ABSTRACT
Objective To evaluate biomechanical properties of the nickel-titanium (NiTi) memory alloy stent and its in vitro biomechanical properties for lumbar interbody fusion. Methods The mechanical properties of the NiTi memory alloy stent were tested on mechanical testing machine. Moreover, lumbar interbody fusion was simulated on fresh lumbar specimens, and biomechanical properties of the NiTi memory alloy stent with matching bone graft for used for lumbar interbody fusion were analyzed and compared with the traditional box-shape cage. Results The maximum compressive strength of the NiTi memory alloy stent was ( 12 964 ± 962) N. The maximum deformation within the effective range of memory characteristics was (4. 68±0. 03) mm. The recovery rate of the NiTi memory alloy stent was up to 99. 86% . Compared with the intact lumbar model, the stability of the operative segment after the simulated lumbar interbody fusion using NiTi memory alloy stent alone was increased in the direction of anterior flexion, posterior extension, lateral flexion and rotation, which was equivalent to the box shape cage group (P>0. 05). After the combined use of autogenous bone granule and absorbable bone cement the ROM of the operative segment was further reduced (P0. 05). The pull-out strength of the NiTi memory alloy stent with matching bone graft group was significantly stronger than that of the box-shape cage group (P<0. 05). Conclusions The NiTi memory alloy stent in this study was designed with a matched bone granule-absorbable bone cement graft,which provided a new idea for the further optimization and development of lumbar interbody fusion. With excellent support and deformation properties, this NiTi memory alloy stent is biomechanical equivalent to the traditional box shape cage for lumbar interbody fusion, and can greatly improve the stability of surgical segment and the pull-out strength of implants after the combined use of autogenous bone granule and absorbable bone cement.
ABSTRACT
Objective To verify the biomechanical stability of oblique lateral interbody fusion ( OLIF) combinedwith different fixation methods for treating degenerative lumbar scoliosis (DLS) by three-dimensional (3D) finite element analysis. Methods The L1-S1 3D finite element DLS model ( Model 1) was established, and then the OLIF (L2-5) at 3 contiguous levels of fusion and its combination with different internal fixation methods were simulated, namely, stand-alone OLIF model ( Model 2), vertebral screw fixation model ( Model 3), unilateral pedicle screw fixation model (Model 4) and bilateral pedicle screw fixation model (Model 5) were established,respectively. Under upright, flexion, extension, lateral bending and axial rotation states, range of motion (ROM) of fusion segments, as well as cage stress, internal fixation stress, and stress distribution were recorded and analyzed. Results Under six motion states, the overall ROM of fusion segments in Models 2-5 was smaller than that of Model 1. Compared with Model 1, the overall ROM reduction of Model 3 and Model 4 was larger than that of Model 2 and smaller than that of Model 5. Under flexion and extension, the overall ROM reduction of Model 4 and Model 5 was basically equal. Under left and right lateral bending, the overall ROM reduction of Model 3 and Model 5 was basically equal. Under all motion states, the peak stress of Model 3 and Model 4 fusion cage was larger than that of Model 5 and smaller than that of Model 2. The peak stresses of L2-3, L3-4 and L4-5 fusion cages in Model 3 increased by 5. 52% , 10. 96% and 7. 99% respectively compared with Model 5 under left lateral bending, and the peak stresses of L2-3, L3-4 and L4-5 fusion cages in Model 4 increased by 8. 70% , 7. 00% and 6. 99% respectively under flexion. Under all motion states, the peak stress of screw rod in Model 5 was smaller than that of Model 3 and Model 4, and the peak stresses of screw rod in Models 3-5 were the smallest in upright state. Conclusions The OLIF with unilateral pedicle screw fixation or vertebral screw fixation can provide favorable biomechanical stability of the fusion segment. The results provide some references for clinical application of OLIF technology in the treatment of DLS.
ABSTRACT
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.
Subject(s)
Male , Female , Humans , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Retrospective Studies , Spinal Fusion/methods , Lumbar Vertebrae/surgery , Treatment Outcome , PainABSTRACT
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.
Subject(s)
Male , Female , Humans , Middle Aged , Aged , Adult , Retrospective Studies , Lumbar Vertebrae/surgery , Spinal Fusion/methods , Minimally Invasive Surgical Procedures/methods , Pain, Postoperative , Treatment OutcomeABSTRACT
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.
Subject(s)
Male , Female , Humans , Middle Aged , Aged , Aged, 80 and over , Retrospective Studies , Spinal Stenosis/surgery , Blood Loss, Surgical , Lumbar Vertebrae/surgery , Spinal Fusion/methods , Treatment Outcome , Pain, Postoperative , Muscles , Minimally Invasive Surgical Procedures/methodsABSTRACT
Objective To analyze the biomechanical characteristics of lumbar fusion by 3 internal fixation methods using three-dimensional (3D) finite element (FE) method. Methods The FE fixation models of physiological L4-5, unfixed fusion L4-5, translaminar facet screw (TLFS), lumbar pedical screw+translaminar facet screw (LPS+TLFS), bilateral pedical screw (BPS) with complete osteotomy or partial osteotomy of facet joint were established, respectively. The biomechanical characteristics of L4 centrum and implants under six motion states (spinal flexion, extension, lateral bending and axial rotation) in L4-5 fusion model and three fixation models were compared by FE analysis. Results The average maximal displacements of L4 centrum in L4-5 unfixed fusion model, TLFS model, TLFS+LPS model, BPS model were 1.410 8, 0.629 8, 0.336 9, 0.252 8 mm (complete osteotomy of facet joint) and 1.296 7, 0.844 9, 0.340 9, 0.273 8 mm (partial osteotomy of facet joint); the average maximal displacements of cage were 0.479 9, 0.319 5, 0.167 6, 0.126 4 mm (complete osteotomy of facet joint) and 0.378 7, 0.348 4, 0.183 5, 0.137 2 mm (partial osteotomy of facet joint)；the average maximum stresses of screws and rods during 6 motions in TLFS model, TLFS+LPS model, BPS model were 178.34, 79.55, 56.33 MPa (complete osteotomy of facet joint) and 142.29, 103.02, 59.69 MPa (partial osteotomy of facet joint). Conclusions In percutaneous transforaminal lumbar interbody fusion, the fixation effect of BPS model was similar to that of LPS+TLFS model. BPS model could achieve the best spinal stability, and LPS+TLFS model was also a good fixation method. The stability of TLFS model alone was relatively poor, but it was still better than that of cage bone graft without internal fixation. In the absence of internal fixation, preservation of the articular process significantly increased stability of the spine.
ABSTRACT
Objective To evaluate the biomechanical properties of lumbar interbody fusion with NiTi memory alloy stent-autogenous bone granule-absorbable bone cement. Methods The normal L3-5 segment finite element model (M0), L4-5 intervertebral fusion model with box fusion cage (M1), L4-5 intervertebral fusion model with NiTi memory alloy stent (M2) and L4-5 interbody fusion model with bone granule-absorbable bone cement for casting bone graft (M3) were constructed, respectively. The models were applied with mechanical loading to analyze the mechanical stability and the peak stress of L4 interior endplate. Results The range of motion (ROM) of L4-5 segment in M1 and M2 models was significantly lower than that of M0 model under flexion, extension, lateral flexion and axial rotation. In M3 model, the stability of the surgical segment was further improved and the peak stress of L4 interior endplate was much smaller than that of M1 and M2 models. Conclusions NiTi memory alloy stent and traditional box fusion cage have biomechanical equivalence when used alone in lumbar interbody fusion, and application of bone granule-absorbable bone cement for casting bone graft can further improve the stability and reduce the stress of endplate.
ABSTRACT
@#OBJECTIVE: The main objective of this study was to evaluate clinical and radiographic outcomes of computer minimally invasive transforaminal lumbar interbody fusion (CNMIS TLIF). METHODS: Blood loss, operating time, complications, and hospital stay were identified through chart review. Numeric rating scale (NRS) scores for pain were taken during recent follow-ups, and these were compared to the pre-operative scores. Three different examiners assessed the pre-operative lumbosacral spine radiographs. At a 2-years follow-up, the patients were evaluated with NRS and the radiographs reassessed by three other examiners. RESULTS: Seventy-four patients with a mean age of 54 years underwent CNMIS TLIF. Average blood loss was 300 mL, operative time was 4.5 hours, and the average length of hospital stay was 8.5 days. A total of four complications were noted in our study. There was an improvement of mean local lordosis and regional lordosis. The paired-sample t-test showed that the anterior, middle, and posterior disc heights at the cage level were significantly increased compared to the pre-operative values. CONCLUSION: CNMIS TLIF is a safe and efficient method to achieve spinal fusion. There was a significant improvement in clinical outcomes in terms of pain relief. Radiologic parameters such as local lordosis, regional lordosis, and anterior, middle, and posterior disc heights showed significant improvements at 2-years follow-up.
Subject(s)
Spinal Fusion , Minimally Invasive Surgical Procedures , ComputersABSTRACT
The human spine injury and various lumbar spine diseases caused by vibration have attracted extensive attention at home and abroad. To explore the biomechanical characteristics of different approaches for lumbar interbody fusion surgery combined with an interspinous internal fixator, device for intervertebral assisted motion (DIAM), finite element models of anterior lumbar interbody fusion (ALIF), transforaminal lumbar interbody fusion (TLIF) and lateral lumbar interbody fusion (LLIF) are created by simulating clinical operation based on a three-dimensional finite element model of normal human whole lumbar spine. The fusion level is at L4-L5, and the DIAM is implanted between spinous process of L4 and L5. Transient dynamic analysis is conducted on the ALIF, TLIF and LLIF models, respectively, to compute and compare their stress responses to an axial cyclic load. The results show that compared with those in ALIF and TILF models, contact forces between endplate and cage are higher in LLIF model, where the von-Mises stress in endplate and DIAM is lower. This implies that the LLIF have a better biomechanical performance under vibration. After bony fusion between vertebrae, the endplate and DIAM stresses for all the three surgical models are decreased. It is expected that this study can provide references for selection of surgical approaches in the fusion surgery and vibration protection for the postsurgical lumbar spine.
Subject(s)
Humans , Biomechanical Phenomena , Finite Element Analysis , Lumbar Vertebrae/surgery , Pedicle Screws , Range of Motion, Articular , Spinal Fusion , VibrationABSTRACT
【Objective】 To investigate the effect of adequate amount of tranexamic acid(TXA)before operation on blood loss and safety in posterior lumbar fusion with multiple segments. 【Methods】 A retrospective analysis was conducted on 105 patients with lumbar spinal stenosis, submitted to our hospital for multilevel PLIF, from March 2017 to December 2019. According to the intervention method, they were divided into control group, group A and group B (n =30, 39 and 36, respectively). TXA was not used in the control group. Dripping of saline solution(100 mL) containing TXA 2g and 1g was given in Group A and Group B, and extra intravenous pumping of TXA [10 mg/(kg·h)] during surgery was conducted in Group B besides the pre-operation dripping of TXA. Total blood loss, dominant blood loss, recessive blood loss, intraoperative blood loss, postoperative drainage volume, transfusion rate and hemoglobin (Hb), hematocrit (Hct), prothrombin time international standardized ratio (PT - INR), platelet count (Plt), D - dimer (D - D), C-reactive protein (CRP), neutrophil percentage (NP), alanine aminotransferase (ALT), and blood urea nitrogen (BUN) before and after operation were compared in the three groups. Postoperative drug-related adverse events were traced. 【Results】 1)The total blood loss, dominant blood loss(mL), intraoperative blood loss(mL), drainage volume(mL) within and after 24h after surgery, and the transfusion rate(%) in group A and B were 892.6±193.5 vs 887.7±320.8, 409.1±109.2 vs, 408.6±98.3, 193.7±69.3 vs 189.6±65.6, 130.5±53.4 vs 128.3±53.5, 63.1±17.6 vs 60.9±13.5 and 7.7 (3/39) vs 8.3 (3/36), respectively, which were significantly lower than that in group C as 1 296.8±329.2, 807.6±231.5, 270.9±65.5, 365.4±127.8, 172.3±66.4 and 36.7(11/30), respectively (P< 0.05). There were no significant differences in the above indexes between group A and group B (P < 0.05). The differences in recessive blood loss was not significant by groups(P<0.05). 2) Compared with pre-operation, the levels of Hb, Hct and Plt in the three groups at 3d after operation decreased: Hb(g/L) 91.5±14.0, 107.6±16.4 and 105.9±17.1; Hct(%) 25.6±3.1, 31.2±3.9 and 30.5±4.4; Plt(×109/L)146.6±31.8, 172.8 ±40.1 and 169.7±39.5(P < 0.05); while D-D, CRP and NP increased: D-D(mmol/L)365.6±67.1, 280.9±50.5 and 286.1±53.1; CRP(mg/L): 65.4±22.0, 53.4±19.6 and 56.8±17.7; NP(%): 87.3±15.6, 73.1±13.7, and 71.9±11.8(P < 0.05), and Pt-INR, ALT and BUN showed no significant changes (P > 0.05). The changes of Hb, Hct, Plt, D-D, CRP and NP in group A and B were significantly lower than those in group C at 3 days after operation [Hb (g/L) : 107.6±16.4, 105.9±17.1, 91.5±14.0; Hct (%) : 31.2±3.9, 30.5±4.4, 25.6±3.1; Plt (×109/L) : 172.8 ±40.1, 169.7±39.5, 146.6±31.8; D-D (mmol/L) : 280.9±50.5, 286.1±53.1, 365.6±67.1; CRP (mg/L) : 53.4±19.6, 56.8±17.7, 65.4±22.0; NP (%) : 73.1±13.7, 71.9±11.8, 87.3±15.6] (P < 0.05), and no significant differences in the above index were noticed between group A and B(P> 0.05).3)No lower limb deep vein thrombosis nor pulmonary embolism were found in group A and group B after operation, and all the incisions were healed in the first stage, and no serious complications such as drug allergy, cardiovascular and cerebrovascular accident, epidural hematoma, epilepsy occurred. 【Conclusion】 The preoperative TXA administration with sufficient single dose showed equivalent hemostatic effect in comparison with intraoperative continuous administration additional to preoperative dripping, which is simple and convenient and does not increase the risk of thrombosis.
ABSTRACT
BACKGROUND: More and more studies have shown that lumbar-pelvic parameters are closely related to the clinical effect and adjacent segment degeneration after lumbar fusion, but the effect of minimally invasive transforaminal interbody fusion on lumbar-pelvic parameters is not clear. OBJECTIVE: To evaluate the effect of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) on the lumbar-pelvic imaging parameters in patients with single-segment lumbar spinal stenosis. METHODS: The clinical data of 85 patients with single-segment lumbar spinal stenosis treated by MIS-TLIF and open-TLIF in the First Affiliated Hospital of Dali University from January 2015 to January 2017 were retrospectively analyzed, including 39 cases of MIS-TLIF operation (MIS-TLIF group) and 46 cases of open-TLIF operation (open-TLIF group). On the standing lateral lumbar X-ray containing bilateral femoral heads: lumbar lordosis, segmental lordosis, height of the intervertebral disc, the L1 axis and S1 distance, pelvic incidence, pelvic tilt, and sacral slope were measured, and the difference between pelvic incidence−lumbar lordosis and the ratio of lumbar lordosis/pelvic incidence were calculated. RESULTS AND CONCLUSION: (1) During the last follow-up, lumbar lordosis, height of the intervertebral disc, and sacral slope were increased in both groups compared with preoperative parameters, but pelvic tilt was decreased compared with preoperatively, and the difference was significant (P 0.05). (2) During the last follow-up, lumbar lordosis, segmental lordosis, height of the intervertebral disc, pelvic incidence, pelvic tilt, sacral slope, and the L1 axis and S1 distance were not significantly different compared with preoperative parameters (P > 0.05). (3) The difference between pelvic incidence−lumbar lordosis was significantly decreased at the last follow-up compared with preoperative parameters in the two groups (P 0.05). (4) Above results indicated that for single-segment lumbar spinal stenosis, MIS-TLIF has the same effect as open-TLIF in recovery of lumbar lordosis, intervertebral height, and improving lumbar-pelvic balance.
ABSTRACT
BACKGROUND: In the elderly patients with degenerative lumbar spinal stenosis, bilateral nerve root canal stenosis commonly shows only one side of symptoms. There is still controversy about whether or not decompression is needed on the side without symptoms or with less symptoms and how to operate. OBJECTIVE: To explore the safety and efficacy of robot-assisted unilateral-decompression using minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) technique by investigating a series of cases with the radiographic bilateral lumbar canal stenosis presenting with unilateral symptoms and by comparing clinical decompression effect and imaging changes before and after operation. METHODS: Cases with radiographic bilateral lumbar canal stenosis presenting with unilateral symptoms subjected to unilateral decompression on the affected side, interbody fusion and bilateral fixation after robot-assisted MIS-TLIF in the same treatment group were retrospectively analyzed. Operation time, intraoperative blood loss and complications were recorded. The vertebral canal cross-sectional area, intervertebral foramen height, intervertebral space height, and lumbar lordosis angle were examined before and after surgery. Visual analogue scale scores for low back pain and leg pain were assessed before and after surgery. Oswestry disability index was used to assess lumbar function before and after surgery. Macnab criteria were used to evaluate the efficacy at the final follow-up after surgery. RESULTS AND CONCLUSION: (1) Operation time was 110-235 minutes, averagely 169.4 minutes. Intraoperative blood loss was 70-180 mL, averagely 112.4 mL. (2) After 3-8 months of follow-up, the visual analogue scale scores of low back pain and lower extremity pain 1 month after surgery and in final follow-up were significantly lower than those before operation (both P 0.05). (6) It is concluded that robot-assisted unilateral-decompression MIS-TLIF obtained satisfactory effect in bilateral lumbar canal stenosis patients presenting with unilateral symptoms.
ABSTRACT
BACKGROUND: Decompression-fixation-fusion is the key to spinal surgery since early effective fixation to achieve intervertebral fusion can restore spinal stability in lumbar degenerative disease. OBJECTIVE: To compare biomechanical stability of fusion segment and adjacent segments of bilateral pedicle screw fixation, unilateral pedicle screw fixation and unilateral pedicle screw combined with contralateral translaminar facet screw fixation under transforaminal lumbar interbody fusion. METHODS: Eighteen fresh calf L3-5 specimens were selected. Different forms of fixation were conducted under transforaminal lumbar interbody fusion. The specimens were divided into group A (complete specimens) and group B (bilateral pedicle screws), group C (unilateral pedicle screws), and group D (unilateral pedicle screw combined with contralateral translaminar facet screw). The range of motion of adjacent segment L3-4 and fusion segment L4-5 in six directions of backward extension, forward bending, left bending, right bending, left rotation and right rotation and the stiffness of fusion segment L4-5 were tested. RESULTS AND CONCLUSION: (1) For the range of motion of fusion segment L4-5, the stability was highest in the group B in six directions, followed by group D, which showed similar results in rotation in the group B (P > 0.05). The stability of right curvature and left rotation in group C was insufficient, and there was no significant difference in range of motion between group A and group C (P > 0.05). The range of motion in group A was largest and the stability was worst in the six motion directions. (2) For the stiffness value of fusion segment L4-5, the stiffness value of group B was largest in six directions, which was significantly different from other groups (P 0.05). There was no significant difference between group C and group A in the range of motion of six directions (P > 0.05). (4) The results showed that the motion ramge of unilateral pedicle screw fixation in the right and left rotation directions was large in the early stage, which was close to that of the complete specimen group. There is a shortage of stability, so we need to use it carefully and grasp the indications strictly. Unilateral pedicle screw fixation combined with contralateral translaminar facet screw fixation improves the disadvantages of asymmetric fixation of unilateral pedicle screw, increases the stability of rotation and lateral bending, and avoids the influence of bilateral pedicle screw fixation on adjacent segments, thus becoming an effective clinical surgical treatment.
ABSTRACT
Objective@#We aimed to compare the clinical and radiological outcomes of midline lumbar fusion (MIDLF) versus minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) in patients with degenerative spondylolisthesis and/or stenosis in L4-L5 two years after surgery.@*Methods@#Consecutively treated patients with lumbar pathology who underwent MIDLF ( @*Results@#The mean operative time and hematocrit (HCT, Day 1) were significantly shorter and lower in MIDLF cases (174 min @*Conclusion@#MIDLF is comparable to MI-TLIF at L4-5 in clinical outcomes and fusion rates, and the results verified the meaningful advantage of using MIDLF for the elderly with osteoporosis.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Lumbar Vertebrae/surgery , Retrospective Studies , Spinal Fusion/methods , Treatment OutcomeABSTRACT
Objective: To analyze the restoration of intervertebral height and lordosis of fusion segment after open-transforaminal lumbar interbody fusion (Open-TLIF) and minimally invasive-TLIF (MIS-TLIF). Methods: Between January 2013 and February 2016, patients who treated with TLIF due to lumbar degenerative diseases and met the selection criteria were selected as the study objects. Among them, 41 patients were treated with open-TLIF (Open-TLIF group), 34 patients were treated with MIS-TLIF (MIS-TLIF group). There was no significant difference between the two groups ( P>0.05) in gender, age, body mass index, disease type, disease duration, pathological segment, and other general data. The intraoperative bleeding volume, hospital stay, visual analogue scale (VAS) score of waist and leg, and Oswestry disability index (ODI) were recorded before and after operation. The anterior disc height (ADH), posterior disc height (ADH), and segmental lordosis (SL) of fusion segment were measured by X-ray film before and at 6 months after operation. The differences of ADH, PDH, and SL between pre- and post-operation were calculated. Results: The intraoperative bleeding volume and hospital stay in Open-TLIF group were significantly higher than those in MIS-TLIF group ( t=14.619, P=0.000; t=10.021, P=0.000). All incisions healed by first intention without early complications. All patients were followed up 6-24 months (mean, 12.6 months) in Open-TLIF group and 6-24 months (mean, 11.5 months) in MIS-TLIF group. The preoperative VAS scores of waist and leg and ODI of the two groups significantly improved ( P0.05). Imaging examination showed the good intervertebral fusion. There was no significant difference in ADH, PDH, and SL between the two groups before operation and at 6 months after operation ( P>0.05). The differences of ADH, PDH, and SL between the two groups were not significant ( P>0.05). The ADH, PDH, and SL after operation significantly increased in the two groups ( P<0.05). Conclusion: Open-TLIF and MIS-TLIF show similar effectiveness and radiological change in the treatment of single lumbar degenerative diseases and the improved intervertebral height and lordosis, but MIS-TLIF can significantly reduce hospital stay and intraoperative blood loss.
ABSTRACT
Objective: To compare the effectiveness of modified transforaminal lumbar interbody fusion (modified-TLIF) and posterior lumbar interbody fusion (PLIF) for mild to moderate lumbar spondylolisthesis in middle-aged and elderly patients. Methods: The clinical data of 106 patients with mild to moderate lumbar spondylolisthesis (Meyerding classification≤Ⅱ degree) who met the selection criteria between January 2015 and January 2017 were retrospectively analysed. All patients were divided into modified-TLIF group (54 cases) and PLIF group (52 cases) according to the different surgical methods. There was no significant difference in preoperative clinical data of gender, age, disease duration, sliding vertebra, Meyerding grade, and slippage type between the two groups ( P>0.05). The intraoperative blood loss, operation time, postoperative drainage volume, postoperative bed time, hospital stay, and complications of the two groups were recorded and compared. The improvement of pain and function were evaluated by the visual analogue scale (VAS) score and Japanese Orthopedic Association (JOA) score at preoperation, 1 week, and 1, 6, 12 months after operation, and last follow-up, respectively. The effect of slip correction was evaluated by slip angle and intervertebral altitude at preoperation and last follow-up, and the effectiveness of fusion was evaluated according to Suk criteria. Results: All patients were followed up, the modified-TLIF group was followed up 25-36 months (mean, 32.7 months), the PLIF group was followed up 24-38 months (mean, 33.3 months). The intraoperative blood loss, operation time, postoperative drainage volume, postoperative bed time, and hospital stay of the modified-TLIF group were significantly less than those of the PLIF group ( P0.05). At last follow-up, the fusion rate of the modified-TLIF group and the PLIF group was 96.3% (52/54) and 98.1% (51/52), respectively, and no significant difference was found between the two groups ( χ2=0.000, P=1.000). About complications, there was no significant difference between the two groups in nerve injury on the opposite side within a week, incision infection, and pulmonary infection ( P>0.05). No case of nerve injury on the operation side within a week or dural laceration occurred in the modified-TLIF group, while 8 cases (15.4%, P=0.002) and 4 cases (7.7%, P=0.054) occurred in the PLIF group respectively. Conclusion: Modified-TLIF and PLIF are effective in the treatment of mild to moderate lumbar spondylolisthesis in middle-aged and elderly patients. However, modified-TLIF has relatively less trauma, lower blood loss, lower drainage volume, lower incidence of dural laceration and nerve injury, which promotes enhanced recovery after surgery.
ABSTRACT
Objective: To compare the clinical and radiological effectiveness of oblique lumbar interbody fusion (OLIF) and posterior lumbar interbody fusion (PLIF) in the treatment of Cage dislodgement after lumbar surgery. Methods: The clinical data of 40 patients who underwent revision surgery due to Cage dislodgement after lumbar surgery betweem April 2013 and March 2017 were retrospectively analyzed. Among them, 18 patients underwent OLIF (OLIF group) and 22 patients underwent PLIF (PLIF group) for revision. There was no significant difference between the two groups in age, gender, body mass index, intervals between primary surgery and revision surgery, number of primary fused levels, disc spaces of Cage dislodgement, and visual analogue scale (VAS) scores of low back pain and leg pain, Oswestry disability index (ODI), the segmental lordosis (SL) and disc height (DH) of the disc space of Cage dislodgement, and the lumbar lordosis (LL) before revision ( P>0.05). The operation time, intraoperative blood loss, hospital stay, and complications of the two groups were recorded and compared. The VAS scores of low back pain and leg pain were evaluated at 3 days, 3, 6, and 12 months after operation, and the ODI scores were evaluated at 3, 6, and 12 months after operation. The SL and DH of the disc space of Cage dislodgement and LL were measured at 12 months after operation and compared with those before operation. CT examination was performed at 12 months after operation, and the fusion of the disc space implanted with new Cage was judged by Bridwell grading standard. Results: The intraoperative blood loss in the OLIF group was significantly less than that in the PLIF group ( t=-12.425, P=0.000); there was no significant difference between the two groups in the operation time and hospital stay ( P>0.05). Both groups were followed up 12-30 months, with an average of 18 months. In the OLIF group, 2 patients (11.1%) had thigh numbness and 1 patient (5.6%) had hip flexor weakness after operation; 2 patients (9.1%) in the PLIF group had intraoperative dural sac tear. The other patients' incisions healed by first intention without early postoperative complications. There was no significant difference in the incidence of complications between the two groups ( χ2=0.519, P=0.642). The VAS scores of low back pain and leg pain, and the ODI score of the two groups at each time point after operation were significantly improved when compared with those before operation ( P0.05). At 12 months after operation, SL, LL, and DH in the two groups were significantly increased when compared with preoperative ones ( P0.05). CT examination at 12 months after operation showed that all the operated disc spaces achieved bony fusion. According to the Bridwell grading standard, 12 cases were grade Ⅰ and 6 cases were grade Ⅱ in the OLIF group, and 13 cases were grade Ⅰ and 9 cases were grade Ⅱ in the PLIF group; there was no significant difference between the two groups ( Z=-0.486, P=0.627). During follow-up, neither re-displacement or sinking of Cage, nor loosening or fracture of internal fixation occurred. Conclusion: OLIF and PLIF can achieve similar effectiveness in the treatment of Cage dislodgement after lumbar surgery. OLIF can further reduce intraoperative blood loss and restore the SL and DH of the disc space of Cage dislodgement better.
ABSTRACT
Objective: To investigate the effect and safety of tranexamic acid sequential rivaroxaban on perioperative blood loss and preventing thrombosis for elderly patients during lumbar interbody fusion (LIF) with a prospective randomized controlled study. Methods: Between April and October 2019, the elderly patients with lumbar degenerative diseases requiring LIF were included in the study, among which were 80 patients met the selection criteria. According to the antifibrinolysis and anticoagulation protocols, they were randomly divided into a tranexamic acid sequential rivaroxaban group (trial group) and a simple rivaroxaban group (control group) on average. Finally, 69 patients (35 in the trial group and 34 in the control group) were included for comparison. There was no significant difference in general data ( P>0.05) such as gender, age, body mass index, disease duration, diseased segment, type of disease, and preoperative hemoglobin between the two groups. The operation time, intraoperative blood loss, drainage within 3 days after operation, perioperative total blood loss, and proportion of blood transfusion patients were compared between the two groups, as well as postoperative venous thrombosis of lower extremities, pulmonary embolism, and bleeding-related complications. Results: The operations of the two groups completed successfully, and there was no significant difference in the operation time ( P>0.05); the intraoperative blood loss, drainage within 3 days after operation, and perioperative total blood loss in the trial group were significantly lower than those in the control group ( P<0.05). The proportion of blood transfusion patients in the trial group was 25.71% (9/35), which was significantly lower than that in the control group [52.94% (18/34)] ( χ2=5.368, P=0.021). Postoperative incision bleeding occurred in 4 cases of the trial group and 3 cases of the control group, and there was no significant difference in bleeding-related complications between the two groups ( P=1.000). There was 1 case of venous thrombosis of the lower extremities in each group after operation, and there was no significant difference in the incidence between the two groups ( P=1.000). Besides, no pulmonary embolism occurred in the two groups. Conclusion: Perioperative use of tranexamic acid sequential rivaroxaban in elderly LIF patients can effectively reduce the amount of blood loss and the proportion of blood transfusion patients without increasing the risk of postoperative thrombosis.
ABSTRACT
Objective: To summarize the research progress of ureteral injury in oblique lumbar interbody fusion (OLIF). Methods: The literature about incidence, clinical manifestations, diagnosis, and treatment of ureteral injury complications in OLIF was reviewed. Results: OLIF surgery poses a risk of ureteral injury because its surgical approach is anatomically adjacent to the left ureter. Ureteral injuries in OLIF are often insidious and have no specific clinical manifestations. CT urography is a common diagnostic method. The treatment of ureteral injury depends on a variety of factors such as the time of diagnosis, the location and degree of injury, and the treatment methods range from endoscopic treatment to replacement reconstruction. Conclusion: Surgeons should pay attention not to damage the ureter and find the abnormality in time during OLIF. High vigilance of abnormalities is conducive to the early diagnosis of ureteral injury. Furthermore, it is important to be familiar with ureter anatomy and gentle operation to prevent ureteral injury.
ABSTRACT
Background: This retrospective study was performed toassess the radiological and clinical outcome of patients whounderwent transforaminal lumbar interbody fusion (TLIF) withan interbody cage for spondylolisthesis.Methods: Forty five consecutive patients of spondylolisthesiswho underwent transforaminal lumbar interbody fusion (TLIF)during the period from July 2016 to June 2018 were reviewedretrospectively. Clinical data and radiological data werecollected and analysed. Twenty seven male and eighteenfemale patients underwent the TLIF procedure with a meanage of 48.6 years (24–66 years). The primary pathology was alytic listhesis in 28 patients and degenerative listhesis in 17.There was no multilevel fixation. Two cases were revisionsurgery. The mean blood loss was 290 ml and mean operativetime 160 minutes. No patient need to stay in ICU or HDU.Hospital stay was 4-5 days. Radiological outcome wasassessed by observing the presence of fusion mass at biplanarradiography whereas clinical outcomes were assessed bymeans of the Parker Visual Analog scale (VAS).Results wereclassified into three categories (excellent and good, fair, andpoor) using the Parker criteria. Pain was recorded by usingVisual Analog Scale.Results: There were no intra-operative complications. Twopatients developed neurological deficit in the form of partial footdrop. There were statistically significant improvements frompreoperative VAS to post-operative VAS. Fusion couldbe assessed in all patients. Anterior interbody fusion wasachieved in 78.3% of cases and posterior lateral fusion wasachieved in 69.6%.Four patients showed no fusion at the endof 6 months post operatively.Conclusions: Transforaminal lumbar interbody fusion is a safeand effective method to achieve circumferential fusion. It istechnically challenging and needs to be proficient in thetechnique to avoid catastrophic complications. Clinical scoringconfirmed that satisfactory overall outcome. Complicationsresulting from the procedure is uncommon and generally minorand transient.