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Pedicle screw fixation is frequently used for spinal fusion in elderly patients. The application of pedicle screw fixation for elderly patients with degenerative lumbar disease remains controversial due to problems such as surgical invasion, osteoporosis, and cost performance. Outcomes of spinal fusion using pedicle screw fixation were evaluated in patients older than 70 years with lumbar spinal canal stenosis. Eighty-one patients older than 70 years with degenerative disorders of the lumbar spine were treated with pedicle screw fixation before 1997. They were 70 to 85 years at screw fixation (mean, 74.1 years). The postoperative follow-up period was 3 to 18 years (mean, 8.2 years). The number of fused levels by pedicle screw fixation was 1 to 7 (mean, 2.1), and bone grafting was performed in 19 patients who underwent posterolateral lumbar fusion with posterior lumbar interbody fusion and in 62 (76.5%) who underwent posterolateral lumbar fusion alone. Bone union was radiographically observed in 90.1%. The grade of independence (Independence [Bedridden] Criteria of the Daily Life of the Impaired Elderly) had been rank J (life independence) in all patients 1 year preoperatively, but deteriorated to rank A1 (capable of going out with a helper) in 51.8% of patients and rank B1 (using a wheelchair) in 19.8% immediately preoperatively. The grade of independence was rank J in 85.6% of patients 3 years postoperatively and remained rank J in 40 (87.0%) of the 46 who were alive 10 years postoperatively. Few complications associated with surgical invasion were found, and the grade of independence tended to remain at a high level for 10 years postoperatively. [ABSTRACT FROM AUTHOR]

In general, osteoporosis is evaluated using the bone mineral density (BMD) of the lumbar spine, which can be obtained from dual energy x-ray absorptiometry (DEXA) in lumbar spine radiographs. However, measurements are sometimes difficult in fracture cases, and corrections are necessary among measurement devices or different types of these devices. Furthermore, correlation coefficients vary at different measurement sites. In this study, we attempted to evaluate osteoporosis in tbe pedicle cortex in anteroposterior (AP) views of plain lumbar radiographs.The width of the cortical bone of tbe pedicle (distance between the external and internal margins of the cortical bone) and the cortical bone of the pedicle index in 190 women were determined using AP plain radiographs of the L2 and L3 pedicle, and their relationships with BMD were categorized and investigated by age and BMD (BMD was determined using DEXA).The measurement of the widtb of tbe cortical bone of the pedicle and the cortical bone of the pedicle index for L2 and L3 were found to be suitable for evaluation of the relationship between thickness of tbe cortex of pedicles and osteoporosis. The width of the cortical bone of the pedicle and the cortical bone of the pedicle index for L2 and L3 significantly decreased with age. Correlation coefficients of 0.589 and 0.601 were found between the width of the cortical bone of the pedicle and age and BMD, respectively. Using AP plain lumbar radiographs, the width of the cortical bone of the pedicle for L2 and L3 was determined and a correlation with BMD was obtained. Measurements of the width of the cortical bone of the pedicle may be useful for evaluation of degree of osteoporosis. [ABSTRACT FROM AUTHOR]

Patients with metastatic spinal tumors often experience paralysis caused by spinal cord compression. Several studies have investigated metastatic lesion-related spinal cord compression. This study is the first to examine the relationship between the epidural spinal cord compression (ESCC) scale, which measures circumferential compression, and the functional outcomes of treatment, which were assessed at regular intervals after treatment until death. A total of 191 patients who had grade D or worse paralysis on the American Spinal Injury Association (ASIA) classification scale and a grade 1b or more severe cord compression on the ESCC scale were included in the study. Patients had been treated with surgery combined with radiotherapy (n=146) or radiotherapy alone (n=45). Three spinal surgeons assessed the ESCC grade of for patient, and the grade agreed to by at least 2 surgeons was adopted. After 4 weeks, re-evaluations were conducted by the same examiners. The authors also calculated the mean kappa coefficients for inter- and intra-examiner variability (0.88 and 0.93, respectively). The distribution of the ASIA grade differed significantly among the ESCC scale grades (P=.0102). However, the degree of improvement in paralysis in terms of the ASIA grade (≥1 grade of improvement, no change, or ≥1 grade of aggravation) was not significantly associated with the ESCC grade (P=.2334). The ESCC scale was found to be a useful indicator of circumferential spinal cord compression but was not identified as a significant functional prognostic factor for paralysis. [Orthopedics. 2020;43(6):e567-e573.]., (Copyright 2020, SLACK Incorporated.)

Autologous bone grafting is an established method to overcome bone deficiencies in primary total knee arthroplasty (TKA). However, recently, metal augments have been used by many surgeons. Although autologous bone grafting is a common technique, few large studies have described its success in achieving bone union in primary TKA. The goal of this study was to evaluate primary TKA with autologous bone grafting for tibial defects. A total of 68 knees that had undergone arthroplasty with autologous bone grafting with more than 1 year of follow-up were evaluated. Average follow-up was 6.6 years (range, 1.2-14.6 years). The autologous bone grafting procedure attached the proximal portion of the tibial resection from the lateral side to the bone graft on the medial side with 2 screws. The prosthesis, which had a standard and nonrevision stem, was implanted with cement. Bone union was assessed with fluoroscopic radiography with a weight-bearing anteroposterior view. The rate of bone union was 97% (65 knees). Correction of preoperative alignment was achieved and maintained until final follow-up. Postoperative knee angle and knee and function scores showed significant improvement. One infection occurred, but there were no local complications, such as backout of screws or collapse of bone grafts. The authors believe that autologous bone graft within TKA is a relatively simple and effective procedure that provides good bone union. [Orthopedics. 2017; 40(4):e604-e608.]., (Copyright 2017, SLACK Incorporated.)

The goal of the study was to evaluate minimally invasive palliative surgery and the effect of postoperative adjuvant therapy for metastatic spinal tumor with a limited vital prognosis. Of the 70 patients who underwent palliative surgery for metastatic spinal tumor at the authors' hospital between March 2012 and May 2016, thirty-three were treated with minimally invasive spine stabilization (MISt) using percutaneous pedicle screws (PPSs) and included in the current study. Of the 33 patients, 26 were men and 7 were women; mean age at surgery was 68.6 years. Intraoperatively, posterior decompression and fusion was performed in 17 (51.5%) patients and fusion only was performed in 16 (48.5%). Mean operative time was 202.5 minutes, mean intraoperative blood loss was 331.6 mL, and intraoperative blood loss was 1500 mL or greater in 2 (6.1%) patients. Median postoperative survival time determined using the Kaplan-Meier method was 11.0 months (95% confidence interval, 7.3-14.6). Regarding improvement of paralysis, neurological deficit was improved by at least 1 Frankel grade for 15 (45.5%) patients, and the number of ambulatory patients increased from 22 (66.7%) to 25 (75.8%). Postoperative adjuvant therapy included chemotherapy in 17 (51.5%) patients, radiotherapy in 21 (63.6%), and bone-modifying agent treatment in 25 (75.8%). The mean Barthel Index for activities of daily living improved from 53.5 preoperatively to 71.5 postoperatively. Discharge to home was possible for 23 (69.7%) patients. Activities of daily living for patients with metastatic spinal tumor were improved by minimally invasive palliative surgery with MISt using PPSs and postoperative adjuvant therapy. [Orthopedics. 2017; 40(4):e693-e698.]., (Copyright 2017, SLACK Incorporated.)

Fondaparinux and enoxaparin are useful for preventing venous thromboembolism after total knee arthroplasty (TKA), but both drugs have associated complications. The purpose of this study was to clarify the risks associated with use of these drugs in Japanese patients who underwent TKA.A total of 575 patients (935 knees) underwent TKA and were retrospectively reviewed; 277 patients (454 knees) were treated with fondaparinux and 298 patients (481 knees) were treated with enoxaparin. The authors investigated the incidences of deep venous thrombosis of the lower limbs and pulmonary embolism to evaluate venous thromboembolism, knee enlargement compared with the preoperative size, incidence of subcutaneous knee hematoma, and other complications. No significant differences were observed between the 2 drugs regarding the incidences of deep venous thrombosis and pulmonary embolism. However, fondaparinux use resulted in knee enlargement (P<.0005) and subcutaneous hematoma of the knee (P=.035) significantly more often than enoxaparin use. Conversely, enoxaparin use significantly caused the elevation of alanine aminotransferase (one of the liver enzymes) at a higher rate than fondaparinux (30.1% vs 8.3%, respectively; P<.0001). However, the increased alanine aminotransferase levels were transient, and no patient exhibited symptoms of abnormal liver function, such as jaundice or cutaneous pruritus.Fondaparinux and enoxaparin were both effective in preventing venous thromboembolism in Japanese patients undergoing elective TKA. However, both drugs had some adverse effects. It is important to be aware of these potential risks when prescribing these drugs., (Copyright 2013, SLACK Incorporated.)

This article reports a case of bilateral fatigue fracture of the femoral components in a cruciate-retaining uncemented total knee arthroplasty (TKA). A 75-year-old woman (height, 158 cm; weight, 72 kg; body mass index, 29.2) had undergone one-stage bilateral TKA for osteoarthritis 11 years previously at the author's institution. Surgery was performed using an uncemented Flexible Nichidai Knee. Equal tension of the collateral ligaments and normal mechanical axis were achieved during the primary procedure. The patient was an ardent lover of the game of badminton and had higher activity levels with daily playing. At 8 years postoperatively, she started complaining of mild pain in both knees. The pain gradually increased, and at 11 years postoperatively, she had difficulty walking. Anteroposterior radiographs showed narrowing of the medial joint space, indicating wear of the polyethylene insert. Lateral radiographs showed signs of broken implants in both knees. There were no signs of gross implant loosening or osteolysis. One-stage revision surgery was performed, and the knees were converted to cemented posterior-stabilized TKAs. At revision, the bilateral femoral components were found to be fractured at the junction between the trochlear flange and the medial condyle, anteriorly to the medial peg. The polyethylene insert showed mild wear at the medial middle portion. In the majority of case reports, stress fractures of the femoral component have predominantly affected the medial condyle, following uncemented implantation of fixed-bearing knees. In this case, failure of bone ingrowth in uncemented components, higher body mass index, and a higher athletic activity led to fatigue fracture of the femoral components., (Copyright 2011, SLACK Incorporated.)

The goal of this study was to evaluate the long-term survivorship of primary cementless total hip arthroplasty (THA) using Harris-Galante porous I acetabular and Harris-Galante porous femoral components. From July 1985 to December 1991, we performed primary cementless THA on 76 hips (70 patients). Twenty-nine patients (31 hips) died due to causes unrelated to the THA, and 6 patients (7 hips) were lost to follow-up. Of 76 hips (70 patients) studied, 38 hips (35 patients) were available for follow-up at a mean 22.5 years (range, 19-25 years) postoperatively. Mean patient age at index procedure was 51.2 years (range, 42-65 years). Average Harris Hip Score was 40.5 points preoperatively and 85.8 points at final follow-up. No patient had an early or late postoperative deep infection. Radiographically, the acetabular component fixation was stable in all 38 hips. The femoral component was bone-ingrown in 26 hips, stable-fibrous in 10, and unstable in 2. One unstable hip required revision of the femoral component. Dissociation of the polyethylene liner occurred in 3 hips without fractures of the metal locking tines and required revision of the polyethylene liner and the articular head. A total of 4 hips had documented revision, and 1 femoral component failed radiographically. The survival rate with the endpoint defined as revision surgery and radiographic loosening was 86.8% at 22.5 years of follow-up. Mean polyethylene wear was 0.085 mm/year (range, 0.031-0.15 mm). This study found that the Harris-Galante porous I acetabular and Harris-Galante porous femoral components produce excellent long-term results., (Copyright 2011, SLACK Incorporated.)

We evaluated the fate of bulk femoral head autograft in cementless total hip arthroplasty (THA) for developmental hip dysplasia. Of 87 hips (80 patients) studied, 37 hips (32 patients) were available for follow-up at a mean of 18.5 years (range, 15-24 years) postoperatively. The mean age of these 32 patients at the index procedure was 53.8 years (range, 40-65 years). The initial diagnosis was osteoarthritis in all 32 patients. The degree of acetabular dysplasia according to Crowe classification was type I in 18 hips (48.6%), type II in 14 (37.8%), type III in 5 (13.5%). The mean percentage of horizontal coverage of the acetabular components with graft bone was 34% (range, 25%-45%). Trabecular bridging across the graft-host interface was seen at a mean of 4 months (range, 2-6 months) postoperatively. Trabecular reorientation of the grafted bone was seen in all hips at a mean of 27 months (range, 12-36 months) postoperatively. There was no evidence of collapse and bony resorption of the grafted bone in the weight-bearing portion. Acetabular component fixation was stable in all hips at final follow-up. Of the 37 hips (32 patients), 2 acetabular components required revision: 1 for a late postoperative deep infection and 1 for dissociation of the polyethylene liner. The survival rate was 94.5% (95% confidence interval, 91.3-96.5) for the acetabular component at 18.5 years of follow-up. This study found that bulk femoral head autograft in cementless THA for developmental hip dysplasia produces excellent long-term results., (Copyright 2011, SLACK Incorporated.)

This article presents a case of femoral corrective osteotomy for malunited supracondylar femoral fracture after total knee arthroplasty (TKA) in a patient with rheumatoid arthritis. The patient underwent 1-stage bilateral TKA and 2-stage bilateral total hip arthroplasty 17 years prior at our institution. Her fall 10 years before led to a supracondylar femoral fracture that was treated nonoperatively for 3 months and led to malunion. Complaints of mild right knee pain and remarkable varus deformity were observed. On examination, the right knee was not swollen and tender. Range of motion (ROM) of the right knee was 0° to 130°. The patient needed crutches to ambulate. Knee score and function scores, according to the Knee Society clinical rating system, were 65 and 25 points, respectively. Radiographs after malunion showed remarkable varus knee and the femorotibial angle was 197°. At the time of surgery, the components were stable and bone union was completed. Valgus corrective osteotomy of the femur was performed using a retrograde intramedullary nail, with satisfactory results at 10-year follow-up. The patient is able to walk without a cane and has 0° to 130° ROM. Knee and function scores were 88 and 80 points, respectively. Radiographs showed complete bone union and the femorotibial angle was 179° with no loosening of the prostheses. Femoral corrective osteotomy is recommended for malunited supracondylar femoral fracture after TKA., (Copyright 2010, SLACK Incorporated.)

We compared the results of 1-stage uncemented bilateral total hip arthroplasty (THA) performed in 49 patients (98 hips) with those of 2-stage uncemented bilateral THA performed during the same hospital stay in 40 patients (80 hips). There was no significant difference in mean Harris Hip Score preoperatively and at final follow-up between the 2 groups. Radiographic evaluation of patients in the 1-stage group revealed the acetabular component was stable in 95 hips and possibly unstable in 3. The femoral component was bone-ingrown in 91 hips and stable fibrous in 7. In the 2-stage group, the acetabular component was stable in 77 hips and possibly unstable in 3. The femoral component was bone-ingrown in 71 hips and stable fibrous in 9. In both groups, no patients exhibited clear signs of loosening, migration or osteolysis.In the 1-stage group, postoperative dislocation occurred in 2 hips and 1 patient had developed deep venous thrombosis and pulmonary embolism. In the 2-stage group, no complications were observed. The incidence of complications was not significantly different between the 2 groups.There was no significant difference in the total blood loss and mean hemoglobin level preoperatively and at discharge between the 2 groups. However, in the 1-stage group, operative time, intraoperative blood loss, procedure cost, and hospital stay were significantly reduced compared with the 2-stage group. Therefore, 1-stage bilateral THA is a safe and effective option for patients with significant arthritic disease of both hips., (Copyright 2010, SLACK Incorporated.)

We assessed 90 total hip arthroplasties (THAs) performed with the Metasul metal-on-metal hip system (Zimmer, Warsaw, Indiana); the patients were monitored for >10 years. The average Harris Hip Score of the patients was 40.5 points preoperatively and 85.8 points at final follow-up. No adverse reactions to the metal debris were observed in patients presenting with symptoms or phenomena such as unexplained pain, joint effusion, bursitis, or pseudotumor. Radiographically, the acetabular component fixation was stable in 86 hips, possibly unstable in 3 hips, and unstable in 1 hip. The unstable hip required revision of the acetabular component. The femoral component was bone-ingrown in 81 hips and stable-fibrous in 9 hips. Distal femoral cortical hypertrophy was seen in 34.4% of hips.Postoperatively, 6 hips dislocated, of which 2 developed recurrent dislocation and required revision of the acetabular component. Dissociation of the polyethylene liner occurred in 2 hips 6 and 12 years postoperatively, respectively, and required revision of the polyethylene liner and the articular head. The survival rate with the endpoint defined as revision surgery and radiologic loosening was 94.4% at mean follow-up (12.3 years). This study found that the Metasul metal-on-metal THA produces excellent long-term results., (Copyright 2010, SLACK Incorporated.)

Vertebroplasty was performed using hydroxyapatite blocks to examine the course of compressive strength and histological features in a dog model. The vertebral fracture model was prepared by punching a hole in the center of the vertebra and at 4 sites around the vertebra (5 holes in total) from the front side of the vertebra using an air drill and hollowing the holes. Measurements were made on healthy vertebrae, vertebrae from the vertebral fracture model, vertebrae removed from animals immediately after vertebroplasty, vertebrae collected 1 and 2 months after vertebroplasty, and vertebrae untreated for 1 month after vertebral fracture. Histological examinations were also performed 1 and 2 weeks and 1 and 2 months after vertebroplasty with hydroxyapatite blocks. The strength of vertebrae in the fracture model immediately after vertebroplasty was significantly higher than that in the untreated fracture, and the strength of vertebrae 1 month after the procedure was equivalent to that of healthy vertebrae. Histologically, new bone formation was found around hydroxyapatite blocks 2 weeks after the procedure, and strong crosslinking between neighboring hydroxyapatite blocks was found after 1 month.These results suggest that hydroxyapatite blocks may be effective as filling material for vertebral fracture from both biomechanical and histological perspectives., (Copyright 2010, SLACK Incorporated.)

Many epidemiological surveys have identified smoking as a risk factor for osteoporosis, but it is unclear whether smoking has a direct effect on bone metabolism and if such an effect could cause osteoporosis. Therefore, we examined whether smoking causes osteoporosis based on the impact of smoke exposure on the bones of rats. A rat model of passive cigarette smoking was prepared by breeding rats in a cigarette-smoking box for 4 or 8 weeks. Histological changes, micro-computed tomographic (CT) analysis, mechanical bone strength, and bone mineral density of the femur and lumbar vertebrae were examined in these rats and in control rats that were not exposed to smoke. Lower mechanical bone strength was observed in smoke-exposed rats, but these differences were not significant. Significantly lower bone mineral density was found in the femur (P<.01) and lumbar bones (P<.001) of 8-week smoke-exposed rats compared to controls. In a micro-CT scan of lumbar vertebrae, the bone volume, trabecular thickness, trabecular number, and trabecular separation differed significantly between smoke-exposed rats and controls. Histologically, the osteocytes in the smoke-exposed rats were small (approximately 25% of the size in controls), and decreased numbers of marrow cells and osteoblasts (P<.01), as well as a black carbon dust-like substance, were found in the bone of smoke-exposed rats. These results indicate that smoking significantly decreases bone mineral density, which causes osteoporosis, and the organizational changes in the bone suggest a direct effect of smoking on bone structure. Fewer marrow cells were present in the smoke-exposed rats, and a black carbon dust-like substance was observed., (Copyright 2010, SLACK Incorporated.)

Posterior lumbar interbody fusion is considered to be an excellent fusion procedure to stabilize anterior support, correct alignment in the sagittal and coronal plane, and achieve foraminal decompression by lifting the disk height. The metal interbody cage in posterior lumbar interbody fusion is thought to be useful to prevent collapse of the graft bone and to correct and maintain disk height; however, some studies have noted a gradual decrease of disk height due to cage subsidence. Therefore, to investigate the significance of cage subsidence, 86 disk levels radiographically confirmed to have good union in 66 patients with posterior lumbar interbody fusion combined with pedicle screw fixation and a single metal cage for degenerative lumbar disease were retrospectively evaluated. The follow-up period ranged from 3 years to 10 years 3 months, with a mean of 7 years 9 months. Cage subsidence often showed a gradual increase over time. At final follow-up, subsidence averaged 4.0 mm on the cranial surface and 2.7 mm on the caudal surface. Although the average increase of disk height was 3.2 mm immediately postoperatively, the final disk height decreased by 4.2 mm on average from that time. The degree of cage subsidence and decrease of disk height were not correlated with the final clinical results. Subsidence was not correlated with bone mineral density in the vertebral body, body weight, or site of the insertion. On the other hand, the wedge shape of the cage and the thickness of the resected endplate had a significant influence on cage subsidence.

While various surgical procedures have been developed for the treatment of atlantoaxial subluxation due to rheumatoid arthritis, C1-C2 intra-articular screw fixation was developed to reduce intraoperative injuries to vertebral arteries. The purpose of this study was to report the therapeutic outcome of this procedure, which was followed for >2 years. Preoperative symptoms were alleviated in all patients. Only 1 patient with subaxial canal stenosis underwent additional laminoplasty during follow-up. All patients with class IIIA or milder neural deficit according to Ranawat's classification showed improvement to class I or II. There were no surgery-related complications or incidents, including injuries to vertebral arteries. Bone union was observed in all patients. No change was observed in the reduced atlas-dens interval during follow-up. The atlantoaxial angle was -6 degrees to 30 degrees (average, 19.4 degrees) at follow-up, and was >or=30 degrees after surgery (fusion in an overextended position) in only 1 patient. Although postoperative deterioration of cervical alignment was observed in 4 patients (18.2%), there was no additional surgery due to deterioration of cervical alignment. With no surgery-related complications or incidents, this procedure could be a safe and acceptable option for atlantoaxial subluxation due to rheumatoid arthritis.

There have been few reports on the imaging diagnosis and treatment of infection of interbody cages used in posterior lumbar interbody fusion. Even in a patient undergoing posterior lumbar interbody fusion using a metal cage, magnetic resonance imaging (MRI) might be able to diagnose epidural abscesses and diskitis when titanium alloy implants are used. When infection of the instrumented cage is diagnosed, emergency debridement with or without removal of implants, including the cage, appropriate wound closure, and the administration of potent antibiotics is the standard treatment. This article describes the conservative follow-up of a patient with epidural abscess and diskitis following instrumented posterior lumbar interbody fusion using a metal cage without surgical intervention. A 40-year-old man had undergone instrumented posterior lumbar interbody fusion at the L5/S1 level approximately 1 year previously. He suddenly developed a fever (temperature, 38 degrees C) and severe lower back pain without apparent cause. Late infection was suspected from his symptoms and laboratory findings, and a wide spectrum antibiotic was administered. On MRI, the low and high signal areas near the end-plate of L5/S1 were detected by T1- and T2-weighted imaging, respectively, and an abscess was noted around the cage. We recommended debridement as treatment; however, he refused further surgical intervention by reason of symptomatic remission. Therefore, wide spectrum antibiotics were continued. Fortunately, no lower back pain has recurred. Examination by MRI during the clinical course clarified the presence and disappearance of an epidural abscess and diskitis. Although the outcome of this case was fortunate, this conservative treatment is unusual, and is not recommended as standard treatment.