Background: The Footscan® platform system is one of the most commonly used clinical tools for the measurement of the foot pressure. The present study was designed to assess the repeatability of the system and identify the range of loading parameters observed in the normal foot.Methods: Measurements were collected from 32 healthy participants, 15 females and 17 males, twice at an interval of 1 week. Peak pressure (PP), contact time (CT), contact area (CA), pressure‐time integral (PTI), and maximum force (MaF) were recorded; these parameters were investigated in 10 areas of the foot: medial heel, lateral heel, midfoot, first to fifth metatarsals, hallux, and toes 2–5. The intra‐session repeatability was evaluated by calculating the intraclass correlation coefficients (ICCs) and coefficients of variation (CVs) across the three repeated trials within the same session. The inter‐session repeatability was assessed using the average of the three trials in each session to determine the ICCs and CVs.Results: The ICCs showed moderate to good repeatability for every variable of interest, and the CVs were all <28%. The highest zones of PP were found under the second and third metatarsals, followed by the medial heel. The CT was 68.5–82.8% of the total stance time under the metatarsal heads. CA was highest under the midfoot, PTI was highest under the second metatarsal, and MaF was highest under the medial heel.Conclusions: Footscan® platform system was found to be repeatable. Thus, it can be used as a valuable tool in the assessment of plantar pressure distribution, and the normal values of the foot loading parameters identified in this study can be employed to provide a reference range for the gait analysis performed by the Footscan® system.

Large Language Models (LLMs) such as ChatGPT-4.0 and DeepSeek-R1 provide advanced natural language capabilities, but they also raise concerns regarding accuracy in medical applications. There is a lack of systematic evaluation of their performance against orthopedic guidelines, particularly for knee osteoarthritis (KOA). This study assessed the accuracy and consistency of these LLMs in relation to the most recent Chinese clinical practice guidelines for KOA. Queries regarding 17 guideline-recommended KOA therapeutic strategies were posed to ChatGPT-4.0 and DeepSeek-R1. Two independent reviewers evaluated response concordance (Concordance, Discordance, or No Concordance) with guidelines. Inter-rater reliability was assessed using Cohen's kappa coefficient. A chi-square test was employed to compare the response patterns between the two models. ChatGPT-4.0 showed 59 % concordance; DeepSeek-R1 achieved 71 %. Both models gave inconsistent recommendations for ozone therapy and arthroscopy. ChatGPT-4.0 had five inconsistent responses; DeepSeek-R1 had three. Inter-rater agreement was high (κ = 0.90 and 0.86). No significant difference was found in concordance rates (P = 0.7; P = 1). Only DeepSeek-R1 provided references (38 in total), but just 8 were fully verifiable. Neither ChatGPT-4.0 nor DeepSeek-R1 consistently produced responses aligned with evidence-based clinical guidelines. These findings highlight the need for cautious interpretation of medical advice generated by current AI platforms, both by clinicians and patients.

As cortical bone has a hierarchical structure, the macroscopic bone strength may be affected by the alterations of mineral crystal and collagen, which are main components of cortical bone. Limited studies focused on the time related alterations of these two components in osteoporosis, and their contributions to bone mechanics at tissue level and whole-bone level. Therefore, the purpose of this study was to elucidate the time related changes of mineral and collagen in cortical bone of ovariectomized (OVX) rabbits, and to relate these changes to cortical bone nanomechanics and macromechanics. 40 Rabbits (7-month-old) were randomly allocated into two groups (OVX and sham). OVX group received bilateral ovariectomy operation. Sham group received sham-OVX operation. Cortical bone quality of five rabbits in each group were assessed by DXA, μCT, nanoindentation, Fourier transform infrared (FTIR) spectroscopy and biomechanical tests (3-point bending of femoral midshaft) at pre-OVX, 4, 6, and 8 weeks after OVX. As time increased from pre-OVX to 8 weeks, the mineral to matrix ratio decreased with time, while both collagen crosslink ratio and crystallinity increased with time in OVX group. Elastic modulus and hardness measured by nanoindentation, whole-bone strength measured by biomechanical tests all decreased in OVX group with time. Bone material properties measured by FTIR correlated well with nano or whole-bone level mechanics. However, bone mineral density (BMD), structure, tissue-level and whole-bone mechanical properties did not change with age in sham group. Our study demonstrated that OVX could affect the tissue-level mechanics and bone strength of cortical bone. And this influence was attributed to the time related alterations of mineral and collagen properties, which may help us to design earlier interventions and more effective treatment strategies on osteoporosis.

The Footscan platform is a useful tool for plantar pressure measurement. However, there is still controversy over whether or not the platform should be covered by top-layer during the test. This study was designed to compare the reliability of the Footscan platform and identify the differences of the foot loading parameters between without top-layer (WOT) and with top-layer (WT) protocols. Measurements were taken from thirty-two healthy subjects. Participants were tested with a Footscan platform using the WOT and WT protocols. Three trials were performed during two separate testing sessions with a 7-day interval. Peak pressure, contact time, contact area, and pressure-time integral at ten foot zones were recorded and calculated for intra- and intersession reliability using intraclass correlation coefficients (ICCs) and coefficients of variation (CVs). The reliability and values of the analyzed parameters for the two protocols were compared. Both protocols produced a moderate to good level of intra- and intersession reliability. Compared with the WT protocol, the WOT protocol showed higher ICCs, lower CVs, and higher values in most of the parameters analyzed. The results suggest that the WOT protocol showed better reliability than the WT protocol. We recommend not using the top-layer when performing the plantar pressure test.

This study was aimed at elucidating the temporal changes of microarchitectural and mechanical parameters of cancellous bone in the osteoporotic rabbit model induced by ovariectomy (OVX) combined with glucocorticoid (GC) administration. Osteoporotic (OP) group received bilateral OVX combined with injections of GC, while sham group only received sham operation. Cancellous bone quality in vertebrae and femoral condyles in each group was assessed by DXA,μCT, nanoindentation, and biomechanical tests at pre-OVX and 4, 6, and 8 weeks after injection. With regard to femoral condyles, nanoindentation test could detect significant decline in tissue modulus and hardness at 4 weeks. However, BMD and microarchitecture of femoral condylar cancellous bone changed significantly at 6 weeks. In vertebrae, BMD, microarchitecture, nanoindentation, and biomechanical tests changed significantly at 4 weeks. Our data demonstrated that temporal changes of microarchitectural and mechanical parameters of cancellous bone in the osteoporotic rabbit were significant. The temporal changes of cancellous bone in different anatomical sites might be different. The nanoindentation method could detect the changes of bone quality at an earlier stage at both femoral condyle and vertebra in the osteoporotic rabbit model than other methods (μCT, BMD).

Background: Total knee arthroplasty (TKA) is a surgical procedure primarily used to treat patients with end-stage knee osteoarthritis (KOA). Postoperative physical exercise is a critical part of the overall treatment of KOA and can bring significant benefits to the patients' recovery. Wearable devices can monitor patients' exercise data and upload it to the physician's workstation. This allows the rehabilitation physician to make timely adjustments based on the patients' movement feedback, and the surgeon can be informed of the patients' functional status. Overall, this study aims to evaluate the effectiveness of using wearable monitoring devices for rehabilitation exercise after TKA, with a focus on cost, time savings, and patient outcomes. Method/design: This is a single-center, single-blinded, parallel randomized controlled trial conducted at Xi'an Honghui Hospital, a regional orthopedic medical center. Eligible patients will be recruited to participate in the study, and baseline data collection and clinical assessments will be conducted at the time of admission. Using the principle of random allocation, recruited patients will be divided into either the experimental or control group. Both groups will undergo a standard, widely promoted rehabilitation program. The patients in the experimental group will wear equipment to detect and track mobility in the lower limbs. All patients will return to the outpatient clinic for follow-up assessments at 2 weeks, 12 weeks, and 24 weeks after discharge, where outcome indicators will be measured. The primary outcome will be the cost and time after discharge, while secondary outcomes will include the 6-min walk test (6MWT), range of motion (ROM), visual analog scale (VAS), American Knee Society Score (KSS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Discussion: We should encourage the adoption of novel, easy-to-use, supervised devices if they prove to be beneficial for patients in terms of cost, time, and effectiveness after TKA. This type of device is particularly important for people in remote rural areas, those with limited financial resources, and those who are reluctant to return to hospitals for follow-up care. Trial registration Chinese Clinical Trial Registry ChiCTR2300068418. Registered on 17 February 2023.