Paired bone marrow and peripheral blood samples demonstrate lack of widespread dissemination of some CH clones.

Clonal hematopoiesis (CH) represents clonal expansion of mutated hematopoietic stem cells detectable in the peripheral blood or bone marrow through next generation sequencing. The current prevailing model posits that CH mutations detected in the peripheral blood mirror bone marrow mutations with clones widely disseminated across hematopoietic compartments. We sought to test the hypothesis that all clones are disseminated throughout hematopoietic tissues by comparing CH in hip vs peripheral blood specimens collected at the time of hip replacement surgery. Here, we show that patients with osteoarthritis have a high prevalence of CH, which involve genes encoding epigenetic modifiers and DNA damage repair pathway proteins. Importantly, we illustrate that CH, including clones with variant allele frequencies >10%, can be confined to specific bone marrow spaces and may be eliminated through surgical excision. Future work will define whether clones with somatic mutations in particular genes or clonal fractions of certain sizes are either more likely to be localized or are slower to disseminate into the peripheral blood and other bony sites.

Concurrent Hardware Removal is Associated With Increased Odds of Infection Following Conversion Total Knee Arthroplasty.

BACKGROUND: The optimal timing of removal of periarticular implants prior to conversion total knee arthroplasty (TKA) remains to be determined. The purpose of this study was to compare infection rates in conversion TKA when hardware removal was performed in either a staged or concurrent manner. METHODS: We performed a retrospective study using a national insurance claims database of patients who underwent removal of hardware on the same day or within 1 year before their TKA. A total of 16,099 patients met the criteria. After matching, both final cohorts consisted of 4,502 patients. The 90-day and 1-year rates of prosthetic joint infection were calculated. RESULTS: The rates of infection were 1.64% and 3.00% in the staged group and 2.62% and 3.95% in the concurrent group at 90 days and 1 year postoperatively, respectively (P = .001, P = .01). Logistic regression analyses demonstrated that patients who had hardware removal greater than 3 months prior to TKA had significantly lower odds of infection at 1-year postop (Odds Ratio 0.61 95% Confidence Interval 0.45-0.84; P = .003). CONCLUSION: Removal of hardware performed concurrently or within 3 months of a TKA is associated with increased odds of prosthetic joint infection at 1 year postoperatively. Surgeons should consider removing periarticular hardware prior to TKA when possible.

Wagner Cone Midterm Survivorship and Outcomes.

BACKGROUND: Total hip arthroplasty (THA) in patients with abnormal proximal femoral anatomy requires an individualized treatment approach to prevent complications. Metaphyseal engaging stems in this population risk fracture, size/offset mismatch, and aseptic loosening. The Wagner conical femoral implant is a short diaphyseal engaging femoral stem that could improve treatment success in this difficult patient population. METHODS: We identified 302 consecutive patients undergoing THA using the Wagner cone femoral prosthesis between January 2010 and January 2017. Clinical, radiographic, and patient-reported outcomes were obtained through chart review and radiographic measurements of postoperative X-rays. We used multivariate analysis to determine predictors of poor outcomes. Kaplan-Meier curves were created to demonstrate implant survivorship with reoperation and revision as endpoints. The average follow-up was 3.2 years, with a minimum of 2 years. RESULTS: The implant retention survival rate during the 3.2-year study period was 98.7%. The overall reoperation rate was 4.2%, with infection followed by fracture being the most common reasons for reoperation. No patients were revised for aseptic loosening, and no patients were revised for subsidence. The average subsidence was 1.1 mm. The Harris Hip Score improved from 48.6 ± 7.3 (range, 28-64) preoperatively to 86.1 ± 8.5 (range, 66-100) at latest follow-up. The patient-reported satisfaction rate was 98.3%. CONCLUSION: The Wagner cone femoral prosthesis demonstrated excellent clinical, radiographic, and patient-reported functional outcomes at midterm follow-up. We recommend use of the Wagner cone in THA patients with challenging proximal femoral anatomy, small femoral diameter, or poor metaphyseal bone quality.