Comparison of the effectiveness and safety of bioactive glass ceramic to allograft bone for anterior cervical discectomy and fusion with anterior plate fixation.

Recently, a bioactive glass ceramic (BGC) has been developed for use as intervertebral cages for anterior cervical discectomy and fusion (ACDF). However, the effectiveness and safety of BGC cages remain to be evaluated. We completed a retrospective comparison of the radiological and clinical outcomes of 36 patients (52 levels) who underwent ACDF with a BGC cage and 35 patients (54 levels) using allograft bone. The following variables were compared between the two groups: the visual analog (VAS) neck and arm pain score and the neck disability index (NDI), measured before surgery and 1 year after; the change in Cobb's angle, between the C2 and C7 vertebrae, the global sagittal angle, and disc height compared from before surgery to 1 year after; and the rate of spinal fusion and cage subsidence at 1 and 2 years after surgery. The VAS and NDI scores were not different between the two groups. Similarly, the spinal fusion rate was not different between the BGC and allograft bone group at 1 year (73% and 87%, respectively; p = 0.07) and 2 years (94% and 91%, respectively; p = 0.54) after surgery. However, the rate of cage subsidence was higher in the allograft bone (43%) than the BGC (19%) group (p = 0.03), as was the rate of instrument-related failure (p = 0.028), with a specifically higher incidence of implant fracture or failure in the allograft bone group (p = 0.025). Overall, our findings indicate that BGC cages provide a feasible and safe alternative to allograft bone for ACDF.

Patterns of short-term and long-term surgical outcomes and prognostic factors for cervical ossification of the posterior longitudinal ligament between anterior cervical corpectomy and fusion and posterior laminoplasty.

To compare short-term and long-term surgical outcome patterns between anterior cervical corpectomy and fusion (ACCF) and laminoplasty (LP) in patients diagnosed with cervical ossification of the posterior longitudinal ligament (OPLL) and identify factors affecting surgical outcomes based on follow-up duration. During short-term follow-up period, surgical outcomes between ACCF and LP were similar. However, there were several reports that long-term surgical outcomes were superior in the ACCF compared with LP. Surgical outcomes between ACCF and LP according to follow-up period changed. This study enrolled 70 patients who underwent ACCF and 63 patients who underwent LP between 2005 and 2012. Patterns of surgical outcomes were analyzed in accordance with surgical procedures. Furthermore, these patients were divided into two subgroups in respect of follow-up duration: the short-term group (less than 48 months) and the long-term group (more than 48 months) group. Occupying ratio, type of OPLL, shape of ossified lesion, cervical sagittal alignment, grade of signal intensity on MRI, and Japanese Orthopedic Association (JOA) score were examined. Surgical outcomes of ACCF went into reverse at 48-month follow-up period. In the short-term group, JOA recovery rate had no difference between ACCF and LP. In the long-term group, the ACCF recovery rate (78.5 ± 31.0) was significantly higher than the LP recovery rate (48.4 ± 54.9) (P = 0.008). In the short-term group, old age (p = 0.011), hill shape (p = 0.013), and high grade of MRI signal intensity (p = 0.040) had negative effects on recovery rate. On the other hand, in the long-term group, LP (p = 0.021) and a high grade of MR signal intensity (p = 0.017) independently and negatively affected recovery rate. Long-term surgical outcomes of ACCF became better than those of LP at more than 48-month follow-up period. High-grade MRI signal changes and the LP surgical procedure were independent negative factors for long-term surgical outcomes in patients with OPLL. Direct decompression of the spinal cord with ACCF provides better long-term stable neurologic outcomes than LP.

Influence of plate fixation on cervical height and alignment after one- or two-level anterior cervical discectomy and fusion.

PURPOSE: To evaluate the efficacy of plate fixation on cervical alignment after anterior cervical discectomy and fusion (ACDF) using a stand-alone cage (ACDF-CA), compared to ACDF performed using a cage and plate fixation (ACDF-CP) and ACDF using autologous iliac bone graft and plate fixation (ACDF-AP), for the treatment of one- or two-level cervical degenerative disease. A second objective was to assess the clinical and radiological outcomes between the groups. METHODS: A total of 247 patients underwent ACDF and were divided into three groups: those who underwent ACDF-CA (n = 76), ACDF-CP (n = 82) or ACDF-AP (n = 89). Fusion rate and time-to-fusion, global cervical and segmental angle, fused segment height, subsidence rate, and clinical outcomes, were measured using the visual analogue scale (VAS), Oswestry Neck Disability Index (NDI), and Robinson's criteria, assessed preoperatively, immediately postoperatively, and at least 24 months, postoperatively. RESULTS: ACDF-AP was associated with the shortest mean time-to-fusion, followed by ACDF-CP and ACDF-CA. Compared to the preoperative status, the fused segment height and segmental angle increased in all groups immediately postoperatively, being well-maintained in patients who underwent ACDF-AP, while decreasing in those who underwent ACDF-CP and ACDF-CA procedures. Global cervical lordosis increased with ACDF-AP, but decreased immediately postoperatively with ACDF-CP and ACDF-CA, and at the final follow-up. Univariate analysis confirmed that a change in fused segment height was positively associated with a change in both segmental and global cervical angles. Clinical outcomes, namely VAS and NDI scores, as well as Robinson's criteria, were comparable among the three techniques. CONCLUSIONS: Supplementation with plate fixation, especially using autologous iliac bone graft, is beneficial for maintaining the fused segment height and cervical spine curvature, as well as reducing time-to-fusion and subsidence rate.

An effect comparison of teriparatide and bisphosphonate on posterior lumbar interbody fusion in patients with osteoporosis: a prospective cohort study and preliminary data.

PURPOSE: Our purpose was to evaluate the efficacy of teriparatide for posterior lumbar interbody fusion (PLIF) in osteoporotic women. METHODS: Forty-seven osteoporotic patients underwent PLIF with pedicle screw fixation for degenerative lumbar stenosis and instability. Patients were divided into two groups. The teriparatide group (n = 23) was injected subcutaneously with teriparatide (20 µg daily) for 3-month cycles alternating with 3-month periods of oral sodium alendronate for 12 months. The bisphosphonate group (n = 24) was administered oral sodium alendronate (91.37 mg/week) for ≥1 year. Serial plain radiography, computed tomography, and bone mineral densitometry (BMD) evaluations were performed. Fusion rate, bony fusion duration, and T score changes were evaluated. Clinical data [pain scores, Prolo's functional scale, and Oswestry disability index (ODI)] were also serially evaluated. RESULTS: The teriparatide group showed earlier fusion than the bisphosphonate group. The average period of bone fusion was 6.0 ± 4.8 months in the teriparatide group but 10.4 ± 7.2 months in the bisphosphonate group. The bone fusion rate in the teriparatide group was higher than that in the bisphosphonate group at 6 months; however, there was no difference 12 and 24 months after surgery. Pain scores and ODI were not significantly different between groups. BMD scores in the teriparatide group were significantly improved compared with the bisphosphonate group 2 years after surgery. CONCLUSIONS: There was no significant improvement in overall fusion rate and clinical outcome in our patients after injection of teriparatide, but the teriparatide group showed faster bony union and highly improved BMD scores.

Effectiveness and tolerability of transdermal buprenorphine patches: a multicenter, prospective, open-label study in Asian patients with moderate to severe chronic musculoskeletal pain.

BACKGROUND: We examined the effectiveness and tolerability of transdermal buprenorphine (TDB) treatment in real-world setting in Asian patients with musculoskeletal pain. METHODS: This was an open-label study conducted in Hong Kong, Korea, and the Philippines between June 2013 and April 2015. Eligible patients fulfilled the following criteria: 18 to 80 years of age; clinical diagnosis of osteoarthritis, rheumatoid arthritis, low back pain, or joint/muscle pain; chronic non-malignant pain of moderate to severe intensity (Box-Scale-11 [BS-11] pain score ≥ 4), not adequately controlled with non-opioid analgesics and requiring an opioid for adequate analgesia; and no prior history of opioid treatment. Patients started with a 5 µg/h buprenorphine patch and were titrated as necessary to a maximum of 40 µg/h over a 6-week period to achieve optimal pain control. Patients continued treatment with the titrated dose for 11 weeks. The primary efficacy endpoint was the change in BS-11 pain scores. Other endpoints included patients' sleep quality and quality of life as assessed by the 8-item Global Sleep Quality Assessment Scale (GSQA) questionnaire and the EuroQol Group 5-Dimension Self-Report Questionnaire-3 Level version (EQ-5D-3 L), respectively. Tolerability was assessed by collecting adverse events. RESULTS: A total of 114 eligible patients were included in the analysis. The mean BS-11 score at baseline was 6.2 (SD 1.6). Following initiation of TDB, there was a statistically significant improvement in BS-11 score from baseline to visit 3 (least squares [LS] mean change: -2.27 [95% CI -2.66 to -1.87]), which was maintained till the end of the study (visit 7) (LS mean change: -2.64 [95% -3.05 to -2.23]) (p < 0.0001 for both). The proportion of patients who rated sleep quality as 'good' increased from 14.0% at baseline to 26.9% at visit 6. By visit 6, the mean EQ VAS score increased by 7.7 units (SD 17.9). There were also significant improvements in patients' levels of functioning for all EQ-5D-3 L dimensions from baseline at visit 6 (p < 0.05 for all). Seventy-eight percent of patients reported TEAEs and 22.8% of patients discontinued due to TEAEs. TEAEs were generally mild to moderate in intensity (96.5%). CONCLUSIONS: TDB provides effective pain relief with an acceptable tolerability profile over the 11-week treatment period in Asian patients with chronic musculoskeletal pain. More studies are needed to examine the long-term efficacy and safety of TBD treatment in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT01961271 . Registered 7 October 2013 (retrospectively registered; first patient was enrolled on 28 June 2013 and last patient last visit date was 26 Apr 2015).

A morphometric analysis of contralateral neural foramen in TLIF.

STUDY DESIGN: A retrospective review PURPOSE: This study was designed to compare postoperative changes in neural foramen between transforaminal lumbar interbody fusion (TLIF) and posterior lumbar interbody fusion (PLIF). METHODS: A retrospective analysis of 67 patients was compared to the change of neural foraminal morphometry of the two techniques. 33 patients (40 levels) had TLIF and 34 patients (39 levels) had PLIF. The two groups had similar demographic profiles. Radiological parameters including anterior and posterior disc height, foraminal height (FH), and segmental Cobb angle (SCA) were measured by sagittally reconstructed computed tomography images before and after surgery. Cage position was designated as contralateral, middle, and ipsilateral in the TLIF group. Surgical results were assessed by Odom criteria, visual analog scale (VAS), and Oswestry disability index (ODI) scores. RESULTS: The TLIF and PLIF group showed no bilateral difference in FH. The TLIF group had increased contralateral SCA compared to the ipsilateral side postoperatively. FH differed according to cage position in the TLIF group. When a cage was inserted deeply into the contralateral side, contralateral FH increased significantly. However, when a cage was inserted into the ipsilateral side, contralateral FH decreased significantly. Back pain was significantly lower in the TLIF group at 1 and 6 months than in the PLIF group. However, ODI and Odom scale scores were not different between the groups. CONCLUSIONS: TLIF may induce uneven changes in foraminal morphometry. Cage position may be the major determinant of this result.

Stand-alone Cervical Cages Versus Anterior Cervical Plates in 2-Level Cervical Anterior Interbody Fusion Patients: Analysis of Adjacent Segment Degeneration.

STUDY DESIGN: A retrospective study. OBJECTIVE: To analyze adjacent segment degeneration (ASD) in 2-level anterior cervical discectomy, comparing fusion with stand-alone cages [anterior cervical discectomy and fusion (ACDF)-CA] and fusion with cage and plate constructs (ACDF-CPC) with respect to clinical outcomes and radiologic changes. SUMMARY OF BACKGROUND DATA: ACDF using a stand-alone cage or a cage and plate construct is a popular procedure. However, there is lack of knowledge concerning ASD between the 2 procedures. METHODS: A total of 42 consecutive patients who underwent 2-level ACDF-CA or ACDF-CPC for 2-level cervical disk disease and who completed 2 years of follow-up were included in this study. The patients were divided into 2 groups: ACDF-CA group (n=22) and ACDF-CPC group (n=20). The following parameters were assessed using radiographs: disk space narrowing, anterior osteophyte formation, calcification of the anterior longitudinal ligament, and fusion status. Clinical outcomes were assessed using the Robinson criteria. RESULTS: No difference in clinical outcomes was observed between the 2 groups. Moreover, the ACDF-CPC group showed a similar fusion rate compared with the ACDF-CA group (100% vs. 95%, P=0.335). There was also no statistical significance in anterior osteophyte formation and calcification of the anterior longitudinal ligament. However, mean intervertebral disk height change of an adjacent segment was significantly lower in the ACDF-CA group than the ACDF-CPC group (upper level: 0.08±0.24 vs. 0.49±0.35; lower level: 0.06±0.41 vs. 0.49±0.28; P<0.01). CONCLUSIONS: The use of a cage with or without plate constructs in 2-level ACDF provides similar clinical results and fusion rates. Notwithstanding, ACDF-CPC showed a higher incidence of ASD than ACDF-CA over the 2-year follow-up.

Long-term surgical outcomes of cervical myelopathy with athetoid cerebral palsy.

PURPOSE: To understand the long-term surgical outcomes and prognostic factors for the operative treatment of cervical myelopathy (CM) in patients with athetoid cerebral palsy (ACP). METHODS: We retrospectively reviewed 24 patients with ACP who underwent surgery for CM at our hospital between March 2002 and June 2008. All patients had more than 5 years follow-up. Anterior fusion (11 patients), posterior fusion (1 patient), or combined anterior and posterior (AP) fusion (7 patients) and C1-2 fusion (5 patients) surgeries were performed. Surgical outcomes (average follow-up 102 months), as assessed using modified JOA (mJOA) scores, the Neck Disability Index (NDI), and a visual analog scale (VAS) were compared between the preoperative and postoperative states. RESULTS: Preoperatvie cervical kyphosis decreased mJOA scores significantly. Long-term follow-up clinical outcomes demonstrated that 10 patients showed favorable (excellent and good) outcomes and 11 patients had non-favorable (fair and worse) outcomes. According to the mJOA scores, patients showed postoperative improvement (7.10-10.45). NDI decreased from 68.46 to 31.66. A second operation was done in seven cases due to instrument failure, progressive kyphotic deformities and adjacent segment degeneration. A preoperative botulinum toxin injection significantly decreased (p < 0.05) the incidence of a second operation. CONCLUSIONS: Patients with ACP have high incidence of instrument failure. Strong surgical fixation, bone fusion and perioperative immobilizations using botulinum toxin injection should be carefully planned preoperatively.

Co-transplantation of bone marrow-derived mesenchymal stem cells and nanospheres containing FGF-2 improve cell survival and neurological function in the injured rat spinal cord.

BACKGROUND: Spinal cord injury (SCI) is a devastating and irreversible event, and much research using fibroblast growth factor-2 (FGF-2) has been performed to test its capacity to blunt the effects of SCI as well as to provide an environment conducive for SCI repair. METHODS: We tested how the in vitro release of FGF-2 from heparin-conjugated poly(L-lactide-co-glycolide) (PLGA)-conjugated nanospheres (HCPNs) affected the growth of human bone marrow-derived mesenchymal stem cells (hBMSCs), as well as the effects of their co-transplantation in an animal model of SCI. RESULTS: Our results showed that sustained, long-term release of FGF-2 from HCPNs significantly increased hBMSCs proliferation in vitro, and that their co-transplantation following rat SCI lead to increased functional improvement, a greater amount of hBMSCs surviving transplantation, and a greater density of neurofilament-positive cells in the injury epicenter. CONCLUSION: These results suggest a proliferative, protective, and neural inductive potential of FGF-2 for transplanted hBMSCs, as well as a possible role for sustained FGF-2 delivery along with hBMSCs transplantation in the injured spinal cord. Future studies will be required to ascertain the safety FGF-2-containing HCPNs before clinical application.

Robotic resection of huge presacral tumors: case series and comparison with an open resection.

STUDY DESIGN: Clinical case series and analysis. OBJECTIVE: The purpose of the present study is to evaluate the advantages and disadvantages of robotic presacral tumor resection compared with conventional open approach. SUMMARY OF BACKGROUND DATA: Conventional open approach for huge presacral tumors in the retroperitoneal space often demands excessive hospitalization and poor cosmesis. Furthermore, narrow surgical field sometimes interrupt delicate procedures. METHODS: Nine patients with huge (diameter >10 cm) presacral tumors underwent surgery. Five patients among them had robotic procedure and the others had open transperitoneal tumor resection. Operation time, blood loss, hospitalization, and complications were analyzed. RESULTS: Robotic presacral tumor resection showed shorter operation time, less bleeding, and shorter hospitalization. Moreover, there was no complication related to abdominal adhesion. CONCLUSIONS: Although robotic resection for presacral tumor still has limitations technically and economically, robotic resection for huge presacral tumors demonstrated advantages over open resection specifically for benign neurogenic tumors.

Clinical features and surgical outcomes of primary cauda equina tumours.

BACKGROUND: To identify clinical features, radiological findings and surgical outcomes of primary cauda equina tumours. METHODS: A consecutive series of 64 operations in 60 patients with primary cauda equina tumours from April 1999 to May 2009 at one institution comprised the study. The cases were divided into tumours of neural sheath origin (TNS, n = 48) and tumours of non-neural sheath origin (TNNS, n = 22). We analysed pain intensity, neurological abnormalities, MRI findings, surgical extent and functional outcome. RESULTS: The TNS group showed more leg pain (76 % vs. 44 %, p = 0.019) with higher intensity (6.1 ± 1.5 vs. 4.6 ± 1.9, p = 0.04). Motor weakness and bladder dysfunction were more common in the TNNS group (p = 0.028 and p = 0.00 in each). Flow voids of MRI were more frequently observed in TNNS (50 % vs. 4 %, p = 0.01). The TNS group achieved total removal in all operations compared with total removal in 77 % in the TNNS group (p = 0.001). The TNNS group showed higher recurrence rates (18 % vs. 0 %, p = 0.009). The TNS group showed higher improvement of JOA scores postoperatively (p = 0.049). Surgical complications were observed less frequently in the TNS group (19 % vs. 78 %, p = 0.000). CONCLUSIONS: TNS differs from TNNS by causing more frequent leg pain, higher pain intensity and more frequent flow voids. TNS has better surgical outcomes than TNNS in terms of higher rates of total removal, fewer surgical complications, better functional outcomes and less recurrence.

Comparison of functional and histological outcomes after intralesional, intracisternal, and intravenous transplantation of human bone marrow-derived mesenchymal stromal cells in a rat model of spinal cord injury.

BACKGROUND: Few studies have compared methods of stem cell transplantation. The aim of the present study was to determine the optimal method of delivery of therapeutic stem cells in spinal cord injury (SCI). We compared functional and histologic outcomes after administration of human bone marrow stromal cells (BMSCs) by intralesional (ILT), intracisternal (ICT), and intravenous transplantation (IVT). METHOD: A rat model of spinal cord injury was produced by dropping a 10-g weight, 2 mm in diameter, onto the exposed spinal cords of animals from a height of 25 mm. In each treatment group, 24 animals were randomly assigned for functional assessment and 24 for histologic examination. BMSCs (3 × 10(5), ILT; 1 × 10(6), ICT; 2 × 10(6), IVT) were transplanted 1 week after SCI in numbers determined in previous studies. Basso-Beattie-Bresnahan scoring was performed in all animals weekly for 6 weeks. Spinal cord specimens were obtained from eight animals in each group 2, 4, and 6 weeks after SCI. Viable BMSCs were counted in six sagittal sections from each spinal cord. RESULTS: All three treatment groups showed improved functional recovery compared to controls beginning 2 weeks after stem cell injection (P < 0.01). The ICT group showed the best functional recovery, followed by the ILT and IVT groups, respectively (P < 0.01). Histological analysis showed the largest number of viable BMSCs in the ILT group, followed by the ICT and IVT groups, respectively (P < 0.01). CONCLUSIONS: ICT may be the safest and most effective method for delivering stem cells and improving functional outcome in SCI when no limits are placed on the number of cells transplanted. As research on enhancing engraftment rates advances, further improvement of functional outcome can be expected.

Stand-alone cervical cages versus anterior cervical plate in 2-level cervical anterior interbody fusion patients: clinical outcomes and radiologic changes.

STUDY DESIGN: Retrospective study. OBJECTIVES: To compare the efficacy of 2-level anterior cervical discectomy and fusion with cage alone (ACDF-CA) and with cage and plate construct (ACDF-CPC) with regard to clinical outcome and radiologic changes. SUMMARY OF BACKGROUND DATA: The use of stand-alone cervical interbody cages in ACDF has become popular, but high subsidence rates have been reported in the literature. METHODS: A total of 54 consecutive patients who underwent 2-level ACDF-CA or ACDF-CPC after suffering from cervical radiculopathy were divided into 2 groups: group A (n = 28) underwent ACDF-CA, group B (n = 26) underwent ACDF-CPC. Fusion rate, global and segmental kyphosis, disk height, and subsidence rate were assessed by radiolographs. Clinical outcomes were assessed using Robinson's criteria. RESULTS: Solid fusion was achieved in 96.43% (27/28) in group A and in 96.15% (25/26) in group B. Fusion segmental kyphosis of >5 degrees occurred in 14.29% (4/28) of group A and in 7.69% (2/26) of group B; however, there was no statistical difference between the 2 groups (P>0.05). Subsidence occurred in 35.71% (10/28) of group A as compared with 11.54% (3/26) of group B (P<0.05). Clinical outcomes were similar in the 2 treatment groups. CONCLUSIONS: The use of cage and plate construct in 2-level ACDF results in a shorter fusion duration and a lower subsidence rate than that of cage alone; however, there is no significant difference in the postoperative global and segmental alignment and clinical outcomes between groups.

A histopathological diagnostic marker for human spinal astrocytoma: expression of glial fibrillary acidic protein-δ.

Although histopathological diagnosis of spinal cord astrocytomas is important for postoperative treatment planning and prognosis, there is a lack of reliable immunohistochemical markers. The purpose of our study was to assess the expression pattern of GFAP-δ in spinal cord astrocytomas in human patients and to evaluate the utility of GFAP-δ as an immunohistochemical diagnostic marker. A total of 22 patients with spinal cord astrocytic tumors were included in this study. Patients were classified according to the WHO designation of human astrocytic tumors; three patients had grade 1 astrocytomas, 14 had grade 2, and five had Grade 3. Normal control spinal cord tissues were obtained at autopsy from the cervical spinal cords of ten patients with no history of cervical trauma or neurological disease. We evaluated BRAF, IDH1, GFAP, and GFAP-δ immunoreactivity in control tissues and astrocytomas. In normal control tissues, GFAP immunoreactivity was detected in astrocytes whereas GFAP-δ immunoreactivity was observed in very few astrocytes adjacent to the subpial layer of the spinal cord. GFAP-δ immunoreactivity was significantly correlated with spinal cord astrocytoma grade in astrocytomas compared to that in normal control tissues. The optical density of GFAP-δ increased significantly with astrocytoma grade (correlation coefficient, R (2) = 0.680). Also, BRAF and IDH1 immunoreactivity were detected in astrocytoma. We suggest that GFAP-δ may be an additional, reliable histopathological diagnostic marker for spinal cord astrocytomas.

The clinical features and surgical outcomes of pediatric patients with primary spinal cord tumor.

BACKGROUND: Primary spinal cord tumors (PSCTs) in pediatric patients are rare, with a reported overall incidence rate of 1-2.6 per one million children. We reviewed our experience of surgically treated 27 pediatric patients with PSCT and discussed the clinical features, radiological findings, surgical outcomes, and prognostic factors. METHODS: Between March 1999 and March 2010, a total of 27 pediatric patients with PSCT were surgically treated in a single institution. We retrospectively analyzed their data. RESULTS: There were 13 females and 14 males, and their ages ranged from 6 months to 19 years (mean age, 12.1 years). The most common presenting symptom was motor weakness, and the histologic type of the tumors were mainly schwannoma, astrocytoma, and ependymoma. The tumor was completely resected in 17 patients, subtotally resected in 7 patients, and partial resection or biopsy was performed in 3 patients. Adjuvant chemotherapy was performed in 9 patients, and radiotherapy in 12 patients, respectively. The average follow-up period was 33.5 months (1.17-129). Five patients experienced the progression of disease, and three of them expired. The mean time for disease progression was 19.0 months (4.5-48.7). CONCLUSIONS: PSCT in pediatric patients can be surgically removed with an acceptable low surgical morbidity. Progression-free survival was found to be related to the grade of tumor and the extent of tumor resection. Early diagnosis and treatment anticipate good functional neurologic outcome.

Thoracolumbar extradural arachnoid cysts: a study of 14 consecutive cases.

BACKGROUND: To investigate characteristic clinical and radiological features of extradural arachnoid cysts (EDACs) in the thoracolumbar region, a retrospective review of medical records and imaging studies was performed. EDACs are well known but relatively rare lesions in the thoracolumbar spinal canal. The most common site is the lower thoracic spine, and it may cause neurological symptoms by compressing the spinal cord or nerve root. In this study, the pathogenesis, symptomatology, diagnostic approach, and surgical management of EDACs will be discussed. METHODS: We studied 14 consecutive patients who were surgically treated for EDACs in the thoracolumbar region at our institute between March 2000 and January 2011. The history, clinical presentations, image findings, operative findings, and surgical outcomes of these patients were retrospectively analyzed. The mean follow-up period was 28 months (range: 6-72 months). RESULTS: Progressive motor weakness was the predominant symptom in all patients. Nine patients had radicular leg pain and back pain in the thoracolumbar area. On MRI, the cyst compressed the dural sac and spinal cord posteriorly typically with bilateral foraminal extensions. On radiological study, a communication point with the subarachnoid was hardly observed. The surgical treatment of EDACs included complete resection of the walls and closing the communicating point with the subarachnoid space. All patients showed excellent outcomes according to Odom's criteria without recurrence. One CSF leakage and one postoperative hematoma were noted. CONCLUSIONS: Thoracolumbar EDAC patients presented paraparesis and leg pain. Complete excision and closing the communicating point with the subarachnoid space were the choices of treatment, and the outcomes were favorable.

Radiological Changes in Adjacent and Index Levels after Cervical Disc Arthroplasty.

PURPOSE: The purpose of this retrospective study was to evaluate radiological and clinical outcomes in patients undergoing cervical disc arthroplasty (CDA) for cervical degenerative disc disease. The results may assist in surgical decision-making and enable more effective and safer implementation of cervical arthroplasty. MATERIALS AND METHODS: A total of 125 patients who were treated with CDA between 2006 and 2019 were assessed. Radiological measurements and clinical outcomes included the visual analogue scale (VAS), the Neck Disability Index (NDI), and the Japanese Orthopaedic Association (JOA) myelopathy score assessment preoperatively and at ≥2 years of follow-up. RESULTS: The mean follow-up period was 38 months (range, 25-114 months). Radiographic data demonstrated mobility at both the index and adjacent levels, with no signs of hypermobility at an adjacent level. There was a non-significant loss of cervical global motion and range of motion (ROM) of the functional spinal unit at the operated level, as well as the upper and lower adjacent disc levels, compared to preoperative status. The cervical global and segmental angle significantly increased. Postoperative neck VAS, NDI, and JOA scores showed meaningful improvements after one- and two-level CDA. We experienced a 29.60% incidence of heterotrophic ossification and a 3.20% reoperation rate due to cervical instability, implant subsidence, or osteolysis. CONCLUSION: CDA is an effective surgical technique for optimizing clinical outcomes and radiological results. In particular, the preservation of cervical ROM with an artificial prosthesis at adjacent and index levels and improvement in cervical global alignment could reduce revision rates due to adjacent segment degeneration.

Novel C-arm-based planning robotic spinal surgery in a cadaver model using quantitative accuracy assessment methodology.

BACKGROUND: This preclinical study emulating the clinical environment quantitatively analysed the accuracy of pedicle screw insertion using a navigated robotic system. METHODS: Pedicle screws were placed from T7 to L5 in the whole-body form of a cadaver. After the insertion of multiple artificial markers into each vertebra, errors between the planned insertion path and the inserted screw were quantified using the Gertzbein-Robbins system (GRS) and offset calculation. RESULTS: A total of 22 screws were placed. Almost all (95.45% [21/22]) were classified as GRS A or B, while one (4.55%) was GRS C. The mean and standard deviations of entry, tip, and angular offset were 1.78 ± 0.94 mm, 2.30 ± 1.01 mm, and 2.64 ± 1.05°, respectively. CONCLUSIONS: This study demonstrated that pedicle screw insertion using a navigated robotic system had high accuracy and safety. A future clinical study is necessary to validate our findings.

Association of frailty with regional sagittal spinal alignment in the elderly.

The degenerative changes in the spine of the frail elderly gradually exacerbate the alignment of the spine as the degeneration progresses. This study was conducted to assess the relationship between frailty and spine sagittal alignment measured in terms of global, cervical, thoracic, and lumbo-pelvic parameters. In total, 101 patients aged 75 years and older hospitalized for spine surgery were prospectively enrolled. We evaluated spinal sagittal parameters by dividing them into global (C7 sagittal vertical axis [SVA] and T1 pelvic angle [T1PA]), cervical (the C2-7 Cobb angle, Jackson line, and C2-7 plumb line), thoracic (thoracic kyphosis [TK]), and lumbo-pelvic (pelvic tilt [PT] and pelvic incidence minus lumbar lordosis value [PI-LL]). Patient characteristics; the Fatigue, Resistance, Ambulation, Illness, Loss of Weight (FRAIL) scale; and sagittal spinal parameters were included in the analysis. Multiple regression analysis was performed to identify associations between the FRAIL scale and sagittal spinal parameters. The FRAIL scale showed correlations with global sagittal parameters (C7 SVA [ß = 0.225, p = 0.029] and T1PA [ß = 0.273, p = 0.008]) and lumbo-pelvic parameters (PT [ß = 0.294, p = 0.004] and PI-LL [ß = 0.323, p = 0.001). Cervical and thoracic parameters were not directly associated with the FRAIL scale. LL and PI-LL were associated with TK, and TK was associated with cervical parameters (the C2-7 Cobb angle, Jackson line and C2-7 plumb line). In conclusion, frailty status could be an important factor that influences sagittal spinal alignment in the elderly. In this study, it was found that frailty mainly affected the balance of lumbo-pelvic alignment, and consequently affected the balance of the whole spine.

The clinical features and surgical outcomes of patients with intramedullary spinal cord cavernous malformations.

BACKGROUND: Cavernous malformations (CMs) are not uncommon, but most of them are found to be located intracranially. Intramedullary CMs are rare, accounting for only 3-5% of identified total central nervous system lesions. The natural history of intramedullary CMs and their clinical features, including the risk of hemorrhage from a large series, still remains unclear and needs to be elucidated. We review our experience with surgically treated patients with intramedullary CMs and discuss the clinical features and surgical outcomes. METHODS: Between March 2004 and March 2010, a total of 21 patients with intramedullary spinal cord CMs were surgically treated in a single institution. Data from 21 patients were retrospectively analyzed. RESULTS: There were 13 females and 8 males ranging in age from 10 to 70 years (mean age 39.3 years). All patients harbored single symptomatic CM of the nervous system, and multiple lesions were not found. The annual retrospective hemorrhage rate was 2.18% per patient/year. All but one CM were completely resected, and the average follow-up period was 22.1 months (1-73 months). Ten of the 21 patients experienced an improvement in neurological state, 9 patients remained unchanged, and 2 patients experienced worsening of their conditions. CONCLUSIONS: Symptomatic intramedullary CMs should be surgically removed to avoid further neurological deterioration. Though there are some limitations due to the retrospective nature of this study and its small number of patients, the prognosis was found to be related to the preoperative neurological state and to the type of symptom presentation.