Introduction: Osteonecrosis is a devastating disease which can affect multiple joints including the distal radius. Although there are a number of studies that have reported the clinical outcomes of patients treated for osteonecrosis of the hip, knee, shoulder, and other locations, there are no known studies that have evaluated the outcome of patients who have this disease in the distal radius. The purpose of this study was to assess the characteristics of atraumatic, symptomatic osteonecrosis of the distal radius. In addition, based on reports that have shown the safe and effective use of core decompressions to treat early stages of osteonecrosis in other joints, we assessed whether this treatment modality also would provide pain relief and delay progression of the disease in the distal radius.

Methods: A review of 434 osteonecrosis patient records from the past 7 years in our prospectively collected database identified 4 patients (6 wrists) who had the disease in the distal radius. Two of these patients also had the disease in the ulna. All 4 patients were women, and their mean age was 46 years (range, 37 to 52 years). Clinical and radiographic outcomes were assessed at a mean of 39 months (range, 12 to 84) following treatment with core decompression. The clinical evaluations were conducted using the Michigan Hand Outcomes Questionnaire (MHQ). The reported pre-operative MHQ component scores for function, completion of everyday activities, pain, completion of work activities, overall appearance of the hands, and patient satisfaction were compared to the results of the MHQ at final follow-up. Radiographic success of the core decompressions was based on whether there was any progression in the stage of the disease.

Results: The most common risk factor for this cohort of patients was corticosteroids with 3 of the 4 patients having reported prior use. Other risk factors included alcohol consumption on a regular basis (n = 2), tobacco abuse (n = 2), blood dyscrasia (n = 2), and systemic lupus erythematosus (n = 1). Additionally, all 4 patients had multifocal osteonecrosis (affecting at least four separate anatomic sites. Overall, the patients reported a mean improvement in MHQ score (from 65% to 84%). Stratified by category, satisfaction improved from 64% to 88%, overall hand function increased from 64% to 81%, and pain was reduced from 60% to 25%, for pre- and post-operative values, respectively. One patient (2 wrists) required additional core decompressions in each wrist at one year following surgery but reported sustained improvement in her MHQ for both wrists at two years following her second core decompressions. There were no complications associated with the core decompressions, and there was no radiographic progression in the stage of the disease in any of the cases.

Discussion: Osteonecrosis of the distal radius is rarely found in patients with this disease (< 1%). It can be found in patients with osteonecrosis of other joints who have a symptomatic wrist and may have more than one risk factor. It can be readily diagnosed with x-rays and/or MRI. The results of the present study suggest that core decompression is a safe and effective treatment modality for symptomatic osteonecrosis of the wrist at the distal radius and/or ulna. Although the level of improvement in MHQ varied for each case, all patients reported reduced pain and improved function at final follow-up without any apparent complications. Based on these results, we recommend the use of core decompressions to alleviate the symptoms and to possibly delay the progression of distal radius osteonecrosis.

Introduction: Core decompression has historically been used during the early stages of osteonecrosis of the ankle as a treatment method to decrease pain and defer the eventual collapse of the joint. Originally, this procedure was described using large diameter trocars. The multiple locations of the lesions (such as the distal tibia and fibula, the talar dome, the calcaneus, and/or the metatarsals) and the relative small affected bones (compared to the femoral head and distal femur) make this procedure technically difficult. The investigators report on the treatment of osteonecrosis of the ankle with a new technique using multiple small percutaneous 3-mm perforations.

Methods: Between September, 2002 and May, 2004, the senior author treated 44 symptomatic ankles affected with osteonecrosis using the multiple perforation technique. The series included 31 patients (23 women, 8 men) who had a mean age at the time of surgery of 42 years (range, 17 to 61 years). All the procedures were performed using a 3-millimeter Steinman pin technique. Radiographic outcome was assessed during post-operative clinical visits using plain x-rays and magnetic resonance imaging. Clinical outcome was assessed postoperatively using the AOFAS (American Orthopaedic Foot and Ankle Society) score. Progression of the disease (defined as evidence of subchondral collapse or AOFAS score < =80 points) was correlated with demographic variables such as associated risk factors, prior surgical procedures, size, and location of the lesions.

Results: Ankle arthrodesis was avoided in 93% of the cases (41 of 44 ankles) at a mean follow-up of 3.6 years (range, 2 to 5 years). Forty of 44 ankles (91%) had a successful clinical outcome (AOFAS score ≥ 80 points). The AOFAS score for the entire series increased from a preoperative mean of 41 points (range, 34 to 55 points) to a postoperative mean of 88 points (range, 51 to 100 points). The AOFAS score for the series excluding the three ankles that required arthrodesis increased from a preoperative mean of 41 points to 91 points postoperatively. The three cases that required ankle arthrodesis presented initially with osteonecrosis of multiple bones about the ankle (talus, calcaneus, distal tibia and fibula) and two of these cases had HIV as an associated risk factor for osteonecrosis. All but 8 patients presented signs and symptoms of osteonecrosis in other joints (hip, knee, shoulder) and this had a negative correlation with outcome. There were no complications from the procedures, which were all performed as outpatient surgeries.

Discussion: The percutaneous perforations technique appears to be a low-morbidity method of relieving symptoms and deferring ankle arthrodesis (or other invasive procedures) in patients with symptomatic osteonecrotic ankles. The authors believe that these results support the need for a multicenter-randomized study comparing minimally invasive treatment options for osteonecrosis.

Introduction: Osteonecrosis of the hip is a devastating disease that often results in the collapse of the femoral head and secondary osteoarthritis of the hip. Although total hip arthroplasty is considered the main therapeutic option in cases of advanced osteonecrosis (Ficat stage III or IV), historically high failure rates have been reported for this treatment. Variables such as, whether or not the prosthesis was cemented, year of implantation, age, various medical comorbidities, and risk factors such as alcohol abuse, corticosteroids usage, autoimmune disease, or sickle cell anemia may lead to better or worse outcomes. The purpose of this study was to determine which factors were associated with risk for failure concerning total hip arthroplasty (THA) for osteonecrosis of the femoral head from a complete meta-analysis of the literature.

Methods: A systematic review utilizing the Medline bibliographic database found 35 studies meeting our inclusion criteria that were related to osteonecrosis encompassing 557 hips in 443 patients. These reports were published between the years 1989 to 2007. The mean follow-up was 6.7 years (range, 3 – 10). The study population comprised of 60% men who had a mean age of 47 years (range, 17 to 90). The most frequent associated risk factors for osteonecrosis were corticosteroid usage (26.2%) and alcohol abuse (30.1%). The final outcome parameters were number and percentage of patients who underwent revision surgery, who had impending radiographic failure, such as osteolytic lesions in close proximity to the implant, or who were clinical failures. Clinical failure was defined as a value less than 70% of the maximum score of the relevant hip scoring system used.

All reviewed studies were divided into cemented, cementless, or hybrid fixation, as well as year of implantation (before and after 1990). In addition, patients were stratified according to comorbidities, age, gender, and various diagnostic and other risk factors (e.g. systemic lupus erythematosus, sickle cell disease, use of corticosteroids, alcohol abuse).

Results: Overall, there were 131 poor outcomes out of 557 hips (23.5%). Seventy-six revision surgeries were performed, with another 55 hips showing either radiographic signs of loosening or clinical failures. Cemented THA had a failure rate of 17.9%, while the cementless THA had a failure rate of 24.5%.

Overall outcomes were different for various risk factors; intake of corticosteroids led to a failure rate of 42.3%, alcohol abuse; 38.1%, posttraumatic disorders; 39%, and sickle cell anemia; 45.5%. Patients without known adverse risk factors had only 17% failures.

Discussion: Our findings further emphasize the poor results of total hip arthroplasty in patients with various risk factors such as alcohol abuse, use of corticosteroids, lupus, and sickle cell anemia. It also appears that patients without these adverse risk factors have a better survival rate. The importance of this study is that it may help the surgeon understand the risk of total hip arthroplasty in various stratified groups in patients with osteonecrosis.

The Johns Hopkins University Department of Orthopaedics at the Good Samaritan Hospital, Baltimore, Maryland USA

Introduction: Historically, bone scintigraphy has been advocated as a useful diagnostic tool for patients with suspected osteonecrosis or in screening for multifocal disease. The principle aim of this study was to evaluate the sensitivity of bone scanning relative to magnetic resonance imaging in the diagnosis of osteonecrosis.

Methods: Forty-eight patients presented with suspected osteonecrosis of the shoulder, hip, knee, or ankle. All patients underwent simultaneous (less than three months apart) bone scans and magnetic resonance imaging studies as part of a diagnostic work-up. Histological confirmation of osteonecrosis was obtained for all suspected lesions in the study. The diagnostic yield for each imaging modality was then assessed and compared.

Results: All one hundred sixty-three (100%) histologically confirmed lesions were identified by magnetic resonance imaging, while only ninety-one lesions (56%) were identified by bone scan. There was complete uniformity of bone scans with magnetic resonance images in only 38% of patients (eighteen of forty-eight). Bone scanning identified 72% of lesions (forty-seven of sixty-five) in oligofocal patients (less than two involved joints) compared with 45% of the lesions (forty-four of ninety-eight) in multifocal patients (more than two joints involved). Sensitivity of the lesions was highest for the knee and hip and lower for the shoulder and ankle. Larger and later stage lesions had higher bone scan sensitivity.

Conclusions: The results of this study have demonstrated the low sensitivity of bone scintigraphy for diagnosing symptomatic osteonecrosis. Bone scanning did not detect 44% of the lesions (seventy-two of one hundred sixty-three). This study does not support the use of bone scans as a diagnostic or screening tool for this disease.

Introduction: Osteonecrosis of the femoral head is a devastating disease that often progresses to hip joint destruction necessitating total hip arthroplasty. The use of core decompression is typically recommended for patients with early small and medium-sized lesions. The reported efficacy of this procedure has been variable. Recently, various adjustments to the surgical technique have been described. There has been interest in performing multiple drillings under fluoroscopic guidance and combining core decompression with electrical stimulation and/or biological adjunctive growth factors. In order to assess whether the efficacy of this procedure has improved during the last 15 years using modern techniques, we compared recently reported radiographic and clinical success rates to results of surgeries performed prior to 1992. In addition, we evaluated the outcomes of our cohort of 52 patients (79 hips) who were treated with multiple small diameter drillings.

Method: A systematic review utilizing the Medline and Embase bibliographic databases found 59 studies meeting our inclusion criteria that were related to core decompression and osteonecrosis. The mean age for patients was 39 years (range, 9 to 83 years), and the mean follow-up was 56 months (range, 1 to 228 months). From these reports, there were 1,429 hips treated prior to 1992 and 1,957 hips since 1992. Other than the smaller percentage of Ficat stage III cases in the later studies, the reported etiologies and the stratification of preoperative Ficat stage were similar in the two strata of groups with the majority of patients being Ficat stage I and II and corticosteroids and alcohol being the most frequently reported associated diagnosis. From our institution, we identified 52 patients (79 hips) who had a core decompression utilizing a multiple small diameter (3 millimeters) technique at mean follow-up of 65 months. The outcome parameters collected for each core decompression patient at our institution and from the reports in literature were the number and percentage of patients who required additional surgeries, were clinical failures, or had radiographic progression of the disease.

Results: Overall, the success rates were higher for the studies that reported core decompressions performed during the last 15 years compared to procedures that were done prior to 1992. The proportion of patients surviving without additional surgery increased from 57% (range, 28 to 97%) in the earlier studies to 67% (range, 18 to 100%) in the more recent reports. Similarly, the radiographic success also increased from 54% (range, 0 to 94%) for the pre-1992 cohort to 59% (range, 22 to 90%). While clinical success increased from 57% (range, 28 to 94%) in the pre-1992 procedures to 61% (range, 29 to 90%) in reports from the last 15 years, this improvement was not statistically significant. Stratification by Ficat stage showed that there were significantly fewer patients who were Ficat stage III after 1992 suggesting that patient selection was the primary reason for the improvement in outcomes. For hips classified as Ficat stage II, there was an increase in clinical success and reduced percentage of patients requiring additional surgery in the more recent reports. The results of our cohort of patients were similar to other reports in the last 15 years. Patients who had small lesions and were Ficat stage I prior to treatment had the best results with 79% showing no radiographic progression.

Discussion: The results of the present study do not provide adequate evidence to suggest that recent techniques provide better clinical scores or radiographic outcomes. However, the additional accumulation of successful reports in the last decade confirms that core decompression is a safe and effective procedure for the treatment of early stages of osteonecrosis of the femoral head. Furthermore, these results suggest that proper patient selection can improve outcomes for this procedure. Based on the results of our experience as well as that of other studies, we will use core decompression to treat patients who have early small and medium-sized lesions and are Ficat stage I or II. Additionally, the mid-term follow-up of the multiple small diameter core decompression patients at our institution was longer than most studies, and had a success rate similar to, or higher than other reports, which confirms the use of this technique as the authors’ preferred method.