Takashi Chikawa

Preventive effects of lecithinized superoxide dismutase and methylprednisolone on spinal cord injury in rats: Transcriptional regulation of inflammatory and neurotrophic genes

The effects of lecithinized superoxide dismutase (PC-SOD) and/or methylpredisolone (MP) in preventing secondary pathological changes after spinal cord injury (SCI) were investigated in rats with reference to recovery of hindlimb motor function and expression of mRNA of pro-inflammatory and neurotrophic genes. Hindlimb motor function was assessed as the BBB open field locomotor scores. The BBB scores of three groups treated with either PC-SOD (40,000 units/kg), MP (30 mg/kg), or a combination of PC-SOD and MP (PC-SOD+MP) increased with time until 3 days after SCI, and were significantly higher than that of the control group (p < 0.05). Thereafter, the score of the PC-SOD group increased, whereas that of the MP group showed a temporary decrease from day 3 to 5 and then it gradually recovered. The scores in all groups reached a plateau about 18 days after SCI. The PC-SOD+MP group did not show a synergism but a tendency similar to that of the MP group. PC-SOD and MP had down-regulatory effects on mRNA expression of pro-inflammatory substances such as interleukin-1beta (IL-1beta), intercellular adhesion molecule-1 (ICAM-1), and inducible-nitric oxide synthetase (i-NOS) after spinal cord compression at 3, 6, and 24 h, respectively, as judged by a semiquantitative reverse transcription-polymerase chain reaction and on the lipid peroxide (LPO) level 1 h after injury as determined by thiobarbituric acid-reactive substances. The suppression of pro-inflammatory genes expression, especially IL-1beta were greater in the MP group than in the PC-SOD group, while suppression of LPO level was similar in these two groups. PC-SOD+MP treatment augmented the suppression of all three pro-inflammatory genes expression and the decrease of the LPO level. The level of neurotrophin-3 (NT-3) mRNA increased from 6 h after SCI and reached a maximum after 48 h. NT-3 mRNA level was enhanced by PC-SOD treatment, but not by MP treatment. Thus, the effect of MP in suppressing these pro-inflammatory genes expression was more than that of PC-SOD. The difference in motor function in the early and later stage may be partially due to differences in expression of IL-1beta and NT-3 after either treatment, through an IL-1beta-dependent or NT-3-mediated repair response.

Retrospective study of deep surgical site infections following spinal surgery and the effectiveness of continuous irrigation

Surgical site infection (SSI) is an unfortunate and unpreventable complication of any surgical intervention including spinal surgery. Early deep SSI (EDSSI) after instrumented spinal fusion are particularly difficult to manage due to the implanted, and possibly infected, instrumentation. The purpose of this study is to retrospectively review patients who underwent spinal surgery, investigate the rate of EDSSI, identify patient-related and surgery-related risk factors and to assess the effectiveness of continuous indwelling irrigation on the eradication of these infections. A total of 814 patients (319 women and 495 men) who underwent spinal surgery were enrolled. Mean age at the initial surgery was 57.4 years old. Infections that penetrated the deep fascia within 1 month after the initial operation were considered as EDSSI. The rate of EDSSI, causal organisms, infection management and resolution were studied. Furthermore, we examined the patient-related and the operation-related risk factors. An overall incidence of EDSSI of 1.1% was found. In 177 patients with diabetes mellitus (DM), two patients (1.1%) developed EDSSI. In 28 patients receiving chronic haemodialysis (HD), two patients with infections (7.1%) were identified, which was statistically significantly greater than the other patient populations. Both operative time and intraoperative blood loss were significantly greater in patients with EDSSI than in non-infected patients. Furthermore, the rate of EDSSI in patients undergoing instrumented spinal fusion (3.8%) was significantly higher than that in the other patients. In the nine patients who developed EDSSI, the causal organisms were identified and treated by surgical debridement, antibiotic therapy and continuous indwelling surgical site irrigation. All infections resolved, and no recurrence has been observed at final follow-up. Removal of the instrumentation was required in only one patient. Based on our results, we believe that continuous surgical site irrigation is an effective adjunct in the surgical treatment for early SSI following spinal surgery.

Clinical outcomes of spinal surgery in patients treated with hemodialysis.

Study Design: Retrospective study. Objective: The purpose of this study is to review clinical outcomes, including survival rate, and to discuss the potential benefit of surgical treatments for spinal disorders in patients treated with long-term hemodialysis (HD). Summary of Background Data: Long-term HD is known to possibly cause destructive spondyloarthropathy (DSA) with spinal canal stenosis. There have been few reports, however, regarding clinical outcomes and patient survival rates after spinal surgeries in this population. Methods: We retrospectively reviewed 33 chronic HD patients who underwent 21 cervical and 13 lumbar spinal surgeries. According to the radiologic findings, we divided them into the non-DSA and the DSA groups. In general, only decompression was performed for the non-DSA patients, whereas spinal fusion was added for the DSA patients. We analyzed the following data, respectively: male-female ratio, age, operative time, estimated blood loss, duration of HD, follow-up duration, preoperative and postoperative Japanese Orthopaedic Association score, improvement ratio of the Japanese Orthopaedic Association score, amyloid deposition characteristics, and survival rate. Results: All patients improved neurologically and functionally after surgery. There were significant differences in the operative time between the DSA and the non-DSA groups in patients with cervical spinal lesions, whereas in patients with lumbar spinal lesions, there were significant differences in sex, operative time, and estimated blood loss. Amyloid deposition was found signficantly more commonly in DSA than in non-DSA patients and was associated with a longer duration of HD. Nine patients died within 49 months of the surgery because of HD-related complications, but there was no surgery-related morbidity. Kaplan-Meier analysis showed a trend toward decreased survival rate in non-DSA patients more than 40 months after the index surgery. Conclusions: Even in patients treated with long-term HD, spinal surgeries reliably obtain neurological and functional improvement if surgeons judge the preoperative inclusion criteria correctly. However, if surgeries are necessary for these patients, surgeons should consider the patients’ comorbidity-related survival rate after the spinal surgeries.

State-of-the-art transforaminal percutaneous endoscopic lumbar surgery under local anesthesia: Discectomy, foraminoplasty, and ventral facetectomy

Transforaminal (TF) percutaneous endoscopic surgery for the lumbar spine under the local anesthesia was initiated in 2003 in Japan. Since it requires only an 8-mm skin incision and damage of the paravertebral muscles would be minimum, it would be the least invasive spinal surgery at present. At the beginning, the technique was used for discectomy; thus, the procedure was called PELD (percutaneous endoscopic lumbar discectomy). TF approach can be done under the local anesthesia, there are great benefits. During the surgery patients would be in awake and aware condition; thus, severe nerve root damage can be avoided. Furthermore, the procedure is possible for the elderly patients with poor general condition, which does not allow the general anesthesia. Historically, the technique was first applied for the herniated nucleus pulposus. Then, foraminoplasty, which is the enlargement surgery of the narrow foramen, became possible thanks to the development of the high speed drill. It was called the percutaneous endoscopic lumbar foraminoplasty (PELF). More recently, this technique was applied to decompress the lateral recess stenosis, and the technique was named percutaneous endoscopic ventral facetectomy (PEVF). In this review article, we explain in detail the development of the surgical technique of with time with showing our typical cases.

Incidence and clinical features of sacral insufficiency fracture in the emergency department

Introduction: A sacral insufficiency fracture (SIF) often manifests as low back pain or sciatica in the absence of any antecedent trauma. These fractures may be missed because of lack of appropriate imaging. The purpose of this study was to clarify the incidence and clinical features of SIF as well as the characteristic findings on magnetic resonance imaging (MRI) of the lumbar spine. Materials and methods: The study participants comprised 250 patients (132 male, 118 female; mean age 58.6 years) with pelvic trauma. SIF was identified on computed tomography or MRI. The incidence, initial symptoms, and time delay between the first visit and an accurate diagnosis of SIF were recorded. Results: We detected 11 cases of SIF. Initial symptoms of SIF were low back pain (36.4%), gluteal pain (63.6%), and coxalgia (18.2%). Two patients complained of both low back pain and gluteal pain. The mean delay between the first visit and an accurate diagnosis of SIF was 23.9 days. This time interval was significantly longer than in patients with other types of pelvic fracture. Four patients underwent MRI targeting the lumbar spine to investigate their symptoms. In all 4 patients, the signal intensity on T1‐weighted and fat‐suppressed images of the second sacral segment was low and high, respectively. Conclusion: This study demonstrates that accurate diagnosis of SIF may be delayed because of difficulties in detecting this type of fracture on plain X‐ray and the non‐specific nature of the presenting complaints. Emergency physicians should keep SIF in mind when investigating patients who complain of low back pain or gluteal pain. Findings at the second sacral segment on MRI targeting the lumbar spine may aid early diagnosis of this type of pelvic fracture.

Intradural lumbar disc herniation after percutaneous endoscopic lumbar discectomy: case report

A 64-year-old man was referred to the authors with low-back pain (LBP) and right leg pain with a history of previously diagnosed lumbar disc herniation (LDH) at L4-5. He had undergone 2 percutaneous endoscopic lumbar discectomies (PELDs) for the herniation at another institution, and according to the surgical record of the second surgery, a dural tear occurred intraoperatively but was not repaired. Postoperative conservative treatments such as an epidural block and blood patch had not relieved his persistent LBP or right leg pain. Upon referral to the authors, MRI and myelography revealed an intradural LDH. The herniated mass was removed by durotomy, and posterior lumbar interbody fusion was performed. His symptoms were partially improved after surgery. Primary suture is technically difficult when a dural tear occurs during PELD. Therefore, close attention should be paid to avoiding such tears, and surgeons should increase their awareness of intradural LDH as a possible postoperative complication of PELD.

A new concept of transforaminal ventral facetectomy including simultaneous decompression of foraminal and lateral recess stenosis: Technical considerations in a fresh cadaver model and a literature review

Percutaneous endoscopic surgery for the lumbar spine, which was established in the last decade, requires only an 8-mm skin incision and causes minimal damage to the paravertebral muscles; thus, it is considered to be a minimally invasive technique for spinal surgery. It has been used to perform percutaneous endoscopic discectomy via two main approaches: the TF approach is a posterolateral one through the intervertebral foramen and can be done under local anesthesia; the IL approach is a more traditional one through the interlaminar space and is difficult to perform under local anesthesia. Recently, these techniques have been applied for lumbar spinal stenosis (LSS), the TF method for foraminal stenosis under local anesthesia, and the IL method for central and lateral recess stenosis under general anesthesia. In this study, using a fresh human cadaver model, we performed simultaneous decompression of the lateral recess and foraminal stenosis at L4-5 using the TF approach. Computed tomography confirmed enlargement of the lateral recess and intervertebral foramen. This technique, which can be performed under local anesthesia, should benefit elderly patients with LSS and poor general condition due to multiple comorbidities. Finally, we introduce the concept of percutaneous transforaminal ventral facetectomy using a spinal percutaneous endoscope. J. Med. Invest. 64: 1-6, February, 2017.

Percutaneous full endoscopic lumbar foraminoplasty for adjacent level foraminal stenosis following vertebral intersegmental fusion in an awake and aware patient under local anesthesia: A case report

Percutaneous endoscopic surgery for the lumbar spine has become established in the last decade. It requires only an 8 mm skin incision, causes minimal damage to the paravertebral muscles, and can be performed under local anesthesia. With the advent of improved equipment, in particular the high-speed surgical drill, the indications for percutaneous endoscopic surgery have expanded to include lumbar spinal canal stenosis. Transforaminal percutaneous endoscopic discectomy has been used to treat intervertebral stenosis. However, it has been reported that adjacent level disc degeneration and foraminal stenosis can occur following intervertebral segmental fusion. When this adjacent level pathology becomes symptomatic, additional fusion surgery is often needed. We performed minimally invasive percutaneous full endoscopic lumbar foraminoplasty in an awake and aware 50-year-old woman under local anesthesia. The procedure was successful with no complications. Her radiculopathy, including muscle weakness and leg pain due to impingement of the exiting nerve, improved after the surgery. J. Med. Invest. 64: 291-295, August, 2017.

Failure rates of Asian-type anatomic medullary locking stemmed metal-on-metal total hip replacement: A cause for adverse tissue reactions to metal debris (ARMD)

BACKGROUND Adverse tissue reaction to metal debris (ARMD) as a secondary complication of Metal-on-metal total hip replacement (MoM THR) has been of concern. We have been performing cementless MoM THR using an Asian-type anatomic medullary locking (AML) stem. The purpose of this study is to examine the incident rate of ARMD, and the implant survival rate. METHODS The study included 187 patients (211 hip joints) who underwent MoM THR between February 2007 and November 2009 at our hospital and who were followed up for a minimum of 6 years. The cases included 174 female joints and 37 male joints. The average age at the time of surgery was 68.4 years. The average postoperative follow-up period was 87.5 months. RESULTS ARMD was observed in 23 joints postoperatively, and the incidence rate was 10.9%. Most of the instances occurred within the first 30 months postoperatively. Revision surgery was performed for 14 joints after conservative treatment failed, and we changed the bearing surface. During the intraoperative observation, black-colored deposition of metal debris on the head-neck junction was observed in 13 cases. Kaplan-Meier analysis using the replacement surgery as the end point showed that this implant has a survival rate of 93.8% 7 years after the primary surgery. CONCLUSIONS We conclude that the major cause of failure of Asian-type AML stemmed MoM THR is likely the breakage of the fixation between the taper neck and metal head at the head-neck junction.

Successful Endoscopic Surgery for L5 Radiculopathy Caused by Far-Lateral Disc Herniation at L5-S1 and L5 Isthmic Grade 2 Spondylolisthesis in a Professional Baseball Player

ABSTRACT Background: We report the case of a professional baseball player who had severe leg pain due to lumbar lateral disc herniation at L4-5 and isthmic spondylolisthesis at L5 (double crash syndrome). For early recovery to competitive level, we performed minimally invasive endoscopic decompression surgery without fusion. There are few reports to discuss the usefulness of minimally invasive treatment for top athletes. Methods: A 29-year-old professional baseball player who played catcher was referred to us with a complaint of right leg pain. The previous doctor diagnosed far-lateral disc herniation and Grade 2 isthmic spondylolisthesis and recommended arthrodesis at L5-S1 as treatment for both pathologies. Radiological imaging showed that the right L5 nerve root was impinged by the 2 lumbar disorders, namely, far-lateral disc herniation and a ragged edge around a pars defect. We had taken into account the patients occupation and his wish to avoid a lengthy sick leave, and we had performed endoscopic decompression surgery during the offseason. The far-lateral disc herniation at L5-S1 was removed under local anesthesia by percutaneous endoscopic discectomy, after which the ragged edge at the pars defect was removed under general anesthesia using a microendoscopic discectomy system. Given that the patient did not have any low back pain, arthrodesis was not considered. Results: The leg pain resolved after surgery. The following year (2015), the patient resumed playing baseball from the beginning of the season and played in 41 games. In the 2016 season, he played in 71 games without any symptoms. No further slippage was observed at radiological follow up 1 year after the surgery. Conclusions: Minimally invasive endoscopic surgery is an option for radiculopathy in very active patients who need an early return to their previous level of physical activity.