Patients with Revision Modern Megaprostheses of the Distal Femur Have Improved Disease-Specific and Health-Related Outcomes Compared to Those with Primary Replacements.

We asked whether there would be any difference between primary and revision modern cemented fixed hinge megaprosthesis of the distal femur in function and activity-related outcomes following treatment of a bone tumor. An identical custom-made fixed hinge cemented megaprosthesis with a hydroxyapatite collar was used in all cases. The main outcomes were joint-specific function, disease-specific activity, and health-related quality of life. Implant survival was also evaluated. Patients in the revision group performed slightly better than patients in the primary group on disease-specific (Toronto Extremity Salvage Score, p = 0.033; Musculoskeletal Tumor Society, p = 0.072) and health-related outcomes (Short Form 36 [SF-36] physical component, p = 0.085; SF-36 mental component, p = 0.069) but not on joint-specific outcomes (Knee Society Score, p = 0.94). The cumulative probabilities of revision for any reason were 14.5% (7-25%) at 5 years with no statistically significant difference between primary and revision procedures (p = 0.77). In conclusion, patients undergoing a revision have similar joint-specific functional outcome but improved disease-specific and health-related outcomes. Implant survival are similar between groups.

Distraction to treat knee osteoarthritis.

The objective of this article is to review data on joint distraction used to treat knee osteoarthritis. Joint distraction is a surgical procedure in which the two bony ends of the joint are gradually pulled apart then kept separated for 2 months in an external fixation frame. Weight bearing is continued to ensure variations in hydrostatic pressure within the joint. In published studies, joint distraction provided substantial clinical and structural improvements in patients with knee osteoarthritis, delaying joint replacement surgery for at least 2 years. Animal studies showed that joint distraction was associated with decrease in the secondary inflammatory response, cartilage breakdown, and subchondral bone remodeling. In vitro, the intermittent application of hydrostatic pressure stimulated the production of extracellular matrix, particularly in joints with osteoarthritis. Nevertheless, several considerations invite caution when considering the more widespread use of joint distraction. Published studies have short follow-ups and small sample sizes. In addition, the high frequency of pin tract infection is of concern, since most patients eventually require knee replacement surgery. These two considerations indicate a need for longer-term prospective studies of patient cohorts.

Osteogenic progenitors in bone marrow aspirates have clinical potential for tibial non-unions healing in diabetic patients.

PURPOSE: There is a significantly higher incidence of delayed unions, non-unions, and increased healing time in diabetic patients compared with non-diabetic patients. Studies suggest that diabetics suffer from deficiencies of pancreatic stem/progenitor cells, and a clinically relevant question arises concerning the availability and functionality of progenitor cells obtained from bone marrow of diabetics for applications in bone repair. METHODS: We have evaluated the cellularity and frequency of osteogenic mesenchymal stem cells (MSCs) in bone marrow from 54 diabetic patients (12 with type 1 and 42 with type 2) with tibial non-unions. These patients were treated with bone marrow MSCs (BM-MSCs) delivered in an autologous bone marrow concentrate (BMC). Clinical outcomes and marrow cellularity were compared to 54 non-diabetic, matched patients with tibial non-unions also treated with BMC. RESULTS: After adjusting for age and sex, no differences were identified with respect to bone marrow cellularity and MSC number among the diabetic and non-diabetic groups and both groups received approximately the same number of MSCs on average. BMC treatment promoted non-union healing in 41 diabetic patients (76 %) and 49 non-diabetic patients (91 %), but the non-diabetic patients healed more quickly and produced a larger volume of callus. CONCLUSION: We recommend that diabetic patients be treated with an increased number of progenitor cells by increasing the bone marrow aspiration volume. We also anticipate a need to extend the time of casting and non-weight bearing for diabetic patients as compared with non-diabetic patients.

Multifocal osteonecrosis related to corticosteroid: ten years later, risk of progression and observation of subsequent new osteonecroses.

PURPOSE: No study has reported the risk of other site osteonecroses after the diagnosis of multifocal osteonecrosis related to corticosteroids in patients who continue this corticosteroid treatment. An analysis of the time-course to other sites of osteonecrosis, as well as the effects of underlying corticosteroid risk factor on the evolution of asymptomatic lesions at the time of diagnosis, is presented. METHODS: Two hundred patients were followed prospectively every year during a minimum ten years with a radiograph if a joint became symptomatic. In absence of evidence of osteonecrosis on radiographs of a symptomatic or non-symptomatic joint (hips, shoulders, knees, ankles), patients had an MRI performed at the most recent follow up. The average duration of follow-up after inclusion of the patient in the study was 15 years (range 10-20). RESULTS: Of the 200 patients followed for an average of 15 years (minimum 10 years, maximum 20 years), 35 patients developed new osteonecrosis lesions during the period of study. Asymptomatic lesions became symptomatic and a high number of collapse was observed resulting in 258 arthroplasties (187 hips, 51 shoulders, 20 knees) at the most recent follow up. CONCLUSION: The continuation of peak doses (>200 mg) of corticosteroids predicted (p = 0.04) occurrence of new lesions and the continuation of corticosteroids without peak dose was a risk for quicker progression to collapse.