摘要:

This study presents the time course of clinical and radiographic progression of symptomatic osteonecrosis of the femoral head and examines those characteristics which may be associated with more rapid progression. Clinical and radiographic progression occurred regardless of initial Ficat stage with some differences in the time course of progression. Radiographic progression was sensitive, but was less specific in predicting eventual clinical failure. Patients aged over 40 years with Ficat stage III hips progressed faster then did other patients with osteonecrosis. Hips with lesions occupying an area greater than 50% of the femoral head were uniformly associated with clinical failure. Clinical failure also correlated with the extent of collapse in Ficat stage III hips. In general, however, progression occurred relatively uniformly and suggested that symptomatic osteonecrosis of the femoral head is a progressive disease.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Recent advances in diagnostic imaging, especially in magnetic resonance imaging, have enabled early diagnosis of osteonecrosis, before radiographic changes and femoral head collapse. This is of clinical importance because it allows prompt institution of prophylactic treatment, thus improving the outcome. Although it is now recognized that the extent of the necrotic lesion is a significant factor in determining prognosis and treatment, most published reports on the treatment of this condition have not attempted to correlate outcome with lesion size. This report reviews the different imaging modalities available for the diagnosis and evaluation of osteonecrosis and summarizes their accuracy and clinical role. It describes different methods for staging avascular necrosis as well as techniques for estimating or measuring lesion size. The close correlation between lesion size and outcome is emphasized. These findings encourage the use of a method of evaluation and staging that includes a specific determination of lesion size as well as stage.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

In femoral head osteonecrosis, the processes of subchondral fracture and head collapse are mechanical events, and therefore are amenable to study using techniques of biomechanics, especially finite element analysis. Also, most interventions undertaken to forestall collapse attempt to do so by providing a mechanically more favorable environment for weakened areas of the head, and in many instances their structural efficacy can be quantified. This article reviews the literature on the biomechanics of osteonecrosis, focusing on how the lesion morphology influences collapse risk, and the degree to which surgical interventions serve to reduce that risk. Interventions considered include osteotomy, core drilling, and structural bone grafting.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

This communication presents the author's perspective on recent advances in the study of osteonecrosis, explores the controversies that have arisen in the literature relating to treatment alternatives, and suggests an approach to the use of core decompression in the early stages of osteonecrosis that can prove useful to the practicing orthopaedist. Currently available diagnostic measures can identify osteonecrosis at very early stages of femoral head involvement. Quantitation of femoral head involvement on magnetic resonance imaging can differentiate lesions by the volume of head involvement and the location of the involvement relative to the weight-bearing articular surface. Although it is not yet known whether lesion size determines the effectiveness of treatment with core decompression in disease that is not yet radiographically apparent, bigger lesions are likely to respond differently then small lesions. The author applies this rationale to stage I and early stage II disease, for which core decompression is the preferred treatment. Core decompression without supplementary steps does not appear adequate for larger stage II lesions or more advanced disease. A technique that is safe and predictable should provide proper placement of the core tract, biopsy of the lesional area (desirable), and is chosen for the appropriate patient. All willing patients should be encouraged to enter into randomized prospective treatment protocols.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Many patients have had excellent therapeutic results with core decompression for osteonecrosis of the femoral head. However, this experience has not been uniform and shows considerable variability in both clinical and radiographic results that have been reported. Additionally, it is now apparent that core decompression has minimal usefulness in Ficat III lesions presenting with or without collapse. A variety of techniques have been examined to reduce the variability and extent the range of core decompression. These techniques collectively seek to enhance bone formation and/or decrease bone resorption with the goal of maintaining structural integrity of the femoral head and preventing segmental collapse. This review describes some of these efforts with bone grafts, demineralized bone matrix, bone morphogenic proteins, and electric and electromagnetic fields. Our personal experience with demineralized bone matrix and electromagnetic stimulation is described. These techniques use core decompression as a portal to the necrotic zone in the femoral head for the introduction of materials, devices, and techniques by which bone formation may be stimulated.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

For the past 30 years, nonvascularized bone grafts have been used in the treatment of osteonecrosis of the femoral head. Originally, various tibial, fibular, or iliac crest grafts were introduced through a core track into the femoral head. These produced less than optimal long-term results. More recently, various grafts have been used through windows made in the femoral neck or head to more directly replace the dead bone and support the collapsing segment. Results of these recent techniques are promising and may be further improved in the future by pharmacologic agents that enhance bone healing.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Osteonecrosis of the femoral head is a debilitating disease that primarily affects the young adult. As total hip arthroplasty is undesirable in this population, many alternatives to femoral head salvage have been reported; unfortunately, these options have stimulated much controversy and results have been less than ideal. Free vascularized fibular grafting to the femoral head, however, has shown some success, with a survival of greater than 10 years in more than 80% of cases, particularly in hips without subchondral collapse. This procedure may also benefit young patients with more advanced osteonecrosis of the femoral head by halting progression of collapse, prolonging reduction of symptoms, and postponing total hip replacement. The authors' experience with free vascularized fibular grafting for the management of femoral head osteonecrosis is shared in detail, with an overview of indications, preoperative evaluation, surgical techniques, and postoperative care.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Intertrochanteric osteotomy has a limited but useful role in carefully selected cases of osteonecrosis with small-sized necrotic sectors. In fact, the size of the lesion is a major factor in results from all methods of treatment for osteonecrosis, other than hip arthroplasty. A staging system that incorporates the size of the necrotic sector, such as the Steinberg classification system, is extremely helpful in assessing the outcomes of clinical series. Even initially successful osteotomies most often ultimately require conversion to total hip arthroplasty for the majority of patients. The conversion rate to total hip is approximately 50% at 10 years post osteotomy. Therefore, it is important for surgeons to perform the osteotomy in a manner that facilitates subsequent total hip replacement.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The treatment of symptomatic osteonecrosis of the femoral head presents a challenge, particularly in young patients with significant femoral head deformity. Whereas retention of the femoral head is widely accepted as the goal of early treatment, attempts to reconstitute the femoral head are usually unsuccessful, and some form of replacement arthroplasty must be considered. When subchondral fracture and segmental collapse have occurred, especially if accompanied by degenerative changes in the acetabulum, hip reconstruction is usually recommended. Advanced stage avascular necrosis of the femoral head remains a particularly challenging disease to treat because it most commonly affects young, active patients in the third through fifth decades of life. Treatment of patients in this demographic is challenging in that a functional and durable hip operation is required. In the majority of patients requiring hip reconstruction, total hip replacement is the procedure of choice. Utilizing contemporary instrumentation and techniques, results in patients with osteonecrosis are becoming more predictable. Our efforts remain focused on improving the durability and long-term survivorship of total hip replacement. In this article we will review the information available on total hip arthroplasty and its various forms.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The choice of treatment for osteonecrosis of the femoral head should be based primarily on the stage of the lesion. Patient-related factors also influence treatment alternatives. The extent of an osteonecrotic lesion of the hip can be determined predominantly from radiographic findings. The authors primarily use four parameters: presence of collapse, lesion size, extent of head depression, and acetabular involvement. In smaller precollapse lesions, nonoperative pharmacologic methods and core decompression may do well. Bone grafting, both vascularized and nonvascularized, may have better results in larger precollapse and early postcollapse lesions. Limited femoral resurfacing has a role in postcollapse lesions in which the acetabular cartilage is preserved. Total hip arthroplasty is the only treatment for lesions with extensive acetabular involvement. A treatment algorithm is presented.

ISSN:0885-9698    

出版商:OVID    

年代:2001

数据来源: OVID