Quantitative Assessment of Bone Marrow Edema in Adolescent Athletes with Lumbar Spondylolysis Using Contrast Ratio on Magnetic Resonance Imaging

Nakamae Toshio,Kamei Naosuke,Tamura Takayuki,Kanda Tsukasa,Nakanishi Kazuyoshi,Adachi Nobuo 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.5

Study Design: Prospective cohort study. Purpose: To quantitatively evaluate bone marrow edema (BME) in the pedicle on magnetic resonance imaging (MRI) for adolescent athlete patients with spondylolysis. Overview of Literature: Spondylolysis, a stress fracture of the pars interarticularis, is a common occurrence in adolescent athletes with low back pain. T2-weighed fat-saturated MRI is reportedly useful for the detection of BME in the pedicle in the early stage of spondylolysis; however, to our knowledge, the quantitative assessment of BME in spondylolysis has not been reported. Methods: Adolescent athletes with spondylolysis, including those with symptoms of low back pain, were enrolled. The sporting activity of the patients was restricted, and a hard brace was attached to the spine. The BME range of interest was taken on T2-weighed fat-saturated MRI, and the signal intensity (SI) of the BME (SIedema) was measured. The contrast ratio (CR) between the SI of the BME and SI of the spinal cord (SIcord) was calculated per the following formulae: CRedema=(SIedema–SIcord)/(SIedema+SIcord). The CR of the normal pedicle was measured as a control per the following formulae: CRcontrol=(SIcontrol–SIcord)/(SIcontrol+SIcord). Results: The study enrolled 32 men and one woman; the mean patient age was 15.2 years (range, 12–18 years). The average CR of the edema and normal pedicle at the first visit was 0.506 (range, 0.097–0.804) and 0.137 (range, -0.741 to 0.572), respectively. The CR of the edema was significantly higher as compared to that of the normal pedicle (p<0.01). MRI that was performed 1 month after the first visit showed that the CR of the edema had decreased to 0.204 (range, -0.152 to 0.517). The CR of the edema 1 month thereafter was significantly lower than that at the first visit (p<0.01). Conclusions: Quantitative assessment of BME using CR on MRI is useful in the evaluation of the healing process of spondylolysis.

Quantifying Bone Marrow Edema Adjacent to the Lumbar Vertebral Endplate on Magnetic Resonance Imaging: A Cross-Sectional Study of Patients with Degenerative Lumbar Disease

Nakamae Toshio,Kamei Naosuke,Fujimoto Yoshinori,Yamada Kiyotaka,Tamura Takayuki,Tsuchikawa Yuji,Morisako Taiki,Harada Takahiro,Maruyama Toshiaki,Adachi Nobuo 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.2

Study Design: Cross-sectional study. Purpose: We aimed to quantitatively assess bone marrow edema (BME) on magnetic resonance imaging (MRI) for patients with degenerative lumbar diseases. Overview of Literature: BME adjacent to a sclerotic endplate of the lumbar spine, detected using T2-weighted fat-saturated MRI, is closely associated with low back pain in patients with degenerative lumbar diseases. However, currently, there no quantitative evaluation methods for BME adjacent to the vertebral endplate. Methods: Patients with degenerative lumbar diseases, whose MRIs detected BME, were enrolled. On a T2-weighted fat-saturated MRI, BME appeared as a high-intensity region adjacent to the vertebral endplate. We calculated the contrast ratios (CRs) of BME and normal bone marrow using the signal intensities of BME, normal bone marrow, and the spinal cord. On computed tomography, we calculated Hounsfield unit (HU) values in the same area as BME, the sclerotic endplate, and normal bone marrow to assess bone density. Results: There were 16 men and 14 women, with an average age of 73.5 years. The mean CRs of BME and normal bone marrow were −0.015±0.056 and −0.407±0.023, respectively. BME’s CR was significantly higher than that of normal bone marrow (p<0.01). The HU values in the same area as BME, the sclerotic endplate, and normal bone marrow were 251.9±24.6, 828.3±35.6, and 98.1±9.3, respectively; these values were significantly different from each other (p<0.01). Conclusions: The CR on MRI is a useful quantitative assessment tool for BME in patients with degenerative lumbar diseases.

Risk Factors for Cement Loosening after Vertebroplasty for Osteoporotic Vertebral Fracture with Intravertebral Cleft: A Retrospective Analysis

Toshio Nakamae,Kiyotaka Yamada,Yasuyuki Tsuchida,Orso Lorenzo Osti,Nobuo Adachi,Yoshinori Fujimoto 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.5

Study Design: Retrospective case-control study. Purpose: To evaluate the primary outcomes and radiographic results of percutaneous vertebroplasty (PVP) in patients with singlelevel osteoporotic vertebral fracture (OVF) with intravertebral cleft (IVC) to identify the risk factors for cement loosening after PVP. Overview of Literature: PVP is a widely accepted method for managing painful OVF; however, cement loosening occasionally occurs with poor outcomes. Methods: This retrospective study involved 195 patients treated with PVP for single-level OVF with IVC. Six months thereafter, the primary outcomes were evaluated using the Visual Analog Scale (VAS) for back pain and the modified Oswestry Disability Index. Computed tomography was conducted to detect cement loosening. Possible risk factors, such as age, sex, wedging angle, intravertebral instability, Parkinson’s disease, spinous process fracture, ankylosing spinal hyperostosis, split vertebrae, and adjacent intervertebral vacuum, were assessed. Results: Forty-nine patients (25%) experienced cement loosening 6 months after PVP. The mean VAS scores were significantly higher in patients with cement loosening than in those without (50 vs. 26 mm, respectively; p <0.01). Cement loosening was closely associated with intravertebral instability (odds ratio [OR], 1.20; 95% confidence interval [CI], 1.04–1.40; p =0.015), Parkinson’s disease (OR, 54.31; 95% CI, 4.47–659.53; p =0.002), spinous process fracture (OR, 7.11; 95% CI, 1.65–30.60; p =0.009), and split vertebrae (OR, 11.59; 95% CI, 1.64–82.02; p =0.014). Conclusions: Patients with cement loosening experienced worse back pain than those without cement loosening. The important risk factors that influenced cement loosening after PVP were high intravertebral instability, Parkinson’s disease, spinous process fracture, and split vertebrae.

Foramen Magnum Decompression with Outer Dura Matter Layer Resection for Chiari Type I Malformation: Factors Correlated with Syrinx Reduction

Maruyama Toshiaki,Nakamae Toshio,Kamei Naosuke,Tanaka Nobuhiro,Fujiwara Yasushi,Harada Takahiro,Adachi Nobuo 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.2

Study Design: A retrospective cohort study.Purpose: We aimed to investigate the surgical results of foramen magnum decompression (FMD) to identify the potential factors associated with syrinx reduction in Chiari malformation type I (CMI).Overview of Literature: The predictive value of preoperative factors for syrinx reduction in patients with CMI remains debatable.Methods: We enrolled patients who underwent microscopic FMD with outer dural layer resection for CMI. The distance from the tip of the cerebellar tonsil to the C2 vertebral endplate on sagittal magnetic resonance imaging (MRI) was defined as the tonsillar distance (TD). Patients who showed a >20% syrinx diameter reduction on the 1-year follow-up MRI were defined as the syrinx reduction group while the others were categorized in the syrinx nonreduction group. Patients with syringomyelia were categorized into the clinically improved and unimproved groups using the Chicago Chiari Outcome Scale. The imaging and clinical parameters were evaluated pre- and postoperatively.Results: This study included 25 patients of whom 19 (76.0%) had syringomyelia. At the 1-year follow-up, the syrinx diameter had decreased in 11 patients (57.8%). The increased TD significantly differed between the syrinx reduction and nonreduction groups. At the 1-year follow-up, 12 and seven patients with syringomyelia were categorized into the clinically improved and unimproved groups, respectively. The clinically improved and unimproved groups showed significant differences in the mean age and increased TD.Conclusions: Postoperative syrinx reduction was significantly correlated with the upward shifting of the cerebellar tonsil in patients with CMI. Our quantitative evaluation of the alterations in hindbrain position after FMD was easily performed and reflects the clinical outcomes.

Physical Signs and Clinical Features of Cervical Myelopathy in Elderly Patients, Especially 80 Years or Older: Comparison of 100 Consecutive Operative Cases across Three Age Groups

Hamasaki Takahiko,Nakamae Toshio,Kamei Naosuke,Fujiwara Yasushi,Rhee John M.,Tanaka Nobuhiro,Fujimoto Yoshinori,Adachi Nobuo,Shimose Shoji 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.5

Study Design: Retrospective cohort study.Purpose: The present study aimed to examine the characteristics of physical signs in elderly patients with cervical myelopathy (CM) and to compare the findings in three different age groups.Overview of Literature: As the global population ages, the incidence of CM in elderly patients is increasing.Methods: We evaluated 100 consecutive surgical patients with CM and divided them into the following groups: 80s (34 patients; mean age, 83.9 years), 70s (33 patients; mean age, 73.9 years), and 69 or younger (33 patients; mean age, 60.9 years). The clinical symptoms and physical signs were evaluated and recorded.Results: Although the recovery rate decreased with increasing age, all groups demonstrated a significant improvement in clinical symptoms relative to preoperative values. The Hoffman sign and hyperreflexia of the triceps tendon were, respectively, present in 82% and 88% of patients in the 80s group, 74% and 64% of those in the 70s group, and 69% and 82% of those in the 69 or younger group, with no significant difference among the groups. In contrast, the rates of hyperreflexia of the patellar and Achilles tendons were, respectively, 59% and 32% in the 80s group, 85% and 48% in the 70s group, and 91% and 70% in the 69 or younger group, with significant differences.Conclusions: The positivity rate of the lower extremity hyperreflexia decreased significantly with increasing age in patients with CM. The absence of hyperreflexia, particularly lower extremity, is not uncommon in elderly patients with suspected CM.

Novel Hybrid Hydroxyapatite Spacers Ensure Sufficient Bone Bonding in Cervical Laminoplasty

Nobuhiro Tanaka,Kazuyoshi Nakanishi,Naosuke Kamei,Toshio Nakamae,Shinji Kotaka,Yoshinori Fujimoto,Mitsuo Ochi,Nobuo Adachi 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.6

Study Design: Prospective observational study. Purpose: This prospective analysis aimed to evaluate the efficacy and bone-bonding rate of hybrid hydroxyapatite (HA) spacers in expansive laminoplasty. Overview of Literature: Various types of spacers or plates have been developed for expansive laminoplasty. Methods: Expansive open-door laminoplasty was performed in 146 patients with cervical myelopathy; 450 hybrid HA spacers and 41 autogenous bone spacers harvested from the spinous processes were grafted into the opened side of each lamina. The patients were followed up using computed tomography (CT), and their bone-bonding rates for hybrid HA and autogenous spacers, bone-fusion rates of the hinges of the laminae, and complications associated with the implants were then examined. Results: Clinical symptoms significantly improved in all patients, and no major complications related to the procedure were noted. The hybrid HA spacers exhibited sufficient bone bonding on postoperative CT. The hinges completely fused in over 95% patients within 1 year of the procedure. Only 4 spacers (0.9%) developed lamina sinking, and most expanded laminae maintained their positions without sinking or floating throughout the follow-up period. Conclusions: Hybrid HA spacers contributed to high bone-fusion rates of the spacers and hinges of the laminae, and no complications were associated with their use. Cervical laminoplasty with these spacers is safe and simple, and it yields sufficient fixation strength while ensuring sufficient bone bonding during the immediate postoperative period.