Project description:Objective: Pedicle screw fixation is a common technique used in posterior lumbar interbody fusion (PLIF) surgery for lumbar disorders. During operation, rod contouring is often subjective and not satisfactory, but only few studies focused on the rod-contouring issue previously. The aim of the study was to explore the effect of the rod contouring on the single-segment PLIF by the finite element (FE) method and retrospective study. Methods: A FE model of the lumbosacral vertebrae was first reconstructed, and subsequently single-segmental (L4/5) PLIF surgeries with four rod curvatures (RCs) were simulated. Herein, three RCs were designed by referring to centroid, Cobb, and posterior tangent methods applied in the lumbar lordosis measurement, and zero RC indicating straight rods was included as well. Clinical data of patients subjected to L4/5 segmental PLIF were also analyzed to verify the correlation between RCs and clinical outcome. Results: No difference was observed among the four RC models in the range of motion (ROM), intersegmental rotation angle (IRA), and intradiscal pressure (IDP) under four actions. The posterior tangent model had less maximum stress in fixation (MSF) in flexion, extension, and axial rotation than the other RC models. Patients with favorable prognosis had larger RC and positive RC minus posterior tangent angle (RC-PTA) of fused segments with respect to those who had poor prognosis and received revision surgery. Conclusion: All RC models had similar biomechanical behaviors under four actions. The posterior tangent-based RC model was superior in fixation stress distribution compared to centroid, Cobb, and straight models. The retrospective study demonstrated that moderate RC and positive RC-PTA were associated with better postoperative results.
Project description:BackgroundAdvances in modern spinal fusion techniques have allowed for less peri-operative morbidity and more rapid recovery from surgery. The addition of endoscopy to minimally invasive surgery (MIS) fusion techniques represents the latest progression of efforts to minimize the impact of surgical intervention.TechniqueMIS transforaminal lumbar interbody fusion (TLIF) is performed endoscopically through a sub-centimeter working portal. Patients undergo light conscious sedation and remain awake to facilitate feedback with the surgeon and enhance post-operative recovery.ResultsPreviously reported results of the first 100 cases performed by the senior author at a single institution are summarized. This cohort has been characterized by brief post-operative length of stay, low complication profile, and marked improvement in patient-reported outcomes scores, with no cases of pseudarthrosis at 1-year follow up.ConclusionsThe latest technical considerations and adaptations of a novel technique for endoscopic MIS spinal fusion without general anesthesia are described. A refined surgical technique and anesthetic protocol are presented in detail with recommendations for the successful implementation and performance of the procedure.
Project description:PurposeTo relate the progress of vertebral segmental stability after interbody fusion surgery with radiological assessment of spinal fusion.MethodsTwenty goats received double-level interbody fusion and were followed for a period of 3, 6 and 12 months. After killing, interbody fusion was assessed radiographically by two independent observers. Subsequently, the lumbar spines were subjected to four-point bending and rotational deformation, assessed with an optoelectronic 3D movement registration system. In addition, four caprine lumbar spines were analysed in both the native situation and after the insertion of a cage device, as to mimic the direct post-surgical situation. The range of motion (ROM) in flexion/extension, lateral bending and axial rotation was analysed ex vivo using a multi-segment testing system.ResultsSignificant reduction in ROM in the operated segments was already achieved with moderate bone ingrowth in flexion/extension (71 % reduction in ROM) and with only limited bone ingrowth in lateral bending (71 % reduction in ROM) compared to the post-surgical situation. The presence of a sentinel sign always resulted in a stable vertebral segment in both flexion/extension and lateral bending. For axial rotation, the ROM was already limited in both native and cage inserted situations, resulting in non-significant differences for all radiographic scores.DiscussionIn vivo vertebral segment stability, defined as a significant reduction in ROM, is achieved in an early stage of spinal fusion, well before a radiological bony fusion between the vertebrae can be observed. Therefore, plain radiography underestimates vertebral segment stability.
Project description:Oblique lateral lumbar interbody fusion (OLLIF) is a novel operation for fusions of the lumbar spine from T12-S1. In OLLIF, the disk is approached from an oblique lateral angle guided by electrophysiological monitoring and biplanar fluoroscopy; the disk space is accessed through Kambin's triangle. We present perioperative, clinical, patient-reported and radiological outcomes from a series of 303 OLLIF procedures on 568 levels performed by the same surgeon. For a single-level OLLIF, mean surgery time was 56.6 ± 37.7 minutes, with a blood loss of 42.2 ± 31.1 mL, fluoroscopy time of 198.8 ± 87.2 seconds and a hospital stay of 2.2 ± 1.7 days. At the one-year follow-up, 10-point pain scale scores improved from 8.6 ± 1.3 to 4.1 ± 3.0 (p < 0.001). Total Oswestry disability index score improved from 56.6% ± 15.3% to 38.6% ± 21.4% (p < 0.001). At the one-year follow-up, 15 (5%) patients had mild nerve root irritation defined as sensory symptoms and motor weakness better than 4/5. Only one patient had neuropraxia due to weakness (3/5). There was one case (0.3%) of superficial wound infection and one case of bleeding into the psoas major. Reoperation within one year was performed for 14 (4.7%) patients. Interbody fusion was achieved in 98.7% of levels. While OLLIF has previously been described, this study is the first to present clinical, patient-reported, and radiological outcomes of OLLIF. Review of the literature shows that OLLIF produces perioperative outcomes, complication rates, and fusion rates that compare favorably with similar procedures. We establish that OLLIF is a safe, efficient and efficacious procedure for fusions of the lumbar spine.
Project description:BackgroundThe use of interbody cages as an adjunct to lumbar spinal fusion remains an important technique to enhance segmental stability, promote solid arthrodesis, maintain neuroforaminal decompression, and preserve/improve segmental lordosis. Appropriate segmental lumbar lordosis and sagittal balance is well-known to be critical for long-term patient outcomes. This study sought to evaluate the radiographic and clinical results of TLIF in patients using an articulating, expandable cage. Primary endpoint was clinical and radiographic outcomes, including complications, at 12 and 24 months.MethodsA total of 37 patients underwent open single-level or 2-level TLIF by a single surgeon using an expandable cage with concomitant bilateral pedicle screws and posterolateral arthrodesis. Clinical outcomes included ODI and VAS for back and legs. Radiographic outcomes included pelvic incidence and tilt, lumbar and segmental lordoses, and disc height at the operative level(s). All outcomes were collected at baseline, 2-weeks, 6-weeks, 3-months, 6-months, 12-months, and 24-months postop.ResultsA total of 28 patients were available for analysis. Nine patients failed to follow-up at 24 months. Mean ODI scores showed significant improvement, from pre-to-postoperative at 24 months (55%; p<.0001). VAS for back and legs was significantly lower at 24 months on average by 72 and 79%, respectively (p<.0001 for both). Both segmental and lumbar lordoses significantly improved by 5.3° and 4.2° (p<.0001 and p=.049), respectively. Average disc height improved by 49% or 6.1 mm (p<.001). No device-related complications nor instances of measured subsidence. One patient had a superficial infection, and another had an intraoperatively repaired incidental durotomy.ConclusionsThe use of an expandable cage contributed to improvement in both segmental and lumbar lordosis with no reported complications at 24-month follow-up. All clinical measures significantly improved as well. The expandable cage design represents an effective and safe option to increase cage size and allow significant segmental lordosis correction.
Project description:Objective:Endoscopic surgeries have been attempted in the field of lumbar decompression and fusion surgery in the past decade. Percutaneous endoscopic lumbar interbody fusion (PELIF) is a new-emerging technique taking advantages of an anatomical (Kambin's triangle) to achieve simultaneous decompression and fusion under endoscopic visualization. The purpose of this study is to evaluate the feasibility and safety of PELIF technique with general anesthesia and neuromonitoring. Methods:The authors present the details of PELIF technique with general anesthesia and neuromonitoring. The first 7 consecutive patients treated with minimum of 2 year's follow-up were included. Clinical outcomes were assessed by visual analog scale (VAS) for back and leg pain, Oswestry Disability Index (ODI) scores, and the Short Form-36 health survey questionnaire (SF-36) in the immediate preoperative period and during the follow-up period. Results:All patients underwent single-level PELIF surgery successfully and without conversion to open surgery. The average age was 56.0±13.0 years. All patients had Grade I degenerative/isthmic spondylolisthesis and 4 patients coexisted with disc herniation. The mean operative time was 167.5±30.9 minutes, and intraoperative blood loss was 70.0±24.5 ml. Postoperative drainage volume was 24.5±18.3 ml. The differences in the VAS scores for low back pain and leg pain between preoperative and follow-up were significant (P<0.05). The SF-36 Physical Component Summary (PCS) improved from 38.83±4.17 to 55.67±2.58 (P<0.001). The SF-36 Mental Component Summary (MCS) improved from 43.83±3.13 to 57.50±5.36 (P=0.001). The ODI score improvement rate was 33.7±3.7 %. All cases demonstrated radiopaque graft in the intervertebral disc space consistent with solid arthrodesis. Conclusions:PELIF technique seems to be a promising surgical technique for selected appropriate patients, with the minimal invasive advantages in decreased blood, shortage of ambulation time, and hospital stay, compared with MIS-TLIF. Because of limited Kambin's triangle space and the exiting nerve root nearby, PELIF is still a challenging technique. Future advancement and development in instrument and cage design are vital for application and popularization of this technique. Prospective, randomized, controlled studies with large sample size on PELIF technique are still needed to prove its safety, efficacy, and minimal invasive advantages.
Project description:Minimally invasive techniques for transforaminal lumbar interbody fusion (MIS-TLIF) are advantageous because they allow for sufficient surgical exposure and fewer complications through a smaller incision than conventional TLIF. It could be difficult to maintain minimally invasive spine surgery following the unexpected complications after MIS-TLIF. Because MIS-TLIF is usually done via a paramedian small incision with posterior fusion using screws and rods, visualization of the surgical field is limited, and it is difficult to directly assess the neural structure without removing instrumentation. Unilateral biportal endoscopic decompression (UBE) is a rapidly growing surgical method using two 1-cm incisions that are 2 to 3 cm apart. We would like to suggest UBE as an option for immediate reoperation after MIS-TLIF because it has the advantages of targeting pathologic regions and a wide field of visualization through small wounds. The operation is independent of the existing incision from MIS-TLIF, enabling immediate revision surgery without the removal of the screws and rods. UBE has the advantages of targeting specific surgical regions and providing a wide visualization of the operation field through small incisions. UBE can be very useful for discectomy or decompression surgery as well as in immediate reoperation after MIS-TLIF.
Project description:BACKGROUND:In the current surgical therapeutic regimen for the degenerative lumbar disease, both oblique lateral interbody fusion (OLIF) and lateral lumbar interbody fusion (LLIF) are gradually accepted. Thus, the objective of this study is to compare the radiographic and clinical outcomes of OLIF and LLIF for the degenerative lumbar disease. METHODS:We conducted an exhaustive literature search of MEDLINE, EMBASE, and the Cochrane Library to find the relevant studies about OLIF and LLIF for the degenerative lumbar disease. Random-effects model was performed to pool the outcomes about disc height (DH), fusion, operative blood loss, operative time, length of hospital stays, complications, visual analog scale (VAS), and Oswestry disability index (ODI). RESULTS:56 studies were included in this study. The two groups of patients had similar changes in terms of DH, operative blood loss, operative time, hospital stay and the fusion rate (over 90%). The OLIF group showed slightly better VAS and ODI scores improvement. The incidence of perioperative complications of OLIF and LLIF was 26.7 and 27.8% respectively. Higher rates of nerve injury and psoas weakness (21.2%) were reported for LLIF, while higher rates of cage subsidence (5.1%), endplate damage (5.2%) and vascular injury (1.7%) were reported for OLIF. CONCLUSIONS:The two groups are similar in terms of radiographic outcomes, operative blood loss, operative time and the length of hospital stay. The OLIF group shows advantages in VAS and ODI scores improvement. Though the incidence of perioperative complications of OLIF and LLIF is similar, the incidence of main complications is significantly different.
Project description:BackgroundA series of full-endoscopic lumbar interbody fusions have been reported, but special fusion cages or operating instruments are often needed, and there are many complications in the operation and the learning curve is long. We have used a single portal endoscopic system for lumbar interbody fusion in a novel posterolateral transarticular approach, which will take advantage of the incision for pedicle screw insertion and avoid nerve root damage by using a transparent plastic working tube. The purpose of this study was to present the surgical technique of full endoscopic posterolateral transarticular lumbar interbody fusion (FE-PTLIF) and to analyze the preliminary clinical results.MethodsA total of 39 patients (17 men and 22 women; mean age [x̅ ± s] 55.2 ± 12.2 years) have been enrolled in this retrospective study between March 2019 and January 2021 in the Second Affiliated Hospital of Chongqing Medical University. All patients were treated with full endoscopic lumbar interbody fusion via posterolateral transarticular approach with a transparent plastic working tube. Demographic characteristics, diagnosis, operative time, and estimated blood loss were evaluated. Intraoperative photo and perioperative imaging were recorded. The preoperative and postoperative clinical data were collected for statistical analysis.ResultsThe preliminary clinical follow-up data achieved good results. No patients had serious postoperative complications and none of these patients required revision surgery during the perioperative or follow-up period. We compared the visual analogue scale and Oswestry disability index scores before and after surgery. The differences were statistically significant (P < 0.05). The mean total blood loss (including drainage blood) was 54.4 ± 20.3 ml. The mean operative time was 130.5 ± 23.8 min. At the last follow-up, the fusion rate of the lumbar intervertebral space was 100%.ConclusionsThis novel posterolateral transarticular approach and transparent plastic working tube can reduce the difficulty of the operation, so that the conventional intervertebral fusion cage [bullet-shaped polyetheretherketone (PEEK) nonexpandable fusion cage] and surgical instruments can be used in the full endoscopic lumbar intervertebral fusion surgery, which can reduce the cost and improve the efficiency of the operation.
Project description:ObjectiveLateral lumbar interbody fusion (LLIF) is a highly useful lumbar fusion surgical technique for degenerative spinal disease. However, many complications have already been reported. The purpose of this study is to report the concept, surgical technique, and clinical results of the first 70 consecutive cases treated with a safer and minimally invasive endoscopic-assisted LLIF (ELLIF).MethodsThis retrospective study included 70 cases involving 106 segments in which ELLIF was used to treat degenerative spinal disease. We examined the clinical progress, complications and analyzed radiographic images. Regarding the fusion rate, 49 cases involving 72 segments whose follow-up period was more than 7 months were evaluated.ResultsThe mean of preoperative Numerical Rating Scale (NRS) was 7.0 and postoperative NRS was 1.4. Postoperative NRS had a significant correlation with the number of fusion segments (p = 0.028). The mean of preoperative disc space height, foraminal height, sagittal rotation angle, whole lumbar lordosis and sagittal translation distance were 3.3 mm, 14.3 mm, 2.4°, 9.7°, and 3.2 mm, respectively. Postoperative values were 9.4 mm, 17.9 mm, -4.9°, 36.3°, and 0.7 mm. The fusion rate was 79.2%. Complications included, transient psoas muscle weakness 1, sensory disturbance in the thigh 2, retroperitoneal injury 1, postoperative ileus possibly involving a retroperitoneal injury 1, and cage migration 4.ConclusionUsing the ELLIF in the degenerative spinal disease, we obtained good radiological reduction and good clinical results. Our study confirms that ELLIF is safer and provides better results for degenerative spinal disease. However, the issue of cage migration remains to be resolved.