Japanese Orthopaedic Association Recovery Rate Research Articles

Comparison of laminoplasty and posterior fusion surgery for cervical ossification of posterior longitudinal ligament

This prospective multicenter study, established by the Japanese Ministry of Health, Labour and Welfare and involving 27 institutions, aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL), in order to address the controversy surrounding the role of instrumented fusion in cases of posterior surgical decompression for OPLL. 478 patients were considered for participation in the study; from among them, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, there were no significant differences among the participants in terms of patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments. The overall risk of perioperative complications was found to be lower with LM (odds ratio [OR] 0.40, p = 0.006), and the rate of C5 palsy occurrence was significantly lower with LM (OR 0.11, p = 0.0002) than with PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients who had PF was significantly smaller than in those who had LM. However, multivariable logistic regression analysis showed no significant difference among the participants in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in the LM group than in the PF group (OR 2.73, p = 0.0002). Both LM and PF for cervical myelopathy due to OPLL had resulted in comparable postoperative outcomes at 2 years after surgery.

Double Dome Laminoplasty: A Novel Technique for C2 Decompression.

ObjectiveTo introduce a new surgical technique - double dome laminoplasty for decompression of the entire C2 lamina and preservation of an extensor muscle insertion. MethodsEleven consecutive cervical myelopathy patients due to ossification of the posterior longitudinal ligament involving the Axis (C2) area were contained at this study. Direct decompression was evaluated as an increasing rate in space available cord (%) and posterior cord shift (mm) at C2 level. The Japanese Orthopaedic Association (JOA) score, visual analogue scale, and C2–7 Cobb angle in a neutral lateral x-ray were analyzed. ResultsThe mean increase in space available for spinal cord at the C2 level, average posterior cord shift, and JOA recovery rate were 69.7%, 5.3±0.15 mm, and 58.0%, respectively. Cervical lordotic angle was maintained in all patients. One patient reported neck pain (visual analogue scale 6) postoperatively. No specific complications such as C2 laminar fracture or insufficient decompression were observed. ConclusionWe recommend double dome laminoplasty for treating patients with cervical myelopathy involving the C2 area to avoid C2 laminectomy, reduce postoperative neck pain, and maintain lordotic cervical spine alignment.

Microendoscopic Decompression for Lumbar Spinal Stenosis Associated with Adjacent Segment Disease following Lumbar Fusion Surgery: 5-year Follow-up of a Retrospective Case Series.

Surgical treatment options for lumbar spinal stenosis (LSS) based on adjacent segment disease (ASD) after spinal fusion typically involve decompression, with or without fusion, of the adjacent segment. The clinical benefits of microendoscopic decompression for LSS based on ASD have not yet been fully elucidated. We aimed to investigate the clinical results of microendoscopic spinal decompression surgery for LSS based on ASD. From 2011 to 2014, consecutive patients who underwent microendoscopic spinal decompression without fusion for LSS based on ASD were enrolled. Data of 32 patients (17 men and 15 women, with a mean age of 70.5 years) were reviewed. Japanese Orthopaedic Association score and low back pain/leg pain visual analog scale score were utilized to measure neurologic and axial pain outcomes, respectively. Additionally, after the surgeries, we analyzed the magnetic resonance imaging (MRI), computed tomography (CT) scans, or radiographs to identify any new instabilities of the decompressed segments or progression of ASD adjacent to the decompressed segments. The Japanese Orthopaedic Association recovery rate at the 5-year postoperative visit was 49.2%. The visual analog scale scores for low back pain and leg pain were significantly improved. The minimum clinically important difference for leg pain (decrease by ≥24 mm) and clinically important difference for low back pain (decrease by ≥38 mm) were achieved in 84% (27/32) and 72% (23/32) of cases, respectively. Regarding new instability after microendoscopic decompression, no cases had apparent spinal instability at the decompression segment and adjacent segment to the decompressed segment. Microendoscopic spinal decompression is an effective treatment alternative for patients with LSS caused by ASD. The ability to perform neural decompression while maintaining key stabilizing structures minimizes subsequent clinical instability. The substantial clinical and economic benefits of this approach may make it a favorable alternative to performing concurrent fusion in many patients.

Surgical Outcomes of Selective Laminectomy for Patients With Cervical Kyphosis: A Retrospective Study of 379 Cases.

A retrospective study. This study aimed to investigate the impact of cervical kyphosis on patients with cervical spondylotic myelopathy (CSM) following selective laminectomy (SL) regarding posterior spinal cord shift (PSS), and a number of SLs. We evaluated 379 patients with CSM after SL. The patients with kyphosis (group K) were compared with those without kyphosis (group L). Moreover, groups K and L were divided into subgroups KS and KL (SLs ≤ 2) and LS and LL (SLs ≥ 3), respectively, and analyzed. Receiver operating characteristic (ROC) curve analysis was performed to determine the cut-off value of the C2-C7 angle for satisfactory surgical outcomes, which was defined as a Japanese Orthopaedic Association (JOA) recovery rate of ≥50% in group KS. The average PSS (mm) in group K was smaller than that in group L (.8 vs 1.4; P < .01), but the JOA recovery rate was comparable between the 2 groups. Meanwhile, the mean PSS and JOA recovery rate (%) in group KS was lower than those in group KL, respectively (.3 vs 1.0; P < .01, 35.1 vs 52.3; P = .047). Moreover, the average PSS of group KS (.6) was smaller than those of other subgroups ( < .01). In addition, the ROC curve analysis showed that the C2-C7 angle of -14.5° could predict satisfactory surgical outcomes in group KS. Selective laminectomy is not contraindicated for patients with kyphosis, but a larger number of SLs may be indicated for the patients with C2-C7 angles of ≤ -14.5°.

Comparison of Surgical Outcomes Between Staged and Simultaneous Decompression of Discontinuous Thoracic Ossification of the Ligamentum Flavum: A Retrospective Study

Discontinuous thoracic ossification of the ligamentum flavum (TOLF) is diagnosed according to the number and distribution of involved segments seen on magnetic resonance images. When TOLF causes thoracic myelopathy, surgical intervention for these lesions becomes unavoidable. However, there are few reports on the outcomes of surgery for discontinuous TOLF. The study included 26 patients of mean age 55.0 years who underwent simultaneous (n= 16) or staged (n= 10) decompression of discontinuous TOLF between July 2006 and June 2016. Final neurologic status was evaluated using the modified Japanese Orthopaedic Association (JOA) score. The surgical data and incidence ofcomplications were compared. The mean follow-up duration was 73.3 months. There was no between-group difference in number of levels decompressed or the amount of intraoperative blood loss. There was a significant improvement in the JOA score from 4.0 before surgery to 8.0 postoperatively, with an average recovery rate of 58.3%. The JOA recovery rate was significantly better in the staged group than simultaneous group (68.4% vs. 52.0%, P < 0.05). However, the incidence of complications was similar between the staged and simultaneous groups including for dural tear (1 vs. 6, P= 0.19), cerebrospinal fluid leak (4 vs. 6, P= 1.00), and transient neurologic deterioration (0 vs. 2, P= 0.51). The surgical outcome of staged decompression for discontinuous TOLF seems to be better than that of simultaneous decompression. The complication rates of these 2 strategies are similar.

Long-term Clinical Outcomes of Microendoscopic Laminotomy for Cervical Spondylotic Myelopathy: A 5-Year Follow-up Study Compared With Conventional Laminoplasty.

This was a retrospective cohort study. The objective of this study was to characterize the long-term clinical and radiographic results of articular segmental decompression surgery using endoscopy [cervical microendoscopic laminotomy (CMEL)] for cervical spondylotic myelopathy (CSM) and to compare outcomes to conventional expansive laminoplasty (ELAP). The spinal cord compression in CSM consists of a pincer mechanism due to bulging disk and a hypertrophied ligamentum flavum. The long-term clinical benefits of segmental decompression surgery, which removes the dorsal compressive elements of articular segment in CSM patients, have not yet been elucidated. Consecutive patients with CSM who required surgical treatment were enrolled. All enrolled patients (n=81) underwent CMEL or ELAP. All patients were followed postoperatively for >5 years. The preoperative and 5-year follow-up evaluation included neurological assessment [Japanese Orthopaedic Association (JOA) score], JOA recovery rates, axial neck pain (visual analog scale), and cervical sagittal alignment (C2-C7 subaxial cervical angle). Sixty-four patients (CMEL group: 33, ELAP group: 31) were included for analysis. The preoperative JOA score was 10.1 points in the CMEL group and 11.1 points in the ELAP group (P=0.15). The JOA recovery rates were similar, 58.6% in the CMEL group and 55.2% in the ELAP group (P=0.55). The axial neck pain in the CMEL group was significantly lower than that in the ELAP group (P<0.01). At 5-year follow-up, cervical alignment was more favorable in the CMEL group, with an average 2.9 degrees gain in lordosis [vs. 2.3 degrees loss of lordosis in the ELAP group (P<0.05)] and lower incidence of postoperative kyphosis. CMEL is a novel, less invasive, technique that allows for multilevel posterior cervical decompression for treatment of CSM. Our 5-year follow-up data demonstrates that patients after CMEL have similar neurological outcomes to conventional laminoplasty, with significantly less postoperative axial pain and improved subaxial cervical lordosis when compared with their traditional laminoplasty counterparts.

One-stage posterior laminectomy with instrumented fusion and foraminotomy for cervical ossification of posterior longitudinal ligament with radiculopathy pain

ObjectiveTo explore the clinical efficacy of posterior LFF for cervical OPLL with radicular pain of upper limbsMethodsBetween January 2014 and January 2018, 48 OPLL patients with radicular pain symptoms of upper limbs who underwent a one-stage posterior laminectomy and instrumented fusion with/without foraminotomy were reviewed retrospectively and divided into two groups: LF group (laminectomy with instrumented fusion without foraminotomy) and LFF group (laminectomy with instrumented fusion and foraminotomy). Clinical data were assessed and compared between the two groups. The radicular pain of upper limbs and neck was measured using the visual analog scale (VAS). The neurological function was evaluated with the American Spinal Injury Association (ASIA) scale. Changes of sagittal alignment were investigated by postoperative plain x-ray or computed tomography (CT). Moreover, the decompression of the spinal cord was evaluated based on postoperative MRI.ResultsAll the 48 patients were followed up for 24–42 months with an average follow-up time of 31.1±5.3 months. A total of 56 cervical intervertebral foramens were enlarged in 48 patients, including 40 cases (83.3%) with 1 intervertebral foramen enlargement and 8 cases (16.7%) with 2 intervertebral foramen enlargements. There were no significant differences in intraoperative blood loss, postoperative drainage amount, Japanese Orthopaedic Association (JOA) scores, JOA recovery rates, VAS scores for neck pain, and ASIA grade between two groups. The mean operative time was shorter in the LF group compared with the LFF group. The VAS score for arm pain was significantly lower while the surgical duration was longer in group B. No statistical difference was observed between the two groups in terms of C2–C7 SVA, cervical lordosis, focal angulation at the foraminotomy segment, and local spinal cord angle. Compared with the LF group, there was no segmental kyphosis or instability where the additional posterior foraminotomy was performed in the LFF group.ConclusionsOne-stage posterior LFF can achieve satisfied clinical efficacy in improving neurological function and relieving the radicular pain of the upper limbs for OPLL patients with radiculopathy symptoms.

The Kappa Line as a Regional Modification of the K-line: A Predictor of Neurological Outcome and Indicator of the Adequate Level of Decompression in Selective Laminoplasty.

This is a retrospective cohort study. The aim was to introduce Kappa line (modification of K-line) for the prediction of postoperative neurological recovery after selective cervical laminoplasty (LMP) and use in determining the decompression level. The K-line is a radiographic marker that can predict prognosis and aid in surgical planning for patients undergoing LMP through C3 to C7. However, its efficacy in LMP involving limited segments is unclear. Furthermore, no specific radiographic marker to predict the prognosis of selective LMP has been reported. Fifty-one consecutive patients with a minimum 2-year follow-up after selective LMP for cervical myelopathy caused by ossification of posterior longitudinal ligament were retrospectively reviewed. The Kappa line was defined as a straight line connecting the midpoints of the spinal canal made by remaining bony structure after decompression procedures on a plain lateral radiograph in the neutral position. Patients were classified as K-line (+) or (-) and Kappa line (+) or (-) based on whether the ossified mass crossed the indicator line. The Kappa line (+) group demonstrated significantly higher Japanese Orthopaedic Association (JOA) recovery rate (P=0.01), final JOA score (P<0.01), and dural sac diameter (P<0.01) postoperatively than the Kappa line (-) group. Cord compression grade was significantly lesser in the Kappa line (+) group. However, the K-line-based classification did not demonstrate significant difference in JOA recovery rate, final JOA score, and cord compression grade between the (+) and (-) groups; the dural sac diameter was significantly higher in the K-line (+) group (P<0.01). The Kappa line showed better correlation with ossification of posterior longitudinal ligament size and cervical alignment, providing better prediction of neurological recovery and remaining cord compression following selective LMP. Therefore, the Kappa line can aid in determining the level of decompression in selective LMP.

Application of open-door laminoplasty with ARCH plate fixation in cervical intraspinal tumors

BackgroundThe open-door laminoplasty is an effective procedure for the treatment of cervical spondylotic myelopathy. However, little information is available about the surgical results of open-door laminoplasty in the treatment of intraspinal tumors. In the present study, we aimed to investigate the clinical effect of open-door laminoplasty with ARCH plate fixation in the treatment of cervical intraspinal tumors.MethodsThis was a retrospective study. From January 2013 to May 2018, 38 patients (13 males and 25 females, the average age of 44 ± 17 years) with cervical intraspinal tumors underwent open-door laminoplasty with ARCH plate fixation in our hospital. The operation time, blood loss, pre- and postoperative visual analog scale (VAS), and Japanese Orthopedic Association (JOA) scores were determined. To determine the radiographic outcomes, cervical X-ray film and magnetic resonance imaging (MRI) were performed before and after the operation, and cervical X-ray sagittal film was used to measure Cobb angle. The clinical data before and after the operation were compared by t-test.ResultsA total of 38 patients underwent a successful operation and demonstrated primary healing. The average operation time was 113 ± 12 min. The average blood loss was 120 ± 19 mL. All patients were followed up for 26.1 ± 2.8 months, and the final follow-up time was more than 24 months. VAS scores were much better at 24 months after operation compared with those before the operation, which were decreased from 6.1 ± 1.1 to 1.4 ± 0.7 (t = 32.63, P < 0.01). The JOA score was improved from 9.9 ± 1.5 to 15.5 ± 0.6 (t = − 18.36, P < 0.01), and the mean JOA recovery rate was 79% ± 11% at 24 months after the operation. There was no significant difference in Cobb angle between pre-operation and 24 months after the operation, which was 9.8 ± 2.6 and 10.3 ± 3.1 respectively (t = − 0.61, P > 0.05). Neither spinal malalignment on the coronal plane nor displacement of the laminoplasty flap was observed on postoperative cervical X-ray and MRI examinations at the final follow-up.ConclusionsOpen-door laminoplasty with ARCH plate fixation was a safe and effective surgical approach for the treatment of cervical intraspinal tumors.

Comparison of Surgical Results of the Bridge Crane Technique Versus Laminectomy for the Treatment of Thoracic Myelopathy Caused by Ossification of the Ligamentum Flavum.

A retrospective study. This study aimed to evaluate the safety and effectiveness of the bridge crane technique versus laminectomy for the treatment of thoracic myelopathy caused by ossification of the ligamentum flavum (OLF). Totally 41 patients who underwent surgical decompression due to thoracic OLF from May 2017 to June 2018 in our institution were enrolled in this study and were divided into group BG (bridge crane technique, n = 19) and group L (laminoectomy, n = 22). Demographic data was collected from medical records and the modified Japanese Orthopaedic Association (JOA) scoring system was used to evaluate the neurological outcomes during the follow-up. Surgery-related complications were analyzed. The mean duration of follow-up was comparable between group BG (19.4 ± 1.5 months) and group L (19.6 ± 1.4 months). No statistical differences were observed between two groups in terms of gender, age, duration of symptoms, preoperative occupying rate, involved levels, operation time, intraoperative blood loss, and complications. The JOA score significantly increased at the final follow-up in both groups. However, patients in group BG had higher JOA score and recovery rate (P < 0.05). Four patients in group L experienced complications, including 3 cerebrospinal fluid (CSF) leakage and one postoperative hematoma. Only one patient in group BG had CSF leakage. The results of this study suggested that bridge crane technique may be relatively safe and effective for patients with symptomatic thoracic OLF with more satisfactory clinical improvement. However, high-quality studies are still required to validate the results of this study.

Retrospective comparison of the surgical results for patients with thoracic myelopathy caused by ossification of the posterior longitudinal ligament: Posterior decompression with instrumented spinal fusion versus modified anterior decompression through a posterior approach

BackgroundIn Japan, approximately 75% of patients with thoracic myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) are treated by posterior decompression with instrumented spinal fusion (PDF) because of its efficacy and safety. To achieve more effective decompression of the spinal cord using a posterior approach, anterior decompression through a posterior approach was developed. However, this technique has a high risk of postoperative paralysis. We have added a couple of ingenuities to this procedure (modified Ohtsuka procedure). This study was performed to report the surgical results of our modified Ohtsuka procedure and to compare them with the results of PDF. MethodsThis was a retrospective case series. From 2008 to 2018, we surgically treated 32 patients: 20 patients treated by PDF (PDF group) and 12 patients by our modified Ohtsuka procedure (modified Ohtsuka group) as the initial surgery. All patients were followed up for at least 12 months. The degree of surgical invasion and patients’ neurological condition were assessed. ResultsThe operative duration and intraoperative blood loss indicated no significant differences (PDF vs. Ohtuska: 507 ± 103 vs. 534 ± 99 min, 1022 ± 675 vs. 1160 ± 685 ml, respectively). The preoperative Japanese Orthopaedic Association (JOA) score was 4.5 ± 2.0 in the PDF group and 3.3 ± 1.4 in the modified Ohtsuka group (p < 0.05). However, the latest JOA score and recovery rate were significantly better in the modified Ohtsuka group than in the PDF group (8.9 ± 1.2 vs. 7.4 ± 2.5 and 70.8 ± 17.6% vs. 44.5 ± 40.2%, respectively). Postoperative paralysis did not occur in the modified Ohtsuka group while four patients had it in the PDF group. ConclusionsThe present study clearly indicated the modified Ohtsuka group showed significantly better surgical outcomes than the PDF group with the recovery rate ≥70%.

Exceptional Conditions for Favorable Neurological Recovery After Laminoplasty in Cases with Cervical Myelopathy Caused by K-line (-) Ossification of Posterior Longitudinal Ligament.

A retrospective observational study. To clarify the exceptional conditions for a favorable neurological recovery after laminoplasty (LMP) for cervical myelopathy caused by K-line (-) ossification of the posterior longitudinal ligament (OPLL). The K-line-based classification of cervical OPLL was developed to predict insufficient neurological recovery after LMP. For patients with K-line (-) OPLL, LMP generally yields the least improvement because of inadequate decompression of the spinal cord; however, there are some exceptional cases wherein LMP promotes favorable neurological recoveries. We retrospectively reviewed the medical records of 106 consecutive patients who underwent LMP for cervical OPLL to determine the demographic data, radiographic findings, and neurological recoveries of the patients as assessed preoperatively and 2 years postoperatively by their Japanese Orthopedic Association (JOA) scores. The factors associated with favorable outcomes after LMP in patients with K-line (-) were then investigated. Of 106 total patients, 31 were classified as K-line (-), of whom 21 achieved the least neurological recovery after LMP (JOA recovery rate <50%), while the remaining 10 patients achieved favorable outcomes (JOA recovery rate ≥50%). Among the K-line (-) group patients, those with ext-K-line (+), which changed to K-line (+) in the neck-extended position, and the patients with up-K-line (-), in whom the lesion responsible for myelopathy in the upper cervical spine (C3 or above), showed favorable neurological recoveries after LMP. Our data shows that, even for patients with K-line (-) OPLL, a favorable neurological recovery can be expected after LMP in cases in which the OPLL is in the upper cervical spine or the K-line changes to (+) in the neck-extended position. This means that K-line-based predictions of surgical outcomes after LMP should be indicated for patients with OPLL in the middle and lower cervical spine with limited extension mobility.Level of Evidence: 4.

Accuracy of Pedicle Screw Placement Comparing an Electronic Conductivity Device and a Multi-axis Angiography Unit with C-arm Fluoroscopy in Lumbar Fixation Surgery for Safety.

The aim of this study was to compare the accuracy, safety, and usefulness of percutaneous pedicle screw (PPS) placement for lumbar fixation using a multi-axis angiography unit (MAU) and an electronic conductivity device (ECD) with a cannulated Jamshidi needle with that using a conventional C-arm. Of 65 cases that underwent lumbar fixation (region between L1-S1) during April 2013 to March 2019, 57 cases that could be followed-up for more than 12 months after the procedure were included. Among them, 31 patients (150 screws) received treatment with MAU and ECD (MAU+ECD group) and 26 (117 screws) were treated with the conventional C-arm. We performed a retrospective study of the surgical techniques used in each group at our institute by assessing the accuracy of PPS using Gertzbin–Robbins classification and the Japanese Orthopedic Association (JOA) score for recovery. There was no significant difference in surgery outcome based on the JOA recovery rate. There was a significant difference between the two groups in terms of Accuracy-1 (Group A indicating accuracy and Groups B–E indicating inaccuracy), where the rates were 85.3% and 72.0% in the MAU+ECD group and C-arm group, respectively (P = 0.008). There was also a significant difference between the two groups in terms of Accuracy-2 (Groups A–B indicating accuracy; Groups C–E indicate inaccuracy), where the rates were 98.0% and 92.4% in the MAU+ECD and C-arm groups, respectively (P = 0.036). A combination of MAU and ECD is a safe and accurate method for inserting screws into the pedicle.

Clinical Effects of Anterior Cervical Spondylolisthesis on Cervical Spondylotic Myelopathy After Posterior Decompression Surgery: A Retrospective Multicenter Study of 732 Cases.

Study Design:Multicenter retrospective study.Objectives:We aim to investigate features of cervical spondylotic myelopathy (CSM) associated with anterior cervical spondylolisthesis (ACS) during posterior decompression surgery.Methods:A total of 732 patients with CSM were enrolled, who underwent posterior decompression surgery between July 2011 and November 2015 at 17 institutions. The patients with ACS (group A), defined as an anterior slippage of ≥2 mm on plain radiographs, were compared with those without ACS (group non-A). Also, the characteristics of patients with ACS progression (group P), defined as postoperative worsening of ACS ≥2 mm or newly developed ACS, were investigated. Moreover, kyphosis was defined as C2-C7 angle in neutral position ≤−5°. The Japanese Orthopedic Association (JOA) scoring system was used for clinical evaluation.Results:Group A consisting of 62 patients (8.5%) had worse preoperative clinical status but comparable surgical outcomes to group non-A. Furthermore, ACS was associated with greater age, and the degree of slippage did not affect myelopathy grades. Seventeen patients (2.3%) were observed in group P, and preoperative ACS was a significant predisposing factor for the progression without clinical impact. Among the patients in group A, preoperative cervical kyphosis was a risk factor for lower JOA recovery rate.Conclusions:Although the presence of ACS increases the risk of postoperative progression, it is not a contraindication for posterior decompression. However, surgeons need to consider the indication of fusion surgery for the patients who have ACS accompanied by kyphosis because of the poor surgical outcomes.

Comparison Between the Japanese Orthopaedic Association (JOA) Score and Patient-Reported JOA (PRO-JOA) Score to Evaluate Surgical Outcomes of Degenerative Cervical Myelopathy.

Study Design:A retrospective cohort study.Objective:To investigate whether the Japanese Orthopaedic Association (JOA) score can be used for patients with degenerative cervical myelopathy as a patient-reported outcome (PRO) through the JOA written questionnaire.Methods:A total of 75 patients who underwent posterior decompression surgery for degenerative cervical myelopathy were reviewed. Patients responded to questionnaires including PRO-JOA, EuroQOL-5D, Neck Disability Index, and Short Form-12 preoperatively and at >12 months postoperatively. Spearman’s rho and Bland-Altman analyses were used to investigate the correlations.Results:Preoperative JOA and PRO-JOA scores were 10.8 and 10.6, respectively, with Spearman’s rho of 0.74. Similarly, postoperative JOA and PRO-JOA scores were 13.3 and 12.9, respectively, with Spearman’s rho of 0.68. However, the recovery rates for JOA and PRO-JOA scores were 42% and 27%, respectively, with Spearman’s rho of 0.45. Compared with other PROs, JOA and PRO-JOA scores were moderately correlated. The minimum clinically important difference was 2.5 for JOA score, 3.0 for PRO-JOA score, 42% for JOA recovery rate, and 33% for PRO-JOA recovery rate. Bland-Altman analyses revealed that limits of agreement were −4.3 to 4.7, −3.4 to 4.3, and −75% to 106% for the preoperative score, postoperative score, and recovery rate, respectively.Conclusion:PRO-JOA score can also be used as a disease-specific scoring measure instead of JOA score. However, although both measures demonstrate a similar trend as a group analysis, PRO-JOA and JOA scores should be regarded as different outcomes.

Postoperative changes in spinal cord signal intensity in patients with spinal cord injury without major bone injury: comparison between preoperative and postoperative magnetic resonance images.

Although increased signal intensity (ISI) on MRI is observed in patients with cervical spinal cord injury (SCI) without major bone injury, alterations in ISI have not been evaluated. The association between postoperative ISI and surgical outcomes remains unclear. This study elucidated whether or not the postoperative classification and alterations in MRI-based ISI of the spinal cord reflected the postoperative symptom severity and surgical outcomes in patients with SCI without major bone injury. One hundred consecutive patients with SCI without major bone injury (79 male and 21 female) with a mean age of 55 years (range 20-87 years) were included. All patients were treated with laminoplasty and underwent MRI pre- and postoperatively (mean 12.5 ± 0.8 months). ISI was classified into three groups on the basis of sagittal T2-weighted MRI: grade 0, none; grade 1, light (obscure); and grade 2, intense (bright). The neurological statuses were evaluated according to the Japanese Orthopaedic Association (JOA) scoring system and the American Spinal Injury Association Impairment Scale (AIS). Preoperatively, 8 patients had grade 0 ISI, 49 had grade 1, and 43 had grade 2; and postoperatively, 20 patients had grade 0, 24 had grade 1, and 56 had grade 2. The postoperative JOA scores and recovery rate (RR) decreased significantly with increasing postoperative ISI grade. The postoperative ISI grade tended to increase with the postoperative AIS grade. Postoperative grade 2 ISI was observed in severely paralyzed patients. The postoperative ISI grade improved in 23 patients (23%), worsened in 25 (25%), and remained unchanged in 52 (52%). Patients with an improved ISI grade had a better RR than those with a worsened ISI grade. Postoperative ISI reflected postoperative symptom severity and surgical outcomes. Alterations in ISI were seen postoperatively in 48 patients (48%) and were associated with surgical outcomes.

Is Cervical Disc Replacement Valuable in 3-Level Hybrid Surgery Compared with 3-Level Anterior Cervical Discectomy and Fusion?

Cervical degenerative disc disease is common in clinical practice. Surgery is among the most effective treatments for patients with cervical radiculopathy, myelopathy, or stenosis. Which treatment is the best option for multilevel cervical degenerative disc disease is controversial. Hybrid surgery, combined cervical disc replacement and anterior cervical discectomy and fusion, may be an alternative treatment for multilevel cervical degenerative disc disease. Sixty-four patients with 3-level hybrid surgery and 37 patients with 3-level anterior cervical discectomy and fusion were reviewed retrospectively. Clinical outcomes were based on visual analog scale, Neck Disability Index, 36-Item Short Form Survey, and Japanese Orthopaedic Association scores and Japanese Orthopaedic Association recovery rate. Radiologic assessments included range of motion (ROM) of C2-C7 and adjacent level and cervical lordosis of C2-C7. Perioperative parameters, fusion condition, and complications were assessed. There were no statistical differences observed between the 2 groups for Japanese Orthopaedic Association, Neck Disability Index, or visual analog scale scores. The hybrid surgery group had better physical and mental 36-Item Short Form Survey scores than the fusion group at 1-year follow-up (physical component summary: 49.34 vs. 46.70, P= 0.012; mental component summary: 45.67 vs. 43.95, P= 0.004). ROM of C2-C7 and adjacent levels was less compromised in the hybrid group compared with baseline (64.60% vs. 51.34%, P < 0.001). Cervical lordosis was decreased with time in both groups but was acceptable at final follow-up, and both groups showed solid fusion. Normal ROM and solid fusion were achieved at both arthroplasty and arthrodesis levels. ROM of replacement levels in different locations of the 3-level construct was acceptable.

A prospective randomized cohort study on 3D-printed artificial vertebral body in single-level anterior cervical corpectomy for cervical spondylotic myelopathy.

BackgroundThis was a prospective randomized cohort study aiming at examining the safety and efficacy of artificial vertebral body (AVB) fabricated by electron beam melting (EBM) in comparison to conventional titanium mesh cage (TMC) used in single-level anterior cervical corpectomy and fusion (SL-ACCF).MethodsForty patients with cervical spondylotic myelopathy (CSM) underwent SL-ACCF using either the EBM-AVB or the TMC. Patients were evaluated for their demographics, radiological characteristics, neurologic function [using the Japanese Orthopaedic Association (JOA) scale], and health-related quality-of-life (HRQoL) aspects [using the Short Form 36 (SF-36)] before and after the surgery and comparison was made between the two groups both at baseline and the last follow-up. The Student t-text, paired-sample t-text, and Fisher’s exact test were used when appropriate to detect any statistical significance at the level of α=0.05.ResultsPost-operative recovery was uneventful for all patients and no revision surgery was required. There were no significant differences between the EBM-AVB group and the TMC group at baseline. Patients in both groups demonstrated significant improvement in cervical alignment, JOA score, and SF-36 score after the surgery. Six months post-operatively, patients in the EBM-AVB group were found to have significantly less loss of fusion height and lower incidence for severe implant subsidence compared with the TMC group. Patients in the two groups were comparable at the last follow-up regarding their rate of fusion, cervical alignment, JOA recovery rate, SF-36 score, and by Odom’s criteria.ConclusionsFor CSM patients undergoing SL-ACCF, the EBM-AVB group demonstrated comparable outcomes regarding patient cervical alignment, neurologic function, and HRQoL in comparison with the TMC group. Furthermore, the use of EBM-AVB was associated with decreased loss of the height of the fusion mass and a lower rate for severe implant subsidence.

Microendoscopic decompression for lumbosacral foraminal stenosis: a novel surgical strategy based on anatomical considerations using 3D image fusion with MRI/CT.

Persistent lumbar foraminal stenosis (LFS) is one of the most common reasons for poor postoperative outcomes and is a major contributor to "failed back surgery syndrome." The authors describe a new surgical strategy for LFS based on anatomical considerations using 3D image fusion with MRI/CT analysis. A retrospective review was conducted on 78 consecutive patients surgically treated for LFS at the lumbosacral junction (2013-2017). The location and extent of stenosis, including the narrowest site and associated pathology (bone or soft tissue), were measured using 3D image fusion with MRI/CT. Stenosis was defined as medial intervertebral foraminal (MF; inner edge to pedicle center), lateral intervertebral foraminal (LF; pedicle center to outer edge), or extraforaminal (EF; outside the pedicle). Lumbar (low-back pain, leg pain) and patient satisfaction visual analog scale (VAS) scores and Japanese Orthopaedic Association (JOA) scores were evaluated. Surgical outcome was evaluated 2 years postoperatively. Most instances of stenosis existed outside the pedicle's center (94%), including LF (58%), EF (36%), and MF (6%). In all MF cases, stenosis resulted from soft-tissue structures. The narrowest stenosis sites were localized around the pedicle's outer border. The areas for sufficient nerve decompression were extended in MF+LF (10%), MF+LF+EF (14%), LF+EF (39%), LF (11%), and EF (26%). No iatrogenic pars interarticularis damage occurred. The JOA score was 14.9 ± 2.6 points preoperatively and 22.4 ± 3.5 points at 2 years postoperatively. The JOA recovery rate was 56.0% ± 18.6%. The VAS score (low-back and leg pain) was significantly improved 2 years postoperatively (p < 0.01). According to patients' self-assessment of the minimally invasive surgery, 62 (79.5%) chose "surgery met my expectations" at follow-up. Nine patients (11.5%) selected "I did not improve as much as I had hoped but I would undergo the same surgery for the same outcome." Most LFS existed outside the pedicle's center and was rarely noted in the pars region. The main regions of stenosis were localized to the pedicle's outer edge. Considering this anatomical distribution of LFS, the authors recommend that lateral fenestration should be the first priority for foraminal decompression. Other surgical options including foraminotomy, total facetectomy, and hemilaminectomy likely require more bone resections than LFS treatment. The microendoscopic surgery results were very good, indicating that this minimally invasive surgery was suitable for treating this disease.

The relationship between preoperative cervical sagittal balance and clinical outcome of laminoplasty treated cervical ossification of the posterior longitudinal ligament patients

Laminoplasty is a common surgical method used to treat patients with cervical ossification of the posterior longitudinal ligament (OPLL). Although laminoplasty is preferred over traditional laminectomy, the factors affecting the complications and outcomes are unclear. Recently, sagittal balance indexes have been revealed to be predictors of clinical outcomes in patients with cervical degenerative diseases, but their relationships with laminoplasty-treated OPLL outcomes remains unknown. The purpose of this study is to evaluate the relationship of preoperative cervical sagittal balance indexes and clinical outcome in laminoplasty treated OPLL patients. This is a retrospective case study. Between January 2015 and January 2017, 181 consecutively included patients who underwent cervical laminoplasty for OPLL were enrolled (male:female ratio=126:75; mean age=60.2 years). Cervical spine lateral radiographs in neutral, flexion, and extension positions were taken before and 2 years after the surgery. The C2-C7 Cobb angle, T1 slope, C1-C7 sagittal vertical axis (SVA), C2-C7 SVA, CGH (center of gravity of the head)-C7 SVA, cervical JOA (Japanese Orthopedic Association) score, and neck VAS (visual analogue scale) score were measured preoperatively and postoperatively at the 2-year follow-up. The patients were divided into two groups according to changes in the lordotic angle or the recovery rate of the JOA score. The relationships between the postoperative lordosis loss or the clinical outcome and the preoperative variables, including the patient's age, JOA score, C2-C7 Cobb angle, T1 slope, C1-C7 SVA, C2-C7 SVA, and CGH-C7 SVA, were investigated. The patients were divided into two groups according to the postoperative change in the C2-C7 Cobb angle. There were no differences in the age, preoperative C2-C7 Cobb angle, C1-C7 SVA, or C2-C7 SVA; there was only a difference in the preoperative CGH-C7 SVA and T1 slope level (p=.038, p=.042). The postoperative JOA and JOA recovery rate were related to the postoperative lordosis loss in cervical alignment (p=.048, p=.031). We again divided the patients into two groups according to the JOA recovery rate and found that only the preoperative CGH-C7 SVA and C1-C7 SVA were related to the neurological outcome (p=.011, p=.047). According to the multivariate logistic regression analysis, higher preoperative CGH-C7 SVA levels were significantly associated with decreases in the lordosis angle postoperatively and the clinical outcome (p=.018, OR=1.225; p=.034, OR=1.654). The ROC (receiver operating characteristic) analysis revealed that the proper cutoff value of preoperative CGH-C7 SVA for predicting the postoperative loss of lordosis and clinical outcomes is 3.8 cm. Preoperative cervical sagittal balance indexes are related to the outcomes of OPLL patients after laminoplasty. Patients with high preoperative CGH-C7 SVA levels have a high probability of developing sagittal imbalances and neurological symptoms of the cervical spine, and this measurement can be used as a predictor of outcomes in laminoplasty-treated cervical OPLL patients.