Prospective single-center cohort study to record additional time requirements and radiation dose in navigation-assisted O-arm-controlled pedicle screw (PS) instrumentations. To evaluate amount of extra-time and radiation dose for navigation-assisted PS instrumentations of the thoracolumbosacral spine using O-arm 3D-real-time-navigation (O3DN) compared to non-navigated spinal procedures (NNSP) with a single C-arm and postoperative computed tomography (CT) scan for controlling PS positions. 3D-navigation is reported to enhance PS insertion accuracy. But time consuming navigational steps and considerable additional radiation doses seem to limit this modern technique's attraction. A detailed analysis of additional time demand and extra-radiation dose in 3D-navigated spine surgery is not provided in literature, yet. From February 2011 through July 2015, 306 consecutive posterior instrumentations were performed in vertebral levels T10-S1 using O3DN for PS insertion. The duration of procedure-specific navigational steps of the overall collective (I) and the last cohort of 50 consecutive O3DN-surgeries (II) was compared to the average duration of analogous surgical steps in 100 consecutive NNSP using a single C-arm. 3D-radiation dose (dose-length-product, DLP) of navigational and post-instrumentation O-arm scans in group I and II was compared to the average DLP of 100 diagnostic lumbar CT scans. The average pre-surgical time from patient positioning on the operating table to skin incision was 46.2 ± 10.1 minutes (O3DN, I) and 40.6 ± 9.8 minutes (O3DN, II) vs. 30.6 ± 8.3 minutes (NNSP) (p < 0.001, each). Intraoperative interruptions for scanning and data processing took 3.0 ± 0.6 minutes. DLPs averaged 865.1 ± 360.8 mGycm (O3DN, I) and 562.1 ± 352.6 mGycm (O3DN, II) compared to 575.5 ± 316.5 mGycm in diagnostic lumbar CT scans (p < 0.001 (I), p≈0.81 (II)). After procedural experience, navigated surgeries can be performed with an additional time demand of 13.0 minutes compared to NNSP, and with a total DLP below that of a diagnostic lumbar CT scan (p≈0.81). Level of Evidence: 4

Nondisplaced and minimally displaced sacral insufficiency fractures are increasingly being recognized as a cause of immobilizing low back pain in the elderly. These insufficiency fractures are most accurately diagnosed by visualizing sacral bone marrow edema on magnetic resonance imaging, which is the radiologic imaging modality with the highest sensitivity for identifying these fractures. Successful treatment options range from nonsurgical (eg, bed rest, pain medication, mobilization, antiosteoporotic medication, low-intensity-pulsed ultrasound, etc.) to surgical management (ie, sacroplasty and/or osteosynthesis with iliosacral screws or lumbosacral hinge fixation with or without application of reinforcing bone cement). The appropriate surgical treatment for frail subjects requires a less-invasive technique that establishes full weight-bearing stability for successful early remobilization of affected elderly and multimorbid individuals. Iliosacral screw osteosynthesis with a single C-arm is a common surgical technique for stabilizing the posterior pelvic ring after traumatic instabilities or fractures of the sacrum. Bilateral injuries are generally addressed from both sides of the pelvis. This article describes the surgical technique of 3D image-guided transsacral screw fixation for unilateral and bilateral nondisplaced sacral insufficiency fractures in the elderly using a single-sided approach, and specifies the associated preoperative and postoperative management. The procedure is illustrated in an instructional video that demonstrates step-by-step, how the navigated surgical procedure is performed.

Surgical treatment for sacral fragility fractures using navigation-assisted screw fixation (NSF) is a modern, technically demanding procedure. Additional sacroplasty (ASP) has been shown to provide only insignificant clinical benefits for patients. This investigation highlights procedural economic aspects and evaluates results with regard to resource scarcity in order to be able to decide, whether ASP has a justification in NSF procedures beyond clinical aspects. From February 2011 to May 2017, all individuals with sacral fragility fractures surgically treated using 3D-fluoroscopy for NSF (n = 26) or NSF + ASP (n = 26) were enrolled. Outcome parameters were operative time, 3D-/2D-radiation dose, 2D-fluoroscopy time, material costs and reimbursement. In the two groups, a total of 52 individuals with 124 fragility fracture sites in sacral vertebrae I and II were surgically treated with similar numbers of screws inserted (p ≈ 0.679) requiring similar 3D- (p ≈ 0.546) and 2D-fluoroscopy radiation doses (p ≈ 0.236). In procedures with ASP, average 2D-fluoroscopy time (46.6 s vs. 32.7 s, p ≈ 0.004), and mean surgical duration (119 min vs. 96 min, p ≈ 0.011) were significantly longer. Mean implant costs (EUR 668.68 vs. EUR 204.34, p < 0.001), and reimbursement (EUR 8416.01 vs. EUR 6584.49, p ≈ 0.006) were significantly higher. Although comparison of costs and reimbursements indicated a positive financial balance, profitability was not confirmed, because financial expense for extended operative time prevented an economic advantage of procedures with ASP in this investigation. A formula was developed based on presented study data to allow similar economical decisions in other health care systems or institutions with differing resource costs.

Introduction: Performing total joint replacements (TJR) in patients with solid organ transplantations (SOT) is associated with an increased risk of complications and reoperation. The aim of this study is to report on implant survivorship, patient survivorship, and complication rates for total knee arthroplasty (TKA) and total hip arthroplasty (THA) performed in heart, lung, liver and kidney transplant recipients. Materials and methods: Forty patients with heart, lung, liver, or kidney transplants who underwent primary THA or TKA between January 1, 2013, and July 31, 2023, were included. Implant survivorship, reoperation-free survivorship, patient survivorship, and complication rates were compared between the subgroups. Results: At a mean follow-up of 5.18 years, Implant survivorship and reoperation-free survival for the entire cohort at the last follow-up were 97.5% and 85%, respectively. Kaplan–Meier survival estimates demonstrated 5- and 10-year reoperation-free survival rates of 86.5% (95% CI: 76%–98.4%) and 57.6% (95% CI: 25.6%–100%), respectively. The lung transplant group had the shortest reoperation-free survival, although not statistically significant (p = 0.07), a significantly higher risk of reoperation, with a hazard ratio (HR) of 6.9 (95% CI: 1.1–41.2, p = 0.04) and both the lowest 5-year patient survivorship at 68.6% (p = 0.04) and the highest risk of death after TJR with a HR of 7 (95% CI: 1.2–45.5, p = 0.03). Conclusion: Patients with SOT exhibit excellent mid-term implant survivorship, with a rate of 97.5%. Lung transplant recipients show the lowest rates of both reoperation-free survival and overall patient survivorship compared to heart, kidney, and liver transplant recipients. Despite this, the 90-day complication rates are similar across all organ groups.

Background/Objectives: Magnetic resonance imaging (MRI) is the preferred diagnostic means to visualize spinal pathologies, and offers the possibility of precise structural tissue analysis. However, knowledge about MRI-based measurements of physiological cross-sectional musculoskeletal dimensions and associated tissue-specific average structural brightness in the lumbar spine of healthy young women and men is scarce. The current study was planned to investigate characteristic intersexual differences and to provide MRI-related musculoskeletal baseline values before the onset of biological aging. Methods: At a single medical center, lumbar MRI scans of 40 women and 40 men aged 20–40 years who presented with moderate nonspecific low back pain were retrospectively evaluated for sex-specific differences in cross-sectional sizes of the fifth lumbar vertebrae, psoas and posterior paravertebral muscles, and respective sex- and age-dependent average brightness alterations on T2-weighted axial sections in the L5-level. Results: In women (mean age 33.5 years ± 5.0 (standard deviation)), the investigated musculoskeletal cross-sectional area sizes were significantly smaller (p < 0.001) compared to those in men (mean age 33.0 years ± 5.7). Respective average musculoskeletal brightness values were higher in women compared to those in men, and most pronounced in posterior paravertebral muscles (p < 0.001). By correlating brightness results to those of subcutaneous fat tissue, all intersexual differences, including those between fifth lumbar vertebrae and psoas muscles, turned out to be statistically significant. This phenomenon was least pronounced in psoas muscles. Conclusions: Lumbar musculoskeletal parameters showed significantly larger dimensions of investigated anatomical structures in men compared to those in women aged 20–40 years, and an earlier onset and faster progress of bone loss and muscle degradation in women.