Relative frequency of primary total hip arthroplasty for avascular necrosis in the United States as compared to a regional center: A data review

Predictors of Reoperation and Survival Experience (Minimum One-Year) for Primary Versus Conversion Total Hip Arthroplasty in Young Patients

BACKGROUND

Total hip arthroplasty (THA), including primary and conversion procedures, is commonly used for many types of joint disease in patients under 65 years old, though few studies have evaluated THA outcomes in young patients (≤ 40 years old). This study examined a large cohort of patients who underwent THA at a young (≤ 40) age to identify predictors of reoperation and compare survivorship between primary and conversion THAs.

METHODS

A retrospective study was conducted on 497 patients who underwent 612 primary and conversion THAs at 40 years old or younger between 1990 and 2020. Medical records were reviewed to collect patient and surgical data. A multivariable logistic regression model identified independent predictors of reoperation, and Kaplan-Meier analysis with log-rank tests was used to compare survival curves by THA type.

RESULTS

The median age at surgery (interquartile range) was 31.4 years old (25.4 to 36.3). The median follow-up time was 6.6 years (range, 3.8 to 10.5). Conversion THAs had an increased rate of both revisions (12.3 versus 5.6%, P = 0.02) and non-revision reoperations (8.9 versus 3.2%, P = 0.03) compared to primary THAs. A ceramic-on-ceramic articulation (odds ratio [OR]: 5.17; P = 0.03) and a higher estimated blood loss (OR: 1.0007; P = 0.03) were independent predictors of reoperation for primary and conversion THA, respectively. Conversion THAs had a lower 15-year survival (77.8 versus 90.8%, P = 0.009) compared to primary THAs, with no difference in survival between patients ≤ 30 years old and patients 31 to 40 years old for both primary and conversion THAs.

CONCLUSIONS

Patients ≤ 40 years old who underwent primary and conversion THAs demonstrated an impressive 15-year survival comparable to that of older populations (74 to 93%), while conversion procedures had a higher reoperation rate. Though primary THA may be more ideal, there are promising outcomes for patients who need THA at a younger age than typically implemented, especially for those who are very young (≤ 30 years old).

Incidence and Clinical Risk Factors of Post-Operative Complications following Primary Total Hip Arthroplasty: A 10-Year Population-Based Cohort Study

Background: Total hip arthroplasty (THA) has become a growing treatment procedure for debilitating hip pathologies. Patients experienced post-operative complications and revision surgeries according to large THA registries. To fully understand the short-term and long-term post-operative outcomes following THA, the purpose of this study is to examine the incidence of post-operative complications following primary THA and to examine how this trend has changed over 10 years within community hospitals in the US using large databases. Methods: This study queried the State Inpatient Database (SID) for primary THA between 2006 and 2015. Individual patients were followed forward in time until the first instance of a post-operative complication. The multivariable logistic regression analyses were computed to examine which post-operative complications were independent predictors of pre-operative comorbidities. Results: Median age of patients was 67 years, and 56% of patients were female. Females with avascular necrosis (AVN) as an indication for THA had a 27% higher risk of complication. Females with osteoarthritis (OA) as an indication for THA had a 6% higher risk of complication. Post-operative complications occurred with higher frequencies in the first two months of THA and the highest risks of THA complications within the first 6 months. Conclusion: The most common indication is OA in elders with primary THA. Females and those of black ethnicity showed the greatest risks of THA complications. Data from our large study can be used to understand post-operative complications and readmissions after THA. Our study also provides data on risk factors associated with these complications.