Reporting of complications after total hip arthroplasty (THA) is not standardized, and it is done inconsistently across various studies on the topic. Advantages of standardizing complications include improved patient safety and outcomes and better reporting in comparative studies. The purpose of this project was to develop a standardized list of complications and adverse events associated with THA, develop standardized definitions for each complication, and stratify the complications. A further purpose was to validate these standardized THA complications. The Hip Society THA Complications Workgroup proposed a list of THA complications, definitions for each complication, and a stratification scheme for the complications. The stratification system was developed from a previously validated grading system for complications of hip preservation surgery. The proposed complications, definitions, and stratification were validated with an expert opinion survey of members of The Hip Society, a case study evaluation, and analysis of a large administrative hospital system database with a focus on readmissions. One hundred five clinical members (100%) of The Hip Society responded to the THA complications survey. Initially, 21 THA complications were proposed. The validation process reduced the 21 proposed complications to 19 THA complications with definitions and stratification that were endorsed by The Hip Society (bleeding, wound complication, thromboembolic disease, neural deficit, vascular injury, dislocation/instability, periprosthetic fracture, abductor muscle disruption, deep periprosthetic joint infection, heterotopic ossification, bearing surface wear, osteolysis, implant loosening, cup-liner dissociation, implant fracture, reoperation, revision, readmission, death). Acceptance and use of these standardized, stratified, and validated THA complications and adverse events could advance reporting of outcomes of THA and improve assessment of THA by clinical investigators. Level V, therapeutic study.

Background: Changes in the intra-articular inflammatory state during the immediate period after an acute anterior cruciate ligament (ACL) rupture are not well defined. Purpose: To evaluate changes in the concentration of select proinflammatory and anti-inflammatory synovial fluid cytokines during the interval between an ACL injury and surgical reconstruction. Study Design: Descriptive laboratory study. Methods: In patients with an acute ACL injury, a synovial fluid sample was obtained from the injured knee during the initial office visit within 2 weeks of the inciting traumatic event. An additional synovial fluid sample was collected at the time of ACL reconstruction just before the surgical incision. Synovial fluid samples from both the acute injury and the surgery time points were processed with a protease inhibitor, and the concentrations of 10 cytokines of interest were measured using a multiplex magnetic bead immunoassay. The primary outcome was the change in cytokine concentrations between time points. Results: A total of 20 patients with a mean age of 30.2 ± 8.3 years were included. The acute injury synovial fluid samples were collected at 6.6 ± 3.8 days after the injury. The surgical synovial fluid samples were collected at 31.6 ± 15.6 days after the acute injury samples. Based on a series of linear mixed-effects models to control for the effect of concomitant meniscal injuries and by-patient variability, there was a statistically significant increase in the concentrations of RANTES and bFGF and a statistically significant decrease in the concentrations of IL-6, MCP-1, MIP-1β, TIMP-1, IL-1Ra, and VEGF between time points. Conclusion: This study demonstrates the ongoing alterations in the intra-articular microenvironment during the initial inflammatory response in the acute postinjury period. We identified 6 synovial fluid cytokines that significantly decreased and 2 that significantly increased between the first clinical presentation shortly after the injury and the time of surgery 1 month later. Clinical Relevance: This study describes the molecular profile of the inflammatory changes between the time of an acute ACL injury and the time of surgical reconstruction 1 month later. A greater understanding of the acute inflammatory response within the knee may be helpful in identifying the optimal timing for a surgical intervention that balances the risk of chondral damage with the likelihood of successful, well-healed reconstruction.