Objective To summarize the basic research and the cl inical appl ication of biodegradable interbody fusion Cage. Methods Recent l iterature concerning biodegradable interbody fusion Cage at home and abroad was extensively reviewed, and current developments of the basic research and the cl inical appl ication of biodegradable interbody fusion Cage were investigated. Results Basic research showes that the stiffness of biodegradable interbody fusion Cage is lower than that of metall ic Cage, so it can enhance interbody fusion. As interbody fusion proceeded, biodegradable interbody fusion Cage degrades constantly, but the speed of degradation can not keep in parallel with that of fusion. In addition, the tissue response to degradation products is controversy. Cl inical appl ication showes that the biodegradable interbody fusion Cage can enhance interbody fusion and maintain disc space height. The short term results are good, however, the long term results need further observation. Conclusion Biodegradable interbody fusion Cage can effectively enhance interbody fusion.
ObjectiveTo analyze the relative position between lumbar plexus and access corridor of minimally invasive lateral transpsoas approach based on magnetic resonance imaging distribution of lumbar plexus by three dimensional reconstruction technique, so as to evaluate approach safety. MethodsThree-dimensional fast imaging employing steady-state acquisition sequences of lumbar spine were performed on 71 patients with lumbar degenerative diseases between July 2012 and January 2015. The axial image distance between the anterior edge of lumbar plexus and sagittal central perpendicular line (SCPL) of disc was determined using the distance formula at the mid-disc space from L1, 2 to L4, 5 level. SCPL was drawn perpendicularly to the sagittal plane of intervertebral disc and it passed through its central point, which is initial dilator trajectory for transpsoas approach. With respect to the SCPL of disc, the distance with a positive value indicated neural tissue posterior to it whereas anterior to it represented by a negative value. ResultsVarious branches of lumbar plexus which passed through the psoas major anterior to the SCPL of disc were identified in 42 (59.2%), 58 (81.7%), and 70 (98.6%) patients at L2, 3, L3, 4, and L4, 5 levels, respectively. It is possible to infer the presence of genitofemoral nerve in accordance with relevant anatomic research. A ventral migration of intrapsoas nerves is identified from L1, 2 to L4, 5 level. All differences between levels were statistically significant (P < 0.05). ConclusionWith respect to the SCPL of disc, a pass way of guide wire or a radiographic reference landmark to place working channel, lumbar plexus lie posterior to it from L1, 2 to L3, 4 level and shift anteriorly to it at L4, 5 level, while genitofemoral nerve locate anterior to the SCPL from L2, 3 to L4, 5 level. Neural retraction may take place during sequential dilation of working channel especially at L4, 5 level.
ObjectiveTo compare the effectiveness between anterior cervical Zero-profile interbody fusion device (Zero-P) and anterior cervical plate device (plate cage benezech, PCB) for cervical disease. MethodsBetween February 2011 and January 2013, 98 patients with cervical spondylosis who accorded with the inclusion criteria were treated with Zero-P in 49 cases (group A) and with PCB in 49 cases (group B). There was no significant difference in gender, age, disease type, disease duration, and disease segments between 2 groups (P>0.05). The Cobb angle, short-form 36 health survey scale (SF-36 scale), Japanese Orthopedic Association (JOA) score, postoperative dysphagia cases, neck disability index (NDI), and visual analogue scale (VAS) score were compared between 2 groups. ResultsThe operation time and intraoperative blood loss of group A were significantly less than those of group B (t=4.089, P=0.000;t=3.587, P=0.001). The patients were followed up 3-36 months (mean, 18.5 months). No loosening or breaking of internal fixation and bone absorption or collapse occurred in the other patients except 2 patients who suffered from screw loosening at 3 months after operation. Within 6 months after operation, dysphagia occurred in 8 cases (16.33%) of group A and in 13 cases (26.53%) of group B, showing significant difference (χ2=10.616, P=0.001). At last follow-up, JOA score, VAS score, NDI, SF-36 scale, and Cobb angle were significantly improved when compared with preoperative ones in 2 groups (P<0.05);the other indexes of group A were significantly better than those of group B (P<0.05) except SF-36 scale and Cobb angle (P>0.05). The excellent and good rate of JOA score was 81.63% in group A and 71.43% in group B, showing significant difference (χ2=4.346, P=0.037). ConclusionZero-P and PCB can get good results in treatment of cervical disease, but the Zero-P is better than PCB in reducing postoperative dysphagia because less wounds and strong stability.
ObjectiveTo study the anatomical characteristics of blood vessels in the lateral segment of the vertebral body through the surgical approach of oblique lumbar interbody fusion (OLIF) using MRI imaging, and evaluate its potential vascular safety zone. Methods The lumbar MRI data of 107 patients with low back and leg pain who met the selection criteria between October 2019 and November 2022 were retrospectively analyzed. The vascular emanation angles, vascular travel angles, and the length of vessels in the lateral segments of the left vertebral body of L1-L5, as well as the distance between the segmental vessels in different Moro junctions of the vertebral body and their distances from the edges of the vertebrae in the same sequence (bottom marked as I, top as S) were measured. The gap between the large abdominal vessels and the lateral vessels of the vertebral body was set as the lateral vascular safe zones of the lumbar spine, and the extent of the safe zones (namely the area between the vessels) was measured. The anterior 1/3 of the lumbar intervertebral disc was taken as the simulated puncture center, and the area with a diameter of 22 mm around it as the simulated channel area. The proportion of vessels in the channel was further counted. In addition, the proportions of segmental vessels at L5 without a clear travel and with an emanation angel less than 90° were calculated. Results Except for the differences in the vascular emanation angles between L4 and L5, the vascular travel angles between L1, L2 and L4, L5, and the length of vessels in the lateral segments of the vertebral body among L1-L4 were not significant (P>0.05), the differences in the vascular emanation angles, vascular travel angles, and the length of vessels between the rest segments were all significant (P<0.05). There was no significant difference in the distance between vessels of L1, L2 and L2, L3 at Moro Ⅰ-Ⅳ junctions (P>0.05), in L3, L4 and L4, L5 at Ⅱ and Ⅲ junction (P>0.05). There was no significant difference in the vascular distance of L2, L3 between Ⅱ, Ⅲ junction and Ⅲ, Ⅳ junction, and the vascular distance of L3, L4 between Ⅰ, Ⅱ junction and Ⅲ, Ⅳ junction (P>0.05). The vascular distance of the other adjacent vertebral bodies was significant different between different Moro junctions (P<0.05). Except that there was no significant difference in the distance between L2I and L3S at Ⅰ, Ⅱ junction, L3I and L4S at Ⅱ, Ⅲ junction, and L2I and L3S at Ⅲ, Ⅳ junction (P>0.05), there was significant difference of the vascular distance between the bottom of one segment and the top of the next in the other segments (P<0.05). Comparison between junctions: Except for the L3S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ junction, and L5S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ and Ⅲ, Ⅳ junctions had no significant difference (P>0.05), there were significant differences in the distance between the other segmental vessels and the vertebral edge of the same sequence in different Moro junctions (P<0.05). The overall proportion of vessels in the simulated channels was 40.19% (43/107), and the proportion of vessels in L1 (41.12%, 44/107) and L5 (18.69%, 20/107) was higher than that in the other segments. The proportion of vessels in the channel of Moro zone Ⅰ (46.73%, 50/107) and zone Ⅱ (32.71%, 35/107) was higher than that in the zone Ⅲ, while no segmental vessels in L1 and L2 were found in the channel of zone Ⅲ (χ2=74.950, P<0.001). Moreover, 26.17% (28/107) of the segmental vessels of lateral L5 showed no movement, and 27.10% (29/107) vascular emanation angles of lateral L5 were less than 90°. Conclusion L1 and L5 segmental vessels are most likely to be injured in Moro zones Ⅰ and Ⅱ, and the placement of OLIF channels in L4, 5 at Ⅲ, Ⅳ junction should be avoided. It is usually safe to place fixation pins at the vertebral body edge on the cephalic side of the intervertebral space, but it is safer to place them on the caudal side in L1, 2 (Ⅰ, Ⅱ junction), L3, 4 (Ⅲ, Ⅳ junction), and L4, 5 (Ⅱ, Ⅲ, Ⅳ junctions).
Spinal fusion is a standard operation for treating moderate and severe intervertebral disc diseases. In recent years, the proportion of three-dimensional printing interbody fusion cage in spinal fusion surgery has gradually increased. In this paper, the research progress of molding technology and materials used in three-dimensional printing interbody fusion cage at present is summarized. Then, according to structure layout, three-dimensional printing interbody fusion cages are classified into five types: solid-porous-solid (SPS) type, solid-porous-frame (SPF) type, frame-porous-frame (FPF) type, whole porous cage (WPC) type and others. The optimization process of three-dimensional printing interbody fusion cage and the advantages and disadvantages of each type are analyzed and summarized in depth. The clinical application of various types of 3D printed interbody fusion cage was introduced and summarized later. Lastly, combined with the latest research progress and achievements, the future research direction of three-dimensional printing interbody fusion cage in molding technology, application materials and coating materials is prospected in order to provide some reference for scholars engaged in interbody fusion cage research and application.
ObjectiveTo investigate the correlation between CT value and Cage subsidence in patients with lumbar degenerative disease treated with stand-alone oblique lumbar interbody fusion (OLIF). MethodsThe clinical data of 35 patients with lumbar degenerative diseases treated with stand-alone OLIF between February 2016 and October 2018 were retrospectively analyzed. There were 15 males and 20 females; the age ranged from 29 to 81 years, with an average of 58.4 years. There were 39 operative segments, including 32 cases of single-segment, 2 cases of double-segment, and 1 case of three-segment. Preoperative lumbar CT was used to measure the CT values of the axial position of L1 vertebral body, the axial and sagittal positions of L1-4 vertebral body, surgical segment, and the axial position of upper and lower vertebral bodies as the bone mineral density index, and the lowest T value was recorded by dual-energy X-ray absorptiometry. The visual analogue scale (VAS) and Oswestry disability index (ODI) scores were recorded before operation and at last follow-up. At last follow-up, the lumbar interbody fusion was evaluated by X-ray films of the lumbar spine and dynamic position; the lumbar lateral X-ray film was used to measure the subsidence of the Cage, and the patients were divided into subsidence group and nonsubsidence group. The univariate analysis on age, gender, body mass index, lowest T value, CT value of vertebral body, disease type, and surgical segment was performed to initially screen the influencing factors of Cage subsidence; further the logistic regression for multi-factor analysis was used to screen fusion independent risk factors for Cage subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were used to analyze the CT value and the lowest T value to predict the Cage subsidence. Spearman correlation analysis was used to determine the correlation between Cage subsidence and clinical results. Results All the 35 patients were followed up 27-58 months, with an average of 38.7 months. At last follow-up, the VAS and ODI scores were significantly decreased when compared with preoperative scores (t=32.850, P=0.000; t=31.731, P=0.000). No recurrent lower extremity radiculopathy occurred and no patient required revision surgery. Twenty-seven cases (77.1%) had no Cage subsidence (nonsubsidence group); 8 cases (22.9%) had at least radiographic evidence of Cage subsidence, the average distance of Cage subsidence was 2.2 mm (range, 1.1-4.2 mm) (subsidence group). At last follow-up, there was 1 case of fusion failure both in the subsidence group and the nonsubsidence group, there was no significant difference in the interbody fusion rate (96.3% vs. 87.5%) between two groups (P=0.410). Univariate analysis showed that the CT value of vertebral body (L1 axial position, L1-4 axial and sagittal positions, surgical segment, and upper and lower vertebral bodies axial positions) and the lowest T value were the influencing factors of Cage subsidence (P<0.05). According to ROC curve analysis, compared with AUC of the lowest T value [0.738, 95%CI (0.540, 0.936)], the AUC of the L1-4 axis CT value was 0.850 [95%CI (0.715, 0.984)], which could more effectively predict Cage subsidence. Multivariate analysis showed that the CT value of L1-4 axis was an independent risk factor for Cage subsidence (P<0.05). Conclusion The CT value measurement of the vertebral body based on lumbar spine CT before stand-alone OLIF can predict the Cage subsidence. Patients with low CT values of the lumbar spine have a higher risk of Cage subsidence. However, the Cage subsidence do not lead to adverse clinical results.
Objective To investigate the early effectiveness of Zero-profile interbody fusion system (Zero-P) in the treatment of cervical disc protrusion. Methods Between October 2010 and June 2012, 25 patients with cervical disc protrusion underwent anterior cervical discectomy and fusion (ACDF) using the Zero-P system. There were 15 males and 10 females, aged from 35 to 68 years (mean, 49 years). The disease duration was 3-26 months (mean, 10.5 months). Single segment was involved in all cases (2 cases in C3, 4, 5 cases in C4, 5, 11 cases in C5, 6, and 7 cases in C6, 7). The operation time and blood loss were recorded and analyzed. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, and neck disability index (NDI) were used to assess pain and nerve function improvement; the cervical Cobb angle was measured on the X-ray films before and after operation; according to Pitzen’s criteria, intervertebral fusion was evaluated. Results The operation was successful in 25 patients, with no severe complication. The average blood loss was 42.6 mL (range, 20-120 mL). The average operation time was 63.6 minutes (range, 45-90 minutes). Primary healing of incision was obtained in all cases; no injury of spinal cord and nerve root, cerebrospinal leakage, or deep infection occurred. The patients were followed up 6-23 months (mean, 14.5 months). No Cage subsidence and loosening, breaking, or pulling-out were observed. The symptoms and curvature of the cervical spine were obviously improved in all patients after operation. The VAS score, JOA score, NDI, and the cervical Cobb angle at 3 months and last follow-up showed significant differences when compared with preoperative ones (P lt; 0.05), but no significant difference was found between at 3 months and at last follow-up (P gt; 0.05). The interbody fusion was achieved in each operated segment of all patients according to Pitzen’s criteria. Conclusion The early effectiveness of ACDF with Zero-P system is satisfactory in treatment of cervical disc protrusion because it has the advantages of short operation time, less bleeding, good stability and restoration of the cervical alignment.
ObjectiveTo investigate the effectiveness of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) assisted with microscope in treatment of lumbar spondylolisthesis. MethodsBetween January 2011 and June 2012, 52 patients with lumbar spondylolisthesis underwent MI-TLIF assisted with microscope. There were 29 males and 23 females with an average age of 46 years (range, 32-67 years). The median disease duration was 3.2 years (range, 3 months to 6 years). There were 38 cases of lumbar isthmic spondylolisthesis and 14 cases of degenerative spondylolisthesis; 12 cases had stenosis secondary to lumbar spondylolisthesis. The affected segments were L4, 5 (29 cases) and L5, S1 (23 cases). According to the Meyerding evaluating system, 24 cases were classified as degree I and 28 cases as degree Ⅱ. The visual analogue scale (VAS) score and Oswestry disability index (ODI)were used for clinical assessment, and the clinical effects were also analyzed by Macnab criterion at last follow-up. The radiographic data were used to evaluate reduction of spondylolisthesis, including slipping degree, slipping angle, and intervertebral space height. The fusion rate was assessed by Suk criterion. ResultsThe operations were performed successfully in all patients. No dural tear or cerebrospinal fluid leakage occurred during operation. The average operation time was 105 minutes; the average intraoperative blood loss was 225 mL; the average postoperative drainage volume was 75 mL; and the average hospitalization days were 5.5 days. Superficial infection of incision occurred in 1 case and was cured after change dressing, and primary healing of incision was obtained in the others. All patients were followed up 12-26 months (mean, 18 months). No loosening, breakage, and displacement of pedicle screw and no Cage dislocation occurred by X-ray films after operation. The lumbar spondylolisthesis all got good correction. The three-dimensional CT showed continuous bone trabecula between centrums. The VAS score, ODI, and the slipping degree, slipping angle, and intervertebral space height were significantly improved at last follow-up when compared with preoperative ones (P<0.05). According to Macnab criterion at last follow-up, the results were excellent in 20 cases, good in 29 cases, and fair in 3 cases; the excellent and good rate was 94.2%. According to Suk criterion for fusion, 49 cases obtained complete fusion and 3 cases got possible fusion. ConclusionAs long as indications are seized, MI-TLIF assisted with microscope is safe and reliable for treatment of lumbar spondylolisthesis (Meyerding dergee I or Ⅱ), and it has the advantage of less injury, less blood loss, less complications, and definite short-term effectiveness.
Objective To investigate the effectiveness of surgical treatment for single-level degenerative lumbar instabil ity (DLI) by comparing traditional open transforaminal lumbar interbody fusion (TLIF) with minimally invasive TLIF. Methods Between March 2007 and May 2009，87 patients with single-level DLI were treated by traditional open TLIF (group A, n=45) and by minimally invasive TLIF (group B, n=42), respectively. There was no significant difference in gender, age, disease duration, segment level, combined diseases of lumbar spine, or the proportion of uni- and bilateral symptom between 2groups (P gt; 0.05). The indexes of surgical trauma，systemic inflammatory response, cl inical outcomes, and aravertebral muscle injury were compared between 2 groups. Results Operation was performed successfully in all patients. The patients were followed up 2.9 years on average in group A and 2.8 years on average in group B. The incision, blood loss, and postoperative drainage in group B were significantly less than those in group A (P lt; 0.05), but the operation time in group B was significantly longer than that in group A (P lt; 0.05). There were significant differences (P lt; 0.05) in C-reactive protein, leucocyte count, and creatine kinase MM between 2 groups at 24 hours postoperatively as well as in C-reactive protein at 6 days postoperatively; group B was superior to group A. At last follow-up, the Oswestry disabil ity index (ODI) and visual analogue score (VAS) were significantly improved when compared with the preoperative scores in 2 groups (P lt; 0.05). There were significant differences in ODI and back pain VAS score (P lt; 0.05), but no significant difference in leg pain VAS score (P gt; 0.05) between 2 groups. At last follow-up, no low back pain occurred in 8 and 18 cases, mild in 25 and 18 cases, moderate in 9 and 6 cases, and severe in 3 and 0 cases in groups A and B, respectively, showing that low back pain was significantly l ighter in group B than in group A (Z= —2.574, P=0.010). At last follow-up, the atrophy ratio of multifidus muscle was 37% ± 13% in group A and was 15% ± 7% in group B, showing significant difference (t=12.674, P=0.000). The multifidus muscle atrophy was rated as grade I in 18 and 44 sides, as grade II in 42 and 32 sides, and as grade III in 30 and 8 sides in groups A and B, respectively, showing significant difference (Z= — 4.947, P=0.000). Conclusion Both traditional open TLIF and minimally invasive TLIF are the effective treatments for single-level DLI. Minimally invasive TLIF has less surgical trauma, sl ighter postoperative systemic inflammatory response, less paravertebral muscle injury, and lower incidence of postoperative back pain, but it has longer operation time.
Objective To analyze the technical notes, effectiveness, and current issues of real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion. Methods Between April 2020 and October 2021, a total of 27 patients received real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion. There were 18 males and 9 females with an average age of 63.2 years (range, 48-84 years). There were 6 cases of lumbar spinal stenosis, 1 case of lumbar instability, 9 cases of lumbar spinal stenosis with instability, 3 cases of degenerative spondylolisthesis, 6 cases of isthmus spondylolisthesis, and 2 cases of recurrent lumbar disc herniation. All patients showed neurological symptoms before operation (ipsilateral symptom for 15 cases and bilateral symptom for 12 cases). The symptom duration was 1-300 months (median, 24 months). The operations were performed via transforaminal approach in 8 cases, trans-facet joint approach in 18 cases, and combined approaches in 1 case. A total of 32 levels were fused, including 23 single-level cases, 3 two-level cases, and 1 three-level case. Lumbar fusion segment was L2, 3 in 1 case, L3, 4 in 4 cases, L4, 5 in 20 cases, and L5, S1 in 7 cases. The operation time, intraoperative estimated blood loss (IEBL), and perioperative complications were recorded. The improvement of intervertebral space height at fusion level was measured, and the accuracy of percutaneous pedicle screw (PPS) and Cage placement was also evaluated based on CT images performed at 1 week postoperatively. Visual analogue scale (VAS) score for both low back pain and leg pain, Japanese Orthopaedic Association (JOA) score, and Oswestry disability index (ODI) were evaluated before operation, at 1 week postoperatively, and at last follow-up. Satisfaction to effectivenss were assessed by patients using modified MacNab criteria at last follow-up. Results The operation time was ranged from 255 to 805 minutes (mean, 424.9 minutes). IEBL was 150-290 mL (mean, 219.3 mL). All patients received follow-up with the duration from 4 to 22 months (mean, 12.4 months). At 1 week postoperatively and last follow-up, VAS scores of low back pain and leg pain, JOA score, and ODI were significantly improved when compared with those before operation (P<0.05). At last follow-up, the clinical indicators were similar in comparison with those at 1 week postoperatively (P>0.05). There were 26 patients and 1 patient who respectively ranked excellent and mild in terms of effectiveness according to the modified MacNab criteria, with the excellent and good rate of 96.3%. There was 1 patient who suffered from incomplete injury of L5 nerve root and partial neurological function recovered after 3-month conservative treatments. There were 118 implanted PPSs, and 116 of them were implanted under navigation. There were 33 Cages that were implanted under navigation. The accuracy of PPS and Cage placement was 99.1% and 97.0% respectively based on CT performed at 1 week postoperatively. The postoperative intervertebral space height was significantly increased in comparison with that before operation (P<0.05). During follow-up, mild Cage subsidence was observed in 1 patient, whereas no fixation loosing was found. Conclusion Real-time three-dimensional CT navigation-guided full-endoscopic lumbar interbody fusion has great safety and effectiveness with satisfactory preliminary clinical results. Design and further improvement of surgical equipment and instruments are expected to resolve the current technical difficulties.