Impact of osteosclerosis on cervical pedicle screw insertion using preoperative CT-based navigation.

PURPOSE: Preoperative computed tomography (CT)-based navigation is used for cervical pedicle screw (CPS) insertion to mitigate the risk of spinal cord and vertebral artery injury. In vertebrae with osteosclerosis due to degeneration or other factors, however, probing may not proceed easily, with difficulty creating the CPS insertion hole. This study investigated the impact of osteosclerosis on the accuracy of CPS insertion. METHODS: A total of 138 patients with CPS inserted at the C3-C7 level using preoperative CT navigation were retrospectively analyzed. Pre- and postoperative CT was employed to investigate screw position and Hounsfield unit (HU) values at the lateral mass to evaluate the degree of osteosclerosis in the CPS insertion pathway. RESULTS: Among 561 CPS insertions, the Grade 3 perforation rate was 1.8%, and the Grade 2 or higher perforation rate was 8.0%. When comparing insertions with and without CPS perforation, HU values were significantly higher in the perforation group (578 ± 191 vs. 318 ± 191, p < 0.01). The frequency of CPS insertion into the mid-cervical spine was also significantly greater in the perforation group (68.9% vs. 62.5%, p < 0.01). Logistic regression analysis revealed that a high HU value at the lateral mass (odds ratio 1.09, 95% confidence interval: 1.07-1.11, p < 0.01) was a significant independent factor associated with CPS deviation. CONCLUSIONS: The screw perforation rate of Grade 2 or higher in CPS insertion using preoperative CT-based navigation was 8.0%. Since osteosclerosis was an independent factor related to CPS deviation, additional care may be required during insertion into affected vertebrae.

Neurological recovery rate and predictive factors of incomplete AIS grade C spinal cord injury in the older aged population.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To define the prognosis and predictive factors for neurological improvement in older patients with incomplete spinal cord injury (SCI) of American Spinal Injury Association Impairment Scale grade C (AIS-C). SETTINGS: Multi-institutions in Japan. METHODS: We included patients aged ≥65 years with traumatic SCI of AIS-C who were treated conservatively or surgically with >3 follow-up months. To identify factors related to neurological improvement, patients were divided into three groups according to their neurological status at the final follow-up, with univariate among-group comparisons of demographics, radiographic, and therapeutic factors. Significant variables were included in the multivariate logistic regression analysis. RESULTS: Overall, 296 older patients with SCI of AIS-C on admission were identified (average age: 75.2 years, average follow-up: 18.7 months). Among them, 190 (64.2%) patients improved to AIS-D and 21 (7.1%) patients improved to AIS-E at final follow-up. There were significant among-group differences in age (p = 0.026), body mass index (p = 0.007), status of pre-traumatic activities of daily living (ADL) (p = 0.037), and serum albumin concentrations (p = 0.011). Logistic regression analysis showed no significant differences in variables in the stratified group of patients who improved to AIS-D. Meanwhile, serum albumin was a significant variable in patients who improved to AIS-E (p = 0.026; OR: 6.20, pre-traumatic ADL was omitted due to data skewness). CONCLUSIONS: Most older patients with incomplete AIS-C SCI demonstrated at least 1 grade of neurological improvement. However, <10% of patients achieved complete recovery. Key predictors of complete recovery were high serum albumin levels on admission and independent pre-traumatic ADL. SPONSORSHIP: No funding was received for this study.

Association between restricted outings and geriatric locomotive function scale score in the general elderly population during the COVID-19 pandemic.

BACKGROUND: Restrictions in daily activities due to coronavirus infection countermeasures reduced opportunities for physical activity and social participation in people of all ages. This study investigated the associations of restricted outings on locomotive function during the COVID-19 pandemic using a cohort of middle-aged and elderly community-dwelling residents. METHODS: Registered citizens of 50-89 years old were targeted for this investigation. We established 8 groups based on age (50's, 60's, 70's, and 80's) and gender (male and female) after random sampling from the basic resident registry of Obuse town in 2014. All participants were surveyed by a 25-question geriatric locomotive function scale (GLFS-25) at the time of checkup before the COVID-19 pandemic. Then, in 2021 and 2022 after government restrictions on outings were lifted for COVID-19 pandemic, all participants were mailed questionnaires including the GLFS-25. A total of 296 (143 male and 153 female) participants who responded at least once were included. We evaluated the changes in opportunities to go out between pre- and post-pandemic time points and the impact on GLFS-25 scores. RESULTS: In total, 128 (43.2%) respondents had fewer opportunities to go out than the previous year. Pre- and post-pandemic GLFS-25 scores in the decreased outing (+) group were significantly worse than in the decreased outing (-) group (both p < 0.01). The final multivariate model revealed GLFS-25 score worsening beta coefficient of 0.27 for age (+10 years), 3.97 for male, 4.54 for decreased outings, and 4.46 for spinal canal stenosis. CONCLUSIONS: In this randomly sampled Japanese cohort based on a resident registry, restricted outings during the COVID-19 pandemic was a significant independent factor associated with lower locomotive function.

Influence of the timing of surgery for cervical spinal cord injury without bone injury in the elderly: A retrospective multicenter study.

BACKGROUND: Although previous studies have demonstrated the advantages of early surgery for traumatic spinal cord injury (SCI), the appropriate surgical timing for cervical SCIs (CSCIs) without bone injury remains controversial. Here, we investigated the influence of relatively early surgery within 48 h of injury on the neurological recovery of elderly patients with CSCI and no bone injury. METHODS: In this retrospective multicenter study, we reviewed data from 159 consecutive patients aged ≥65 years with CSCI without bone injury who underwent surgery in participating centers between 2010 and 2020. Patients were followed up for at least 6 months following CSCI. We divided patients into relatively early (≤48 h after CSCI, n = 24) and late surgery (>48 h after CSCI, n = 135) groups, and baseline characteristics and neurological outcomes were compared between them. Multivariate analysis was performed to identify factors associated with neurological recovery. RESULTS: The relatively early surgery group demonstrated a lower prevalence of cardiac disease, poorer baseline American Spinal Injury Association (ASIA) impairment scale grade, and lower baseline ASIA motor score (AMS) than those of the late surgery group (P < 0.030, P < 0.001, and P < 0.001, respectively). Although the AMS was lower in the relatively early surgery group at 6 months following injury (P = 0.001), greater improvement in this score from baseline to 6-months post injury was observed (P = 0.010). Multiple linear regression analysis revealed that relatively early surgery did not affect postoperative improvement in AMS, rather, lower baseline AMS was associated with better AMS improvement (P < 0.001). Delirium (P = 0.006), pneumonia (P = 0.030), and diabetes mellitus (P = 0.039) negatively influenced postoperative improvement. CONCLUSIONS: Although further validation by future studies is required, relatively early surgery did not show a positive influence on neurological recovery after CSCI without bone injury in the elderly.

Reduction in CT scan number with the reference frame middle attachment method in intraoperative CT navigation for adolescent idiopathic scoliosis.

PURPOSE: Elucidate whether it is preferable to use the reference frame (RF) middle attachment (RFMA) method over the edge of the planned pedicle screw (PS) insertion area for RF placement in the surgery for adolescent idiopathic scoliosis (AIS) with intraoperative computed tomography (CT) navigation. METHODS: Eighty-six consecutive patients (76 female and 10 male; mean age: 15.9 years) with AIS who underwent posterior spinal fusion using intraoperative CT navigation were enrolled. The group with the RF placed at the most distal part of the CT scan range was defined as the distal group (Group D), with other placements classified into the middle group (Group M). PS perforation rate and surgical outcome were compared between the groups. RESULTS: There was no significant difference in perforation rate between Group M and Group D (3.4% vs. 3.0%, P = 0.754). The mean ± standard deviation number of instrumented vertebrae at the first CT scan was significantly higher in Group M (8.2 ± 1.2 vs. 6.3 ± 1.2, P < 0.001), while mean blood loss was significantly lower (266 ± 185 mL vs. 416 ± 348 mL, P = 0.011). The frequency of needing a second CT scan for PS insertion was significantly lower in Group M (38% vs. 69%, P = 0.04). CONCLUSION: The RFMA method in thoracic scoliosis surgery for AIS with intraoperative CT navigation could significantly decrease the number of CT scans and blood loss while maintaining a comparable PS perforation rate to RF placement at the distal end of the planned PS insertion range.

Comparison of spinous process-splitting laminectomy versus posterolateral fusion for lumbar degenerative spondylolisthesis.

BACKGROUND: Although several studies have recently shown that spinous process-splitting laminectomy (SPSL) maintains lumbar spinal stability by preserving posterior ligament components and paraspinal muscles as compared with conventional laminectomy, evidence is scarce on the treatment outcomes of SPSL limited to lumbar degenerative spondylolisthesis. We herein compare the surgical results and global alignment changes for SPSL versus posterolateral lumbar fusion (PLF) without instrumentation for lumbar degenerative spondylolisthesis. METHODS: A total of 110 patients with Grade 1 lumbar degenerative spondylolisthesis who had undergone SPSL (47 patients) or PLF (63 patients) with minimum 1-year follow-up were retrospectively enrolled from a single institutional database. RESULTS: Mean operating time per intervertebral level and intraoperative blood loss per intervertebral level were comparable between the SPSL group and PLF group. Japanese Orthopaedic Association scores, Oswestry disability index, and visual analog scale scores were significantly and comparably improved at 1 year postoperatively in both groups as compared with preoperative levels. The numbers of vertebrae with slip progression to Grade 2 and slip progression of 5% or more at 1 year postoperatively were similar between the groups. In the SPSL group, mean pelvic tilt (PT) was significantly decreased at 1 year postoperatively. In the PLF group, mean lumbar lordosis (LL) was significantly increased, while mean sagittal vertical axis, PT, and pelvic incidence-LL were significantly decreased at 1 year after surgery. CONCLUSIONS: Compared with PLF without instrumentation, SPSL for Grade 1 lumbar degenerative spondylolisthesis displayed comparable results for slip progression and clinical outcomes at 1 year postoperatively.

Prognostic impact of respiratory dysfunction in elderly patients with cervical spinal cord injury and/or fractures: a multicenter survey.

PURPOSE: To investigate the impact of early post-injury respiratory dysfunction for neurological and ambulatory ability recovery in patients with cervical spinal cord injury (SCI) and/or fractures. METHODS: We included 1,353 elderly patients with SCI and/or fractures from 78 institutions in Japan. Patients who required early tracheostomy and ventilator management and those who developed respiratory complications were included in the respiratory dysfunction group, which was further classified into mild and severe respiratory groups based on respiratory weaning management. Patient characteristics, laboratory data, neurological impairment scale scores, complications at injury, and surgical treatment were evaluated. We performed a propensity score-matched analysis to compare neurological outcomes and mobility between groups. RESULTS: Overall, 104 patients (7.8%) had impaired respiratory function. In propensity score-matched analysis, the respiratory dysfunction group had a lower home discharge and ambulation rates (p = 0.018, p = 0.001, respectively), and higher rate of severe paralysis (p < 0.001) at discharge. At the final follow-up, the respiratory dysfunction group had a lower ambulation rate (p = 0.004) and higher rate of severe paralysis (p < 0.001). Twenty-six patients with severe disability required respiratory management for up to 6 months post-injury and died of respiratory complications. The mild and severe respiratory dysfunction groups had a high percentage of severe paraplegic cases with low ambulatory ability; there was no significant difference between them. The severe respiratory dysfunction group tended to have a poorer prognosis. CONCLUSION: Respiratory dysfunction in elderly patients with SCI and/or cervical fracture in the early post-injury period reflects the severity of the condition and may be a useful prognostic predictor.

Composite hemangioendothelioma in the cervical spine with kaposiform hemangioendothelioma features in an elderly patient: a case report.

BACKGROUND: Composite hemangioendothelioma (CHE) is an intermediate group of tumors with features between hemangioma and angiosarcoma both histologically and biologically. CHE is predominant in young and middle-aged adults, but very infrequently affects the spine. We describe the case of primary CHE in the cervical spine exhibiting kaposiform hemangioendothelioma (KHE)-like components that was associated with cervical myelopathy with vertebral body destruction in an elderly woman. We retrospectively reviewed the case of a primary cervical spinal tumor, diagnosed as CHE with KHE-like components in pathological findings, associated with cervical myelopathy and cervical vertebral body destruction. CASE PRESENTATION: An 80-year-old woman presented with progressive cervical myelopathy caused by a cervical spine tumor. Preoperative cervical MRI revealed a neoplastic lesion invading the cervical spine that strongly compressed the spinal cord, causing right upper-limb paralysis. We performed partial tumor resection along with posterior decompression and fixation. Postoperatively, pathological findings showed that the tumor was CHE with KHE-like features. Following radiotherapy, no recurrences have been observed in 21 months. CONCLUSIONS: This is the first report of CHE with features of KHE in the spine of an elderly patient. Posterior decompression and fusion of the cervical spine and subsequent radiotherapy resulted in a good outcome.

Does surgery improve neurological outcomes in older individuals with cervical spinal cord injury without bone injury? A multicenter study.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To investigate the neurological outcomes of older individuals treated with surgery versus conservative treatment for cervical spinal cord injury (CSCI) without bone injury. SETTING: Thirty-three medical institutions in Japan. METHODS: This study included 317 consecutive persons aged ≥65 years with CSCI without bone injury in participating institutes between 2010 and 2020. The participants were followed up for at least 6 months after the injury. Individuals were divided into surgery (n = 114) and conservative treatment (n = 203) groups. To compare neurological outcomes and complications between the groups, propensity score matching of the baseline factors (characteristics, comorbidities, and neurological function) was performed. RESULTS: After propensity score matching, the surgery and conservative treatment groups comprised 89 individuals each. Surgery was performed at a median of 9.0 (3-17) days after CSCI. Baseline factors were comparable between groups, and the standardized difference in the covariates in the matched cohort was <10%. The American Spinal Injury Association (ASIA) impairment scale grade and ASIA motor score (AMS) 6 months after injury and changes in the AMS from baseline to 6 months after injury were not significantly different between groups (P = 0.63, P = 0.24, and P = 0.75, respectively). Few participants who underwent surgery demonstrated perioperative complications such as dural tear (1.1%), surgical site infection (2.2%), and C5 palsy (5.6%). CONCLUSION: Conservative treatment is suggested to be a more favorable option for older individuals with CSCI without bone injuries, but this finding requires further validation.

Hemoptysis due to progressive scoliosis associated with congenital heart disease: a case report.

BACKGROUND: Patients with congenital heart disease (CHD) are associated with an increased incidence of scoliosis, often with severe progression. We report a case of hemoptysis caused by rapid scoliosis progression subsequent to surgery for CHD that was successfully managed by surgical curve correction following coil embolization. CASE PRESENTATION: A 14-year-old girl with scoliosis had undergone open heart surgery for CHD at the age of 1 year. She was first noted to have scoliosis at 12 years of age, which began to progress rapidly. At age 13, her main thoracic curve Cobb angle was 46°, and hemoptysis with high pulmonary vein pressure due to vertebral rotation was detected. Nine months after coil embolization, she received posterior spinal fusion from T5 to L2 for scoliosis correction. Postoperatively, her pulmonary vein diameter was enlarged, with no detectable signs of hemoptysis. CONCLUSIONS: We encountered a case of hemoptysis caused by advanced scoliosis after cardiac surgery that was successfully treated by correction of the scoliotic curve following coil embolization. Patients with secondary scoliosis after surgery for CHD should be carefully monitored for the possibility of cardiovascular system deterioration.

A multicenter study of 1-year mortality and walking capacity after spinal fusion surgery for cervical fracture in elderly patients.

BACKGROUND: The 1-year mortality and functional prognoses of patients who received surgery for cervical trauma in the elderly remains unclear. The aim of this study is to investigate the rates of, and factors associated with mortality and the deterioration in walking capacity occurring 1 year after spinal fusion surgery for cervical fractures in patients 65 years of age or older. METHODS: Three hundred thirteen patients aged 65 years or more with a traumatic cervical fracture who received spinal fusion surgery were enrolled. The patients were divided into a survival group and a mortality group, or a maintained walking capacity group and a deteriorated walking capacity group. We compared patients' backgrounds, trauma, and surgical parameters between the two groups. To identify factors associated with mortality or a deteriorated walking capacity 1 year postoperatively, a multivariate logistic regression analysis was conducted. RESULTS: One year postoperatively, the rate of mortality was 8%. A higher Charlson comorbidity index (CCI) score, a more severe the American Spinal Cord Injury Association impairment scale (AIS), and longer surgical time were identified as independent factors associated with an increase in 1-year mortality. The rate of deterioration in walking capacity between pre-trauma and 1 year postoperatively was 33%. A more severe AIS, lower albumin (Alb) and hemoglobin (Hb) values, and a larger number of fused segments were identified as independent factors associated with the increased risk of deteriorated walking capacity 1 year postoperatively. CONCLUSIONS: The 1-year rate of mortality after spinal fusion surgery for cervical fracture in patients 65 years of age or older was 8%, and its associated factors were a higher CCI score, a more severe AIS, and a longer surgical time. The rate of deterioration in walking capacity was 33%, and its associated factors were a more severe AIS, lower Alb, lower Hb values, and a larger number of fused segments.

A case of adult-onset Grisel's syndrome.

Aim: Grisel's syndrome is a non-traumatic subluxation of the atlanto-axial joint that occurs after infection or inflammation in the otolaryngological area, primarily in children.Method: This report describes the clinical characteristics of an extremely rare case of adult-onset Grisel's syndrome.Result: A 77-year-old woman presented with neck and bilateral shoulder pain and stiffness. Her temperature was 37.6 °C. Blood testing revealed a mildly elevated inflammatory response, although blood cultures were negative. Computed tomography (CT) showed atlanto-axial subluxation and joint destruction. T2-weighted magnetic resonance imaging (MRI) displayed high signals in the soft tissues in the anterior space of the atlas and axis, posterior wall of the pharynx, and interspinous ligament, indicating spinal cord compression at the C1 level. Differential diagnoses of inflammation and diseases causing atlanto-axial subluxation included rheumatoid arthritis, amyloidosis, pyogenic spondylitis due to posterior pharyngeal abscess, and crowned dens syndrome. After the systematic elimination of each condition, we considered Grisel's syndrome and began non-surgical treatment with intravenous antibiotics and a Philadelphia neck collar. Her inflammatory response and neck pain gradually decreased. Six months later, there was no progression of instability. She was able to walk unaided and live normally with the use of a neck collar as needed.Conclusion: Grisel's syndrome occurs predominantly in children, but can also afflict adults. Since early diagnosis and treatment can improve symptoms in some cases and prevent progressive atlanto-axial instability, prompt evaluation of the atlanto-axial joint using CT or MRI is advised in patients with neck pain and limited range of motion.

Pseudohypoxic brain swelling and secondary hydrocephalus with pseudomeningocele after lumbar surgery: a case report.

BACKGROUND: Postoperative intracranial complications are rare in spine surgery not including cranial procedures. We describe an uncommon case of pseudohypoxic brain swelling (PHBS) and secondary hydrocephalus after transforaminal lumbar interbody fusion (TLIF) presenting as impaired consciousness and repeated seizures. CASE PRESENTATION: A 65-year-old man underwent L4-5 TLIF for lumbar spondylolisthesis and began experiencing generalized seizures immediately postoperatively. Computed tomography (CT) revealed diffuse cerebral edema-like hypoxic ischemic encephalopathy. He was transported to our hospital, at which time epidural drainage was halted and anti-edema therapy was commenced. His impaired consciousness improved. However, he suffered secondary hydrocephalus due to continuous bleeding from a dural defect and spinal epidural fluid collection 3 months later. Following the completion of dural repair and insertion of a ventriculoperitoneal shunt, his neurologic symptoms and neuroimaging findings improved significantly. CONCLUSIONS: PHBS can be considered in patients with unexpected neurological deterioration following lumbar spine surgery even with the absence of documented durotomy. This might be due to postoperative intracranial hypotension-associated venous congestion, and to be distinguished from the more common postoperative cerebral ischemic events-caused by arterial or venous occlusions-or anesthetics complications.

Values for the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire in the general elderly population: A Japanese cohort survey randomly sampled from a basic resident registry.

BACKGROUND: Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) is widely used as a patient-based evaluation tool for lumbar spine disease in Japan. However, there are currently few established JOABPEQ reference values for the general population. This study proposes population-based reference values for JOABPEQ using a randomly sampled Japanese cohort. METHODS: Registered citizens of 50-89 years old were targeted for this survey. We established 8 groups based on age (50's, 60's, 70's, and 80's) and gender (male and female) after random sampling from the basic resident registry of Obuse town in 2014. A total of 414 participants (202 males and 212 females) were enrolled for calculations of average JOABPEQ scores for each age and gender group. We also evaluated for correlations between JOABPEQ domain scores and visual analogue scale (VAS) scores for low back pain. RESULTS: Median reference JOABPEQ scores stratified by age and gender were determined in this study. Lumbar function, walking ability, and social life function deteriorated significantly with age in both genders, with remarkable declines for the social life function domain. VAS scores for low back pain were not significantly correlated with JOABPEQ item scores. CONCLUSIONS: This first resident cohort of Japanese individuals determined median JOABPEQ scores by age and gender, which might serve as reference values for future studies.

Scoliosis in Goldenhar syndrome with curve reversal during brace treatment: a case report.

BACKGROUND: Goldenhar syndrome sometimes displays progressive scoliosis and other spinal deformities that require treatment. However, few reports exist on scoliosis correction in Goldenhar syndrome. We described the rare radiological outcomes of a patient with Goldenhar syndrome who received brace treatment for scoliosis. CASE PRESENTATION: A 4-year-old boy was diagnosed as having Goldenhar syndrome and referred to our hospital for scoliosis treatment. The deformity deteriorated gradually, and left convex scoliotic angle was 26 degrees (T3-L2) at 11 years of age. Unexpectedly during treatment with an orthopedic brace, the curve had reversed to 21 degrees (T5-L2) at 7 months of therapy. After another adjustment of the brace, his right convex scoliotic angle improved to 13 degrees (T4-L2) at 15 months of treatment. CONCLUSIONS: Curve reversal may occur during brace treatment for scoliosis in Goldenhar syndrome. Clinicians may opt to periodically check curve correction despite the risk of increased radiation exposure.

Factors leading to postoperative pain in adolescent idiopathic scoliosis patients including sagittal alignment and lumbar disc degeneration.

PURPOSE: This study examined for factors contributing to postoperative pain in adolescent idiopathic scoliosis (AIS), including those of sagittal alignment and lumbar disc degeneration. METHODS: A total of 101 consecutive patients who underwent posterior spinal fusion for AIS and who were followed for a minimum of 2 years were included in this investigation. We assessed Lenke curve type, age, Risser grade, body mass index (BMI), radiographic parameters, lumbar disc degeneration, correction rate, number of fused vertebrae, lowest instrumented vertebra, preoperative SRS-22r survey mental health score, and pre- and postoperative SRS-22r survey pain scores. Univariate and multivariate general linear models were employed to identify factors associated with pain 2 years after AIS surgery. RESULTS: In multivariate analysis, patients with a lower preoperative pain score (i.e. higher pain) (P < 0.01) or higher postoperative T5-12 kyphotic angle (P = 0.02) had a worsened pain score 2 years after surgery. There were no remarkable differences for Lenke curve type, age, BMI, coronal radiographic parameters, lumbar disc degeneration, correction rate, number of fused vertebrae, or lowest instrumented vertebra. Higher preoperative Risser grade (P = 0.01) and lower preoperative SRS-22r mental health score (P < 0.01) were significantly related to a diminished preoperative SRS-22r pain score. CONCLUSION: While preoperative lumbar disc degeneration was not associated with pre- or postoperative pain in AIS, higher preoperative pain and higher postoperative T5-12 kyphotic angle had significant associations with augmented postoperative pain. Higher preoperative pain was related to increased Risser grade and lower mental health score. These slides can be retrieved under Electronic Supplementary Material.

Determination of optimal screw number based on correction angle for main thoracic curve in adolescent idiopathic scoliosis.

BACKGROUND: Reducing the number of screw insertions while maintaining good clinical outcomes can improve the efficiency and cost-effectiveness of scoliosis surgery. However, the optimal minimum number of pedicle screws remains unclear. This study searched for factors to estimate the fewest number of pedicle screws required between end vertebrae in relation to preoperative main thoracic curve flexibility. METHODS: Sixty-nine subjects (4 male and 65 female, mean age: 14.8 ± 2.5 years) who underwent skip pedicle screw fixation for Lenke type 1-4 or 6 curves and were followed for at least 1 year were enrolled. Intervention technique was selected according to the size and flexibility of the preoperative main thoracic curve. Surgery-related variables included pedicle screw number, rod material and diameter, and extent of Ponte osteotomy. The effect on postoperative correction angle (i.e., the difference between the preoperative supine position maximum bending and postoperative standing Cobb angles of the main thoracic curve) according to surgical intervention technique was estimated using multiple linear mixed regression models with the preoperative supine position maximum bending correction angle (i.e., the difference between the standing preoperative and supine position maximum bending Cobb angles) as a random effect. RESULTS: The preoperative maximum bending correction angle was 8-42° and had a moderate negative correlation with postoperative correction angle (r = -0.65, P < 0.01). Multivariate analysis revealed a 1.7° (95% CI 0.7-2.6; P < 0.01) correction gain per single-screw insertion and a 1.8° (95% CI 0.5-3.1; P < 0.01) gain per intervertebral level in Ponte osteotomy. CONCLUSIONS: The number of pedicle screws necessary to correct main thoracic adolescent idiopathic scoliosis curves can be estimated by calculating correction gains of 1.7° per pedicle screw and 1.8° per Ponte osteotomy intervertebral level. Based on these results, it may be possible to reduce invasiveness and cost for patients requiring a smaller degree of correction.

Spinal manifestations in 12 patients with musculocontractural Ehlers-Danlos syndrome caused by CHST14/D4ST1 deficiency (mcEDS-CHST14).

Musculocontractural Ehlers-Danlos syndrome caused by mutations in CHST14 (mcEDS-CHST14) is a recently delineated disorder, characterized by craniofacial, skeletal, visceral, and ocular malformations; and progressive cutaneous, skeletal, vascular, and visceral fragility-related manifestations. Spinal lesions, though one of the most serious complications, have not been investigated systematically. In this study, we report detailed and comprehensive information about spinal lesions of 12 patients with a mean age at the first visit of 13.4 years. Eight patients (66.7%) had scoliosis with a Cobb angle ≥10°, including one with severe scoliosis with a Cobb angle ≥45°. Five patients (41.7%) had kyphosis at the thoracolumbar junction with a kyphotic angle ≥20°. Three patients (25%) developed severe thoracolumbar kyphosis with a kyphotic angle ≥50° accompanied by thoracic lordosis with a wedge-like vertebral deformity and anterior vertebral osteophyte at the thoracolumbar junction, and two of them underwent surgical correction: complicated by fistula formation in one and performed safely and effectively through two-staged operation in the other. Six patients (50.0%) had cervical kyphosis, all of whom except one had kyphosis ≥20° at the thoracolumbar level. Two patients (16.7%) had atlantoaxial subluxation, and 10 patients (83.3%) had cervical vertebral malformations. Patients with mcEDS-CHST14 are susceptible to develop scoliosis, thoracolumbar kyphosis, and cervical kyphosis; and are recommended to have regular surveillance including total spine radiology. The present findings also suggest the critical role of dermatan sulfate in the development and maintenance of the spine.

Can surgery for adolescent idiopathic scoliosis of less than 50 degrees of main thoracic curve achieve good results?

BACKGROUND: It is generally recognized that the main thoracic curve Cobb angle threshold for surgical correction is approximately 50 degrees in patients with adolescent idiopathic scoliosis (AIS). Although AIS with a Cobb angle of <50 degrees is sometimes treated surgically to improve cosmesis, the precise outcomes are unclear. This study analyzed the postoperative results for AIS with a main thoracic curve of 50 degrees. METHODS: Thirty-nine consecutive patients with Lenke type 1-2 curves underwent posterior spinal fusion for AIS. These subjects were divided into the <50 degrees of main thoracic curve group (n = 14) and the ≥50 degrees group (n = 25). Clinical and radiographic data were compared. RESULTS: The mean Cobb angle of the main thoracic curve before and at 2 years after surgery for the <50 degrees and ≥50 degrees groups was 44.5 and 60.3 degrees (p < 0.001) and 14.0 and 19.5 degrees (p = 0.016), respectively. Preoperatively, both groups had comparable Scoliosis Research Society-22 (SRS-22) scores (all p > 0.05). Patients with a Cobb angle of <50 degrees displayed significantly milder postoperative pain (4.7 vs. 4.3, p = 0.031), with no remarkable differences in other SRS-22 domain scores. These patients also had a significantly shorter operative time (194 vs. 235 min, p = 0.021) and fused level (9.2 vs. 10.8 vertebrae, p = 0.006) along with similar correction rate (68.1 vs. 65.8%, p = 0.622) and blood loss volume (932 vs. 1009 ml, p = 0.715). CONCLUSIONS: Surgical correction of AIS with <50 degrees of main thoracic curve may less invasively achieve results that are comparable with those for AIS with 50 degrees or more, including improvements in self-image.

Mid-term results of computer-assisted skip pedicle screw fixation for patients with Lenke type 1 and 2 adolescent idiopathic scoliosis: A minimum five-year follow-up study.

PURPOSE: In skip pedicle screw fixation for adolescent idiopathic scoliosis (AIS), the mid-term effects of reducing screw number on correction and clinical results are uncertain. We clarified the mid-term outcomes of this technique in patients with Lenke type 1 and 2 AIS. METHODS: Thirty-four patients who underwent skip pedicle screw fixation (mean screw density: 1.35 screws) for Lenke type 1 and 2 AIS were retrospectively reviewed. The follow-up period was at least 5 years (mean follow-up period: 6.1 years), and the follow-up rate was 89.5%. Radiological parameters and clinical symptoms were evaluated before, immediately after, and at 2 years and 5 years after surgery. RESULTS: The mean Cobb angle of the main thoracic (MT) curve before, immediately after, at 2 years after surgery, and at the final 5-year minimum follow-up was 52.5°, 16.4°, 20.5°, and 19.4°, respectively. The Cobb angle of the MT curve was significantly improved immediately after, at 2 years after surgery, and at the final follow-up compared with that before surgery (p < 0.01). The mean correction rate immediately after surgery was 69.0% and the rate of correction loss at the final follow-up was 8.3%. All Scoliosis Research Society-22 patient questionnaire (SRS-22r) sub scores 5 years after surgery were significantly improved compared with those beforehand (p < 0.01). CONCLUSIONS: Correction using skip pedicle screw fixation in AIS was well maintained from the initial follow-up measurements to the final follow-up. The SRS-22r sub scores at the final follow-up were significantly improved over preoperative levels.