Incidence and risk factors of proximal junctional kyphosis in adolescent idiopathic scoliosis after correction surgery: a meta-analysis and systematic review.

AIM: To analyze the risk factors of proximal junctional kyphosis (PJK) after correction surgery in patients with adolescent idiopathic scoliosis (AIS). METHODS: PubMed, Medline, Embase, Cochrane Library, Web of Science, CNKI, and EMCC databases were searched for retrospective studies utilizing all AIS patients with PJK after corrective surgery to collect preoperative, postoperative, and follow-up imaging parameters, including thoracic kyphosis (TK), lumbar lordosis (LL), proximal junctional angle (PJA), the sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), pelvic incidence-lumbar lordosis (PI-LL), sacral slope (SS), rod contour angle (RCA) and upper instrumented vertebra (UIV). RESULTS: Nineteen retrospective studies were included in this meta-analysis, including 550 patients in the intervention group and 3456 patients in the control group. Overall, sex (OR 1.40, 95% CI (1.08, 1.83), P = 0.01), larger preoperative TK (WMD 6.82, 95% CI (5.48, 8.16), P < 0.00001), larger follow-up TK (WMD 8.96, 95% CI (5.62, 12.30), P < 0.00001), larger postoperative LL (WMD 2.31, 95% CI (0.91, 3.71), P = 0.001), larger follow-up LL (WMD 2.51, 95% CI (1.19, 3.84), P = 0.0002), great change in LL (WMD - 2.72, 95% CI (- 4.69, - 0.76), P = 0.006), larger postoperative PJA (WMD 4.94, 95% CI (3.62, 6.26), P < 0.00001), larger follow-up PJA (WMD 13.39, 95% CI (11.09, 15.69), P < 0.00001), larger postoperative PI-LL (WMD - 9.57, 95% CI (- 17.42, - 1.71), P = 0.02), larger follow-up PI-LL (WMD - 12.62, 95% CI (- 17.62, - 7.62), P < 0.00001), larger preoperative SVA (WMD 0.73, 95% CI (0.26, 1.19), P = 0.002), larger preoperative SS (WMD - 3.43, 95% CI (- 4.71, - 2.14), P < 0.00001), RCA (WMD 1.66, 95% CI (0.48, 2.84), P = 0.006) were identified as risk factors for PJK in patients with AIS. For patients with Lenke 5 AIS, larger preoperative TK (WMD 7.85, 95% CI (5.69, 10.00), P < 0.00001), larger postoperative TK (WMD 9.66, 95% CI (1.06, 18.26), P = 0.03, larger follow-up TK (WMD 11.92, 95% CI (6.99, 16.86), P < 0.00001, larger preoperative PJA (WMD 0.72, 95% CI (0.03, 1.41), P = 0.04, larger postoperative PJA (WMD 5.54, 95% CI (3.57, 7.52), P < 0.00001), larger follow-up PJA (WMD 12.42, 95% CI 9.24, 15.60), P < 0.00001, larger follow-up SVA (WMD 0.07, 95% CI (- 0.46, 0.60), P = 0.04), larger preoperative PT (WMD - 3.04, 95% CI (- 5.27, - 0.81), P = 0.008, larger follow-up PT (WMD - 3.69, 95% CI (- 6.66, - 0.72), P = 0.02) were identified as risk factors for PJK. CONCLUSION: Following corrective surgery, 19% of AIS patients experienced PJK, with Lenke 5 contributing to 25%. Prior and post-op measurements play significant roles in predicting PJK occurrence; thus, meticulous, personalized preoperative planning is crucial. This includes considering individualized treatments based on the Lenke classification as our future evaluation standard.

Comparison of instrumented and stand-alone lateral lumbar interbody fusion for lumbar degenerative disease: a systematic review and meta-analysis.

BACKGROUND: Both instrumented and stand-alone lateral lumbar interbody fusion (LLIF) have been widely used to treat lumbar degenerative disease. However, it remains controversial as whether posterior internal fixation is required when LLIF is performed. This meta-analysis aims to compare the radiographic and clinical results between instrumented and stand-alone LLIF. METHODS: PubMed, EMBASE and Cochrane Collaboration Library up to March 2023 were searched for studies that compared instrumented and stand-alone LLIF in the treatment of lumbar degenerative disease. The following outcomes were extracted for comparison: interbody fusion rate, cage subsidence rate, reoperation rate, restoration of disc height, segmental lordosis, lumbar lordosis, visual analog scale (VAS) scores of low-back and leg pain and Oswestry Disability Index (ODI) scores. RESULTS: 13 studies involving 1063 patients were included. The pooled results showed that instrumented LLIF had higher fusion rate (OR 2.09; 95% CI 1.16-3.75; P = 0.01), lower cage subsidence (OR 0.50; 95% CI 0.37-0.68; P < 0.001) and reoperation rate (OR 0.28; 95% CI 0.10-0.79; P = 0.02), and more restoration of disc height (MD 0.85; 95% CI 0.18-1.53; P = 0.01) than stand-alone LLIF. The ODI and VAS scores were similar between instrumented and stand-alone LLIF at the last follow-up. CONCLUSIONS: Based on this meta-analysis, instrumented LLIF is associated with higher rate of fusion, lower rate of cage subsidence and reoperation, and more restoration of disc height than stand-alone LLIF. For patients with high risk factors of cage subsidence, instrumented LLIF should be applied to reduce postoperative complications.

Effect of long-term cervical extensor exercise program on functional disability, pain intensity, range of motion, cervical muscle mass, and cervical curvature in young adult population with chronic non-specific neck pain: a randomized controlled trial.

BACKGROUND: The prevalence of chronic non-specific neck pain (CNNP) is on the rise among the young adult population. We herein aimed to compare the effects of long-term specific cervical extensor training and stretching exercises on improving this chronic disorder in young adults. METHODS: In this prospective, randomized, controlled study, 70 participants aged 18-35 years with CNNP and cervical lordosis loss were included. The participants were assigned to undergo either specific cervical extensor training (observation group) or perform usual stretching exercises (control group). The exercise duration was set at 12 months, with 9 months at the clinic and 3 months at home. The outcome assessments included changes in the neck disability index, visual analog scale from baseline, cervical range of motion (CROM), cross-sectional areas (CSAs) of cervical extensors, and cervical curvature from baseline. The outcome measures were compared between groups at 3, 6, and 12 months of follow-up. RESULTS: All 70 participants underwent randomization, and no significant differences in demographics and baseline data were found between the two groups. The observation group showed a greater improvement in neck disability index and visual analog scale scores at the 12-month follow-up than the control group. Additionally, a more substantial increase in CROM and CSAs of cervical extensors was observed in the observation group at the 6-month and 12-month follow-ups (P < 0.05). Although more participants in the observation group achieved cervical lordosis at the 12-month follow-up, the difference was marginally nonsignificant (9% in the control group vs. 28% in the observation group, P = 0.075). CONCLUSIONS: In young adults with CNNP, long-term specific cervical extensor training was associated with a more significant clinically meaningful improvement in disability, pain, and CROM than stretching exercises. The increased CSAs of cervical extensors may potentially contribute to the restoration of cervical lordosis. Trial registration The study is registered at the Chinese domestic clinical trial (ChiCTR2000040009) at Chictr.org. The date of registration: November 18, 2020.

Clinical outcome of percutaneous endoscopic lumbar decompression in treatment of elderly patients with lumbar spinal stenosis: a matched retrospective study.

PURPOSE: This retrospective cohort study aimed to evaluate the efficacy and safety of percutaneous endoscopic lumbar decompression (PELD) in elderly patients with lumbar spinal stenosis (LSS). STUDY DESIGN: A matched retrospective study. SETTING: The research was conducted in Beijing Chaoyang Hospital, Capital Medical University, China. METHODS: This study included patients treated with PELD for LSS from September 2016 to September 2020. Patients with LSS aged ≥ 80 years were screened according to the inclusion and exclusion criteria as the study group, and then the same number of patients with LSS aged 50-80 years were matched according to gender, stenosis type, and surgical segment as the control group. Preoperative patient status was assessed using the Charlson comorbidity index (CCI) and the American Society of Anesthesiologists (ASA) physical status classification score. Clinical outcomes were assessed using the visual analog scale (VAS), Oswestry Disability Index (ODI) scores, modified Macnab criteria, radiological parameters and complication rates. RESULTS: A total of 624 LSS patients met the screening criteria between September 2016 and September 2020, with 47 LSS patients ≥ 80 years old serving as the study group. Forty-seven LSS patients aged 50-80 years were matched to the study group according to gender, stenosis type, and stenosis segment. The CCI score (1.77 ± 1.67) and ASA classification (2.62 ± 0.74) of the study group were significantly higher than the CCI score (0.66 ± 0.96) and ASA classification (1.28 ± 0.54) of the control group, and the difference was statistically significant. Compared with preoperative data, postoperative ODI, leg pain VAS scores and back pain VAS scores were significantly improved in both groups (p < 0.05). However, no significant difference was found between two groups in preoperative and postoperative ODI, leg pain VAS scores and back pain VAS scores (p > 0.05). The operation time and postoperative hospital stay in control group were significantly lower than those in study (p < 0.05), but there was no significant difference in blood loss between the two groups (p > 0.05). Besides, overall radiological parameters were comparable in elder and younger patients (p > 0.05), and disc height (DH), lumbar lordosis and segmental lordosis decreased after two year follow-up in both groups (p < 0.05). In addition, complication rates were similar between the two groups (p > 0.05), and no serious complications and deaths were found. LIMITATIONS: Single-centre retrospective design, non-randomized sample, small sample size. CONCLUSION: Although elderly LSS patients (≥ 80 years old) are less fit and have more comorbidities, satisfactory outcomes can be achieved with PELD, comparable to those of LSS patients < 80 years old, and without increased complications.

Changes in Spinopelvic Parameters Between Standing and Sitting Postures: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To report the ratio-of-differences between standing and sitting. To understand how sex and age influence these differences. SUMMARY OF BACKGROUND DATA: Currently, spinal deformity surgery aims to realign the sagittal profile of the spine with-reference-to the standing posture resulting in overcorrection. New studies report significant disparities between standing and sitting spinal alignment. METHODS: A comprehensive search and review of the published literature was performed on 4 platforms in accordance with the PRISMA 2009 checklist by 2 authors independently. RESULTS: From 753 abstracts extracted from the databases, 38 papers involving 5423 patients were identified. sagittal vertical axis was more positive in sitting, with a pooled mean difference of 29.5 mm (95% CI: 17.9-41.0). Pelvic tilt (PT) was larger in sitting, with a pooled mean difference of 16.7 degrees (95% CI: 12.5-20.9), and a pooled odds ratio of 1.2(95% CI:1.1-1.3. P =0.001). Sacral Slope (SS) was smaller and lumbar lordosis (LL) was less lordotic in sitting, with a pooled mean difference of 15.0 degrees (95% CI: 11.918.1) and 21.1 degrees (95% CI:14.5-27.8), respectively, and a pooled odds ratio of 0.7 (95% CI: 0.6-0.8. P <0.001) and 0.7 (95% CI:0.6-0.7, P <0.001), respectively. Pelvic incidence and thoracic kyphosis was similar in sitting. Subgroup meta-analysis comparing odd ratio of standing to sitting showed: Among younger patients (age younger than 50), the PT and LL pooled odds-ratios were 1.4 and 0.7, respectively. Among older patients (age older than or equal to 50), the PT and LL pooled odds-ratios were 1.1 and 0.8, respectively. Among female patients, the SS pooled odds ratio was 0.6. Among male patients, the SS pooled odds ratio was 0.7. CONCLUSION: When comparing sitting to standing, it gives a more positive sagittal vertical axis, a smaller SS and LL, and a larger PT. pelvic incidence and thoracic kyphosis remained similar. Younger and female patients have pronounced differences in SS, PT, and LL, suggesting the existence of age and sex variations, and its role to be considered when planning for spinal realignment surgeries. Clinical outcome studies are required to ascertain the impact of these findings.

Dislocation Following Anterior and Posterior Total Hip Arthroplasty in the Setting of Spinal Deformity and Stiffness: Evolving Trends Using a High-Risk Protocol at a Single Tertiary Center.

BACKGROUND: Patients who have spinal stiffness and deformity are at the highest risk for dislocation after total hip arthroplasty (THA). Previous reports of this cohort are limited to antero-lateral and postero-lateral (PL) approaches. We investigated the dislocation rate after direct anterior (DA) and PL approach THA with a contemporary high-risk protocol to optimize stability. METHODS: We investigated patients undergoing THA who had preoperative biplanar imaging from January-December 2019. Patients were identified using radiographic criteria of spinal-stiffness (<10-degree change in sacral slope from standing to seated) and deformity (flatback deformity with >10-degree difference in pelvic incidence and lumbar lordosis). There were 367 patients identified (181 DA, 186 PL). The primary outcome was dislocation rate at 2-years postoperatively. Risk-factors for dislocation were evaluated using logistic regressions (significance level of 0.05). RESULTS: There were 6 (1.6%) dislocations in the entire cohort, with low dislocation rates for both DA (0.6%) and PL-THA (2.7%). We observed increased utilization of dual mobility with larger outer head bearings (>38 mm) with PL-THA (34.4 versus 5.0%, P < .01) and conversely increased utilization of 32-mm femoral-heads with DA-THA (39.4 versus 7.0%, P < .001). Surgical approach (PL) was not a significant risk-factor for dislocation (odds ratio: 5.03, P = .15). Patients who had a history of lumbar-fusion had 8-times higher odds for dislocation (OR: 8.20, P = .020). CONCLUSIONS: To the best of our knowledge, this is the largest series to date evaluating DA and PL-THA in the hip-spine 2B-group. Our results demonstrate lower dislocation rate than expected with either surgical approach using a high-risk protocol.

Clinical Significance of Lordosis Orientation on Proximal Junctional Kyphosis Development in Long-Segment Fusion Surgery for Adult Spinal Deformity.

OBJECTIVE: We sought to evaluate the clinical impact of lordosis orientation (LO) on proximal junctional kyphosis (PJK) development in adult spinal deformity surgery. METHODS: This study included 152 patients who underwent low thoracic (T9-T12) to pelvis fusion and were followed up for ≥2 years. In the literature, 6 radiographic parameters representing LO were introduced, such as uppermost instrumented vertebra (UIV) slope, UIV inclination, UIV-femoral angle (UIVFA), thoracolumbar tilt, thoracolumbar slope, and lordosis tilt. Various clinical and radiographic factors including 6 LO parameters were investigated using logistic regression analysis to identify risk factors for PJK. RESULTS: The mean age was 69.4 years, and 136 patients were females (89.5%). PJK developed in 65 patients (42.8%). Multivariate logistic regression analysis revealed that only small postoperative pelvic incidence (PI)-lumbar lordosis (LL) (odds ratio [OR] = 0.962, 95% confidence interval: 0.929-0.996, P = 0.030) and large UIVFA (OR = 1.089, 95% confidence interval: 1.028-1.154, P = 0.004) were significant for PJK development. UIVFA showed significantly positive correlation with pelvic tilt (CC = 0.509), thoracic kyphosis (CC = 0.384), and lordosis distribution index (CC = 0.223). UIVFA was also negatively correlated with sagittal vertical axis (CC = -0.371). However, UIVFA did not correlate with LL, PI-LL, or T1 pelvic angle. CONCLUSIONS: LO significantly increases the risk of PJK development in ASD surgery. Multivariate analysis revealed that smaller postoperative PI-LL and greater UIVFA were significant risk factors for PJK. Surgeons should avoid undercorrection and overcorrection to prevent PJK development.

Loss of cervical lordosis in chronic neck pain patients with fibromyalgia: A cross-sectional study.

BACKGROUND: Some interrelationships among fibromyalgia (FM), loss of cervical lordosis (LCL), and headache have been reported. Thus, it is sensible to examine LCL as a factor underlying FM and headache. OBJECTIVE: In this study we aimed to assess LCL in chronic neck pain patients (CNPP) with FM and its association with headache features and FM severity. METHODS: CNPP with (n= 55; mean age 40.0 ± 8.5; range 20 to 55 years) and without FM (n= 55; mean age 38.5 ± 8.9; range 20 to 55 years) were included in the study. Cervical lordosis was assessed by measuring the Cobb angle on the lateral cervical radiographs. The patients were asked about headache features within the last month. In addition, the CNPP with FM were evaluated by the Turkish version of the Revised Fibromyalgia Impact Questionnaire. RESULTS: There were no statistically significant differences between the groups in terms of age, weight, height, body mass index, working status, and neck pain duration (p> 0.05 for each). The CNPP with FM had significantly reduced cervical lordosis angle compared with those without. The CNPP with FM had significantly higher headache frequency than those without (p= 0.008). There was statistically significant negative correlation between cervical lordosis angle and headache frequency in the CNPP with FM (r: -0.336; p= 0.012). CONCLUSION: According to the results of this study, LCL may be associated with FM and headache frequency in the CNPP with FM.

Factors Associated With Loss of Cervical Lordosis After Laminoplasty for Patients With Cervical Ossification of the Posterior Longitudinal Ligament: Data From a Prospective Multicenter Study.

STUDY DESIGN: A prospective multicenter study. OBJECTIVE: The objective of this study was to investigate the incidence of loss of cervical lordosis after laminoplasty for cervical ossification of the posterior longitudinal ligament (OPLL). We also sought to determine associated risk factors and the relationship with patient-reported outcomes. SUMMARY OF BACKGROUND DATA: Loss of cervical lordosis is a sequelae often observed after laminoplasty, which may adversely impact surgical outcomes. Cervical kyphosis, especially in OPLL, is associated with reoperation, but risk factors and relationship to postoperative outcomes remain understudied at this time. MATERIALS AND METHODS: This study was conducted by the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. We included 165 patients who underwent laminoplasty and completed Japanese Orthopaedic Association (JOA) score or Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaires (JOACMEQ), as well as Visual Analog Scales (VAS) for pain, with imaging. The participants were divided into two groups: those with loss of cervical lordosis of >10° or 20° after surgery and those without loss of cervical lordosis. A paired t test was applied to evaluate the association between changes in cervical spinal angles, range of motion, and cervical JOA and VAS scores before and at 2 years postoperatively. Mann-Whitney U test was used for JOACMEQ. RESULTS: Postoperative loss of cervical lordosis >10° and >20° was observed in 32 (19.4%) and 7 (4.2%), respectively. JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small extension range of motion (eROM) was significantly associated with postoperative loss of cervical lordosis, and the cutoff values of eROM were 7.4° [area under the curve (AUC): 0.76] and 8.2° (AUC: 0.92) for loss of cervical lordosis >10° and >20°, respectively. A large occupation ratio of OPLL was also associated with loss of cervical lordosis, with a cutoff value of 39.9% (AUC: 0.94). Laminoplasty resulted in functional improvement in most patient-reported outcomes; however, neck pain and bladder function tended to become worse postoperatively in cases with postoperative loss of cervical lordosis >20°. CONCLUSIONS: JOA, JOACMEQ, and VAS scores were not significantly different between those with, and without, loss of cervical lordosis. Preoperative small eROM and large OPLL may represent factors associated with loss of cervical lordosis after laminoplasty in patients with OPLL.

Obesity in children with low back pain: implications with imaging phenotypes and opioid use.

BACKGROUND CONTEXT: Low back pain (LBP) is common in children and adolescents, carrying substantial risk for recurrence and continuation into adulthood. Studies have linked obesity to the development of pediatric LBP; however, its association with lumbar spine degeneration, alignment parameters, and opioid use remains debated. PURPOSE: Considering the increasing prevalence of pediatric obesity and LBP and the inherent issues with opioid use, this study aimed to assess the association of obesity with lumbar spine degeneration, spinopelvic alignment, and opioid therapy among pediatric patients. STUDY DESIGN/SETTING: A retrospective study of pediatric patients presenting to a single institute with LBP and no history of spine deformity, tumor, or infection was performed. PATIENT SAMPLE: A totasl of 194 patients (mean age: 16.7±2.3 years, 45.3% male) were included, of which 30 (15.5%) were obese. OUTCOME MEASURES: Prevalence of imaging phenotypes and opioid use among obese to nonobese pediatric LBP patients. Magnetic resonance and plain radiographic imaging were evaluated for degenerative phenotypes (disc bulging, disc herniation, disc degeneration [DD], high-intensity zones [HIZ], disc narrowing, Schmorl's nodes, endplate phenotypes, Modic changes, spondylolisthesis, and osteophytes). Lumbopelvic parameters including lumbar lordosis, pelvic tilt, sacral slope, pelvic incidence and pelvic incidence-lumbar lordosis (PI-LL) mismatch were also examined. METHODS: Demographic and clinical information was recorded, including use of opioids. The associations between obesity and lumbar phenotypes or opiod use were assessed by multiple regression models. RESULTS: Based on multivariate analysis, obesity was significantly associated with the presence of HIZ (adjusted OR: 5.36, 95% CI: 1.30 to 22.09). Further analysis demonstrated obesity (adjusted OR: 3.92, 95% CI: 1.49 to 10.34) and disc herniation (OR: 4.10, 95% CI: 1.50 to 11.26) were associated with opioid use, independent of duration of symptoms, other potential demographic determinants, and spinopelvic alignment. CONCLUSIONS: In pediatric patients, obesity was found to be significantly associated with HIZs of the lumbar spine, while disc herniation and obesity were associated with opioid use. Spinopelvic alignment parameters did not mitigate any outcome. This study underscores that pediatric obesity increases the risk of developing specific degenerative spine changes and pain severity that may necessitate opioid use, emphasizing the importance of maintaining healthy body weight in promoting lumbar spine health in the young.

Surgical Outcomes of Cerebral Palsy Patients With Scoliosis and Lumbar Hyperlordosis: A Comparative Analysis With 2-year Minimum Follow-up.

STUDY DESIGN: Retrospective review of a prospectively collected multicenter database. OBJECTIVE: To compare outcomes of patients with cerebral palsy (CP) who undergo surgery for scoliosis with normal lordosis (NL) versus hyperlordosis. SUMMARY OF BACKGROUND DATA: Surgical correction of scoliosis with lumbar hyperlordosis is challenging. Hyperlordosis may confer higher perioperative morbidity, but this is not well understood. MATERIALS AND METHODS: A multicenter database was queried for CP patients who underwent surgery from 2008 to 2017. The minimum follow-up was 2 years. Two groups were identified: lumbar lordosis <75° (NL) versus ≥ 75° hyperlordosis (HL). Perioperative, radiographic, and clinical outcomes were compared. RESULTS: Two hundred seventy-five patients were studied: 236 NL and 39 HL (-75 to -125°). The mean age was 14.1 years, and 52.4% were male. Patients with hyperlordosis had less cognitive impairment (76.9% vs. 94.0%, P =0.008) and higher CPCHILD scores (59.4 vs. 51.0, P =0.003). Other demographics were similar between the groups. Patients with hyperlordosis had greater lumbar lordosis (-90.5 vs. -31.5°, P <0.001) and smaller sagittal vertical axis (-4.0 vs. 2.6 cm, P <0.001). Patients with hyperlordosis had greater estimated blood loss (2222.0 vs. 1460.7 mL, P <0.001) but a similar perioperative complication rate (20.5% vs. 22.5%, P =0.787). Significant correction of all radiographic parameters was achieved in both groups. The HL group had postoperative lumbar lordosis of -68.2° and sagittal vertical axis of -1.0 cm. At a 2-year follow-up, patients with hyperlordosis continued to have higher CPCHILD scores and gained the greatest benefit in overall quality of life measures (20.0 vs. 6.1, P =0.008). The reoperation rate was 10.2%: implant failure (3.6%), pseudarthrosis (0.7%), and wound complications (7.3%). There were no differences in the reoperation rate between the groups. CONCLUSION: Surgical correction of scoliosis with hyperlordosis is associated with greater estimated blood loss but similar radiographic results, perioperative morbidity, and reoperation rate as normal lordosis. Patients with hyperlordosis gained greater overall health benefits. Correction of ≥25% of hyperlordosis seems satisfactory. LEVEL OF EVIDENCE: 3.

Outcomes and Safety of Traditional Growing Rod Technique in the Treatment of Early-onset Dystrophic Scoliosis Secondary to Type 1 Neurofibromatosis With Intraspinal Rib Head Dislocation in Children.

PURPOSE: The purpose of this study was to investigate the outcomes and safety of traditional growing rod (TGR) in the treatment of early-onset dystrophic scoliosis secondary to type 1 neurofibromatosis (NF1-EOS) with intraspinal rib head dislocation (IRH) in children. METHODS: From September 2006 to June 2020, 21 patients with NF1-EOS were treated with TGR. The patients comprised 13 boys and 8 girls with a mean age of 7.1±1.5 years. Two patients had IRH-induced nerve injury [American Spinal Injury Association (ASIA) grade D]. No neurological symptoms were found in the other patients. The intraspinal rib proportion, apical vertebral rotation, apical vertebral translation, coronal main thoracic curve, trunk shift, thoracic kyphosis, lumbar lordosis, sagittal balance, and T1-S1 height were measured before and after TGR implantation and at the last follow-up. Complications were also evaluated. RESULTS: The mean follow-up time was 3.4±2.0 years. An average of 3.1 times (range: 1 to 8 times) lengthening procedures were performed in each patient. The intraspinal rib proportion was significantly lower postoperatively than preoperatively (22±11% vs. 33±18%, respectively; P <0.001), and no significant correction loss was found at the last follow-up (24±12%, P= 0.364). Compared with the measurements before TGR implantation, the major coronal curve and T1-S1 height after TGR implantation and at the last follow-up were significantly different ( P <0.05). Significant correction of apical vertebral translation, thoracic kyphosis, lumbar lordosis, and sagittal balance were noted after TGR implantation, and no significant correction loss was found at the last follow-up ( P >0.05). Ten complications occurred in 7 patients. Two patients with nerve injury recovered after the operation. No neurological complications were found during the follow-up. CONCLUSIONS: TGR is a safe and effective therapy for NF1-EOS with IRH where there was no direct compression of the spinal cord, which was confirmed by preoperative magnetic resonance imaging. Through this procedure, IRH could be partly removed from the spinal canal. LEVEL OF EVIDENCE: Level III.

Surgical Correction of Distal Junctional Kyphosis.

Distal junctional kyphosis (DJK) is defined as the development of a kyphotic angulation over 10 degrees below a fusion construct and has been described as a complication of the treatment of adolescent idiopathic scoliosis, Scheuermann kyphosis, adult spinal deformity, and cervical deformity. There are some inherent risk factors to DJK: multilevel fusions, damage to the midline soft tissues including interspinous/supraspinous ligaments, T5-T12 thoracic kyphosis, T11-L2 thoracolumbar kyphosis, and increased mismatch between cervical lordosis and T1 slope. A 53-year-old male presented with cervicalgia, inability to sustain horizontal gaze, and kyphosis-enabled forward head posture. He underwent C3-T1 posterior decompression and fusion as treatment for cervical myelopathy 18 months prior. Neurologic examination was normal, with appreciable protrusion of the T1 vertebral spinous process. Surgery was initiated through subperiosteal exposure of C2-T6, followed by removal of previously set instrumentation, placement of new screws, and posterior column osteotomies of selected segments. Final steps involved compression across excised portions, locking pedicle screws, and a multirod insertion after closure of the posterior column osteotomies by compression maneuvers. Correction for DJK encompasses sagittal alignment restoration, a stable construct, and a good biological environment for healing. Failure of DJK realignment can occur if the patient's ligaments deteriorate distal to the construct or fractures develop in vertebral bodies at the lowest instrumented vertebra or lowest instrumented vertebra +1. One year after surgery, the patient's condition improved, evidenced from both patient self-report and a standing posture radiograph.

High Prevalence of Spinopelvic Risk Factors in Patients With Post-Operative Hip Dislocations.

BACKGROUND: Excessive standing posterior pelvic tilt (PT), lumbar spine stiffness, low pelvic incidence (PI), and severe sagittal spinal deformity (SSD) have been linked to increased dislocation rates. We aimed to determine the prevalence of these 4 parameters in a cohort of unstable total hip arthroplasty (THA) patients and compare these to a large representative control population of primary THA patients. METHODS: Forty-eight patients with instability following primary THA were compared to a control cohort of 9414 THA patients. Lateral X-rays in standing and flexed-seated positions were used to assess PT and lumbar lordosis (LL). Computed tomography scans were used to measure PI and acetabular cup orientation. Thresholds for "at risk" spinopelvic parameters were standing posterior PT ≤ -15°, lumbar flexion (LLstand-LLseated) ≤ 20°, PI ≤ 41°, PI ≥ 70°, and SSD (PI-LLstand mismatch ≥ 20°). RESULTS: There were significant differences in mean spinopelvic parameters between the dislocating and control cohorts (P < .001). There were no differences in mean PI (58° versus 56°, respectively, P = .29) or prevalence of high and low PI between groups. 67% of the dislocating patients had one or more significant risk factors, compared to only 11% of the control. A total of 71% of the dislocating patients had cup orientations within the traditional safe zone. CONCLUSION: Excessive standing posterior PT, low lumbar flexion, and a severe SSD are more prevalent in unstable THAs. Pre-op screening for these parameters combined with appropriate planning and implant selection may help identify at risk patients and reduce the prevalence of dislocation.

Pelvic Nonresponse Following Treatment of Adult Spinal Deformity: Influence of Realignment Strategies on Occurrence.

PURPOSE: Despite adequate correction, the pelvis may fail to readjust, deemed pelvic nonresponse (PNR). To assess alignment outcomes [PNR, proximal junctional kyphosis (PJK), postoperative cervical deformity (CD)] following adult spinal deformity (ASD) surgery utilizing different realignment strategies. MATERIALS AND METHODS: ASD patients with two-year data were included. PNR defined as undercorrected in age-adjusted pelvic tilt (PT) at six weeks and maintained at two years. Patients classified by alignment utilities: (a) improvement in Scoliosis Research Society-Schwab sagittal vertical axis, (b) matching in age-adjusted pelvic incidence-lumbar lordosis, (c) matching in Roussouly, (d) aligning Global Alignment and Proportionality (GAP) score. Multivariable regression analyses, controlling for age, baseline deformity, and surgical factors, assessed rates of PNR, PJK, and CD development following realignment. RESULTS: A total of 686 patients met the inclusion criteria. Rates of postoperative PJK and CD were not significant in the PNR group (both P >0.15). PNR patients less often met substantial clinical benefit in Oswestry Disability Index by two years [odds ratio: 0.6 (0.4-0.98)]. Patients overcorrected in age-adjusted pelvic incidence-lumbar lordosis, matching Roussouly, or proportioned in GAP at six weeks had lower rates of PNR (all P <0.001). Incremental addition of classifications led to 0% occurrence of PNR, PJK, and CD. Stratifying by baseline PT severity, Low and moderate deformity demonstrated the least incidence of PNR (7.7%) when proportioning in GAP at six weeks, while severe PT benefited most from matching in Roussouly (all P <0.05). CONCLUSIONS: Following ASD corrective surgery, 24.9% of patients showed residual pelvic malalignment. This occurrence was often accompanied by undercorrection of lumbopelvic mismatch and less improvement of pain. However, overcorrection in any strategy incurred higher rates of PJK. We recommend surgeons identify a middle ground using one, or more, of the available classifications to inform correction goals in this regard. LEVEL OF EVIDENCE: III.

The Impact of Upper Instrumented Vertebra Orientation on Proximal Junctional Kyphosis: A Novel and Fixed Parameter, Fused Spinopelvic Angle.

STUDY DESIGN: A retrospective study. OBJECTIVES: To evaluate the impact of upper instrumented vertebra (UIV) orientation including the fused spinopelvic angle (FSPA) on proximal junctional kyphosis (PJK). SUMMARY OF BACKGROUND DATA: PJK is a challenging complication after adult spinal deformity (ASD) surgery. Some studies proposed UIV orientation act as a risk factor of PJK, but there remain debates because UIV orientation is changed by position. Therefore, we investigated the relationship between the FSPA, a novel parameter for the relationship between UIV and pelvis which did not change by position, and PJK. MATERIALS AND METHODS: ASD patients who underwent long-segment fusion to the pelvis and followed up for more than two years were included. Comparative analysis was performed on spinopelvic parameters including UIV orientation parameters (UIV slope angle and FSPA) between PJK and non-PJK group. Binary regression analysis was conducted to find out the risk factors for PJK. And correlation analysis was conducted to find out the parameters that affect the FSPA. RESULTS: A total of 190 patients were included. PJK incidence was 13.2% (25/190). PJK group showed a significantly greater postoperative UIV slope (21.3° vs. 18.8°, P =0.041) and significantly lesser postoperative FSPA (-0.9° vs. 4.5°, P <0.001). In binary regression analysis, only FSPA acted as a risk factor of PJK (odds ratio=0.920, P =0.004). The FSPA has strong positive correlation with pelvic incidence (PI)-lumbar lordosis (LL) ( r =0.666, P <0.001) and negative correlation with lordosis distribution index (LDI) ( r =-0.228, P =0.004). CONCLUSION: The FSPA is a fixed parameter which is not dependent on position. A reduction of the FSPA increases the risk for PJK. The FSPA can be adjusted through PI-LL and LDI. Thus, surgeons should increase the FSPA by adjusting the PI-LL and LDI during ASD surgery to prevent PJK.

A randomized controlled study of two different fixations in anterior cervical discectomy of multilevel cervical spondylotic myelopathy.

Background: To compare the efficacy of anterior cervical discectomy and hybrid fusion (ACDHF) with short-segment plate plus self-locking, stand-alone intervertebral cages versus traditional anterior cervical discectomy and fusion (ACDF) with long-segment plate for multilevel cervical spondylotic myelopathy (MCSM). Methods: All the patients were randomly divided into two groups. 30 cases underwent ACDHF with short-segment plate and self-locking stand-alone cages (hybrid group), while the other 30 cases received ACDF with long-segment plate (control group). In patients meeting the inclusion and exclusion criteria, operation time, blood loss, postoperative drainage volume, length of stay (LOS), visual analogue scale for neck pain (VASNP) scores, Japanese Orthopaedic Association (JOA) score, and the cervical lordosis before and after the operation (5 days, 3, 6, 12 months after operation and final follow-up) were evaluated. The postoperative complications were analyzed as well. Results: All operations were performed uneventfully with followed-up. Compared with ACDF, ACDHF showed a shorter operation time, less intraoperative blood loss and postoperative drainage (p < 0.05). There were no significant difference in LOS between two groups (p ˃ 0.05). Both approaches significantly improved the JOA scores, VASNP scores and the cervical lordosis (p < 0.05). Based on Bazaz grading system, hybrid group had a lower incidence of dysphagia than control group in follow-up periods of 5 days, 3 and 6 months (p < 0.05). Conclusion: ACDF and ACDHF are both effective methods of restoring cervical lordosis following MCSM, but hybrid surgery minimizes intraoperative injury and postoperative dysphagia, making it a viable treatment option for the disorder.

A predictive scoring system for proximal junctional kyphosis after posterior internal fixation in elderly patients with chronic osteoporotic vertebral fracture: A single-center diagnostic study.

Objective: To establish a predictive scoring system for proximal junctional kyphosis (PJK) after posterior internal fixation in elderly patients with chronic osteoporotic vertebral fracture (COVF). Materials and methods: The medical records of 88 patients who were diagnosed with COVF and underwent posterior internal fixation in our hospital from January 2013 to December 2017 were retrospectively analyzed. The included patients were divided into two groups according to whether they suffered PJK after surgery, namely, the PJK group (25 cases) and non-PJK group (63 cases). The following clinical characteristics were recorded and analyzed: age, gender, body mass index (BMI), bone mineral density (BMD), smoking history, fracture segment, proximal junction angle, sagittal vertebral axis, pelvic incidence (PI)-lumbar lordosis (LL), pelvic tilt (PT), sacral slope (SS), posterior ligamentous complex (PLC) injury, upper instrumented vertebra, lower instrumented vertebra, and the number of fixed segments. The prevalence of these clinical characteristics in the PJK group was evaluated, and the scoring system was established using logistic regression analysis. The performance of the scoring system was also prospectively validated. Results: The predictive scoring system was established based on five clinical characteristics confirmed as significant predictors of PJK, namely, age > 70 years, BMI > 28 kg/m2, BMD < -3.5 SD, preoperative PI-LL > 20°, and PLC injury. PJK showed a significantly higher score than non-PJK (7.80 points vs. 2.83 points, t=9.556, P<0.001), and the optimal cutoff value for the scoring system was 5 points. The sensitivity and specificity of the scoring system for predicting postoperative PJK were 80.00% and 88.89%, respectively, in the derivation set and 75.00% and 80.00% in the validation set. Conclusion: The predictive scoring system was confirmed with satisfactory sensitivity and specificity in predicting PJK after posterior internal fixation in elderly COVF patients. The risk of postoperative PJK in patients with a score of 6-11 is high, while the score of 0-5 is low.

Neuromuscular lordoscoliosis: an unusual response to post-operative halo-gravity traction.

PURPOSE: To report the results of prolonged post-operative halo-gravity traction in a patient in whom the surgery had to be interrupted unexpectedly and for whom subsequently specific clinical circumstances contraindicated completion of the surgical procedure. METHODS: The patient was a 15-year-old male with severe cervico-dorsolumbar lordoscoliosis who was being studied for associated diffuse axonal injury. He performed halo-gravity traction for 12 weeks. Subsequent surgical management consisted of occipito-lumbar posterior instrumented fusion. During the surgical approach, electrocardiographic changes with hemodynamic decompensation were detected that did not improve with anesthetic reanimation. The intervention was stopped, the surgical wound was closed, and the patient was transferred to the intensive care unit (ICU). It was decided that a revision surgery with the aim to continue with the previous strategy would imply a high risk of perioperative morbidity and mortality. RESULTS: Orthopedic management was decided upon consisting of continued halo-gravity traction with wheelchair modification at home, which was extended to a period of 12 months because of the good results obtained in terms of cervicothoracic realignment. Two years after halo-gravity discontinuation, clinical and radiographic occipito-cervical alignment was good and the patient conserved certain occipito-cervical range of motion and had the capacity of maintaining a horizontal gaze. CONCLUSION: We considered the outcome extraordinary and relevant in this complex and unusual patient. A longer follow-up will provide more data regarding the final outcome of this treatment.

Standalone cage versus anchored cage for anterior cervical discectomy and fusion: a comparative analysis of clinical and radiological outcomes.

PURPOSE: The use of standalone cages (SAC) and anchored cages (AC) in anterior cervical discectomy and fusion surgery (ACDF) has shown advantage of reduced operative time and lower incidence of dysphagia. However, there is limited literature available comparing the clinical and radiological outcomes of SAC and AC. METHODS: We conducted a prospective study for patients undergoing ACDF for cervical radiculopathy or myelopathy. Patient were classified based on the cage used into SAC group and the AC group. Clinical outcomes were assessed using the modified Japanese Orthopedic Association (mJOA) for myelopathy and Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for radiculopathy. Dysphagia was graded as per Bazaz score. Radiologically, global cervical lordosis, segmental lordosis, cage subsidence, and migration were assessed. RESULTS: We analyzed 31 patients in each group with a minimum two year follow-up. The mean VAS improved from 7.9 to 4.56, mean NDI score improved from 27.6 to 19.8, and mean mJOA improved from 10.8 to 11.7 which were statistically significant (p < 0.05); however, no significant difference was noted between the SAC and AC groups. Mean global lordosis improved from 14.4 to 20.3° and mean segmental lordosis improved from 6 to 10.1° at six months and plateaued to 6.9° at final follow up without any significant difference between the groups. The subsidence was statistically more in 12.9% (4/31) in SAC than 6.4% (2/31) in AC. CONCLUSION: AC showed of lower rates of subsidence while both SAC and AC had comparable clinical outcomes and radiological alignment outcomes.