The "challenging" fractures of the odontoid process: a review of the classification schemes.

Fractures of the odontoid process seem to have an unclear and not well-understood behavior. This is well demonstrated in the literature as there is a disagreement in many fields, including the patterns of fractures, the percentage of pseudarthrosis or the appropriate treatment that is required. This situation makes the fracture itself a "challenging" one. Indeed, despite the existence of extensive literature, there are still many unresolved problems concerning these fractures. We recognize six main classification schemes of the odontoid process fractures which clearly demonstrate the presence of differences but, also, the disadvantages that these classifications are related to. The most important factors that render these fractures "enigmatic" are the anatomy of the odontoid, the diversity of fractures encountered, the radiological evaluation, the stability and the inability to incorporate the whole spectrum of fractures in one classification. The progress made the last decades in the field of the radiology and their follow-up permitted to better analyze these lesions and to extract useful conclusions.

Donor's site evaluation after restoration with autografts or synthetic plugs in rabbits.

AIM: To investigate donor site's area histological and immunohistochemical knee cartilage appearances after resurfacing iatrogenic defects with biosynthetic plugs orautografts. METHODS: Thirty New Zealand White rabbits were used in this study. A full-thickness cylindrical defect of 4.5 mm (diameter) × 7 mm (depth) was created with a hand drill in the femoral groove of every animal. In Group A (n = 10) the defect of the donor site was repaired with a biosynthetic osteochondral plug, in Group B (n = 10) with an osteochondral autograft, while in Group C (control group of 10) rabbits were left untreated. RESULTS: Twenty-four weeks postoperatively, smooth articular cartilage was found macroscopically in some trocleas' surfaces; in all others, an articular surface with discontinuities was observed. Twenty-eight out of 30 animals were found with predominantly viable chondrocytes leaving the remaining two -which were found only in the control group- with partially viable chondrocytes. However, histology revealed many statistical differences between the groups as far as the International Cartilage Repair Society (ICRS) categories are concerned. Immunofluoresence also revealed the presence of collagen II in all specimens of Group B, whereas in Group A collagen II was found in less specimens. In Group C collagen IIwas not found. CONCLUSION: The matrix, cell distribution, subchondral bone and cartilage mineralization ICRS categories showed statistically differences between the three groups. Group A was second, while group B received the best scores; the control group got the worst ICRS scores in these categories. So, the donor site area, when repairing osteochondral lesions with autografting systems, is better amended with osteochondral autograft rather than bone graft substitute implant.

Confronting hip resurfacing and big femoral head replacement gait analysis.

Improved hip kinematics and bone preservation have been reported after resurfacing total hip replacement (THRS). On the other hand, hip kinematics with standard total hip replacement (THR) is optimized with large diameter femoral heads (BFH-THR). The purpose of this study is to evaluate the functional outcomes of THRS and BFH-THR and correlate these results to bone preservation or the large femoral heads. Thirty-one patients were included in the study. Gait speed, postural balance, proprioception and overall performance. Our results demonstrated a non-statistically significant improvement in gait, postural balance and proprioception in the THRS confronting to BFH-THR group. THRS provide identical outcomes to traditional BFH-THR. The THRS choice as bone preserving procedure in younger patients is still to be evaluated.

Serum kinetics of soluble triggering receptor expressed on myeloid cells-1 differs in relation to the type of arthroplasty.

CONTEXT: Soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) participates in the inflammatory process. PURPOSE: To describe changes of sTREM-1 in the serum after hemiarthroplasty (HA) and total hip arthroplasty (THA). METHODS: Serial blood samples were drawn from 122 patients with hip fracture. Interleukin-6 (IL-6), sTREM-1, and C-reactive protein (CRP) were measured. RESULTS: IL-6 and CRP were similarly increased after both HA and THA. sTREM-1 was increased early in HA and late after THA. The only parameter that was higher among patients who developed systemic inflammatory response syndrome was IL-6. CONCLUSIONS: Kinetics of sTREM-1 differs among patients undergoing HA of the hip and those undergoing THA.

Increased expression levels of apolipoprotein J/clusterin during primary osteoarthritis.

Osteoarthritis (OA) is a slowly progressive degenerative joint disease that is associated with joint space narrowing, osteophyte formation and subchondral sclerosis. Despite extensive effort actual breakthroughs in the field of genetic or biochemical biomarkers of OA are limited. As secretory apolipoprotein J/clusterin (sCLU) has been implicated in both inflammatory and apoptotic molecular processes which contribute to the OA phenotype, the sCLU concentration in human serum and synovial fluid during advanced primary knee and hip OA was analysed. Elevated sCLU protein levels were shown in these two biological fluids. sCLU mRNA expression was also studied in normal cartilage and in advanced primary knee and hip OA samples. A significant up-regulation of sCLU mRNA expression (~25-fold) was found in samples collected from the tibial bone that was osteotomized during total knee arthroplasty in patients with primary knee OA, as compared to healthy tissue samples collected from the femoral head of macroscopically normal cartilage during the surgical treatment of subcapital fractures. By studying sCLU mRNA expression levels in samples collected during total hip arthroplasty in patients with advanced primary hip OA, an additional up-regulation of the sCLU mRNA expression (~4-fold), as compared to advanced primary knee OA, was found. Taken together, these observations indicate that the sCLU protein or mRNA expression level may be of a significant diagnostic and/or prognostic value during OA progression.

Routine needle biopsy during vertebral augmentation procedures. Is it necessary?

Vertebral augmentation procedures are currently widely performed to treat vertebral compression fractures. The purpose of this study was to determine the frequency of underlying previously unrecognized etiology in a consecutive series of patients undergoing kyphoplasty to treat vertebral compression fractures. A prospective histological evaluation of vertebral body biopsy specimens from presumed osteoporotic vertebral compression fractures were performed in order to identify aforementioned causes. Over a 2-year period, vertebral body biopsies from 154 vertebral levels were performed in 75 patients undergoing kyphoplasty for vertebral compression fractures. All patients received a preoperative workup that included plain radiographs, MRI, whole body bone scan, and laboratory examinations. Bone specimens were obtained from affected vertebral bodies and submitted for histologic evaluation to identify the prevalence of an underlying cause. All specimens demonstrated fragmented bone with variable amounts of unmineralised bone, signs of bone-remodeling and/or fracture-healing. In 11 patients underlying pathology other than osteoporosis was identified (prostate cancer, 1; pancreatic cancer, 1; colon cancer, 1; breast cancer, 2; multiple myeloma, 3; leukemia, 1; and lung cancer, 2). In all but one patient the results of the biopsy confirmed the diagnosis suspected from the preoperative workup. For the last patient, namely the one with pancreatic cancer, the workup did not identify the origin of the primary tumor, although the patient was considered to have a compression fracture secondary to metastatic disease of unknown origin, the vertebral biopsy suggested the presence of adenocarcinoma which eventually was proven to be pancreatic cancer. In augmentation procedures for vertebral compression fractures, bone biopsy should be reserved for the patients where the preoperative evaluation raises the suspicion of a non-osteoporotic etiology.

Cement leakage in a symptomatic vertebral hemangioma: a case report and review of the literature.

We present the case of a 50-year-old male with consistent back pain, not resolving with conservative treatment. Plain radiograms demonstrated a lytic lesion at the level of the 8(th) thoracic vertebra. Thorough examination with computerized tomography and magnetic resonance imaging revealed a hemangioma extending to the posterior third of the vertebral body, compressing the spinal cord at the level of 8(th) thoracic vertebra. A percutaneous vertebroplasty was performed. The post-operative computerized tomography scan demonstrated cement leakage. After thorough cement removal combined with extensive decompression and posterior stabilization, the patient reported gradual improvement of his symptoms and was able to return successfully to his work a few months later.

The effectiveness of two COX-2 inhibitors in the prophylaxis against heterotopic new bone formation: an experimental study in rabbits.

The purpose of this study was to present the effectiveness of 2 cyclooxygenase-2 inhibitors, meloxicam and parecoxib, in the prevention of heterotopic ossification. Eighteen white mature male rabbits were divided into 3 groups of 6 animals. One was the control group; 1 group was administered meloxicam subcutaneously, and 1 group was administered parecoxib subcutaneously. For the induction of heterotopic new bone, the Michelsson model was used. The extent of heterotopic new bone development was assessed according to Scott's classification. The meloxicam and parecoxib groups developed significantly less heterotopic bone when compared to the control group. There was no significant difference between the meloxicam and parecoxib group. We concluded that meloxicam and parecoxib are capable of preventing the development of heterotopic new bone in rabbits. The clinical relevance of this study is that meloxicam and parecoxib may be helpful in reducing heterotopic ossification in humans.

Isolated dislocation of the scaphoid.

Isolated dislocation of the carpal scaphoid is an extremely rare injury. The authors report herein a case of a 28-year-old man managed with open reduction and Kirschner wire fixation. The aim of this study is to comprehensively present this unusual injury along with its treatment and to attempt to merge the available experience in the literature in a suggested algorithm that will guide the surgeon confronted with this rare problem to treat it promptly and effectively.

Fixation of proximal humerus fractures using the PHILOS plate: early experience.

UNLABELLED: Proximal humeral fractures, especially in elderly patients, remain a challenging problem for the surgeon because the complication rate for these fractures still remains high. The internal locked system (PHILOS) plate is a new device used for proximal humerus fracture fixation is designed to decrease the high complication rate. We prospectively evaluated our early experience using this system. Twenty patients with fractures of the proximal humerus were treated with a PHILOS plate from September 2001 to January 2004 at Princess Alexandra Hospital in Harlow, UK. Functional assessment was done using the Constant shoulder score. Two patients who had brachial plexus injury were evaluated only with the visual analogue score because we thought that the Constant objective assessment would be unreliable. Complications were monitored. The mean Constant score was found to be 76.1% (range, 30-100%). The preliminary results seem to be satisfactory. According to our experience, the plate design provides stable fixation with a good functional outcome and eliminates most hardware problems such as failure and impingement syndrome. The PHILOS plate is suitable for the majority of fractures providing that the correct surgical technique is used. LEVEL OF EVIDENCE: Therapeutic study, level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Reaming versus broaching in cemented hip arthroplasty: mechanical stability in cadaver femora.

INTRODUCTION: We used an experimental hip model to assess the mechanical stability of a hip prosthesis, and compared the femoral medullary canal preparation techniques of reaming and broaching. METHODS: 15 pairs of cadaveric femora had a simulated replacement, the right femur with a reaming technique and the left with a broaching technique. Both femurs were radiographed to assess component positioning and cement mantle. The femurs were osteotomized 30 days after the procedure. The shear strength of the interface was studied at 4 different levels along an aluminum rod during push-out tests. RESULTS: The overall mean value of the interface failure load was 15% lower with the reaming technique (6.5 kN for the reaming technique versus 7.7 kN for the broaching technique; p = 0.02). INTERPRETATION: Broaching was superior to reaming for the preparation of the femoral canal, and should be used in order to increase primary stability. Further in vivo studies are required to account for factors such as intramedullary pressure, bleeding and surgical variations, which could not be accounted for in our study.

Distal intramedullary nail interlocking: the flag and grid technique.

Distal interlocking in intramedullary nailing of long bone fractures accounts for a significant proportion of the total fluoroscopy and operative time. We describe a modification of the "perfect circles" freehand technique employing a metallic grid temporarily attached to the skin of the lateral surface of the femur or to the medial surface of the tibia that acts as a fixed "navigational" aid. The position of the distal nail holes in relation to the grid is fluoroscopically ascertained. Subsequently, under fluoroscopic control, a modified Steinmann pin with a metallic handle attached to its blunt end ("flag") is used to accomplish targeting and to create the screw holes, affording improved visualization. This technique was compared with the traditional freehand technique in 2 groups of patients. Use of the modified technique led to reduction of radiation exposure and total distal interlocking time, and there were no significant complications related to the technique.

Revision anterior cruciate ligament surgery using the over-the-top femoral route.

Primary anterior cruciate ligament (ACL) reconstruction is considered a successful surgical procedure, but the results reported for revision ACL surgery are less satisfactory. The most common cause of technical failure in primary reconstruction is tunnel misplacement, particularly on the femoral side, although an anterior placement of the tibial tunnel may lead to graft impingement and failure. Several technical problems are encountered during revision procedures. We describe a technique for revision ACL surgery using a special jig for preparing the tibial tunnel that references the apex and roof of the intercondylar notch and an over-the-top routing for proximal femoral placement. This combination avoids graft impingement at the tibial tunnel exit and circumvents the problems associated with further femoral tunnel preparation.

Structural properties of the axis studied in cadaveric specimens.

Peripheral quantitative computed tomography scans of the axis in 20 fresh cadaveric specimens obtained at autopsy were studied to investigate the internal structural properties of the axis. In all specimens, serial scans were done in three planes. The area of the dens consisted of dense cortical and trabecular bone (Region 1, above the base of the dens) and showed statistically significantly greater peripheral quantitative computed tomography values when compared with the anterior part of the body of the axis (Region 2, below the base of the dens). An age-related progressive decrease of peripheral quantitative computed tomography values was observed, with specimens from subjects younger than 40 years showing statistically significantly greater peripheral quantitative computed tomography values when compared with those from subjects older than 40 years. A small area of trabecular bone with decreased density was found close to the anteroinferior edge of the body of the axis in the specimens from younger subjects. In contrast, a large area of trabecular bone with decreased density extending anteroinferiorly to superoposteriorly to the base of the dens was found in the specimens from older subjects. Based on these findings, we think that dens fracture classification systems and fixation techniques should be reconsidered.

Bone density study at the distal radius, using pQCT analysis, in Greek thalassemic patients.

BACKGROUND: Expansion of marrow spaces in thalassemia patients contributes to reduced bone density and increased risk of fractures. Peripheral quantitative computed tomography (pQCT) measures the volumetric bone mineral density (vBMD) independently in different compartments. OBJECTIVE AND METHODS: To study the regional bone structure in thalassemia, we performed pQCT (XCT-2000 Scanner, Stratec Inc.) in 57 young adult patients with beta-thalassemia major, aged 21-44 years (32 females). The vBMDs (total, trabecular, cortical + subcortical), Stress-Strain Index (SSI) and the cross-sectional area (CSA) were determined at the "4% site" of the distal radius; data were compared to reference values. RESULTS: Total vBMD, trabecular, cortical plus subcortical vBMD in thalassemics were significantly lower than in healthy adults (p<0.005). Thalassemic males had significant higher values of vBMD, SSI and CSA than females (p<0.005). CONCLUSIONS: In Greek thalassemic patients a significant reduction in bone density, associated with increased morbidity and risk of fractures, has been detected on pQCT examination.

Multiple level noncontiguous fractures of the spine.

From 1970 to 2000, 81 patients with noncontiguous fractures of the spine were evaluated. Of these 81 patients, 36 had a neurologic deficit. Sixty-six patients with stable injuries were treated conservatively, whereas 15 patients with unstable injuries required surgical stabilization. There was no neurologic deterioration either in the patients who had surgical stabilization or in the patients who were treated conservatively. Thirteen patients with an A score on the American Spinal Injury Association neurologic impairment scale did not improve and had a high mortality rate (61.5%). Although multiple level noncontiguous fractures of the spine are uncommon, they constitute a threat to neurologic function, and therefore warrant radiographic evaluation of the entire spine with multiple injuries.