Finite Element Analysis of Different Osseocartilaginous Reconstruction Techniques in Animal Model Knees

Lesions of the articular cartilage are frequent in all age populations and lead to functional impairment. Multiple surgical techniques have failed to provide an effective method for cartilage repair. The aim of our research was to evaluate the effect of two different compression forces on three types of cartilage repair using finite element analysis (FEA). Initially, an in vivo study was performed on sheep. The in vivo study was prepared as following: Case 0-control group, without cartilage lesion; Case 1-cartilage lesion treated with macro-porous collagen implants; Case 2-cartilage lesion treated with collagen implants impregnated with bone marrow concentrate (BMC); Case 3-cartilage lesion treated with collagen implants impregnated with adipose-derived stem cells (ASC). Using the computed tomography (CT) data, virtual femur-cartilage-tibia joints were created for each Case. The study showed better results in bone changes when using porous collagen implants impregnated with BMC or ASC stem cells for the treatment of osseocartilaginous defects compared with untreated macro-porous implant. After 7 months postoperative, the presence of un-resorbed collagen influences the von Mises stress distribution, total deformation, and displacement on the Z axis. The BMC treatment was superior to ASC cells in bone tissue morphology, resembling the biomechanics of the control group in all FEA simulations.

The impact of proton pump inhibitors on bone regeneration and implant osseointegration

Proton pump inhibitors (PPIs) have become known for the treatment of gastric-acid related disorders. Similar to any other drugs, PPIs have possible adverse reactions, being associated with bone fractures, infections, kidney disease, mineral deficiency, dementia, and pneumonia. Multiple analyses have stated that PPIs therapy may affect bone regeneration and osseointegration process, causing an increased risk of bone fracture, deterioration of bone metabolism and impaired bone healing. In this review, we emphasized the current literature regarding the influence of proton pump inhibitors in the bone regeneration process. Results from the studies suggest a link between PPIs intake and bone regeneration, but several concerns are raised regarding inadequate recipient bone, surgical trauma, limitations on the titanium surface, comorbidities or interference with other pharmacological agents. Further studies are needed to determine whether the impaired bone regeneration process is due to PPI or coexisting factors.