Conventional anatomically contoured plates do not adequately fit most tibiae. This emphasizes the need for a more thorough morphological study. Statistical shape models are promising tools to display anatomical variations within a population. Herein, we aim to provide a better insight into the anatomical variations of the tibia and tibia plateau. Seventy-nine CT scans of tibiae were segmented, and a principal component analysis was performed. Five morphologically important parameters were measured on the 3D models of the mean tibial shapes as well as the −3SD and +3 SD tibial shapes of the first five components. Longer, wider tibiae are related to a more rounded course of the posterior column, a less prominent tip of the medial malleolus, and a more posteriorly directed fibular notch. Varus/valgus deformations and the angulation of the posterior tibia plateau represent only a small percentage of the total variation. Right and left tibiae are not always perfectly symmetrical, especially not at the level of the tibia plateau. The largest degree of anatomical variation of the tibia is found in its length and around the tibia plateau. Because of the large variation in the anatomy, a more patient-specific approach could improve implant fit, anatomical reduction, biomechanical stability and hardware-related complications.

Background: Fractures of the pubic ramus without involvement of the posterior pelvic ring represent a minority of fragility fractures of the pelvis (FFP). The natural history of patients suffering this FFP Type I has not been described so far. Material and methods: All patients, who were admitted with isolated pubic ramus fractures between 2007 and mid-2018, have been reviewed. Epidemiologic data, comorbidities, in-hospital complications, and one-year mortality were recorded. Of all surviving patients, living condition before the fracture and at follow-up was noted. Mobility was scored with the Parker Mobility Score, quality of life with the European Quality of Life 5 Dimensions 3 Level (EQ-5D-3L), subjective sensation of pain with the Numeric Rating Scale (NRS). Results: A consecutive series of 138 patients was included in the study. There were 117 women (84.8%) and 21 men (15.2%). Mean age was 80.6 years (SD 8.6 years). 89.1% of patients presented with comorbidities, 81.2% of them had cardiovascular diseases. Five patients (4%) died during hospital-stay. Median in-hospital stay was eight days (2–45 days). There were in-hospital complications in 16.5%, urinary tract infections, and pneumonia being the most frequent. One-year mortality was 16.7%. Reference values for the normal population of the same age are 5.9% for men and 4.0% for women. One-year mortality rate was 22.2% in the patient group of 80 years or above and 8.8% in the patient group below the age of 80. The rate of surviving patients living at home with or without assistance dropped from 80.5% to 65.3%. The median EQ-5D-Index Value was 0.62 (0.04–1; IQR 0.5–0.78). Reference value for the normal population is 0.78. Average PMS was 4 and NRS 3. Within a two-year period, additional fragility fractures occurred in 21.2% and antiresorptive medication was taken by only 45.2% of patients. Conclusion. Pubic ramus fractures without involvement of the posterior pelvis (FFP Type I) are serious adverse events for elderly persons. During follow-up, there is an excess mortality, a loss of independence, a restricted mobility, and a decreased quality of life. Pubic ramus fractures are indicators for the need to optimize the patient’s general condition.

Introduction: In fragility fractures of the pelvis (FFP), fractures of the posterior pelvic ring are nearly always combined with fractures of the anterior pelvic ring. When a surgical stabilization of the posterior pelvis is performed, a stabilization of the anterior pelvis is recommended as well. In this study, we aim at finding out whether conventional plate osteosynthesis is a valid option in patients with osteoporotic bone.Materials and methods: We retrospectively reviewed medical charts and radiographs of all patients with a FFP, who underwent a plate osteosynthesis of the anterior pelvic ring between 2009 and 2019. Patient demographics, fracture characteristics, properties of the osteosynthesis, complications and revision surgeries were documented. Single plate osteosynthesis (SPO) at the pelvic brim was compared with double plate osteosynthesis (DPO) with one plate at the pelvic brim and one plate anteriorly. We hypothesized that the number and severity of screw loosening (SL) or plate breakage in DPO are lower than in SPO.Results: 48 patients with a mean age of 76.8 years were reviewed. In 37 cases, SPO was performed, in 11 cases DPO. Eight out of 11 DPO were performed in patients with FFP type III or FFP type IV. We performed significantly more DPO when the instability was located at the level of the pubic symphysis (p = 0.025). More patients with a chronic FFP (surgery more than one month after diagnosis) were treated with DPO (p = 0.07). Infra-acetabular screws were more often inserted in DPO (p = 0.056). Screw loosening (SL) was seen in the superior plate in 45% of patients. There was no SL in the anterior plate. There was SL in 19 of 37 patients with SPO and in 3 of 11 patients with DPO (p = 0.16). SL was localized near to the pubic symphysis in 19 of 22 patients after SPO and in all three patients after DPO. There was no SL in DPO within the first month postoperatively. We performed revision osteosynthesis in six patients (6/48), all belonged to the SPO group (6/37). The presence of a bone defect, unilateral or bilateral anterior pelvic ring fracture, post-operative weight-bearing restrictions, osteosynthesis of the posterior pelvic ring, and the presence of infra- or supra-acetabular screws did not significantly influence screw loosening in SPO or DPO.Conclusion: There is a high rate of SL in plate fixation of the anterior pelvic ring in FFP. In the vast majority, SL is located near to the pubic symphysis. DPO is associated with a lower rate of SL, less severe SL and a later onset of SL. Revision surgery is less likely in DPO. In FFP, we recommend DPO instead of SPO for fixation of fractures of the anterior pelvic ring, which are located in or near to the pubic symphysis.