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Neil A Sharkey – One of the best experts on this subject based on the ideXlab platform.
biomechanical consequences of fracture and repair of the posterior wall of the AcetabulumJournal of Bone and Joint Surgery American Volume, 1995Co-Authors: Steven A Olson, Michael W Chapman, Neil A SharkeyAbstract:
We measured the distribution of contact area and pressure between the Acetabulum and the femoral head of cadaveric pelves in three different conditions : intact, with an operatively created fracture of the posterior wall, and after anatomical reduction and fixation of the fracture with a buttress plate and interfragmentary screws. The study involved eight cadaveric hip joints from five pelves loaded to 2000 newtons in simulated single-limb stance. Measurements were made with pressure-sensitive film. The Acetabulum was divided into three areas – the anterior wall, the superior aspect, and the posterior wall – for the analysis of the data. Creation of a fracture of the posterior wall was followed by an increase in contact area, maximum pressure, and contact force in the superior aspect of the Acetabulum. A concomitant decrease in these parameters was observed in the anterior and posterior walls. Anatomical reduction and fixation of the fracture with a plate and screws did not restore the pattern of loading to pre-injury levels. CLINICAL RELEVANCE : This study demonstrates the marked alteration in the mechanics of load transmission across the hip after a fracture of the posterior wall of the Acetabulum. These findings are consistent with the clinical observations of Rowe and Lowell that large fractures of the posterior wall of the Acetabulum that have been treated non-operatively predispose the hip joint to osteoarthrosis. The failure of acute anatomical reduction and internal fixation to restore normal joint-loading parameters supports the current clinical practice of restricting weight-bearing after operative repair of these fractures.
David L Helfet – One of the best experts on this subject based on the ideXlab platform.
a radiographic study of the ossification of the posterior wall of the Acetabulum implications for the diagnosis of pediatric and adolescent hip disordersJournal of Bone and Joint Surgery American Volume, 2013Co-Authors: Peter D Fabricant, Bryan T. Kelly, Brandon P Hirsch, Ian Holmes, Dean G Lorich, David L Helfet, Eric A Bogner, Daniel W GreenAbstract:
Background: Subtle variations in acetabular morphology have been implicated in several pathologic hip conditions. Although it is understood that the Acetabulum forms at the junction of the ilium, ischium, and pubis at the triradiate cartilage, the ossification and development pattern of the posterior wall of the Acetabulum is unknown. Standard radiographs and computed tomographic scans used in evaluation of the adolescent hip do not allow a complete assessment of the non-ossified portions of the developing Acetabulum. The purpose of this study was to define the currently unknown ossification pattern and development of the posterior wall of the Acetabulum and to determine when conventional imaging, with use of computed tomography and radiographs, is appropriate.
Methods: One hundred and eighty magnetic resonance imaging examinations in patients who were four to fifteen years old were evaluated by a musculoskeletal radiologist for ossification patterns of the posterior wall of the Acetabulum and triradiate cartilage. Correlations were made with available radiographs.
Results: Posterior acetabular wall ossification lags behind anterior wall ossification throughout development. On average, the posterior wall of the Acetabulum began to ossify at the chronological age of eight years, followed by a discrete rim of posterior calcification (posterior rim sign) at the patient age of twelve years, just prior to the fusion of the posterior acetabular wall elements to the pelvis. This preceded the closure of the triradiate cartilage in all subjects. On average, male patients had fusion of the posterior wall of the Acetabulum one to 1.5 years after female patients.
Conclusions: The ossification of the posterior wall of the Acetabulum is completed in a predictable manner prior to closure of the triradiate cartilage.
Clinical Relevance: Prior to closure of the triradiate cartilage (typically at the age of twelve years in girls and fourteen years in boys), magnetic resonance imaging, rather than radiographs and computed tomography, should be used to evaluate a child with hip pain or to measure and characterize acetabular morphology when cross-sectional imaging is indicated. This study characterizes a secondary ossification center along the edge of the posterior wall of the Acetabulum that becomes ossified just prior to fusion. This secondary rim ossification center should not be confused with pathologic conditions such as labral avulsion or posterior acetabular wall injury.
Periprosthetic fractures of the Acetabulum.Journal of Bone and Joint Surgery American Volume, 2004Co-Authors: David L Helfet, Arif AliAbstract:
Periprosthetic fractures of the Acetabulum after total hip arthroplasty are uncommon, but are increasing in number and severity. These fractures may occur intraoperatively, during the perioperative period, or many years after the total hip arthroplasty. Periprosthetic fractures of the Acetabulum vary in severity and may involve stress fractures of the pubis or medial wall, significant bone loss secondary to osteolysis and subsequent loss of column integrity, or complete pelvic discontinuity. Treatment differs depending on the complexity of the fracture and the stability of the acetabular prosthesis. Surgical treatment for an unstable Acetabulum should stabilize the bony columns of the Acetabulum, provide bone grafting of defects, and should maintain adequate bone stock for replacement of a stable acetabular implant. Strict adherence to the principles of fracture surgery is required to achieve bony union of the acetabular columns and provide a stable environment for reimplantation of an acetabular component.
mri assessment of the posterior acetabular wall fracture in traumatic dislocation of the hip in childrenPediatric Radiology, 2002Co-Authors: Ivan F Rubel, Peter Kloen, Hollis G Potter, David L HelfetAbstract:
Traumatic hip dislocations associated with posterior wall fractures of the Acetabulum in the pediatric population are in general a consequence of high-energy trauma. After expeditious reduction, instability mandates for further diagnosis and intervention. Plain radiographs or computerized tomography (CT) scans can misjudge the involvement of the posterior wall of the Acetabulum due to the partially calcified nature of the pediatric bone. We present two cases of pediatric traumatic hip dislocation associated with posterior wall fractures of the Acetabulum. In both cases, obvious postreduction instability was noted without conclusive findings of etiology on plain X-rays or CT scans. Magnetic resonance imaging (MRI) disclosed an extensive posterior wall traumatic involvement in both cases and helped to decide in favor of open reduction of the hip and internal fixation of the posterior wall fragment.
Pan Zhenhu – One of the best experts on this subject based on the ideXlab platform.
the treatment progress of the Acetabulum fracture involving posterior wallJournal of Liaoning Medical University, 2015Co-Authors: Pan ZhenhuAbstract:
Acetabulum fracture,the most common injury in the traumatic fractures,has been greatly increased. Currently,there are many materials for internal fixation of Acetabulum fracture involving post wall. In this study,the latest documents at home and abroad have been reviewed on the internal fixation of Acetabulum fracture involving post wall in the past several years. The main points include the merits and limitations for each kind of internal fixation and the comparison with each other as well. Meanwhile,the treating methods for fixation Acetabulum fracture involving post wall is prospected.