McQuivey, Kade S.

Background: Debridement and implant retention (DAIR) has variable success as a treatment for acute periprosthetic joint infection (PJI), with generally poor outcomes reported in the literature 1 . Because of the unacceptably high failure rate of DAIR, we implemented a 2-stage debridement protocol that includes the use of high-dose antibiotic beads between stages for the treatment of acute PJI. In 2 previous studies, with an average follow-up of 3.5 years in each study, we reported overall infection-control rates of 87% and 90% 2,3 . Description: Following exposure of the joint, cultures are obtained, and all modular components are removed, scrubbed, and soaked in an antiseptic solution. A thorough irrigation and debridement with complete synovectomy is performed, followed by temporary reinsertion of the original modular parts. High-dose antibiotic cement beads are inserted into the joint, and the joint is closed. Approximately 5 to 6 days later, a second debridement is performed, the beads are removed, and the new modular, sterile components are implanted. The patient is placed on a course of intravenous and, later, oral antibiotics, in addition to a standard postoperative rehabilitation protocol. Alternatives: Long-term suppressive antibiotic therapy. One-stage DAIR. One-stage exchange arthroplasty. Two-stage exchange arthroplasty. Resection arthroplasty. Amputation. Rationale: The treatment of acute PJI has historically consisted of a single irrigation and debridement, with exchange of modular parts and retention of the components, followed by intravenous antibiotic therapy. Despite having lower rates of patient morbidity compared with a 2-stage exchange arthroplasty, this more traditional procedure also has a higher rate of failure, with reported rates as high as 60% to 84% 4–12 . The utility of component retention continues to be a topic of debate 13 . Alternatives to component retention include both 1- and 2-stage exchange procedures. Although these modalities offer potentially higher rates of infection control, they are associated with substantial patient morbidity, particularly in patients with well-fixed implants 14–16 . Furthermore, exchange procedures may result in substantial iatrogenic bone loss, which can be problematic in revision total joint arthroplasty procedures, in which bone stock may already be limited. The double-DAIR protocol offers infection-control rates that are comparable with those of component-exchange procedures, but with the lower patient morbidity associated with component-retention procedures. Furthermore, the double-DAIR procedure provides the added benefit of retaining important bone stock. Expected Outcomes: The success rate for the double-DAIR procedure has been reproducible, with infection-control rates of 87% and 90% reported in 2 studies from a single cohort at our institution 2,3 . These rates represent a substantial improvement compared with a single irrigation and debridement 1 , and are on par with those reported for 2-stage exchange arthroplasty procedures 17–21 . The infection-control rates of the double-DAIR procedure did not significantly vary depending on whether infection occurred following a total knee or total hip arthroplasty. However, not surprisingly, patients who underwent debridement following a revision procedure had a lower rate of success (77.1% successful infection control) compared with patients debrided following a primary procedure (93.8% successful infection control). We could not demonstrate an association with organism and success or failure of treatment. Although not significant, there was a trend toward an association between the time from symptom onset to initial treatment and infection control (p = 0.07) 2 . Patients with successful infection control underwent the initial debridement an average of 6.2 days after symptom onset, compared with 10.7 days in patients in whom treatment had failed. Several other studies have demonstrated that successful infection control is associated with earlier initial irrigation and debridement 22–27 . We strongly support that, in the setting of confirmed acute PJI, prompt initiation of treatment optimizes the chances for successful infection control. Important Tips: Thorough debridement is key to successful infection control of infection. Antibiotic-loaded bone cement has repeatedly been demonstrated to be safe, and we recommend its use 28–31 . Extended oral antibiotics following debridement with component retention can increase infection-free survivorship 32 .

Purpose To determine the 50 most frequently cited studies in the orthopaedic shoulder arthroscopy literature and to conduct a bibliometric analysis of these studies. Methods The Clarivate Analytics Web of Knowledge database was used to gather data and metrics using Boolean queries to capture all possible iterations of shoulder arthroscopy research. The search list was sorted so that articles were organized in descending order based on the number of citations and included or excluded based on relevance to shoulder arthroscopy. The information extracted for each article included author name, publication year, country of origin, journal name, article type, and the level of evidence. Results For these 50 studies, the total number of citations was calculated to be 13,910, with an average of 278.2 citations per paper. The most‐cited article was cited 1134 times, whereas the second‐ and third‐most cited articles were cited 920 and 745 times, respectively. All 50 articles were published in English and came from 7 different orthopaedic journals. The United States was responsible for most of the included articles (31), followed by France (9) and Japan (3). Conclusions The majority of the most‐cited articles in shoulder arthroscopy are case series and descriptive studies originating from the United States. In addition, more than one half of the top 50 most‐cited studies were published after 2004, which suggests that article age may be less important in the accumulation of citations for a rapidly growing field like shoulder arthroscopy. Clinical Relevance The top 50 most‐cited studies list will provide researchers, medical students, residents, and fellows with a foundational list of the most important and influential academic contributions to shoulder arthroscopy.

Background: Hip arthroscopy has been previously demonstrated to be an effective treatment for adult mild hip dysplasia. There are many radiographic parameters used to classify hip dysplasia, but to date few studies have demonstrated which parameters are of most importance for predicting surgical outcomes. Purpose: To identify preoperative radiographic parameters that are associated with poor outcomes in the arthroscopic treatment of adult mild hip dysplasia. Study Design: Case-control study; Level of evidence, 3. Methods: Radiographic analysis was performed in patients with mild hip dysplasia who underwent arthroscopic surgery between 2009 and 2015. Preoperative radiographic measurements included lateral center edge angle, Tönnis angle, neck shaft angle, anterior center edge angle, alpha angle, femoral head extrusion index, and acetabular depth-to-width ratio. Failure was defined as failure to achieve the minimal clinically important difference (MCID) utilizing the modified Harris Hip Score or as the need for secondary operation. The equal variance t test was used to analyze radiographic parameters. Statistical significance was determined using a P value of .05. Results: A total of 373 hips underwent analysis with an average follow-up of 41 months (range, 24-102 months). Of these, 46 hips (12%) required secondary operation, and 95 (25%) failed to meet the MCID. The overall failure rate was 32.4%. There was no single measurement or combination thereof associated with failure to reach the MCID. Higher preoperative Tönnis angles were associated with secondary operation, with a mean of 6.7° (95% CI, 5.3°-8.1°) in the secondary operation group versus 4.8° (95% CI, 4.4°-5.3°) in the nonsecondary operation group ( P = .006). The odds ratio was 1.12 (95% CI, 1.0-1.2; P = .05) per degree increase in Tönnis angle for secondary operation. In patients with a Tönnis angle >10°, 84% required secondary operation. Conclusion: Higher Tönnis angles portend a higher risk for revision surgery. The probability of secondary operation was increased by a magnitude of 1.12 with each degree increase in the Tönnis angle. In patients with a Tönnis angle >10°, 84% required a secondary operation.

We present a case of an 82-year-old female with a history of right total knee arthroplasty 11 years prior. She was admitted after a ground-level fall and developed progressive pain and swelling of her right knee. She had no history of complications with her total knee replacement. Radiographs of the knee and hip were negative for acute fracture, dislocation, or hardware malalignment. Knee aspiration was performed and revealed inflammatory exudate, synovial fluid consistent with crystal arthropathy, and no bacterial growth. She was diagnosed with an acute gout flare, and her symptoms significantly improved with steroids and anti-inflammatory treatment. Orthopedic surgeons should be aware of the potential for crystal arthropathy in the setting of total joint arthroplasty and evaluate for crystals before treating a presumed periprosthetic joint infection.