Bilateral Total Hip Arthroplasty: Outcomes of Staged Versus Simultaneous Procedures Performed Using an Anterior-Based Muscle-Sparing Approach.

BACKGROUND: The incidence of total hip arthroplasty (THA) in the United States continues to increase due to its ability to markedly improve patients' quality of life. This study investigated and compared the perioperative and postoperative outcomes of simultaneous (SI-THA) and staged (ST-THA) bilateral THA procedures using an anterior-based muscle-sparing (ABMS) approach. METHODS: This retrospective case control study evaluated perioperative and postoperative outcomes from primary bilateral SI-THA or ST-THA (within 365 days) performed with the ABMS approach by 3 surgeons at a single institution between January 2013 and August 2020. A total of 226 patients (113 in each cohort) were matched based on age, sex, body mass index, and comorbidity score. RESULTS: Compared to the ST-THA group, the SI-THA had shorter anesthesia duration (P < .001) and shorter length of stay (P < .001), but longer length of surgery (P = .002). There was no statistical significance between groups in blood transfusion rates, discharge dispositions, emergency department visits, hospital readmissions, or postoperative complications within one year. CONCLUSIONS: The results of this study demonstrate that SI-THA and ST-THA yield comparable results using the ABMS approach. Our perioperative and postoperative results suggest low rates of complications, emergency department visits, readmissions, and high rates of patient satisfaction scores. Therefore, both SI-THA and ST-THA can be considered by experienced surgeons as treatment for advanced bilateral hip arthritis.

Elevated Intra-Articular Cobalt and Chromium Levels in Mechanically Assisted Crevice Corrosion in Metal-on-Polyethylene Total Hip Arthroplasty.

BACKGROUND: Failed total hip arthroplasty (THA) caused by mechanically assisted crevice corrosion (MACC) has serious consequences such as adverse local tissue reaction (ALTR). Serum cobalt (Co) and chromium (Cr) ion levels have been used to diagnose taper corrosion, but have not been shown to be an accurate measure of the severity of MACC or associated ALTRs. Additionally, elevated serum ions are not specific in patients with multiple artificial joints. METHODS: We examined the relationship between serum and intra-articular (IA) Co and Cr levels in a cohort of 20 patients undergoing revision THA, 16 who had symptomatic MACC. IA Co and Cr levels in MACC patients were compared with demographic, pre-operative, and operative findings. RESULTS: Serum and IA metal levels were found to be relatively low in THA patients undergoing revision surgery for isolated instability, aseptic loosening, or infection (average serum Co 0.03 ppb [parts per billion], IA Co 1.4 ppb, serum Cr 0.32 ppb, IA Cr 3.3 ppb). In patients with MACC, average IA Co (940 ppb) was significantly higher than serum Co (5.1 ppb) (P = .0003) and IA Cr (491 ppb) was significantly higher than serum Cr (1.3 ppb) (P = .0003). IA Co level was associated with shorter time of hip symptoms to revision surgery (P = .0043). CONCLUSION: Serum levels of Co and Cr correlated with joint levels in the entire cohort, but IA levels of MACC patients were 100 times greater than serum levels. IA Co and Cr levels may be useful in confirming MACC in a specific joint and the striking elevation may explain symptoms and ALTR with relatively low serum values.

The anterior-based muscle-sparing approach is cost-effective when compared with posterolateral and direct anterior approaches for total hip arthroplasty.

PURPOSE: Research relating to Total Hip Arthroplasty (THA) has found the anterior-based muscle-sparing (ABMS) approach improves both intraoperative and postoperative outcomes when compared to other THA approaches. This study compares the costs and outcomes of the ABMS approach and standard of care (SOC) to determine the relative cost-effectiveness. METHODS: A decision-analytic model was utilized to estimate intraoperative outcomes (i.e. length of procedure, length of stay (LOS), and transfusion rates) and 90-day postoperative complications (deep infection, periprosthetic fracture, and dislocation). Data relating to postoperative complications, intraoperative outcomes, and costs (adjusted to 2023 USD) were obtained from the literature. Model results were presented as incremental costs and complications avoided using a willingness-to-pay threshold of $100,000. We conducted both one-way sensitivity analysis (OWSA), varying each parameter individually within a specific range, and probabilistic sensitivity analysis (PSA) where parameters were varied simultaneously. In scenario analysis, ABMS was also compared to the posterior approach (PA) and direct anterior approach (DAA) individually. RESULTS: ABMS THA was found to have superior results compared to SOC THA over a 90-day time horizon since it decreased major complications by 0.00186 per patient and cost by $3,851 per patient. The PSA found the ABMS approach dominates SOC and is cost-effective in approximately 98.29% and 100% of 10,000 iterations, respectively. Comparing ABMS with only PA procedures increased cost savings per patient to $4,766 while it decreased to $3,242 when comparing ABMS to only DAA procedures. Length of procedure, LOS, and discharge disposition were the main cost drivers. CONCLUSIONS: This analysis demonstrates the ABMS approach for THA is a cost-effective technique when compared to PA and DAA, which may provide an opportunity for cost savings to the healthcare system.

Early Debris Formation with a Porous Tantalum Glenoid Component: Radiographic Analysis with 2-Year Minimum Follow-up.

BACKGROUND: Porous tantalum has been used effectively in hip, knee, and reverse shoulder arthroplasty implants. However, a first-generation porous tantalum glenoid component for use in anatomic shoulder arthroplasty previously demonstrated failure, with failure usually preceded by the appearance of intra-articular metallic debris. After redesign, the component was reintroduced in 2009. The purpose of the current study was to evaluate the radiographic and clinical outcomes of the redesigned glenoid component. METHODS: Sixty-eight patients undergoing total shoulder arthroplasty received a Trabecular Metal porous tantalum glenoid component (73 components; 5 patients underwent staged bilateral procedures). No polymethylmethacrylate cement was used (off-label usage in the U.S.). A grading system to assess metallic debris formation was developed using radiographs of the previous generation of porous tantalum glenoid components that failed. Radiographs from the current series were independently reviewed by 2 shoulder arthroplasty specialists, and their results were compared. Glenoid components were evaluated for signs of bone ingrowth and metallic debris formation. RESULTS: Sixty-six (90%) of the 73 components were evaluated at a minimum of 2 years of follow-up (mean radiographic follow-up of 50.8 months; range, 24 to 68 months). Of these, 92.4% demonstrated minimal or no glenoid radiolucency. Overall, the prevalence of metallic tantalum debris formation was 44% (29 of 66). Sequential radiograph review demonstrated that the incidence of metallic debris formation increased for each year of follow-up, with radiographs from 2, 3, 4, and ≥5 years of follow-up demonstrating a metallic debris incidence of 23%, 36%, 49%, and 52%, respectively. Additionally, the severity of metallic debris formation increased with follow-up duration. There was no component dissociation or revision due to implant breakage in this series. CONCLUSIONS: The porous tantalum glenoid component studied had excellent short-term component fixation. However, the development of metallic debris, increasing in both overall incidence and degree of severity over time, raises concern for potential failure of this glenoid component. Longer follow-up is required. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Cost and Outcome Effectiveness of Total Hip Replacement: Technique Choice and Volume-Output Effects Matter.

BACKGROUND: Total hip replacement (THR) must be managed in a more sustainable manner. More cost-effective surgical techniques and the centralization/regionalization of services are two solutions. The former requires an assessment of newer minimally invasive and muscle-sparing surgical techniques. The latter necessitates an effective volume-outcome (VO) relationship. Prior studies have failed to evaluate and control for the VO relation. OBJECTIVE: The objective of this study was to evaluate the relative cost and outcome effectiveness of two minimally invasive and one muscle-sparing techniques while evaluating and controlling for a potentially endogenous VO relation. METHODS: An all payer claims database for all THR performed in Maine in 2011 was used. The cost and outcome effectiveness of newer minimally invasive (modified Hardinge) and muscle-sparing (modified Watson-Jones) techniques were compared with the standard bearer posterior minimally invasive method. Using regression analysis, the outcomes analyzed were as follows: total costs, length of hospital stay, nursing care and home discharges, and use of physical therapy. Regression analysis was also used to evaluate and control for VO effects. RESULTS: (1) Newer muscle-sparing and minimally invasive approaches are substantially more effective; (2) irrespective of technique, higher volume surgeons are more effective; (3) technique-specific VO effects for more complex techniques exist and show substantial savings when yearly volume exceeds 30-50; and (4) the anterolateral muscle-sparing technique is accessible to the average surgeon. CONCLUSION: Reliance on newer surgical techniques and centralization/regionalization of THR services can reduce costs.