Aging leads to a decline in skin function due to intrinsic factors (genetics, hormones) and extrinsic factors (sun exposure, pollutants). Type I collagen plays a vital role in maintaining skin integrity and elasticity. As aging progresses, collagen synthesis diminishes, resulting in weakened skin structure and wrinkle formation. This systematic review explores the role of type I collagen in skin aging by summarizing key clinical findings. A systematic search was conducted using PubMed and ScienceDirect as the primary databases, including studies published between 2014 and 2025 that addressed type I collagen and skin aging. Eleven clinical studies were selected following PRISMA guidelines. The results consistently show the decline of type I collagen as a central contributor to dermal thinning, loss of elasticity, and the appearance of wrinkles and sagging. Clinical trials demonstrate that collagen supplementation, particularly from hydrolyzed fish cartilage and low-molecular-weight peptides, enhances collagen production, improves skin hydration and texture, and reduces signs of photoaging. Overall, the evidence emphasizes the critical role of type I collagen in skin aging and suggests that targeted collagen supplementation may serve as an effective strategy to maintain skin structure and combat visible signs of aging.

Introduction: Despite significant advancements in total knee arthroplasty (TKA), some patients require revision surgery (R‐TKA) due to complications such as infection, mechanical loosening, instability, periprosthetic fractures, and persistent pain. This study aimed to explore the specific causes leading to R‐TKA, associated complications, including infection, mechanical failure, and wound issues, as well as costs, mortality rates, and hospital length of stay (LOS) using data from a large national database.Methods: Data from the nationwide inpatient sample (NIS), the largest publicly available all‐payer inpatient care database in the United States were analysed from 1 January 2016 to 31 December 2019. The study included 44,649 R‐TKA cases, corresponding to 223,240 patients, with exclusions for nonelective admissions. Various statistical analyses were used to assess clinical outcomes, including in‐hospital mortality, postoperative complications, LOS, and hospitalization costs.Results: Among 2,636,880 TKA patients, 8.4% underwent R‐TKA. R‐TKA patients had higher rates of chronic conditions, including mental disorders (36.4%) and renal disease (9.9%). Additionally, these patients often experienced instability, necessitating revision surgery. Infection (22.3%) was the primary reason for R‐TKA, followed by mechanical loosening (22.9%) and instability. Compared to primary TKA patients, R‐TKA patients exhibited higher in‐hospital mortality (0.085% vs. 0.025%), longer LOS (3.1 vs. 2.28 days), and higher total charges ($97,815 vs. $62,188). Postoperative complications, including blood transfusion (4.6% vs. 1.3%), acute kidney injury (4.4% vs. 1.8%), venous thromboembolism (0.55% vs. 0.29%), infection, and wound problems, were significantly higher in R‐TKA patients.Conclusions: This study provides detailed insights into t LOS, costs, and complications associated with specific etiologies of revision TKA. Our findings emphasize the need for targeted preoperative optimization and patient education. This approach can help reduce the incidence and burden of R‐TKA, improve patient care, optimize resource allocation, and potentially decrease the overall rates of complications in revision surgeries.Level of Evidence: Level III.

Background: Periprosthetic fractures following total hip arthroplasty are serious complications occurring in up to 2.4% of primary cases, contributing to significant morbidity, extended hospital stays, and elevated healthcare costs. Predicting these fractures remains a challenge despite advances in surgical techniques and prosthetic materials. Methods: This study analyzed 1,634,615 cases of primary THA from the NIS database (2016–2019) using propensity score matching to compare outcomes between patients with and without intraoperative periprosthetic fractures. Predictive models, including logistic regression, decision tree, and deep neural network, were evaluated for their ability to predict fracture risk. Results: Patients with periprosthetic fractures exhibited a 14-fold increase in pulmonary embolism risk, a 12-fold increase in infections, and a 5-fold increase in hip dislocations. Fractures extended hospital stays (3.8 vs. 2.5 days) and added approximately USD 32,000 in costs per patient. The predictive models yielded low accuracy (AUC max = 0.605), underscoring the complexity of predicting periprosthetic fractures. Conclusions: Intraoperative periprosthetic fractures in THA significantly elevate complication rates, costs, and length of stay. Despite extensive modeling efforts, accurate prediction remains difficult, highlighting the need to focus on preventive strategies, such as improved surgical techniques and real-time intraoperative monitoring.

Background: Anterior cervical discectomy and fusion (ACDF) is a common procedure for cervical radiculopathy and myelopathy. Severe obesity (BMI ≥40 or BMI ≥35 with comorbidities) is associ-ated with increased perioperative risks. This study examines the impact of severe obesity on out-comes in patients undergoing single-level ACDF. Methods :Data from the Nationwide Inpatient Sample (2016-2019) were analyzed, including 85,585 patients who underwent single-level ACDF. Patients were classified as severely obese (n = 4,935) or non-obese (n = 80,650). Outcomes such as length of stay, complications, and in-hospital mortali-ty were compared using SPSS and MATLAB, with a significance level of p < 0.05. Results: Severely obese patients were younger (54 vs. 55.7 years, p < 0.001) and had more comor-bidities like type 2 diabetes (38% vs. 17.8%, p < 0.001) and obstructive sleep apnea (31.1% vs. 9.5%, p < 0.001). They experienced longer hospital stays (1.92 vs. 1.65 days, p < 0.001) but similar in-hospital mortality (0.1%, p = 0.506). Severe obesity was linked to higher odds of complications, the risk of developing dehiscence was 8.2 times higher in severely obese patients. Respiratory failure had an odds ratio of 6.5, while myocardial infarction showed an odds ratio of 5.5. Horner syn-drome was 4.7 times more likely to occur, and pulmonary edema had an odds ratio of 4.5. Dural tear risk was also significantly elevated, with an odds ratio of 4.1.The risk of developing acute kid-ney injury were 2.6 times higher, while the risk of pulmonary embolism was 2.5 times higher. Dysphonia was also more common in severely obese patients, with an odds ratio of 2.2. Conclusion: Severe obesity is associated with higher complication rates and longer hospital stays following ACDF. Tailored perioperative management is essential to mitigate risks and improve outcomes in this high-risk population.

Background: Anterior cervical discectomy and fusion (ACDF) is a common procedure for cervical radiculopathy and myelopathy. Severe obesity (BMI ≥ 40 or BMI ≥ 35 with comorbidities) is associated with increased perioperative risks. This study examines the impact of severe obesity on outcomes in patients undergoing single-level ACDF. Methods: Data from the Nationwide Inpatient Sample (2016–2019) were analyzed, including 85,585 patients who underwent single-level ACDF. Patients were classified as severely obese (n = 4935) or non-obese (n = 80,650). Outcomes such as length of stay, complications, and in-hospital mortality were compared using SPSS and MATLAB, with a significance level of p < 0.05. Results: Severely obese patients were younger (54 vs. 55.7 years, p < 0.001) and had more comorbidities like type 2 diabetes (38% vs. 17.8%, p < 0.001) and obstructive sleep apnea (31.1% vs. 9.5%, p < 0.001). They experienced longer hospital stays (1.92 vs. 1.65 days, p < 0.001) but similar in-hospital mortality (0.1%, p = 0.506). Severe obesity was linked to higher odds of complications, including increased risks of dehiscence (OR 8.2), respiratory failure (OR 6.5), myocardial infarction (OR 5.5), Horner syndrome (OR 4.7), pulmonary edema (OR 4.5), and dural tears (OR 4.1). Risks of acute kidney injury, pulmonary embolism, and dysphonia were also elevated in severely obese patients. Conclusion: Severe obesity is associated with higher complication rates and longer hospital stays following ACDF. Tailored perioperative management is essential to mitigate these risks and improve outcomes in this high-risk population.