Analysis of the causes of cage subsidence after oblique lateral lumbar interbody fusion / 中国骨伤

OBJECTIVE@#To observe the cage subsidence after oblique lateral interbody fusion (OLIF) for lumbar spondylosis, summarize the characteristics of the cage subsidence, analyze causes, and propose preventive measures.@*METHODS@#The data of 144 patients of lumbar spine lesions admitted to our hospital from October 2015 to December 2018 were retrospectively analyzed. There were 43 males and 101 females, and the age ranged from 20 to 81 years old, with an average of (60.90±10.06) years old. Disease types:17 patients of lumbar intervertebral disc degenerative disease, 12 patients of giant lumbar disc herniation, 5 patients of discogenic low back pain, 33 patients of lumbar spinal stenosis, 26 patients of lumbar degenerative spondylolisthesis, 28 patients of lumbar spondylolisthesis with spondylolisthesis, 11 patients of adjacent vertebral disease after lumbar internal fixation, 7 patients of primary spondylitis in the inflammatory outcome stage, and 5 patients of lumbar degenerative scoliosis. Preoperative dual-energy X-ray bone mineral density examination showed 57 patients of osteopenia or osteoporosis, and 87 patients of normal bone density. The number of fusion segments:124 patients of single-segment, 11 patients of two-segment, 8 patients of three-segment, four-segment 1 patient. There were 40 patients treated by stand-alone OLIF, and 104 patients by OLIF combined with posterior pedicle screw. Observed the occurrence of fusion cage settlement after operation, conducted monofactor analysis on possible risk factors, and observed the influence of fusion cage settlement on clinical results.@*RESULTS@#All operations were successfully completed, the median operation time was 99 min, and the median intraoperative blood loss was 106 ml. Intraoperative endplate injury occurred in 30 patients and vertebral fracture occurred in 5 patients. The mean follow-up was (14.57±7.14) months from 6 to 30 months. During the follow-up, except for the patients of primary lumbar interstitial inflammation and some patients of lumbar spondylolisthesis with spondylolisthesis, the others all had different degrees of cage subsidence. Cage subsidence classification:119 patients were normal subsidence, and 25 patients were abnormal subsidence (23 patients were gradeⅠ, and 2 patients were gradeⅡ). There was no loosening or rupture of the pedicle screw system. The height of the intervertebral space recovered from the preoperative average (9.48±1.84) mm to the postoperative average (12.65±2.03) mm, and the average (10.51±1.81) mm at the last follow-up. There were statistical differences between postoperative and preoperative, and between the last follow-up and postoperative. The interbody fusion rate was 94.4%. The low back pain VAS decreased from the preoperative average (6.55±2.2 9) to the last follow-up (1.40±0.82), and there was statistically significant different. The leg pain VAS decreased from the preoperative average (4.72±1.49) to the final follow-up (0.60±0.03), and the difference was statistically significant (t=9.13, P<0.000 1). The ODI index recovered from the preoperative average (38.50±6.98)% to the latest follow-up (11.30±3.27)%, and there was statistically significant different. The complication rate was 31.3%(45/144), and the reoperation rate was 9.72%(14/144). Among them, 8 patients were reoperated due to fusion cage subsidence or displacement, accounting for 57.14%(8/14) of reoperation. The fusion cage subsidence in this group had obvious characteristics. The monofactor analysis showed that the number of abnormal subsidence patients in the osteopenia or osteoporosis group, Stand-alone OLIF group, 2 or more segments fusion group, and endplate injury group was higher than that in the normal bone mass group, OLIF combined with pedicle screw fixation group, single segment fusion group, and no endplate injury group, and the comparison had statistical differences.@*CONCLUSION@#Cage subsidence is a common phenomenon after OLIF surgery. Preoperative osteopenia or osteoporosis, Stand-alone OLIF, 2 or more segments of fusion and intraoperative endplate injury may be important factors for postoperative fusion cage subsidence. Although there is no significant correlation between the degree of cage subsidence and clinical symptoms, there is a risk of cage migration, and prevention needs to be strengthened to reduce serious complications caused by fusion of cage subsidence, including reoperation.

Complicaciones del abordaje anterior de columna lumbar en una serie de 197 pacientes / Complications of the anterior approach to lumbar spine in a series of 197 patients

Objetivo: Analizar las complicaciones relacionadas con la cirugía de columna lumbar por vía anterior. materiales y métodos: Estudio descriptivo y retrospectivo de una serie de pacientes operados por abordaje anterior de la columna lumbar entre 2006 y 2019. La población estaba formada por 197 pacientes. Las variables consideradas fueron: edad, sexo, diagnóstico, plan quirúrgico (artrodesis anterior, doble vía combinada, revisión anterior, extracción del implante), niveles lumbares involucrados, complicaciones intraquirúrgicas inmediatas, tempranas o tardías. Se utilizó la clasificación de Clavien-Dindo para las complicaciones quirúrgicas. Resultados: Se evaluó a 197 pacientes, con una edad promedio de 53.39 años (106 mujeres, 53,81% y 91 hombres, 46,19%). El diagnóstico más frecuente fue discopatía degenerativa en 51 pacientes (25,89%). Treinta y cuatro (17,26%) sufrieron complicaciones: 4 inmediatas (2,03%), 22 (11,16%) tempranas y 9 (4,57%) tardías. La complicación inmediata más frecuente fue la lesión arterial (2 pacientes). La complicación temprana más frecuente fue la lesión del platillo vertebral (5 pacientes). La complicación tardía más frecuente fue la fractura del cuerpo vertebral (4 pacientes), dos pacientes fallecieron como consecuencia de las complicaciones. Conclusión: En nuestra serie, las complicaciones más frecuentes fueron: lesión vascular (inmediata), lesión del platillo vertebral (temprana) y fractura del cuerpo vertebral (tardía). Nivel de Evidencia: IV

Objective: To analyze complications related to the anterior approach to the lumbar spine. materials and methods: Descriptive and retrospective study of a series of patients who underwent surgery by an anterior approach to the lumbar spine between 2006 and 2019. The study population was 197 patients. The variables considered were age, gender, diagnosis, surgical plan, lumbar levels involved, and the presence of immediate, early or late complications. The Clavien-Dindo classification was used for surgical complications. Results: 197 patients were evaluated. The average age was 53.39 years, and there were 106 women (53.81%) and 91 men (46.19%). The most frequent diagnosis was degenerative disc disease in 51 patients (25.89%). 34 patients presented complications (17.26%): 4 immediate complications (2.03%), 22 early complications (11.16%), and 9 late complications (4.57%). The most frequent immediate complication was arterial injury (2 patients). The most frequent early complication was vertebral endplate injury (5 patients). The most frequent late complication was vertebral body fracture (4 patients). Two patients died as a consequence of their complications. Conclusion: In our series of patients, the most frequent complications were vascular injury (intraoperative), vertebral endplate injury (early), and vertebral body fracture (late). The author considers that the anterior approach to the lumbar spine performed by a team trained in this type of approach is a safe technique, with a low rate of complications. Level of Evidence: IV

Tratamiento endoscópico de la espondilodiscitis lumbar. Reporte de un caso y revisión bibliográfica / Endoscopic treatment of lumbar spondylodiscitis. Case report and literature review

Se describe el caso de un hombre de 62 años de edad, con múltiples comorbilidades que concurre a la consulta por dolor lumbar severo compatible con espondilodiscitis de T12-L1-L2. Se realizó una endoscopia con abordaje posterolateral izquierdo con técnica adentro-adentro para fines diagnóstico y terapéutico. Se aisló un germen y se administró un tratamiento antibiótico específico. Dada la buena evolución clínica del paciente, fue dado de alta a los 7 días de la cirugía, con buen manejo del dolor y antibióticos intravenosos en el domicilio. Se presenta una breve revisión bibliográfica. Nivel de Evidencia: IV

We describe the case of a 62-year-old male patient with multiple comorbidities who attended the outpatient clinic due to severe low back pain compatible with T12-L1-L2 spondylodiscitis. Endoscopy was performed with a left posterolateral approach and an all-inside technique for diagnostic and therapeutic purposes. A germ was isolated and treated with specific antibiotics. Due to the good clinical evolution, the patient was discharged 7 days after surgery with good pain management and home intravenous antibiotic therapy. A brief literature review is presented. Level of Evidence: IV

Influential factors related to functional status after full-endoscopic lumbar discectomy / 北京大学学报(医学版)

OBJECTIVE@#To explore the influential factors associated with functional status of those patients who undertook a full-endoscopic lumbar discectomy operation.@*METHODS@#A prospective study was conducted. A total of 96 patients who undertook a full-endoscopic lumbar discectomy operation and met inclusive criteria were enrolled in the study. The postoperative follow-up was held 1 month, 3 months and 6 months after operation. The self-developed record file was used to collect the patient's information and medical history. Visual analogue scale (VAS) score, Oswestry disability index (ODI) score, Gene-ralised anxiety disorder-7 (GAD-7) scale score and patient health questionnaire-9 (PHQ-9) scale score were applied to measure pain intensity, functional status, anxiety status and depression status. Repeated measurement analysis of variance was used to explore the ODI score 1 month, 3 months and 6 months after operation. Multiple linear regression was recruited to illuminate the influential factors associated with functional status after the operation. Logistic regression was employed to explore the independent risk factors related to return to work 6 months after operation.@*RESULTS@#The postoperative functional status of the patients improved gradually. The functional status of the patients 1 month, 3 months and 6 months after operation were highly positively correlated with the current average pain intensity. The factors influencing the postoperative functional status of the patients were different according to the recovery stage. One month and 3 months after operation, the factors influencing the postoperative functional status were the current average pain intensity; 6 months after operation, the factors influencing the postoperative functional status included the current average pain intensity, preoperative average pain intensity, gender and educational level. The risk factors influencing return to work 6 months after operation included women, young age, preoperative depression status and high average pain intensity 3 months after operation.@*CONCLUSION@#It is feasible to treat chronic low back pain with full-endoscopic lumbar discectomy operation. In the process of postoperative functional status recovery, medical staffs should not only take analgesic mea-sures to reduce the pain intensity experienced by the patients, but also pay attention to the impact of psychosocial factors on the recovery. Women, young age, preoperative depression status, and high average pain intensity 3 months after operation may delay return to work after the operation.

Percutaneous pedicle screw fixation combined expandable tubular retractor in the treatment of spinal metastases / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effectiveness of percutaneous pedicle screw fixation combined expandable tubular retractor in the treatment of patients with spinal metastases.@*METHODS@#In the study, 12 patients of spinal metastases treated with percutaneous pedicle screw fixation combined expandable tubular retractor in our hospital were retrospectively reviewed between June 2017 and October 2019. Among the 12 patients, 9 were males and 3 were females; the median age was 62.5 years [(65.1±2.9) years]. The decompression segment of 7 patients was located at the lower thoracic spine (including 1 patient with incomplete paraplegia) and the decompression segment of 5 patients was located at the lumbar spine; Tomita score was 6.0±0.6. Perioperative data of the patients were reviewed. Visual analog scale (VAS score), Karnofsky score, and Eastern Cooperative Oncology Group (ECOG) score were compared before and after surgery. The patient's survival, adjuvant treatment, and internal fixation failure were observed in the follow-up period.@*RESULTS@#All the 12 patients had a successful operation with percuta-neous pedicle screw fixation combined expandable tubular retractor. The average operative time, blood loss, and blood transfused of the patients were (247.0±14.6) min, (804.2±222.3) mL and (500.0±100.0) mL, respectively. The average amount of drainage was (240.8±79.3) mL. Drainage tubes were pulled out early postoperative [(3.2±0.3) d], allowing early mobilization. The patients discharged (7.8±0.8) d postoperative. All the patients were followed up for 6-30 months, and the average overall survival time was (13.6±2.4) months. During the follow-up period, 2 patients experienced screw displacement, the internal fixation was stable after conservative treatment and no revision surgery was performed. The VAS of the patients was 7.1±0.2 before surgery, which decreased to 2.3±0.1 and 2.8±0.4 at 3 and 6 months after surgery (P < 0.05). The Karnofsky score of the patients was 59.2±1.9 before surgery, which increased to 75.0±1.9 and 74.2±3.1 at 3 and 6 months after surgery (P < 0.05). The ECOG of the patients was 2.3±0.2 before surgery, which decreased to 1.7±0.1 and 1.7±0.2 at 3 and 6 months after surgery (P < 0.05).@*CONCLUSION@#For selected patients with spinal metastases, minimally invasive surgical treatment of spinal metastases (percutaneous pedicle screw internal fixation combined with expandable tubular retractor) can effectively relieve the clinical symptoms and improve the quality of life, with satisfactory clinical outcome.

Efficacy analysis of autologous facet joint bone block in lumbar interbody fusion of osteoporosis patients / 北京大学学报(医学版)

OBJECTIVE@#To compare and analyze the feasibility of autologous facet joint bone block as an alternative to polyetheretherketone (PEEK) cage in lumbar intervertebral fusion surgery for patients with osteoporosis.@*METHODS@#From December 2018 to June 2021, the case data of patients with osteoporosis (T value ≤ -2.5 on dual energy X-ray bone density) who underwent posterior lumbar interbody fusion in the Fourth Medical Center, Chinese PLA General Hospital were retrospectively reviewed. All the cases were followed up for no less than 12 months and were divided into two groups according to the differences of interbody fusion materials: the autologous facet joint bone block group (autogenous bone group) and the PEEK cage group (PEEK group). The general data [such as age, gender, body mass index (BMI), primary diagnosis, distribution of fusion segments, bone mineral density of lumbar (BMD), incidence of preoperative complications], the perioperative data (such as duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate), and the incidence of postoperative complications were compared between the two groups. Imaging parameters (disc height, lumbar lordosis angle, segment lordosis angle, segmental lordosis angle, disc height improvement rate, and fusion rate) and lumbar functional scores [visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedics Association (JOA) score for lower back pain] were compared to evaluate the clinical efficacy between the kinds of intervertebral fusion materials 1 week, 3 months and 6 months postoperative and at the last follow-up.@*RESULTS@#A total of 118 patients were enrolled, including 68 cases in the autogenous bone group and 50 cases in the PEEK group, there were no statistical differences in age, gender, BMI, primary diagnosis, distribution of fusion segments, BMD, incidence of preoperative complications, duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate, incidence of postoperative complications, all the preoperative imaging parameters and all the lumbar function scores between the two groups (P>0.05). Postoperative superficial surgical site infections occurred in 3 patients in the autogenous bone group and 2 patients in the PEEK group. At the last follow-up, 3 cases of intervertebral graft collapse occurred in the autogenous bone group and 5 cases in the PEEK group, 1 case of graft subsidence in the autogenous bone group and 1 case in the PEEK group. All the imaging parameters showed significant differences between postoperation and preoperation (P < 0.05), and all the imaging parameters showed significant differences between 1 week and 3 months postoperative in both groups (P < 0.05). The height, angle of fusion gap in the autogenous bone group were lower than those in the PEEK group 1 week postoperatively (P < 0.05), and the fusion gap height improvement rate in the autogenous bone group was lower than that in the PEEK group (P < 0.05). The cases in both groups started to show final fusion 3 months after surgery, and the fusion rate in the autogenous bone group was 75% 6 months postoperatively, which was significantly higher than the rate of 56% in the PEEK group (P < 0.05), and there was no statistically significant difference in the final fusion rate between the two groups (P>0.05). The ODI, the postoperative VAS score was significantly lower than that in preoperation, while the postoperative JOA score was significantly higher than that in preoperation (P < 0.05). The ODI was lower while the JOA score was higher of the autogenous bone group than that of the PEEK group 6 months postoperatively (P < 0.05).@*CONCLUSION@#In osteoporosis patients, good interbody fusion rate and improvement of lumbar vertebral function can be obtained by using autologous facet joint bone block or PEEK cage, while the fusion rate and the improvement of lumbar function with autologous facet joint bone block are better than those with PEEK cage 6 months post-operatively. PEEK cage is superior to autologous facet joint bone block in intervertebral distraction and improvement of lumbar lordosis. Significant disc space subsidence occurred in osteoporotic patients within 3 months after lumbar interbody fusion, and the subsidence of PEEK cage was more obvious than that of autologous facet joint bone block.

Effect of neuroelectrophysiological changes on the clinical manifestations and surgical outcomes of lumbar degenerative diseases / 中国骨伤

OBJECTIVE@#To evaluate the effects of electromyography on the clinical manifestations and prognosis after posterior lumbar interbody fusion(PLIF) of degenerative lumbar diseases.@*METHODS@#A retrospective analysis was performed on 68 patients with degenerative lumbar diseases, including 29 males and 39 females, aged 21 to 84 years old, who underwent electromyogram (EMG) from January 2018 to October 2019. The patients were divided into negative and positive groups according to whether theresults of EMG was normal or abnormal, PLIF surgery was performed in both groups. The preoperative duration of illness, postoperative recovery time, operative time, intraoperative blood loss, postoperative ambulation time and length of postoperative hospital stay were recorded. The clinical efficacy was evaluated by visual analogue scale(VAS) of low back and lower limb, the Japanese Orthopedic Association(JOA) score before and after operation.@*RESULTS@#All patients were follow-up from 26 to 39 months. The subjective symptoms, clinical signs, daily activities and JOA total scores after operation in two groups were significantly higher than those before preoperation(P<0.05);the clinical signs score and total JOA score in the negative group at 3 months after operation were higher than those in the positive group(P<0.05). The VAS score of leg pain in the negative group after 1 and 3 months was less than that in the positive group(P<0.05). Patients 's illness time, postoperative recovery time, hospitalization time and implantation time in the negative group were shorter than those in the positive group(P<0.05). At other time points, there was no significant difference in low pain VAS, leg pain VAS, JOA scores in the two groups(P>0.05). There was no significant difference in the operation time and intraoperative bleeding volume between the two groups(P>0.05).@*CONCLUSION@#Patients with normal electromyography had shorter disease duration than ones with abnormal electromyography in lumbar degenerative disease;after PLIF, patients with normal electromyography recovered faster than ones with abnormal electromyography, but the results of electromyography had no effect on the final prognosis of PLIF surgery.

Research progress of Wallis dynamic stabilization system for lumbar degenerative diseases / 中国骨伤

Wallis dynamic stabilization system is a surgical approach in the non-fusion technique of lumbar spine, consisting of interspinous blockers and dacron artificial ligaments that provide stability to the spine while maintaining a degree of motion in the affected segment. Recent studies have demonstrated the significant benefits of Wallis dynamic stabilization system in treating lumbar degenerative diseases. It not only improves clinical symptoms, but also effectively delays complications such as adjacent segmental degeneration. This paper aims to review the literature related to the Wallis dynamic stabilization system and degenerative diseases of the lumbar spine to describe the long-term prognostic effect of this system in the treatment of such diseases. This review provides a theoretical basis and reference for selecting surgical methods to treat degenerative diseases of the lumbar spine.

Observation of early clinical efficacy of unilateral biportal endoscopy technique in the treatment of lumbar postoperative adjacent segmental diseases / 中国骨伤

OBJECTIVE@#To investigate early clinical efficacy of unilateral biportal endoscopy technique for the treatment of lumbar postoperative adjacent segmental diseases.@*METHODS@#Fourteen patients with lumbar postoperative adjacent segmental diseases were treated with unilateral biportal endoscopy technique from June 2019 to June 2020. Among them, there were 9 males and 5 females, aged from 52 to 73 years old, and the interval between primary and revision operations ranged from 19 to 64 months. Adjacent segmental degeneration occurred after lumbar fusion in 10 patients and after lumbar nonfusion fixation in 4 patients. All the patients received unilateral biportal endoscopy assisted posterior unilateral lamina decompression or unilateral approach to the contralateral decompression. The operation time, postoperative hospital stay and complications were observed. The visual analogue scale (VAS) of low back pain and leg pain, Oswestry Disability Index (ODI), modified Japanese Orthopaedic Association (mJOA) score were recorded before operation and at 3 days, 3 months, and 6 months after operation.@*RESULTS@#All procedures were successfully completed. Surgical duration ranged from 32 to 151 min. Postoperative CT showed adequate decompression and preservation of most joints. Out of bed walking 1 to 3 days after surgery, postoperative hospital stay was 1 to 8 days, and postoperative follow-up was 6 to 11 months. All 14 patients returned to normal life within 3 weeks after surgery, and VAS, ODI, and mJOA scores improved significantly at 3 days and 3, 6 months after surgery. One patient occurred cerebrospinal fluid leak after operation, received local compression suture, and the wound healed after conservative treatment. One patient occurred postoperative cauda equina neurologic deficit, which was gradually recovered about 1 month after rehabilitation therapy. One patients advented transient pain of lower limbs after surgery, and the symptoms were relieved after 7 days of treatment with hormones, dehydration drugs and symptomatic management.@*CONCLUSION@#Unilateral biportal endoscopy technique has a good early clinical efficacy in the treatment of lumbar postoperative adjacent segmental diseases, which may provide a new minimally invasive, non-fixation option for the treatment of adjacent segment disease.

Application of modified alternate negative pressure drainage instrument after posterior lumbar fusion / 中国骨伤

OBJECTIVE@#To investigate the effect of modified alternate negative pressure drainage on postoperative outcomes after posterior lumbar interbody fusion (PLIF) surgery.@*METHODS@#This was a prospective study involving 84 patients who underwent PLIF surgery between January 2019 and June 2020. Of these patients, 22 had single-segment surgery and 62 had two-segment surgery. Patients were grouped by surgical segment and admission sequence:the observation group included patients with a single-segment surgery, and the control group included patients with a two-segment surgery. Natural pressure drainage was given to 42 patients in the observation group (modified alternate negative pressure drainage group) after surgery, which was then changed to negative pressure drainage after 24 hours. In the control group, 42 patients were given negative pressure drainage after surgery, which was then changed to natural pressure drainage after 24 hours. The total drainage volume, drainage time, maximum body temperature at 24 hours and 1 week after surgery, and drainage-related complications were observed and compared between the two groups.@*RESULTS@#There was no significant difference in operative time and intraoperative blood loss between the two groups. The postoperative total drainage volume was significantly lower in the observation group (456.69±124.50) ml than in control group (572.36±117.75) ml, and the drainage time was significantly shorter in the observation group (4.95±1.31) days than in the control group (4.00±1.17) days. Maximum body temperature at 24 hours after surgery was similar in both groups (37.09±0.31)°C in the observation group and (37.03±0.33)°C in the control group, while on the 1st week after surgery, it was slightly higher in the observation group (37.05±0.32)°C than in the control group (36.94±0.33)°C, but the difference was not significant. There were no significant differences in drainage-related complications, with one case(2.38%) of superficial wound infection in the observation group and two cases(4.76%) in control group.@*CONCLUSION@#Modified alternate negative pressure drainage after posterior lumbar fusion can reduce the drainage volume and shorten the drainage time without increasing the risk of drainage-related complications.

Causes of asymptomatic side limb pain after minimally invasive transforaminal lumbar interbody fusion / 中国骨伤

OBJECTIVE@#To investigate possible causes and preventive measures for asymptomatic pain in the limbs after minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF).@*METHODS@#Clinical data from 50 patients with lumbar degenerative disease who underwent MIS-TLIF between January 2019 and September 2020 were retrospectively analyzed. The group included 29 males and 21 females aged from 33 to 72 years old, with an average age of (65.3±7.13) years. Twenty-two patients underwent unilateral decompression, and 28 underwent bilateral decompression. The side(ipsilateral or contralateral) and site(low back, hip, or leg) of the pain were recorded before surgery, 3 days after surgery, and 3 months after surgery. The pain degree was evaluated using the visual analogue scale(VAS) at each time point. The patients were further grouped based on whether contralateral pain occurred postoperatively (8 cases in the contralateral pain group and 42 in the no contralateral pain group), and the causes and preventive measures of pain were analyzed.@*RESULTS@#All surgeries were successful, and the patients were followed up for at least 3 months. Preoperative pain on the symptomatic side improved significantly, with the VAS score decreasing from (7.00±1.79) points preoperatively to (3.38±1.32) points at 3 days postoperatively and (3.98±1.17) points at 3 months postoperatively. Postoperative asymptomatic side pain (contralateral pain) occurred in 8 patients within 3 days after surgery, accounting for 16% (8/50) of the group. The sites of contralateral pain included the lumbar area (1 case), hip(6 cases), and leg (1 case). The contralateral pain was significantly relieved 3 months after surgery.@*CONCLUSION@#More cases of contralateral limb pain occur after unilateral decompression MIS-TLIF, and the reason may include contralateral foramen stenosis, compression of medial branches, and other factors. To reduce this complication, the following procedures are recommended: restoring intervertebral height, inserting a transverse cage, and withdrawing screws minimally.

Effect of adjacent segmental facet joint degeneration on adjacent segment disease after lumbar fusion and fixation / 中国骨伤

OBJECTIVE@#To explore the effect of facet joint degeneration in adjacent segments on the incidence of adjacent segment disease (ASD) after lumbar fusion and fixation.@*METHODS@#A retrospective analysis was performed on 138 patients who underwent L5S1 posterior lumbar interbody fusion (PLIF) from June 2016 to June 2019. Patients were divided into a degeneration group (68 cases) and a non-degenerative group (70 cases) based on the presence or absence of L4,5 facet joint degeneration before surgery (graded using the Weishaupt standard). Age, gender, body mass index (BMI), follow-up time, and preoperative L4,5 intervertebral disc degeneration (graded using the Pfirrmann standard) were collected for both groups. Clinical outcomes were evaluated using the visual analogue scale (VAS) and Oswestry disability index (ODI) at 1 and 3 months after surgery. The incidence and time of ASD after surgery were analyzed.@*RESULTS@#There were no significant differences between the two groups in age, gender, BMI, follow-up time, or preoperative L4,5 intervertebral disc degeneration. Both groups showed significant improvement in VAS and ODI at 1 and 3 months after surgery (P<0.001), with no significant difference between the groups(P>0.05). However, there was a statistically significant difference in the incidence and timing of ASD between the groups (P<0.05). The degeneration group had 2 cases of ASD in gradeⅠdegeneration, 4 cases of ASD in gradeⅡdegeneration, and 7 cases of ASD in grade Ⅲ degeneration. There was a statistically significant difference between the number of patients with grade Ⅲ degeneration and those with gradesⅠandⅡASD (P<0.0167, Bonferroni correction).@*CONCLUSION@#Preoperative degeneration of adjacent articular processes will increase the risk of ASD after lumbar fusion fixation, whereas gradeⅢ degeneration will further increase the risk.

Comparison of clinical effect and muscle injury imaging between oblique lateral lumbar interbody fusion and transforaminal lumbar interbody fusion in the treatment of single-segment degenerative lumbar spinal stenosis / 中国骨伤

OBJECTIVE@#To compare the efficacy and muscle injury imaging between oblique lateral lumbar interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) in the treatment of single-segment degenerative lumbar spinal stenosis.@*METHODS@#The clinical data of 60 patients with single-segment degenerative lumbar spinal stenosis who underwent surgical treatment from January 2018 to October 2019 was retrospectively analyzed. The patients were divided into OLIF groups and TLIF group according to different surgical methods. The 30 patients in the OLIF group were treated with OLIF plus posterior intermuscular screw rod internal fixation. There were 13 males and 17 females, aged from 52 to 74 years old with an average of (62.6±8.3) years old. And 30 patients in the TLIF group were treated with TLIF via the left approach. There were 14 males and 16 females, aged from 50 to 81 years old with an average of (61.7±10.4) years old. General data including operative time, intraoperative blood loss, postoperative drainage volume, and complications were recorded for both groups. Radiologic data including disc height (DH), the left psoas major muscle, multifidus muscle, longissimus muscle area, T2-weighted image hyperintensity changes and interbody fusion or nonfusion were observed. Laboratory parameters including creatine kinase (CK) values on postoperative 1st and 5th days were analyzed. Visual analogue scale(VAS) and Oswestry disability index(ODI) were used to assess clinical efficacy.@*RESULTS@#There was no significant difference in the operative time between two groups(P>0.05). The OLIF group had significantly less intraoperative blood loss and postoperative drainage volume compared to the TLIF group(P<0.01). The OLIF group also had DH better recovery compared to the TLIF group (P<0.05). There were no significant differences in left psoas major muscle area and the hyperintensity degree before and after the operation in the OLIF group (P>0.05). Postoperativly, the area of the left multifidus muscle and longissimus muscle, as well as the mean of the left multifidus muscle and longissimus muscle in the OLIF group, were lower than those in the TLIF group (P<0.05) .On the 1st day and the 5th day after operation, CK level in the OLIF group was lower than that in the TLIF group(P<0.05). On the 3rd day after operation, the VAS of low back pain and leg pain in the OLIF group were lower than those in the TLIF group (P<0.05). There were no significant differences in the ODI of postoperative 12 months, low back and leg pain VAS at 3, 6, 12 months between the two groups(P>0.05). In the OLIF group, 1 case of left lower extremity skin temperature increased after the operation, and the sympathetic chain was considered to be injured during the operation, and 2 cases of left thigh anterior numbness occurred, which was considered to be related to psoas major muscle stretch, resulting in a complication rate of 10% (3/30). In the TLIF group, one patient had limited ankle dorsiflexion, which was related to nerve root traction, two patients had cerebrospinal fluid leakage, and the dural sac was torn during the operation, and one patient had incision fat liquefaction, which was related to paraspinal muscle dissection injury, resulting in a complication rate of 13% (4/30). All patients achieved interbody fusion without cage collapse during the 6- month follow-up.@*CONCLUSION@#Both OLIF and TLIF are effective in the treatment of single-segment degenerative lumbar spinal stenosis. However, OLIF surgery has obviously advantages, including less intraoperative blood loss, less postoperative pain, and good recovery of intervertebral space height. From the changes in laboratory indexes of CK and the comparison of the left psoas major muscle, multifidus muscle, longissimus muscle area, and high signal intensity of T2 image on imaging, it can be seen that the degree of muscle damage and interference of OLIF surgery is lower than that of TLIF.

Clinical and radiologic comparison between oblique lateral interbody fusion and minimally invasive transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis / 中国骨伤

OBJECTIVE@#To compare the short-term clinical efficacy and radiologic differences between oblique lateral interbody fusion(OLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for degenerative lumbar spondylolisthesis.@*METHODS@#A retrospective analysis was performed on 58 patients with lumbar spondylolisthesis treated with OLIF or MIS-TLIF from April 2019 to October 2020. Among them, 28 patients were treated with OLIF (OLIF group), including 15 males and 13 females aged 47 to 84 years old with an average age of (63.00±9.38) years. The other 30 patients were treated with MIS-TLIF(MIS-TLIF group), including 17 males and 13 females aged 43 to 78 years old with an average age of (61.13±11.10) years. General conditions, including operation time, intraoperative blood loss, postoperative drainage, complications, lying in bed, and hospitalization time were recorded in both groups. Radiological characteristics, including intervertebral disc height (DH), intervertebral foramen height (FH), and lumbar lordosis angle (LLA), were compared between two groups. The visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate the clinical effect.@*RESULTS@#The operation time, intraoperative blood loss, postoperative drainage, lying in bed, and hospitalization time in OLIF group were significantly less than those in the MIS-TLIF group (P<0.05). The intervertebral disc height and intervertebral foramen height were significantly improved in both groups after the operation (P<0.05). The lumbar lordosis angle in OLIF group was significantly improved compared to before the operation(P<0.05), but there was no significant difference in the MIS-TLIF group before and after operation(P>0.05). Postoperative intervertebral disc height, intervertebral foramen height, and lumbar lordosis were better in the OLIF group than in the MIS-TLIF group (P<0.05). The VAS and ODI of the OLIF group were lower than those of the MIS-TLIF group within 1 week and 1 month after the operation (P<0.05), and there were no significant differences in VAS and ODI at 3 and 6 months after the operation between the two groups(P>0.05). In the OLIF group, 1 case had paresthesia of the left lower extremity with flexion-hip weakness and 1 case had a collapse of the endplate after the operation;in the MIS-TLIF group, 2 cases had radiation pain of lower extremities after decompression.@*CONCLUSION@#Compared with MIS-TLIF, OLIF results in less operative trauma, faster recovery, and better imaging performance after lumbar spine surgery.

Analysis of the causes and clinical results of vertebral fracture during oblique lateral lumbar interbody fusion / 中国骨伤

OBJECTIVE@#To analyze the causes of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy, summarize the clinical results, and propose preventive measures.@*METHODS@#Retrospective analysis was made on the data of 8 cases of lumbar spondylopathy and vertebral fracture treated by oblique lateral interbody fusion in three medical centers from October 2014 to December 2018. All were female, aged from 50 to 81 years with an average of 66.4 years. Disease types included 1 case of lumbar degenerative disease, 3 cases of lumbar spinal stenosis, 2 cases of lumbar degenerative spondylolisthesis and 2 cases of lumbar degenerative scoliosis. Preoperative dual energy X-ray bone mineral density test showed that 2 cases had T-value >-1 SD, 2 cases had T-value -1 to -2.5 SD, and 4 cases had T-value <-2.5 SD. Single segment fusion was in 5 cases, two segment fusion in 1 case and three segment fusion in 2 cases. Four cases were treated with OLIF Stand-alone and 4 cases were treated with OLIF combined with posterior pedicle screw fixation. Postoperative imaging examination showed vertebral fracture, and all of them were single vertebral fracture. There were 2 cases of right lower edge fracture of upper vertebral body at fusion segment, 6 cases of lower vertebral body fracture at fusion segment, and 6 cases with endplate injury and fusion cage partially embedded in vertebral body. Three cases of OLIF Stand-alone were treated with pedicle screw fixation via posterior intermuscular approach, while one case of OLIF Stand-alone and four cases of OLIF combined with posterior pedicle screw fixation were not treated specially.@*RESULTS@#The 5 cases of initial operation and 3 cases of reoperation did not show wound skin necrosis or wound infection. The follow-up time was from 12 to 48 months with an average of 22.8 months. Visual analogue scale (VAS) of low back pain was preoperative decreased from 4 to 8 points (averagely 6.3 points) and postoperative 1 to 3 points (averagely 1.7 points) at the final follow-up. Oswestry disability index (ODI) was preoperative 39.7% to 52.4% (averagely 40.2%), and postoperative 7.9% to 11.2% (averagely 9.5%) at the final follow-up. During the follow-up, there was no loosening or fracture of the pedicle screw system, and no lateral displacement of the fusion cage;however, the fusion cage at the vertebral fracture segment had obvious subsidence. The intervertebral space height of vertebral fracture segment was preoperaive 6.7 to 9.2 mm (averagely 8.1 mm), and postoperative 10.5 to 12.8 mm (averagely 11.2 mm). The improvement rate after operation was 37.98% compared to preoperative. The intervertebral space height at final follow-up was 8.4 to 10.9 mm (averagely 9.3 mm), and the loss rate was 16.71% compared with that after operation. At the final follow-up, interbody fusion was achieved in all cases except for one that could not be identified.@*CONCLUSION@#The incidence of vertebral fracture during oblique lateral interbody fusion in the treatment of lumbar spondylopathy is lower, and there are many reasons for fracture, including preoperative bone loss or osteoporosis, endplate injury, irregular shape of endplate, excessive selection of fusion cage, and osteophyte hyperplasia at the affected segment. As long as vertebral fracture is found in time and handled properly, the prognosis is well. However, it still needs to strengthen prevention.

Research progress of different minimally invasive spinal decompression in lumbar spinal stenosis / 中国修复重建外科杂志

OBJECTIVE@#To review the application and progress of different minimally invasive spinal decompression in the treatment of lumbar spinal stenosis (LSS).@*METHODS@#The domestic and foreign literature on the application of different minimally invasive spinal decompression in the treatment of LSS was extensively reviewed, and the advantages, disadvantages, and complications of different surgical methods were summarized.@*RESULTS@#At present, minimally invasive spinal decompression mainly includes microscopic bilateral decompression, microendoscopic decompression, percutaneous endoscopic lumbar decompression, unilateral biportal endoscopy, and so on. Compared with traditional open surgery, different minimally invasive spinal decompression techniques can reduce the operation time, intraoperative blood loss, and postoperative pain of patients, thereby reducing hospital stay and saving treatment costs.@*CONCLUSION@#The indications of different minimally invasive spinal decompression are different, but there are certain advantages and disadvantages. When patients have clear surgical indications, individualized treatment plans should be formulated according to the symptoms and signs of patients, combined with imaging manifestations.

Early-effectiveness of unilateral biportal endoscopic laminectomy in treatment of two-level lumbar spinal stenosis / 中国修复重建外科杂志

OBJECTIVE@#To analyze the early effectiveness of unilateral biportal endoscopy (UBE) laminectomy in the treatment of two-level lumbar spinal stenosis (LSS).@*METHODS@#The clinical data of 98 patients with two-level LSS treated with UBE between September 2020 and December 2021 were retrospectively analyzed. There were 53 males and 45 females with an average age of 59.9 years (range, 32-79 years). Among them, there were 56 cases of mixed spinal stenosis, 23 cases of central spinal canal stenosis, and 19 cases of nerve root canal stenosis. The duration of symptoms was 1.5- 10 years, with an average of 5.4 years. The operative segments were L 2, 3 and L 3, 4 in 2 cases, L 3, 4 and L 4, 5 in 29 cases, L 4, 5 and L 5, S 1 in 67 cases. All patients had different degrees of low back pain, among of which 76 cases were with unilateral lower extremity symptoms and 22 cases were with bilateral lower extremity symptoms. There were 29 cases of bilateral decompression in both segments, 63 cases of unilateral decompression in both segments, and 6 cases of unilateral decompression and bilateral decompression of each segment. The operation time, intraoperative blood loss, total incision length, hospitalization stay, ambulation time, and related complications were recorded. Visual analogue scale (VAS) score was used to assess the low back and leg pain before operation and at 3 days, 3 months after operation, and at last follow-up. The Oswestry disability index (ODI) was used to evaluate the functional recovery of lumbar spine before operation and at 3 months and last follow-up after operation. Modified MacNab criteria was used to evaluate clinical outcomes at last follow-up. Imaging examinations were performed before and after operation to measure the preservation rate of articular process, modified Pfirrmann scale, disc height (DH), lumbar lordosis angle (LLA), and cross-sectional area of the canal (CAC), and the CAC improvement rate was calculated.@*RESULTS@#All patients underwent surgery successfully. The operation time was (106.7±25.1) minutes, the intraoperative blood loss was (67.7±14.2) mL, and the total incision length was (3.2±0.4) cm. The hospitalization stay was 8 (7, 9) days, and the ambulation time was 3 (3, 4) days. All the wounds healed by first intention. Dural tear occurred in 1 case during operation, and mild headache occurred in 1 case after operation. All patients were followed up 13-28 months with an average of 19.3 months, and there was no recurrence or reoperation during the follow-up. At last follow-up, the preservation rate of articular process was 84.7%±7.3%. The modified Pfirrmann scale and DH were significantly different from those before operation ( P<0.05), while the LLA was not significantly different from that before operation ( P=0.050). The CAC significantly improved ( P<0.05), and the CAC improvement rate was 108.1%±17.8%. The VAS scores of low back pain and leg pain and ODI at each time point after operation significantly improved when compared with those before operation, and the differences between each time points were significant ( P<0.05). According to the modified MacNab criteria, 63 cases were excellent, 25 cases were good, and 10 cases were fair, with an excellent and good rate of 89.8%.@*CONCLUSION@#UBE laminectomy is a safe and effective technique with little trauma and fast recovery for two-level LSS and the early effectiveness is satisfactory.

Preoperative standing to prone spinal-pelvic sagittal parameter changes in old traumatic spinal fractures with kyphosis / 中国修复重建外科杂志

OBJECTIVE@#To investigate the changes in spinal-pelvic sagittal parameters from preoperative standing to prone position in old traumatic spinal fractures with kyphosis.@*METHODS@#The clinical data of 36 patients admitted between December 2016 and June 2021 for surgical treatment of old traumatic spinal fractures with kyphosis, including 7 males and 29 females, aged from 50 to 79 years (mean, 63.9 years), were retrospectively analyzed. Lesion segments included 2 cases of T 11, 12 cases of T 12, 2 cases of T 11, 12, 4 cases of T 12 and L 1, 12 cases of L 1, 2 cases of L 2, 1 case of L 2, 3, and 1 case of L 3. The disease duration ranged from 4 to 120 months, with an average of 19.6 months. Surgical procedures included Smith-Petersen osteotomy in 4 cases, Ponte osteotomy in 6 cases, pedicle subtraction osteotomy in 2 cases, and improved fourth level osteotomy in 18 cases; the remaining 6 cases were not osteotomized. The bone mineral density ranged from -3.0 to 0.5 T, with a mean of -1.62 T. The spinal-pelvic sagittal parameters from preoperative standing to prone positions were measured, including local kyphosis Cobb angle (LKCA), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and PI and LL mismatch (PI-LL). The kyphotic flexibility=(preoperative standing LKCA-preoperative prone LKCA)/preoperative standing LKCA×100%. Spinal-pelvic sagittal parameters were compared between standing position and prone position before operation, and Pearson correlation was used to judge the correlation between the parameters of standing position and prone position before operation.@*RESULTS@#When the position changed from standing to prone, LKCA and TK decreased significantly ( P<0.05), while SS, LL, PT, and PI-LL had no significant difference ( P>0.05). Pearson correlation analysis showed that LL was significantly correlated with SS and PI-LL in both standing and prone positions ( P<0.05), and the correlation strength between LL and SS in prone position was higher than that in standing position. In the standing position, LKCA was significantly correlated with SS and PT ( P<0.05). However, when the position changed from standing to prone, the correlation between LKCA and SS and PT disappeared, while PT and PI-LL was positive correlation ( P<0.05). The kyphotic flexibility was 25.13%-78.79%, with an average of 33.85%.@*CONCLUSION@#For the patients of old traumatic spinal fractures with kyphosis, the preoperative LKCA and TK decrease significantly from standing position to prone position, and the correlation between spinal and pelvic parameters also changed, which should be taken into account in the formulation of preoperative surgical plan.

Application of back-forward Bending CT localization image in the prediction of proximal junctional kyphosis after spinal deformity surgery in adults / 中国修复重建外科杂志

OBJECTIVE@#To investigate the feasibility of predicting proximal junctional kyphosis (PJK) in adults after spinal deformity surgery based on back-forward Bending CT localization images and related predictive indicators.@*METHODS@#A retrospective analysis was performed for 31 adult patients with spinal deformity who underwent posterior osteotomy and long-segment fusion fixation between March 2017 and March 2020. There were 5 males and 26 females with an average age of 62.5 years (range, 30-77 years). The upper instrumented vertebrae (UIV) located at T 5 in 1 case, T 6 in 1 case, T 9 in 13 cases, T 10 in 12 cases, and T 11 in 4 cases. The lowest instrumented vertebrae (LIV) located at L 1 in 3 cases, L 2 in 3 cases, L 3 in 10 cases, L 4 in 7 cases, L 5 in 5 cases, and S 1 in 3 cases. Based on the full-length lateral X-ray film of the spine in the standing position before and after operation and back-forward Bending CT localization images before operation, the sagittal sequence of the spine was obtained, and the relevant indexes were measured, including thoracic kyphosis (TK), lumbar lordosis (LL), local kyphosis Cobb angle (LKCA) [the difference between the different positions before operation (recovery value) was calculated], kyphosis flexibility, hyperextension sagittal vertical axis (hSVA), T 2-L 5 hyperextension C 7-vertebral sagittal offset (hC 7-VSO), and pre- and post-operative proximal junctional angle (PJA). At last follow-up, the patients were divided into PJK and non-PJK groups based on PJA to determine whether they had PJK. The gender, age, body mass index (BMI), number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, osteotomy grading, and related imaging indicators were compared between the two groups. The hC 7-VSO of the vertebral body with significant differences between groups was taken, and the receiver operating characteristic curve (ROC) was used to evaluate its accuracy in predicting the occurrence of PJK.@*RESULTS@#All 31 patients were followed up 13-52 months, with an average of 30.0 months. The patient's PJA was 1.4°-29.0° at last follow-up, with an average of 10.4°; PJK occurred in 8 cases (25.8%). There was no significant difference in gender, age, BMI, number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, and osteotomy grading between the two groups ( P>0.05). Imaging measurements showed that the LL recovery value and T 8-L 3 vertebral hC 7-VSO in the PJK group were significantly higher than those in the non-PJK group ( P>0.05). There was no significant difference in hyperextension TK, hyperextension LL, hyperextension LKCA, TK recovery value, LL recovery value, kyphosis flexibility, hSVA, and T 2-T 7, L 4, L 5 vertebral hC 7-VSO ( P>0.05). T 8-L 3 vertebral hC 7-VSO was analyzed for ROC curve, and combined with the area under curve and the comprehensive evaluation of sensitivity and specificity, the best predictive index was hC 7-L 2, the cut-off value was 2.54 cm, the sensitivity was 100%, and the specificity was 60.9%.@*CONCLUSION@#Preoperative back-forward Bending CT localization image can be used to predict the occurrence of PJK after posterior osteotomy and long-segment fusion fixation in adult spinal deformity. If the patient's T 8-L 2 vertebral hC 7-VSO is too large, it indicates a higher risk of postoperative PJK. The best predictive index is hC 7-L 2, and the cut-off value is 2.54 cm.

Back-forward bending CT in simulated surgical position to evaluate the remaining real angle and flexibility of thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture / 中国修复重建外科杂志

OBJECTIVE@#To introduce a scout view scanning technique of back-forward bending CT (BFB-CT) in simulated surgical position for evaluating the remaining real angle and flexibility of thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture.@*METHODS@#A total of 28 patients with thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture who met the selection criteria between June 2018 and December 2021 were included in the study. There were 6 males and 22 females with an average age of 69.5 years (range, 56-92 years). The injured vertebra were located at T 10-L 2, including 11 cases of single thoracic fracture, 11 cases of single lumbar fracture, and 6 cases of multiple thoracolumbar fractures. The disease duration ranged from 3 weeks to 36 months, with a median of 5 months. All patients received examinations of BFB-CT and standing lateral full-spine X-ray (SLFSX). The thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), local kyphosis of injured vertebra (LKIV), lumbar lordosis (LL), and the sagittal vertical axis (SVA) were measured. Referring to the calculation method of scoliosis flexibility, the kyphosis flexibility of thoracic, thoracolumbar, and injured vertebra were calculated respectively. The sagittal parameters measured by the two methods were compared, and the correlation of the parameters measured by the two methods was analyzed by Pearson correlation.@*RESULTS@#Except LL ( P>0.05), TK, TLK, LKIV, and SVA measured by BFB-CT were significantly lower than those measured by SLFSX ( P<0.05). The flexibilities of thoracic, thoracolumbar, and injured vertebra were 34.1%±18.8%, 36.2%±13.8%, and 39.3%±18.6%, respectively. Correlation analysis showed that the sagittal parameters measured by the two methods were positively correlated ( P<0.001), and the correlation coefficients of TK, TLK, LKIV, and SVA were 0.900, 0.730, 0.700, and 0.680, respectively.@*CONCLUSION@#Thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture shows an excellent flexibility and BFB-CT in simulated surgical position can obtain the remaining real angle which need to be corrected surgically.