Screw fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series was the evaluation of screw misplacement rate and functional outcome of percutaneous screw fixation of pelvic ring disruptions using a 2D navigation system.

The major burden of knee joint osteoarthritis (OA) is pain. Since in elder patients diabetes mellitus is an important comorbidity of OA, we explored whether the presence of diabetes mellitus has a significant influence on pain intensity at the end stage of knee OA, and we aimed to identify factors possibly related to changes of pain intensity in diabetic patients. In 23 diabetic and 47 nondiabetic patients with OA undergoing total knee arthroplasty, we assessed the pain intensity before the operation using the “Knee Injury and Osteoarthritis Outcome Score”. Furthermore, synovial tissue, synovial fluid (SF), cartilage, and blood were obtained. We determined the synovitis score, the concentrations of prostaglandin E₂ and interleukin-6 (IL-6) in the SF and serum, and of C-reactive protein and HbA1c and other metabolic parameters in the serum. We performed multivariate regression analyses to study the association of pain with several parameters. Diabetic patients had on average a higher Knee Injury and Osteoarthritis Outcome Score pain score than nondiabetic patients (P < 0.001). Knee joints from diabetic patients exhibited on average higher synovitis scores (P = 0.024) and higher concentrations of IL-6 in the SF (P = 0.003) than knee joints from nondiabetic patients. Multivariate regression analysis showed that patients with higher synovitis scores had more intense pain independent of all investigated confounders, and that the positive association between pain intensities and IL-6 levels was dependent on diabetes mellitus and/or synovitis. These data suggest that diabetes mellitus significantly increases pain intensity of knee OA, and that in diabetic patients higher pain intensities were determined by stronger synovitis.

The standard for operative treatment of acetabular fractures is open reduction and plate fixation. Recently, screw fixation-only methods through less invasive approaches are reported, but biomechanical data are missing. Questions posed in this study are (1) is the static fixation strength of different screw types equivalent to the standard plate fixation for anterior column fractures of the acetabulum? and (2) does the placement of an additional screw in the infra-acetabular corridor increase the fixation strength independent of the used implant? Three groups of different screws (group II, titanium; group III, stainless steel; and group IV, biodegradable Poly-L-Lactid) were compared with the standard plate fixation (group I) in Synbone pelves with custom-made anterior column fractures. Six pelvises per group were axial loaded with six cycles of 800 N, twice with and without an additional placed infra-acetabular screw. The fixation strength of titanium screws was equivalent to the standard plate fixation. The stainless steel and Poly-L-Lactid screw fixation strengths were equivalent to each other but inferior to the aforementioned. The additional placement of an infra-acetabular screw significantly increased the fracture fixation strength, independent of the used implant. Screw fixation is a promising alternative approach for the stabilization of noncomminuted acetabular fractures of the anterior column with equivalent fixation strength to the standard plate fixation. The additional placement of an infra-acetabular screw significantly increases the fracture fixation independent of the used implant and should be considered for acetabular fractures with separation of both columns. Therapeutic study, level IV.