Zinc improves Denosumab and eldecalcitol efficacy for bone mineral density in patients with hypozincemia

INTRODUCTION

We aimed to investigate the effects of zinc deficiency and zinc medication in osteoporosis patients undergoing denosumab (DMAb).

MATERIALS AND METHODS

This retrospective study was conducted at a single hospital. The participants were female osteoporosis patients visiting between April 2019 and April 2020. All patients were treated with DMAb and eldecalcitol and recommended zinc-rich food. Based on zinc medication and serum zinc levels at the 12th month of dietary guidance, patients were categorized into the following four groups: hypozincemia with zinc medication, latent zinc deficiency with zinc medication, without zinc medication, and control without zinc medication. Longitudinal serum zinc concentrations, bone mineral density (BMD), and occurrence of fractures were measured. We investigated the factors influencing no response to DMAb and eldecalcitol treatment.

RESULTS

Among the 145 patients followed up for 24 months, dietary guidance did not change the serum zinc concentration; however, zinc medication significantly increased these levels. The hypozincemia group did not show a significant BMD increase in the lumbar spine and femoral neck after DMAb and eldecalcitol treatment during dietary guidance; however, zinc medication increased these to the same levels as the other groups. In multivariate analyses, hypozincemia and thyroid disease were identified as the factors affecting no response. While 28.2% of patients with latent zinc deficiency without zinc medication suffered fractures, no fractures occurred in hypozincemia patients with zinc medication.

CONCLUSION

Hypozincemia may reduce the efficacy of DMAb and eldecalcitol in increasing BMD and fracture prevention.

Potential of whole-body dual-energy X-ray absorptiometry to predict muscle size of psoas major, gluteus maximus and back muscles

BACKGROUND

Measurement of trunk muscle cross-sectional area (CSA) using axial magnetic resonance imaging (MRI) is considered clinically meaningful for understanding several spinal pathologies, such as low back pain and spinal sagittal imbalance. However, it remains unclear whether trunk muscle mass (TMM) measured using dual-energy X-ray absorptiometry (DXA) can predict the trunk muscle CSA. The aim of this study is to determine if DXA-derived TMM is associated and predicts with CSA of paraspinal muscles and gluteus maximus measured using MRI in healthy volunteers.

METHODS

A total of 48 healthy volunteers underwent whole-body DXA and MRI of the spinopelvic region. The CSA of the psoas major, back muscles, and gluteus maximus were measured on axial MRI. Correlations and linear regressions between the TMM measured using DXA and the CSA of each musculature were investigated.

RESULTS

There was a weak correlation between TMM and CSA of the psoas major in men (r = 0.39, P = 0.0678), and the linear regression was y = 301.74x - 401.24 (R2 = 0.2976, P = 0.0070). A moderate correlation was found in women (r = 0.58, P = 0.0021), and the linear regression was y = 230.21x - 695.29 (R2 = 0.4445, P = 0.0003). Moderate correlations were observed between TMM and CSA of the back muscles in both men (r = 0.63, P = 0.0012) and women (r = 0.63, P = 0.0007), the linear regression was y = 468.52x + 3688.5 (R2 = 0.5505, P < 0.0001) in men and y = 477.39x + 2364.1 (R2 = 0.564, P < 0.0001) in women. There was a strong correlation between TMM and CSA of the gluteus maximus in men (r = 0.72, P < 0.0001), and the linear regression was y = 252.69x - 880.5 (R2 = 0.6906, P < 0.0001). A moderate correlation was found in women (r = 0.69, P < 0.0001), and the linear regression was y = 230.74x - 231.32 (R2 = 0.6542, P < 0.0001).

CONCLUSIONS

The DXA-derived TMM was able to predict the CSA of the psoas major, back muscles, and gluteus maximus, and significantly correlated with the CSA of the back muscles and gluteus maximus. It might be a safer and cheaper alternative for evaluating the size of the back muscles and gluteus maximus.

Effect of pre-operative HbA1c and blood glucose level on the surgical site infection after lumbar instrumentation surgery

BACKGROUND

This study aims to investigate the effect of pre-operative hemoglobin A1c (HbA1c) and pre-operative blood glucose control on the rate of surgical site infection (SSI) after posterior lumbar instrumentation surgery in diabetes mellitus (DM) patients.

METHODS

A total of 1046 patients who had undergone posterior lumbar instrumentation surgery were reviewed. Based on pre-operative HbA1c, patients were divided into three groups: non-DM group, low HbA1c group (HbA1c < 7.0 % in DM) and high HbA1c group (≥7.0). As well, based on the status of blood glucose control in DM patients immediately before surgery, patients were divided into two groups: good control group (post-prandial blood glucose [PBG] < 200 mg/dl) and poor control group (≥200). The rate of SSI was compared among these groups.

RESULTS

SSI occurred in 1.9 % in non-DM group, 2.4 % in low HbA1c group, and 9.3 % in high HbA1c group. Compared with non-DM group, high HbA1c group had significantly higher rate of SSI (p = 0.001). There was not statistically different between non-DM and low HbA1c groups (p = 0.550). SSI occurred in 2.2 % in good control group, and 10.2 % in poor control group. The rate of SSI was significantly lower in good control group (p = 0.013).

CONCLUSION

This study showed that the rate of SSI after posterior lumbar instrumentation surgery tend to be higher in DM patients with high HbA1c. However, the rate might be reduced to the same level as that of non-DM group by lowering PBG to <200 mg/dl immediately before surgery.

Posterior lumbar fusion surgery doesn't change sexual activities in patients with lumbar degenerative disease: an observational study

BACKGROUND

There are few studies about sexual function in the patient with posterior lumbar spinal fusion for degenerative lumbar disease. The aim of this study is to investigate sexual activities in patients with lumbar degenerative disease before and after lumbar fusion surgery.

METHODS

We recruited 35 patients who underwent lumbar spinal fusion at the age of 55 years or younger. They were 17 men and 18 women with a mean age of 47.4 years. After informed consent, the patients were asked to complete anonymous questionnaire concerning sexual desire, activity, and satisfaction before and after surgery.

RESULTS

In the presick period, 69% of the patients had sexual desire, and 79% achieved satisfaction during sexual activity. Lumbar degenerative disease decreased sexual desire and frequency of sexual activity in 40%, and 74% respectively. Before surgery, satisfaction in sexual activities decreased in 53%, and 55% of the patients felt discomfort during sexual activity. Adjustment in sexual position was required in 44% of man and 54% of woman. After surgery, Sexual desire, frequency of sexual activity and satisfaction did not regain after surgery in 94%, 93% and 92%, respectively. Those who did not feel discomfort after surgery was significantly lower VAS in both low back pain and leg pain than the patients felt discomfort (low back pain; p = 0.024, leg pain; p = 0.046).

CONCLUSION

This study demonstrated that lumbar degenerative diseases decreased sexual desire, frequency of sexual activity and satisfaction, and little of the patients regained their sexual activities after posterior lumbar fusion surgery in the middle-aged patients.

Characteristics of older patients with postmenopausal osteoporosis who developed loss of muscle mass during the COVID-19 pandemic - a case-control study

BACKGROUND

Under the restriction of social activities during the coronavirus disease 2019 (COVID-19) pandemic, there was concern about the loss of muscle mass due to a decrease in physical activity for the elderly. The purpose of this study was to investigate the characteristics of older patients with postmenopausal osteoporosis who developed loss of muscle mass during the COVID-19 pandemic in Japan.

METHODS

A total of 54 patients with postmenopausal osteoporosis were evaluated in this study. Whole-body dual-energy X-ray absorptiometry was performed pre- and post-COVID-19 pandemic to measure trunk and lower limb muscle mass. At the time of the post-COVID-19 pandemic, we conducted a survey to compare lifestyle before pandemic (the frequency of going out, the frequency of meeting acquaintances or families living apart, regular exercise habits, walking time, family structure), and comorbidities between the muscle mass loss (ML) group and the muscle mass maintenance (MM) group. The ML group consisted of patients with at least a 5% decrease in lower limb muscle mass or trunk muscle mass.

RESULTS

A significant difference was found only for the family structure (P = 0.0279); in the ML group, those living alone were the largest group, while in the MM group they were the smallest group.

CONCLUSIONS

The ML group was significantly more likely to live alone than the MM group. The current study showed that loss of muscle mass was more common in patients living alone.

Clinical outcomes of short-segment lumbar fusion in patients older than 85 years with a minimum 2-year follow-up

OBJECTIVE

Although the number of elderly patients requiring lumbar fusion for lumbar degenerative disorders has increased over time, the postoperative outcomes of lumbar fusion in very elderly patients (> 85 years) remains unknown. This study aimed to evaluate the comprehensive outcomes of lumbar fusion in elderly patients older than 85 years with mid-term follow-up.

METHODS

The authors retrospectively researched patients older than 85 years who underwent single- or double-level posterior lumbar interbody fusion or transforaminal lumbar interbody fusion from 2012 to 2019. Twenty-nine patients who had at least 2 years of follow-up were included in this study. The average age was 86.4 years, and the average follow-up period was 42.2 months. Each patient was matched with 60- to 75-year-old controls. The Oswestry Disability Index (ODI) score; Roland-Morris Disability Questionnaire (RMDQ) score; Japanese Orthopaedic Association (JOA) score; JOA recovery rate; and low-back pain (LBP), leg pain, and leg numbness visual analog scale (VAS) scores were obtained. The spinopelvic parameters were measured using lateral standing radiographs of the whole spine.

RESULTS

Although there were no significant differences in the ODI, RMDQ, JOA recovery rate, and leg pain and leg numbness VAS scores at 2 years postoperatively between the very elderly and control groups, the VAS LBP score was significantly lower in the very elderly group than in the control group. Preoperative and postoperative sagittal vertical axes were significantly higher and sacral slopes were significantly lower in the very elderly group than in the control group. The incidences of postoperative delirium and new lumbar vertebral fracture were significantly higher in the very elderly group (17.2%) than in the control group (4.6%).

CONCLUSIONS

This study showed that lumbar fusion could be performed in patients older than 85 years with satisfactory postoperative outcomes at the 2-year follow-up. In contrast, progressive spinopelvic sagittal imbalance, the incidence of lumbar vertebral fracture up to the final follow-up, and postoperative delirium were greater in the very elderly group than in the control group.

Characteristics of the Patients with Poor Clinical Outcomes After Symptomatic Postoperative Lumbar Epidural Hematoma

OBJECTIVE

Symptomatic postoperative lumbar epidural hematoma (PLEH) may lead to poor outcomes even after evacuation. This study aimed to verify the short-term clinical outcomes after the evacuation of PLEH and to clarify the characteristics of the patients with poor postoperative outcomes.

METHODS

Twenty-five patients (average age; 70.4 years) underwent PLEH evacuation after lumbar spine surgery. The mean follow-up period was 12.0 (range 3-37) months. Pre and postoperative Japanese Orthopedic Association scores and visual analog scale (VAS) of low back pain (LBP), leg pain, and leg numbness were retrospectively collected. The dural sac cross-sectional area at the most compressed level was measured on magnetic resonance imaging. The patients were classified into 2 groups: poor outcome group (P group) had less than 50% of Japanese Orthopedic Associationrecovery rate and good group (G group) with 50% or more recovery rate.

RESULTS

The rate of delayed evacuation (over 24 hours of onset) was significantly higher in P group than in G group (P = 0.027). There was no significant difference in dural sac cross-sectional areabetween the 2 groups (P = 0.438). VAS of LBP, leg pain, and leg numbness in G group significantly improved postoperatively. Although VAS of LBP and leg pain in P group significantly improved postoperatively, there was no significant difference between the pre and postoperative VAS of leg numbness.

CONCLUSIONS

Delayed evacuation of PLEH can lead to poor postoperative outcomes after lumbar spine surgery. Moreover, patients with poor outcomes remained with postoperative leg numbness. Early evacuation of symptomatic PLEH is key to avoid poor outcomes and persistent leg numbness.

Perioperative Complications of Open Spine Surgery in Older Adults over 90 Years of Age

Introduction

Despite perioperative risks in nonagenarian patients who undergo open spine surgery for degeneration disorder or spinal trauma being of great interest, the prevalence of complications in this group remains unclear. This study aims to examine the perioperative complications of open spine surgery in the elderly over 90 years of age.

Methods

Preoperative and intraoperative characteristics including the American Society of Anesthesiologists Physical Status (ASA-PS) class, type of surgery, and complications within 30 postoperative days were retrospectively collected from the medical records of nonagenarians who underwent open spine surgery between April 2004 and July 2019 at our spine centers.

Results

A total of 48 patients met the inclusion criteria of this study. All belong to ASA-PS class 2 (69%) or 3. Preoperative American Spinal Injury Association Impairment Scale grades in trauma group were grade A in 4 cases, B in 1 case, C in 5 cases, D in 11 cases, and E in 1 case. Major complications (deep surgical site infection, cardiac event, respiratory disorder, gastrointestinal hemorrhage, and renal failure) occurred in 13 cases, and the rate of overall perioperative complications was 45.8%. One patient who underwent cervical stabilization for cervical fracture dislocation died at postoperative 13 days due to respiratory disorder. The rates of major complications and overall perioperative complications were 3.6% and 14.3% in the degenerative group and 45.5% and 81.8% in the trauma group, respectively. Especially in the trauma group, respiratory disorder occurred in 7 cases, delirium in 11 cases, and urinary tract infection in 5 cases.

Conclusions

Although the perioperative complication rate reached 81.8% in spinal trauma cases, the complication rate in degenerative disorders was relatively low as 14.3%. Open spine surgery for degenerative disorders can be relatively safe even in nonagenarians, whereas the risks of perioperative complications, including respiratory disorder and delirium, were high in spinal trauma cases.

Pre-existing adjacent level foraminal stenosis does not affect the outcome of a single level lumbar interbody fusion

BACKGROUND

The aim of this study was to investigate whether or not pre-existing asymptomatic neuroforaminal stenosis adjacent to the fusion level develops adjacent segment disease (ASD) after single-level lumbar interbody fusion.

SUMMARY AND BACKGROUND DATA

Risk factors of ASD after spinal fusion have been well investigated, but there have been few studies focused on the relationship between ASD and pre-existing asymptomatic neuroforaminal stenosis.

METHODS

A total of 302 patients who had undergone a single-level lumbar interbody fusion were reviewed at a minimum of 2 year follow-up. They were 109 men and 193 women with a mean age of 68.8 years. Follow-up periods was averaged 53.5 months. ASD was defined as neurological deterioration related to adjacent segment pathologies which required an additional surgery. Based on the pathologies, patients were divided into three categories: ASD due to foraminal stenosis (ASD-FS), ASD due to central stenosis (ASD-CS), and ASD due to herniated disc (ASD-HD). Measured variables were age, gender, diagnosis, BMI, decompression procedures at adjacent segments, preoperative anterior/posterior slip, asymptomatic neuroforaminal stenosis, facet tropism, and postoperative spinopelvic parameters.

RESULTS

Thirty-eight patients (12.6%) developed ASD. There were 15 patients with ASD-FS, 18 patients with ASD-CS, and five patients with ASD-HD. Lumbar lordosis (LL) and sacral slope (SS) were significantly smaller and pelvic tilt (PT) was significantly larger in ASD-FS. Asymptomatic neuroforaminal stenosis was detected preoperatively in 33.3% of the ASD-FS group, and 18.6% of non-ASD group; the incidence was not significantly different.

CONCLUSIONS

Adjacent-level neuroforaminal stenosis was not a significant risk of ASD after single-level lumbar interbody fusion, and might not need to be fused if asymptomatic.

Trends of Spine Surgeries during the First COVID-19 Semi-Lockdown: Survey in a Non-Epidemic Region in Japan

Introduction

Methods

Results

Conclusions

Clinical Outcomes and Postoperative Radiographic Assessment of Osteoplastic Hemilaminectomy in the Treatment of Lumbar Foraminal Nerve Root Compression

Introduction

Osteoplastic hemilaminectomy for the treatment of lumbar foraminal nerve root compression is a safe technique as the exiting nerve root can be directly observed during neuroforaminal decompression without spinal fusion. Moreover, this procedure allows anatomical reconstruction of the posterior elements. However, there might be a potential risk for the progression of lumbar segmental instability after performing this procedure. This study aimed to review the radiographic and clinical outcomes of osteoplastic hemilaminectomy for the treatment of lumbar foraminal nerve root compression.

Methods

We retrospectively reviewed 51 patients who underwent osteoplastic hemilaminectomy with a minimum follow-up of 2 years. The clinical outcomes were evaluated using the visual analog scale (VAS) for low back pain, leg pain, and numbness and the Japanese Orthopaedic Association (JOA) score. Lumbar segmental instability was evaluated as a radiographic assessment using functional radiography. The mean follow-up period was 65 months.

Results

The preoperative VASs for low back pain, leg pain, and numbness were 46±31, 72±26, and 43±34, respectively, which were improved to 24±23, 19±23, and 19±23, respectively. The JOA score was also improved from 14±5 to 22±4. Three patients (5.9%) were reoperated due to recurrent disc herniation within 2 years following surgery. In addition, three patients (5.9%) developed postoperative lumbar segmental instability but did not require additional surgery.

Conclusions

The current study revealed that 94.1% of the patients who underwent osteoplastic hemilaminectomy achieved a significant improvement in the clinical outcomes and did not require additional surgery within 2 years following the procedure. Over a 5-year follow-up on average, 5.9% of the subjects developed postoperative lumbar segmental instability; however, they have maintained acceptable clinical conditions.

Bone Metabolism in the Healing Process of Lumbar Interbody Fusion: Temporal Changes of Bone Turnover Markers

STUDY DESIGN

Prospective longitudinal study.

OBJECTIVE

The aim of this study was to evaluate temporal changes of bone turnover markers (BTMs) after lumbar spinal fusion in patients without osteoporosis.

SUMMARY OF BACKGROUND DATA

Radiological studies are the standard method to monitor bony fusion, but they do not allow a timely assessment of bone healing. BTMs react rapidly to changes in bone metabolism during fusion process and could be an additional tool to monitor this process.

METHODS

A total of 78 nonosteoporosis patients who had undergone one- or two-level transforaminal lumbar interbody fusion were included. Fusion status was assessed using computed tomography sagittal and coronal images. Serum levels of bone-specific alkaline phosphatase (BAP), procollagen type 1 amino-terminal propeptide (P1NP), and osteocalcin (OC) were measured to assess bone formation, and tartrate-resistant acid phosphatase 5b (TRACP-5b) was measured to assess bone resorption. Serum samples were obtained before surgery and at 1, 2, 4, 8, 13, 26, 39, and 52 weeks after surgery.

RESULTS

A solid fusion was achieved in 71 of 78 patients (91%), and seven patients resulted in pseudarthrosis. In the fusion group, the level of all BTMs once decreased at 1 postoperative week. Then, BAP and P1NP reached a peak at 4 weeks after surgery, and TRACP-5b and OC peaked at 8 weeks. Thereafter, the level of P1NP and TRACP-5b gradually got closer to the baseline over a year, and BAP kept high until 52 postoperative weeks. In the pseudarthrosis group, peak level of BTMs was significantly higher and the increased level of BAP and P1NP was kept until 52 weeks.

CONCLUSION

The present study demonstrated dynamics of BTMs after lumbar spinal fusion in patients without osteoporosis. These normal population data contribute as a baseline to evaluate the effect of osteogenic agents on bone metabolism after spinal fusion.Level of Evidence: 2.

Close association between non-alcoholic fatty liver disease and ossification of the posterior longitudinal ligament of the spine

Ossification of the posterior longitudinal ligament (OPLL) of the spine is a disease of unknown etiology occurring frequently in individuals with metabolic disturbances. Obesity has been suggested as a potential risk factor for the severity of OPLL. We aimed to investigate whether non-alcoholic fatty liver disease (NAFLD) is associated with OPLL severity. We assessed the severity of NAFLD by a liver-to-spleen (L/S) ratio on computed tomography (CT) scans of 85 symptomatic OPLL patients at a single institution in Japan. We also assessed the severity of OPLL by CT reconstruction sagittal and axial images. The prevalence of NAFLD in middle-aged patients (age < 70 years, n = 50) was 80.3%, which was 2.5-8 times higher than that in the general Japanese population (9-30%). The ossification index of the spinal ligaments increased in proportion to the severity of fatty liver. The L/S ratio was revealed as a significant risk factor associated with the total ossification index (standardized β: -0.40, 95% confidence interval - 54.34 to - 4.22). This study suggests the potential contribution of NAFLD to the progression of OPLL. The close association between NAFLD and OPLL demonstrated in this study warrants further study to elucidate the causal nature of this relationship.

Impact of spino-pelvic and global spinal alignment on the risk of osteoporotic vertebral collapse

Introduction

Numerous studies have reported the risk factors of osteoporotic vertebral collapse. However, whether spino-pelvic and global spinal alignments are associated with the occurrence of osteoporotic vertebral collapse remains unclear. This study aimed to investigate the association between spino-pelvic and global spinal alignments and the occurrence of osteoporotic vertebral collapse.

Methods

A total of 46 consecutive patients who underwent a nonoperative treatment for a single-level fresh osteoporotic thoracolumbar vertebral compression fracture (T10 to L3) were retrospectively reviewed. The parameters evaluated were the pelvic incidence, anterior deviation of the C7 plumb line, distance between the C7 plumb line and the center of the fractured vertebra, and kyphotic wedge angle of the fractured vertebra in a standing whole-spine radiograph at the beginning of the nonoperative treatment. As an outcome measure, the presence or absence of osteoporotic vertebral collapse was radiographically evaluated at the final follow-up. Multiple logistic regression analysis was used to determine significant risk factors of osteoporotic vertebral collapse.

Results

The mean values for each parameter were as follows: pelvic incidence, 58.0 degrees; anterior deviation of the C7 plumb line, 3.0 cm; distance between the C7 plumb line and the center of the fractured vertebra, 5.7 cm; and kyphotic wedge angle of the fractured vertebra, 14.6 degrees. Multiple logistic regression analysis revealed that the distance between the C7 plumb line and center of the fractured vertebra was a significant risk factor of osteoporotic vertebral collapse (p = 0.012; odds ratio, 1.025). The anterior deviation of the C7 plumb line (p = 0.214), pelvic incidence (p = 0.728), and kyphotic wedge angle of the fractured vertebra (p = 0.07) did not affect the occurrence of osteoporotic vertebral collapse.

Conclusions

A large distance between the C7 plumb line and center of the fractured vertebra was a significant risk factor of osteoporotic vertebral collapse. The distance approximately represents that of between gravity center of trunk cranial to the fractured vertebra and the fractured vertebra. Accordingly, the large distance may cause larger flexion moment to the fractured site, leading to stress concentration that results in insufficient bone healing.

Effect of teriparatide (rh-PTH 1-34) versus bisphosphonate on the healing of osteoporotic vertebral compression fracture: A retrospective comparative study

Background

Teriparatide (recombinant human parathyroid hormone 1–34) is increasingly used for the treatment of severe osteoporosis because it stimulates bone formation and may potentially enhance fracture healing. The objective of this study was to investigate the effects of teriparatide versus a bisphosphonate on radiographic outcomes in the treatment of osteoporotic vertebral compression fractures (OVCF).

Methods

A total of 98 patients undergoing non-operative treatment for recent single-level OVCF were reviewed retrospectively. Thirty-eight patients were treated by a once-daily subcutaneous injection of 20 micrograms of teriparatide (TPD group), whereas 60 patients received 35 mg of alendronate weekly (BP group). Except for these medications, the same treatment protocol was applied to both groups. The radiographic assessments included union status, vertebral kyphosis, and mid-vertebral body height. The rates of fracture site surgical intervention were also compared between the two groups. The mean follow-up period was 27 months (median 22.5, range 2 – 75 months).

Results

Cox regression analysis showed that TPD reduced the time-to-union (adjusted relative hazard ratio: 1.86, 95% C.I.: 1.21 – 2.83). The union rate at six months after treatment was 89% in the TPD group and 68% in the BP group; the surgical intervention rate was significantly higher in the TPD group (p = 0.026, adjusted odds ratio: 8.15, 95% C.I.: 2.02 – 43.33). The change in local kyphosis was 4.6° in the TPD group and 3.8° in the BP group (p = 0.495, paired t-test). The change of mid-vertebral body height was 4.4 mm in the TPD group and 3.4 mm in the BP group (p = 0.228, paired t-test). Fracture site surgical interventions were not required in the TPD group; however, two patients in the BP group eventually underwent surgical treatment for symptomatic non-union or vertebral collapse.

Conclusions

This retrospective study suggests that teriparatide may enhance fracture healing and improve the union rate in OVCF.

Does balloon kyphoplasty improve the global spinal alignment in osteoporotic vertebral fracture?

PURPOSE

Balloon kyphoplasty (BKP) has been a well-accepted procedure in the treatment of osteoporotic vertebral compression fracture (OVCF), whereas it remains unclear whether or not this procedure has an impact on the global spinal alignment. The purpose of this study is to evaluate the effect of BKP on the global spinal alignment in OVCF.

METHODS

Fifty-six consecutive patients who had undergone BKP for symptomatic OVCF were retrospectively reviewed with a mean follow-up of 32 months. They were seven males and 49 females with a mean age of 75 years. Radiographic assessment was performed using upright whole spine radiographs. The parameters included vertebral kyphosis, mid-vertebral body height and global sagittal spinal alignment (C7 plumb line deviation). Clinical outcomes were evaluated using visual analog scale of back pain.

RESULTS

Fifty-one of 56 patients (91.1 %) achieved immediate pain relief. Vertebral kyphosis significantly decreased from 18 to 14 degrees, but 43 patients (76.8 %) still had more than 10 degrees of local kyphosis. Subsequent vertebral compression fractures were observed in seven patients (12.5 %). Anterior deviation of a C7 plumb line (C7PL) was 3.1 cm pre-operatively, 3.1 cm postoperatively, and significantly increased to 5.9 cm at the final follow-up. Consistent results were obtained in those with pre-operative sagittal imbalance (>5 cm anterior deviation of C7PL) and with pre-existing OVCFs.

CONCLUSIONS

BKP contributed to immediate pain relief, but did not improve the global sagittal spinal alignment after OVCF. This procedure should be solely indicated for painful OVCF or non-union, and could not be expected to restore the global sagittal alignment.

Is closed-suction drainage necessary for single-level lumbar decompression?: review of 560 cases

BACKGROUND

Closed-suction drainage is commonly used for prevention of postoperative hematoma and associated neurologic compromise after lumbar decompression, but it remains unclear whether suction drainage reduces postoperative complications.

QUESTIONS/PURPOSES

We evaluated the efficacy of closed-suction drainage in single-level lumbar decompression surgery.

PATIENTS AND METHODS

We retrospectively reviewed 560 patients who underwent single-level lumbar decompression or discectomy. We routinely used closed-suction drainage in all spinal surgeries until July 2003, and thereafter, we did not use drains in single-level lumbar decompression surgery. These two groups (298 patients in the group that received drains, 262 in the group that did not receive drains) were compared for rates of wound infection and epidural hematoma.

RESULTS

Mean operating time (55 versus 56 minutes) and intraoperative blood loss (64 versus 57 mL) were not different between the two groups. None of 560 patients had a wound infection requiring surgical intervention. The rate of postoperative hematoma was 0.7% in the group that received drains (two of 298 patients) and 0% in the group that did not receive drains (zero of 262 patients).

CONCLUSIONS

In this study, the risk of wound infection and hematomas in single-level lumbar decompression surgery was not influenced by use of a drain. The use of postoperative wound drainage in patients with potential risk for epidural bleeding in situations such as multiple-level decompression, instrumentation surgery, anticoagulant therapy, trauma, and tumors or metastases needs additional study.

LEVEL OF EVIDENCE

Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

A minimum 10-year follow-up of posterior dynamic stabilization using Graf artificial ligament

STUDY DESIGN

A retrospective long-term follow-up study.

OBJECTIVES

To report minimum 10-year follow-up results of posterior dynamic stabilization using Graf artificial ligament and to evaluate the role and limitations of this procedure in the treatment of degenerative lumbar disorders.

SUMMARY OF BACKGROUND

Motion-preserving surgeries, including artificial disc replacement and ligamentoplasty, are increasingly gaining interest to avoid adverse effects of spinal fusion, but literature addressing long-term results is sparse.

METHODS

A total of 56 consecutive patients who underwent Graf ligamentoplasty were reviewed at a minimum 10-year follow-up. Forty-three patients in the original cohort had sufficient clinical and radiographic follow-up for analysis. The pathologies included degenerative spondylolisthesis in 23 patients, disc herniation with flexion instability in 13 patients, spinal stenosis with flexion instability in 4 patients, and degenerative scoliosis in 3 patients. Single-level procedures were performed in 36 patients; multilevel procedures were performed in 7 patients. Radiographic and clinical assessments were performed before surgery and at the final follow-up.

RESULTS

Disability due to low back pain and/or sciatic symptoms was significantly improved in the patients with degenerative spondylolisthesis or flexion instability. However, degenerative scoliosis and/or laterolisthesis were associated with poor clinical improvement. In radiographic assessment, segmental lordosis was maintained in 10.9 degrees, and flexion-extension motion was averaged 3.6 degrees at the final follow-up. Facet arthrodesis eventually occurred in 14 patients (32.6%) at an average of 82 months after surgery. Additional surgeries were required in 3 patients (7.0%) for adjacent segment pathologies.

CONCLUSION

The long-term results showed that Graf ligamentoplasty is an effective treatment option for low-grade degenerative spondylolisthesis and flexion instability. However, this procedure has limitations to correct spinal deformity, and is not advocated for the treatment of degenerative scoliosis and laterolisthesis.

Effective prevention of surgical site infection using a Centers for Disease Control and Prevention guideline-based antimicrobial prophylaxis in lumbar spine surgery

OBJECT

Antimicrobial prophylaxis (AMP) reduces the rate of surgical site infection (SSI) in lumbar spine surgery, but a great deal of variation exists regarding the timing and duration of AMP. The authors had previously used prophylactic antibiotics for 5 to 7 postoperative days. Based on the Centers for Disease Control and Prevention (CDC) guideline, the AMP period was changed to the day of surgery only. In the current study, the authors compared the rate of SSI in lumbar spine surgeries between two different protocols of AMP.

METHODS

Data from 1597 consecutive uninfected patients who had undergone lumbar spine surgery between January 1999 and September 2004 were reviewed. The pathophysiologies among these patients included disc herniation in 686, degenerative spondylolisthesis in 340, spinal stenosis in 259, failed lumbar surgeries in 73, degenerative scoliosis in 52, isthmic spondylolisthesis in 48, spinal trauma in 34, foraminal stenosis in 27, spinal tumor in 27, and miscellaneous in 51 patients. The rate of SSI was compared between the two AMP groups. There were 1133 patients in the multiple-dose group, and 464 patients in the single-dose group. The rate of instrumentation surgery was not statistically different between the multiple-dose group (43%) and the single-dose group (39%). The overall rate of SSI was 0.7%. The SSI rate was 0.8% in the multiple-dose group and 0.4% in the single-dose group; the difference between the two was not significant. Regarding the organisms of SSI, resistant strains of bacteria were cultured in five (83.3%) of six patients in the multiple-dose group, whereas none was cultured in the single-dose group.

CONCLUSIONS

Data in the current study did not demonstrate a difference in the rate of SSI between the two different AMP protocols. Based on the CDC guideline, a single dose of AMP was proven to be efficacious for the prevention of SSI in lumbar spine surgeries. A shorter duration of first-generation cephalosporin use may effectively prevent the emergence of antibiotic-resistant bacterial infection.

Effective prevention of surgical site infection using a Centers for Disease Control and Prevention guideline-based antimicrobial prophylaxis in lumbar spine surgery

OBJECT

Antimicrobial prophylaxis (AMP) reduces the rate of surgical site infection (SSI) in lumbar spine surgery, but a great deal of variation exists regarding the timing and duration of AMP. The authors had previously used prophylactic antibiotics for 5 to 7 postoperative days. Based on the Centers for Disease Control and Prevention (CDC) guideline, the AMP period was changed to the day of surgery only. In the current study, the authors compared the rate of SSI in lumbar spine surgeries between two different protocols of AMP.

METHODS

Data from 1597 consecutive uninfected patients who had undergone lumbar spine surgery between January 1999 and September 2004 were reviewed. The pathophysiologies among these patients included disc herniation in 686, degenerative spondylolisthesis in 340, spinal stenosis in 259, failed lumbar surgeries in 73, degenerative scoliosis in 52, isthmic spondylolisthesis in 48, spinal trauma in 34, foraminal stenosis in 27, spinal tumor in 27, and miscellaneous in 51 patients. The rate of SSI was compared between the two AMP groups. There were 1133 patients in the multiple-dose group, and 464 patients in the single-dose group. The rate of instrumentation surgery was not statistically different between the multiple-dose group (43%) and the single-dose group (39%). The overall rate of SSI was 0.7%. The SSI rate was 0.8% in the multiple-dose group and 0.4% in the single-dose group; the difference between the two was not significant. Regarding the organisms of SSI, resistant strains of bacteria were cultured in five (83.3%) of six patients in the multiple-dose group, whereas none was cultured in the single-dose group.

CONCLUSIONS

Data in the current study did not demonstrate a difference in the rate of SSI between the two different AMP protocols. Based on the CDC guideline, a single dose of AMP was proven to be efficacious for the prevention of SSI in lumbar spine surgeries. A shorter duration of first-generation cephalosporin use may effectively prevent the emergence of antibiotic-resistant bacterial infection.

New treatment of lumbar disc herniation involving 5-hydroxytryptamine2A receptor inhibitor: a randomized controlled trial

OBJECT

Serotonin or 5-hydroxytryptamine (5-HT) is a chemical mediator associated with nucleus pulposus-induced radiculopathy. Inhibition of 5-HT receptors may potentially alleviate symptoms in patients with lumbar disc herniation. This prospective randomized controlled study was performed to evaluate the efficacy of the 5-HT2A receptor inhibitor in the treatment of symptomatic lumbar disc herniation.

METHODS

Forty patients with sciatica due to L4-5 or L5-S1 disc herniation were randomly allocated to treatment with the 5-HT2A inhibitor (sarpogrelate 300 mg/day) or nonsteroidal antiinflammatory drugs (NSAIDs; diclofenac 75 mg/day). Low-back pain, leg pain, and numbness were evaluated using a visual analog scale (VAS) before and after a 2-week course of treatment. The patients received only allocated medicine during the 2-week regimen and were thereafter allowed to choose any treatment options depending on their residual symptoms. One-year clinical outcomes were assessed based on the rates of additional medical interventions. The mean VAS score improvements in the 5-HT2A and NSAID groups were 33 and 46% for low-back pain, 32 and 32% for leg pain, and 35 and 22% for leg numbness, respectively. After the 2-week regimen, no additional medical interventions were required in 50% of 5-HT2A-treated patients and 15% of those receiving NSAIDs. Epidural or nerve root block procedures were performed in 35% of the 5-HT2A group and 45% of the NSAID group. Surgery was required in 20% of the 5-HT2A group and 30% of the NSAID group patients.

CONCLUSIONS

The current study provided evidence that the efficacy of the 5-HT2A inhibitor was comparable with that of NSAID therapy for lumbar disc herniation. The 5-HT2A inhibitor has the potential to alleviate symptoms in patients with lumbar disc herniation.

Non-fusion surgery for degenerative spondylolisthesis using artificial ligament stabilization: surgical indication and clinical results

STUDY DESIGN

A retrospective study.

OBJECTIVES

To report midterm clinical and radiographic results of Graf artificial ligament stabilization in the treatment of degenerative spondylolisthesis and to evaluate the role of this procedure and its surgical indications for surgical success.

SUMMARY OF BACKGROUND DATA

Nonfusion surgeries including artificial disc replacement and ligamentoplasty are increasingly gaining interest to avoid adverse effects of spinal fusion.

METHODS

Sixty-four consecutive patients with degenerative spondylolisthesis underwent artificial ligament stabilization. Surgical indication was symptomatic degenerative spondylolisthesis with <25% of vertebral slip, coronal facet tropism, and minimal disc space narrowing. Radiographic and clinical assessments were performed before surgery, immediately after surgery, and at the final follow-up. Mean follow-up period was 67 months (36-112 months).

RESULTS

Visual analog scales of low back pain and sciatic symptoms were significantly improved. Radiographic assessments demonstrated that segmental lordosis was maintained in 12.2 degrees , and flexion-extension motion was averaged 4.7 degrees at the final follow-up. Facet arthrodesis spontaneously occurred in 12 cases (18.8%) at an average of 59.5 months after surgery. Although vertebral slip was not improved, postoperative disc space narrowing was minimal. Additional surgeries were required in 4 cases for adjacent segment pathologies (6.3%). One patient (1.6%) underwent consequent spinal arthrodesis at the ligamentoplasty level.

CONCLUSIONS

Artificial ligament stabilization did not improve the vertebral slip but maintained lordosis and preserved segmental motion in 80% of patients. This procedure is an effective alternative to spinal arthrodesis in the treatment of symptomatic degenerative spondylolisthesis (Grade I) with minimal disc space narrowing and coronal facet tropism.

Pitfalls of Anterior Cervical Fusion Using Titanium Mesh and Local Autograft

Cervical fusion cages have been developed to provide an anterior structural support without harvesting tricortical iliac bone. Limited numbers of investigations have focused on pitfalls of anterior cervical fusion using cage implants. The objective of this study is to report clinical results and implant-related complications in anterior cervical fusion using titanium mesh and anterior plating. Twenty-four cases with anterior cervical fusion using a titanium mesh with local autograft and anterior plating were reviewed. One-level fusion was performed in 7 cases, and 17 patients underwent two-level fusion with corpectomy. The mean follow-up period was 27 months. Radiographic assessment included sagittal alignment, fusion status, and complications related to cage implants. Iliac bone graft harvesting was obviated in all the patients, whereas 15 patients required concomitant use of ceramic bone substitute. Sagittal alignment of the operative level was lordotic in 19 cases (79%) and neutral in 5 cases (21%) at the final follow-up. No late kyphotic collapse was observed. Twenty-three cases (96%) achieved a solid fusion, whereas the time to fusion was averaged 6.2 months. Cage subsidence frequently occurred in 42% of upper vertebrae and 50% of lower vertebrae. The use of titanium mesh and local autograft for anterior cervical fusion obviated the need for harvesting iliac bone block and provided structural anterior column support. However, it required a longer period to achieve a solid fusion when compared with tricortical iliac autograft. Cage subsidence was frequently observed in the early postoperative period.

Intraoperative biomechanical assessment of lumbar spinal instability: validation of radiographic parameters indicating anterior column support in lumbar spinal fusion

STUDY DESIGN

Lumbar spinal instability was evaluated using radiographic parameters and intraoperative biomechanical measurement.

OBJECTIVES

To validate a conventional radiographic assessment using an intraoperative biomechanical measurement and to determine the radiographic parameters indicating anterior column support in lumbar spinal fusion.

BACKGROUND

Posterior lumbar interbody fusion is gaining acceptance in the treatment of degenerative spondylolisthesis, whereas posterolateral fusion alone may result in good clinical outcomes. A quantitative biomechanical assessment of spinal instability is essential to determine the optimal method of spinal arthrodesis.

MATERIALS AND METHODS

Nineteen cases with symptomatic degenerative spondylolisthesis were included in this study. All were candidates for pedicle-screw instrumented lumbar arthrodesis. A total of five L3-L4 segments and seventeen L4-L5 segments were investigated. Radiographic assessment included disc angle, range of motion (ROM), percent of slip, and percent of posterior disc height. Distraction stiffness of the operative segment was measured intraoperatively using a strain-gauged spreader.

RESULTS

Disc angle in flexion and ROM were highly correlated to distraction stiffness. Severity of slip, disc space narrowing, and facet tropism did not influence the distraction stiffness. The cases with segmental kyphosis in flexion had significantly lower distraction stiffness than those showing segmental lordosis in flexion.

CONCLUSIONS

Disc angle in flexion and ROM were the most prognostic parameters of lumbar distraction instability. Although the option of spinal arthrodesis method should be determined based on both clinical manifestation and imaging studies, the current study demonstrated that providing of anterior column support is biomechanically reasonable for degenerative spondylolisthesis with segmental kyphosis in flexion.

Clinical results of single-level posterior lumbar interbody fusion using the Brantigan I/F carbon cage filled with a mixture of local morselized bone and bioactive ceramic granules

STUDY DESIGN

A retrospective study to evaluate the results of single-level posterior lumbar interbody fusion (PLIF) using the Brantigan I/F cage (DePuy AcroMed Corp., Raynham, MA) filled with a mixture of local morselized autologous bone and bioactive ceramic granules.

OBJECTIVES

To report the clinical and radiologic results of PLIF using the Brantigan I/F cage for lumbar degenerative pathologies with instability.

SUMMARY OF BACKGROUND DATA

The Brantigan I/F cage for PLIF was designed to improve the fusion success of interbody fusion by separating the mechanical and biologic functions of PLIF using an implant device and autologous bone from the iliac crest. Although high fusion rates have been reported, donor site morbidity caused by bone harvest from the iliac crest remains a concern. The possibility of accomplishing cage PLIF using a mixture of local morselized bone and a bone extender was studied.

METHODS

A total of 25 patients underwent single-level PLIF using the Brantigan I/F cage filled with a mixture of local morselized bone and bioactive ceramic granules. All patients were observed for more than 2 years (average 2 years 7 months) and evaluated by clinical rating and radiograph.

RESULTS

Preoperative Japanese Orthopedic Association clinical scores were significantly improved in all patients at the time of follow-up. The average improvement rate was 83.1%. There were no serious complications. Minor complications included two dural tears and two cases of thrombophlebitis. No patient required blood transfusion. All patients achieved radiographic fusion and radiographic stability, although two patients fused in a collapsed position. Regional alignment of the operated segments was restored at surgery and maintained at the time of final follow-up. There were statistical improvements in percent slip and percent posterior disc height in patients with spondylolisthesis.

CONCLUSIONS

Posterior lumbar interbody fusion using the Brantigan I/F cage with a mixture of local morselized bone and bioactive ceramic granules can yield a solid union with satisfactory regional alignment and adequate disc height without harvest of iliac crest bone.

Adjacent-segment morbidity after Graf ligamentoplasty compared with posterolateral lumbar fusion

OBJECT

Of concern to spine surgeons are accelerated degenerative changes of motion segments located above and below where spinal fusion has been performed. Graf artificial ligament stabilization has been developed to avoid the adverse effect of spinal fusion. The object of this study was to assess the adjacent-segment morbidity of Graf ligamentoplasty compared with posterolateral fusion (PF) in which instrumentation was used.

METHODS

Data obtained in 45 patients who underwent L4-5 Graf ligamentoplasty (18 patients) or PF with instrumentation (27 patients) were reviewed retrospectively. The minimum follow-up period was 5 years. In the PF group a solid fusion rate of 92.6% was achieved. Radiographic evaluation included assessment of lumbar sagittal alignment, range of motion (ROM), and adjacent-disc degeneration. Adjacent-segment morbidity was clinically assessed by determining the reoperation rate. Graf ligamentoplasty maintained regional lordosis and flexibility (13 degrees in L4-5 lordosis; 4.4 degrees in L4-5 ROM). Although there was no difference in preoperative adjacent-disc condition between the two groups, radiographic evidence of adjacent-disc deterioration was observed more frequently in patients in the PF group than the Graf group (25% and 6% at L1-2; 38% and 6% at L2-3; 38% and 18% at L3-4; and 43% and 18% at L5-sacrum, respectively). One case in the Graf group (5.6%) and five cases in the PF group (18.5%) required additional surgeries for adjacent-segment lesions.

CONCLUSIONS

Graf ligamentoplasty cannot completely replace spinal fusion. In a well-selected group of patients, however, it was shown to maintain lumbar mobility and sagittal alignment, and it decreased the risk of adjacent-segment deterioration compared with PF with instrumentation.

Mid-term clinical results of Graf stabilization for lumbar degenerative pathologies. a minimum 2-year follow-up

BACKGROUND CONTEXT

Spinal fusion has some adverse effects, such as nonunion and pain at the site of grafted bone, and fusion with rigid spinal instrumentation especially may have the possibility of increasing mechanical stress on the segments adjacent to the site of fusion. The theory of the Graf system is that it will decrease adjacent disc deterioration because of maintenance of regional lordosis with flexibility and restriction of the motion of unstable segments without rigid spinal fusion.

PURPOSE

To assess the clinical and radiologic results of Graf stabilization for lumbar degenerative disorders with minimal or mild instability.

STUDY DESIGN

This is a retrospective study examining the mid-term results of Graf stabilization.

PATIENT SAMPLE

In total, 59 patients underwent Graf ligamentoplasty and adequate decompression from April 1993 to September 1997. The subjects were 30 men and 29 women, and the mean age at the time of surgery was 60.6 years, ranging from 23 to 82 years. The average follow-up period was 3 years and 5 months, ranging from 2 years to 5 years and 10 months.

OUTCOME MEASURES

We evaluated the surgical results using a scoring system, a visual analog scale, and radiological measurements.

METHODS

The results were assessed according to a clinical scoring system established by the Japanese Orthopaedic Association (JOA score) and ratings based on a visual analog scale. Through analysis of x-ray images, the sagittal alignment (regional lordosis) and the range of motion (ROM) of the stabilized segments were measured in all cases, and the percentage of segments slipping and posterior disc height were determined for 29 patients with degenerative spondylolisthesis.

RESULTS

Clinical scores and low back pain ratings based on a visual analog scale were significantly improved at the time of final follow-up compared with the preoperative values. Regional alignment of the operative segments was maintained in lordosis at the time of final follow-up. Preoperative ROM was significantly reduced at the time of final follow-up. There were no statistical differences in percentage of slippage or percentage of posterior disc height between the final follow-up values and the preoperative values.

CONCLUSIONS

Our clinical results indicate that the Graf system is a suitable treatment option for mild and early lumbar degenerative diseases with minimum flexion instability of less than 10 degrees.