[Construction and stability analysis of finite element model for spinal canal reconstruction with miniplates fixation].

OBJECTIVE: To establish the finite element model of spinal canal reconstruction and internal fixation,analysis influence of spinal canal reconstruction and internal fixation on spinal stability,and verify the effectiveness and reliability of spinal canal reconstruction and internal fixation in spinal canal surgery. METHODS: A 30-year-old male healthy volunteer with a height of 172 cm and weight of 75 kg was selected and his lumbar CT data were collected to establish a finite element model of normal lumbar L3-L5,and the results were compared with in vitro solid results and published finite element analysis results to verify the validity of the model. They were divided into normal group,laminectomy group and spinal canal reconstruction group according to different treatment methods. Under the same boundary fixation and physiological load conditions,six kinds of activities were performed,including forward bending,backward extension,left bending,right bending,left rotation and right rotation,and the changes of range of motion (ROM) of L3-L4,L4-L5 segments and overall maximum ROM of L3-L5 were analyzed under the six conditions. RESULTS: The ROM displacement range of each segment of the constructed L3-L5 finite element model was consistent with the in vitro solid results and previous literature data,which confirms the validity of the model. In L3-L4,ROM of spinal canal reconstruction group was slightly increased than that of normal group during posterior extension(>5% difference),and ROM of other conditions was similar to that of normal group(<5% difference). ROM in laminectomy group was significantly increase than that in normal group and spinal canal reconstruction group under the condition of flexion,extension,left and right rotation. In L4-L5,ROM in spinal canal reconstruction group was similar to that in normal group(<5% difference),while ROM in laminectomy group was significantly higher than that in normal group and spinal canal reconstruction group(>5% difference). In the overall maximum ROM of L3-L5,spinal canal reconstruction group was only slightly higher than normal group under the condition of posterior extension(>5% difference),while laminectomy was significantly higher than normal group and spinal canal reconstruction group under the condition of anterior flexion,posterior extension,left and right rotation(>5% difference). The changes of each segment ROM and overall ROM of L3-L5 showed laminectomy group>spinal canal reconstruction group>normal group. CONCLUSION: Laminectomy could seriously affect biomechanical stability of the spine,but application of spinal canal reconstruction and internal fixation could effectively reduce ROM displacement of the responsible segment of spine and maintain its biomechanical stability.

An innovative approach to assess spinal canal expansion following French-door cervical laminoplasty by intraoperative ultrasonography.

OBJECTIVE: To investigate the feasibility and effectiveness of applying intraoperative ultrasound (IOUS) to evaluate spinal canal expansion in patients undergoing French-door cervical laminoplasty (FDCL). MATERIALS AND METHODS: Twenty-five patients who underwent FDCL for multilevel degenerative cervical myelopathy were prospectively recruited. Formulae describing the relationship between laminoplasty opening angle (LOA) and laminoplasty opening size, the increase in sagittal canal diameter and the spinal canal area were deduced with trigonometric functions. The LOA was measured with IOUS imaging during surgery, and other spinal canal parameters were assessed. Actual spinal canal enlargement was verified on postoperative CT images. Linear correlation analysis and Bland‒Altman analysis were used to evaluate correlation and agreement between the intraoperative and postoperative measurements. RESULTS: The LOA at C5 measured with IOUS was 27.54 ± 3.12°, and it was 27.23 ± 3.02° on postoperative CT imaging. Linear correlation analysis revealed a significant correlation between IOUS and postoperative CT measurements (r = 0.88; p < 0.01). Bland-Altman plots showed good agreement between these two methods, with a mean difference of 0.30°. For other spinal canal expansion parameter measurements, correlation analysis showed a moderate to a high degree of correlation (p < 0.01), and Bland-Altman analysis indicated good agreement. CONCLUSION: In conclusion, during the French-door cervical laminoplasty procedure, application of IOUS can accurately evaluate spinal canal expansion. This innovative method may be helpful in improving surgical accuracy by enabling the operator to measure and determine canal enlargement during surgery, leading to ideal clinical outcomes and fewer postoperative complications. CLINICAL RELEVANCE STATEMENT: The use of intraoperative ultrasonography to assess spinal canal expansion following French-door cervical laminoplasty may improve outcomes for patients undergoing this procedure by providing more accurate measurements of spinal canal expansion. KEY POINTS: • Spinal canal expansion after French-door cervical laminoplasty substantially influences operative prognosis; insufficient or excessive lamina opening may result in unexpected outcomes. • Prediction of spinal canal expansion during surgery was previously impracticable, but based on this study, intraoperative ultrasonography offers an innovative approach and strongly agrees with postoperative CT measurement. • Since this is the first research to offer real-time canal expansion guidance for cervical laminoplasty, it may improve the accuracy of the operation and produce ideal clinical outcomes with fewer postoperative complications.

Is there a risk of further displacement of the fractured fragment into the spinal canal in osteoporotic vertebral burst fractures after unilateral PKP? A prospective study.

BACKGROUND CONTEXT: The optimal treatment for osteoporotic vertebral burst fracture (OVBF) without neurological symptoms is still a matter of debate. PURPOSE: To evaluate the safety and efficacy of percutaneous kyphoplasty (PKP) for OVBF. STUDY DESIGN: The study is a prospective study and is registered in the China Clinical Trials Registry with the registration number ChiCTR-OOC-17013227. PATIENT SAMPLE: The study involved 119 patients with 137 fractured vertebrae who underwent unilateral PKP for OVBF. OUTCOME MEASURES: The measurements were carried out independently by two physicians and measured with picture archiving and communication system (PACS) and ImageJ software (National Institutes of Health, Bethesda, MD, USA). METHODS: The change in the spinal canal area and posterior wall protrusions (PWP) were measured before and after surgery via three-dimensional computed tomographic imaging (CT). Preoperative, postoperative, and final follow-up standing X-rays were used to measure the height of the anterior wall (HAW), height of the posterior wall (HPW), and local kyphotic angle (LKA). Additionally, visual analogue scale (VAS) and the Oswestry Disability Index (ODI) were also determined. RESULTS: Among the 137 vertebrae assessed, 79 exhibited an increased postoperative canal area, while 57 showed a decrease, with mean values of 8.28±6.871 mm² and -9.04±5.991 mm², respectively. Notably, no significant change in postoperative canal area was identified on the entire dataset (p>.01). There was a significant decrease between median preoperative (3.9 [IQ1-IQ3=3.3-4.8] mm) and postoperative (3.7 [IQ1-IQ3=3.0-4.4] mm) PWP (p<.01). Preoperative and postoperative HAW measurements were 19.4±6.1 mm and 23.2±5.2 mm, respectively (p<.01). However, at the final follow-up, the HAW was lower than the postoperative value. The HPW was also significantly improved after surgery (p<.01), but at the final follow-up, it was significantly decreased compared with the postoperative measurement. Following surgery, KA was significantly corrected (p<.01); however, at the final follow-up, relapse was detected (average KA: 18.4±10.3°). At the final follow-up, both VAS and ODI were significantly improved compared with the preoperative period (p<.01). As for complications, 50 patients experienced cement leakage, and 16 patients experienced vertebral refracture. All patients did not develop neurological symptoms during the follow-up. CONCLUSIONS: OVBF without neurological deficits showed significant improvement in symptoms during the postoperative period after PKP. There was no notable alteration in the spinal canal area, but a significant decrease in PWP was observed. Consequently, we posit that PKP stands as a secure and efficacious surgical intervention for treating OVBF cases devoid of neurological symptoms.

Replantation of lamina spinous process ligament complex and miniature titanium plate shaping internal fixation in the treatment of tumors in the spinal canal.

OBJECTIVE: Purpose This study aims to explore the clinical efficacy of laminospinous process ligament complex reimplantation combined with mini-titanium plate fixation in the treatment of thoracolumbar intraspinal tumors. METHODS: A retrospective analysis was performed on 43 cases of intraspinal tumors treated with thoracolumbar intraspinal tumor resection from August 2018 to March 2021, and 27 cases underwent laminospinous process ligament complex reimplantation combined with micro titanium plate shaping. Fixation (laminar replantation group), and 16 patients underwent laminectomy combined with pedicle screw internal fixation (laminectomy group). The operation time, blood loss, drainage tube removal time, cerebrospinal fluid leakage, spinal instability, and the incidence of secondary spinal stenosis were compared between the two groups. The pain VAS score, ODI score, and modified Macnab at the last follow-up were compared between the two groups. And the laminar fusion rate of the laminoplasty group was measured. RESULTS: Both groups successfully completed the surgery and obtained complete follow-up. The incidence of cerebrospinal fluid leakage and secondary spinal canal stenosis in the laminectomy group was lower than that in the laminectomy group, and the difference was statistically significant (P < 0.05). There was no statistically significant difference in the incidence of spinal instability between the two groups (P > 0.05). The operation time and intraoperative blood loss in the laminectomy group were less than those in the laminectomy group, and the drainage tube removal time was earlier than that in the laminectomy group. The difference was statistically significant (P < 0.05). At the final follow-up, there was no statistically significant difference in the pain VAS score, ODI score, and modified Macnab between the two groups (P > 0.05), but they were all significantly improved compared with preoperative ones. Fusion evaluation was conducted on the laminoplasty group. Two years after surgery, the fusion rate was 97.56% (40/41). CONCLUSIONS: The application of laminospinous process ligament complex reimplantation combined with mini titanium plate fixation during thoracolumbar intraspinal tumor resection can effectively reconstruct the spinal canal and posterior column structure, reduce the incidence of cerebrospinal fluid leakage and secondary spinal stenosis. The laminar fusion rate is high.

[Unilateral interlaminar approach 270° circular spinal canal decompression under the iLESSYS Delta for the treatment of lumbar spinal stenosis in the elderly].

OBJECTIVE: To investigate the clinical effect of unilateral interlaminar approach 270° circular spinal canal decompression under the Interlaminar Endoscopic Surgical System(iLESSYS) Delta for the treatment of lumbar spinal stenosis (LSS) in the elderly. METHODS: Total of 29 patients with LSS treated with the iLESSYS Delta from December 2018 to January 2021 were retrospectively analyzed, including 12 males and 17 females with an average age of (71.52±10.82) years old ranging from 63 to 83 years old. All patients had definite intermittent claudication, mainly neurogenic symptoms of both lower limbs. All patients had single-level spinal stenosis, including L3,4 5 cases, L4,5 21 cases, and L5S1 3 cases. Visual analogue scale (VAS), Oswestry Disability Index (ODI) and modified Macnab assessment criteria were used to evaluate pain, low back pain dysfunction index and clinical efficacy, respectively. RESULTS: All 29 cases were successfully completed. The operation time was (73.45±5.89) min, the intraoperative blood loss was (9.93±0.83) ml, the hospital stay was (4.03±0.41) days, and the follow-up was more than 12 months. The VAS scores of low back pain before surgery and 1 day, 1 month, 3 months, 1 year after surgery were 2.31±0.88, 1.45±0.62, 1.21±0.61, 1.10±0.55, 1.03±0.49;VAS of leg pain were 6.48±0.49 0.56, 1.97±0.61, 1.31±0.59, 1.17±0.59, 1.10±0.55;ODI scores were 38.41±2.74, 18.14±1.17, 5.17±0.53, 5.07±0.45, 4.90±0.48;low back and leg pain VAS score and ODI score have statistically significant differences between preoperative and postoperative follow-up time points (P<0.05). The MacNab efficacy evaluation at 1-year follow-up:excellent in 22 cases, good in 5 cases and fair in 2 cases. CONCLUSION: The clinical effect of unilateral interlaminar approach 270° circular spinal canal decompression under the iLESSYS Delta for the treatment of lumbar spinal stenosis in the elderly is satisfactory, with the advantages of less trauma and less bleeding, large microscopic operation space, sufficient decompression, and ideal post-operative recovery, and at the same time, it can minimize the damage to the stable structure of the lumbar spine, which is an ideal surgical method for the treatment of elderly lumbar spinal stenosis.

Efficacy of OLIF combined with pedicle screw internal fixation for lumbar spinal stenosis on spinal canal changes before and after surgery.

PURPOSE: The purpose of the study was to evaluate the efficacy of OLIF combined with pedicle screw internal fixation in the treatment of lumbar spinal stenosis by assessing the changes in spinal canal before and after surgery. METHODS: In this retrospective study, we included sixteen patients who underwent a combination of single-segment OLIF and pedicle screw internal fixation for the treatment of lumbar spinal stenosis at the Affiliated Hospital of Jiangxi University of Chinese Medicine between February 2018 and August 2022. The patients' pre- and post-operative data were compared. Intraoperative bleeding, duration of surgery, visual analogue score (VAS), Oswestry Disability Index (ODI), disc height (DH), cross-sectional area of vertebral canal (CSAVC), cross-sectional area of dural sac (CSADS), cross-sectional area of intervertebral foramen (CSAIF), spinal canal volume (SCV), spinal canal volume expansion rate, lumbar lordosis, and sagittal vertical axis were observed and recorded. The efficacy of OLIF combined with pedicle screw internal fixation for lumbar spinal stenosis on spinal canal changes before and after surgery was summarized. RESULTS: The results showed that OLIF combined with pedicle screw internal fixation effectively restored disc height and increased the cross-sectional area of the spinal canal. It also had an indirect decompression effect. The intraoperative bleeding and duration of surgery were within acceptable ranges. The VAS and ODI scores significantly improved after surgery, indicating a reduction in pain and improvement in functional disability. The CSAVC, CSADS, CSAIF, SCV, and spinal canal volume expansion rate were all increased postoperatively. Additionally, there was improvement in lumbar lordosis and sagittal vertical axis. We conducted a follow-up of all patients at 1 year after the surgery. The results revealed that the parameter values at 1 year post-surgery showed varying degrees of decrease or increase compared to the immediate postoperative values. However, these values remained statistically significant when compared to the preoperative parameter values (P < 0.05). CONCLUSIONS: OLIF combined with pedicle screw internal fixation effectively restores disc height and increases the cross-sectional area of the vertebral canal in patients with LSS, reflecting the indirect decompression effect. Measuring parameters such as DH, CSAVC, CSADS, CSAIF, SCV, and SCV expansion rate before and after surgery provides valuable information for evaluating the efficacy and functional recovery of the lumbar spine in LSS patients treated with OLIF surgery.

Lipoblastomatosis Extended into the Lumbar Spinal Canal in a Child: A Case Report.

INTRODUCTION: Lipoblastoma and lipoblastomatosis are rare benign mesenchymal adipose tumors that originate from embryonic white adipocytes and occur most commonly in infancy and early childhood. Lipoblastomas occur in the extremities and trunk, including the retroperitoneum and peritoneal cavity. Therefore, infiltration into the spinal canal has rarely been reported. CASE PRESENTATION: A 4-year-old girl presented to our clinic because of difficulty sitting on the floor with her legs straight. She also complained of enuresis and constipation for the past 6 months with persistent headaches and back pain evoked by body anteflexion. A magnetic resonance imaging revealed a massive lesion of the psoas major muscle, retroperitoneal, and subcutaneous spaces, extending into the spinal epidural space between L2 and S1. The patient underwent surgery which resulted in gross total removal of the tumor from the spinal canal. The mass was yellowish, soft, lobulated, fatty, and easily removed from the surrounding structures. Pathology confirmed the diagnosis of lipoblastoma. The postoperative course was uneventful, and the patient was discharged without any signs of neurological deficit. CONCLUSION: We herein discuss a rare case of lipoblastoma extending into the spinal canal, resulting in neurological symptoms. Although this tumor is benign with no potential for metastasis, it is prone to local recurrence. Therefore, close postoperative observation should be performed.

Effect of the preoperative assessment of the anteroposterior diameters of the spinal canal and dural area on the efficacy of oblique lumbar interbody fusion in patients with lumbar spinal stenosis.

OBJECTIVE: The purpose of this study was to quantify the degree of lumbar spinal stenosis by assessing the anterior and posterior vertebral canal diameter and dural area, determine the sensitivity of the anterior and posterior spinal canal diameter, dural area and dural occupying rate in predicting the postoperative efficacy of oblique lumbar interbody fusion (OLIF) for patients with single-stage lumbar spinal stenosis, and identify the corresponding indicators suggesting that OLIF surgery should not be performed. METHODS: In a retrospective analysis of patients who had previously undergone OLIF surgery in our hospital, we included a total of 104 patients with lumbar spinal stenosis who had previously undergone single-stage surgery in our hospital. Three independent observers were employed to measure the anterior and posterior diameter of the spinal canal (AD, mm), dural area (CSA, mm2), the spinal canal area (SCA, mm2), and the ratio of the dural area to the spinal canal area (DM, %) at the disc level with the most severe stenosis on MRI. According to the values of AD and CSA in preoperative MRI, patients were divided into three groups: A, B, and C (Group A: AD > 12 and 100 < CSA ≤ 130, group B: Except A and C, group C: AD ≤ 10 and CSA ≤ 75). Preoperative and postoperative clinical outcome scores (Japanese Orthopaedic Association [JOA] score, VAS score, modified Macnab standard) of 104 patients were statistically. RESULTS: There were significant differences in the preoperative and postoperative clinical correlation scores among the mild, moderate and severe lumbar spinal stenosis groups. The improvement rate of the post treatment JOA score, the difference between the preoperative and postoperative VAS score, and the modified Macnab standard were compared pairwise. There was no statistical significance in the improvement rate of the post treatment JOA score, the difference between the preoperative and postoperative VAS score, and the modified Macnab standard between Group A and Group B (P = 0.125, P = 0.620, P = 0.803). There were statistically significant differences between Group A and Group C and between Group B and Group C in the improvement rate of the JOA score, the difference in the pre- and postoperative VAS score, and the modified Macnab standard. The anterior and posterior vertebral canal diameter and dural area are sensitive predictors of the postoperative efficacy of OLIF surgery for single-stage lumbar spinal stenosis. Moreover, when the anterior and posterior vertebral canal diameter was less than 6.545 mm and the dural area was less than 34.43 mm2, the postoperative effect of OLIF surgery was poor. CONCLUSIONS: All the patients with mild, moderate, and severe lumbar spinal stenosis achieved curative effects after OLIF surgery. Patients with mild and moderate lumbar spinal stenosis had better curative effects, and there was no significant difference between them, while patients with severe lumbar spinal stenosis had poor curative effects. Both the anteroposterior diameter of the spinal canal and the dural area of the spinal canal were sensitive in predicting the curative effect of OLIF surgery for single-stage lumbar spinal stenosis. When the anterior and posterior vertebral canal diameter was less than 6.545 mm and the dural area was less than 34.43 mm2, the postoperative effect of OLIF surgery was poor.

An unusual case of pediatric cervical myelopathy due to congenital spinal canal stenosis.

Cervical myelopathy is a condition that is rarely reported in pediatric patients who have movement or neuromuscular disorders. We, herein, present a rare case of cervical myelopathy observed in a 14-year-old patient, who was previously a healthy boy treated with cervical laminoplasty, which was caused by cervical spinal canal stenosis based on multiple level disc herniation. The patient presented to the clinic with spastic and ataxic gait with previous diagnostic challenges. Magnetic resonance imaging showed cervical degenerative changes mainly marked at the C3-C4 and C4-C5 levels, along with canal narrowing and a central high signal cord abnormality on T2-weighted images. A C3-C4 open-door laminoplasty surgery technique was performed. The neurological symptoms and signs improved dramatically following surgery. Subsequently, cervical computed tomography and magnetic resonance imaging showed good decompression of the cervical spinal cord during the 5 years of follow-up with the preservation of the range of movement. We concluded that though it is pretty rare, cervical myelopathy should be considered in diagnosing adolescent patients with gait and balance disorders.

Balancing ability of patients with lumbar spinal canal stenosis.

PURPOSE: To determine the relationship between postural sway and the severity of lumbar spinal canal stenosis as well as the effect on postoperative improvement. METHODS: Stabilometry was performed before and 6 months after surgery in 52 patients (29 men and 23 women; mean age, 74.1 ± 7.8 years) who underwent decompression surgery for lumbar spinal canal stenosis. The environmental area (EA; the area surrounding the circumference of the stabilogram) and locus length per EA (L/EA) were evaluated. The patients were divided into moderate (n = 22) and severe (n = 30) groups according to the severity of canal stenosis. Patient characteristics and parameters were compared between the groups before and after surgery, including the visual analog scale (VAS) score for leg pain, Oswestry Disability Index (ODI), EA, and L/EA. In addition, factors affecting EA and L/EA were evaluated using multiple regression analysis. RESULTS: Age (p = 0.031), preoperative EA (p < 0.001), preoperative L/EA (p = 0.032), and sagittal vertical axis (p = 0.033) were significantly different between groups. The VAS score and ODI significantly improved postoperatively in both groups (p < 0.001). The EA significantly improved postoperatively only in the severe group (p < 0.001), whereas the L/EA did not significantly improve in either group. Multiple regression analysis showed that only the severity of canal stenosis was significantly associated with preoperative EA (p = 0.030), whereas age (p = 0.040) and severity of canal stenosis (p = 0.030) were significantly associated with preoperative L/EA. Diabetes was significantly associated with postoperative EA (p = 0.046) and L/EA (p = 0.030). CONCLUSION: The severity of canal stenosis affected abnormal postural sway, which improved after decompression surgery.

10-year Longitudinal MRI Study of Intervertebral Disk Degeneration in Patients With Lumbar Spinal Canal Stenosis After Posterior Lumbar Decompression Surgery.

STUDY DESIGN: A prospective longitudinal magnetic resonance imaging (MRI) study. OBJECTIVE: The objective of this study was to describe the progression of intervertebral disk (IVD) degeneration in patients who underwent posterior decompression surgery for lumbar spinal canal stenosis (LSS). SUMMARY OF BACKGROUND DATA: IVD degeneration contributes to the pathogenesis of LSS; however, the long-term consequences of degenerative changes after decompression surgery remain unknown. MATERIALS AND METHODS: Of 258 consecutive patients who underwent posterior lumbar decompression surgery for LSS, 62 who underwent MRI at their 10-year follow-up were included; 17 age-matched asymptomatic volunteers were analyzed as controls. Three MRI findings representing IVD degeneration were graded on their severity: decrease in signal intensity, posterior disk protrusion (PDP), and disk space narrowing (DSN). Clinical outcome was assessed using the low back pain (LBP) score from the Japanese Orthopaedic Association scoring system. We examined the association between the progression of degenerative changes on MRI and LBP/associated factors using logistic regression adjusting for age at baseline and sex. RESULTS: The severity of IVD degeneration tended to be higher in patients with LSS than asymptomatic volunteers at both baseline and follow-up. IVD degeneration progressed in all patients during the 10-year follow-up period. Progression of decrease in signal intensity and PDP was observed at L1/2 in 73% and at L2/3 in 34%, respectively (the highest frequencies in the lumbar spine). Progression of DSN was highest at L4/5 in 42%. The rates of PDP and DSN progression during the 10-year follow-up period tended to be greater in patients with LSS than in asymptomatic volunteers. No significant difference in the proportion of LBP deterioration was evident for individuals with and without MRI findings of progression. CONCLUSIONS: Our study reveals a natural history of the long-term postoperative course of IVD degeneration after posterior decompression surgery for LSS. Compared with healthy controls, patients with LSS seemed to be predisposed to IVD degeneration. Lumbar decompression surgery may promote the progression of DSN; however, progression of IVD degeneration after lumbar decompression surgery was not associated with worsening LBP scores.

Efficacy of surgical treatment on polypharmacy of elderly patients with lumbar spinal canal stenosis: retrospective exploratory research.

BACKGROUND: Polypharmacy is a growing public health problem occurring in all healthcare settings worldwide. Elderly patients with lumbar spinal canal stenosis (LSS) who manifest low back and neuropathic pain and have a high frequency of comorbidity are predicted to take many drugs. However, no studies have reported polypharmacy in elderly patients with LSS. Thus, we aimed to review the polypharmacy among elderly LSS patients with elective surgeries and examine how the surgical treatment reduces the polypharmacy. METHODS: We retrospectively enrolled all the patients aged ≥ 65 years who underwent spinal surgery for LSS between April 2020 and March 2021. The prescribed drugs of participants were directly checked by pharmacists in the outpatient department preoperatively and 6-month and 1-year postoperatively. The baseline characteristics were collected beside the patient-based outcomes including Roland-Morris Disability Questionnaire, Zurich Claudication Questionnaire, and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). The cutoff number of drugs for polypharmacy was defined as 6. The prescription drugs were divided into 9 categories: drugs for neuropsychiatric, cardiovascular, respiratory, digestive, endocrine metabolic, and urinary renal diseases; blood products; pain relief medication; and others. RESULTS: A total of 102 cases were finally analyzed, with a follow-up rate of 78.0%. Of the participants, the preoperative polypharmacy prevalence was 66.7%. The number of drugs 6-month and 1-year postoperatively was significantly less than the preoperative one. The proportions of polypharmacy at 6 months and 1 year after surgery significantly decreased to 57.8% and 55.9%, respectively. When the prescribed drugs were divided into 9 categories, the number of drugs for pain relief and digestive diseases was significantly reduced after surgery. The multi-variable analysis revealed that a higher score in the psychological disorder of JOABPEQ was associated with 3 or more drugs decreased 1-year postoperatively (OR, 2.5; 95% CI: 1.0-6.1). CONCLUSION: Polypharmacy prevalence was high among elderly LSS patients indicated for lumbar spinal surgery. Additionally, our data showed that lumbar spinal surgery was effective in reducing polypharmacy among elderly LSS patients. Finally, the multi-variable analysis indicated that better psychological condition was associated with the reduction of prescribed drugs after lumbar spinal surgery.

Technical note-in situ laminotomy: preserving posterior tension band in surgery of pediatric multilevel spinal tumor.

BACKGROUND: Laminotomy has been introduced in surgical practice to reduce complications of laminectomy after surgery of tumors in the spinal canal. However, the posterior ligament complex, which is routinely interrupted to remove the laminoplasty segment and gain access to the spinal canal, has a tendency not to heal and can lead to progressive kyphosis and collapse. CASE PRESENTATION: A 5-month-old boy affected by a thoracolumbar extradural tumor extending along seven spinal levels was operated on. The tumor was exposed and completely resected by a one-piece laminotomy with preservation of the integrity of the posterior tension band at both extremities. After 1-year radiological examination ruled out spinal deformity. CONCLUSION: The technique herein presented, which we named in situ laminotomy, allows to fully preserve the posterior tension band without reducing the exposure of the spinal canal in multilevel tumors. Additionally, the technique makes also the reconstruction of the spine elements very easy and rapid. However, longer follow-up is necessary to prove the effectiveness of this procedure in preventing long-term deformity and instability.

"Inside Disc Out" Discectomy for the Treatment of Discogenic Lumbar Spinal Canal Stenosis under the Intervertebral Foramen Endoscope.

OBJECTIVE: Conventional posterior-approach decompression surgeries have a higher risk of nerve root injury and dura laceration. We explore the therapeutic strategy and effect of "inside disc out" discectomy under intervertebral foramen endoscope technique for discogenic lumbar spinal canal stenosis (DLSS) treatment. METHODS: Twenty-nine patients with DLSS in the responsible segment were treated with "inside disc out" discectomy under intervertebral foramen endoscope technique between October 2017 to October 2019. Lower limb and back pain were recorded before operation, and visual analogue scale (VAS) score and Oswestry disability index (ODI) were recorded for lower limb and back pain at 1, 3, 6, and 12 months postoperatively. The postoperative effects were evaluated using the modified MacNab method for all the patients. RESULTS: All 29 patients successfully completed the operation. The operation time was 75-120 min, with an average of 90 ± 17 min. Postoperative lumbar CT examinations of all the patients showed full decompression of the spinal cord with no residual pressure. The average follow-up time for all the patients was 13 ± 3.5 months (12-18 months). The VAS score for lower back and lower limb pain was 7.52 ± 1.25 before the operation, and 1.80 ± 0.63, 1.33 ± 0.88, 1.07 ± 0.89, and 0.81 ± 0.51 at 1, 3, 6, and 12 months after the surgery, respectively. The Oswestry dysfunction index was 59.43 ± 10.04 before surgery and 29.67 ± 10.35, 21.13 ± 9.32, 14.52 ± 5.98, and 9.84 ± 4.68 at 1, 3, 6, and 12 months after the surgery, respectively. The VAS score and ODI index of low back and lower limb pain at different time points after the surgery were significantly improved compared to those before the surgery (P < 0.01). The effect of the modified MacNab was excellent in 26 patients, good in two patients, and fair in one patient. The excellent and good rates were 91.4%. Among them, one patient had symptoms of hyperesthesia in the anterior aspect of the thigh and decreased quadriceps muscle strength after lumbar 4/5 segment endoscopic surgery. After symptomatic and conservative treatment, the symptoms disappeared 4 weeks postoperatively, and there were no other serious surgical complications. CONCLUSIONS: Following the "inside disc out" discectomy under intervertebral foramen endoscope protocols, the risk of nerve injury can greatly be reduced, with good postoperative efficacy. Overall, the procedure is safe and feasible for DLSS treatment.

Mid thoracic intra-spinal facet cyst with lumbar canal stenosis: a rare 'double crush'.

INTRODUCTION: Intraspinal synovial cysts occurrence causing spinal canal occlusion are mostly seen in mobile segments of the spine (lumbar and cervical). An appearance of the cyst in thoracic spine is a relatively rare occurrence. We present an interesting case of 'double crush' caused by Lumbar canal stenosis with a mid-dorsal Facet cyst. CASE PRESENTATION: A 67-year-old woman presented with complaints of back pain with neurogenic claudication with significant loss of touch sensation and motor power of MRC grade 3/5 in lower extremities bilaterally. However, patient was hyperreflexic with Babinski sign positive. She was unable to perform tandem walking test and complained of instability. MRI of lumbar spine revealed lumbar canal stenosis. However, in view of the UMN signs, an MRI of the dorsal spine was done. It revealed an extradural, well-delineated lesion along the dorsal aspect of spine at T6-7 level. Thus the patient had a 'double crush' due to the FC along with lumbar canal stenosis. CLINICAL FINDINGS CORRELATED WITH THE IMAGING: Two teams simultaneously operated the 2 pathologies and T6-7 laminectomy along with left sided TLIF at L4-5 level was performed. Presently she is asymptomatic for back pain, claudication distance has improved to 800 m. CONCLUSION: Our case reiterates the importance of thorough clinical examination to avoid missing a diagnosis. Our case is the first in literature to report a 'double crush' due to a proximal dorsal FC and distal LCS. Both the pathologies were tackled in a single setting by two operating teams with a good functional outcome.

Spinal canal stenosis in children with achondroplasia: the role of augmentation laminoplasty-a 15-year single institution experience.

PURPOSE: Achondroplasia typically results in compressive spinal canal stenosis in one-third of children, but rare under the age of 15 years. Laminectomy is the mainstay of treatment but this leads to instability and progressive deformity requiring complex fixation. In order to reduce that risk, we developed a novel modified augmented laminoplasty that increases spinal canal diameter while preserving the posterior column stability. METHODS: All laminoplasty cases for spinal compressive achondroplasia from 2006 to 2020 were included. Ten augmentation laminoplasty procedures were performed in 7 children with regular clinical and radiological post-operative follow-up. Kyphotic deformity and clinical outcomes (neurological and urological) were evaluated. RESULTS: At presentation, clinical features included radiculopathy, neurogenic claudication or acute cauda equina compression with sphincter dysfunction. The average age at initial surgery was 11.2 (range 5-16) with a mean follow-up of 5 (range 2-8) years. All patients demonstrated improvement in neurogenic claudication symptoms after surgery; however, bladder dysfunction persisted in some children. In one child, cervical and lumbar augmentation laminoplasties were performed for concomitant disease. Augmentation laminoplasty effectively prevented deformity progression over time in all cases except one where a further revision laminoplasty with extension was required for screw loosening. Despite this, progressive symptomatic kyphotic deformity led to a 360° fixation. Minor complications included one dural breach (repaired intraoperatively) and one superficial wound infection. CONCLUSION: Augmentation laminoplasty is a viable surgical option following laminectomy in achondroplasia patients as an alternative to surgical fixation. Fixation can be reserved for cases where there is progressive deformity and kyphosis.