Persistence of Denosumab Therapy among Patients with Osteoporosis

Kobayashi Kazuyoshi,Ando Kei,Machino Masaaki,Morozumi Masayoshi,Kanbara Shunsuke,Ito Sadayuki,Inoue Taro,Yamaguchi Hidetoshi,Ishiguro Naoki,Imagama Shiro 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.4

Study Design: Retrospective study in a single center.Purpose: To examine denosumab persistence in patients of different ages with severe osteoporosis in Japan.Overview of Literature: Denosumab is an antibody drug used for the treatment of osteoporosis. It is mainly used in patients with severe osteoporosis who might have high motivation for treatment, and the need for only semi-annual subcutaneous injection might improve the continuation rate. However, no English-language articles have reported on denosumab persistence in the Japanese population, including young people, despite the importance of this issue in a super-aging society. Methods: The subjects started treatment with subcutaneous denosumab in our department from July 2013 until December 2017. Persistence rates were calculated using Kaplan-Meier curves. Patients were defined as “persistent” or “non-persistent” according to the use of therapy after 60 months.Results: The study included 101 patients (84 females) with a median follow-up period of 23.6±14.2 months. The persistence rate declined to 85.3%, 78.3%, 74.1%, 71.3%, and 69.3% at 12, 24, 36, 48, and 60 months, respectively. Age at the initiation of denosumab therapy differed significantly between non-persistent (n=31) and persistent (n=70) patients (81.3 vs. 72.8 years, <i>p</i> <0.01). Persistence was significantly lower in patients aged ≥80 years than in those aged <60 and 60–79 years (both <i>p</i> <0.01). The reasons for non-persistence of denosumab therapy were transfer to another hospital (n=13), interruption of outpatient visits (n=11), dental treatment (n=4), adverse events (n=2), and patient request (n=1).Conclusions: Persistence was significantly lower in patients aged ≥80 years than in patients of other ages, and strategies promoting persistence are needed for these elderly patients.

Efficacy of Anal Needle Electrodes for Intraoperative Spinal Cord Monitoring with Transcranial Muscle Action Potentials

Kazuyoshi Kobayashi,Kei Ando,Hideki Yagi,Kenyu Ito,Mikito Tsushima,Masayoshi Morozumi,Satoshi Tanaka,Masaaki Machino,Kyotaro Ota,Yukihiro Matsuyama,Naoki Ishiguro,Shiro Imagama 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.4

Study Design: Retrospective study. Purpose: To examine the relationship between postoperative bowel bladder disorder (BBD) and the efficacy of needle electrodes for the external anal sphincter (EAS) in intraoperative spinal cord monitoring with transcranial muscle action potentials (Tc-MsEP). Overview of Literature: Spinal surgery for spina bifida, spinal cord tumor, and spinal tethered cord syndrome has a high rate of postoperative BBD. Monitoring of the EAS with Tc-MsEP is frequently performed during spinal surgery. We initially used plug-surface electrodes for this purpose, but have more recently switched to needle electrodes for the monitoring of the EAS. To date, there has been no comparison between the utility of these electrodes. Methods: Waveform derivation, exacerbation of postoperative BBD, and sensitivity and specificity for prediction of BBD by 70% amplitude reduction of EAS activity using needle and plug-surface electrodes were investigated in 239 spine surgeries. The cut-off for the % drop in amplitude for BBD prediction was determined for EAS monitoring using a needle electrode. Results: The overall rate of postoperative BBD aggravation was 7.1% (17/239 cases), with the individual rates using needle and plug-surface electrodes being 6.9% (8/116) and 7.3% (9/123), respectively. The waveform derivation rate was significantly higher using needle electrodes (91.3% [106/116] vs. 76.4% [94/123], p <0.01). In patients with baseline waveform detection, the sensitivity and specificity for postoperative BBD were similar in the two groups. With needle electrodes, a cutoff amplitude of Tc-MsEP for the EAS at the end of surgery of 25% of the baseline amplitude had a sensitivity of 89% and specificity of 82% for the prediction of postoperative BBD aggravation. Conclusions: The significantly higher waveform derivation rate using needle electrodes suggests that these electrodes are effective for monitoring the EAS in spinal surgery in cases with preoperative BBD.

Scoliosis Caused by Limb-Length Discrepancy in Children

Kobayashi Kazuyoshi,Ando Kei,Nakashima Hiroaki,Machino Masaaki,Morozumi Masayoshi,Kanbara Shunsuke,Ito Sadayuki,Inoue Taro,Yamaguchi Hidetoshi,Mishima Kenichi,Ishiguro Naoki,Imagama Shiro 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.6

Study Design: Single-center retrospective study in pediatric patients.Purpose: The purpose of the study was to investigate the effects of the presence and severity of leg-length discrepancy (LLD) on scoliosis in children.Overview of Literature: LLD is a common orthopedic problem that can result in standing imbalance, low back pain, and stress fractures. It may cause structural changes in the spine over time, but the exact effect of LLD on scoliosis is unknown.Methods: The subjects were 23 children with LLD ≥20 mm (range, 27–65 mm) treated at Nagoya University Hospital between 2007 and 2017. Whole spine posteroanterior standing radiographs and whole lower limb radiographs in a supine position were recorded. Data were collected for demographics, LLD, Cobb angle, pelvic obliquity, and Nash/Moe index. Scoliosis was defined as a Cobb angle ≥10°. Leg length was measured from the top of the femoral head to the middle of the tibial plafond, and LLD was defined as the difference between the left and right leg lengths.Results: The patients (nine males and 14 females) had a mean age of 14.0 years (range, 5–18 years). The average LLD was 44.3±17.2 mm, with LLDs of 20 to 39 mm, 40 to 59 mm, and ≥60 mm in 13, five, and five subjects, respectively. The average Cobb angle was 13.0°±7.0°, and 15 subjects (65%) had scoliosis. Convexity of the scoliosis was to the short leg side in all cases. The Cobb angle was significantly related to the severity of the LLD (<i>R</i>=0.736, <i>p</i><0.01), pelvic obliquity (<i>R</i>=0.966, <i>p</i><0.01), and Nash/Moe index (<i>p</i><0.05).Conclusions: LLD is a common pediatric condition that can cause scoliosis of the spine. Severe scoliosis may develop if the LLD is ≥30 mm. Long-term studies are needed to examine the effect of LLD resolution on the elimination of scoliosis.

Perioperative Management of Patients with Hemophilia during Spinal Surgery

Kazuyoshi Kobayashi,Shiro Imagama,Kei Ando,Kenyu Ito,Mikito Tsushima,Masayoshi Morozumi,Satoshi Tanaka,Masaaki Machino,Kyotaro Ota,Yoshihiro Nishida,Naoki Ishiguro 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.3

Study Design: Single-center retrospective study. Purpose: To optimize the perioperative management of patients with hemophilia who are undergoing spinal surgery. Overview of Literature: Hemophilia is a rare disease in which there is a tendency of bleeding because of a congenital deficiency in blood coagulation factor activity. There has been no previous report on spinal surgery in patients with hemophilia. Methods: The subjects were five patients (all males) with hemophilia who underwent spinal surgery at Nagoya University Hospital. Two patients had hemophilia A (deficiency of factor VIII) and three had hemophilia B (deficiency of factor IX). The mean age at the time of surgery was 63 years (range, 46–73 years). The following surgeries were performed: posterior lumbar interbody fusion (PLIF) in two patients, and lumbar fenestration, cervical laminoplasty and lumbar fenestration, and cervical laminoplasty and PLIF in one patient each. Results: Coagulation factor at a mean dose of 4.8 ×103 U (range, 3–6 ×103 U) was intravenously injected before surgery, and a mean dose of 5.2 ×103 U (rang, 4–6 ×103 U) was continuously administered for 24 hours after surgery. Factor activity was maintained at ≥80% until postoperative day 14 and at ≥50% thereafter. The average duration of surgery was 178 minutes (range, 133–233 minutes), the estimated blood loss was 661 mL (range, 272–1,344 mL), and a drain tube was left subfascially in place for 2 days in all patients. Reoperation due to postoperative surgical site infection was required in one patient, but there were no complications due to hemorrhagic diathesis. The total dose of coagulation factor administered during hospitalization was 102 ×103 U (range, 46–198 ×103 U). Conclusions: Coordination with a hematologist and dose adjustment of the coagulation factor preparation to maintain a target level of coagulation factor activity facilitated a smooth postoperative course with perioperative control of bleeding during spinal surgery for patients with hemophilia.

Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model

Zenya Ito,Shiro Imagama,Kei Ando,Akio Muramoto,Kazuyoshi Kobayashi,Tetsuro Hida,Kenyu Ito,Yoshimoto Ishikawa,Mikito Tsushima,Akiyuki Matsumoto,Satoshi Tanaka,Masayoshi Morozumi,Yukihiro Matsuyama,Naok 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.6

Study Design: Animal study. Purpose: To review the present warning point criteria of the compound muscle action potential (CMAP) and investigate new criteria for spinal surgery safety using an animal model. Overview of Literature: Little is known about correlation palesis and amplitude of spinal cord monitoring. Methods: After laminectomy of the tenth thoracic spinal lamina, 2–140 g force was delivered to the spinal cord with a tension gage to create a bilateral contusion injury. The study morphology change of the CMAP wave and locomotor scale were evaluated for one month. Results: Four different types of wave morphology changes were observed: no change, amplitude decrease only, morphology change only, and amplitude and morphology change. Amplitude and morphology changed simultaneously and significantly as the injury force increased (p <0.05) Locomotor scale in the amplitude and morphology group worsened more than the other groups. Conclusions: Amplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP.