OBJECTIVE: To explore the trend of changes in the parameters of the spine-pelvic sagittal plane before and after surgery in patients with double-segment lumbar spondylolisthesis (LSL) and to evaluate the value of the surgical effect. METHODS: A retrospective analysis of 95 double-segment lumbar spondylolisthesis patients treated with posterior lumbar interbody fusion from October 2019 to October 2020 were analyzed, including 31 males and 64 females;age ranging from 41 to 63 years old, with an average of (52.10±4.35) years old;degree of lesion, 47 patients with gradeⅠand 48 patients with gradeⅡ. The surgical efficacy was evaluated according to the Oswestry dysfunction index(ODI) improvement rate at 3 months after operation. ODI improvement rate ≥50% was considered good, and <50% was considered bad. Ninety-five patients were divided into good curative effect group (74 cases) and poor curative effect group (21 cases) according to surgical curative effect. The clinical data, such as gender, age, body mass index, course of disease, degree of disease, operation time, intraoperative blood loss, and comorbidities were compared between two groups were compared. The parameters of spine pelvis sagittal plane were observed before and 3 months after operation, including spine sacral angle (SSA), T1 pelvic angle (TPA), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS). Clinical symptoms were evaluated using visual analogue scale (VAS) and ODI. The correlation between the changes of spine pelvis sagittal plane parameters and the changes of VAS and ODI before and after surgery were analyzed, and the value of spine pelvis sagittal plane parameters in evaluating the surgical efficacy of patients with double level lumbar spondylolisthesis at 3 months after surgery was evaluated. RESULTS: The courses of disease and surgical time in the group with poor efficacy were longer than those in the group with good efficacy, and the degree of lesion was higher in the group with poor efficacy (P<0.05). The SSA, TPA, LL, and SS of the group with good efficacy were higher than those of the group with poor efficacy before and 3 months after surgery, while the PT was lower than that of the group with poor efficacy (P<0.05). The changes in SSA, TPA, LL, PT, and SS before and after surgery in the group with good efficacy were greater than those in the group with poor efficacy (P<0.05). The VAS and ODI of both groups were lower at 3 months after surgery than before, and the group with good efficacy was lower(P<0.05). The changes in VAS and ODI before and after surgery in the group with good efficacy were greater than those in the group with poor efficacy (P<0.05). The changes in SSA, TPA, LL, PT, SS before and after surgery were positively correlated with the changes in VAS and ODI (P<0.05). Three months after surgery, SSA, TPA, LL, PT, and SS were used to evaluate the surgical efficacy of patients with dual level lumbar spondylolisthesis. The area under the curve (AUC) was 0.868, 0.797, 0.875, 0.822, and 0.853, respectively. The combined evaluation of all indicators resulted in the highest AUC, 0.927, and the best sensitivity and specificity were 90.50% and 91.89%, respectively. CONCLUSION The spine pelvis sagittal plane parameters SSA, TPA, LL, and SS of patients with double level lumbar spondylolisthesis before and after surgery show an upward trend;PT shows a downward trend;PI do not change significantly. And the changes of SSA, TPA, LL, SS, and PT are closely related to the patient's pain level and the improvement of lumbar function, which can be used as parameters to evaluate the surgical efficacy.
Female ; Animals ; Male ; Humans ; Adult ; Middle Aged ; Spondylolisthesis/surgery* ; Retrospective Studies ; Sacrum ; Blood Loss, Surgical ; Body Mass Index

OBJECTIVE: To evaluate the feasibility of S₂ alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters. METHODS: A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S₂ alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed. RESULTS: In all 83 children, 6.5 mm diameter S₂ iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage. CONCLUSION The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S₂ alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.
Humans ; Male ; Female ; Child ; Adolescent ; Child, Preschool ; Ilium/surgery* ; Retrospective Studies ; Feasibility Studies ; Bone Screws ; Pelvis ; Sacrum/surgery* ; Spinal Fusion/methods*

Objective: To investigate the clinical outcome and preventive effect of polyetheretherketone(PEEK) rod hybrid surgery on proximal junction failure(PJF) after long-segment fusion of adult spinal deformity. Methods: A retrospective study was conducted to analyze patients with degenerative scoliosis/kyphosis who underwent long-segment decompression and fusion surgery at Department of Orthopedics, Peking University First Hospital from January 2017 to December 2021. A total of 75 patients were included in the study, including 14 males and 61 females, aged (67.2±6.8)years (range:55 to 84 years). According to the operation method chosen by the patients, the patients were divided into PEEK rod hybrid group (20 cases) and traditional titanium rod group (55 cases). The general information of the patients was collected, and the coronal and sagittal parameters of the spine were measured before operation, at 1 month after operation, and at the last follow-up. The clinical effect of surgery was judged by the visual analogue scale (VAS) and Oswestry disability index (ODI). Whether proximal junctional kyphosis (PJK) and PJF occurred during the follow-up and the time of occurrence were recorded. Comparisons between groups were performed using independent sample t test, Mann-Whitney U test, χ² test and Fisher's exact probability method. The data before and after surgery in the same group were compared using the paired sample t test and the Wilcoxon test. Results: There were no significant differences in age, gender, body mass index, bone mineral density, distal instrumented vertebrae, surgical segments, osteotomy method, operation time, and intraoperative bleeding between the two groups (all P>0.05). The follow-up time of the PEEK rod group was shorter(M(IQR)16.5(4.8) vs. 25.0(12.0),Z=-4.230,P<0.01). There were no significant differences in coronal, sagittal parameters, VAS and ODI between the two groups before operation (all P>0.05). Postoperative coronal Cobb angle, pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis, sagittal vertical axis (SVA), VAS and ODI were significantly improved in both groups(all P<0.05). At the last follow-up, the SVA of the PEEK rod hybrid group was(3.74±2.40)cm, which was significantly lower than that of the titanium rod group (6.28±4.06)cm (t'=-3.318, P=0.002). At the last follow-up, the ODI of the PEEK rod hybrid group was 30.7±6.1, significantly better than the titanium rod group 39.3±17.2(t=-3.203, P=0.046). PJK occurred in 2 patients (10.0%) in the PEEK rod hybrid group, and no PJF phenomenon was observed. In the titanium rod group, 18 patients (32.7%) developed PJK, and 11 patients (20.0%) developed PJF. There was a statistically significant difference in the incidence of PJF between the PEEK rod hybrid group and the titanium rod group (P=0.031). Conclusions: PEEK rod hybrid surgery can achieve good clinical results in the treatment of adult spinal deformities. Compared with traditional titanium rod surgery, it can significantly reduce the incidence of postoperative PJF and improve the clinical function of patients.
Male ; Female ; Animals ; Humans ; Adult ; Retrospective Studies ; Titanium ; Kyphosis/etiology* ; Sacrum ; Osteotomy/adverse effects* ; Spinal Fusion/methods* ; Lumbar Vertebrae ; Treatment Outcome ; Postoperative Complications/epidemiology*

OBJECTIVE: To observe the efficacy and complications of one-stage tumor resection to treat primary sacral neurogenic tumors and to discuss some details in the clinically relevant anatomy. METHODS: A retrospective analysis of 26 patients with neurogenic turors of the sacral spine who were surgically treated from January 2001 to January 2018, including 16 males and 10 females, aged from 21 to 69 years old with an average age of (39.3±10.9) years old. The courses of diseases ranged from 3 to 56 months with an average of (17.9±10.1) months. The diameters of presacral components ranged from 3.3 to 19.6 cm with an average of (8.7±4.1) cm. The proximal margin of presacral lesions was above the L₅S₁ level in 6 cases, and lower than L₅S₁ in 20 cases. A posterior incision approach for one-stage complete resection of the tumor was used firstly, and an anterior approach was combined when necessary. Spinal-pelvic reconstruction with the modified Galveston technique was also carried out in relevant cases. Whether to preserve the tumor-involved nerve roots depended on the situation during the operation. The operation time, intraoperative blood loss, pain relief, and complications were recorded. The lumbosacral spine stability and sacral plexus neurological function were evaluated during postoperative follow-up, and local recurrence and distant metastasis were examined as well. RESULTS: Total excision was achieved in all 26 patients, with an operation time of (160.4±35.3) mins and an intraoperative blood loss of (1 092.3±568.8) ml. Tumors have been removed via a posterior-only approach in 21 cases and via combined anterior/posterior approaches in 5 cases. The diameter of presacral masses components ranged from 11.3 to 19.6 cm with an average of (15.1±3.2) cm in patients with combined anterior/posterior approaches, and ranged from 3.3 to 10.9 cm with an average of (7.2±2.4) cm in patients with a posterior-only approach. Five of the six patients whose proximal margin of presacral masses was above the L₅S₁ level adopted combined anterior/posterior approaches, and 20 patients lower than the L₅S₁ level adopted the posterior-only approach. All the patients were followed up for 6 to 82 months with an average of(45.4±18.2)months. Postoperative lumbosacral pain and lower extremity radicular pain were significantly relieved, and sensation, muscle strength and bowel and bladder function were also improved to varying degrees. The postoperative early complications included superficial wound infection in 1 case and cerebrospinal fluid leakage in 2 cases. Pathology confirmed 17 cases of schwannoma, 7 cases of neurofibroma and 2 cases of malignant schwannoma. Local recurrence was observed in two cases of benign neurogenic tumors. One patient with a malignant nerve sheath tumor had lung metastasis, who died 20 months after the operation. In 17 cases of upper sacral neurogenic tumors, 4 cases did not undergo spinal-pelvic reconstruction with internal fixation, of which 2 cases suffered from postoperative segmental instability. Tumor-involved nerve roots were resected during surgery in 7 cases. One of these patients who had S₂ and S₃ nerve roots sacrificed simultaneously had an impaired bladder and bowel function postoperatively, and did not recover completely. In the other 6 cases, the neurological function was not damaged obviously or recovered well. CONCLUSION The posterior approach can directly expose the lesions, and it is also convenient to deal with nerve roots and blood vessels. The operation time, intraoperative blood loss, degree of symptom relief, complication rate, and recurrence and metastasis rate can be controlled at an appropriate level. It is a safe and effective surgical approach. When the upper edge of the presacral mass is higher than the L₅S₁ level or the diameter of the presacral mass exceeds 10 cm, an additional anterior approach should be considered. The stress between the spine and pelvis is high, and internal fixation should be used to restore the mechanical continuity of the spine and pelvis during resection of neurogenic tumors of the high sacral spine. Most of the parent nerve roots have lost their function. Resection of a single parent nerve root is unlikely to cause severe neurological dysfunction, while the adjacent nerve roots have compensatory functions and should be preserved as much as possible during surgery.
Adult ; Aged ; Blood Loss, Surgical ; Female ; Humans ; Male ; Middle Aged ; Pain/pathology* ; Postoperative Complications/pathology* ; Retrospective Studies ; Sacrum/surgery* ; Treatment Outcome ; Young Adult

OBJECTIVE: To evaluate the efficacy of iliolumbar fixation in the treatment of U-shaped sacral fractures. METHODS: A retrospective study was conducted on the 14 complex U-shaped sacral fractures which had been treated from January 2014 to December 2019, involved 10 males and 4 females, aged 24 to 48 (35.4±6.5) years. Fracture healing time, nerve function, clinical function and complications were observed in the patients. RESULTS: All patients were followed up for 9 to 16(26.0±5.9) months. The complete weight-bearing time for bone healing was(12.4±2.0) weeks. One case of surgical incision infection occurred after operation, and one case of sacrum nailspenetrated to the outer plate of sacrum. No complications such as pressure ulcers, loosening or rupture of internal fixation occurred. According to Gibbons scoring, the neurological function recovered from preoperative 2.9±0.9 to postoperative 2.1±1.1, there were statistically significant differences between preoperative and postoperative ( CONCLUSION Sacral lumbar fixation is an effective method for the treatment of U-shaped sacrum fractures. It has the advantages of strong internal fixation and satisfactory functional recovery.
Bone Screws ; Female ; Fracture Fixation, Internal ; Humans ; Male ; Retrospective Studies ; Sacrum/surgery* ; Spinal Fractures/surgery* ; Treatment Outcome

PURPOSE: The prevalence of osteoporotic sacral fractures is increasing. Traditionally, conservative treatment is the 1st option, but it can increase the risk of comorbidity in the elderly. To reduce the complications and allow early mobility, iliosacral screw fixation with cement augmentation will be one of the treatment options for patients with osteoporotic sacral fractures. MATERIALS AND METHODS: This study reviewed 25 patients (30 cases) who had undergone percutaneous iliosacral screw fixation with cement augmentation for osteoporotic sacral fractures from July 2012 to December 2018 with a minimum follow up of six months. The clinical outcomes were assessed using the measures of pain (visual analogue scale [VAS] score), hospital stay and the date when weight-bearing started. All patients were evaluated radiologically for pull-out of screw, bone-union, and cement-leakage. RESULTS: Bone union was achieved in 30 cases (100%). The mean duration of the hospital stay was 24 days (4–66 days); weight-bearing was performed on an average nine days after surgery. The VAS scores immediately (3.16) and three months after surgery (2.63) were lower than that of the preoperative VAS score (8.3) (p<0.05). No cases of cement-leakage or neurologic symptoms were encountered. Two patients (6.7%) experienced a pulling-out of the screw, but bone-union was accomplished without any additional procedures. CONCLUSION: Percutaneous iliosacral fixation with cement augmentation will be an appropriate and safe surgical option for osteoporotic sacral fractures in the elderly in terms of early weight-bearing, pain reduction, and bone-union.
Aged ; Comorbidity ; Follow-Up Studies ; Humans ; Length of Stay ; Neurologic Manifestations ; Osteoporotic Fractures ; Prevalence ; Sacrum ; Weight-Bearing

OBJECTIVE: To analyze the displacement, stress and mechanism of lumbosacral joint disorder patients after bending and standing manipulation in the finite element model. METHODS: A three-dimensional finite element model of a patient with lumbosacral joint disorder was established. The finite element analysis method was used to observe and analyze the three loading conditions of the model:axial, 34 degree inclined upward and vertical upward. RESULTS: In the lumbosacral joint disorder model, the L₅ vertebral body was concentrated in the middle of the lower endplate, the intervertebral disc was concentrated in the center of the intervertebral disc, and the stress of S₁ and related structures were concentrated in the anterior and posterior edges of the vertebral body. After simulated manipulation, stress mainly concentrated in the anterior, posterior and central circular areas of L₅ vertebral upper endplate. The posterior structures of vertebral body concentrated in the ventral part of pedicle, isthmus and dorsal part of lamina. The stress of intervertebral disc dispersed in the posterior edge of vertebral body. Displacement results:In the lumbosacral joint disorder model, the left transverse process, the upper and lower articular process and the left part of spinous process were significantly displaced to the left, and the intervertebral disc was protruded forward. After simulated manipulation, the lower notch of L₅ vertebral body moved forward and upward; the area of intervertebral foramen increased; the inferior articular process of L₅ vertebral body moved forward; the superior articular process of sacrum moved forward and downward; the distance of articular process joints increased; and the displacement of sacrum concentrated on the posterior edge of vertebral body and the median sacral crest. CONCLUSIONS Successful lumbosacral joint modeling can be carried out by finite element analysis, and the mechanism of bending and erecting manipulation is clear, which is effective and safe for the treatment of lumbosacral joint disorders.
Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Intervertebral Disc ; Lumbar Vertebrae ; Lumbosacral Region ; Sacrum

Finite element method (FEM) was used to investigate the biomechanical properties of three types of surgical fixations of U-shaped sacral fractures. Based on a previously established and validated complete lumbar-pelvic model, three models of surgical fixations of U-shaped sacral fractures were established: ① S1S2 passed through screw (S1S2), ② L4-L5 pedicle screw + screw for wing of ilium (L4L5 + IS), and ③ L4-L5 pedicle screw + S1 passed through screw + screw for wing of ilium (L4L5 + S1 + IS). A 400 N force acting vertically downward, along with torque of 7.5 N·m in different directions (anterior flexion, posterior extension, axial rotation, and axial lateral bending), was exerted on the upper surface of L4. Comparisons were made on differences in separation of the fracture gap and maximum stress in sitting and standing positions among three fixation methods. This study showed that: for values of separation of the fracture gap produced by different operation groups in different positions, L4L5 + S1 + IS was far less than L4L5 + IS and S1S2. For internal fixators, the maximum stress value produced was: L4L5 + IS > L4L5 + S1 + IS > S1S2. For the intervertebral disc, the maximum stress value produced by S1S2 is much larger than that of L4L5 + S1 + IS and L4L5 + IS. In a comprehensive consideration, L4L5 + S1 + IS could be prioritized for fixation of U-shaped sacral fractures. The objective of this research is to compare the biomechanical differences of three different internal fixation methods for U-shaped sacral fractures, for the reference of clinical operation.
Biomechanical Phenomena ; Finite Element Analysis ; Fracture Fixation ; methods ; Humans ; Lumbar Vertebrae ; Pedicle Screws ; Sacrum ; injuries ; Spinal Fractures ; surgery ; Spinal Fusion

sacrum. Further dissection revealed the presence of an ectopic left side kidney. The ectopic kidney was lying inferior to the sigmoid colon and anterior to the bifurcation of left common iliac vessel. It was supplied by numerous aberrant vessels from the terminal part of abdominal aorta. One of the renal veins which drain the ectopic kidney was found to be persisting subcardinal vein and it is a novel finding. Such ectopic pelvic kidneys are susceptible to blunt trauma, iatrogenic injuries as well as pathologic manifestations.]]>
Abdomen ; Aorta, Abdominal ; Cadaver ; Colon, Sigmoid ; Deception ; Humans ; Kidney ; Male ; Pelvis ; Renal Veins ; Sacrum ; Veins

In this case report, we describe the use of ultrasound in the administration regional anesthesia for a super-super obese patient. A 23-year-old female patient (height 167.2 cm, weight 191.5 kg, body mass index 68.6 kg/m²) was admitted to the hospital for surgical repair of an anterior talofibular ligament rupture. We used ultrasound to help facilitate the administration of regional anesthesia. In the sagittal view of the lumbar spine, (with the patient in a sitting position) we were able to identify the border between the sacrum and the lumbar vertebral; in the transverse view, we were able to identify the transverse process, posterior dura, vertebral body, and the distance from the skin to the posterior dura. After skin marking, regional anesthesia was successfully performed. Based on this case study, we suggest that ultrasound can be very useful in regional anesthesia for severely obese patients.
Anesthesia ; Anesthesia, Conduction ; Body Mass Index ; Female ; Humans ; Ligaments ; Obesity ; Rupture ; Sacrum ; Skin ; Spine ; Ultrasonography ; Young Adult