Background

Conflicting results about the impact of blood transfusions on outcomes after total knee arthroplasty (TKA) have been reported. We hypothesized that transfusions would be associated with greater readmission and complication rates after primary TKA.

Introduction: Cementless total hip arthroplasty has been advocated for osteonecrosis of the femoral head (ONFH) as these patients are generally younger and more active than patients with osteoarthritis (OA). Since introduced in the early 1980’s, there have been several generations of cementless total hip prostheses. This study examined the outcome of the femoral stem of four generations of uncemented total hip prostheses.

Materials and Methods: One hundred and fifty-eight hips in 135 osteonecrosis patients (71 men, 64 women) who had a mean age of 46 years (range, 17 to 83) were included. The total number of prostheses included: PCA™ (77), E Series™ (47), Meridian™ (18), and Citation™ (16) (all Stryker, Mahwah, New Jersey). The mean follow-up was 105.5 +/− 60.8 months (range, 20 to 257 months). As part of an ongoing IRB-approved study, data collected includes Harris Hip (HHS) and QOL scores, re-operations (including revisions), and complications.

Results: The femoral components of 142 cases were not revised. These patients had a mean HHS of 86.3 +/− 13.2 points. Of the 15 revisions (9.6%), the primary reasons were loosening and/or significant osteolysis, but there was one infection and one chronic dislocation. The revisions included 10 PCA™ (13.0%) with a mean time to revision of 85 months (range, 25 to 132); 2 E Series™ (4.3%) with a mean time to revision of 85 months (2 cases in one patient; 68 and 101 months); 2 Meridian™ (11.1%) with a mean time to revision of 193 months (2 cases; 98 and 107 months); and 1 Citation™ (6.3%) with a time to revision of 30 months. The pooled revision rate of the 2^nd, 3rd, and 4^th generation was 5 of 80 (6.3%).

Discussion: There were no significant difference in revision rates between the different generations of uncemented femoral components (Chi Square, p=.433). However, the revision rates for the later generations were lower than the earlier generations.

There is a paradox surrounding the use of bisphosphonates and bone biology. On one hand, it has been used to treat osteoporosis, osteogenesis imperfecta, Pagets disease, osteonecrosis, and other disorders associated with low bone mass. On the other hand, there have been a number of cases reported suggesting an association between treatment with bisphosphonates and osteonecrosis of the jaw. Answers to why this paradox exists lies in a better understanding of the pathogenesis of osteonecrosis and the mechanism of action of bisphosphonates. This seminar was created to explore the perspectives of three different medical disciplines concerning the use of bisphosphonates.

Introduction: In the evaluation of various treatments that may have an effect on bone, there are certain inherent difficulties in selecting an appropriate outcome measure to determine whether a specific treatment is efficacious. This is particularly true for clinical studies.

Methods: Using Pubmed, a service of the U.S. National Library of Medicine that searches MEDLINE and other life science journals for citations of biomedical articles, a review of the current instruments used for outcome measures relating to osteonecrosis and bone blood flow was conducted. Abstracts from previous ARCO meetings were also reviewed.

Results: For the treatment of osteonecrosis, most outcome measures have focused on pain relief, surgery or need for surgery, disease progression (advancing stage), and change in lesion size. The first three options may be influenced by investigator bias and knowledge/experience. The last option may also be influenced by the technique used.

Imaging techniques continue to gain in sophistication. Gd-enhanced MRI can be used to assess perfusion of the diseased tissue. Doppler ultrasonography has also been used to estimate blood flow noninvasively. Near Infrared Spectroscopy (NIRS) can be used to measure tissue oxygenation.

While there has been recent interest in using biomarkers or genetic markers in the diagnosis and analysis of disease progression, more research is needed to determine the sensitivity and specificity of these techniques with respect to osteonecrosis.

Conclusion: Although there are a number of tests that can be used to evaluate the effect of a specific treatment on osteonecrosis, the definitive assessment will likely remain whether the disease progresses to the point that major surgery (resurfacing, vascularized fibular grafting, total joint replacement, e.g.) is required to relieve pain and restore function.

Introduction: Evidence-based medicine is a form of practice in which the physician accesses relevant, state-of-the-art research findings to guide the care of the individual patient (Gordon and Cameron, 2000). Therefore, evidence-based medicine should influence the decision making process when developing a treatment algorithm for early stage osteonecrosis. It was the purpose of this project to explore the literature concerning surgical options that are used currently to treat early stage osteonecrosis.

Materials and Methods: Literature searches were conducted using PubMed (National Library of Medicine, USA) to identify journal articles pertaining to the treatment of pre-arthrosis osteonecrosis during the past decade. The articles were screened to include only those with greater than 5 patients and greater than two year follow-up.

Results: Published reports in medical journals included: core decompression with and without nonvascular grafting (18); core decompression augmented with BMP or bone marrow cells (2); bone cement (1); vascularized graft – fibular or iliac (10); osteotomy (26); osteotomy and vascularized grafts (3); trap-door procedure (2); and hemiarthroplasty/resurfacing arthroplasty (9). There was one review of nonoperative treatment, but no clinical studies. There were only a few case reports concerning osteochondral graft/osteochondroplasty; which did not meet the inclusion criteria. Several classification systems were used: Ficat and Arlet (55%); University of Pennsylvania / Steinberg (21%); Japanese Investigational Committee (13%); Marcus (2%); Myers (3%); ARCO (5%), and other (1%). A majority of reports included follow-up of 5 years or greater (91%). Most studies (91%) were not randomized, control-matched, or prospective.

Discussion: Several surgical options are available for the treatment of pre-arthrosis osteonecrosis. However, it is not possible to apply evidence-based medicine practices to the research relating to the treatment of osteonecrosis as most of the research is not controlled and not comparative. This represents a substantial void in our knowledge base concerning osteonecrosis which remains to be filled.

Introduction: In a previous study (ARCO, 2002), we reported that the clinical results of revision total hip arthroplasty for osteonecrosis patients were less satisfactory than those found for a matched group of osteoarthritis patients. The aim of this study was to evaluate the potential factors that may have contributed to these findings.

Materials and Methods: This study included 34 hips in 30 osteonecrosis patients who had undergone revision of a femoral total hip arthroplasty component. There were 19 men (22 hips) and 11 women (12 hips) who had a mean age of 46.1 years (range, 28 to 69 years). The surgeries were performed between March 1984 and January 2001. Most femoral stems (91%) were implanted without cement. Prostheses were of different stem lengths, but most (97%) were proximally porous-coated. The mean follow-up was 8.2 years [range, 0.1 (a re-revision) to 19.8 years]. A physical examination as well as patient and physician outcome forms were collected at each visit. Preoperative x-rays were categorized according to the technique of Della Valle and Paprosky. A Kaplan-Meier survival analysis was performed (PEPI statistical software package).

Results: Risk factors for osteonecrosis included 15 corticosteroid, 8 alcohol, 7 trauma, and 4 unknown. This was the first revision in 27 cases, second revision in 5 cases, and third revision in 2 cases. Preoperatively, the defects included 4 Type I, 9 Type II, 15 Type IIIA, 2 Type IIIB, 1 Type IV, and 3 unknown types. Of the 34 hips, the femoral component was re-revised in 12 cases. One of the failures was the only fully porous coated stem that was implanted. One of the 3 cemented implants failed, as compared to 11 of the 31 implanted without cement. Survival rates were 90.9% (74.4%–97.1%) at 5 years, 54.8% (24.9%–81.6%) at 10 years, 54.8% (19.9%–85.6%) at 15 years, and 27.4% (1.7%–88.9%) at 20 years. There was no relationship between frequency of re-revision and defect category, risk factors, or age.

Discussion: Although there was a high failure rate (12/34; 34%) in this patient cohort, over 50% survived at least 10–15 years. The lack of a relationship between the patient age or the extent of defect and re-revision suggest that other factors concerning this disease need to be examined.