Takayuki Imura

Spinal canal enlargement procedure by restorative laminoplasty for the treatment of lumbar canal stenosis

BACKGROUND CONTEXT Multilevel fenestration or laminectomy is generally performed to treat the patient with lumbar canal stenosis (LCS). However, in patients requiring laminectomy, little attention has been paid to the later development of lumbar pain possibly caused by a removal of the posterior elements of the spine. In general, spinal instrumentation and fusion has been generally performed when laminectomy might cause severe postoperative spinal instability. Surgical methods where osteotomized vertebral arches are repositioned rather than removed have long been performed. However, they have never become widespread, possibly because of the complicated surgical procedures and poor postoperative arch stability, which leads to a long period of postoperative immobilization. PURPOSE The purpose of the present report was to introduce our surgical procedures of spinal canal enlargement using restorative laminoplasty and to report the results. STUDY DESIGN/SETTING This retrospective study was conducted to analyze the clinical results in 33 patients with lumbar canal stenosis who had been treated by our surgical procedures of spinal canal enlargement using restorative laminoplasty. PATIENT SAMPLE Subjects were 33 patients followed for at least 2 years after surgery. Meyerding Grade I degenerative spondylolisthesis was found in 10 patients, and degenerative scoliosis of more than 5 degrees was seen in 20 patients. Nine patients demonstrated both degenerative spondylolisthesis and degenerative scoliosis. OUTCOME MEASURES Using the Japanese Orthopedic Association (JOA) scoring system, lumbago, sciatica, leg numbness, muscle strength and gait were quantified before surgery, 1 year after surgery and at final examination (at least 2 years after surgery) to calculate improvement rates. Furthermore, correlations to age, gender, disease duration, degenerative spondylolisthesis and degenerative scoliosis were statistically analyzed. METHODS Our surgical procedures of spinal canal enlargement using restorative laminoplasty were performed for all patients. In our procedures, posterior elements were reapplied with an absorbable fixation (poli-L-lactic acid pins). No other fusion procedure was performed jointly. RESULTS The mean number of restored vertebral arches was 2.2, and mean surgery time was 131 minutes. Mean volume bleeding during surgery was 328.0 ml. In all patients, successful bone healing was obtained at a mean of 5 months after surgery. Mean improvement rate for the total JOA score was 80.6%. Mean improvement rates for lumbago and sciatica were 70.0% and 87.7%, respectively. Mean improvement rate for leg numbness was 50.8%. Mean improvement rates for leg muscle strength and intermittent claudication were 70.0% and 98.9%, respectively. No significant correlation was found between gender and overall improvement rate, between age and overall improvement rate, between age and leg numbness or between number of restored vertebral arches and overall improvement rate. The tendency was that the longer the disease duration, the lower the overall improvement rate, and the more severe the residual numbness. No significant correlation was found between disease duration and muscle strength or lumbago.A significant correlation was not found between the presence of preoperative Grade I degenerative spondylolisthesis and overall improvement rate or lumbago. However, a significant difference in severity of lumbago existed between patients with degenerative scoliosis of 9 degrees and below and those with degenerative scoliosis of 10 degrees and above. CONCLUSIONS Our surgical procedures of spinal canal enlargement using restorative laminoplasty produce complete decompression and anatomical reconstruction of the posterior elements, ligaments and muscles. Improvement in complaints of lumbago may be a consequence of the anatomical reconstruction of the posterior spinal elements. Overall, favorable results were obtained. The best results were obtained if surgery is performed within 2 years of the onset of LCS.

Surgical management of severe scoliosis with high risk pulmonary dysfunction in Duchenne muscular dystrophy: patient function, quality of life and satisfaction

In a previous study, the authors reported the clinical and radiological results of Duchenne muscular dystrophy (DMD) scoliosis surgery in 14 patients with a low FVC of <30%. The purpose of this study was to determine if surgery improved function and QOL in these patients. Furthermore, the authors assessed the patients’ and parents’ satisfaction. %FVC increased in all patients after preoperative inspiratory muscle training. Scoliosis surgery in this group of patients presented no increased risk of major complications. All-screw constructions and fusion offered the ability to correct spinal deformity in the coronal and pelvic obliquity initially, intermediate and long-term. All patients were encouraged to continue inspiratory muscle training after surgery. The mean rate of %FVC decline after surgery was 3.6% per year. Most patients and parents believed scoliosis surgery improved their function, sitting balance and quality of life even though patients were at high risk for major complications. Their satisfaction was also high.

Posterior corrective fusion using a double-trajectory technique (cortical bone trajectory combined with traditional trajectory) for degenerative lumbar scoliosis with osteoporosis: technical note.

The authors report on the usefulness and problems of a new surgical procedure--posterior corrective fusion using a double-trajectory technique (cortical bone trajectory technique combined with traditional trajectory technique) in a patient with degenerative lumbar scoliosis and osteoporosis--with the aim of achieving and maintaining complete correction. A 64-year-old woman with severe osteoporosis required decompression and posterior lumbar fusion. Teriparatide therapy had recently been initiated, but the impairment that she was experiencing in her activities of daily living was severe enough that surgery could not be delayed until teriparatide might show efficacy. We decided to employ the double-trajectory technique described in this report in order to achieve the most solid fixation. As of the 14-month follow-up evaluation, the patients postoperative course had been uneventful and there had been no loss of correction. The authors suggest that the double-trajectory method is useful for posterior fusion in patients with severe osteoporosis.

Teriparatide increases the insertional torque of pedicle screws during fusion surgery in patients with postmenopausal osteoporosis

OBJECT The object of this study was to examine the efficacy of preoperative teriparatide treatment for increasing the insertional torque of pedicle screws during fusion surgery in postmenopausal women with osteoporosis. METHODS Fusion surgery for the thoracic and/or lumbar spine was performed in 29 postmenopausal women with osteoporosis aged 65-82 years (mean 72.2 years). The patients were divided into 2 groups based on whether they were treated with teriparatide (n = 13) or not (n = 16) before the surgery. In the teriparatide-treated group, patients received preoperative teriparatide therapy as either a daily (20 μg/day, n = 7) or a weekly (56.5 μg/week, n = 6) injection for a mean of 61.4 days and a minimum of 31 days. During surgery, the insertional torque was measured in 212 screws inserted from T-7 to L-5 and compared between the 2 groups. The correlation between the insertional torque and the duration of preoperative teriparatide treatment was also investigated. RESULTS The mean insertional torque value in the teriparatide group was 1.28 ± 0.42 Nm, which was significantly higher than in the control group (1.08 ± 0.52 Nm, p < 0.01). There was no significant difference between the daily and the weekly teriparatide groups with respect to mean insertional torque value (1.34 ± 0.50 Nm and 1.18 ± 0.43 Nm, respectively, p = 0.07). There was negligible correlation between insertional torque and duration of preoperative teriparatide treatment (r(2) = 0.05, p < 0.01). CONCLUSIONS Teriparatide injections beginning at least 1 month prior to surgery were effective in increasing the insertional torque of pedicle screws during surgery in patients with postmenopausal osteoporosis. Preoperative teriparatide treatment might be an option for maximizing the purchase of the pedicle screws to the bone at the time of fusion surgery.

Triclosan-coated sutures reduce wound infections after spinal surgery: a retrospective, nonrandomized, clinical study.

BACKGROUND CONTEXT Surgical site infection (SSI) is a serious postoperative complication. The incidence of SSIs is lower in clean orthopedic surgery than in other fields, but it is higher after spinal surgery, reaching 4.15% in high-risk patients. Several studies reported that triclosan-coated polyglactin 910 sutures (Vicryl Plus; Ethicon, Inc., Somerville, NJ, USA) significantly reduced the infection rate in the general surgical, neurosurgical, and thoracic surgical fields. However, there have been no studies on the effects of such coated sutures on the incidence of SSIs in orthopedics. PURPOSE To compare the incidence of wound infections after spinal surgery using triclosan-coated suture materials with that of noncoated ones. STUDY DESIGN/SETTING A retrospective, nonrandomized, and clinical study. PATIENT SAMPLE From May 2010 to April 2012, 405 patients underwent a spinal surgical procedure in the Department of Orthopedic Surgery of two university hospitals. OUTCOME MEASURES The primary outcome was the number of wound infections and dehiscences. METHODS Two hundred five patients had a conventional wound closure with polyglactin 910 suture (Vicryl) between May 2010 and April 2011 (Time Period 1 [TP1]), and 200 patients underwent wound closure with triclosan-coated polyglactin 910 suture (Vicryl Plus) between May 2011 and April 2012 (TP2). Statistical comparisons of wound infections, dehiscence, and risk factors for poor wound healing or infection were performed. None of the authors has any conflict of interest associated with this study. RESULTS There were two cases of wound dehiscence in TP1 and one in TP2 (p=.509). Using noncoated sutures in TP1, eight patients (3.90%) had wound infections, whereas one patient (0.50%) had wound infections in TP2 (using triclosan-coated sutures); the difference was significant (p=.020). CONCLUSIONS The use of triclosan-coated polyglactin 910 sutures instead of polyglactin 910 sutures may reduce the number of wound infections after spinal surgery.

Surgical correction of spinal deformity in patients with congenital muscular dystrophy

BackgroundCongenital muscular dystrophy (CMD), among the myopathic disorders is one form of flaccid neuromuscular disorder (NMD). Patients with NMD frequently develop progressive spinal deformity. For NMD patients who have a severe spinal deformity, sitting is often difficult and is accompanied by pain and breakdown of the skin. Spinal deformity surgery in these patients has been highly effective in stabilizing the spine, maintaining upright, comfortable sitting balance, and improving patients’ quality of life. However, many studies have reported significant rates of peri/postoperative complications in these patients. To our knowledge, there has been no study on the results of spinal deformity surgery in patients with CMD. The purpose of this study was to review the clinical and radiological results of spinal deformity surgery in this group of patients with CMD.MethodsBetween 2004 and 2007, a total of 10 CMD patients underwent scoliosis surgery. There were three patients with Fukuyama CMD, three with Ullrich CMD, and 4 with nonsyndromic CMD (merosin-negative). They were nonambulatory. All the patients had standard posterior spinal fusion and pedicle-screw-alone fixation from T3 or T4 to L5 for spinal deformity. Our inclusion criteria required that each patient (1) had considerable difficulty with sitting balance and pain or breakdown of the skin due to scoliosis; (2) was able to ventilate his or her lung autonomously; (3) was not ventilator-dependent; and (4) did not have cardiac failure. Sufficient informed consent was important, and the decision to perform surgery was made by the patient/family with sufficient preoperative informed consent. Patients were trained with inspiratory muscle training (IMT) using an inspiratory muscle trainer (Threshold IMT) for 6 weeks prior to surgery Cardiac function was assessed preoperatively. Pulmonary function tests were performed preoperatively and postoperatively. Radiographic assessments were performed on sitting anteroposterior (AP) and lateral radiographs. These assessments were made periodically. The Cobb angles of the curves and spinal pelvic obliquity (SPO) on the coronal plane, thoracic kyphosis, and lumbar lordosis were measured. The preoperative AP radiograph and side-bending films were examined to determine flexibility. Patients’ and parents’ satisfaction were surveyed by a self-completed questionnaire at the last follow-up.ResultsPercent forced vital capacity (%FVC) increased from a mean of 30% before IMT to a mean of 34% the day before surgery. The preoperative scoliosis was 75° (range 61°–95°). The scoliotic curvature on preoperative side-bending films was 19° (range 11°–28°). All patients were extubated on the day of surgery. No patients developed cardiac or respiratory complications. The scoliotic curvature was 18° (range 10°–25°) immediately after surgery, and 19° (range 12°–27°) at the last follow-up. The pelvic obliquity improved from a mean of 17° (range 14°–20°) preoperatively to a mean of 6° (range 4°–9°) postoperatively and to 7° (range 4°–10°) at the last follow-up. Balanced sitting posture was achieved and maintained. On the sagittal plane, good reconstruction of sagittal plane alignment was recreated and maintained. There were no major complications or deaths. All patients/parents completed the outcome satisfaction questionnaire. Eight patients/parents were very satisfied and two were satisfied.ConclusionsPedicle-screw-alone fixation and fusion to L5 was safe and effective in CMD patients with scoliosis of <95° and pelvic obliquity of <20°. Scoliosis curves were flexible (75% correction) on side-bending films preoperatively. Curve correction and maintenance of correction in the coronal and sagittal plane was excellent. The pelvic obliquity significantly improved. Balanced sitting posture was achieved and maintained in all patients. Our patients with CMD spinal deformity and a moderately and severely decreased FVC could be operated on safely and successfully with general anesthesia. All patients were extubated in the operating room. There were no major complications or deaths. We believe a FVC of <30% alone is not a predisposition to pulmonary complications. However, cardiomyopathy might be a determining risk of mortality, and we believe surgery for these patients should be avoided. Patients’ and parents’ satisfaction was high.

Should we use cortical bone screws for cortical bone trajectory

OBJECT In 2009, Santoni et al. reported cortical bone trajectory (CBT) as a method of inserting pedicle screws to obtain more solid fixation, and proposed the use of cortical trajectory screws with a more closely placed thread (cortical screws) for CBT. Since the entry trajectory in CBT differs from that in the traditional trajectory, it is unclear whether the increased strength derives from the specific trajectory or the shape of the screw thread in contact with the cortical bone. Whether the use of cortical screws is always required with CBT thus remains unclear. The authors therefore investigated the relationship between screw entry trajectory and screw thread characteristics and pullout strength in animal experiments. METHODS Lumbar vertebrae (L1-L4) from 4-month-old female pigs were randomly assigned to one of 4 groups, with cancellous screws or cortical screws inserted via the traditional trajectory or CBT. For pullout strength testing, the screw was pulled out vertically against the direction of insertion. Rod pullout testing (toggle testing) was also performed, and the peak breaking strength was measured. RESULTS The maximum pullout strength was significantly greater for CBT using cortical screws than for the traditional trajectory using cancellous screws. Pullout strength tended to be higher when cortical screws were used in both CBT and the traditional trajectory, although the difference was not significant. Toggle testing showed no significant differences among the 4 groups. CONCLUSIONS The specific unconventional trajectory seemed to have a major impact on the increased strength obtained with CBT.

Can the caudal extent of fusion in the surgical treatment of scoliosis in Duchenne muscular dystrophy be stopped at lumbar 5

Instrumentation and fusion to the sacrum/pelvis has been a mainstay in the surgical treatment of scoliosis in Duchenne muscular dystrophy (DMD) and is recommended to correct pelvic obliquity. The caudal extent of instrumentation and fusion in the surgical treatment of scoliosis in DMD has remained a matter of considerable debate, and there have been few studies on the use of segmental pedicle screw instrumentation for this pathology. From 2004 to 2007, a total of 28 patients with DMD underwent segmental pedicle screw instrumentation and fusion only to L5. Assessment was performed clinically and with radiologic measurements. All patients had a curve with the apex at L2 or higher preoperatively. Preoperative coronal curve averaged 74°, with a postoperative mean of 14°, and 17° at the last follow-up. The pelvic obliquity improved from 17° preoperatively to 6° postoperatively, and 6° at the last follow-up. Good sagittal plane alignment was recreated after surgery and maintained long term. In 23 patients with a preoperative L5 tilt of less than 15°, the pelvic obliquity was effectively corrected to less than 10° and maintained by adequately addressing spinal deformity, while five patients with a preoperative L5 tilt of more than 15° had a postoperative pelvic obliquity of more than 15°. Segmental pedicle screw instrumentation and fusion to L5 was effective and safe in patients with DMD scoliosis with a minimal L5 tilt (<15°) and a curve with the apex at L2 or higher, both initially and long term, obviating the need for fixation to the sacrum/pelvis. Segmental pedicle screw instrumentation and fusion to L5 was safe and effective in patients with DMD scoliosis with stable L5/S1 articulation as evidenced by a minimal L5 tilt of less than 15°, even though pelvic obliquity was significant. There was no major complication. With rigid segmental pedicle screw instrumentation, the caudal extent of fusion in the treatment of DMD scoliosis should be determined by the degree of L5 tilt. This method in appropriate patients can be a viable alternative to instrumentation and fusion to the sacrum/pelvis in the surgical treatment of DMD scoliosis.

Two-year results for scoliosis secondary to Duchenne muscular dystrophy fused to lumbar 5 with segmental pedicle screw instrumentation

BackgroundInstrumentation and fusion to the sacrum/pelvis has been a mainstay in the surgical treatment of scoliosis in patients with Duchenne muscular dystrophy since the development of the intrailiac post. It is recommended for correcting pelvic obliquity. However, caudal extent of instrumentation and fusion has remained a matter of considerable debate. This study was performed to determine the efficacy and safety of stopping segmental pedicle screw constructs at L5 during surgical treatment of scoliosis associated with Duchenne muscular dystrophy (DMD).MethodsFrom May 2005 to June 2007, a total of 20 consecutive patients underwent posterior spinal fusion and segmental pedicle screw instrumentation only to L5 for scoliosis secondary to DMD. All patients had progressive scoliosis, difficulty sitting, and back pain before surgery. A minimum 2-year follow-up was required for inclusion in this study. Assessment was performed clinically and with radiological measurements. The Cobb angles of the curves and spinal pelvic obliquity were measured on the coronal plane. Thoracic kyphosis and lumbar lordosis were measured on the sagittal plane. These radiographic assessments were performed before surgery, immediately after surgery, and at a 3-month interval thereafter. The operating time, blood loss, and complications were evaluated. Patients were questioned about whether they had difficulty sitting and felt back pain before surgery and at 6 weeks, 1 year, and 2 years after surgery.ResultsA total of 20 patients, aged 11–17 years, were enrolled. The average follow-up period was 37 months. Preoperative coronal curves averaged 70° (range 51°–85°), with a postoperative mean of 15° (range 8°–25°) and a mean of 17° (range 9°–27°) at the last follow-up. Pelvic obliquity improved from 13° (range 7°–15°) preoperatively to 5° degrees (range 3°–8°) postoperatively and 6° (range 3°–9°) at the last follow-up. Good sagittal plane alignment was recreated and maintained. Only a small loss of correction of scoliosis and pelvic obliquity was noted. The mean operating time was 271 min (range 232–308 min). The mean intraoperative blood loss was 890 ml (range 660–1260 ml). The mean total blood loss was 2100 ml (range 1250–2880 ml). There was no major complication. All patients reported that difficulty sitting and back pain were alleviated after surgery.ConclusionSegmental pedicle screw instrumentation and fusion only to L5 is safe and effective in patients with DMD scoliosis of <85° and pelvic obliquity of <15°. Good sagittal plane alignment was achieved and maintained. All patients benefited from surgery in terms of improved quality of life. There was no major complication.

Remarkable regression of a giant cell tumor of the cervical spine treated conservatively with denosumab: A case report

Highlights • Denosumab induced remarkable regression and surrounding sclerosis of the giant cell tumor at 5th cervical vertebral body six months after the administration and these findings are sustained for two years.• FDG-PET/CT showed significant uptake of the tracer before administration of denosumab but no obvious uptake was noted two years after the administration.• The patient has been asymptomatic for two years since denosumab treatment started without any evidence of the recurrence of the giant cell tumor.