Bone defects can result from different incidents such as acute trauma, infection or tumor resection. While in most instances bone healing can be achieved given the tissue's innate ability of self-repair, for critical-sized defects spontaneous regeneration is less likely to occur, therefore requiring surgical intervention. Current clinical procedures have failed to adequately address this issue. For this reason, bone tissue engineering (BTE) strategies involving the use of synthetic grafts for replacing damaged bone and promoting the tissue's regeneration are being investigated. The electrical stimulation (ES) of bone defects using direct current has yielded very promising results, with neo tissue formation being achieved in the target sites
Mesenchymal stromal cells (MSC) have been proposed as an emerging cell therapy for bone tissue engineering applications. However, the healing capacity of the bone tissue is often compromised by patient's age and comorbidities, such as osteoporosis. In this context, it is important to understand the impact of donor age on the therapeutic potential of MSC. Importantly, the impact on donor age is not restricted to cells themselves but also to their microenvironment that is known to affect cell function. The extracellular matrix (ECM) has an important role in stem cell microenvironment, being able to modulate cell proliferation, self-renewal and differentiation. Decellularized cell-derived ECM (dECM) has been explored for regenerative medicine applications due to its bioactivity and its resemblance to the
Periprosthetic infection is a challenging complication of total knee arthroplasty (TKA) which reported incidence varies from 1 to 2% in primary TKA and 3–5% in revision TKA. Persistent infection of TKA may benefit from knee arthrodesis when all reconstruction options have failed. Knee arthrodesis also demonstrated better functional results and pain relief than other salvage procedures such as above-knee amputation. The purpose of this study was to analyze treatment results in patients who underwent knee arthrodesis following infected TKA. Retrospective study with review of the data of all patients treated in our department with knee arthrodesis for chronic infection of knee arthroplasty between 2009 and 2014. Clinical and radiographic data were evaluated as well as several variables: technique used, fusion rate, time to fusion, need for further arthrodesis and complications. Patients with less than 8 months of follow-up were excluded from this study. 46 patients were treated with knee arthrodesis in our department from 2009 to 2014 for chronic infection of total knee arthroplasty. The sample included 26 (57%) women and 20 (43%) men, median age of 70 years. In 45 patients, the technique used was compressive external fixation, while an intramedullary modular nail was used in 1 patient. Mean follow-up of these patients was 35 months (8–57). Primary knee fusion was obtained in 32 (70%) patients with a mean time to fusion of 5,8 months (4–9). 9 (20%) patients needed rearthrodesis and 7 (15%) ultimately achieved fusion. 33 (72%) patients underwent knee arthrodesis in a single surgical procedure, while 13 (28%) firstly removed knee arthroplasty and used a spacer before arthrodesis. Overall complication rate was 35%; 7 (15%) patients experienced persistent infection and 4 (9%) of these undergone above knee amputation. Treatment of septic total knee replacement is a surgical challenge. Compressive external fixation was the method of choice to perform knee arthrodesis following chronic infected TKA. Although complication rate was worrisome, overall fusion rate was satisfactory and this arthrodesis method can be safely performed in one stage.
