Total shoulder arthroplasty in France: An analysis of trends between 2009 and 2019 and projections to the year 2070.

BACKGROUND: Over the past decades, total shoulder arthroplasty (TSA) procedures have steadily increased in the United States and Europe. In France, the number of shoulder surgeries rose by 24.5% between 2012 and 2018, but no study has yet analyzed TSA trends based on patient characteristics. Therefore, the aim of our study was to use the French healthcare database to (1) analyze growth trends based on the patient's sex, age, and comorbidity profile and (2) estimate the most appropriate incidence rate (IR) projections to the year 2070. HYPOTHESIS: We hypothesize that in France, the upward trends are different for each sex and age group. MATERIALS AND METHODS: This study was conducted in France from 2009 to 2019 based on the French healthcare database (SNDS), which contains all nationwide procedures. Patients were analyzed by sex, age group (<65 years, 65-74 years, ≥75 years), and comorbidity profile (4 levels). IR trends per 100,000 population were inferred by patient age, sex, and comorbidity using data from the French hospital discharge database (PMSI) and population forecasts and censuses from the French National Institute of Statistics and Economic Studies (INSEE). Linear, Poisson, logistic, and Gompertz projection models were created to forecast IRs to the year 2070. RESULTS: Between 2009 and 2019, there was a sharper increase in IR in males (+155%; from 6.0 to 15.3) than in females (+118%; from 16.2 to 35.3) across all age groups. This increase was most significant in those younger than 65 years (+112%; from 2.3 to 4.9), in both males (+129%; from 2.1 to 4.8) and females (+99%; from 2.5 to 5.0). From 2012 to 2019, the proportion of patients with mild comorbidities increased by +92% (from 5,435 to 10,410 TSAs, i.e., from 56% to 61% of total procedures), unlike the other comorbidity profiles. All the projections modeled the data from 2009 to 2019 with minor deviations. However, the logistic projection was the most likely, with a 45% increase in the IR for the overall population by 2070 (from 17,175 to 25,338 TSAs), which will start to plateau in 2050. CONCLUSION: The IR has risen sharply in the overall population, as in all age, sex, and comorbidity categories, with the most significant growth seen in the<65 and 65-74 age groups and a shift toward patients with milder comorbidities. According to our projections, the IR will continue to be more significant in older patients, except for males, for whom the IR for those 65 to 74 years old will exceed that of those 75 and older around 2030. In the longer term, the IRs follow a logistic trend, reaching a plateau around 2050. Therefore, an increase in healthcare burden is to be expected to meet the growing demand for TSAs. LEVEL OF EVIDENCE: IV; Descriptive epidemiological study.

Functional safe zone for THA considering the patient-specific pelvic tilts: An ultrasound-based approach.

The usual Lewinnek orientation for cup positioning in total hip arthroplasty is not suitable for all patients as it does not consider the patient mobility. We propose an ultrasound-based approach to compute a Functional Safe Zone (FSZ) considering daily positions. Our goal was to validate it, and to evaluate how the input parameters impact the FSZ size and barycentre. The accuracy of the FSZ was first assessed by comparing the FSZ computed by the proposed approach and the true FSZ determined by 3D modelling. Then, the input parameters' impact on the FSZ was studied using a principal component analysis. The FSZ was estimated with errors below 0.5° for mean anteversion, mean inclination, and at edges. The pelvic tilts and the neck orientation were found correlated to the FSZ mean orientation, and the target ROM and the prosthesis dimensions to the FSZ size. Integrated into the clinical workflow, this non-ionising approach can be used to easily determine an optimal patient-specific cup orientation minimising the risks of dislocation.

Anterior pelvic plane estimation for total hip arthroplasty using a joint ultrasound and statistical shape model based approach.

Orienting properly the prosthetic cup in total hip arthroplasty is key to ensure the postoperative stability. Several navigation solutions have been developed to assist surgeons in orienting the cup regarding the anterior pelvic plane (APP), defined by both anterior superior iliac spines (ASIS) and the pubic symphysis. However acquiring the APP when the patient is ready for surgery, i.e., mainly in lateral decubitus, is difficult due to the contralateral ASIS being against the operating table. We propose a method to determine the APP from both (1) alternative anatomical landmarks which are easy to acquire with a navigated ultrasound probe and (2) a Statistical Shape Model (SSM) of the pelvis. After creating a pelvic SSM from 40 data, a SSM-based morphometric analysis has been carried out to identify the best anatomical landmarks allowing the easy determination of the APP. The proposed method has then been assessed with both in silico and in vivo experiments on respectively forty synthetic data, and five healthy volunteers. The in silico experiment shows the feasibility to determine the APP with an average error of 4.7∘ by only acquiring the iliac crest, the anterior superior iliac spine, the anterior inferior iliac spine, and the pubic symphysis. The average in vivo error using the ultrasound modality was 7.3∘ with an estimated impact on both the cup anteversion and inclination of 4.0∘ and 1.7∘ respectively. The proposed method shows promising results that could allow the determination of the APP in lateral decubitus with a clinically acceptable impact on the computation of the cup orientation.

Statistical Shape Modeling to Determine the Anterior Pelvic Plane for Total Hip Arthroplasty.

The anterior pelvic plane (APP) defined by both iliac spines and the pubic symphysis, is essential in total hip arthroplasty (THA) for the orientation of the prosthetic cup. However, the APP is nowadays still difficult to determine in computer assisted orthopedic surgery (CAOS). We propose to use a statistical shape model (SSM) of the pelvis to estimate the APP from ipsilateral anatomical landmarks, more easily accessible during surgery in computer assisted THA with the patient in lateral decubitus position. A SSM of the pelvis has been built from 40 male pelvises. Various ipsilateral anatomical landmarks have been extracted from these data and used to deform the SSM. Fitting the SSM to several combinations of these landmarks, we were able to reconstruct the pelvis with an accuracy between 2.8mm and 4.4mm, and estimate the APP inclination with an angular error between 1.3° and 2.8°, depending on the landmarks fitted. Results are promising and show that the APP could be acquired during the intervention from ipsilateral landmarks only.

Accuracy and Precision of an Ultrasound-Based Device to Measure the Pelvic Tilt in Several Positions.

OBJECTIVES: A new ultrasound-based device is proposed to measure the patient-specific pelvic tilt in different daily positions. The aim of this study was to assess the accuracy of this device as well as the intraobserver and interobserver precisions. METHODS: The accuracy was assessed by performing several tilt measurements with the device on a testing mechanical bench. The error was defined as the difference between the tilt measured with the device and the tilt provided by this test bench. Three physicians, a novice, an intermediate, and an expert user, were also asked to perform 10 measurements on 3 healthy volunteers with low, medium, and high body mass indices to analyze the intraobserver and interobserver precisions. These 10 measurements were performed in the standing, sitting, and supine positions. RESULTS: The mean accuracy of the device ± SD was 1.1° ± 0.7° (range, 0°-4.0°). The interobserver and intraobserver precisions were excellent whatever the body mass index and good to excellent according to the positions. There was no learning curve, and the time required to complete the measurements was approximately 5 minutes. CONCLUSIONS: This study presents an accurate and precise noninvasive device for measurement of the pelvic tilt in different positions.