Aims: The present study investigated the five-year interval changes in pseudotumours and measured serum metal ions at long-term follow-up of a previous report of 28 mm diameter metal-on-metal (MoM) total hip arthroplasty (THA). Patients and Methods: A total of 72 patients (mean age 46.6 years (37 to 55); 43 men, 29 women; 91 hips) who underwent cementless primary MoM THA with a 28 mm modular head were included. The mean follow-up duration was 20.3 years (18 to 24). All patients had CT scans at a mean 15.1 years (13 to 19) after the index operation and subsequent follow-up at a mean of 20.2 years (18 to 24). Pseudotumour volume, type of mass, and new-onset pseudotumours were evaluated using CT scanning. Clinical outcomes were assessed by Harris Hip Score (HHS) and the presence of groin pain. Serum metal ion (cobalt (Co) and chromium (Cr)) levels were measured at the latest follow-up. Results: At final follow-up, pseudotumours were observed in 26/91 hips (28.6%). There was an increase in volume of the pseudotumour in four hips (15.4%), no change in volume in 21 hips (80.8%), and a decrease in volume in one hip (3.8%). There were no new-onset pseudotumours. There was no significant difference in HHS between patients with and without pseudotumours. At final follow-up, mean serum Co ion levels and median Co:Cr ratios were significantly greater in patients with pseudotumours, but the serum Cr ion levels were not significantly different. Conclusion: At a mean 20 years of follow-up, pseudotumours were observed in 26/91 hips (28.6%) with no new-onset pseudotumours during subsequent follow-up. Most pseudotumours in small-head MoM THA were static in volume and asymptomatic with normal serum metal ion levels. Cite this article: Bone Joint J 2019;101-B:317–324.

Background: This study aimed to assess the reproducibility and reliability of Chat-Based GPT (ChatGPT)’s responses to 19 statements regarding the management of hip fractures in older adults as adopted by the American Academy of Orthopaedic Surgeons’ (AAOS) evidence-based clinical practice guidelines. Methods: Nineteen statements were obtained from the 2021 AAOS evidence-based clinical practice guidelines. After generating questions based on these 19 statements, we set a prompt for both the GPT-4o and GPT-4 models. We repeated this process three times at 24 h intervals for both models, producing outputs A, B, and C. ChatGPT’s performance, the intra-ChatGPT reliability, and the accuracy rates were assessed to evaluate the reproducibility and reliability of the hip fracture-related guidelines. Regarding the strengths of the recommendation compared with the 2021 AAOS guidelines, we observed accuracy of 0.684, 0.579, and 0.632 for outputs A, B, and C, respectively. Results: The precision was 0.740, 0.737, and 0.718 in outputs A, B, and C, respectively. For the reliability of the strengths of the recommendation, the Fleiss kappa was 0.409, indicating a moderate level of agreement. No statistical differences in the strengths of the recommendation were observed in outputs A, B, and C between the GPT-4o and GPT-4 versions. Conclusion: ChatGPT may be useful in providing guidelines for hip fractures but performs poorly in terms of accuracy and precision. However, hallucinations remain an unresolved limitation associated with using ChatGPT to search for hip fracture guidelines. The effective utilization of ChatGPT as a patient education tool for the management of hip fractures should be addressed in the future.

Oxidised regenerative cellulose (ORC) is an absorbable haemostatic agent that acts independently on the blood coagulation mechanisms. Although ORC products have been used as adjuncts in various surgical procedures, their haemostatic effect, particularly the powder type (Surgicel®-P), during primary total hip arthroplasty (THA) remains uncertain. This study aimed to evaluate the effectiveness and safety of ORC powder in patients undergoing primary THA. This study included 279 patients who underwent primary THA between January 2022 and July 2024, and they were divided into two groups based on the use of ORC powder: the control (n = 138) and SC (SurgiCel group, n = 141) groups. Data on perioperative outcomes, including operative time, total blood loss (TBL), intraoperative blood loss (IBL), hidden blood loss (HBL), haemoglobin (Hb) drops, and complication rates over 3 months, were collected and compared between the two groups. The mean IBL was significantly lower in the SC group (197.1 mL) than in the control group (243.5 mL) (P < 0.001). The total operative time (P = 0.465), procedure time (P = 0.117), TBL (P = 0.167), and HBL (P = 0.771) showed no significant differences. The mean postoperative Hb drop was significantly different between the control and SC groups (1.5 vs. 1.0 g/dL, P < 0.001). Similarly, the mean postoperative day 1 Hb drop was significantly lower in the SC group than in the control group (1.7 vs. 2.0 g/dL, P = 0.013). Complication rates showed no significant differences during the 3-month postoperative follow-up. ORC powder significantly reduced IBL and postoperative Hb drops without any comparable complications in patients undergoing primary THA. These findings suggest that ORC powder is a safe and effective haemostatic agent during primary THA procedures, which may be a valuable adjuvant for reducing blood loss and potential to reduce blood transfusion requirements.