Abstract:This CT guided endoscopic lumbar discectomy is a surgical mode developed by the author's team on the basis of endoscopic discectomy under C-arm fluoroscopy for individualized treatment of lumbar disc herniation. Performing this procedure might be divided into four aspects, including basic construction, preoperative preparation, operation manipulation and postoperative rehabilitation. Each aspect needs the detailed supporting measures accordingly, involving hardware factors such as equipment, or software measures such as medical staff training and patient cooperation. After more than 10 years of innovation and practice, more than 5 000 cases experience has been accu- mulated with mature characteristics. In this paper, we summarize our experience to provide a reference for junior clinician.

Abstract:With the development of neonatal intensive care techniques, more and more infants with low gestational age, low body weight and in critical condition do survive, whereas which maybe also lead upgrading incidence of cerebral palsy (CP). A large number of studies have proved that the wearing of lower limb orthotics plays a very important role in improving the motor function and posture of CP children. It can be used to limit ankle plantar flexion, knee recurvature and knee flexion, further improve walking speed and increase walking stability, and achieve the purpose of improving gait. The 3D printing is a personalized and customized process, and can be combined with computeraided design, mechanical simulation and other modern corrective techniques to give the orthotics better performance. In this article, 19 ex- perts in orthopaedics, rehabilitation and related fields discussed on the issue of 3D printed orthoses for lower extremity of the CP children and formed a consensus, involving definition, classification, design, manufacture and apply indication of 3D orthoses, as well as clinical su- pervision of whole application cycle.

Abstract:[Objective] To explore the incidence and related factors of cerebrospinal fluid leakage (CSFL) in posterior total laminectomy for decompression of thoracic ossification ligamentum flavum to provide a reference for clinical prevention of CSFL. [Methods] A retrospec- tive cohort study was conducted on patients who received posterior total laminectomy for decompression of thoracic ossification of ligamen- tum flavum between August 2015 and August 2021. According to whether CSFL happened, the patients were divided into the CSFL group and non-CSFL group. The univariate comparison, and multiple binary logic regression were conducted to search the factors related to CSFL. [Results] Of the 108 patients included in this study, 28 patients had CSFL, accounting for 25.93%. In term of univariate comparison, the CS- FL group had significantly higher ratio of preoperative limb paralysis (P＜0.05); significantly less residual rate of spinal canal area, the residu- al rate of diameter of the canal on the midline and the residual rate of the sagittal diameter on the images (P＜0.05); additionally, significantly higher ratio of intraoperative conventional bone chisels used (P＜0.05), significantly more number of segments involved (P＜0.05), as well as significantly longer operation time and hospital stay than the non-CSFL group (P＜0.05). However, there were no significant differences be- tween the two groups in age, gender, BMI, course of disease, bladder and bowel dysfunction, preoperative JOA score, drinking history, smok- ing history, preoperative comorbidities, such as hypertension, diabetes, Sato classification, MRI grade, residual rate of transverse and antero- posterior diameter, residual rate of paramedian diameter and surgical site (P＞0.05). As result of logistic regression, the more segments in- volved (OR=4.272, P=0.007) and small residual rate of spinal canal area (OR=0.903, P＜0.001) was an independent risk factor for CSFL. [Conclusion] More thoracic segments involved and less residual rate of spinal canal area are associated with higher risk of CSFL. The corre- sponding measures should be taken to reduce the occurrence of CSFL.

Abstract:[Objective] To establish an appropriate and effective blood transfusion evaluation model by analyzing the influencing factorsof perioperative blood transfusionin spinal surgery, so as to provide appropriate suggestions and evidence for clinical practice, optimize bloodtransfusion management, save blood resources to the maximum extent and reduce transfusion- related risks. [Methods] A total of 268 pa-tients who received spinal surgery in our hospital from January 2020 to June 2021 were retrospectively analyzed and divided into transfusiongroup and non-transfusion group according to perioperative blood transfusion or not. The basic demographic data, comorbidities, preopera-tive status and operative documents were recorded. The independent impacting factors of blood transfusion were analyzed by univariate com-parison and binary multiple logistic regression, while prediction model of blood transfusion volume was constructed by multiple linear regres-sion. [Results] In term of univariate comparison, the transfusion group proved significantly higher than the non-transfusion group in ratio oftrauma, liver disease, the lumbar surgically involved, decompression and fusion, and no anticoagulants used (P＜0.05). The former was signifi-cantly worse than the latter in the preoperative ASA grade and incision healing grade (P＜0.05). In addition, the transfusion group had signifi-cantly lower preoperative Hb, HCT and Alb, whereas significantly greater number of segments surgically involved, operative time, intraopera-tive blood loss and postoperative drainage volume than the non-transfusion group (P＜0.05). However, there were no statistically significantdifferences between the two groups in age, sex, BMI, diabetes, hypertension, and kidney disease, and preoperative PT and APTT (P＞0.05).As results of logistic regression, the intraoperative blood loss (OR=1.010, P＜0.05) and operation time (OR=1.020, P＜0.05) were the indepen-dent risk factor for blood transfusion, while the preoperative HCT (OR=0.844, P＜0.05) was a protective factor for blood transfusion. Regard-ing multiple stepwise regression of 51 patients who received transfusion, the number of segments surgically involved (Xs) (B=2.118, P=0.001) and preoperative Alb (Xa) (B=-0.439, P=0.017) were the main factors of predicating blood transfusion volume (Y), with the regres-sion equation as follows: Y=16.063+2.118Xs-0.439Xa. [Conclusion] Improving patients' preoperative condition and reducing surgical trau-ma is the way to reduce blood transfusion in spinal surgery. The number of segments surgically involved and preoperative Alb are importantfactors in the evaluation and transfusion volume.

Abstract:[Objective] To evaluate the clinical outcomes of microwave ablation combined with vertebroplasty and pedicle screw fixa- tion (MWVPS) for spinal metastases. [Methods] A retrospective study was performed on 37 patients who received surgical treatment for tho- racolumbar metastatic tumors in our hospital from January 2018 to April 2020. Based on preoperative doctor-patient communication, 15 pa- tients received MWVPS, while the other 22 patients received percutaneous vertebroplasty (PVP) alone. The perioperative, follow-up and im- aging data were compared between the two groups. [Results] All patients in both groups had surgical procedures performed successfully with- out spinal cord and nerve root injury during the operation. The MWVPS group consumed significantly longer operation time, associated with significantly more intraoperative blood loss, more bone cement injected and longer hospital stay than the PVP group (P＜0.05), while the MWVPS group had significantly lower ratio of bone cement leakage than PVP group (P＜0.05), regardless of the fact that the MWVPS group had significantly higher rate of incision complication than the PVP group (P＜0.05). With time of follow-up lasted for (14.9±1.0) months on a mean, the VAS and ECOG scores significantly continuously decreased in MWVPS group, while curve-likely changed in PVP group (P＜ 0.05). Although there were no significant differences in VAS and ECOG scores between the two groups before surgery and 3 months after sur- gery (P＞0.05), the MWVPS group proved significantly superior to the PVP group at the latest follow-up in terms of VAS and ECOG scores (P＜0.05). Radiographically, the height of the affected vertebrae significantly increased (P＜0.05), whereas the local kyphotic Cobb angle sig- nificantly decreased in both groups 6 months after surgery compared with those before surgery (P＞0.05). There was no significant difference in the vertebral height and Cobb angle of the affected vertebrae between the two groups before surgery (P＞0.05), whereas the MWVPS group was significantly better than PVP group in above parameters at 6 months and the last follow-up (P＜0.05). [Conclusion] Microwave ablation combined with vertebroplasty and pedicle screw fixation is superior to vertebroplasty alone in terms of safety and medium-term efficacy for spinal metastases.

Abstract:[Objective] To evaluate the early clinical outcomes of arthroscopic correction combined with intraarticular injection of plate-let rich plasma (PRP) for femoroacetabular impingement (FAI). [Methods] A retrospective study was performed on 32 patients who under-went arthroscopic surgery for FAI in our hospital from January 2021 to January 2022. According to doctor-patient communication, 17 pa-tients received hip arthroscopy combined with intraarticular injection of PRP (PRP group), while the remaining 15 patients received hip ar-throscopy only without PRP injection (non-PRP group). The perioperative period, follow-up and imaging data of the two groups were com-pared. [Results] All patients in both groups had operation performed successfully without neurovascular injury and other serious complica-tions. There were no significant differences in operation time, total incision length, intraoperative blood loss, postoperative walking time, inci-sion healing grade and hospital stay between the two groups (P＜0.05). All patients were followed up for an average of (12.8±0.9) months, andthere was no significant difference in the time to resume full weight-bearing activities between the two groups (P＞0.05). The VAS score de-creased significantly (P＜0.05), whereas the Harris score, extension-flexion ROM and internal-external rotation ROM scores increased signif-icantly in both groups over time postoperatively (P＜0.05). The PRP group proved significantly superior to the non-PRP group in terms ofVAS score [(3.1±1.5) vs (4.2±1.3), P＜0.05], Harris score [(70.5±4.4) vs (64.2±2.8), P＜0.05], extension-flexion ROM [(102.6±5.5)° vs (95.3±6.4)°, P＜0.05] and internal-external rotation ROM [ (38.3±4.2)° vs (35.2±2.8)°, P＜0.05] 1 month postoperatively, whereas which became notstatistically significant between the two groups at 6 months after surgery and the last follow-up (P＞0.05). Radiographically, the α angle, later-al center edge angle (LCEA) and femoral head-neck offset (FHNO) significantly improved (P＜0.05), but T?nnis classification remained un-changed (P＞0.05) in both groups at 1 month after surgery and the latest follow-up. At any corresponding time points, there was no statistical significance in the above image indexes between the two groups (P＞0.05). [Conclusion] Hip arthroscopy combined with PRP in the treat- ment of FAI does reduce pain, improve hip function and improve early clinical outcomes.

Abstract:[Objective] To compare the clinical outcomes of two osteotomies in tibia lengthening for correction of lower limb shorteningsecondary to poliomyelitis. [Methods] A retrospective study was performed on 50 patients who underwent leg lengthening with humerus in-tramedullary nail combined with external frame from March 2008 to July 2017. Based on doctor-patient communication, 25 patients had thetibial metaphyseal osteotomized transversely (transverse group), while the other 25 patients had tibial metaphyseal osteotomy performed inthe inverted “V” shape (V-shaped group). The documents regarding to treatment period, follow-up and images were compared betweenthe two groups. [Results] All patients had corresponding surgical procedures performed successfully. The V-shaped group proved signifi-cantly superior to the transverse group in terms of ambulation time [(129.5±5.7)days vs (146.2±4.2)days, P＜0.05], frame bearing time [(67.2±1.3)days vs (69.9±2.3)days, P＜0.05], bone healing index [(51.2±6.4)d/cm vs (53.9±4.4)d/cm, P＜0.05], alignment deviation ratio [0 (0.0%) vs4 (16.0%), P＜0.05], knee flexion contracture rate [1(4.0%) vs 6(24.0%), P＜0.05]. There were no significant differences in operation time, to-tal incision length, intraoperative blood loss, incision healing grade, hospital stay, length of tibia lengthened, elongation rate, stretch index,incidence of osteogenesis poor, nail tract infection and foot drop between the two groups (P＞0.05). All the patients in both groups were fol-lowed up for a mean of (4.1±0.9) years, and the V-shaped group returned to full weight-bearing activity significantly earlier than the trans-verse group [(191.1±8.2)days vs (211.5±4.6)days, P＜0.05]. The VAS score significantly decreased (P＜0.05), while HSS score significantly in-creased (P＜0.05), and knee and ankle range of motion (ROM) remained unchanged over time in both groups (P＞0.05), which were not statisti-cally significant between the two groups at any time point accordingly (P＞0.05). Radiographically, the V-shaped group proved significantlysuperior to the transverse group in term of bone healing in lengthened area [0/I/II/III/IV, (0/1/18/6/0) vs (0/2/20/3/0), P＜0.05] 1 month before frame removal, [(0/0/19/6/0) vs (0/0/22/3/0), P＜0.05] at the time of frame removal, [(0/0/5/12/8) vs (0/0/7/14/4), P＜0.05] 3 months after frame removal. There were no significant differences in femorotibial angle and Kellgren-Lawrence grade of ankle between the two groups at any corresponding time points (P＞0.05). [Conclusion] Both osteotomy techniques do achieve satisfactory lengthening outcomes. In contrast, the inverted V osteotomy has less impacts on the knee, and less chance of knee flexion contracture and axis deviation, which is conducive to bone healing.

Abstract:Venous thromboembolism (VTE) secondary to major joint arthroplasty is characterized by high morbidity and mortality with high risk, especially post-thrombotic syndrome, which seriously affects patients' function and quality of life due to vascular endothelial dam- age and other factors. Currently it remains unclear which anticoagulant is more appropriate, although several clinical studies have shown that aspirin may provide effective VTE prophylaxis. Therefore, this paper reviewed the mechanism of aspirin for VTE prevention and related re- search progress at home and abroad in hip or knee arthroplasty to provide a reference for clinicians.

Abstract:The thoracolumbar fascia (TLF) separates the paravertebral muscles from the posterior abdominal wall muscles, and all lay- ers of the thoracolumbar fascia form a complex that is particularly important in maintaining stability adjacent to the thoracolumbar segment, especially the lower lumbar and sacroiliac joints. Lumbar spine diseases are often accompanied by changes in the TLF. However, the presen- tations have not attracted widespread clinical attention at present, while imaging evaluation has not formed a unified standard. Accurate iden- tification and study of morphological and functional changes of the TLF by imaging is very critical for the clinical treatment and prevention of low back pain. Therefore, the author summarizes the imaging performance and deficiencies of TLF in patients with lower back pain, and looks forward to new technologies in order to improve our understanding of TLF imaging performance.

Abstract:Cervical lesions mainly include cervical vertebrae and soft tissue lesions. Due to the small size of C₂ vertebra, it is relatively difficult to conduct puncture biopsy and tumor therapy with risk to damage the carotid artery, vertebral artery, posterior bilateral cervical nerve, anterior throat, spinal cord and other key adjacent structures. In recent years, with the increasing number of patients with cervical tu- mor and cervical metastatic tumor, biopsy and other therapeutic managements are often needed to determine the nature of the lesion for diag- nosis and subsequent treatment. In this paper, the surgical approach, clinical efficacy and complications of C₂ vertebral biopsy and vertebro- plasty were reviewed, in order to provide reference for clinicians.

Abstract:Posttraumatic arthritis is the most common and typical secondary arthritis. A number of experimental studies in vitro and in vivo have demonstrated that the expression of periostin in the cartilage matrix after injury increases and leads to the development and pro- gression of posttraumatic arthritis. The periostin interacts with the extracellular matrix of chondrocytes as upstream factors of multiple signal- ing pathways to affect the metabolism of the extracellular matrix of chondrocytes. In contrast to primary osteoarthritis, the nature and timing of posttraumatic arthritis are often known, and thus provide a unique window for intervention in the disease. However, surgical treatment has not reduced the incidence of traumatic arthritis. Therefore, in-depth researches on the mechanism of periostin playing in the occurrence and development of posttraumatic arthritis might be helpful to provide a new approach for the treatment of posttraumatic arthritis.

Abstract:[Objective] To analyze the three-dimensional kinematic characteristics of the lumbar facet joint (LFJ) activity when stand- ing. [Methods] Ten volunteers without lumbar disease were recruited, and underwent high- resolution CT and dural fluoroscopy examina- tions. The lumbar spine model of the volunteers was established matched with the images obtained by the dural fluoroscopic imaging system to reproduce the instantaneous motion state of LFJ, and analyze its kinematic characteristics, such as displacement and rotation angle. [Results] In term of flexion and extension, the maximum rotation range was (3.6±2.7)° at L4~L5 segments (P＜0.05), while the maximum transla- tion range was at L5S1 segments (P＜0.05). The left-right translation range at L3~L4 was significantly greater on the right side than on the left side [(0.9±0.5)mm vs (0.4±0.5)mm, P＜0.05], while which at L4~L5 segment proved greater on the left than the right [(1.6±0.8)mm vs (1.1±0.4) mm, P＜0.05]. In term of lateral bending motion, the maximum rotation range was (4.9±4.4)° in L3~L4 segments (P＜0.05), while the maximum translation range was at L3-4 segments (P＜0.05). The translational range of LFJ at the L4~L5 level was significantly greater on the left than on the right [(0.7±0.5)mm vs (0.6±0.4)mm, P＜0.05]. In term of rotation motion, the rotation range of L3~L4 was the largest (2.6±1.7)°, and the translation range of L3~L4 was significantly larger on the right than the left [(0.7±0.5)mm vs (0.6±0.4)mm, P＜0.05]. [Conclusion] The move- ment characteristics of LFJ are related to its movement mode, with complex postures dominated by coupled motion.

Abstract:[Objective] To explore the effects of metabolic obesity on bone metabolism in male Sprague-Dawg rats in youth (17 weeks of age) and adulthood (27 weeks of age). [Methods] Forty 5-week-old male SD rats were randomly divided into the normal diet (ND) group and high-fat diet (HFD) group, and were fed with ND and HFD until 17 and 27 weeks, respectively. The serum bone metabolism markers were detected, micro CT examination and three point bending mechanical test were performed. [Results] Although there were no significant differences in serum Ca, P, PINP and CTX between the two groups at 17 weeks of age (P＞0.05), the HFD group had significantly lower PINP, while significantly higher CTX than the ND group at 27 weeks of age (P＜0.05). The body weight and muscle mass of the animals significantly increased with age (P＜0.05). Compared with the ND group, the Tb.vBMD, Tb.BV /TV and Tb.N significantly decreased (P＜0.05), while Tb. Sp significantly increased in the HFD group at 17 weeks of age (P＜0.05). In addition, the Tb.vBMD, Tb.BV /TV, Tb.th, Tb.n significantly de- creased (P＜0.05) while the Tb. Sp and SMI significantly increased in HFD group at 24 weeks of age (P＜0.05). Compared with those at 17 weeks of age, the maximum load, maximum fracture load, energy absorption, toughness, ultimate tensile strength and elastic modulus signifi- cantly increased in the ND group at 27 weeks of age (P＜0.05), while the maximum load and energy absorption significantly increased in the HFD group (P＜0.05), without significant difference in other biomechanical indexes (P＞0.05). Despite there was no significant difference in the above indexes between the two groups at 17 weeks of age (P＜0.05), HFD group got significantly decreased above items compared with the ND group at 24 weeks of age (P＜0.05). [Conclusion] This metabolic obesity does reduce formation markers, while increase bone resorption markers. The bone microstructure changes appear in the adolescents, while the bone microstructure damage worsens in the adult with bone strength decreases

Abstract:[Objective] To introduce the surgical technique and preliminary clinical results of antibiotic-loaded calcium sulfate com- bined with platelet-rich plasma for treatment of chronic osteomyelitis of the distal femur. [Methods] From January 2017 to June 2020, 15 pa- tients received abovementioned therapy for Cierny-Mader type III chronic osteomyelitis in the distal femur. In the first-stage operation, the cortical bone margin over the infected lesion were drilled with a high-speed drill, fenestrated with a thin osteotome, debrided to remove all the sclerosing bone, abscess and inflammatory tissue, and rinsed with normal saline and Entoiodine repeatedly. The proximal and distal med- ullary cavities were opened by gradual drill bits, and negative-pressure closed drainage was placed. A week later, the second-stage opera- tion was conducted through the original incision. After debridement, sensitive antibiotics loaded calcium sulfate particles were prepared, then mixed with PRP to fill the medullary cavity with drainage placed. [Results] All patients had operations successfully completed with no vascular nerve injury and other serious complications. All patients were followed up for an average of (26.1±6.3) months. At the last followup the pain VAS score and HSS knee score of the affected limb were significantly improved (P＜0.05). The images showed good osteogenesis at the lesion site. [Conclusion] This antibiotic-loaded calcium sulfate combined with platelet-rich plasma does effectively treat chronic os- teomyelitis of the distal femur.

Abstract:[Objective] To introduce the surgical technique and preliminary clinical outcome of adjustable suture-plate loop for open re- duction and internal fixation of acute acromioclavicular dislocation through mini incisions. [Methods] A total of 15 patients received aboves- aid surgical treatment for Tossy type III acute acromioclavicular dislocation. A small longitudinal incision was made on the lateral body sur- face of the coracoid process, while a small transvers incision was made on the anterior side of the distal clavicle to expose the coracoid pro- cess and clavicle. As the locator was positioned on the distal clavicle and the base of coracoid process, a guide needle was inserted, and bone tunnels 4.5mm in diameter was drilled. An adjustable suture- plate loop with a four- leaf clover- shaped titanium plate was introduced through the tunnels, and then the loop was tightened to reduce and fix the acromioclavicular joint. [Results] All patients had operation per- formed successfully with operation time of (36.5±15.2) min and total incision length of (4.3±0.2) cm, and got incisions healed well. At the lat- est follow-up lasted for (12.7±3.3) months, the VAS score and Constant-Murley score, as well as abduction, external rotation, internal rota- tion, and forward flexion range of motion (ROM) of the shoulder significantly improved compared with those preoperatively (P＜0.05). [Conclusion] This adjustable suture-plate loop for open reduction and internal fixation of acute acromioclavicular dislocation through mini inci- sions has the advantages of less iatrogenic trauma, shorter operation time, and surgical operation under direct vision without needing the tech- nique basis of shoulder arthroscopy.

Abstract:[Objective] To explore the clinical outcomes of modified single-screw Scarf osteotomy for correction of hallux valgus. [Methods] From June 2020 to February 2021, a total of 23 patients (30 feet) underwent the modified single-screw Scarf osteotomy for treatment of hallux valgus in our hospitals. The clinical and imaging data were compared between themselves preoperatively and at the last follow-up. [Results] All patients were successfully operated on without postoperative complications, and followed up for more 12 months. Compared with those preoperatively, the VAS score significantly reduced (P＜0.05), while the AOFAS score significantly increased at the latest follow up (P＜0.05). Radiographically, the hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), and Handy-Clapham tibial sesamoid scale significantly declined at the latest follow up compared with those preoperatively (P＜0.05). [Conclusion] This modified single-screw Scarf osteotomy does achieve satisfactory clinical outcomes for correction of hallux valgus.

Abstract:[Objective] To evaluate the short-term clinical outcomes of WaveflexTM spinal system in the treatment of lumbar disc herni- ation in of adolescent. [Methods] A retrospective study was conducted on 23 adolescent patients who received extended interlaminar fenes- trated discectomy combined with internal fixation with WaveflexTM spinal system for intervertebral disc herniation in our hospital from June 2017 to December 2020. The clinical and imaging data were evaluated. [Results] All the 23 patients were successfully operated on without serious complications, whereas with the operation time of (73.8±5.5) min, and the intraoperative blood loss of (131.7±22.4) ml, and followed up from 12 to 36 months. As time went by (preoperative, 6 months after surgery and the last follow-up), the VAS score for lumbago [(5.4± 1.0), (2.3±0.6), (1.5±0.6), P＜0.001], the VAS score for leg pain [(6.5±0.9), (2.4±0.6), (1.4±0.5), P＜0.001], and ODI scores [(59.0±4.8), (19.7±2.9), (13.0±3.0), P＜0.001] were significantly reduced. Radiographically, the height of the intervertebral disc [(8.6±1.6)mm, (10.4±1.4) mm, (10.1±1.5)mm, P＜0.001] , the lumbar lordotic angle [(18.3±8.6)°, (24.7±7.4)°, (23.9±6.4)°, P＜0.001] , and Pfirrmann grade of disc de- generation (I/II/III/IV/V) [(0/6/15/2/0), (1/10/9/3/0), (2/13/4/4/0), P=0.009] significantly improved postoperatively compared with those pre- operatively. [Conclusion] This waveflex dynamic fixation does achieve satisfactory clinical consequences in short term for adolescent lum- bar disc herniation, which might be beneficial to maintain the height of intervertebral space and delay the degeneration of intervertebral disc.

Abstract:[Objective] To compare the clinical efficacy of three drainage methods after multi-segment transforaminal lumbar interbody fusion (TLIF). [Methods] From July 2019 to June 2020, a total of 104 patients who were undergoing TLIF for multilevel lumbar degenerative diseases in our department were divided into 3 group. After TLIF, 34 patients had intermittent negative pressure drainage (INPD), 37 pa- tients received continuous negative pressure drainage (CNPD), while the remaining 33 patients were treated by natural pressure drainage (NPD). The perioperative and follow-up data of the three groups were compared. [Results] All the patients in the 3 groups had TLIF per- formed smoothly. Although there were no significant differences in operative time and intraoperative blood loss among three groups (P＞0.05), the CNPD group proved significantly greater than the INPD and NPD groups in terms of drainage volume at the 1st postoperative day, total vol- ume of postoperative drainage and total drainage days (P＜0.05). However, the NPD group had significantly greater incision errhysis than the INPD and CNPD groups (P＜0.05). The VAS of leg pain and ODI significantly decreased (P＜0.05), while the JOA scores significantly in- creased over time postoperatively in all the 3 groups (P＜0.05), whereas which proved not statistically significantly among the 3 groups at any corresponding time points (P＞0.05). [Conclusion]The intermittent negative pressure drainage after multilevel TLIF does significantly re- duce the drainage volume, reduce postoperative wound bleeding, and shorten total drainage days, is a safe and effective drainage method.

Abstract:[Objective] To investigate the relationship between the intervertebral disc height and the Pfirrmann classification for inter- vertebral disc degeneration in low back pain. [Methods] A retrospective study was conducted on the lumbar MRI data of 151 patients who visited the Department of Spinal Surgery of our hospital for low back pain from January 2021 to June 2022. The intervertebral disc height was measured, and the degree of intervertebral disc degeneration were assessed by using Pfirrmann criteria. Spearman rank correlation was used to search the correlation between intervertebral space height and Pfirrmann grade. [Results] The intervertebral disc height of the 151 pa- tients was ranked down-up as L_1~2, L₅~S₁, L_2~3, L_4~5 and L_3~4, which was statistically significant [(9.4±0.6)mm, (10.4±1.5)mm, (10.6±0.8)mm, (11.8±0.8)mm, (11.8±0.8)mm, P＜0.05]. The Pfirrmann grade for intervertebral disc degeneration was ranked mild-severe as L_1~2, L_2~3, L_3~4, L₅~S₁, L_4~5, with statistically significant difference among the levels (P＜0.05). All the intervertebral disc heights from L_1~2 to L₅~S₁ were nega- tively correlated with the extents of degeneration in term of Pfirrmann grade significantly (r=-0.576, r=-0.578, r=-0.411, r=-0.409, r=- 0.828, P＜0.001). [Conclusion] The intervertebral disc height might be used as a simple parameter to evaluate the degree of lumbar interver- tebral disc degeneration, which has certain clinical reference value.

Abstract:[Objective] To evaluate the significance of ultrasound-guided selective nerve root block (SNRB) in determining the responsi- ble segment of multi-level lumbar degenerative lesions. [Methods] From September 2019 to August 2021, 72 patients received SNRB to identify the responsible segments of multi-level lumbar degenerative diseases, and then corresponding surgical managements. The docu- ments regarding to SNRB and surgical procedures were evaluated. [Results] Of the 72 patients, 30 (41.7%) got the responsible nerve root lo- cated at the first puncture, 12 (16.7%) were located by the second puncture, and 22 (30.6%) were located by the third time, whereas 8 (11.1%) failed to locate the responsible nerve root, with total positioning success rate of 88.9%. The operation time of SNRB ranged from 20 min to 30 min, with an average of (24.5±2.6)min, while the fluoroscopy performed ranged from 2 times to 5 times, with an average of (3.4±1.0) times. According to the results of imaging localization and SNRB, 12 (16.7% ) underwent single- level spinal canal decompression, 17 (23.6%) received single- level decompression combined with discectomy, 10 (13.9%) were treated with muti-segment decompression, 15 (20.8%) underwent multilevel decompression combined with discectomy, and 18 (25.0%) had decompression combined instrumented fusion performed. All patients had corresponding surgical procedures performed successfully without massive bleeding or nerve injury, and were fol- lowed up for more than 12 months. The VAS scores for lumbago and leg pain, as well as ODI scores significantly decreased (P＜0.05), while the JOA scores significantly increased over time (P＜0.05). [Conclusion] The SNRB might accurately locate the main responsible segments, narrow the extent of surgical decompression, and improve the efficiency of surgical treatment for multi-level lumbar degenerative diseases.