[Efficacy of polyetheretherketone rod hybrid surgery in preventing proximal junctional failure after adult spinal deformity surgery].

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.

[Analysis of surgical strategy of percutaneous endoscopic lumbar discectomy in young and middle-aged double-segment patients with lumbar disc herniation].

OBJECTIVE: To investigate clinical efficacy and safety of single and double segmental percutaneous lumbar discectomy for young and middle-aged patients with double-segment disc herniation. METHODS: Retrospective analysis was undertaken for 32 young and middle-aged patients with percutaneous endoscopic lumbar discectomy (PELD) in the treatment of double-segment lumbar disc herniation from January 2015 to October 2018 in Peking University First Hospital. In the study, 18 cases were treated with single-segment treatment and 14 cases with double-segment treatment. Visual analogue score (VAS) and oswestry disability index (ODI) assessment were used to compare clinical symptom outcomes before surgery, 3 months after surgery and at the last follow-up. Macnab criteria were used to assess the patients' overall satisfaction after surgery. Imaging parameters included lumbar lordosis, intervertebral height at each segment and endplate angle of lesion segment on the X-ray. And Michigan State University(MSU) rating and Pfirrmann scoring system were used to evaluate the grade of disc herniation and disc degeneration respectively on magnetic resonance imaging (MRI). The perioperative parameters included the surgeon, anesthesia method, operation time, postoperative hospital stay, postoperative bracing time and perioperative complications. RESULTS: The mean follow-up time was (26.78±10.64) months. There was no significant difference in the follow-up time and baseline information between the two groups(P > 0.05). ODI scores 3 months post-operatively and at the last follow-up were lower in the double segment (P < 0.05). The ODI improvement was also more significant in the double-segment group at the last follow-up (P < 0.05). There was no significant difference in radiographic parameters at baseline (P>0.05). MSU scale for the primary segment was significantly lowered after both operations (P < 0.05). MSU scale for secondary segment was significantly lowered in double segment group but not in single segment group. Other imaging parameters were similar between the two groups (P > 0.05). The operation time of the single-segment group was significantly shorter than that of the double-segment group(P < 0.001). No perioperative complications were found in either group, but three patients underwent secondary lumbar surgery during the postoperative follow-up period in the single-segment group. CONCLUSION: For young and middle-aged patients with double-segment disc herniation, this study suggests double-segment PELD may be more advantageous than single-segment PELD in terms of asuring clinical efficacy without increasing perioperative risks.

[Clinical efficacy of short-term halo-pelvic traction combined with surgery in the treatment of severe spinal deformities].

OBJECTIVE: To evaluate the clinical efficacy of short-term halo-pelvic traction (HPT) combined with surgery in the treatment of severe spinal deformities. METHODS: In the study, 24 patients diagnosed as severe spinal deformity accepted the treatment of one-stage short-term HPT and two-stage surgery from January 2015 to May 2018 in our orthopedics department. 24 cases (9 males and 15 females) were retrospectively reviewed. The average age of the cohort was (28.8±10.0) years (12－48 years). The height, scoliosis angle, kyphosis angle, the height difference of shoulders, the height difference of crista iliaca, C7PL-CSVL and the perpendicular distance of S1 and the convex point of the patients were assessed at pre-traction, post-traction and post-surgery. The paired t test was used to analyze the difference among pre-traction, post-traction and post-surgery. RESULTS: The average traction time of 24 cases was (2.5±1.1) weeks (1－5 weeks). The height of pre-traction and post-traction were (141.7±11.2) cm (116-167 cm) and (154.1±9.5) cm (136－176 cm) respectively, showing significant difference (P < 0.05), and the increased height was (12.4±4.6) cm (4－20 cm). The average scoliosis angle before traction was 104.9°±35.0°(25°ï¼158°), and it was significantly decreased in post-traction[64.8°±21.0°(19°ï¼92°)] and post-surgery[39.3°±17.0° (10°-70°)] (P < 0.05). The traction's coronal correction rate was 37.2%±10.9% (11.9%－51.2%) and the total coronal correction rate was 61.9%±12.6%(26.9%-79.0%). The average kyphosis angle before traction was 106.9°±29.2°(54°ï¼163°), and it was significantly decreased in post-traction [63.1°±17.1°(32°ï¼92°)] and post-surgery [39.0°±16.8°(10°ï¼68°)](P < 0.05). The traction's sagittal correction rate was 40.0%±10.7%(16.7%－55.5%) and the total sagittal correction rate was 64.3%±10.7%(49.0%－87.5%). The average C7PL-CSVL before traction was (3.2±2.8) cm, and it was significantly decreased in post-traction [(2.5±2.5) cm] (P < 0.05). The perpendicular distance of S1 and the convex point before traction was (10.5±4.8) cm, and it was significantly decreased in post-traction[(8.4±3.5) cm] (P < 0.05). CONCLUSION: The one-stage short-term HPT combined with two-stage surgery is a safe and effective procedure for severe spinal deformities. The clinical efficacy is satisfactory and the complication is relatively less.

[Anterior cervical discectomy and fusion to treat cervical spondylosis with sympathetic symptoms].

OBJECTIVE: To investigate the clinical effectiveness of polytheretherketone (PEEK) cages assisted anterior cervical discetomy and fusion (ACDF) to treat cervical spondylosis with sympathetic symptoms. METHODS: Retrospective analysis was undertaken for 39 patients who were diagnosed as cervical spondylosis with sympathetic symptoms and underwent ACDF with PEEK cages. Radiographs obtained before surgery, after surgery, and at the final follow-up were assessed for quality of fusion. The following criteria were used for assessing radiographic success of fusion: (1) endplate obliterated with no lucent lines; (2) obliteration of disc space by bony trabeculae; (3) less than 2°of intervertebral motion or 2 mm of motion between the spinous processes at the operated segment on flexion-extension lateral radiographs. The sympathetic symptoms including vertigo, headache, tinnitus, nausea and vomiting, heart throb, hypomnesia and gastroenterological discomfort were scored by 20-point system preoperatively, 2 months postoperatively and at the final follow-up. The recovery rate and clinical satisfaction rate were also evaluated. Surgical complications were also assessed. RESULTS: They were followed up for at least one year. The mean follow-up was 15.6 months. Radiographs of the cervical spine at the last follow-up revealed a solid fusion with no signs of a pseudoarthrosis in 36 cases. In two patients delayed union and bony fusion were achieved at the end of 9 and 11 months. Pseudoarthosis was found in 1 case but the patient had no symptoms. The score of sympathetic symptoms before surgery, 2 months after surgery and at the final follow-up were 8.4±1.0,2.2±0.3,and 2.4±0.3, respectively. There were 22 excellent cases, 15 good cases, 1 fair case and 1 bad case in terms of RR. Good to excellent results were attained in 95% of theses patients. The sympathetic symptoms improved in all the patients and the score was significantly improved after surgery. There was one patient who had cerebral spinal fluid leakage but he recovered one week after surgery. Two patients felt a mild swallowing discomfort, but it disappeared within one month after surgery. Subcutaneous hematoma occurred in one patient due to obstructed drainage. It was cleared two days after surgery. CONCLUSION: Cervical spondylosis patients with sympathetic symptoms may be managed successfully with ACDF using PEEK cages. Successful clinical results regarding symptom improvement and general satisfaction with the surgical procedure depend not only on obtaining successful decompression and radiographic fusion but also on patient selection.

[Efficacy of transforaminal endoscopic nerve root decompression in the treatment of degenerative lumbar spinal stenosis].

OBJECTIVE: To evaluate the feasibility of transforaminal endoscopic nerve root decompression for degenerative lumbar spinal stenosis (DLSS). METHODS: From July 2011 to April 2016, 96 cases of single segment DLSS were involved. All the patients had unilateral lower extremity neurological symptoms, signs, neurogenic intermittent claudication of less than 500 m. Imaging examinations (CT or MRI) or diagnostic nerve root block confirmed single segment degeneration. The mean age was (71.6±5.4) years, male: 55 cases, female: 41 cases. Their intraoperative blood loss, operation time, complications, ambulation time and discharge time were recorded. Leg pain VAS, ODI were used to evaluate the pain and lumbar function of the patients. The clinical efficacy was evaluated by Nakai evaluation. RESULTS: All the patients were performed endoscopic decompression of the lateral recess and nerve root by removing the ventral part of the superior facet joint, the ligamentum flavum and the intervertebral disc. The decompression range was from the inferior edge of the upper pedicle to the superior edge of the lower pedicle. The nerve root was detected to have no compression and the pulse of nerve root returned to normal. The patient got ambulant on the operation day and discharged if he had no discomfort symptom. In the study, 68 cases got follow up. The mean follow-up time was 12.1 months (6-63 months). The VAS at different follow-up time points was improved relative to the baseline, and the difference was statistically significant (F=491.60, P<0.001). The ODI at different follow-up time points was improved relative to the baseline, and the difference was statistically significant (F=189.91, P<0.001). The excellent and good rates of Nakai evaluation were 79.4% (excellent in 42 cases, good in 12 cases, fair in 10 cases and poor in 4 cases). The mean intraoperative blood loss was (49.29±11.86) mL. The mean operation time was (92.46±21.34) min. The mean ambulation time was 1.8 h. The mean discharge time was 2.3 days. Postoperative epidural hematoma was found in 1 case. Foot drop was found in 1 case. Second stage open surgery was performed in 6 cases. CONCLUSION: We can apply transforaminal endoscopic decompression for the patients of lumbar spinal stenosis who have unilateral nerve root irritation. Patients with transforaminal endoscopic decompression can get less surgical trauma, quick recovery and obtain good short-term outcome.

[Polymethylmethacrylate augmentation of bone cement injectable cannulated pedicle screws was used to treat degenerative lumbar scoliosis with osteoporosis].

OBJECTIVE: To describe the application of polymethylmethacrylate (PMMA) augmentation of cement-injectable cannulated pedicle screws for the treatment of degenerative lumbar scoliosis with osteoporosis. METHODS: Retrospective cohort study was used to compare cement injectable cannulated pedicle screws (CICPs) group with PMMA augmentation and control group with traditional method in the correction surgery for Lenke-silva level III and level IV degenerative scoliosis cases with osteoporosis. Both groups were followed up for 1 year. The clinical results were assessed by visual analog scale (VAS) of pain on lumbar and lower limbers, Oswestry disability index (ODI) score and EuroQol-5 dimensions (EQ-5D) score. The coronal major curve Cobb angel in coronal plane and thoracic kyphosis Cobb angle, lumbar lordosis Cobb angle and sagittal vertical axis (SVA) in sagittal plane were tested in whole long spine X ray. The fusion rates were evaluated by lumbar X ray and dynamic X ray. RESULTS: In this study 34 cases were enrolled, 15 cases in CICPs group and 19 cases in control group. The general characteristics including age, gender, weight, height, BMI and BMD were without statistical difference between the two groups. There were (5.7±2.2)PMMA augmentation screws in CICPs group. The operation time, blood loss and blood transfusion were higher in CICPs group than in control group, but without statistical difference. Lumbar VAS, lower limbers VAS, ODI score and EQ-5D were all better in 1 month postoperation, 6 months postoperation and 1 year postoperation than in preoperation in both groups. lumbar VAS scores of CICPs group in 6 months postoperation (CICPs group 3.1±1.3 vs. control group 4.4±1.4, P<0.01) together with lumbar VAS scores (CICPs group 3.3±1.0 vs. control group 5.2±1.4, P<0.01), ODI scores (CICPs group 22.7±17.2 vs. control group 31.4±18.5, P<0.01) and EQ-5D in 1 year postoperation (CICPs group 2.9±2.0 vs. control group 3.5±2.5, P<0.01)were lower than those of control group. The coronal major curve Cobb angels were all lower in 1 month postoperation, 6 months postoperation and 1 year postoperation than in preoperation in both groups; thoracic kyphosis Cobb angle and lumbar lordosis Cobb angle were all higher in 1 month postoperation, 6 months postoperation and 1 year postoperation than in preoperation in both groups. The coronal major curve Cobb angel was lower in CICPs group than that in control group in 1 year postoperation (CICPs group 17.6°±6.9° vs. control group 21.2°±7.2°, P<0.01)and thoracic kyphosis Cobb angle was higher in CICPs group than that in control group in 6 months postoperation (CICPs group -33.5°±8.8 ° vs. control group -28.9°±8.3°, P<0.01) and 1 year postoperation (CICPs group -33.0°±8.1° vs. control group -26.3°±7.4°, P<0.01) together with lumbar lordosis Cobb angle were higher in CICPs group than that in control group in 1 year postoperation (CICPs group 26.4°±8.1° vs. control group 22.1°±7.3°, P<0.01). CONCLUSION: Polymethylmethacrylate augmentation of bone cement-injectable cannulated pedicle screws for the treatment of degenerative lumbar scoliosis with osteoporosis was effective and safe, the short-term clinical result was good.

[Clinical research of percutaneous vertebroplasty or percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures induced by glucocorticosteroid].

OBJECTIVE: To investigate the clinical characteristics of vertebral compression fracture (VCF) in glucocorticosteroid-induced osteoporosis (GIOP) and risk of vertebral refracture after percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). METHODS: In the study, 570 cases who received PVP or PKP as treatments of VCF from January 2010 to December 2013 were retrospective reviewed, of which 42 were GIOP and 21 were followed up as GIOP group, and the other 528 were primary osteoporosis and 391 were followed up, of which 84 were selected as Control group based on age and gender. The fracture location, ratio of single segment fracture and multiple segments fracture in the two groups were compared. In the final follow up, the reoperation rates for vertebral refractures by the Kaplan-Meier method in the two groups were compared. RESULTS: The follow up periods were (24.0± 13.1) months in GIOP group and (25.8±14.4) months in control group(P>0.05). In GIOP group, there were 11 cases with one-segment fracture, 2 with two-segments fracture, 3 with three-segments fracture, 2 with four-segments fracture, 2 with five-segments fracture and 1 with eight-segments fracture. In Control group, there were 67 cases with one-segment fracture, 12 with two-segments fracture, 3 with three-segment fracture, and 2 with four-segments fracture. The ratio of single segment fracture in GIOP group was significantly lower than that in Control group(52.4% vs. 79.8%,P=0.01). There were 50 fracture segments in GIOP group and 109 fracture segments in Control group. The ratios of fracture segments located in thoracic segments(T1-T10), thoracolumbar segments(T11-L1)and lumbar segments(L2-L5)were 18%, 46% and 36% in GIOP group and 11.9%, 58.7% and 29.4% in Control group (P>0.05). The refracture rate in GIOP group was higher than that in control group (23.8% vs. 6.0%). The survival rate was lower in GIOP group than that in control group (P<0.01). CONCLUSION: The predilection site of VCF was similar in GIOP and primary osteoporosis (thoracolumbar segments> thoracic segments> lumbar segments). The risk of multiple segments VCF was higher in GIOP than in primary osteoporosis. The risk of vertebral refractures after PVP or PKP was higher in GIOP than in primary osteoporosis.