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 investigate the early effctiveness of oblique lateral interbody fusion (OLIF) combined with pedicle screw fixation via small incision Wiltse approach for the treatment of lumbar spondylolisthesis.MethodsBetween January 2016 and December 2016, 21 patients with lumbar spondylolisthesis were treated with OLIF and pedicle screw fixation via small incision Wiltse approach. There were 9 males and 12 females, aged 57-73 years, with an average age of 64.5 years. The disease duration was 24-60 months, with an average of 34.6 months. All cases were spondylolisthesis at L4 (15 cases of degreeⅠ, 6 cases of degreeⅡ); 1 case had vertebral arch isthmus, and 20 cases had spinal stenosis. Japanese Orthopaedic Association (JOA) scoring system was used to evaluate the effectiveness before operation and at last follow-up. Before operation and at 2 days after operation, anteroposterior and lateral X-ray films and CT were taken to measure the sagittal diameter and cross-sectional area of the spinal canal, and calculate the intervertebral height and degree of spondylolisthesis. At 6 months after operation, the intervertebral fusion was evaluated by CT.ResultsThe operation time was 120-180 minutes, with an average of 155 minutes; the intraoperative blood loss was 100-340 mL, with an average of 225.5 mL. One patient had slight injury of lower endplate, 1 patient had numbness of thigh and weakness of hip flexion after operation, 1 patient had sympathetic nerve trunk injury. All the cases were followed up 12-18 months, with an average of 14.3 months. The symptoms of low back pain, leg pain, and numbness of lower limbs significantly relieved after operation, and there was no complication such as protrusion of fusion cage, screw breakage, and endplate collapse. At 2 days after operation, the intervertebral height, degree of spondylolisthesis, sagittal diameter of spinal canal, and cross-sectional area of spinal canal significantly improved compared with preoperative ones (P<0.05). At 6 months after operation, CT showed that 1 patient had poor interbody fusion (grade Ⅲ), the other 20 patients had good interbody fusion (grade Ⅰ and Ⅱ), and the interbody fusion rate was 95.2%. At last follow-up, JOA score of lumbar spine significantly increased compared with that before operation (t=24.980, P=0.000).ConclusionOLIF combined with pedicle screw fixation via small incision Wiltse approach for the lumbar spondylolisthesis has minimally invasive features, such as less trauma, fewer complications, and higher intervertebral fusion rate. It is a safe and effective method.
Objective To compare the effectiveness between three-dimensional (3D) printed porous titanium alloy cage (3D Cage) and poly-ether-ether-ketone cage (PEEK Cage) in the posterior lumbar interbody fusion (PLIF). Methods A total of 66 patients who were scheduled to undergo PLIF between January 2018 and June 2019 were selected as the research subjects, and were divided into the trial group (implantation of 3D Cage, n=33) and the control group (implantation of PEEK Cage, n=33) according to the random number table method. Among them, 1 case in the trial group did not complete the follow-up exclusion study, and finally 32 cases in the trial group and 33 cases in the control group were included in the statistical analysis. There was no significant difference in gender, age, etiology, disease duration, surgical segment, and preoperative Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The operation time, intraoperative blood loss, complications, JOA score, intervertebral height loss, and interbody fusion were recorded and compared between the two groups. Results The operations of two groups were completed successfully. There was 1 case of dural rupture complicated with cerebrospinal fluid leakage during operation in the trial group, and no complication occurred in the other patients of the two groups. All incisions healed by first intention. There was no significant difference in operation time and intraoperative blood loss between groups (P>0.05). All patients were followed up 12-24 months (mean, 16.7 months). The JOA scores at 1 year after operation in both groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between groups (P>0.05) in the difference between pre- and post-operation and the improvement rate of JOA score at 1 year after operation. X-ray film reexamination showed that there was no screw loosening, screw rod fracture, Cage collapse, or immune rejection in the two groups during follow-up. At 3 months and 1 year after operation, the rate of intervertebral height loss was significantly lower in the trial group than in the control group (P<0.05). At 3 and 6 months after operation, the interbody fusion rating of trial group was significantly better in the trial group than in the control group (P<0.05); and at 1 year after operation, there was no significant difference between groups (P>0.05). ConclusionThere is no significant difference between 3D Cage and PEEK Cage in PLIF, in terms of operation time, intraoperative blood loss, complications, postoperative neurological recovery, and final intervertebral fusion. But the former can effectively reduce vertebral body subsidence and accelerate intervertebral fusion.
ObjectiveTo compare the biomechanical differences between the kidney-shaped nano-hydroxyapatite/polyamide 66 (n-HA/PA66) Cage and the bullet-shaped n-HA/PA66 Cage. MethodsL2-L5 spinal specimens were selected from 10 adult male pigs. L2, L3 and L4, L5 served as a motor unit respectively, 20 motor units altogether. They were divided into 4 groups (n=5):no treatment was given as control group (group A); nucleus pulposus resection was performed (group B); bullet-shaped Cage (group C), and kidney-shaped Cage (group D) were used in transforaminal lumbar interbody fusion (TLIF) through left intervertebral foramen and supplemented by posterior pedicle screw fixation. The intervertebral height (IH) and the position of Cages were observed on the X-ray films. The range of motion (ROM) was measured. ResultsThere was no significant difference in the preoperative IH among 4 groups (F=0.166, P=0.917). No significant change was found in IH between at pre- and post-operation in group B (P>0.05); it increased after operation in groups C and D, but difference was not statistically significant (P>0.05). There was no significant difference in the postoperative IH among groups B, C, and D (P>0.05). The distance from Cage to the left margin was (3.06±0.51) mm in group C (close to the left) and (5.68±0.69) mm in group D (close to the middle), showing significant difference (t=6.787, P=0.000). The ROM in all directions were significantly lower in groups C and D than in groups A and B (P<0.05), and in group A than in group B (P<0.05). The right bending and compression ROM of group C were significantly higher than those of group D (P<0.05), but no statistically significant difference was found in the other direction ROM (P>0.05). ConclusionThe bullet-shaped and kidney-shaped Cages have similar results in restoring IH and maintaining the stability of the spine assisted by internal fixation. Kidney-shaped Cage is more stable than bullet-shaped Cage in the axial compression and the bending load opposite implant, it can be placed in the middle and back of the vertebral body more ideally.
Objective To evaluate the safety and effectiveness of anterior cervical discectomy and fusion (ACDF) by using zero-profile anchored cage (ZAC) in treatment of consecutive three-level cervical spondylosis, by comparing with plate-cage construct (PCC). Methods A clinical data of 65 patients with cervical spondylosis admitted between January 2020 and December 2022 and met the selection criteria was retrospectively analyzed. During consecutive three-level ACDF, 35 patients were fixed with ZAC (ZAC group) and 30 patients with PCC (PCC group). There was no significant difference in baseline data between the two groups (P>0.05), including gender, age, body mass index, surgical segment, preoperative Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), visual analogue scale (VAS) score, prevertebral soft tissue thickness (PSTT), cervical lordosis, and surgical segmental angle. The operation time, intraoperative blood loss, hospital stay, clinical indicators (JOA score, NDI, VAS score), and radiological indicators (cervical lordosis, surgical segmental angle, implant subsidence, surgical segment fusion, and adjacent segment degeneration), and the postoperative complications [swelling of the neck (PSTT), dysphagia] were recorded and compared between the two groups. Results Patients in both groups were followed up 24-39 months. There was no significant difference in follow-up duration between the two groups (P>0.05). The operation time and intraoperative blood loss were lower in ZAC group than in PCC group, and the length of hospital stay was longer, but there was no significant difference (P>0.05). At each time point after operation, both groups showed significant improvements in JOA score, VAS score, and NDI compared with preoperative scores (P<0.05), but there was no significant difference between the two groups at each time point after operation (P>0.05). Both groups showed an increase in PSTT at 3 days and 3, 6 months after operation compared to preoperative levels (P<0.05), but returned to preoperative levels at last follow-up (P>0.05). The PSTT at 3 days and 3 months after operation were significantly lower in ZAC group than in PCC group (P<0.05), and there was no significant difference between the two groups at 6 months and at last follow-up (P>0.05). The incidences of dysphagia at 3 days and 3 months were significantly lower in ZAC group than in PCC group (P<0.05), while no significant difference was observed at 6 months and last follow-up between the two groups (P>0.05). There was no postoperative complication in both groups including hoarseness, esophageal injury, cough, or hematoma. Both groups showed improvement in cervical lordosis and surgical segmental angle compared to preoperative levels, with a trend of loss during follow-up. The cervical lordosis loss and surgical segmental angle loss were significantly more in the ZAC group than in PCC group (P<0.05). The incidence of implante subsidence was significantly higher in ZAC group than in PCC group (P<0.05). There was no significant difference between the ZAC group and PCC group in the incidences of surgical segment fusion and adjacent segment degeneration (P>0.05). ConclusionIn consecutive three-level ACDF, both ZAC and PCC can achieve satisfactory effectiveness. The former can reduce the incidence of postoperative dysphagia, while the latter can better maintain cervical curvature and reduce the incidence of implant subsidence.
Objective To review the research progress of Modic changes and its influence on lumbar interbody fusion. Methods The domestic and foreign literature related to Modic changes and its influence on lumbar interbody fusion was extensively reviewed. The etiology of Modic changes was summarized, and the treatment measures of Modic changes on lumbar interbody fusion were discussed. Results The etiology of Modic changes is not clear, which may be related to mechanical factors, autoimmune factors, low toxic infection factors, and genetic factors. Modic changes may lead to fusion failure and cage subsidence after lumbar interbody fusion. Preoperative evaluation of endplate sclerosis, reduction of iatrogenic endplate injury, fine operating of intervertebral space, management of osteoporosis, and selection of appropriate cage can prevent or reduce fusion failure or cage subsidence. Conclusion Modic changes may lead to fusion failure and cage subsidence after lumbar interbody fusion, and active perioperative intervention of Modic changes is helpful to improve the clinical prognosis.
Objective To compare the effectiveness of a zero-profile three-dimensiaonal (3D)-printed microporous titanium alloy Cage and a conventional titanium plate combined with a polyether-ether-ketone (PEEK)-Cage in the treatment of single-segment cervical spondylotic myelopathy (CSM) by anterior cervical discectomy and fusion (ACDF). Methods The clinical data of 83 patients with single-segment CSM treated with ACDF between January 2022 and January 2023 were retrospectively analyzed, and they were divided into 3D-ZP group (35 cases, using zero-profile 3D-printed microporous titanium alloy Cage) and CP group (48 cases, using titanium plate in combination with PEEK-Cage). There was no significant difference in gender, age, disease duration, surgical intervertebral space, and preoperative Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score, neck disability index (NDI), vertebral height at the fusion segment, Cobb angle, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stay, complications, interbody fusion, and prosthesis subsidence were recorded and compared between the two groups. VAS score, NDI, and JOA score were used to evaluate the improvement of pain and function before operation, at 3 months after operation, and at last follow-up, and the vertebral height at the fusion segment and Cobb angle were measured by imaging. The degree of dysphagia was assessed by the Bazaz dysphagia scale at 1 week and at last follow-up. Results The operation was successfully completed in all the 83 patients. There was no significant difference in intraoperative blood loss and hospital stay between the two groups (P>0.05), but the operation time in the 3D-ZP group was significantly shorter than that in the CP group (P<0.05). Patients in both groups were followed up 24-35 months, with an average of 25.3 months, and there was no significant difference in the follow-up time between the two groups (P>0.05). The incidence and grade of dysphagia in CP group were significantly higher than those in 3D-ZP group at 1 week after operation and at last follow-up (P<0.05). There was no dysphagia in 3D-ZP group at last follow-up. There was no complication such as implant breakage or displacement in both groups. The intervertebral fusion rates of 3D-ZP group and CP group were 65.71% (23/35) and 60.42% (29/48) respectively at 3 months after operation, and there was no significant difference between the two groups [OR (95%CI)=1.256 (0.507, 3.109), P=0.622]. The JOA score, VAS score, and NDI significantly improved in the 3D-ZP group at 3 months and at last follow-up when compared with preoperative ones (P<0.05), but there was no significant difference between the two groups (P>0.05). There was no significant difference in the improvement rate of JOA between the two groups at last follow-up (P>0.05). At 3 months after operation and at last follow-up, the vertebral height at the fusion segment and Cobb angle significantly improved in both groups, and the two indexes in 3D-ZP group were significantly better than those in CP group (P<0.05). At last follow-up, the incidence of prosthesis subsidence in 3D-ZP group (8.57%) was significantly lower than that in CP group (29.16%) (P<0.05). ConclusionThe application of zero-profile 3D-printed Cage and titanium plate combined with PEEK-Cage in single-segment ACDF can both reconstruct the stability of cervical spine and achieve good effectiveness. Compared with the latter, the application of the former in ACDF can shorten the operation time, reduce the incidence of prosthesis subsidence, and reduce the incidence of dysphagia.
Objective To assess the clinical application value of tranforaminal unilateral approach for bilateral decompression by comparing the short-term effectiveness of bilateral decompression via unilateral approach of intervertebral foramen with via small surgical incision of bilateral spinous process in lumbar interbody fusion for the treatment of lumbar spinal stenosis. Methods Between July 2014 and June 2015, 48 patients with lumbar spinal stenosis underwent decompression and internal fixation by unilateral approach in 24 cases (trial group) and by bilateral small incision approach in 24 cases (control group). There was no significant difference in gender, age, disease duration, disease type, involved segment, combined medical diseases, preoperative level of creatine phosphokinase (CPK), the visual analogue scale (VAS), and Oswestry disability index (ODI) between 2 groups (P>0.05). The operation time, intraoperative blood loss, postoperative drainage, hospitalization time, and the incidence of complications were recorded. The CPK levels were evaluated at 1, 3, and 7 days after operation. VAS score and ODI were used to evaluate the effectiveness, and lumbar X-ray film or CT scanning to determine the intervertebral bony fusion. Results There was no significant difference in operation time, intraoperative blood loss, and hospitalization time between 2 groups (P>0.05), but significant difference was found in postoperative drainage (t=5.547,P=0.000). At 1 day after operation, the level of CPK in the trial group was significantly lower than that in the control group (t=3.129,P=0.005), but there was no significant difference at 3 and 7 days after operation between 2 groups (P>0.05). The patients were followed up 12-24 months (mean, 17 months). All the wounds healed primarily. Heart failure occurred in 1 case of the trial group, and cerebrospinal fluid leakage and pulmonary infection, and nerve root injury occurred in 1 case of the control group respectively. There was no significant difference in the incidence of complications between 2 groups (χ2=0.273,P=0.602). The interbody fusion rate was 95.8% (23/24) in the trial group and was 91.7% (22/24) in the control group, showing no significant difference (χ2=0.356,P=0.551). No cage sink, dislocation or plate and screw loosening and breakage was found in 2 groups. No adjacent segment degeneration occurred during the follow-up, and there was no change of scoliosis and lumbar sagittal curvature. At 3, 6, and 12 months after operation, the VAS score and ODI were significantly improved when compared with the preoperative scores in 2 groups (P<0.05), and the VAS score and ODI of the trial group were significantly better than those of control group (P<0.05). Conclusion The bilateral decompression via unilateral approach of intervertebral foramen and small surgical incision of bilateral spinous process in lumbar interbody fusion have satisfactory efficacy for the treatment of lumbar spinal stenosis, but the tranforaminal unilateral approach has the advantages of less trauma, avoidance of bilateral muscle stripping and soft paraspinal muscle injury, retention of posterior spinal structure, faster postoperative recovery, shorter hospital stay and good short-term effectiveness.