Tadao Tsujio

Characteristic Radiographic or Magnetic Resonance Images of Fresh Osteoporotic Vertebral Fractures Predicting Potential Risk for Nonunion: A Prospective Multicenter Study

Study Design. Prospective multicenter study. Objective. To identify radiographic or magnetic resonance (MR) images of fresh vertebral fractures that can predict a high risk for delayed union or nonunion of osteoporotic vertebral fractures (OVFs). Summary of Background Data. Vertebral body fractures are the most common fractures in osteoporosis patients. Conservative treatments are typically chosen for OVFs, and associated back pain generally subsides within several weeks with residual persistent deformity of the vertebral body. In some patients, OVF healing is impaired and correlated with prolonged back pain. However, assessments such as plain radiograph or MR images taken during the early phase to predict high risks for nonunions of OVFs and/or poor prognoses have not been identified. Methods. A total of 350 OVF patients from 25 institutes were enrolled in this clinical study. Plain radiograph and MR images of the OVFs were routinely taken at enrollment at the respective institutes. The findings on the plain radiograph and MR images were classified after enrollment in the study. All the patients were treated conservatively without any surgical intervention. After a 6-month follow-up, the patients were classified into two groups, a union group and a nonunion group, depending on the presence of an intravertebral cleft on plain radiograph or MR images. The associations of the images from the first visit with those of the corresponding nonunions at the 6-month follow-up were analyzed by multivariate logistic regression to elucidate specific image characteristics that may predict a high risk for nonunion of OVFs. Results. Forty-eight patients (49 vertebrae) among the 350 patients (363 vertebrae) were classified as nonunions, indicating a nonunion incidence of 13.5% for conventional conservative treatments for OVFs. The statistical analyses revealed that a vertebral fracture in the thoracolumbar spine, presence of a middle-column injury, and a confined high intensity or a diffuse low intensity area in the fractured vertebrae on T2-weighted MR images were significant risk factors for nonunion of OVFs. Conclusion. The results of this study revealed significant relationships between plain radiograph and MR images of acute phase OVFs and the incidence of nonunion. As these risk factors are defined more clearly and further validated, they may become essential assessment tools for determining subsequent OVF treatments. Patients with one or more of the earlier-described risk factors for nonunion should be observed carefully and provided with more intensive treatments.

Risk factor analysis for motor deficit and delayed recovery associated with L4/5 lumbar disc herniation.

Study Design Retrospective study of multivariable analysis for the risk factors of motor deficit associated with lumbar disc herniation (LDH). Objectives To identify the risk factors for motor deficit and delayed recovery after surgery in patients with LDH. Summary of Background Data LDH can cause motor deficit as well as pain and sensory disturbance. Even though motor deficit can lead to disabilities and affect treatment plans, few studies have described motor deficit and its risk factors in LDH patients. Methods Seventy-six consecutive patients who underwent microsurgical or microendoscopic discectomy for LDH at the L4/5 level were retrospectively reviewed. Motor deficit was defined as tibialis anterior muscle strength of lower than grade 4 by the manual muscle test, and delayed recovery was defined as cases requiring longer than 3 months to achieve complete recovery. The possible risk factors including sex, age, symptom duration, preoperative radiographic parameters, and type of herniation were evaluated by multivariate logistic regression analysis. Results Forty-three patients (56.6%) suffered from motor deficit before surgery. Forty cases (93%) completely recovered within a mean duration of 4 months. Multivariate logistic regression analysis revealed that noncontained-type (P=0.012, odds ratio=13.7) and migrated herniated nucleus pulposus (P=0.033, odds ratio=9.8) were important risk factors for motor deficit. Furthermore, severe motor deficit (preoperative manual muscle test⩽3; P=0.019, odds ratio=19.6) and noncontained type (P=0.049, odds ratio=5.17) were identified as important risk factors for delayed recovery. Conclusions Noncontained-type or migrated herniated nucleus pulposus seem to be the most important risk factors for motor deficit in LDH, whereas severe motor deficit and noncontained type seem to be associated with delayed recovery. The treatment options for patients with these factors at first visit should be carefully chosen during the follow-up period.

The influence of approach side on facet preservation in microscopic bilateral decompression via a unilateral approach for degenerative lumbar scoliosis. Clinical article.

OBJECT The authors compared the clinical outcomes of microscopic bilateral decompression via a unilateral approach (MBDU) for the treatment of degenerative lumbar scoliosis (DLS) and for lumbar canal stenosis (LCS) without instability. The authors also compared postoperative spinal instability in terms of different approach sides (concave or convex) following the procedure. METHODS The authors retrospectively reviewed data obtained in 50 consecutive patients (25 in the DLS group and 25 in the LCS group) who underwent MBDU; the minimum follow-up period was 2 years. Patients with DLS were divided into 2 subgroups according to the surgical approach side: a concave group (23 segment) and a convex group (17 segments). The Japanese Orthopaedic Association Scale scores for the assessment of low-back pain were evaluated before surgery and at final follow-up. The Japanese Orthopaedic Association Scale scores and recovery rates were compared between the DLS and LCS groups, and between the convex and concave groups. Cobb angle and scoliotic wedging angle (SWA) were evaluated on standing radiographs before surgery and at final follow-up. Facet joint preservation (the percentage of preservation) was assessed on pre- and postoperative CT scans, compared between the LCS and DLS groups, and compared between the concave and convex groups. The influence of approach side on postoperative progression of segmental instability was also examined in the DLS group. RESULTS The mean recovery rate was 58.7% in the DLS and 62.0% in the LCS group. The mean recovery rate was 58.6% in the convex group and 60.6% in the concave group. There were no significant differences in recovery rates between the LCS and DLS groups, or between the DLS subgroups. The mean Cobb angles in the DLS group were significantly increased from 12.7° preoperatively to 14.1° postoperatively (p < 0.05), and mean preoperative SWAs increased significantly from 6.2° at L3-4 and 4.1° at L4-5 preoperatively to 7.4° and 4.9°, respectively, at final follow-up (p < 0.05). There was no significant difference in percentage of preservation between the DLS and LCS groups. The mean percentages of preservation on the approach side in the DLS group at L3-4 and L4-5 were 89.0% and 83.1% in the convex group, and those in the concave group were 67.3% and 77.6%, respectively. The percentage of preservation at L3-4 was significantly higher in the convex than the concave group. The mean SWA had increased in the concave group (p = 0.01) but not the convex group (p = 0.15) at final follow-up. CONCLUSIONS The MBDU can reduce postoperative segmental spinal instability and achieve good postoperative clinical outcomes in patients with DLS. The convex approach provides surgeons with good visibility and improves preservation of facet joints.

Prognostic Factors for Reduction of Activities of Daily Living Following Osteoporotic Vertebral Fractures

Study Design. Prospective cohort study. Objective. To elucidate the prognostic factors indicating reduced activities of daily living (ADL) at the time of the 6-month follow-up after osteoporotic vertebral fracture (OVF). Summary of Background Data. OVF has severe effects on ADL and quality of life (QOL) in elderly patients and leads to long-term deteriorations in physical condition. Many patients recover ADL with acceleration of bony union and spinal stability, but some experience impaired ADL even months after fracture. Identifying factors predicting reduced ADL after OVF may prove valuable. Methods. Subjects in this prospective study comprised 310 OVF patients from 25 institutes. All patients were treated conservatively without surgery. Pain, ADL, QOL, and other factors were evaluated on enrollment and at 6 months. ADL were evaluated using the criteria of the Japanese long-term care insurance system to evaluate the degree of independence. We defined reduced ADL as a reduction of at least single grade at 6 months after fracture and investigated factors predicting reduced ADL after OVF, using uni- and multivariate regression analysis. Results. ADL were reduced at 6 months after OVF in 66 of 310 patients (21.3%). In univariate analysis, age more than 75 years (P = 0.044), female sex (P = 0.041), 2 or more previous spine fractures (P = 0.009), presence of middle column injury (P = 0.021), and lack of regular exercise before fracture (P = 0.001) were significantly associated with reduced ADL. In multivariate analysis, presence of middle column injury (odds ratio [OR], 2.26; P = 0.022) and lack of regular exercise before fracture (OR, 2.49; P = 0.030) were significantly associated with reduced ADL. Conclusion. These results identified presence of middle column injury of the vertebral body and lack of regular exercise before fracture as prognostic factors for reduced ADL. With clarification and validation, these risk factors may provide crucial tools for determining subsequent OVF treatments. Patients showing these prognostic factors should be observed carefully and treated with more intensive treatment options.

Impact of initial conservative treatment interventions on the outcomes of patients with osteoporotic vertebral fractures.

Study Design. Prospective multicenter study. Objective. To examine whether initial conservative treatment interventions for osteoporotic vertebral fractures (OVF) influence patient outcomes. Summary of Background Data. OVFs have been described as stable spinal injuries and, in most cases, are managed well with conservative treatment. However, systematic treatments for OVF have not been clearly established. Methods. A total of 362 patients with OVF (59 males and 303 females; mean age, 76.3 yr) from 25 institutes were enrolled in this clinical study. All the patients were treated conservatively without any surgical interventions. The patient outcomes were evaluated 6 months after the fractures on the basis of Short Form-36 (SF-36) physical component summary (PCS) and mental component summary (MCS), activities of daily living (the Japanese long-term care insurance system), back pain (visual analogue scale), cognitive status (mini-mental state examination), and vertebral collapse, which were used as response variables. Furthermore, brace type, hospitalization, bisphosphonates after injury, and painkillers after injury were explanatory variables for the treatment interventions. To evaluate the independent effects of treatment interventions on patient outcomes, we performed multivariate logistic regression analyses and obtained odds ratios that were adjusted for the potential confounding effects of age, sex, level of fracture, presence of middle-column injury, pain visual analogue scale at enrollment, mini-mental state examination score at enrollment, and previous use of steroids. Results. There was no significant difference for treatment intervention factors including brace type, hospitalization, bisphosphonates after injury, and painkillers after injury. For adjusting factors, the presence of middle-column injury was significantly associated with SF-36 PCS ⩽ 40, reduced activities of daily living, prolonged back pain, and vertebral collapse. Female sex and advanced age were associated with SF-36 PCS ⩽ 40. Low mini-mental state examination scores at enrollment were associated with SF-36 PCS ⩽ 40 and reduced activities of daily living. The previous use of steroids was associated with SF-36 MCS ⩽ 40, prolonged back pain, and vertebral collapse. No other examined variables were significant risk factors for patient outcomes. Conclusion. These results showed that treatment intervention factors did not affect patient outcomes 6 months after OVF. Middle-column injury was a significant risk factor for both clinical and radiological outcomes. In the future, establishing systematic treatments for cases with middle-column injuries is needed. Level of Evidence: 2

High serum levels of menatetrenone in male patients with ossification of the posterior longitudinal ligament.

Study Design. This work was performed to investigate the role of vitamin K (VK) in the pathogenesis of ossification of posterior longitudinal ligament (OPLL), by analyzing the biochemical markers of the blood samples of OPLL patients and responses of ligament cells derived from OPLL lesion to VK2. Objectives. The pathogenesis of OPLL, classified as a form of diffuse idiopathic skeletal hyperostosis, is still unclear. In this study, we investigated the role of menaquinone (VK2) in patients with OPLL (OPLL patients) and the effects of VK2 on ligament cells isolated from OPLL lesion. Methods. Serum levels of intact osteocalcin, glu-osteocalcin, MK-4, -7 (VK2 variants) and other minerals in spot blood samples were measured in 24 OPLL patients and in 24 age-matched control patients (non-OPLL patients). The cultured cells isolated from an OPLL patient were treated with MK-4. Alkaline phosphatase (Al-p) activity and osteocalcin release were measured after 2 weeks of culture. Results. In the clinical study, the serum MK-4 in male OPLL patients was significantly higher than that in male non-OPLL patients. However, among female patients, the difference was not significant. Although the serum osteocalcin in females was significantly higher than that in males, there was no significant difference between the OPLL and non-OPLL groups. In in vitro study, MK-4 did not increase Al-p activity in the ligament cells isolated from nonossified region of OPLL patient. Osteoblastic activity of the cultured cells was not stimulated by MK-4. Conclusion. From these results and previous reports, we propose the possibility of the impediment in VK2 metabolism in OPLL patients. The results also implicate the gender tendency in OPLL, because the difference of serum level of MK-4 in OPLL patients was significant only in male.

Waterless Hand Rub Versus Traditional Hand Scrub Methods for Preventing the Surgical Site Infection in Orthopedic Surgery

Study Design. A retrospective cohort study with prospectively collected data. Objective. The aim of this study was to compare SSI incidences, the cost of hand hygiene agents, and hand hygiene time between the traditional hand scrub and the waterless hand rub protocols before orthopedic surgery. Summary of Background Data. Surgical site infections (SSI) prolong hospitalization and are a leading nosocomial cause of morbidity and a source of excess cost. Recently, a waterless hand rub protocol comprising alcohol based chlorhexidine gluconate for use before surgery was developed, but no studies have yet examined its utility in orthopedic surgery. Methods. Fourteen hundred consecutive patients who underwent orthopedic surgery (spine, joint replacement, hand, and trauma surgeries) in our hospital since April 1, 2012 were included. A total of 712 cases underwent following traditional hand scrub between April 1, 2012 and April 30, 2013 and 688 cases underwent following waterless hand rub between June 1, 2013 and April 30, 2014. We compared SSI incidences within all and each subcategory between two hand hygiene protocols. All patients were screened for SSI within 1 year after surgery. We compared the cost of hand hygiene agents and hand hygiene time between two groups. Results. The SSI incidences were 1.3% (9 of 712) following the traditional protocol (2 deep and 7 superficial infections) and 1.1% (8 of 688) following the waterless protocol (all superficial infections). There were no significant differences between the two groups. The costs of liquids used for one hand hygiene were about

FACTORS PREDICTIVE OF PSEUDOARTHROSIS FOLLOWING OSTEOPOROTIC VERTEBRAL FRACTURE- A PROSPECTIVE MULTICENTER STUDY

2 for traditional hand scrub and less than

Factors affecting neurological deficits and intractable back pain in patients with insufficient bone union following osteoporotic vertebral fracture

1 for waterless hand rub. The mean hand hygiene time was 264 seconds with the traditional protocol and 160 seconds with the waterless protocol. Conclusion. Waterless hand rub with an alcohol based chlorhexidine gluconate solution can be a safe, quick, and cost-effective alternative to traditional hand scrub. Level of Evidence: 3

Endoscopic vertebroplasty for the treatment of chronic vertebral compression fracture. Technical note.

Introduction. The purpose of this study was to determine the incidence of non-union following osteoporotic vertebral fracture and prognostic factors associated with non-union on imaging modalities. Methods. One hundred and fortyfive patients with 150 osteoporotic vertebral fractures from twenty-five institutions who had completed six-month follow-up were included in this study. At the time of entry, the patients underwent plain X-ray examination and magnetic Resonance Imaging (MRI). At 6-month follow-up, all patients were examined again with plain X-ray and MRI. Based on X-ray findings of the presence of an intravertebral cleft, patients were classified into two groups: a bone union group and a non-union group. Plain X-ray and MRI findings at time of entry were evaluated in both groups to elucidate prognostic factors associated with non-union after osteoporotic vertebral fracture. Results. A total of 129 cases were classified in the bone union group and 21 in the non-union group, yielding a non-union rate at 6month follow-up of 14.0%. All of the cases of non-union were associated with fracture at the thoraco-lumbar level, and the most frequent level of fracture was T12. The type of fracture pattern on plain X-ray was not related to prognosis. On MRI, high intensity-local type change on T2-weighted images was most commonly associated with non-union (70.0%). Low intensity-total type had the next highest rate of development of non-union (25.5%). Of fractures with middle column injury, 23.9% exhibited non-union group, while of fractures without middle column injury 9.6% exhibited non-union. This difference was statistically significant. Conclusions. 1. The rate of non-union following osteoporotic vertebral fracture was 14.0% in the present prospective study. 2. Fracture in the thoracolumbar area, middle column injury, and local high-intensity change or overall low-intensity change on T2-weighted images were factors predictive of non-union. I N T E R N A T I O N A L S O C I E T Y F O R T H E S T U D Y O F L U M B A R S P I N E