HbA1c 7.9 ± 1.9%), the primary ulcer healed within 3.5 ± 1.4 weeks. Of 66 osteotomies where radiographs were available 10 had non-union (15%, all asymptomatic), 15 (23%) had hypertrophic callus formation and 41 (62%) had normal union. One patient developed an ulcer under the hypertrophic callus. This necessitated callus resection. Asymptomatic non-union may happen in 15% of floating osteotomies, but the osteotomies appear to be relatively safe and effective for neuropathic plantar metatarsal head ulcers. Hypertropic callus causing local re-ulceration is rare and can be managed surgically.

The XVS System During Open Spinal Fixation Procedures in Patients Requiring Pedicle Screw Placement in the Lumbosacral Spine.

OBJECTIVE: This pilot study was undertaken to evaluate the safety, performance, and usability of the Xvision-Spine (XVS) System (Augmedics, Arlington Heights, IL) during open spinal fixation procedures in patients requiring pedicle screw placement in the lumbosacral spine. METHODS: The XVS System is an augmented reality head-mounted display (HMD) based on a computer navigation system designed to assist surgeons in accurately placing pedicle screws. It uses an HMD-mounted tracking camera to provide optical tracking technology, and provides the surgeon a translucent direct near-eye display of the navigated surgical instrument's location relative to the computed tomographic image. We report the preliminary results of a prospective series of all consecutive patients who underwent augmented reality-assisted pedicle screw placement in the lumbosacral vertebrae at 3 institutions. Clinical accuracy for each pedicle screw was graded with Gertzbein-Robbins scores by 2 independent and blinded neuroradiologists. RESULTS: The 19 study participants included 8 men and 11 women with a mean age of 59.13 ± 12.09 and 59.91 ± 12.89 years, respectively. Seventeen procedures were successfully completed via the XVS System. Two procedures were not completed due to technical issues with the system's intraoperative scanner. A total of 86 screws were inserted. The accuracy of the XVS System was 97.7%. CONCLUSIONS: The XVS System's performance in accurate placement of pedicle screws in the lumbosacral vertebrae had an overall accuracy of 97.7%. These preliminary results were comparable to the accuracy of other manual computer-assisted navigation systems reported in the literature.

Kyphoplasty for Elderly Patients With Vertebral Compression Fractures-Do We Save Lives? Mortality Rates Analysis Comparison in a Long-Term Follow-Up Cohort.

STUDY DESIGN: Retrospective cohort. OBJECTIVES: We aimed to compare a large cohort of patients with vertebral compression fractures (VCF) treated in 2 centers using different protocols (conservative vs BKP) and compare mortality rates on a long-term follow-up. METHODS: Retrospective cohort held in 2 medical centers (W and AH). All patients admitted with VCF from November 2008 to January 2015 were enrolled in the study. Exclusion criteria were patients admitted with non-osteoporotic pathological fractures (such as metastatic or MM). RESULTS: Our study included 208 patients treated for VCF, 127 were treated with BKP (88 females, 69.3%) and 81 were treated conservatively (59 females, 72.8%). Patients from Centre W were older and frailer compared to the patients from AH center (Average age 75.12 ± 11.16 vs 69.13 ± 9.61 years and Frailty score of 0.16 ± 0.1 vs 0.12 ± 0.1 respectively, T-test, p < 0.01 for both). Hazard ratios (HR) for age, female gender and frailty were significant for increased mortality, frailty had the highest HR of 182.42 (CI 29.05-1145.33, p < 0.01). Multivariate Cox model was fitted and after accounting for Gender, Age and Frailty, no significant difference was found between the 2 medical centers mortality rates (p = 0.59), thus no difference in mortality rates between BKP and conservative treatment in our study. CONCLUSION: long-term follow-up following BKP treatment for VCF did not show a reduced mortality rate compared to conservative treatment after accounting for frailty, age and gender. Frailty was the most important factor in predicting mortality. Further RCTs are needed to compare the quality of life differences between the 2 treatment strategies.

Height Gain Prediction in Adolescent Idiopathic Scoliosis Based on Preoperative Parameters.

BACKGROUND: The purpose of the study was to identify preoperative parameters which are associated with height gain after corrective surgery for adolescent idiopathic scoliosis (AIS) and their use to preoperatively quantify the potential for height gain after AIS correction. METHODS: Our study included 87 consecutive patients with AIS who underwent posterior fusion. Patients' height was measured the day before surgery and before their discharge. Demographic and radiologic variables were analyzed for predictability of height gain. RESULTS: The mean height gain was 3.85 cm. We have found a statistically significant correlation between height gain and the following measures: preoperative thoracic curve, preoperative thoracolumbar curve, preoperative thoracic kyphosis, flexibility of the main thoracic and thoracolumbar curves, and number of fused levels (all P<0.05). Patients with Lenke type 1 and 2 had statistically less height gain compared with patients with Lenke type 3, 4, 6. CONCLUSION: Most of the scoliosis patients with Lenke type 1 and 2 will gain up to 3 cm after surgery while most of the patients with Lenke type 3, 4, 6 will gain more than 3 cm. Most patients with Lenke type 3, 4, 6 with a major curve of less than 60 degrees will gain up to 4 cm, while most of those with a major curve of more than 60 degrees will gain more than 4 cm. Patient with a positive thoracic sagittal modifier tend to have more height gain after surgery.

Gas forming infection of the spine: a systematic and narrative review.

PURPOSE: Gas forming infection (GFI) of the spine is a rapidly progressive and potentially life-threatening infection. It can be a consequence of aetiologies such as Emphysematous Osteomyelitis (EOM), Necrotizing Fasciitis (NF), and Gas-containing Spinal Epidural Abscess (Gas-containing SEA). This review aims to summarize the characteristics of these subtypes of GFI, describing their aetiology, diagnosis, management, and prognosis. METHODS: PubMed, Embase, Web of Science and the Cochrane Database were systematically searched for studies reporting on gas forming infections of the spine or a known subtype. Cases of post-operative and iatrogenic spinal infection were excluded. RESULTS: The literature review revealed 35 studies reporting on 28 cases of EOM, three cases of NF involving the spine and seven cases of Gas-containing SEA. Thirty studies reporting on 32 cases of GFI were available for data analysis. The mean age of the patients was 60.9 years and a concomitant diagnosis of diabetes mellitus was reported in 57.5% of patients infected. Fever and back pain were the most common presenting symptoms. The lumbar spine was the most commonly affected spinal segment. Mortality from EOM, NF and Gas-containing SEA were 34.8, 100 and 28.5%, respectively. DISCUSSION: Gas forming infection of the spine is a rare condition with an extremely poor prognosis, requiring early and aggressive surgical treatment. A multi-disciplinary approach is necessary for management. Nonetheless, even in cases of early recognition and optimal management, multisystem failure may still occur, and mortality rates remain high due to the aggressive nature of this infection. LEVEL OF EVIDENCE: Systematic review of level IV studies.

Routine sagittal whole-spine magnetic resonance imaging in finding incidental spine lesions.

PURPOSE: To examine the efficacy and feasibility of T2-weighted whole-spine sagittal magnetic resonance imaging (MRI) screening for all patients who undergo MRI of the lumbar spine for any indication. METHODS: A review of 1145 consecutive T2-weighted whole-spine sagittal MRI screening sequences performed for lumbar spine imaging was undertaken for the purposes of documenting the incidence and clinical significance of thoracic and cervical spine incidental findings, as well as to establish correlation between these pathologies and those found in the lumbar spine. RESULTS: Out of the 1145 patients included in the study, 103 (9%) patients had incidental findings thought to be significant. These findings included cervical spinal stenosis (n = 85), thoracic disc herniation (n = 9), syrinx (n = 5), intradural tumor (n = 2), and signal changes within the spinal cord (n = 2). In follow-up exams, 35 patients had clinically significant findings which included cervical myelopathy (n = 25), thoracic myelopathy (n = 3), syrinx (n = 5) and intradural tumor (n = 2). Among the 172 patients presenting with lumbar spinal stenosis, 42 (24.4%) had such incidental findings, and of those 41 (23.8%) had cervical stenosis with spinal cord compression (p < 0.0001). CONCLUSION: T2-weighted whole-spine sagittal screening is useful in demonstrating clinically relevant incidental findings in any patients undergoing MRI of the lumbar spine. There is a statistically significant correlation between lumbar spinal stenosis and cervical spinal stenosis with spinal cord compression.

Long-term results for total lumbar facet joint replacement in the management of lumbar degenerative spondylolisthesis.

OBJECTIVE: The authors evaluated the long-term clinical outcome of a total posterior arthroplasty system in the surgical treatment of lumbar spinal stenosis with degenerative spondylolisthesis. METHODS: Between June 2006 and July 2007, 10 patients with neurogenic claudication due to spinal stenosis and single-level degenerative spondylolisthesis were enrolled in a nonrandomized prospective clinical study. The patients were evaluated with radiographs and MRI scans, the visual analog scale (VAS) for back and leg pain, the Oswestry Disability Index (ODI), and the SF-36 health survey preoperatively and at 6 weeks, 3 months, 6 months, 1 year, 2 years, 3 years, 7 years, and 11 years postoperatively. RESULTS: The mean VAS score for leg pain dropped from 83.5 before surgery to 13 at 6 weeks and 17 at 11 years after surgery. The mean VAS score for back pain dropped from 56.2 preoperatively to 12.5 at 6 weeks and 14 at 11 years after surgery. The mean ODI score decreased from 49.1 preoperatively to 13.5 at 6 weeks and 16 at 11 years after surgery. MRI at 11 years demonstrated stenosis adjacent to the stabilized segment in one patient. This patient was not symptomatic. The authors did not find evidence of progression of the spondylolisthesis in any of the cases. In one patient, conversion to posterolateral fusion was performed due to an early device malfunction. CONCLUSIONS: The results of this 11-year follow-up study demonstrate that, in patients with spinal stenosis and degenerative spondylolisthesis, decompression and posterior arthroplasty maintain clinical improvement and radiological stability.

The Proprioceptive System Masterminds Spinal Alignment: Insight into the Mechanism of Scoliosis.

Maintaining posture requires tight regulation of the position and orientation of numerous spinal components. Yet, surprisingly little is known about this regulatory mechanism, whose failure may result in spinal deformity as in adolescent idiopathic scoliosis. Here, we use genetic mouse models to demonstrate the involvement of proprioception in regulating spine alignment. Null mutants for Runx3 transcription factor, which lack TrkC neurons connecting between proprioceptive mechanoreceptors and spinal cord, developed peripubertal scoliosis not preceded by vertebral dysplasia or muscle asymmetry. Deletion of Runx3 in the peripheral nervous system or specifically in peripheral sensory neurons, or of enhancer elements driving Runx3 expression in proprioceptive neurons, induced a similar phenotype. Egr3 knockout mice, lacking muscle spindles, but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types may be required for this regulatory mechanism. These findings uncover a central role for the proprioceptive system in maintaining spinal alignment.

Seven years follow-up for total lumbar facet joint replacement (TOPS) in the management of lumbar spinal stenosis and degenerative spondylolisthesis.

PURPOSE: To evaluate the feasibility and clinical improvement of a total posterior arthroplasty system in the surgical management of lumbar degenerative spondylolisthesis and or spinal stenosis. METHODS: During a 1-year period (June 2006 to July 2007), ten patients were enrolled in a non-randomized prospective clinical study. The primary indication was neurogenic claudication due to spinal stenosis with single-level degenerative spondylolisthesis. Patients were evaluated with X-rays and MRI scans, visual analog scale (VAS) for back and leg pain, the Oswestry disability questionnaire, and the SF-36 health survey preoperatively, at 6 weeks, 3 months and 6 months and at 1, 2, 3 and 7 years postoperatively. RESULTS: The VAS score for back pain dropped from 56.2 preoperatively to 12.5 at 6 weeks and 19 at 7 years follow-up. The VAS score for worse leg pain dropped from 83.5 before surgery to 13 at 6 weeks and 8.8 at 7 years follow-up. The ODI dropped from 49.1 preoperatively to 13.5 at 6 weeks and 7.8 at 7 years follow-up. MRI examination at 7 years after surgery did not demonstrate stenosis adjacent to the stabilized segment. Spondylolisthesis did not progress in any of the cases. One patient had a symptomatic L3-L4 far lateral disc herniation 5 years after surgery whose symptoms resolved with non-operative treatment. In one patient, conversion to posterolateral fusion was performed due to an early device malfunction. CONCLUSION: In patients with spinal stenosis and degenerative spondylolisthesis, decompression and posterior arthroplasty with the TOPS System can maintain clinical improvement and radiologic stability over time.

Surgical management of moderate adolescent idiopathic scoliosis with ApiFix®: a short peri- apical fixation followed by post-operative curve reduction with exercises.

Surgery in adolescent idiopathic scoliosis (AIS) is a major operative intervention where 10-12 vertebrae are instrumented and fused. A smaller motion preserving surgery would be more desirable for these otherwise healthy adolescents. The ApiFix® system is a novel less invasive short segment pedicle screw based instrumentation inserted around the apex of the main curve. The system has a ratchet mechanism that enables gradual postoperative device elongation and curve correction. The ratchet is activated by performing specific spinal exercises. The unique features of the device allow curve correction without fusion. The system which has a CE approval was employed in adolescents with main thoracic curves. More than a dozen of ApiFix surgeries have been performed so far. The preoperative Cobb angle was 45° ± 8, and 25° ± 8 at final follow up. The following is a report on three adolescent females aged 13-16 years with curves between 43°-53° and Risser sign of 1-4 who underwent surgery with ApiFix®. Two pedicle screws were inserted around the curve apex and the ratchet based device with polyaxial ring connectors was attached to the screws. No fusion attempt was made. Operative time was around one hour. Two weeks after surgery the patients were instructed to perform Schroth like daily exercises with the aim of rod elongation and gradual curve correction. Patients were followed between 6 months to 2 years. Curves were reduced and maintained between 22- 33°. Patients were pain free and were able to perform their spinal exercises. Postoperative gradual elongation of the device was observed. No screw loosening or rod breakage were observed. No adding on or curve progression was seen. Three factors may contribute to the ApiFix® success: polyaxial connections that prevent mechanical failure, gradual curve correction by spinal motion and spinal growth modulation. The ApiFix® system allows managing moderate AIS with a simple and minor surgical intervention. Recovery is rapid with negligible motion loss. It allows gradual and safe curve correction with high patient satisfaction. It may also serve as an internal brace for AIS.

The relation between location of cervical cord compression and the location of myelomalacia.

OBJECTIVE: The purpose of this study was to examine the relationship between the location of the cervical cord compression and the increased signal intensity within the cervical cord on T2-weighted imaging (T2WI) in patients with cervical myelopathy and myelomalacia. MATERIALS AND METHODS: We reviewed 1,615 MRI reports from January 2011 to May 2013 from a single institution. Of the 1,615 reports reviewed, 168 patients were diagnosed with increased signal intensity within the cervical spine on T2WI. After applying the exclusion criteria 82 patients were included in the study. The MRIs of these 82 patients were then reviewed and the location of the increased signal intensity on T2WI in relation to the location of the pressure on the spinal cord was recorded. RESULTS: In more than 50 % of the cases the lesions with increased signal intensity on T2WI either were located distal to the pressure on the spinal cord or started at the level of the pressure and extended to an area distal to the pressure. In 26 out of the 92 lesions with increased signal intensity on T2WI, the lesion started proximal to the pressure on the spinal cord and extended distal to it. In only 3 out of the 92 lesions, the lesion with increased signal intensity on T2WI was solely located proximal to the pressure on the spinal cord. In 5 other cases the lesion with increased signal intensity on T2WI started proximal to the level of pressure on the spinal cord and extended into the level of pressure on the spinal cord (p < 0.001; Table 1). CONCLUSION: Cervical myelomalacia may appear proximal, distal or at the level of the compressed cord. It rarely appears solely proximal to the pressure area on the cord.

Incidental dural tears during lumbar spine surgery: a retrospective case study of 84 degenerative lumbar spine patients.

STUDY DESIGN: A retrospective case study. PURPOSE: To retrospectively review all incidental dural tears (DTs) that occurred at a single institution, classify them anatomically and evaluate the clinical significance of each subgroup. OVERVIEW OF LITERATURE: Dural tears are considered the most commonly encountered complication during lumbar spine surgery. In contrast to the high frequency of DTs, reports on the characteristic location and mechanism are sparse. METHODS: We retrospectively retrieved all cases of degenerative lumbar spine surgery performed over a 9-year period and classified all identified DTs according to two independent planes. The coronal plane was divided into lower, middle and upper surgical fields, and the sagittal plane into posterior, lateral and ventral occurring tears. Demographic and clinical variables were retrieved and analyzed to search for significant associations. RESULTS: From 2003 to 2011, 1,235 cases of degenerative lumbar spine conditions were treated surgically at our institution. In 84 operations (6.8%), an incidental DT was either identified intraoperatively or suspected retrospectively. The most commonly involved location was the lower surgical field (n=39, 46.4%; p=0.002), followed equally by the middle and upper fields (n=16, 19%). In the sagittal plane, the most commonly involved locations were those in close proximity to the nerve root (n=35, 41.6%), followed by the dorsal aspect of the dural sac (n=24, 28.6%). None of the variables recorded was found to be associated with a particular location. CONCLUSIONS: In our series, incidental DTs were found to occur most commonly in the lower surgical field. We hypothesize that local anatomic feature, such as the lordotic and broadening lumbar dura, may play a role in the observed DT tendency to occur in the lower surgical field. In light of the high frequency and potentially substantial resulting morbidity of incidental DTs, a better characterization of its location and mechanism may optimize both prevention and management.

Predictors of back pain in adolescent idiopathic scoliosis surgical candidates.

BACKGROUND: There are contradictory reports on the overall prevalence of back pain in the adolescent population compared with adolescent idiopathic scoliosis (AIS) patients. Most reports do not investigate pain in patients with AIS but try to identify in which subgroup of patients with AIS an underlying pathology should be excluded. The objective of this study was to find whether AIS in operative candidate patients is a painful condition and to try and find clinical and radiologic predisposing factors, which will help us to predict patients who are going to have pain. METHODS: Candidates who had to undergo an operative treatment for AIS between October 2004 and October 2009 in our institution, were enrolled to the study. Pain was graded with the use of visual analogue scale (VAS) on a scale from 0 to 10. We recorded the age at presentation, sex, menarchal status, family history of scoliosis, brace treatment history, and neurological findings. Radiologic parameters recorded were: the type of curve according to the Lenke classification, Cobb angle, thoracic kyphosis angle, apex vertebra rotation, Risser grade, coronal balance, and curves flexibility. RESULTS: Seventy patients with AIS were included in this study. Fifty patients (71%) reported of some kind of back pain with 34 patients (48%) grading their pain as ≥5 on the VAS.Patients in whom scoliosis was diagnosed in older age and patients with a more rigid lumbar curve had statistically significant higher VAS scores (P=0.014, P=0.036). Patients who were treated with a brace had a statistically significant lower VAS scores (P=0.019). CONCLUSIONS: Back pain is common in patients with AIS who are candidates for operative treatment. The following parameters correlate with worse back pain: older age at diagnosis, no use of brace, and rigid lumbar curve. LEVEL OF EVIDENCE: Type III.