稲毛 一秀

STUDY DESIGN: Controlled laboratory study. PURPOSE: This study aimed to evaluate the efficacy of platelet-rich plasma (PRP) stored at room temperature (RT), frozen, or after freeze-drying. OVERVIEW OF LITERATURE: PRP enriches tissue repair and regeneration, and is a novel treatment option for musculoskeletal pathologies. However, whether biological activity is preserved during PRP storage remains uncertain. METHODS: PRP was prepared from blood of 12 healthy human volunteers (200 mL/person) and stored using three methods: PRP was stored at RT with shaking, PRP was frozen and stored at -80℃, or PRP was freeze-dried and stored at RT. Platelet counts and growth factor content were examined immediately after preparation, as well as 2, 4, and 8 weeks after storage. Platelet activation rate was quantified by flow cytometry. RESULTS: Platelet counts were impossible to determine in many RT samples after 2 weeks, but they remained at constant levels in frozen and freeze-dried samples, even after 8 weeks of storage. Flow cytometry showed approximately 80% activation of the platelets regardless of storage conditions. Almost no growth factors were detected in the RT samples after 8 weeks, while low but significant expression was detected in the frozen and freeze-dried PRP. Over time, the mean relative concentrations of various growth factors decreased significantly or disappeared in the RT group. In the frozen group, levels were maintained for 4 weeks, but decreased significantly by 8 weeks (p <0.05). The freeze-dried group maintained baseline levels of growth factors for the entire 8-week duration. CONCLUSIONS: Freeze-drying enables PRP storage while maintaining bioactivity and efficacy for extended periods.

STUDY DESIGN: Observational study. PURPOSE: To assess the correlation among inflammatory cytokine expression levels, degree of intervertebral disk (IVD) degeneration, and predominant clinical symptoms observed in degenerative disk disease (DDD). OVERVIEW OF LITERATURE: Low back pain (LBP) is associated with inflammatory cytokine expression levels, including those of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and nerve growth factor (NGF). However, the association between cytokine expression levels and the physiological mechanisms of disk degeneration and clinical pain remain controversial. METHODS: Using the enzyme-linked immunosorbent assay, TNF-α, IL-6, and NGF expression levels were analyzed in 58 IVD samples that were harvested from patients with lumbar DDD. Patient samples were grouped according to the degree of IVD degeneration using the Pfirrmann grading system and magnetic resonance imaging, and the correlations between the disease groups and each cytokine expression level were assessed. In addition, on the basis of their predominant preoperative symptoms, the patients were assigned to either an LBP or leg pain group to determine the correlation among these disease manifestations and individual cytokine expression levels. RESULTS: A gradual increase in TNF-α (R=0.391) and IL-6 (R=0.388) expression levels correlated with the degree of IVD degeneration, whereas NGF (R=0.164) expression levels exhibited a minimal decrease with disease progression. Regarding the predominant clinical manifestation, only the LBP group exhibited a significant increase in TNF-α expression levels (p=0.002). CONCLUSIONS: These results suggested that TNF-α and IL-6 play an important role in the pathophysiology of IVD degeneration at any stage, whereas NGF plays an important role during the early disease stages. Moreover, because TNF-α expression levels were significantly high in the LBP group, we propose that they are involved in LBP onset or progression.

整形外科医が多くの患者を抱える、筋骨格・運動器疼痛に対する治療薬は、長らく限られた選択肢しかない状況が続いていた。しかしながら、2010年頃からさまざまな薬剤が市場に投入され、患者の症状に合わせた薬剤選択が可能になりつつある。そのような状況の中で、デュロキセチン(サインバルタ)が2016年3月に「慢性腰痛症に伴う疼痛」の適応症で認証され注目を集めている。そこで本稿ではこのデュロキセチンについて「薬剤の開発の経緯」、「薬剤の特徴(作用機序・薬物動態など)」、「薬剤のエビデンス」、「薬剤の使い方と注意すべき副作用」、「最近のトピックス」を概説する。(著者抄録)

PURPOSE: Recently, it has been reported that impairment by an 8th cervical nerve root lesion can cause drop finger, namely C8 drop finger. Here, we report a clinical case series of C8 drop finger to reveal the clinical outcome of surgical treatments to allow for a better choice of treatment. METHODS: The present study included 17 consecutive patients who were diagnosed as having C8 drop finger, in which muscle strength of the extensor digitorum communis (EDC) showed a manual muscle testing (MMT) grade of 3 or less. We retrospectively investigated the clinical characteristics of C8 drop finger and recovery of muscle power was measured by subtraction of preoperative MMT of the EDC from the final follow-up values. RESULTS: Nine cases showed recovery of muscle power of EDC, whereas the remaining eight cases did not show any recovery including two cases of deterioration. None of the conservatively treated patients showed any recovery. Surgically treated cases included two cases of deterioration. In the cases showing recovery, recovery began 9.9 months after surgery on average and recovery took 13.8 months after surgery on average. There was a significant difference in the recovery of MMT grade between the groups treated conservatively and surgically (p = 0.049). Preoperative MMT grade of EDC showed a moderate correlation with postoperative recovery (r 2 = 0.45, p = 0.003). In other words, the severity of preoperative muscular weakness correlated negatively with postoperative recovery. CONCLUSIONS: C8 drop finger is better treated by surgery than conservative therapy.

STUDY DESIGN: Retrospective, observational, single-center study. PURPOSE: To investigate the long-term outcomes of in situ fusion procedures for treating dysplastic spondylolisthesis. OVERVIEW OF LITERATURE: In situ fusion performed in patients with dysplastic spondylolisthesis avoids the development of nerve complications. METHODS: In total, 12 of 28 patients who underwent in situ fusion for treating dysplastic spondylolisthesis at Chiba University Hospital from 1974 to 2004 were followed up in August 2013. Surgical complications were evaluated. Low back pain and leg pain were assessed using a visual analog scale (VAS). Vertebral alignment, including the lumbosacral angle and lumbar lordosis angle measurement on radiographic images (profile view in the neutral standing position), was evaluated during preoperative, postoperative, and final examinations. RESULTS: The mean follow-up duration, patient age at the final examination, and patient age at operation were 20.0±7.2, 42.3±13.3, and 22.3±11.4 years, respectively. No complications were reported. Mean VAS scores for low back pain and leg pain were significantly lower at the final examination than at the preoperative examination (p<0.05). At the preoperative, postoperative, and final examinations, the mean lumbosacral angle was 32.3°±14.2°, 33.7°±11.8°, and 36.5°±16.4°, while the mean lumbar lordosis angle was 51.0°±14.8°, 48.6°±18.8°, and 49.6°±15.5°, respectively. No significant differences were noted among these values across the different time periods (p<0.05). CONCLUSIONS: In situ fusion performed in patients with dysplastic spondylolisthesis avoids the development of nerve complications such as nerve paralysis that may occur after repositioning operation and maintains appropriate long-term sagittal alignment, even 20 years after operation.

STUDY DESIGN: Retrospective case series. PURPOSE: The purpose of this study was to determine whether discontinuing teriparatide treatment and replacing it with bisphosphonate treatment maintains the volume of the fusion mass after posterolateral fusion (PLF) in women with postmenopausal osteoporosis. OVERVIEW OF LITERATURE: Clinical data support the efficacy of parathyroid hormone (PTH) for lumbar PLF. However, the use of PTH is limited to 2 years. METHODS: We treated 19 women diagnosed with osteoporosis and degenerative spondylolisthesis with teriparatide (20 µg daily subcutaneously). All patients underwent one-level instrumented PLF. Teriparatide was used during 2 months prior to surgery and more than 8 months after surgery. After discontinuing teriparatide treatment, all patients used bisphosphonate (17.5 mg risedronate weekly, oral administration). Area of the fusion mass across the transverse processes at one segment was determined on an anteroposterior radiograph at 1, 2, and 3 years after surgery. RESULTS: We followed 19 patients for 3 years. The average duration of teriparatide treatment was 11.5 months. The bone union rate was 95%. The average area of the bone fusion mass was not significantly different between the right and left sides at 1, 2, or 3 years after surgery (p>0.05). CONCLUSIONS: This study showed that replacing teriparatide treatment with bisphosphonate maintained the bone fusion mass volume after PLF in women with postmenopausal osteoporosis.

PURPOSE: Extreme lateral interbody fusion provides minimally invasive treatment of spinal deformity, but complications including nerve and psoas muscle injury have been noted. To avoid nerve injury, mini-open anterior retroperitoneal lumbar interbody fusion methods using an approach between the aorta and psoas, such as oblique lumbar interbody fusion (OLIF) have been applied. OLIF with percutaneous pedicle screws without posterior decompression can indirectly decompress the spinal canal in lumbar degenerated spondylolisthesis. In the current study, we examined the radiographic and clinical efficacy of OLIF for lumbar degenerated spondylolisthesis. METHODS: We assessed 20 patients with lumbar degenerated spondylolisthesis who underwent OLIF and percutaneous pedicle screw fixation without posterior laminectomy. MR and CT images and clinical symptoms were evaluated before and 6 months after surgery. Cross sections of the spinal canal were evaluated with MRI, and disk height, cross-sectional areas of intervertebral foramina, and degree of upper vertebral slip were evaluated with CT. Clinical symptoms including low back pain, leg pain, and lower extremity numbness were evaluated using a visual analog scale and the Oswestry Disability Index before and 6 months after surgery. RESULTS: After surgery, significant increases in axial and sagittal spinal canal diameter (12 and 32 %), spinal canal area (19 %), disk height (61 %), and intervertebral foramen areas (21 % on the right side, 39 % on the left), and significant decrease of upper vertebral slip (-9 %) were found (P < 0.05). Low back pain, leg pain, and lower extremity numbness were significantly reduced compared with before surgery (P < 0.05). CONCLUSIONS: Significant improvements in disk height and spinal canal area were found after surgery. Bulging of disks was reduced through correction, and stretching the yellow ligament may have decompressed the spinal canal. Lumbar anterolateral fusion without laminectomy may be useful for lumbar spondylolisthesis with back and leg symptoms.