Prediction of Footplate Position after Implantable Collamer Lens Implantation Based on Iris and Ciliary Body Morphologies.

PURPOSE: To investigate the factors affecting footplate position and its influence on vault characteristics following implantable collamer lens (ICL) implantation. SETTING: Hunan Provincial People's Hospital, Changsha, China. DESIGN: Retrospective case series. METHODS: This study included 124 patients (124 eyes). Ultrasound biomicroscopy (UBM) was performed to assess the iris and ciliary body morphologies and observe the footplate position. Using multiple linear regression, the relationship between various ocular and ICL parameters and the vault as well as the factors affecting the footplate distance (FD) were analyzed. Based on the FD, three groups were formed: group 1 (<500 µm), group 2 (500-1000 µm), and group 3 (>1000 µm). The distribution of the vault range after surgery was observed for the three groups. RESULTS: Ciliary sulcus angle and FD significantly impacted the vault (adjusted R2=0.190, F=6.763, P<0.001), with FD being the most important factor influencing the vault (Beta=-0.383, P<0.001). Postoperative UBM revealed that the footplate was located at different positions in the posterior chamber, with the majority (52%) being located on the ciliary body. The average size of the four footplate orientations was 0.88±0.24 mm. Multiple linear regression analysis revealed that ciliary body thickness (CBT), iris curvature (IC), and ICL iris contact length (IRCL) significantly influenced the FD (adjusted R2=0.373, F=11.432, P<0.001). The vault range differed significantly among the three groups (X2=32.33, P<0.001). CONCLUSIONS: Different postoperative ICL footplate positions significantly affect the vault. CBT, IC, and IRCL can alter the position of the footplate from the expected position. This study provides reference for ICL size selection and vault prediction.

Risk-Stratified Venous Thromboembolism Prophylaxis after Total Joint Arthroplasty: Low Molecular Weight Heparins and Sequential Aspirin vs Aggressive Chemoprophylaxis.

OBJECTIVE: Venous thromboembolism (VTE) is a significant concern post total joint arthroplasty (TJA). However, the optimal prevention method of VTE remains controversial at present. This study aims to evaluate a risk-stratified VTE prophylaxis protocol for patients undergoing TJA. METHODS: A total of 891 TJA patients from January 2011 to November 2019 were retrospectively investigated. The study was divided into two cohorts. In cohort 1, 410 patients (250 females and 160 males, mean age 64.32 years) were treated with an aggressive VTE chemoprophylaxis protocol. In cohort 2, 481 patients were treated with a risk-stratified protocol that utilized low molecular weight heparins (LMWH) and sequential aspirin (ASA) for standard-risk patients (a total of 288 containing 177 females and 111 males, mean age 65.4 years), and targeted anticoagulation for high-risk patients (a total of 193 containing 121 females and 72 males, mean age 66.8 years). The patients were followed up at 2-4 weeks for an initial visit and at 6-10 weeks for a subsequent visit after surgery. A chart review of all patient medical records was performed to record the demographics, comorbidities, deep vein thrombosis, pulmonary embolus, superficial infection, deep infection, bleeding complications, and 90-day readmissions. RESULTS: The VTE rate was 1.71% (7/410) in cohort 1 and 1.46% (7/481) in cohort 2 respectively. For cohort 2, the VTE rate was 2.07% (4/193) in high-risk group and 1.04% (3/288) in standard-risk group. The readmission rate was 2.44% (10/410) in cohort 1 and 2.08% (10/481) in cohort 2. For cohort 2, the readmission rate was 2.07% (4/193) in high-risk group and 2.08% (6/288) in standard-risk group. The reasons for readmission were as follows: infection, 1.3% (5/410) in cohort 1 and 1.3% (6/481) in cohort 2; wound or bleeding complications, 0.48% (2/410) in cohort 1 and 0.2% (1/481) in cohort 2; trauma, 0.2% (1/410) in cohort 1 and 0.2% (1/481) in cohort 2; VTE, 0.2% (1/410) in cohort 1 and 0.2% (1/481) in cohort 2; others, 0.2% (1/410) in cohort 1 and 0.6% (3/481) in cohort 2. There was a decrease in VTE events and readmissions in the risk-stratified cohort, although this did not reach statistical significance. However, it was found that there was a significant reduction in costs (P < 0.001) with the use of LMWH/ASA, when compared with aggressive anticoagulation agents in the risk-stratified cohort. CONCLUSION: The use of LMWH/ASA in a risk-stratified TJA population is a safe and cost-effective method of VTE prophylaxis.

Usefulness of a Simple Preoperative Planning Technique using Plain X-rays for Direct Anterior Approach for Total Hip Arthroplasty.

OBJECTIVE: To examine the accuracy, reliability, and reproducibility of a simple preoperative planning technique using plain X-rays. METHODS: A retrospective analysis of 96 consecutive cases of primary direct anterior approach (DAA)-total hip arthroplasty (THA) from July 2015 to December 2018 was performed. The 96 patients included 24 males and 72 females, with an average age of 70 years. The standard AP pelvis radiographs with the patients' hips extended and internally rotated were obtained pre- and postoperatively. The preoperative planning was also completed on the standardized AP pelvic radiographs. The prearranged cup positioning was radiologically measured intraoperatively using fluoroscopy. The correct leg length was assessed intraoperatively, which was compared with the preoperative planning. The component positioning was measured by three independent researchers. Two of the researchers completed the measurements three times, and intra-observer and inter-observer reliability were calculated. All patients received at least 6 months follow-up (6 months-4 years). RESULTS: In all cases, the median leg length discrepancy (LLD) was 4.4 mm (range 1.6-15.9 mm), and 84 patients had an LLD smaller than 10 mm, of which 58 patients had an LLD of less than 5 mm. None of the patients had a critical LLD of 2 cm or larger. The multivariable logistic regression for LLD (safe range: yes/no) with the co-variables including gender, ASA classification, type of cup, the surgeon's experience level, and the presence of a total hip arthroplasty (THA) on the contralateral side did not present statistical significance. The median angle of the inclination of the acetabular component (IA) was 42.3° (range: 28.7°-52.2°). Ninety-one patients were within the defined safe range. The hit ratio for the cup to be within the safe zone was significantly higher for the Pinnacle cups than that for the Continuum cups (P < 0.05). However, there was no significant difference in gender, ASA classification, the surgeon's experience level, and the presence of a total hip arthroplasty (THA) on the contralateral side. The median of its anteversion (AA) was 20.6° (range: 10.6°-40.1°). Only 41 patients were within the defined safe range. None of the co-variables presented a statistical significance affecting the AA of the cup positioning. Meanwhile, the average fluoroscopy time for the cup positioning (n = 86, missing data in 10 cases) was 4 seconds (range: 1-74), with most of the patients (97.9%) having a fluoroscopy time of fewer than 20 seconds. CONCLUSIONS: The combination of correct preoperative planning and standardized intraoperative measurements can reestablish right leg length and assure the correct cup positioning.