Impact of surgical treatment on lipid metabolism in patients with lumbar spinal disorders: Prospective observational study.

PURPOSE: It is still unclear how lumbar spinal surgery affects the lipid metabolism of patients with lumbar spinal disorders (LSDs) such as lumbar spinal canal stenosis and lumbar disk herniation. The present study aimed to assess the impact of lumbar spinal surgery on lipid metabolism in patients with LSDs and clarify the factors associated with changes in visceral fat (VF) accumulation before and after lumbar spinal surgery. METHODS: Consecutive patients with lumbar spinal surgery for LSDs were prospectively included. Abdominal computed tomography images and blood examination of the participants were evaluated before surgery and at 6 months and 1 year after surgery. The cross-sectional VF area (VFA) was measured at the level of the navel using computed tomography images. Blood examination items included triglycerides and high-density lipoprotein (HDL). RESULTS: The study enrolled a total of 138 patients. Female patients with LSDs had significantly increased VFA and serum triglyceride levels after lumbar spinal surgery. On multivariable analysis, the group with > 100 cm2 of preoperative VFA and a postoperative decrease in VFA had a significantly worse preoperative walking ability based on the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (relative risk 2.1; 95% confidence intervals 1.1-4.1). CONCLUSIONS: The present study demonstrated that patients with LSDs did not necessarily improve their lipid metabolism after lumbar spinal surgery. Instead, female patients with LSDs had significantly deteriorated lipid metabolism after lumbar spinal surgery. Finally, a worse preoperative walking ability was associated with the improvement in excess VF accumulation after lumbar spinal surgery.

Seasonal variation in incidence and causal organism of surgical site infection after PLIF/TLIF surgery: A multicenter study.

BACKGROUND: Postoperative SSI is a common and potentially serious complication in spine surgery. Seasonal variation occurs in rates of nosocomial infection, with higher rates found in the summer, during which hot, humid conditions may be optimal for proliferation of bacteria. This might also influence the rate of SSI. The purpose of the study was to examine seasonal variation in SSI after PLIF/TLIF surgery, including relationships with experience of surgeons and causal organisms. METHODS: Cases with SSI after PLIF/TLIF surgery at 10 facilities between January 1, 2012, and December 31, 2014 were retrieved from a database. Infection was defined based on CDC guidelines for SSIs. Patients were followed for at least two years after surgery. Surgeries were examined in spring (April-June), summer (July-September), autumn (October-December), and winter (January-March). Seasonal variation and other factors with a potential association with SSIs were evaluated. RESULTS: A total of 1174 patients (607 males, 567 females) who underwent PLIF/TLIF surgery were identified. The operations were PLIF (n = 667), TLIF (n = 443), MIS-PLIF (n = 27), and MIS-TLIF (n = 37). The total SSI rate for the 2-year period was 2.5% (29/1174), and the 2-year average SSI rates for surgeries in each season were spring, 2.6% (7/266); summer, 3.9% (13/335); fall, 1.3% (4/302); winter, 1.8% (5/271). The SSI rate was significantly higher in summer than non-summer (3.9% vs. 1.9%, p < 0.05). SSIs were caused by a variety of pathogens, including Gram-positive cocci, and Staphylococcus aureus was the most common pathogenic organism to cause SSI. CONCLUSION: Seasonality should be taken into account in strategies for SSI prevention, with particular attention on mitigation of increased temperature and humidity in the summer and on infection caused by Gram-positive cocci and S. aureus.

Reoperation within 2 years after lumbar interbody fusion: a multicenter study.

PURPOSE: Posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) can have complications that require reoperation. The goal of the study was to identify risk factors for reoperation within 2 years after PLIF/TLIF. METHODS: A retrospective analysis of a prospective multicenter database was performed for patients who underwent PLIF/TLIF. A total of 1363 patients (689 males and 674 females) were identified, with an average age of 65.9 years old. Comorbidities, perioperative ASA grade, and operative factors were compared between patients with and without reoperation. Risk factors for reoperation were identified in multivariate logistic analysis. RESULTS: There were 38 reoperations within 2 years after PLIF/TLIF (2.8%). The original surgical procedures were open PLIF (n = 26), open TLIF (n = 10), and minimally invasive surgery (n = 2). Reoperation was due to adjacent segment degeneration (ASD) (n = 10), surgical site infection (SSI) (n = 9), screw misplacement (n = 6), postoperative epidural hematoma (n = 6), pseudoarthrosis (n = 4), and cage protrusion (n = 3). Number of levels fused and dural tear were significantly associated with reoperation. In analysis of complications requiring reoperation, SSI was related to diabetes mellitus and dural tear, and postoperative epidural hematoma was related to fusion of two or more levels, EBL, and operation time. In multivariate logistic regression, fusion of two or more levels (HR 2.19) was significantly associated with reoperation. CONCLUSION: Surgical invasiveness, as reflected by number of fused levels, operation time, EBL and dural tear, was associated with reoperation. Fusion of two or more levels is a strong risk factor for reoperation within 2 years after initial PLIF/TLIF. These slides can be retrieved under Electronic Supplementary Material.

Three-dimensional Magnetic Resonance Imaging of the Anterolateral Ligament of the Knee: An Evaluation of Intact and Anterior Cruciate Ligament-Deficient Knees From the Scientific Anterior Cruciate Ligament Network International (SANTI) Study Group.

PURPOSE: To determine the visualization rate of the anterolateral ligament (ALL) in uninjured and anterior cruciate ligament (ACL)-deficient knees using 3-dimensional (3D) magnetic resonance imaging (MRI) and to characterize the spectrum of ALL injury observed in ACL-deficient knees, as well as determine the interobserver and intraobserver reliability of a 3D MRI classification of ALL injury. METHODS: A total of 100 knees (60 ACL deficient and 40 uninjured) underwent 3D MRI. The ALL was evaluated by 2 blinded orthopaedic surgeons. The ALL was classified as follows: type A, continuous, clearly defined low-signal band; type B, warping, thinning, or iso-signal changes; and type C, without clear continuity. The comparison between imaging performed early after ACL injury (<1 month) and delayed imaging (>1 month) was evaluated, as was intraobserver and interobserver reliability. RESULTS: Complete visualization of the ALL was achieved in all uninjured knees. In the ACL-deficient group, 24 knees underwent early imaging, with 87.5% showing evidence of ALL injury (3 normal, or type A, knees [12.5%], 18 type B [75.0%], and 3 type C [12.5%]). The remaining 36 knees underwent delayed imaging, with 55.6% showing evidence of injury (16 type A [44.4%], 18 type B [50.0%], and 2 type C [5.6%]). The difference in the rate of injury between the 2 groups was significant (P = .03). Multivariate analysis showed that the delay from ACL injury to MRI was the only factor (negatively) associated with the rate of injury to the ALL. Interobserver reliability and intraobserver reliability of the classification of ALL type were good (κ = 0.86 and κ = 0.93, respectively). CONCLUSIONS: Three-dimensional MRI allows full visualization of the ALL in all normal knees. The rate of injury to the ALL in acutely ACL-injured knees identified on 3D MRI is higher than previous reports using standard MRI techniques. This rate is significantly higher than the rate of injury to the ALL identified on delayed imaging of ACL-injured knees. LEVEL OF EVIDENCE: Level IV, diagnostic, case-control study.

[Visualization of Anterolateral Ligament of the Knee Using 3D Reconstructed Variable Refocus Flip Angle-Turbo Spin Echo T2 Weighted Image].

Anterolateral ligament (ALL) is one of the lateral structures in the knee that contributes to the internal rotational stability of tibia. ALL has been referred to in some recent reports to re-emphasize its importance. We visualized the ALL on 3D-MRI in 32 knees of 27 healthy volunteers (23 male knees, 4 female knees; mean age: 37 years). 3D-MRIs were performed using 1.5-T scanner [T(2) weighted image (WI), SPACE: Sampling Perfection with Application optimized Contrast using different flip angle Evolutions] in the knee extended positions. The visualization rate of the ALL, the mean angle to the lateral collateral ligament (LCL), and the width and the thickness of the ALL at the joint level were investigated. The visualization rate was 100%. The mean angle to the LCL was 10.6 degrees. The mean width and the mean thickness of the ALL were 6.4 mm and 1.0 mm, respectively. The ALL is a very thin ligament with a somewhat oblique course between the lateral femoral epicondyle and the mid-third area of lateral tibial condyle. Therefore, the slice thickness and the slice angle can easily affect the ALL visualization. 3D-MRI enables acquiring thin-slice imaging data over a relatively short time, and arbitrary sections aligned with the course of the ALL can later be selected.

Surgically treated cases of lumbar spondylolysis and isthmic spondylolisthesis: a multicenter study.

STUDY DESIGN: Prospective database study. OBJECTIVES: To grasp the characteristics of surgically treated cases with lumbar spondylolysis or isthmic spondylolisthesis. SUMMARY OF BACKGROUND DATA: A detailed analysis of surgically treated cases with spondylolysis or isthmic spondylolisthesis has never been reported. An epidemiological study in Japan conducted on 2000 subjects found the incidence of lumbar spondylolysis in the Japanese general population (population-based study) to be 5.9% (males: 7.9%, females: 3.9%). Among 124 vertebrae with spondylolysis, there were 0.8% L2 lesions, 3.2% L3 lesions, 5.6% L4 lesions, and 90.3% L5 lesions, including 5 cases (4.3%) with multiple-level lesions. METHODS: We have been registering surgically treated spine cases in our database since 2000. From this database, we prospectively collected cases with lumbar spondylolysis or isthmic spondylolisthesis that were treated surgically between January 2000 and December 2009. We determined the age at surgery, sex, and vertebral level of spondylolysis. RESULTS: Of the 564 spondylolysis patients treated surgically, 66.8% were male and 33.2% were female. The mean age at surgery was 52.5 years (range, 13-84 y). There were 585 vertebrae with spondylolysis including 21 cases (3.7%) with multiple-level lesions. L5 spondylolysis affected 432 vertebrae and was the most common location (73.8%), followed by 125 L4 lesions (21.4%), 24 L3 lesions (4.1%), and 2 L2 lesions (0.7%). CONCLUSIONS: The percentage of L4 lesions in our study was significantly higher and of L5 lesions was significantly lower than those lesions' percentages in the population-based study. L4 spondylolysis may be more unstable or cause clinical symptoms more frequently leading to more surgical intervention. The percentage of multiple-level spondylolysis was similar between the 2 studies, suggesting these patients respond relatively well to conservative treatment. The male/female ratio was 2:1 in both studies, indicating that males and females require surgery at a similar frequency.

Appropriate timing of surgical intervention for the proximal type of cervical spondylotic amyotrophy.

PURPOSE: The purposes of this study were to evaluate the clinical outcome after surgical treatment of patients with the proximal type of cervical spondylotic amyotrophy (CSA) and to explore the appropriate timing for surgical intervention. MATERIALS AND METHODS: A retrospective review was performed on a consecutive cohort of 41 patients who underwent surgical treatment for the proximal type of CSA between 1995 and 2011 at the Nagoya Spine Group Hospitals. We collected information regarding age, type of muscle atrophy, preoperative and final manual muscle test, duration of symptoms, high-intensity areas on T2-weighted MRI images, low-intensity areas on T1-weighted MRI images, levels of spinal canal stenosis, the compression lesion site, cervical kyphosis and surgical procedures (laminoplasty, anterior spinal fusion and posterior spinal fusion). Univariate analyses and multivariate logistic regression analysis were performed to identify correlates of a poor outcome. To explore the appropriate timing for performing surgery, we analyzed the data using receiver operating characteristic (ROC) analysis. RESULTS: The duration of CSA symptoms was 11.6 months on average. The surgical results were excellent for 25 patients, good for six, fair for nine and poor for one. On multivariate logistic regression analysis, the duration of symptoms was statistically associated with a poor surgical outcome (OR 1.393, p = 0.011). ROC analysis demonstrated that 4.3 months from the onset of CSA symptoms was the appropriate time to undergo surgery. CONCLUSIONS: Our results indicate that we should recommend surgical intervention to patients with the proximal type of CSA within about 4 months after the onset of symptoms if conservative treatment has not been successful.

Nationwide investigation into adverse tissue reactions to metal debris after metal-on-metal total hip arthroplasty in Japan.

BACKGROUND: Adverse reactions to metal debris (ARMD) after receiving metal-on-metal (MoM) hip implants is a recent concern. However, no epidemiologic study has examined ARMD for MoM hip implants in Japan. The purposes of this study were to research the incidence of ARMD and to identify poorly performing MoM hip implants in Japan. METHODS: From 2000 to 2011, 7 companies provided 23,226 MoM implants in Japan. A questionnaire regarding ARMD was sent to 101 hospitals at which 62% of the 23,226 MoM implants had been used. RESULTS: Replies to the questionnaire were received from 82 hospitals. In these hospitals, surface hip replacement types (SRs) were used in 606 hips and stemmed types were used in 12,961 hips. ARMD were reported in 3 hips (0.5%) with SRs and 160 hips (1.2%) with stemmed types. ARMD in the 3 hips with SRs were asymptomatic and no revisions were performed. Among AMRD with stemmed implants, revision was performed in 83 hips and excision of an ARMD lesion was performed in 3 hips. The remaining 74 hips were asymptomatic and careful follow-up was continued. A significant difference in reoperation rate was evident between SRs (0%) and stemmed types (0.7%). Incidences of ARMD were significantly higher with Ultamet (P = 0.005), Conserve (P < 0.001), and Cormet (P < 0.001) MoM bearing couples than with Metasul bearings. CONCLUSIONS: The incidence of ARMD in large surgical volume hospitals in Japan from 2000 to 2011 was estimated to be 0.5% with SRs and 1.2% with stemmed types. The reoperation rate was significantly higher with stemmed types than with SRs. Three brands of MoM stemmed implants were identified as showing a higher incidence of ARMD.

Predictors of Patient Dissatisfaction after Lumbar Spinal Canal Stenosis Surgery: A Multicenter Retrospective Study.

Introduction: Recently, patient satisfaction has gained prominence as a crucial measure for ensuring patient-centered care. Furthermore, patient satisfaction after lumbar spinal canal stenosis (LCS) surgery is an important metric for physician's decision of surgical indication and informed consent to patient. This study aimed to elucidate how patient satisfaction changed after LCS surgery to identify factors that predict patient dissatisfaction. Methods: We retrospectively reviewed time-course data of patients aged ≥40 years who underwent LCS surgery at multiple hospitals. The participants completed the Zurich Claudication Questionnaire (ZCQ) and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) before surgery and then 6 months and 1 year postsurgery. Patient satisfaction was categorized according to the postoperative score of the satisfaction domain of the ZCQ: satisfied, score ≤2.0; moderately satisfied, 2.0< score ≤2.5; and dissatisfied, score >2.5. Results: The study enrolled 241 patients. Our data indicated a satisfaction rate of around 70% at 6 months and then again 1 year after LCS surgery. Among those who were dissatisfied 6 months after LCS surgery, 47.6% were more satisfied 1 year postsurgery. Furthermore, 86.2% of those who were satisfied 6 months after LCS surgery remained satisfied at 1 year. Multivariable analysis revealed that age (relative risk, 0.5; 95% confidence interval, 0.2-0.8) and preoperative score of psychological disorders on the JOABPEQ (relative risk, 0.2; 95% confidence interval, 0.03-0.08) were significantly associated with LCS surgery dissatisfaction. In addition, the receiver operating characteristic curve analysis revealed that the cutoff value for the preoperative score of psychological disorder of the JOABPEQ was estimated at 40 for LCS surgery dissatisfaction. Conclusions: Age and psychological disorders were identified as significant predictors of dissatisfaction, with a JOABPEQ cutoff value providing potential clinical applicability.

Bone union rate with autologous iliac bone versus local bone graft in posterior lumbar interbody fusion (PLIF): a multicenter study.

PURPOSE: The purpose of this study is to compare bone union rate between autologous iliac bone and local bone graft in patients treated by posterior lumbar interbody fusion (PLIF) using carbon cage for single level interbody fusion. METHODS: The subjects were 106 patients whose course could be observed for at least 2 years. The diagnosis was lumbar spinal canal stenosis in 46 patients, herniated lumbar disk in 12 patients and degenerative spondylolisthesis in 51 patients. Single interbody PLIF was done using iliac bone graft in 53 patients and local bone graft in 56 patients. Existence of pseudo-arthrosis on X-P (AP and lateral view) was investigated during the same follow up period. RESULTS: No significant differences were found in operation time and blood loss. Significant differences were also not observed in fusion grade at any follow up period or in fusion progression between the two groups. Donor site pain continued for more than 3 months in five cases (9%). The final fusion rate was 96.3 versus 98.3%. CONCLUSIONS: Almost the same results in fusion were obtained from both the local bone group and the autologous iliac bone group. Fusion progression was almost the same. Complications at donor sites were seen in 19% of the cases. From the above results, it was concluded that local bone graft is as beneficial as autologous iliac bone graft for PLIF at a single level.

Risk factors for a poor outcome following surgical treatment of cervical spondylotic amyotrophy: a multicenter study.

INTRODUCTION: Cervical spondylotic amyotrophy (CSA) is characterized by muscle atrophy in the upper extremities without gait disturbance. However, the indications and outcomes of surgical treatment for CSA have not been clarified. The purpose of this study was to determine the risk factors for a poor outcome following surgical treatment of CSA. MATERIALS AND METHODS: We performed a retrospective review of CSA in patients from 1991 to 2010 through a multicenter study. We collected information regarding age, type of muscle atrophy, preoperative manual muscle test (MMT), duration of symptoms, high-intensity areas on T2-weighted MR images, low-intensity areas on T1-weighted MR images, levels of spinal canal stenosis, cervical kyphosis and surgical procedures (laminoplasty, anterior cervical discectomy and fusion and posterior spinal fusion), and calculated overall risk factors related to a poor outcome following surgery. Univariate analyses and multivariate logistic regression analysis were performed to identify correlates of a poor outcome. RESULTS: Fifty-nine patients, 95 % male (56 patients), were included in our analysis with a mean age of 59 years (range 32-78 years). Eighteen patients did not improve after surgery. Symptom duration (OR = 1.263), preoperative MMT grade (OR = 0.169) and distal type of CSA (OR = 9.223) were all associated with an increased risk of a poor surgical outcome. CONCLUSION: Early surgery is recommended for CSA patients in whom conservative treatment has not been successful. We also recommend surgery for patients who have severe preoperative muscle weakness or have the distal type of CSA.

Remodeling of heat-treated cortical bone allografts for posterior lumbar interbody fusion: serial 10-year follow-up.

We have selected heat-treated bone allografts as the graft material since the Tokai Bone Bank, the first regional bone bank in Japan, was established in 1992. In this study, we examined changes in bone mineral density (BMD), and morphology observed by magnetic resonance imaging (MRI), and histological findings of bone grafts in cases followed up for 7-10 years after bone grafting to grasp the remodeling of heat-treated cortical bone allografts for posterior lumber interbody fusion (PLIF). BMD of bone grafts was reduced by half at 10 years after grafting. MRI revealed that bone grafts were indistinguishable initially in only 22.2% of cases, whereas after a lengthy period of 10 years distinguishable in many cases. Histologically, new bone formation at the graft-host interface was observed earlier, at 1 year after grafting, than that at the periphery of canals in the specimens. The laminated structure of the cortical bone eroded over time, and fragmented bone trabeculae were observed in the specimens at 8 years or longer after grafting, though necrotic bone still remained in some sites.

Incidence of complications associated with spinal endoscopic surgery: nationwide survey in 2007 by the Committee on Spinal Endoscopic Surgical Skill Qualification of Japanese Orthopaedic Association.

BACKGROUND: This report was conducted to elucidate the current status of spinal endoscopic surgery and relevant incidents through analysis of the results of a questionnaire survey conducted in 2007 by the Committee on Spinal Endoscopic Surgical Skill Qualification of the Japanese Orthopaedic Association (JOA). METHODS: Questionnaire forms were sent to 2011 training facilities nationwide certified by the JOA, and 1082 of these facilities returned the filled questionnaires (response rate 53.8%). Of these facilities, 257 (23.8% of the responding facilities) undertook spinal endoscopic surgery in 2007. These institutions were asked to fill in the survey form with the details of the operations and relevant incidents as well as the incident levels. RESULTS: In total, the 257 facilities performed 6239 spinal endoscopic surgeries during 2007. Posterior spinal endoscopic surgery constituted most of the operations (6217 cases, 98.2%) including 4336 cases of microendoscopic discectomy (MED), 1273 cases of microendoscopic laminectomy or fenestration, and 379 cases of transforaminal or posterior lumbar interbody fusion. The total number of incidents was 133 (2.13%). The numbers of incidents by operative method were 75 (56.4%) during MED, 57 (42.9%) during microendoscopic laminectomy or fenestration, and 1 (0.8%) during interbody fusion. Of 133 incidents, dural tear occurred in 99 (74.4%), injury of the cauda equina or a nerve root in 7 (5.3%), facet fracture in 7 (5.3%), hematoma and wrong level in 6 each (4.5%), and wrong side and bedsore in 1 each (0.8%). The incident level was level 1 in 6, level 2 in 24, level 3a in 82, level 3b in 16, level 4 in 5, and level 5 (fatal) in 0. CONCLUSIONS: The results of this survey revealed an increasing trend of spinal endoscopic surgery and a decreasing trend of the complication rates. The complication rates of spinal endoscopic surgery were not higher than those of conventional surgery, indicating the safety of this surgical method.

Predictors of Prolonged Length of Stay After Lumbar Interbody Fusion: A Multicenter Study.

STUDY DESIGN: Retrospective analysis of a prospectively database. OBJECTIVES: To identify factors associated with prolonged length of stay (LOS) in posterior /transforaminal lumbar interbody fusion (PLIF/TLIF). METHODS: The subjects were patients who underwent PLIF/TLIF at 10 facilities from 2012 to 2014. A total of 1168 such patients with a mean age of 65.9 ± 12.5 years (range 18-87 years) were identified in the database. Operations were PLIF (n = 675), TLIF (n = 443), minimally invasive surgery (MIS)-PLIF (n = 22), and MIS-TLIF (n = 32). Age, gender, body mass index, ambulatory status, comorbidities, perioperative American Society of Anesthesiologists (ASA) grade, operative factors, and complications were examined. LOS was defined as the number of calendar days from the operation to hospital discharge. LOS was categorized as normal (<75th percentile) or prolonged (≥75th percentile). RESULTS: The average LOS was 20.8 ± 9.8 days (range 7-77 days). There was a significant correlation between LOS and age (P < .05). Reoperation during hospitalization was performed in 20 cases for surgical site infection (n = 12), epidural hematoma (n = 5), and screw misplacement (n = 3). In multivariate analysis, prolonged LOS was associated with preoperative variables of age ≥70 years (odds ratio [OR] 1.87, 95% CI 1.38-2.54), and ASA class ≥III (OR 1.52, 95% CI 1.04-2.25); surgical variables of open procedures (OR 5.84, 95% CI 1.74-19.63), fused levels ≥3 (OR 5.17, 95% CI 3.17-8.43), operative time ≥300 minutes (OR 1.88, 95% CI 1.15-3.07), and estimated blood loss ≥500 mL (OR 1.71, 95% 1.07-2.75). CONCLUSIONS: The factors identified in this study should help with obtaining informed consent, surgical planning and complication prevention to reduce health care costs associated with prolonged LOS.

Trends of postoperative length of stay in spine surgery over 10 years in Japan based on a prospective multicenter database.

OBJECTIVES: To identify factors associated with prolonged length of stay (LOS) in spine surgery, with the goal of establishing details of LOS for multiple diseases and surgical procedures. PATIENTS AND METHODS: The subjects were patients who underwent spine surgery at 10 facilities in the Nagoya Spine Group from January 2005 to December 2015. Data were collected for patient background, primary spinal pathology, anatomical location of the lesion, and surgical methods. The primary outcome was LOS, which was defined as the calendar days from surgery to hospital discharge. RESULTS: A total of 10,829 patients (5953 males, 4876 females; age 5-93 years, mean 60.2 ± 28.8 years) were identified in the database. Average follow-up was 61 months (range: 13-120 months). Average LOS was 22.3 ± 21.3 days, and there was a gradual decrease in LOS over the study period. LOS was significantly correlated with age, and prolonged LOS was significantly associated with thoracic spine surgery and significantly longer after surgery with instrumentation. Average LOS was >30 days for intramedullary tumor resection and posterior cervical fusion, but only 10.2 days for microendoscopic discectomy. Reoperation was performed in 210 patients (1.9%) and these patients had a significantly higher average LOS of 43.1 days. CONCLUSION: These results will assist quality improvement in spine surgery. The identified risk factors for prolonged LOS will also assist in planning of surgery, postoperative care, and discharge, with the goal of reducing health care costs.

Serial evaluation of human anterior cruciate ligament grafts by contrast-enhanced magnetic resonance imaging: comparison of allografts and autografts.

PURPOSE: The purpose of this study was to clarify the difference in remodeling between allografts and autografts in anterior cruciate ligament reconstruction. METHODS: We examined 24 knees with bone-patellar tendon-bone allografts and 20 knees with central-third bone-patellar tendon-bone autografts. Surgical patients from January 1997 to December 2002 were included in the study, and more than 1 year had passed since surgery. The mean postoperative follow-up was 24.0 months in the allograft group and 21.3 months in the autograft group. Patients with a positive Lachman test were excluded. The operative method and postoperative rehabilitation programs were the same. All allografts were provided by Tokai Regional Bone Bank, the only regional bone bank in Japan. Contrast-enhanced magnetic resonance imaging (1.0 T, T1-weighted, sagittal section, infusion of 0.2-mL/kg gadolinium-diethylenetriamine pentaacetic acid [Gd-DTPA]) was performed for all knees at 1, 4, 6, and 12 months after surgery and performed for some knees irregularly thereafter. The signal/noise quotient (SNQ) of grafts was calculated by use of magnetic resonance imaging based on the method of Weiler et al. (2001) as follows: SNQ = (Signal of ACL graft - Signal of quadriceps tendon)/Signal of background. RESULTS: The SNQ of allografts was significantly lower than for autografts 12 months after surgery. As for the SNQ 1 month after surgery, there was no difference before or after Gd-DTPA infusion in the allografts; however, the SNQ was significantly higher after Gd-DTPA infusion in autografts. The SNQ after Gd-DTPA infusion continued to increase until 12 to 24 months in the allograft group but peaked at 4 or 6 months in the autograft group. CONCLUSIONS: Compared with autologous tendons, allogeneic tendons have a slower onset and rate of revascularization. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Postoperative Complications Associated With Spine Surgery in Patients Older Than 90 Years: A Multicenter Retrospective Study.

STUDY DESIGN: A review of a prospective database. OBJECTIVES: Surgery for elderly patients is increasing yearly due to aging of society and the desire for higher quality of life. The goal of the study was to examine perioperative complications in spine surgery in such patients. METHODS: A multicenter study of surgical details and perioperative complications was performed in 35 patients aged older than 90 years who underwent spinal surgery, based on a review of a prospective database. The frequency and severity of complications were assessed, and the effects of patient-specific and surgical factors were examined. Major complications were defined as those that were life threatening, required reoperation in the perioperative period or left a permanent injury. Ambulatory function before and after surgery was also analyzed. RESULTS: Perioperative complications occurred in 19 of the 35 cases (54%), and included 11 cases of postoperative delirium, most of which occurred after cervical spine surgery. There were 8 major complications (23%), including cerebral infarction (n = 3), coronary heart disease (n = 3), pulmonary embolism (n = 1), and angina (n = 1). Preoperative motor deficit, operative time, estimated blood loss, and instrumented fusion were significantly associated with major complications. An improved postoperative ambulatory status occurred in 61% of cases, with no change in 33%, and worsening in 2 cases (6%). CONCLUSIONS: Timing of surgery before paralysis progression and reduced surgical invasiveness are important considerations in treatment of the very elderly. Improved outcomes can be obtained with better management of spine surgery for patients aged 90 years or older.

[Oral osteoporosis: a review and its dental implications].

In post-menopausal osteoporosis, lack of estrogen will affect the remodeling of the bone tissue in such a way that, in most patients with periodontitis, the amount of bone resorbed exceeds that being formed, resulting in net bone loss. Osteoporosis can be treated by a variety of methods, the hormone replacement therapy (HRT), the selective estrogen receptor modulators (SERM) and the bisphosphonates. The HRT or bisphosphonates treatments improve the clinical outcome of periodontal disease and may be an adjunctive treatment to preserve periodontal bone mass. This paper reviews the current evidence on the mechanism of periodontal breakdown after menopause and the benefit to oral health by treatments for osteoporosis.

Salvage operation for persistent low back pain and sciatica induced by percutaneous laser disc decompression performed at outside institution: correlation of magnetic resonance imaging and intraoperative and pathological findings.

OBJECTIVE: We identified several problems associated with percutaneous lumbar disc decompression (PLDD) based on a study of patients who required salvage operations for complications after undergoing PLDD at an outside institution. BACKGROUND DATA: PLDD has been performed as a new treatment for intervertebral disc herniation in recent years, and its safety and effectiveness are in the process of being established. Because the procedure is simple to perform under local anesthesia, inappropriate irradiation and application to patients for whom it is not indicated have sometimes resulted in a poor outcome and serious complications. METHODS: The patients comprised 10 with lumbar disc herniation and three with lumbar spondylolisthesis. We analyzed the magnetic resonance (MR) imaging and operative findings as well as the pathological features of surgically obtained disc specimens and studied their relationships with the clinical outcomes of the operations. RESULTS: Initial examination of all patients at our hospital showed that PLDD had no effect on low back pain or sciatica. In patients who showed MR signal changes in the end-plate, the pathological examination revealed extensive necrosis of cartilage and bone. During salvage operations, severe adhesion of herniated masses to nerve roots was often observed, with carbonized disc tissue surrounding the nerve roots and might have their nerve root injured thermally. CONCLUSION: PLDD is associated with significant risk of disc, end-plate, and nerve root injuries, contrary to the general belief that the procedure is minimally invasive. Our findings highlight the need for careful diagnosis and sufficient technical skill when selecting PLDD as a treatment option.