High-grade trochlear dysplasia is the primary risk factor for patellofemoral instability and is frequently treated by trochleoplasty (trochlear osteotomy). In the thin-flap technique, which is widespread in German-speaking countries, the osteochondral flap formed is fixed and stabilized using Vicryl tape (Ethicon, Cornelia, GA, USA). Due to the discontinuation of the production of Vicryl tape, a modification of the original technique is required. The following surgical technique describes an alternative fixation method using absorbable suture pairs instead of the tape.

Eine hochgradige Trochleadysplasie ist der primäre Risikofaktor einer patellofemoralen Instabilität und wird häufig mittels vertiefender Trochleaplastik (Trochlea-Osteotomie) behandelt. Bei der im deutschen Sprachraum weit verbreiteten „Thin-flap-Technik“ wird der gebildete osteochondrale Lappen mittels Vicryl-Tapes (Ethicon, Cornelia, GA, USA) fixiert und stabilisiert. Durch die Einstellung der Produktion der Vicryl-Tapes bedarf es einer Modifikation der ursprünglichen Technik. Die nachfolgend vorgestellte Operationstechnik beschreibt eine alternative Fixationsmethode mit fünf resorbierbaren Fadenpaaren anstelle der Tapes.

Background: The incidence of injuries on alpine ski slopes have been assessed using various methods. A decline in injury rate has been observed throughout the literature; however, the actual incidence remains unclear. The purpose of this study was therefore to evaluate the incidence of skiing and snowboarding injuries using largesample data from an entire geographic state. Methods: Data on alpine injuries over the course of five winter seasons between 2017 and 2022 were prospectively collected from the emergency service dispatch center of Tyrol (Austria). The incidence of injuries was assessed in relation to the number of skier days, which was obtained from the chamber of commerce. Results: A total of 43,283 cases were identified, and a total of 98.1 Mio skier days were registered during the inclusion period of our study, resulting in an overall incidence of 0.44 injuries per 1,000 skier days. This is significantly less than reported from previous studies. From 2017/18 to 2021/22 there was a slight increase in injuries per 1000 skier days with an exception only for the COVID-19 related season 2020/21. Conclusion: Our study showed a significant reduction in the incidence of alpine skiing and snowboarding injuries in comparison with previous studies and should be considered a benchmark for future studies. Long-term studies on the efficacy of safety gear, as well as the influence of ski patrol and air-borne rescues on patient outcome are warranted.

To determine whether the preoperative degree of degeneration of the patellofemoral joint really affects the outcome of total knee arthroplasty (TKA) surgery without patella resurfacing and thus to establish a parameter that might serve as a guiding factor to decide whether or not to perform retropatellar resurfacing. It was hypothesized that patients with preoperative mild patellofemoral osteoarthritis (Iwano Stages 0–2) would significantly differ from patients with preoperative severe patellofemoral osteoarthritis (Iwano Stages 3–4) in terms of patient-reported outcome (Hypothesis 1) and revision rates/survival (Hypothesis 2) after TKA without patella resurfacing. Application of a retrospective–comparative design on the basis of Arthroplasty Registry data that included patients with primary TKA without patella resurfacing. Patients were allocated to the following groups based on preoperative radiographic stage of patellofemoral joint degeneration: (a) mild patellofemoral osteoarthritis (Iwano Stage ≤ 2) and (b) severe patellofemoral osteoarthritis (Iwano Stages 3–4). The Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) score was assessed preoperative and 1 year postoperative (0: best, 100 worst). In addition, implant survival was calculated from the Arthroplasty Registry data. In 1209 primary TKA without patella resurfacing, postoperative WOMAC total and WOMAC subscores did not differ significantly between groups, but potentially suffered from type 2 error. Three-year survival was 97.4

The purpose of the present study was to investigate associations between revision-free survival and functional scores of total knee arthroplasty (TKA) and moon phase on the day of surgery, as well as operations performed on a Friday 13th. The data of all patients that received TKA between 2003 and 2019 were extracted from the Tyrol arthroplasty registry. Patients that had undergone previous total or partial knee arthroplasty as well as patients that had missing pre- or post-operative WOMAC were excluded. Patients were allocated to one of the following four groups according to moon phase on the day of surgery: new, waxing, full and waning. Patients operated on a Friday 13th were also identified and compared to patients operated on any other days/dates. A total of 5923 patients met the inclusion criteria, with mean age of 69 ± 9 years, and comprising 62% women. There were no significant differences in revision-free survival among the four moon phase groups (p = 0.479), and no significant differences in preoperative and postoperative total WOMAC (p = 0.260, p = 0.122), There were no significant differences in revision-free survival patients operated on Friday 13th vs. other days/dates (p = 0.440). The preoperative total WOMAC was significantly worse for patients operated on a Friday 13th (p = 0.013), which was observed in the pain (p = 0.032) and function (p = 0.010) subscales. There were no significant differences in postoperative total WOMAC at 1 year follow-up (p = 0.122). Neither moon phase on the day of surgery nor Friday 13th were associated with revision-free survival or clinical scores of TKA. Patients operated on a Friday 13th had significantly worse preoperative total WOMAC but similar postoperative total WOMAC at 1-year follow-up. These findings could help reassure patients that TKA renders consistent outcomes regardless of the preoperative pain or function, and in spite of bad omens or moon phases.

Purpose Arthroplasty registries gained increasing importance to the re-certification of orthopaedic implants according to the European Union (EU) Medical Device Regulation (MDR) adopted in 2017. Until recently, several European countries only had regional arthroplasty registries. Whether regional registries deliver data quality comparable with national registries remained unclear. Therefore, the purpose of this study was to validate the Austrian Tyrolean Hip Arthroplasty Registry (THAR) and to evaluate if this regional registry showed adequate adherence, completeness and correctness when compared with well-established national registries. Methods A consecutive series of 1100 primary total hip arthroplasties were identified from our institution’s medical database. Patients were interviewed by phone and completed questionnaires after a mean follow-up period of 8.05 years and were asked if they had had revision surgeries. The data were compared to the corresponding dataset from the THAR. Results Adherence was 97.91% for primary total hip arthroplasty. Clinical follow-up identified 10 missing cases, resulting in adherence of 81.48% for revisions. Completeness of patient-reported outcome measurements was 78.55% before surgery and 84.45% 1 year after surgery. Correctness was 99.7% for demographic data, 99.54% for implant specifications, and 99.35% for mode of fixation. Conclusion The data of this study showed that regional arthroplasty registries can deliver data quality comparable with well-established national registries. The main reason for unrecorded revision cases and wrongly recoded implants was human error. Further digitalization with more automatic data submission may have the potential to reduce these failure rates in the future. Overall, the THAR represents a valid data source for re-certification of medical implants according to the EU’s MDR.

Background: Intraosseous access is a recommended alternative to venous access in emergencies. For its application, knowledge of the correct insertion depth is indispensable. We aimed to determine sex-specific differences on the appropriate insertion depth for intraosseous access in adults at the insertion sites most frequently used, namely the proximal and distal tibia and the proximal humerus. Methods: In this exploratory retrospective study, we measured thickness of soft tissue cover, cortex and cancellous bone along the puncture line on magnetic resonance images or computed tomography scans. Inclusion criteria were both sexes, 18–90 years of age and appropriate image quality. Primary outcome was the appropriate insertion depth to reach the cancellous bone for each sex. This was defined as the corridor between (i) the sum of the soft tissue cover and the cortex and (ii) the sum of (i) plus the diameter of the cancellous bone. Secondary outcomes were the differences in thickness of each layer between sexes. Results: In 179 females and males, the appropriate insertion depth was 32.5–45.5 mm and 20.5–42.0 mm in the proximal tibia, 14.5–30.5 mm and 16.5–34.5 mm in the distal tibia, and 27.5–52.5 mm and 26.0–56.5 mm in the proximal humerus. Although females had a thicker soft tissue cover (+6.8 mm [95% CI 3.7–10.1], p < 0.01) in the proximal tibia, extrapolation by correlation analysis showed no clinically relevant difference between the sexes. Conclusion: In adults, there are no sex-specific differences in the appropriate insertion depth for intraosseous access in the proximal or distal tibia or in the proximal humerus.

Objectives: Injuries on alpine ski slopes have been described in cohorts of a reasonable sample size, but constant improvements in safety gear, increased use of airborne rescue, and safety measures during the coronavirus disease 2019 (COVID-19) pandemic mandate re-evaluation. Therefore, the purpose of this study was to evaluate skiing and snowboarding injuries, effectiveness of airborne rescue, and impact of the COVID-19 pandemic on a large sample size. Methods: Data on alpine injuries were prospectively collected from the state emergency services dispatch center in the state of Tyrol (Austria). A total of 10,143 patients were identified, with an average age of 33.5 years (SD = 20.36). The ski patrol was involved in 8,606 cases (84.9%) and some patients (n = 1,536; 15.1%) required helicopter rescue. Results: A total of 10,143 patients were identified from the dataset of the emergency dispatch center. The most frequently injured region was the knee (30.2%), and it was followed by the shoulder (12.9%), the lower leg (9.5%), and the head/skull (9.5%). Conclusion: The present findings indicate that the most frequent site of injuries on alpine slopes is the knee, and life-threatening injuries are rare. Airborne rescue is very time-effective, however clinical studies with patient follow-up should be emphasized to determine the impact of airborne rescue on patient outcome. The present findings indicate that the duration of all rescue operations has been prolonged as a result of the introduction of safety measures during the COVID-19 pandemic.

Primary total hip arthroplasty with cementless stems has numerous advantages over cemented total hip arthroplasty in patients with good bone quality. To enhance osseointegration with ingrowth into the implant, various surface treatments have been proposed. Multiple biomechanical studies in animals have shown that bioactive coatings enhance osseointegration and increase construct stability. Bony ingrowth in humans can only be assessed in rare instances of periprosthetic femoral fractures. In this case report, we describe the findings after a periprosthetic fracture mandating stem exchange in a patient who experienced a fall 8 weeks after implantation. The retrieved proximal Bonit (DOT GmbH, Rostock, Germany) coated stem showed substantial macroscopically visible trabecular bone. This finding supports results from animal studies that showed enhanced metaphyseal bone ingrowth with Bonit coating of implants.

BACKGROUND:Shorter double-taper stems with reduced lateral shoulders facilitate implantation via the muscle-sparing direct anterior approach and are becoming increasingly popular. We observed an unusually high number of cases of aseptic loosening with the use of a modified stem. Therefore, the aim of this prospective single-center study was to assess safety and efficacy of this cementless stem. METHODS:A total of 486 consecutive patients receiving 517 primary total hip arthroplasties using the MonoconMIS stem were prospectively followed up for a mean period of 5.29 years (standard deviation [SD], 1.47). Surgical and clinical data, complications, and revision surgeries were analyzed. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) score was recorded before surgery and at one year and five years after surgery. RESULTS:The overall 5-year implant survival rate was 95.2%. The individual component survival rates were 96.1% for the stem, 99.4% for the acetabular cup, and 99.0% for the isolated mobile component exchange. The most common reasons for revision were periprosthetic fracture (1.5%), aseptic stem loosening (1.4%), and infection (1.0%). The WOMAC score improved significantly from 49.57 (SD, 21.42) at baseline to 13.33 (SD, 16.47) at one year and 9.84 (SD, 14.45) at five years after surgery. Aseptic stem loosening occurred only in patients with Dorr type A proximal femur morphology. CONCLUSION:The evaluated femoral stem is associated with revision rates higher than what has been reported for other implants. The WOMAC scores suggest adequate efficacy. Our data do not support the use of the MonoconMIS for primary total hip arthroplasty in patients with Dorr type A proximal femur morphology.

The aim of the study was to investigate the issue of medial midvastus (MMV) vs. medial parapatellar (MPP) approaches in total knee arthroplasty (TKA). It was hypothesized that the two surgical approaches would produce significantly different results with respect to patient-reported knee score outcome (hypothesis 1), short-term postoperative range of motion (ROM) (hypothesis 2), long-term postoperative ROM (hypothesis 3) and prosthesis survival (hypothesis 4). A retrospective comparative study design was applied. Data sets were obtained from the state arthroplasty registry. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC) data were analyzed from preoperative and 1 year postoperatively. The ROM data were analyzed for the time points preoperative, postoperative days 4 and 10 and 1 year. Available were 627 cases (407 MMV vs. 220 MPP) and 1 year postoperatively there were no significant differences between groups regarding the WOMAC scores (hypothesis 1). Early postoperatively on days 4 and 10 after TKA there were no differences between groups (p = 0.305 and p = 0.383, respectively, hypothesis 2). Likewise, ROM did not significantly differ between the groups 1 year after TKA (p = 0.338, hypothesis 3). The 5‑year prosthesis survival did not differ between the groups and showed 94.46% (95% confidence interval, CI 90.69–96.73%) in the MMV group and 94.33% (95% CI 89.96–96.83%) in the MPP group (p = 0.664, hypothesis 4). Both surgical approaches produce equivalent clinical results in terms of early postoperative ROM, late postoperative ROM and 1‑year WOMAC. The same prosthesis survival rates can be expected.