OBJECTIVE: To summarize research progress on enhanced recovery after posterior cruciate ligament (PCL) reconstruction, clarify the core contradictions, effective intervention methods, and evaluation shortcomings in current clinical practice, and provide theoretical support for optimizing clinical rehabilitation strategies. METHODS: Relevant domestic and international literature in recent years was systematically searched. The key technologies and challenges for enhanced recovery after PCL reconstruction were analyzed from three aspects: the core issues of enhanced recovery after PCL reconstruction, treatment strategies, and the post-reconstruction effectiveness evaluation system. RESULTS: Enhanced recovery after PCL reconstruction mainly faces two core problems. First, there is a balance dilemma between graft tendon protection and knee joint function recovery: the tensile capacity of the graft tendon is weak in the early postoperative period, so excessive weight-bearing easily leads to relaxation, while overly conservative immobilization causes muscle atrophy and joint adhesion. Second, the return-to-sport rate is significantly affected by injury type and treatment method: patients with combined multiple ligament or meniscus injuries have a much lower return-to-sport rate than those with isolated PCL injury, and the risk of return-to-sport failure is higher. Current research mainly promotes rehabilitation from two aspects: physical therapy and surgical technology. Physical therapy runs through the perioperative period: preoperatively, muscle strength training, swelling control, and maintenance of joint range of motion are used to optimize surgical conditions; postoperatively, phased intervention is implemented. Surgical technology focuses on minimally invasive and anatomical approaches: arthroscopic surgery reduces injury, double-bundle reconstruction and internal tension-relief technology improve stability, and modified tunnel positioning and special surgical methods avoid the risk of "Killer Turn". Postoperative functional evaluation adopts multi-dimensional indicators: subjective evaluation relies on scales such as Lysholm and International Knee Documentation Committee (IKDC); objective evaluation assesses stability through Telos stress test and posterior drawer test; imaging evaluation takes MRI as the core; psychological evaluation is assisted by the Tampa scale of kinesiophobia-11 (TSK-11). However, there are obvious shortcomings, such as the lack of PCL-specific evaluation tools. CONCLUSION Enhanced recovery after PCL reconstruction requires the integration of precise surgery, individualized rehabilitation, and comprehensive subjective and objective evaluation. In the future, biomaterials and digital technologies should be integrated to optimize the full-cycle management of PCL reconstruction, thereby improving functional recovery and the effect of return to sports.
Humans ; Posterior Cruciate Ligament Reconstruction/rehabilitation* ; Posterior Cruciate Ligament/injuries* ; Recovery of Function ; Knee Joint/physiopathology* ; Knee Injuries/rehabilitation* ; Return to Sport ; Enhanced Recovery After Surgery ; Tendons/transplantation* ; Arthroscopy

In recent years,China has made great progress in basic nanomedicine,nanotoxicology and nanobiology research.Nanotechnology has been continuously applied in biomaterial and medical device,more and more medical devices applying nanomaterials are developed and manufactured.In order to gain more comprehension and accurate understanding of the research and industrial development in nanobiomaterial medical devices,this study reviewed the common nanomaterial in medical devices and the regulatory situation of nanomaterial medical devices at home and abroad,and discussed the current challenges in biological evaluation of nanomaterial medical devices,with a view to providing ideas for the safety evaluation and research of related products.

BACKGROUND: Extreme temperature events, including extreme cold, are becoming more frequent worldwide, which might be harmful to pregnant women and cause adverse birth outcomes. We aimed to investigate the association between exposure to low ambient temperature in pregnant women and adverse birth outcomes, such as preterm birth, low birth weight, and stillbirth, and to summarize the evidence herein. METHODS: Relevant studies were searched in PubMed, Cochrane, and Embase electronic databases until November 2021. Studies involving low ambient temperature, preterm birth, birth weight, and stillbirth were included. The guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses were followed to conduct this study risk of bias and methods for data synthesis. RESULTS: A total of 34 studies were included. First, pregnant women exposed to low ambient temperature had an increased risk of preterm birth (risk ratio [RR] 1.08; 95% confidence interval [CI] 1.04-1.13). Subgroup analyses revealed that exposure during late pregnancy was more likely to induce preterm birth. In addition, only pregnant women exposed to <1st percentile of the mean temperature suffered increased risk of preterm birth. Moreover, pregnant women living in medium or hot areas were more prone to have preterm births than those in cold areas when exposed to low ambient temperatures. Asians and Blacks were more susceptible to low ambient temperatures than Caucasians. Second, pregnant women exposed to low ambient temperature had an increased risk of low birth weight (RR 1.07; 95% CI 1.03-1.12). Third, pregnant women had an increased risk of stillbirth while exposed to low ambient temperature during the entire pregnancy (RR 4.63; 95% CI 3.99-5.38). CONCLUSIONS: Exposure to low ambient temperature during pregnancy increases the risk of adverse birth outcomes. Pregnant women should avoid exposure to extremely low ambient temperature (<1st percentile of the mean temperature), especially in their late pregnancy. This study could provide clues for preventing adverse outcomes from meteorological factors. REGISTRATION No. CRD42021259776 at PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ ).
Pregnancy ; Infant, Newborn ; Female ; Humans ; Pregnancy Outcome ; Premature Birth/epidemiology* ; Stillbirth/epidemiology* ; Temperature ; Pregnancy Complications