The Impact of Social Determinants of Health on Outcomes and Complications After Total Knee Arthroplasty: An Analysis of Neighborhood Deprivation Indices.

BACKGROUND: Social determinants of health (SDOH) are important factors in the delivery of orthopaedic care. The purpose of this study was to investigate the relationship between outcomes following total knee arthroplasty (TKA) and both the Social Vulnerability Index (SVI) and the Area Deprivation Index (ADI). METHODS: The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database was utilized to identify TKA cases for inclusion. Demographic characteristics and medical history were documented. The SVI, its subthemes, and the ADI were analyzed. Outcome data included length of stay, discharge disposition, postoperative change in the Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS, JR), 90-day incidences of emergency department (ED) visits, readmission, death, deep venous thrombosis (DVT) and/or pulmonary embolism (PE), periprosthetic fracture, implant failure, periprosthetic joint infection (PJI), and all-cause reoperation. Database cross-referencing was completed to document aseptic and septic revisions beyond 90 days postoperatively. Bivariate quartile-stratified and multivariable analyses were used to associate deprivation metrics with outcomes. RESULTS: A total of 19,321 TKA cases met inclusion criteria. Baseline patient characteristics varied among the SVI and/or ADI quartiles, with patients of non-White race and with a greater number of comorbidities noted in higher deprivation quartiles. Higher SVI and/or ADI quartiles were correlated with an increased rate of discharge to a skilled nursing facility (p < 0.05). A higher SVI and/or ADI quartile was associated with increased incidences of ED visits and readmissions postoperatively (p < 0.05). DVT and/or PE and long-term aseptic revision were the complications most strongly associated with higher deprivation metrics. Upon multivariable analysis, greater length of stay and greater incidences of ED visits, readmissions, DVT and/or PE, and aseptic revision remained significantly associated with greater deprivation based on multiple metrics. CONCLUSIONS: Greater deprivation based on multiple SVI subthemes, the composite SVI, and the ADI was significantly associated with increased length of stay, non-home discharge ED visits, and readmissions. The SVI and the ADI may be important considerations in the perioperative assessment of patients who undergo TKA. LEVEL OF EVIDENCE: Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Marital Status, Race, Insurance Type, and Socioeconomic Status-Assessment of Social Predictors for Outcomes After Total Knee Arthroplasty.

BACKGROUND: The purpose of this study was to investigate the effect of various social determinants of health on outcomes and dispositions after total knee arthroplasty (TKA). METHODS: A retrospective review was conducted on 14,462 consecutive TKA procedures between 2013 and 2021 at a multicenter hospital system. Data abstraction was done by inquiry to the Michigan Arthroplasty Registry Collaborative Quality Initiative. Data points requested included basic demographics, marital status, race, insurance status, socioeconomic status measured by the Area of Deprivation Index, perioperative course, and incidence of emergency department (ED) visits and readmissions within 3 months of surgery. Subsequent multivariate analyses were conducted. RESULTS: Unmarried patients required markedly greater lengths of hospital stay and had an increased rate of discharge to skilled nursing facilities and a higher likelihood of any purpose ED visit within 90 days of surgery compared with married patients, who had a significantly greater rate of same-day discharge ( P < 0.001). Race did not markedly correlate with outcomes. Medicare patients showed a greater rate of same-day discharge, nonhome discharge, and 90-day ED visits compared with privately insured patients ( P < 0.001). Medicaid patients were more likely than privately insured patients to have a 90-day ED visit ( P < 0.001). Socioeconomic status had a minimal clinical effect on all studied outcomes. CONCLUSION: Social factors are important considerations in understanding outcomes after TKA. Additional investigations are indicated in identifying at-risk patients and subsequent optimization of these patients.

Incidence of Pseudotumors in a Dual Modular Stem Construct With and Without Metal-on-Metal Bearing Surface.

BACKGROUND: The purpose of this study was to compare the incidence of pseudotumors in metal-on-metal (MoM) titanium modular neck hip arthroplasties to non-MoM modular neck hip arthroplasties. A secondary goal was to determine whether a correlation exists between elevated metal concentrations and pseudotumor incidence. METHODS: The data were collected and evaluated from 49 MoM joints and 26 non-MoM joints between the years 2012 and 2017. Hip ultrasonography was done after a minimum of 5 years postimplantation. Whole serum metal (titanium, cobalt, and chromium) concentrations were measured at the hip ultrasonography study. RESULTS: The average time elapsed between surgery and ultrasonography visit was 7.6 years. In the 49 patients with MoM joints, 22.4% (n = 11) had a pseudotumor. In the 26 patients with non-MoM joints, 9.1% of metal-on-polyethylene hips (n = 1) and 0% of ceramic-on-ceramic/polyethylene hips developed a pseudotumor. No significant statistical correlation was observed between serum metal concentrations and pseudotumor formation (P > 0.05). A significant correlation was observed of serum titanium concentration to pseudotumor size (P = 0.024). CONCLUSION: The incidence of pseudotumor formation in MoM total hip arthroplasties was more than five times the incidence associated with non-MoM bearings. The correlation between serum titanium concentration and pseudotumor size suggests that titanium levels may be a useful indicator for pseudotumor formation in patients with this particular titanium modular neck femoral implant. No notable correlation was observed between serum cobalt and chromium concentration and pseudotumor formation or size.

Comparison of Harris Hip Scores and Revision Rates in Metal-on-Metal Versus Non-Metal-on-Metal Total Hip Arthroplasty.

INTRODUCTION: This study compares functional outcome scores and revision rates between metal-on-metal (MoM) and non-MoM total hip arthroplasty patients. METHODS: A cohort of 75 patients who underwent implantation of the same dual modular hip arthroplasty between the years of 2004 and 2010 was enrolled. Patients were subsequently evaluated in 2015 to 2017 for joint revision history and functionality, as measured by the Harris hip score (HHS). Patients requiring a revision arthroplasty were not included in the HHS analysis. RESULTS: A total of 49 patients had MoM implants (65.3%), and 26 patients had non-MoM implants (34.8%). At a mean follow-up of 7.6 years, 10.2% (5/49) of MoM prostheses required revision, whereas 3.8% (1/26) of non-MoM prostheses required revision (P = 0.334). The mean HHS in the MoM cohort was 89.8, compared with 88.1 in the non-MoM cohort (P = 0.69). CONCLUSION: HHSs were not notably different between cohorts. The MoM cohort had three times as many revisions as the non-MoM cohort, but given the numbers available, this difference did not reach significance. Given the clinical importance of these revision data, further study is warranted to determine survivorship of the MoM versus non-MoM total hip arthroplasty at long-term follow-up.

Ultrasound findings in asymptomatic patients with modular metal on metal total hip arthroplasty.

OBJECTIVE: The use of metal-on-metal and modular total hip arthroplasty is associated with potentially serious local and systemic complications. The primary aim of this study was to identify the prevalence of a pseudotumor in asymptomatic patients with a particular metal-on-metal hip prosthesis after a minimum follow-up of 5 years using ultrasound evaluation. A secondary purpose was to identify associations between the presence of pseudotumor and serum metal ion levels following implantation. METHODS: We prospectively evaluated data collected from 36 asymptomatic patients who underwent implantation of a Profemur Z metal-on-metal total hip arthroplasty from January 2004 to January 2010. Serum metal ion levels were collected in 2012 and 2015. Hip ultrasounds were performed in 2015. RESULTS: Pseudotumors were found in 7/36 patients (19.4%). The average pseudotumor size measured 38.2 cm3 (range 7.35 cm3-130.81 cm3). Elevated metal ion levels were found in all patients at all time points. No statistical correlation was found between the presence of pseudotumor and patient age, age of the implant, component design, and any of the serum metal ion levels or ratios. CONCLUSIONS: One in every five asymptomatic patients with metal-on-metal implants was found to have a periarticular pseudotumor. There was no dose-dependent relationship found between elevated serum metal ion levels and the development of a pseudotumor. Our findings suggest that in patients with known elevated metal ion levels, continued monitoring of ion levels may not be a reliable predictor of pseudotumor formation, and ultrasound surveillance can and should be routinely used to document the presence and progression of pseudotumor.

Heterotopic Ossification Prophylaxis After Total Hip Arthroplasty: Randomized Trial of 400 vs 700 cGy.

BACKGROUND: Heterotopic ossification (HO) is a known complication following total hip arthroplasty. Radiation is an effective prophylaxis, but an optimal protocol has yet to be determined. We performed a randomized, double-blinded clinical trial in high-risk patients to determine the efficacy of 400 vs 700 cGy doses of radiation. METHODS: One hundred forty-seven patients undergoing total hip arthroplasty and at high risk for HO at an urban medical center were randomized to receive either a single 400 or 700 cGy dose of radiation postoperatively. High risk was defined as a diagnosis of diffuse idiopathic skeletal hyperostosis, hypertrophic osteoarthritis, ankylosing spondylitis, or history of previous HO. Radiation was administered on the first or second postoperative day. A single blinded reviewer graded radiographs taken immediately postoperatively and at a minimum of 6 months postoperatively using the Brooker classification. Progression was defined as an increase in Brooker classification. Operative data including surgical approach, implant fixation, revision surgery, and postoperative range of motion data were also collected. RESULTS: A significantly greater portion of patients who received the 400 cGy dose demonstrated progression of HO than patients who received the 700 cGy dose. There were no wound complications. No preoperative factors were associated with a higher rate of progression. Patients who progressed had less flexion on physical examination than patients who did not progress, but this was not clinically significant. CONCLUSION: Seven hundred centigray was superior to 400 cGy in preventing HO formation following total hip arthroplasty in high-risk patients and may be the more effective treatment in this population. Further studies comparing 700 cGy to dosages between 400 and 700 cGy may help to clarify if a more optimal dose can be identified.

Predictors and complications of blood transfusion in total hip and knee arthroplasty.

Perioperative patient optimization can minimize the need for blood transfusions in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). The purpose of this study was to determine predictors and complications of transfusions. This retrospective review analyzed 1795 patients who underwent primary THA and TKA at our institution between January 2011 and December 2012. Of the 1573 patients ultimately included the rates of transfusion were 9.27% in TKA and 26.6% in THA. Significant predictors for transfusion include: preoperative hemoglobin, age, female gender, body mass index, creatinine, TKA, operating room time, operative blood loss, and intra-operative fluids. The DVT rate was comparable, but deep surgical site infection rate among transfused patients was 2.4% compared to 0.5% in non-transfused patients (P = 0.0065).

Midterm results of a femoral stem with a modular neck design: clinical outcomes and metal ion analysis.

Modular neck femoral stems have a higher-than-anticipated rate of failure in registry results, but large single-center cohort studies are lacking. This is a retrospective cohort of 152 hips implanted with a single titanium stem with a modular titanium neck, presenting clinical, radiographic, and metal ion results at a mean 4.5-year follow-up. Five hips were revised during the study period, for an overall Kaplan-Meier survival of 0.894 at 8 years. There was one modular neck fracture (0.66%), but others demonstrated corrosion or adverse tissue reaction. Serum metal levels demonstrated wide variability. Despite good clinical results in the majority of patients, we confirmed an increased rate of femoral revision at mid-term follow-up, and therefore urge caution in the use of this particular stem design.

A prospective double-blind placebo controlled trial of topical tranexamic acid in total knee arthroplasty.

Tranexamic acid (TNA) reduces postoperative blood loss in general and obstetrical surgery but there is limited orthopaedic literature regarding its use in the topical setting. To study the effect of topical TNA after primary total knee arthroplasty (TKA), 101 patients were randomized to topical administration of 2.0g TNA in 75mL of normal saline (50 patients) or placebo (51 patients). Operative technique, drug administration, and venous thromboembolism prophylaxis were standardized. All patients underwent screening ultrasound of the operative extremity. Total blood loss was lower in the TNA group (940.2±327.1mL) than the placebo group (1293.1±532.7mL)(P<0.001), and four patients in the placebo group and none in the TNA group received postoperative transfusion (P=0.118). We recommend administration of topical TNA in primary TKA in healthy patients to decrease perioperative blood loss.

Trochanteric osteotomy and fixation during total hip arthroplasty.

Once used routinely, trochanteric osteotomy in total hip arthroplasty now is usually limited to difficult primary and revision cases. There are three types: the standard trochanteric osteotomy and its variations, the trochanteric slide, and the extended trochanteric osteotomy. Each has unique indications, fixation techniques, and complications. Primary total hip arthroplasty procedures requiring the enhanced exposure provided by trochanteric osteotomy may be needed in patients with hip ankylosis or fusion, protrusio acetabuli, proximal femoral deformities, developmental dysplasia, or abductor muscle laxity. Trochanteric osteotomies in revision arthroplasties, primarily the extended trochanteric osteotomy, facilitate the removal of well-fixed femoral components, provide direct access to the diaphysis for distal fixation, and enhance acetabular exposure.

Isolated revision of the patellar component in total knee arthroplasty.

BACKGROUND: Problems with the patellofemoral articulation are the most common causes of failure after total knee arthroplasty. However, there are few reports describing outcomes following isolated revision of the patellar component. METHODS: Forty knees with a Miller-Galante I prosthesis underwent isolated patellar revision (with or without lateral retinacular release). The Hospital for Special Surgery knee scores were collected prospectively, and radiographs made preoperatively and at the time of the final follow-up were analyzed with respect to alignment, component position, and patellar tracking. Particular attention was given to patients who had a reoperation or repeat revision and who had clinical or radiographic evidence of failure of the patellar revision. RESULTS: At a mean follow-up of sixty-two months, fifteen (38%) of the forty knees that had had an isolated revision of the patellar component failed a second time. Eight of them required a total of twelve additional operations at a mean of forty-nine months after the patellar revision. Three of the failures were severe enough to require revision of two or more of the components. Of the twenty-five knees that had not failed, the average Hospital for Special Surgery knee score at the time of the final follow-up was 87 points. Of the seven knees that did not undergo reoperation but were deemed to be failures on the basis of the patients' symptoms, the average Hospital for Special Surgery knee score at the time of the final follow-up was 72 points. CONCLUSIONS: Isolated patellar revision, with or without concurrent lateral retinacular release, was associated with a high rate of reoperation and a relatively low rate of success. Elements of the implant design and component alignment contributed to the patellar component failure; both should be scrutinized carefully in patients who are seen with this problem, prior to proceeding with isolated revision of the patellar component of a total knee arthroplasty. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See p. 2 for complete description of levels of evidence.