All right, good afternoon. My name is Charles Wang. Today I'll be presenting the findings of our study entitled Severity of Conjugal Labral Junction Degeneration Predicts Conversion of Total Hip Arthroplasty after Arthroscopic Femoralis Tidal Impingement Treatment at Minimum 10 Years Follow-Up. I want to thank all my co-authors and mentors for their help in completing this study. So I and my co-authors and I have no relevant disclosures. So much of what we know about the natural history and development of hip osteoarthritis comes from observational and cadaveric studies. In 1979, Dr. William Harris was the first to observe that labral tears occurred at the same location of conjural wear. And in 2001, McCarthy et al. performed a retrospective review of 436 hip arthroscopies as well as examination of 54 cadaveric acetabulums. They noticed 73% of these patients or specimens who had fraying or a tear of the labrum also had conjural damage. They conclude that the labral disruption and degenerative joint disease are frequently part of a continuum of joint disease. And in 2003, Reinhold Gans introduced a new player to the field, femoralis tabular impingement, as the mechanism of early onset osteoarthritis in nondisplastic hips. The conjural labral junction is the area between the labrum and the cartilage where concomitant wear was often seen and exhibits several unique properties. Histological assessment of this area revealed a unique crimped collagen arrangement, which imparts an extension recovery property of the labrum, provides a degree of elasticity even in the absence of elastin. Rejapa et al. concluded that this property of crimping allows high-stress areas of the body, such as the labrum, to extend, flex, and twist with loading without permanent deformation while still contributing to its stability. We also know through Philippon's group that this junction is tough to heal. In 2007, they reported that even after surgical repair of a labral tear with a delaminated conjural labral junction, the conjural labral junction remained only partially healed. And the healing that did occur was the result of scar extension from the vascularized capsular aspect of the labrum and not from the junction itself. In 2005, Beck described the classification system to better characterize patterns and progression of acetabular cartilage wear. Grade 0 includes a macroscopically sound cartilage with no evidence of wear. Grade 1 includes just superficial roughening of the articular cartilage at the transition zone. Grade 2 includes the dreaded carpet or wave phenomenon where the articular cartilage at the transition zone loses its fixation to the subchondral bone. Grade 3 and 4 include progressive flat formation of the separated fragment. Subsequent studies have demonstrated good inter- and intra-observer agreement of this classification system, approximately 0.84 to 0.94. No studies to date have correlated stages of conjural labral junction wear and failure of FAI and labral tear treatment. So therefore, the purpose of this study was to identify the location and severity of intra-op pathology at time of arthrosurgery for FAI as risk factors for conversion to total hip arthroplasty utilizing long-term follow-up. This was a retrospective study of prospectively collected data. Adult patients greater than or equal to the age of 18 undergoing hip arthroscopy for FAI with a minimum 10-year follow-up were included, while patients with radiographic evidence of hip dysplasia and a history of previous hip surgery were excluded. This yielded 109 patients. The primary endpoint was whether or not the patients converted to a total hip replacement. Intra-op measurements included the outer bridge grade, location of most severe conjural wear, presence of a conjural flap, degree of the conjural labral degeneration, and type of labral management, whether it was labral debridement or repair. Baseline demographic findings revealed that older age, a lower tonus angle, and types of FAI were significantly associated with conversion to total hip arthroplasty. When looking at intra-op findings, an outer bridge grade 4, a BET grade 4, and a posterior superior acetabular wear were significantly associated with conversion to total hip arthroplasty. To see which variables were independent risk factors for conversion to total hip arthroplasty, a multivariate logistic regression model was used with both baseline and intra-op variables. This identified older age, grade 4 conjural labral wear, and combined FAI were identified significant risk factors for conversion to total hip arthroplasty. So in conclusion, the grade 4 degeneration of the conjural labral junction was an independent risk factor for conversion to total hip arthroplasty. This study offers better insight into the importance of the conjural labral junction in terms of the evolutionary role of a hip osteoarthritis. There are limitations involved with this study. It was a single surgeon assessment of the status of the conjural labral junction. Some variables treaded towards but did not meet statistical significance. And since this presentation had been submitted, we submitted our manuscript to AJSM which did actually reveal type of labral management, specifically debridement was also statistically significant towards conversion to total hip arthroplasty. There were no second looks to actually confirm whether or not the conjural labral junction had actually healed after labral repair. But this study does beg the question, is it prudent to manage FAI prior to the delamination or the point of no return? And it also gives more emphasis on the need to specifically focus on how we can get this delaminated conjural labral junction to heal. Thank you.

Charles Wang

study

Conjugal Labral Junction Degeneration

Total Hip Arthroplasty

Arthroscopic Femoralis Tidal Impingement Treatment