Number Of Total Hip Arthroplasties Research Articles

What are the predisposing factors for periprosthetic fractures following total hip arthroplasty? - a National Inpatient Sample-based study.

With a progressive rise in the number of total hip arthroplasties (THA) over the past decades, the proportion of patients sustaining peri-prosthetic fractures (PPF) has been substantially increasing. In this context, the need for clearly understanding the factors predisposing patients to PPF following THA and the impact of these adverse complications on the overall healthcare burden cannot be understated. Based upon the Nationwide Inpatient Sample (NIS) database, the patients who underwent THA in the United States between 2016 and2019 (with ICD-10 CMP code) were identified. The patients were divided into 2 groups; group A - patients who sustained PPF and group B - those who did not. The information about the patients' demographic profile, medical comorbidities; and hospital admission (including length of stay and expenditure incurred) were analysed; and compared between the 2 groups. Overall, 367,890 patients underwent THA, among whom 4,425 (1.2%) sustained PPF (group A). The remaining patients were classified under group B (363,465 patients). On the basis of multi-variate analysis (MVA), there was a significantly greater proportion of females, elderly patients, and emergent admissions (p < 0.001) in group A. The length of hospital stay, expenditure incurred and mortality were also significantly higher (p = 0.001) in group A. Based on MVA, Down's syndrome (odd's ratio 3.15, p = 0.01), H/O colostomy (odd's ratio 2.09, p = 0.008), liver cirrhosis (odd's ratio 2.01, p < 0.001), Parkinson's disease (odd's ratio 1.49, p = 0.004), morbid obesity (odd's ratio 1.44, p < 0.001), super obesity (odd's ratio 1.49, p = 0.03), and H/O CABG (coronary artery bypass graft; odd's ratio 1.21, p = 0.03) demonstrated significant association with PPF (group A). Patients with PPF require higher rates of emergent admission, longer hospital stay and greater admission-related expenditure. Female sex, advanced age, morbid or super obesity, and presence of medical comorbidities (such as Down's syndrome, cirrhosis, Parkinson's disease, previous colostomy, and previous CABG) significantly enhance the risk of PPF after THA. These medical conditions must be kept in clinicians' minds and close follow-up needs to be implemented in such situations so as to mitigate these complications.

Impact of COVID-19 on total hip arthroplasty: results from California state inpatient database

Background: COVID-19 pandemic has significantly affected orthopedic surgery, resulting in postponements and cancellations. The aim of this study is to determine the possible effects of COVID-19 on the number of total hip arthroplasty (THA) hospitalizations and hospital outcomes using a large database. Methods: We conducted a retrospective analysis of data gathered and stored in the California State Inpatient Database (SID) during 2019 and 2020. All THA hospitalizations ≥18 yr that occurred in 2019 and 2020 and COVID-19 hospitalizations that occurred in 2020 were used for the analysis. The primary outcomes of the study were trends in THA hospitalizations between 2019 and 2020. Secondary outcomes were mortality, surgical, medical, and other complications, and prolonged length of stay. Results: A total of 36,760 and 20,243 THA hospitalizations occurred during 2019 and 2020, respectively. Trends in THA hospitalizations during 2019 and 2020 showed that the rates of these hospitalizations were substantially lower throughout 2020. Logistic regression analysis showed that the odds of mortality (odds ratio [OR], 2.77; 95% CI, 1.38-5.53), surgical complications (OR,1.61; 95% CI, 1.36-1.89), medical complications (OR,1.27; 95% CI, 1.20-1.33), other complications (OR,1.42; 95% CI, 1.19-1.69), and prolonged length of stay (OR,1.10; 95% CI, 1.05-1.16) were significantly higher during 2020. Conclusions: Our findings show that during COVID-19 pandemic THA hospitalizations were prioritized based on case severity. By the end of 2020 THA hospitalizations did not steeply decrease in numbers compared to the advent of the pandemic, indicating that orthopedic surgeons and other healthcare professionals functioned optimally even during the COVID-19 pandemic.

Gluteus maximus transfer for wound closure and treatment of abductor deficiency: a single-plastic surgeon series.

Due to the increasing number of total hip arthroplasties (THA), the number and complexity of revision procedures are also on the rise. For complex cases such as periprosthetic joint infections with soft tissue compromise or for abductor muscle deficiencies, one of the treatment options is a gluteus maximus flap (GMF) that covers dead space and can help restore the failed abductor mechanism. The purpose of this study is to investigate the outcomes of a single-plastic surgeon's series of GMF procedures. This retrospective review reports on 57 patients (mean follow-up 39.2months) undergoing GMF transfers for abductor insufficiency on native hip (N = 16), for abductor insufficiency in aseptic revision THA (rTHA) (N = 16), for soft tissue defects in aseptic rTHA (N = 8) and for soft tissue defects in septic rTHA (N = 17) by a single plastic surgeon over a 10-year period. Revision-free survival and complication rates were assessed and risk factors were analyzed with Cox-regression analysis. The reoperation-free survival rate of GMF for abductor insufficiency in native hips was 100%. GMF procedures for soft tissue defects in septic rTHA had the lowest cumulative revision-free survival (34.3%) and highest reinfection rates (53.9%). More than three prior surgeries (HR = 2.9, p = 0.020), presence of infection (HR = 3.2, p = 0.010) and resistant organisms (HR = 3.1, p = 0.022) significantly increased the risk of revision. GMF is a viable option for addressing abductor insufficiency in native hip joints. However, high revision and complication rates are reported for GMF in septic rTHA. This study highlights the need to clarify the circumstances for which the flap reconstruction will be indicated.

Mid-term clinical and radiographic outcomes after primary total hip replacement with fully hydroxyapatite-coated stem: A cross-sectional study

Background The number of total hip arthroplasties increases every year as the population ages. The purpose of the study was to evaluate mid-term clinical and radiological results for a minimum of two years and the survival rate at the 5-year follow-up period using a fully hydroxyapatite (HA)-coated stem. Methods A single-center retrospective observational study was conducted, in which 121 primary total hip arthroplasties (THA) were performed between 2013 and 2015 using a standard offset Corail fully HA-coated stem. The study included 108 patients, with a median age among all patients of 55.00 years (range 18.0–79.0 years). The median follow-up time was 4 years and 9 months. Results Stem survival for any reason was 98.4% at 5 years. The mean Harris Hip Score and Engh Grading Scale before surgery and at the follow-up visit show statistically significant improvement, accordingly (44.70 vs 98.13; p &lt; 0.001) and (17.42 vs 19.68; p &lt; 0.01). There is no statistically significant correlation between radiological and clinical results and no correlation between follow-up time and results. Conclusions A completely coated hydroxyapatite standard offset Corail stem shows an excellent survival rate for a 5-year follow-up. Although the radiological results are not perfect, the clinical evaluation shows that the patients are satisfied and are not limited in their daily activities as before the surgery.

Outcomes of morbidly obese patients undergoing total hip arthroplasty with the anterior-based muscle-sparing approach.

Obesity is associated with an increased risk of hip osteoarthritis, resulting in an increased number of total hip arthroplasties (THAs) performed annually. This study examines the peri- and postoperative outcomes of morbidly obese (MO) patients (BMI ≥ 40 kg/m2) compared to healthy weight (HW) patients (BMI 18.5 to < 25 kg/m2) who underwent a THA using the anterior-based muscle-sparing (ABMS) approach. This retrospective cohort study observes peri- and postoperative outcomes of MO and HW patients who underwent a primary, unilateral THA with the ABMS approach. Data from surgeries performed by three surgeons at a single institution was collected from January 2013 to August 2020 and analyzed using Microsoft Excel and Stata 17.0. This study compares 341 MO to 1,140 HW patients. Anaesthesia, surgery duration, and length of hospital stay was significantly lower in HW patients compared to MO. There was no difference in incidence of pulmonary embolism, periprosthetic fracture, or dislocation between the two groups. The rate of infection in MO patients (1.47%) was significantly higher than HW patients (0.14%). Preoperative patient-reported outcome measures (PROMs) show a significantly higher pain level in MO patients and a significantly lower score in functional abilities. Overall, six-week and one-year postoperative data show higher levels of pain, lower levels of functional improvement, and lower satisfaction scores in the MO group. The comorbidities of obesity are well studied; however, the implications of THA using the ABMS approach have not been studied. Our peri- and postoperative results demonstrate significant improvements in PROMs in MO patients undergoing THA. However, the incidence of deep infection was significantly higher in this group compared with HW patients.

Projections and Epidemiology of Primary Hip and Knee Arthroplasty in Medicare Patients to 2040-2060.

The present study used data from the Centers for Medicare & Medicaid Services (CMS) Medicare/Medicaid Part B National Summary and combined procedure counts with use of Current Procedural Terminology (CPT) codes to identify whether the procedure was a primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) procedure. In 2019, the annual volume of primary TKA was 480,958 and that of primary THA was 262,369. These values formed a baseline from which we generated point forecasts for 2020-2060 and 95% forecast intervals (FIs). Between 2000 and 2019, the estimated annual volume of THA increased by 177% and that of TKA increased by 156% on average. Regression analysis projected an annual growth rate of 5.2% for THA and 4.44% for TKA. Based on these yearly projected increases, an estimated increase of 28.84% and 24.28% is expected for each 5-year period after 2020 for THA and TKA, respectively. By 2040, the number of THAs is projected to be 719,364 (95% FI, 624,766 to 828,286) and the number of TKA is projected to be 1,222,988 (95% FI, 988,714 to 1,512,772). By 2060, the number of THAs is projected to be 1,982,099 (95% FI, 1,624,215 to 2,418,839) and the number of TKAs is projected to be 2,917,959 (95% FI, 2,160,951 to 3,940,156). In 2019, Medicare data showed that THA constituted approximately 35% of TJA procedures performed. Based on 2019 total volume counts, our model forecasts an increase in THA procedures of 176% by 2040 and 659% by 2060. The estimated increase for TKA is projected to be 139% by 2040 and 469% by 2060. An accurate projection of future primary TJA procedure demands is important in order to understand future health-care utilization and surgeon demand. This finding is only applicable to a Medicare population and demands further analysis to see if this extends to other population groups. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Evaluation of the Validity and Reliability of a Persian Version of the Forgotten Joint Score in Patients Undergoing Total Hip Arthroplasty.

The increasing number of total hip arthroplasties (THA) has led to increased patient demands and expectations, making it crucial to assess patients' ability to "forget" their implants in daily life. This study aimed to determine the reliability and validity of a Persian version of the Forgotten Joint Score (P-FJS) in THA patients. The questionnaire was translated bidirectionally with the permission of the questionnaire designer. Data were collected from 2018 to 2020 and included 142 patients who had undergone THA by the same surgeon at least one year ago. Participants completed the FJS questionnaire twice within a one-week interval, and the validity, reliability, and feasibility of the questionnaires were assessed using statistical tests on the HHS and OHS forms completed by all participants. In 142 patients (52.1% male) with a mean age of 65 ± 0.5 years who answered the questionnaires, P-FJS correlated strongly with OHS and HHS. The internal consistency (α = 0.91) and reproducibility of the questionnaire were excellent. None of the floor and ceiling effects were detected. The P-FJS questionnaire in the THA is considered a legitimate, repeatable, and self-administered survey that can be compared to its English-language counterpart. In addition, it is noteworthy that this version does not show any floor or ceiling effects.

Patient-related factors influencing the outcome of primary total hip arthroplasty: Age, gender, socioeconomic status, body mass index, and preoperative health status

ABSTRACT The number of total hip arthroplasty (THA) operations is expected to increase dramatically during the coming few decades. Many factors can influence THA outcome including those related to the patient and the operation. In this narrative review, we discuss the effect of patient-related factors (age, gender, socioeconomic status [SES], body mass index, and preoperative health status) on functional outcome measures, quality of life and postoperative complication. We used registry-based studies as the main source of data and found the literature to suggest that old age, female gender, low SES, worse preoperative health status, underweight or class III obesity could reduce the patient functional outcome measures and satisfaction while increasing the risk for intra-and postoperative adverse events as well as postoperative mortality rate. These findings are of value when counseling THA patients, whereby modifiable parameters such as low SES, worse preoperative health status, underweight, or class III obesity can be optimized. Other operation-related factors such as surgical approach, surgeon experience/caseload, choice of prosthetic implant, and fixation method are also important for the THA outcome and therefore should be taken into consideration. However, these factors are not included in this narrative review.

Clinical efficacy of implementing a Patient Blood Management (PBM) Protocol in joint replacement surgery: a retrospective cohort study in a national referral center.

The aging of population has dramatically broadened the total number of Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA) performed worldwide. To optimize the number of blood transfusions performed, a multimodal and multidisciplinary approach was introduced, called Patient Blood Management (PBM). The aim of the present retrospective study is to evaluate the feasibility and clinical outcomes of a PBM protocol applied in a national referral center for joint replacement surgery. Clinical reports of 9,635 patients undergoing primary THA or TKA, from 2014 to 2019, were screened. The trends of hemoglobin value at admission and at day 4 after surgery were analyzed. Furthermore, the trend of blood bags' requests and blood transfusions was longitudinally evaluated to assess the efficacy of our PBM protocol and its potential impact in reducing the length of stay in the hospital. In 2014, mean hemoglobin (Hb) levels at postoperative day 4 were 10.3 g/dl and 10.2 g/dl for TKA (unilateral and bilateral, respectively), and in 2019 were 11.3 g/dl and 11.6 g/dl (unilateral and bilateral, respectively, p=0.001). Total requested red blood cell (RBC) transfusions by each surgery over time have decreased for THA (277 in 2014 vs. 120 in 2019, p=0.001). A correlation matrix analysis between Hb level, body mass index (BMI), age, days spent in orthopedic (OR) ward and number of requested transfusions showed that RBC bags transfusions were related to the length of the hospital stay. A timely application of a PBM protocol in the perioperative period of TKA and THA was significantly associated to the reduction of blood transfusions and total length of hospital stay, with clear benefits for both the patients and the hospital.

Length doesn’t play a role – Sexual activity in men after short stem Total hip Arthroplasty

BackgroundChronic hip pain due to osteoarthritis or hip dysplasia has been shown to negatively affect many daily life aspects. One aspect, however, which persists underestimated is sexual health. The number of total hip arthroplasties (THA) are increasing, especially in young patients who have high functional expectations, not only to pain relief, but to an increase in hip mobility and quality of life as well as sexual activity.Aim(1) to report the demographic factors, (2) the sexual activity before and after THA, as well as the concerns related to sexual activity after THA and (3) the patient-reported outcome measurements (PROMs) in sexually active male patients.MethodsWe evaluated the results of patients between 18 and 65 years of age following primary cementless short femoral stem THA using a direct anterior approach (DAA) at a midterm follow-up of 4 years. A web-based questionnaire (via SurveyMonkey) was chosen to assess frequency, positions, complaints, fears, dealing with the questions and PROMs. Our patients sexual activity was via The Sexual Health Inventory for Men (SHIM) validated.ResultsPatients resumed their sexual activities after 6 weeks. The two main causes of difficulty in sexual activity before surgery were pain and limitation of the range of motion of the hip joint. Patients experienced less pain and an improvement in hip range of motion after THA. 89% of patients expressed a desire for more detailed and specific information on the subject. The patients foremost concern about muscle weakness, surgical scar or fear of dislocation. After 4 years follow-up our patients presented a significant improvement of the modified Harris Hip Score (mHHS) from 34.1 preoperative to 92.6 after THA.ConclusionTHA improves the quality in sexual life, in relation to less pain and improvement in the range of motion, but not in the frequency of sexual activity. Men’s sexual positions required less mobility and could therefore be considered safer.

Dual mobility prosthesis in Hip Arthroplasty

Background: With the increase in the number of total hip arthroplasty performed in the next decades to reduce or prevent medical and mechanical complications such as post operative THA instability Dual mobility was introduced as an alternative to standard sockets to reduce the risk of THA dislocation post operatively.(1) Aim of the work: to evaluate the hip joint function and stability after dual mobility total hip replacement using standard evaluation methods in 20 cases of hip problems. Patients and Methods: This study included 20 patients; 9 males and 11 females with a mean age 55.1 ± 14.1. All cases were identified to have one or more risk factor for dislocation after hip arthroplasty, 8 cases had previous hip surgeries, (4 hemiaarthroplasties, 2 previous THR and 2 internal fixation surgeries) and 12 cases had no previous hip surgeries. From the 20 cases 1 case was operated through posterior approach and 19 through lateral approach. Results: There were 2 complications in 2 cases, limb length discrepancy (2 cm longer in the operated side) and superficial infection, all of which are attributed to technical and patient’s factors rather than implant factor.

Patient Functional Status as an Indication for Primary Total Hip Arthroplasty: A Systematic Review and Meta-Analysis.

The number of total hip arthroplasties performed per year is increasing for reasons not fully explained by a growing and aging population. The purpose of this study was to determine the role of patient functional status as an indication for surgery and determine if patients are undergoing surgery at a better functional status than in the past. A systematic review and meta-analysis of the MEDLINE, EMBASE, and Cochrane databases was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Functional status was assessed using the 36-Item Short-Form Health Survey's Physical Component Summary score. Only primary procedures were included; revisions were excluded. Articles were screened by 2 independent reviewers with conflicts resolved with a third reviewer. Meta-regression analysis was performed to determine the effect of time, patient age, and gender. Subgroup analysis was performed to compare geographic regions. A total of 1504 articles were identified. Data from 172 groups representing 18,644 patients recruited from 1990 to 2013 and identified from 107 articles were included. The mean preoperative Physical Component Summary score was 31.2 (95% confidence interval 30.5-31.9) with a 95% prediction interval of 22.6-39.8. The variance across studies was statistically significant (P= .000) with 97.25% true variance. Year of enrollment, age, and the percentage of females were not found to have any significant effect. There were no differences between countries. Patients are undergoing total hip arthroplasty at a similar preoperative physical functional status as in the past. Patient age, gender, and location do not influence the functional status at which patients are indicated for surgery.

Evaluation of Extreme Hip Joint Movement after Total Hip Arthroplasty: A Retrospective Study

Introductions: The number of total hip arthroplasty (THA) is increased every year in our country. Mobility ofthe hip joint after THA is important to achieve. Subject’s expectation to perform daily activity, moreoverextreme hip movement are crucial for some particular populations. This study aimed to evaluate patient’s functional outcome and ability to peform extreme hip joint movement. Methods: This is a retrospective study of patients who received total hip arthroplasty in our center. Evaluated factors Include age, gender, body mass Index (BMI), socio-economic status, diagnosis, physical therapy, radiographic acetabular inclination, acetabular cup diameter, and head diameter. Clinical evaluation performed with Harris hip score (HHS). Extreme hip joint movement evaluation performed with patient’s ability to perform squatting and Salat (Muslim prayer). The chi-square and mann-whitney tests were used for data analysis. Results: We collected data from a total of 22 subjects. All patients (100%) could perform squatting postoperatively. Among the subjects, therewere 11 patients (11/22, 50%) could perform Salat activity in excellent manner, while the rest (11 patients)need some modification of movement during Salat activity. All patients have significant improvement of Harris hip score compared to preoperative condition. Further, we tried to compare factors between the two group for possible difference. No significant difference in age, gender, BMI, comorbidities, preoperative diagnosis between two group of patients. Conclusions: Subject receiving THA can be expected to perform extreme hip joint movement post-operatively. However, some patients still could not perform Salat activity in excellent manner. Age, gender, BMI, and comorbidities seem to be had no effect on the patient’s ability to performextreme hip movement post-operatively.

Hydroxyapatite-coated cementless total hip arthroplasty for patients undergoing dialysis: a study of 30 hips with a minimum follow-up period of 5\u2009years

BackgroundThe number of total hip arthroplasties (THAs) performed for patients undergoing dialysis is increasing. However, there are few reports of cementless THA for patients undergoing dialysis. This study investigated the mid-term to long-term results of hydroxyapatite (HA)-coated cementless THA for dialysis patients.MethodsThis single-center, retrospective study enrolled dialysis patients undergoing primary HA-coated cementless THA. A total of 24 patients (30 hips) were included in the final analyses. The Harris hip score and radiographic results were assessed preoperatively and during the final follow-up examination. Postoperative complications and mortality rates were recorded. The mean follow-up period was 109 months (range, 60–216 months).ResultsThe total Harris hip score significantly improved from 40 to 84 points. The overall cumulative survival rates with revision as the endpoint were 100% at 5 years and 90.4% at both 10 and 15 years. Stress shielding was observed in 24 hips (80%). No deaths were related to the primary THA. Complications included periprosthetic fracture for one patient (3.3%), blood transfusion for nine patients (30%), shunt blockage for two patients (6.7%), deep infection for one patient (3.3%), and dislocation for two patients (6.7%).ConclusionsHA-coated cementless THA resulted in good mid-term outcomes for patients undergoing dialysis with no mortality risk. However, the procedure involved a relatively high perioperative risk of blood transfusion.

Design and Evaluation of a Hip Joint Implant Wear Simulator

Abstract: Every year a high number of total hip arthroplasty is reported worldwide and an increase in this number is expected. Several factors may cause hip wear, such as osteoarthritis, obesity, traffic accidents and sport practicing. Wear is a concern when considering hip prostheses, since a prosthesis presents finite life that in many cases is shorter than patient life, and leads to substitution. Also, research is constant and new developments have to be tested, which leads to the necessity of testing devices that reproduce real conditions of hip joint implant functioning. This work describes a low-cost device, according to the ISO 12242. The equipment was built, a set of three commercially available prostheses was tested and the results show wear values coherent with those found in literature. It was found a value of wear rate of (13.30 ± 3,81) mg/106 cycles; wear factor found was (0.41 ± 0,09) x 10-6 mm3 /Nm. After testing, the device was evaluated and no component presented significant wear. Keywords: Hip joint simulator; Prostheses; Wear; Arthroplasty; Test machine.

Spinopelvic Alignment and Its Use in Total Hip Replacement Preoperative Planning-Decision Making Guide and Literature Review.

Worldwide tendencies to perform large numbers of total hip arthroplasties in the treatment of osteoarthritis are observable over a long period of time. Every year, there is an observable increase in the number of these procedures performed. The outcomes are good but not ideal, especially in groups of patients with spine problems. In recent years, a growing interest in this field may be observed, since spinopelvic alignment seems to have a significant impact on total hip replacement (THR) results. The aim of this study is to describe relations between spine and pelvic alignment and provide practical information about its impact on total hip replacement. The authors performed a literature review based on PubMed, Embase, and Medline and provide practical guidelines based on them and their own experience.

In vivo loading on the hip joint in patients with total hip replacement performing gymnastics and aerobics exercises

A further increase in the number of total hip arthroplasty (THA) is predicted, in particular the number of young THA patients has raised and with it their demands. There is no standardized evidence-based rehabilitation program and no reliable guidelines for sports activities after THA. Stretching and strengthening gymnastics are routinely performed in rehabilitation and aerobics as a sport after THA. The aim of the investigation was to determine the in vivo force and moments acting on the hip prosthesis during gymnastics and aerobic exercises to provide a source for evidence-based recommendations. Hip joint loads were measured in six patients with instrumented hip implants. The resulting force FRes, bending moment MBend at the neck and torsional moment MTors at the stem were examined during seven strengthening (with two different resistance bands) and four stretching gymnastic exercises and seven aerobic exercises with and without an aerobic step board compared to the loads during the reference activity walking. The stretching and strengthening gymnastics exercises and the aerobic exercises with and without a board demonstrated in their median peak force and moments mostly lower or similar values compared to walking. Significantly increased loads were recorded for the flexor stretching exercise in monopod stand (Fres and MBend), the strengthening abduction exercise on the chair (MTors) and the strengthening flexion exercise with the stronger resistance band (MTors). We also found a significant increase in median peak values in aerobic exercises with a board for the "Basic Step" (ipsilateral started Fres and MTors; contralateral started MTors), "Kickstep ipsilateral started" (Fres and MTors) and "Over the Top contralateral started" (Fres). The in vivo loads in THA patients during frequently performed stretching, strengthening and aerobic exercises were demonstrated for the first time. It was proved that stretching gymnastic exercises are safe in terms of resulting force, bending and torque moments for THA patients, although an external assistance for stabilization may be considered. Strengthening gymnastics exercises are reliable in terms of Fres, MBend and MTors, but, based on our data, we recommend to adhere to the communicated specific postoperative restrictions and select the resistance bands with lower tension. Aerobic exercises without an aerobic board can be considered as reliable activity in terms of force and moments for THA patients. Aerobic exercises with a board are not recommended for the early postoperative period and in our opinion need to be adapted to the individual muscular and coordinative resources.

Intersectionality of Net Worth and Race Relative to Utilization of Total Hip and Knee Arthroplasty

BackgroundAlthough the number of total hip arthroplasty and total knee arthroplasty (THA and TKA) increases, individuals of color continue to be less likely to undergo these procedures. Socioeconomic status may be a key influencer of THA and TKA utilization and outcomes. We explore the influence of net worth and race on THA and TKA utilization and outcomes of length of stay and readmissions using a large patient database. MethodsThe StrataSphere data set, an aggregation of 49 health systems representing 209 hospitals, was used for primary THA and TKA procedures performed in the calendar year 2019. Net worth was determined from Market Vue Partners’ data sources. Statistical analyses were performed to investigate relationships between net worth and patients undergoing THA or TKA. ResultsWhen comparing our overall patient cohorts with the US population using Census data, we found differences in the utilization pattern indicated by index ratios most clearly in the lowest net worth categories. In the <$10K net worth category, THA and TKA index ratios were 0.51 and 0.54, respectively. In addition, we found that patients in the $100-250 and $250-500K net worth categories had increased utilization of both THA (index ratios of 1.39, 1.53) and TKA (index ratios of 1.45, 1.47) surgeries. ConclusionNet worth is a strong driver of disparities in utilization of THA and TKA with lower utilization of these surgeries in patients with net worth <$10K and increased utilization in patients with net worth from $100-250 and $250-500K.

Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

BackgroundAll current total hip arthroplasty (THA) systems are modular in design. Only during the operation femoral head and stem get connected by a Morse taper junction. The junction is realized by hammer blows from the surgeon. Decisive for the junction strength is the maximum force acting once in the direction of the neck axis, which is mainly influenced by the applied impulse and surrounding soft tissues. This leads to large differences in assembly forces between the surgeries. This study aimed to quantify the assembly forces of different surgeons under influence of surrounding soft tissue.MethodsFirst, a measuring system, consisting of a prosthesis and a hammer, was developed. Both components are equipped with a piezoelectric force sensor. Initially, in situ experiments on human cadavers were carried out using this system in order to determine the actual assembly forces and to characterize the influence of human soft tissues. Afterwards, an in vitro model in the form of an artificial femur (Sawbones Europe AB, Malmo, Sweden) with implanted measuring stem embedded in gelatine was developed. The gelatine mixture was chosen in such a way that assembly forces applied to the model corresponded to those in situ. A study involving 31 surgeons was carried out on the aforementioned in vitro model, in which the assembly forces were determined.ResultsA model was developed, with the influence of human soft tissues being taken into account. The assembly forces measured on the in vitro model were, on average, 2037.2 N ± 724.9 N, ranging from 822.5 N to 3835.2 N. The comparison among the surgeons showed no significant differences in sex (P = 0.09), work experience (P = 0.71) and number of THAs performed per year (P = 0.69).ConclusionsAll measured assembly forces were below 4 kN, which is recommended in the literature. This could lead to increased corrosion following fretting in the head-neck interface. In addition, there was a very wide range of assembly forces among the surgeons, although other influencing factors such as different implant sizes or materials were not taken into account. To ensure optimal assembly force, the impaction should be standardized, e.g., by using an appropriate surgical instrument.

A semiautomated method to quantitatively assess osteolytic lesion volume and bone mineral density within acetabular regions of interest from CT.

The objectives of this study were to (1) develop a semiautomated method to obtain lesion volume and bone mineral density (BMD) in terms of Hounsfield units from pelvic computed tomography (CT) scans in three regions of interest, and (2) assess accuracy and reliability of the method based on cadaveric CT scans. Image artefacts due to metal implants reduce CT clarity and are more severe with more than one implant in situ. Therefore, accuracy and reliability tests were performed with varying numbers of total hip arthroplasties implanted. To test the accuracy of lesion size measurements, microcomputed tomography was used as a reference. Mean absolute error ranged from 36 to 284 mm3 after five measurements. Intra- and inter-operator reliability of the entire method was measured for a selection of parameters. All coefficient of variation values were good to excellent for CT scans of the native pelvic anatomy and a CT scans of the same pelvis with one and two implants in situ. Accuracy of quantifying lesion volume decreased with decreasing CT image clarity by 0.6%-3.6% mean absolute relative error. Reliability of lesion volume measurement decreased with decreasing CT clarity. This was also the case for reliability of BMD measurements in the region most disrupted by metal artefact. The presented method proposes an approach for quantifying bone loss which has been proven to be accurate, reliable, and clinically applicable.