Cost effectiveness analyses of total hip arthroplasty for hip osteoarthritis: A PRISMA systematic review

Trends and Themes in the Study of Value in Orthopedic Surgery: A Systematic Review

Background

The study of value in orthopedic surgery aims to maximize health outcomes gained per unit cost through various health economic tools but is fragmented across various subspecialties and geographies. Therefore, it is difficult to ascertain whether this research methodology is being used to its full potential across all orthopedic subspecialties and geographies.

Purpose

We sought to assess the distribution of prior health economics literature in orthopedic surgery across subspecialties and geographies. The secondary aim was to identify pertinent methodologic trends that may affect the conclusions drawn.

Methods

A systematic review utilizing 3 electronic databases (Medline, Embase, and Web of Science) was performed. Inclusion criteria included prior systematic reviews assessing economic analyses across all orthopedic surgery subspecialities published between 2010 and April 24, 2021. The quality of evidence was assessed using the Assessment of Multiple Systematic Review tool. Data were qualitatively analyzed.

Results

In the 44 studies included, arthroplasty (36.4%) and spine (31.8%) were the most represented subspecialties. Almost half of studies originated from the United States (45.5%), followed by the United Kingdom (18.2%). Health economic models were most commonly from the perspective of the health care or hospital system (40.5%), followed by the societal perspective (23.5%), and the payer perspective (14.8%).

Conclusions

The study of value in orthopedic surgery is not uniformly leveraged across all subspecialties and geographies. Methodologically, the societal perspective was inadequately represented, despite orthopedic pathologies often incurring significant indirect costs (eg, time off work, rehabilitation expenses).

A survey of Scottish Committee for Orthopaedics and Trauma members on lower limb joint replacement practices in morbidly obese patients

Background

Scotland has one of the highest rates of obesity in the developed world which increases risk of lower limb osteoarthritis resulting in total joint arthroplasty (TJA). This paper aimed to investigate (1) current practice of orthopaedic consultants in Scotland in managing end-stage hip and knee osteoarthritis in obese patients, (2) adherence to National guidelines, and (3) understanding of complication risks in lower limb TJA for BMI≥40.

Methods

A 15-question online survey was sent to all active members of Scottish Committee for Orthopaedics and Trauma (SCOT) between February and March 2023 to understand the current practices for managing obese patients with lower limb arthritis requiring joint replacement surgery.

Results

The survey received 62 responses from members of SCOT. The experience ranges from 1 to 44 years (mean 15 years) at consultant level. 61 % of respondents were aware of the SCOT National Guidelines for lower limb TJA in obese patients. 72 % would offer TJA to patients with a BMI>40.35 % would get a second opinion and 22 % discuss these cases in a multidisciplinary team meeting. 71 % were aware of the local weight management guidelines. 77 % quoted risk of deep infection to be between 1 and 30 %, and 40 % quoted risk of amputation between .002 % and 10 % in morbidly obese patients.

Conclusion

Surgical management of obese patients with lower limb osteoarthritis in Scotland is variable. A standardised approach would be beneficial in obtaining informed consent.

Micro-CT Assessment During Embedding of Prototype Ti Alloy Multi-Spiked Connecting Scaffold in Subchondral Trabecular Bone of Osteoarthritic Femoral Heads, Depending on Host BMI

The prototype of a biomimetic multi-spiked connecting scaffold (MSC-Scaffold) represents an essential innovation in the fixation in subchondral trabecular bone of components for a new generation of entirely cementless hip resurfacing arthroplasty (RA) endoprostheses. In designing such a functional biomaterial scaffold, identifying the microstructural and mechanical properties of the host bone compromised by degenerative disease is crucial for proper post-operative functioning and long-term maintenance of the endoprosthesis components. This study aimed to explore, depending on the occurrence of obesity, changes in the microstructure and mechanical properties of the subchondral trabecular bone in femoral heads of osteoarthritis (OA) patients caused by the MSC-Scaffold embedding. Computed microtomography (micro-CT) scanning of femoral heads from OA patients was conducted before and after the mechanical embedding of the MSC-Scaffold. Bone morphometric parameters such as bone volume/total volume (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) for regions surrounding the MSC-Scaffold were computed, and the mechanical properties such as bone density (ρB), bone compressive strength (S), and the Young's modulus (E) within these regions were calculated. A statistically significant increase in BV/TV (by 15.0% and 24.9%) and Tb.Th (by 13.1% and 42.5%) and a decrease in Tb.N (by 15.2% and 23.6%) were observed, which translates to an increase in ρB (by 15.0% and 24.9%), S (by 28.8% and 49.5%), and E (by 18.0% and 29.8%) in non-obese patients and obese patients, respectively. These changes in properties are favorable for the mechanical loads' transfer from the artificial joint surface via the MSC-Scaffold to the periarticular trabecular bone of the OA femoral head in the postoperative period.

Stepping up recovery: integrating patient reported outcome measures and wearable technology for 90-day rehabilitation following total hip arthroplasty

INTRODUCTION

There is conflicting data in the literature regarding the clinical utility of wearable devices. This study examined the association between patient reported outcome measures (PROMs) and step and stair flight counts obtained from wearable devices in postoperative total hip arthroplasty (THA) patients.

METHODS

Data was collected from a multicenter prospective longitudinal cohort study from October 2018 to February 2022. A smartphone-based platform with smartwatch was utilized for collection of daily step and stair flight counts. Subjects (N = 1644) completed the Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) and numerical rating scale (NRS) pain scores preoperatively and at 1 and 3 months postoperatively. Patients who reported living in a multi-level home (N = 931) were included in analysis of stair flight counts. Pearson correlation coefficients were calculated to determine correlations between step and stair flight counts with NRS pain and HOOS JR scores.

RESULTS

Step counts demonstrated a weak negative correlation to NRS pain scores at preoperative (r = - 0.15, p < 0.0001), 1-month (r = - 0.15, p < 0.0001), and 3-months follow-up (r = - 0.06, p = 0.05). Step counts demonstrated a weak positive correlation with HOOS JR scores at preoperative (r = 0.16, p < 0.0001), 1-month (r = 0.15, p < 0.0001), and 3-months (r = 0.13, p < 0.0001). Stair flight counts demonstrated a weak negative correlation with NRS pain preoperatively (r = - 0.19, p < 0.0001) and at 1-month (r = - 0.11, p = 0.003). Stair flight counts positively correlated with HOOS JR scores at preoperative (r = 0.24, p < 0.0001), 1-month (r = 0.15, p < 0.0001), and 3-months (r = 0.09, p = 0.02).

CONCLUSION

The utilization of wearable technology can enhance the evaluation of patient outcomes after THA, primarily due to the observed correlation between data collected from wearables and PROMs. Our study highlights the importance of the use of objective data, in addition to subjective patient reported data, when analyzing postoperative patient progress, which propels forward the field of postoperative THA patient care.

For many but not for all: the bikini incision direct anterior approach for total hip arthroplasty. A narrative review

Total hip arthroplasty (THA) has significantly improved the lives of patients with degenerative hip disorders. The direct anterior approach (DAA) is favored for its minimally invasive nature, leading to less postoperative pain and a faster recovery. The bikini incision (BI) approach was developed to enhance aesthetic outcomes while maintaining the clinical and functional benefits of the DAA. Despite its advantages, the BI technique presents challenges, controversies persist regarding its efficacy and safety, and there is no consensus within the medical community about its overall benefits. Incisions aligned with Langer's lines, like the BI, promote better healing and minimal scarring. Studies indicate that BI patients report higher satisfaction with scar appearance and texture compared to traditional DAA patients. However, the BI carries a higher risk of lateral femoral cutaneous nerve (LFCN) injury, although most symptoms resolve within 6 months. For obese patients, the BI is associated with fewer complications, such as infections and delayed healing, compared to the conventional DAA, making it a safe and effective option. BI patients also experience better aesthetic outcomes and functional recovery, with reduced pain and itching. The BI technique in THA represents a significant advancement, offering improved aesthetic and wound-healing outcomes. The shift from the traditional DAA to the BI aligns with patient preferences for scars that are less visible and conspicuous. Despite the steep learning curve and risks, careful patient selection and refined surgical techniques can enhance the BI's benefits. Future research should focus on long-term outcomes and comparative studies to further establish the BI's efficacy and safety. As patient demand for aesthetically favorable surgeries grows, the BI is likely to become a preferred approach in THA.

Patient-Level Value Analysis in Total Hip Arthroplasty: Optimizing the Value of Care Delivery

BACKGROUND

Value is defined as the ratio of patient outcomes to the cost of care. One method to assess value is through patient-level value analysis (PLVA). To our knowledge, this tool has not previously been implemented in the setting of total hip arthroplasty (THA). The purposes of this study were to perform PLVA for a 1-year episode of care among patients undergoing primary THA and to identify characteristics that affect value in a metropolitan health-care system.

METHODS

The patient-reported outcome (PRO) measure database of the institution was queried for all primary THAs from 2018 to 2019. The PRO measure that was utilized was the Hip disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS-JR). Cost was evaluated with use of time-driven activity-based costing (TDABC) for a 1-year episode of care (consisting of the day of surgery, inpatient stay, discharge facility, postoperative appointments, and physical therapy). The primary outcome was the 1-year value quotient, or the ratio of the 1-year change in HOOS-JR to the cost of the episode of care (VHOOS). The value quotient was compared among all included patients and evaluated for variables that may affect the overall value of the episode of care.

RESULTS

In total, 480 patients were included in the analysis. The mean improvement in the HOOS-JR was +34.9 ± 16.1 (95% confidence interval [CI]: 33.5, 36.3). The mean cost was $13,835 ± $3,471 (95% CI: $13,524, $14,146). The largest contributor to cost was implants (39.0%), followed by post-recovery care (i.e., inpatient stay and specialized nursing facilities; 24.1%). Change in the HOOS-JR was poorly correlated with the cost of care (r = -0.06; p = 0.19). THAs performed at an ambulatory surgery center (ASC) with discharge to home demonstrated higher value (VHOOS = 0.42) than THAs performed at a hospital with discharge to a rehabilitation facility (VHOOS = 0.15; analysis of variance F-test, p < 0.01).

CONCLUSIONS

Our study found that PROs did not correlate with costs in the setting of primary THA. Implants were the largest cost driver. Surgical setting (an ASC versus a hospital) and discharge destination influenced value as well. PLVA is a value measurement tool that can be utilized to optimize components of the care delivery pathway.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Early insights from the routine use of patient reported outcome measures in elective hip and knee arthroplasty at a public teaching hospital in South Australia

INTRODUCTION

For advanced osteoarthritis of the knee and hip, the most clinically effective treatment remains total-knee arthroplasty (TKA) and total-hip arthroplasty (THA). Success of these surgeries have traditionally been appraised by economic and volume-based measures. There has been a shift towards the use of patient reported outcome measures (PROMs) to quantify success and guide treatment. The present study provides analysis of three PROMS which have been validated for use in orthopaedic settings; the Oxford Knee Score (OKS), Oxford Hip Score (OHS), Forgotten Joint Score (FJS), and the EuroQol-Visual Analogue Scale (EQ-VAS) - a non-disease specific measure of health. PROMs were completed pre-operatively, 6-weeks, and 1-year after elective TKA and THA undertaken in 2018 in a public teaching hospital in South Australia. Post-operative satisfaction/dissatisfaction was measured using a 5-point Likert scale and was collected at the same 6-week and 1-year points.

RESULTS

PROMs were collected from 285 eligible elective knee-arthroplasty, and 205 elective hip-arthroplasty patients. There was significant average improvement, greater than minimal clinical important differences between pre-operative and 1-year post-operative scores for all three PROMs tools. Inter-PROM correlation was strongest between FJS and OKS at 1-year post TKA (rs = 0.722), and between FJS and OHS in post-THA at the same interval (rs = 0.609). TKA patients with higher pre-surgical 10-year mortality were weakly associated with lower pre-operative OKS score (rs = 0.169). BMI was weakly negatively associated with pre-operative and 6-week post-operative EQ-VAS scores (rs = -0.291 and rs = -0.149 respectively). Post-TKA satisfaction was 77.2% at 1-year, and THA 88.5% at the same interval.

CONCLUSION

This study provides an early insight from the use of the OKS, OHS, the EQ-VAS and the FJS as PROMs in primary TKA and THA at our centre. All PROMs demonstrate significant increase (improvement) at both 6-week and 1-year post-operative intervals, relative to pre-operative scores. The FJS demonstrated good sensitivity. Pre-existing co-morbidities do not appear to have any significant relation with post-operative PROMs collected in this study.

The Posterior Approach is Associated With Lower Total Encounter and 90-Day Costs When Compared to the Direct Anterior Approach

BACKGROUND

The clinical impact of the surgical approach in total hip arthroplasty (THA) has been widely reviewed. This study evaluated the total encounter and 90-day costs of THA for 2 surgical approaches (posterior [P] and direct anterior [DA]) in 1 tertiary health system.

METHODS

This is a retrospective review of 2,101 THAs (1,092 P and 1,009 DA) by 4 surgeons (2 with the highest volume of DA and P, respectively) from 2017 to 2022 at 1 academic center. Demographics, comorbidities, operative time, length of hospital stay, 90-day hospital returns, and complications were compared. The total encounter cost and 90-day postoperative cost were itemized. Multivariable regression analyses evaluated associations with increased cost at each time point.

RESULTS

The DA cohort had a higher median encounter cost ($8,348.66 versus 7,332.42, P < .01), resulting from higher intraoperative (P < .01) and radiology (P < .01) expenses. Regression analyses demonstrated the DA was independently associated with increased encounter costs (odds ratio 1.1; 95% confidence interval 1.1 to 1.1; P < .01). There was a higher incidence of 90-day emergency department visits in the DA cohort (16 versus 12%, P = .02), with a trend toward increased readmissions. There was no difference in 90-day reoperations. Median 90-day cost was higher in the DA cohort ($126.99 versus 0.00, P < .01), and regression analyses demonstrated the DA had an association with increased 90-day cost (odds ratio 2.2; 95% confidence interval 1.5 to 3.0; P < .01).

CONCLUSIONS

Despite a younger patient population, the DA was independently associated with increased encounter and 90-day costs in a single academic hospital system. This study may underestimate the cost difference, as capital costs such as specialized tables were not analyzed.

Hypothyroidism Impacts Clinical and Healthcare Utilization Outcomes After Primary Total Hip Arthroplasty

BACKGROUND

Our objective was to assess the association of hypothyroidism with outcomes of primary total hip arthroplasty (THA) overall and stratified by underlying diagnosis.

METHODS

We identified patients undergoing primary THA in a national database from 2016 to 2020. We stratified them based on primary diagnoses into hip osteoarthritis (OA; N = 1,761,960), osteonecrosis (ON; N = 78,275), traumatic fracture (N = 532,910), inflammatory arthritis (IA; N = 3,520), and "other" (N = 90,550). We identified hypothyroidism and complications using secondary diagnoses. Among 2,467,215 patients undergoing primary THA, mean age was 68 years (range, 18 to 90), and 58.3% were women. Complications codes only included initial encounters. We performed time-trends analyses and multivariable-adjusted regression analyses adjusted for demographics, expected primary payer, a comorbidity score, elective versus non-elective admission, and hospital characteristic information, with clinical and healthcare utilization outcome as endpoints.

RESULTS

Overall, hypothyroidism was significantly associated with increased LOS, total charges, non-routine discharges, blood transfusions, and prosthetic fractures. In the OA cohort, hypothyroidism was associated with increased LOS, total charges, and non-routine discharges (P < .001 for each), and blood transfusions (P = .02). Hypothyroidism was associated with increased total charges (P = .001) in the ON cohort and with increased LOS, non-routine discharge, and blood transfusion (P < .05 each) in the traumatic fracture cohort.

CONCLUSIONS

Hypothyroidism was associated with blood transfusions, prosthetic fractures, and utilization outcomes in THA patients. Tailored intervention strategies for hypothyroidism should be tested for their efficacy to improve THA peri-operative outcomes.

Risk Factors for Increased Hospital Costs for Primary Total Hip Arthroplasty

BACKGROUND

Patient medical complexity increases the cost of primary total hip arthroplasty (THA). The goal of this study was to quantify the impact of specific medical comorbidities on the real hospital cost of primary THA.

METHODS

This study consisted of a retrospective analysis of 1,222 patient encounters for Current Procedural Terminology code 27130 (primary THA) between January 2017 and March 2020 at a high-volume urban academic medical center. Patient demographics, comorbidities, and admission data were collected, and univariate and multivariate gamma regression analyses were performed to identify associations with increased costs incurred during THA admission.

RESULTS

The median total cost for THA was $30,580. Univariate analysis showed increased cost for body mass index (BMI) > 35 versus BMI < 35 ($31,739 versus 30,071; P < .05), American Society of Anesthesiologists (ASA) score 3 to 4 versus ASA 1 to 2 ($32,268 versus 30,045; P < .05), prevalence of diabetes ($31,523 versus 30,379; P < .05), congestive heart failure ($34,814 versus 30,584; P < .05), peripheral vascular disease (PVD) ($35,369 versus 30,573; P < .05), chronic pulmonary disease (CPD) ($34,625 versus 30,405; P < .05), renal disease ($31,973 versus 30,352; P < .05), and increased length of stay (r = 0.424; P < .05). Multivariate gamma regression showed that BMI > 35 (relative risk [RR] = 1.05), ASA 3 to 4 (RR = 1.07), PVD (RR = 1.29), CPD (RR = 1.13), and renal disease (RR = 1.09) were independently associated with increased THA hospital cost (P < .01). Increased costs seen in BMI > 35 versus BMI < 35 patients were largely due to hospital room and board ($6,345 versus 5,766; P = .01) and operating room costs ($5,744 versus 5,185; P < .05).

CONCLUSIONS

A BMI > 35, PVD, CPD, renal disease, and ASA 3 to 4 are associated with higher inpatient hospital costs for THA.

LEVEL OF EVIDENCE

Level III; Retrospective cohort study.

Association between physical measures of spinopelvic alignment and physical functioning with patient reported outcome measures (PROMs) after total hip arthroplasty: Protocol for systematic review and meta-analysis

INTRODUCTION

Prevalence of total hip arthroplasty (THA) has trended upwards over past decades and is projected to increase further. Optimizing outcomes after surgery is essential to avoid surgical revision and maximize outcomes. Low back pain is reported as a problem post THA. Patient-reported outcome measures (PROMs) are commonly used to evaluate THA outcomes but have limitations (e.g., ceiling effects). It is therefore important to assess a comprehensive range of outcomes. Physical outcome measures of spinopelvic alignment and physical functioning demonstrate potential value, but no evidence synthesis has investigated their association with PROMs. The objectives of this systematic review are to evaluate the association between spinopelvic alignment and physical outcome measures of physical functioning with PROMs and characteristics of low back pain after THA.

METHODS AND ANALYSIS

This protocol is aligned with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Cross-sectional and longitudinal cohort studies evaluating the association between the physical outcome measures and PROMs (any outcome measures reported) following THA by any approach/implant will be included except surface replacement and revision THA. Studies investigating THA for developmental pathology and inflammatory conditions will be excluded. A systematic search in MEDLINE (Ovid), Embase (Ovid), Scopus, Web of Science, CINAHL, and the grey literature will be carried out from inception to July 31, 2023. Two independent reviewers will evaluate eligibility of retrieved articles, extract data and assess risk of bias (NIH quality assessment tool) of included studies. A third reviewer will mediate disagreements. Random-effects meta-analyses will be conducted if studies are sufficiently homogeneous in design, population, physical measures and PROMs; reporting odds ratios and 95% confidence intervals. Where meta-analyses are not possible, a narrative synthesis will be conducted. Confidence in cumulative evidence will be assessed using a modified GRADE (Grading of Recommendations Assessment, Development, and Evaluation).

PROSPERO REGISTRATION NUMBER

PROSPERO Registration number CRD42023412744.

Orthopaedic surgeons' attitude toward physical activity for people after total hip or knee replacement: Northern vs Southern European country

BACKGROUND

Regular physical activity (PA) is a key factor of lifestyle behavior enhancing general health and fitness, especially in people after total hip or knee replacement (THR and TKR). Orthopaedic surgeons can play a primary role in advocating the benefits of an active lifestyle. Aim of the study was 1) to assess the attitude of orthopaedic surgeons towards PA for people after THR/TKR and 2) to compare the attitude between a Northern European (the Netherlands) and a Southern European (Italy) country and analyze which factors influence the attitude towards PA.

METHODS

A cross-cultural study. An (online) survey was distributed among orthopaedic surgeons in Italy and the Netherlands. Chi-square and Mann-Whitney tests were used to compare surgeons' and clinics' characteristics, and questionnaires' scores, respectively. A linear regression analysis was conducted to assess which surgeon characteristics influence attitude towards PA.

RESULTS

A cohort of 159 surgeons (103 Italians and 56 Dutch) was analyzed. The median score of overall orthopaedic surgeons' attitude towards PA was positive (57 out of 72). Dutch surgeons showed a more positive attitude compared to Italian surgeons (p < 0.01). Main difference was found in the "Physical activity concern" factor, where Italian surgeons showed more concern about the negative effects of PA on the survival of the prosthesis. The regression analyses showed that "Country" and "Type of clinic" were associated with the surgeons' attitude.

CONCLUSIONS

Overall, the orthopaedic surgeons' attitude towards PA for people with THR and TKR was positive. However, Dutch surgeons seem to be more positive compared to the Italian. The country of residence was the item that most influenced attitude. Further investigations are needed to untangle specific factors, such as cultural, socioeconomic, or contextual differences within the variable "country" that may influence orthopaedic surgeons' attitudes towards PA.

A Cost Analysis of Surgical Approach in Total Hip Arthroplasty

BACKGROUND

With pressures to decrease the financial burden of total hip arthroplasty (THA), it is imperative to understand the cost drivers of this procedure. This study evaluated operative and total encounter costs for two surgical approaches to THA-posterior (P) and direct anterior (DA).

MATERIALS AND METHODS

A total of 233 THAs (134 P and 99 DA) performed by two fellowship-trained arthroplasty surgeons from 2017 to 2022 were reviewed. Demographics, comorbidities, mobility status, operative time, length of stay, implants used, discharge location, and complications until final follow-up were recorded. Total encounter cost was collected and itemized. Multivariable regression analyses evaluated predictors of cost.

RESULTS

There were differences in age (67 years for DA and 63 years for P; P=.03), body mass index (28.0 kg/m2 for DA and 33.8 kg/m2 for P; P<.01), Elixhauser Comorbidity Index score (4.6 for DA and 5.6 for P; P=.04), and operative time (2.1 hours for DA and 1.9 hours for P; P<.01) between the two cohorts. The DA cohort trended toward shorter length of stay, with the highest percentage of patients discharged home (86.9%; P=.02). The P cohort had the lowest encounter ($9601 for DA and $9100 for P; P=.20) and intraoperative (including implant used) ($7268 for DA and $6792 for P; P<.01) costs. The DA cohort had a significantly higher cost of radiology during the encounter ($244; P<.01). Regression analysis demonstrated that length of stay and DA approach were both predictors of increased encounter cost.

CONCLUSION

The DA cohort had improved measures of health; however, this approach was associated with a higher operative cost and was predictive of increased encounter cost despite a shorter length of stay. [Orthopedics. 2024;47(3):e151-e156.].

Impact of prior spinal fusion surgery on complications and functional outcomes following total hip arthroplasty: an updated systematic review and meta-analysis

PURPOSE

This study aimed to compare the complication rates and functional outcomes between patients with and without a history of spinal fusion undergoing THA.

METHODS

A systematic search was conducted across PubMed, EMBASE, Scopus, and Cochrane databases. Studies that compared adults with and without a history of spinal fusion after primary THA were included. The methodological quality of the studies was evaluated using MINORS criteria. Meta-analyses were performed utilizing mean differences (MD), standardized mean differences (SMD), and odds ratios (OR), along with 95% confidence intervals (CI).

RESULTS

Seventeen studies involving 1,789,356 patients (31,786 in the SF group and 1,757,570 in the Non-SF group) were analyzed. The spinal fusion group exhibited significantly higher rates of dislocation (OR 2.50, 95% CI 1.78-3.52), periprosthetic fracture (OR 1.96, 95% CI 1.39-2.77), overall complications (OR 1.73, 95% CI 1.10-2.71), and revision rates (OR 1.86, 95% CI 1.74-1.99). Furthermore, within the first three months, there was an increased risk of dislocation (OR 4.38, 95% CI 1.36-14.14) and revisions (OR 3.87, 95% CI 1.63-9.18). Longer spinal fusions were significantly associated with a higher risk of dislocations (OR 0.62, 95% CI 0.53-0.71). Additionally, prior spinal fusion was linked to higher levels of pain (SMD 0.11, 95% CI 0.02-0.19) and poorer functional outcomes (MD - 0.09, 95% CI - 0.18 to - 0.00).

CONCLUSIONS

Patients with a history of spinal fusion undergoing THA exhibit increased complication rates, higher levels of pain, and greater functional limitations than those without prior fusion. These findings have significant clinical implications for optimizing perioperative care in high-risk patient populations.

The reimbursement system can influence the treatment choice and favor joint replacement versus other less invasive solutions in patients affected by osteoarthritis

PURPOSE

The aim of this study was to assess how physicians perceive the role of the reimbursement system and its potential influence in affecting their treatment choice in the management of patients affected by osteoarthritis (OA).

METHODS

A survey was administered to 283 members of SIAGASCOT (Italian Society of Arthroscopy, Knee, Upper Limb, Sport, Cartilage and Orthopaedic Technologies), a National scientific orthopaedic society. The survey presented multiple choice questions on the access allowed by the current Diagnosis-Related Groups (DRG) system to all necessary options to treat patients affected by OA and on the influence toward prosthetic solutions versus other less invasive options.

RESULTS

Almost 70% of the participants consider that the current DRG system does not allow access to all necessary options to best treat patients affected by OA. More than half of the participants thought that the current DRG system favors the choice of prosthetic solutions (55%) and that it can contribute to the increase in prosthetic implantation at the expense of less invasive solutions (54%). The sub-analyses based on different age groups, professional roles, and places of work allowed to evaluate the response in each specific category, confirming the findings for all investigated aspects.

CONCLUSIONS

This survey documented that the majority of physicians consider that the reimbursement system can influence the treatment choice when managing OA patients. The current DRG system was perceived as unbalanced in favor of the choice of the prosthetic solution, which could contribute to the increase in prosthetic implantation at the expense of other less invasive options for OA management.

The outcomes of total hip replacement in osteonecrosis versus osteoarthritis: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to compare the outcomes of THA in patients with osteonecrosis (ON) and those with osteoarthritis (OA).

METHODS

Four databases were searched from inception till December 2022 for original studies that compared the outcomes of THA in ON and OA. The primary outcome was the revision rate; the secondary outcomes were dislocation and Harris hip score. This review was conducted in line with PRISMA guidelines, and the risk of bias was assessed using the Newcastle-Ottawa scale.

RESULTS

A total of 14 observational studies with 2,111,102 hips were included, with a mean age of 50.83 ± 9.32 and 55.51 ± 8.95 for ON and OA groups, respectively. The average follow-up was 7.25 ± 4.6 years. There was a statistically significant difference in revision rate between ON and OA patients in favour of OA (OR: 1.576; 95%CI: 1.24-2.00; p-value: 0.0015). However, dislocation rate (OR: 1.5004; 95%CI: 0.92-2.43; p-value: 0.0916) and Haris hip score (HHS) (SMD: - 0.0486; 95%CI: - 0.35-0.25; p-value: 0.6987) were comparable across both groups. Further sub-analysis adjusting for registry data also showed similar results between both groups.

CONCLUSION

A higher revision rate, periprosthetic fracture and periprosthetic joint infection following total hip arthroplasty were associated with osteonecrosis of the femoral head compared with osteoarthritis. However, both groups had similar dislocation rates and functional outcome measures. This finding should be applied in context due to potential confounding factors, including patient's age and activity level.

When Do We Perform Elective Total Knee Arthroplasty? General and Demographic-Specific Trends of Preoperative Pain and Function among 10,327 Patients

Total knee arthroplasty (TKA) is the sole disease-modifying intervention for end-stage osteoarthritis. However, the temporal trends and stratification of age and patient demographics of pain and function levels at which surgeons perform TKA have not been characterized. The present investigation aimed to analyze the temporal trends of preoperative pain and functional patient-reported outcomes measures (PROMs) over the past 5 years when stratifying patient demographics. A prospective cohort of all patients who underwent primary elective TKA between January 2016 and December 2020 at a North American integrated tertiary health care system was retrospectively reviewed. The primary outcome was quarterly baseline (preoperative) pain and function PROM values before primary elective TKA. Evaluated PROMs included Knee Osteoarthritis Outcome Score (KOOS)-pain and KOOS-physical function shortform (PS) for the 5-year study period and were stratified by patient demographics (age, sex, race, and body mass index [BMI]). A total of 10,327 patients were analyzed. Preoperative pain levels remained unchanged over the study period for patients in the 45- to 64-year category (P-trend = 0.922). Conversely, there was a significant improvement in preoperative pain levels in the 65+ years group. Sex-stratified trends between males and females did not demonstrate a significant change in pre-TKA baseline pain over the study period (P-trend = 0.347 and P-trend = 0.0744). Both white and black patients demonstrated consistent KOOS-pain levels throughout the study period (P-trend = 0.0855 and P-trend = 0.626). Only white patients demonstrated improving preoperative KOOS-PS (P-trend = 0.0001), while black and "other" patients demonstrated consistent lower preoperative functional levels throughout the study period (P-trend = 0.456 and P-trend = 0.871). All BMI categories demonstrated relatively consistent preoperative KOOS-pain and KOOS-PS except for overweight and obese patients who demonstrated progressive improvement in preoperative KOOS-PS over the study period. Patients and surgeons are electing to perform primary TKA at higher levels of preoperative function. Stratification by race showed black patients did not experience a similar trend of improving function and exhibited a consistently lower functional level versus white patients. This disparity is likely to be multifactorial but may indicate underlying barriers to TKA access.

Reproducibility, criterion-related validity, and minimal clinically important difference of the stair negotiation test after total Hip arthroplasty

OBJECTIVE

To determine the reproducibility, criterion-related validity, and minimal clinically important difference (MCID) of the stair negotiation test (SNT) after total hip arthroplasty (THA).

METHODS

Sixty patients who underwent THA were included in this study. They performed the SNT and rated their difficulty in stair negotiation (question 7 of the Oxford Hip Score [OHSQ7]) before and 6 months after surgery. The SNT determined the time taken by a patient to ascend, turn around, and descend the stairs (15 cm × 4 steps) and was measured twice each time. As a measure of reproducibility, the intraclass correlation coefficient (ICC1,1) was calculated using the preoperative SNT. As an index of criterion-related validity, Spearman's rank correlation coefficient was used to evaluate the relationship between the better score of two trials in the preoperative SNT and the OHSQ7. The MCID of the SNT was calculated using the distribution-based method and the anchor-based method. The change in the OHSQ7 between before and after surgery was used as an anchor in the latter method.

RESULTS

The ICC1,1 of the SNT was 0.97. The SNT was significantly correlated with the OHSQ7 (r = 0.40, p < .05). Moreover, the anchor-based MCID of the SNT was 1.98 seconds.

CONCLUSION

The SNT is an objective assessable test of stair negotiation ability in post-THA patients that has good reproducibility and moderate criterion-related validity. Changes in the SNT beyond the MCID (1.98 seconds) represent clinically important changes in stair negotiation ability.

Early return to activity of daily living after total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Total hip arthroplasty (THA) is an orthopaedic procedure that improves the quality of life in patients suffering from hip pain related to osteoarthritis, fractures, and avascular osteonecrosis of the femoral head. Different surgical approaches can be used for THA leading to different recovery times. Because of the lowering medium age of people undergoing THA, it is important to focus on the earlier return of physiological activity after surgery.

AIM

To evaluate the best approach for THA in terms of earlier return to activity.

METHOD

Studies comparing the postoperative outcomes in patients who underwent THA through different approaches were analysed focusing on patients' self-reported outcomes, ADL score and UCLA activity score with a short follow-up.

RESULTS

A total of 1990 articles were identified in the search, and 14 met the inclusion criteria. The Review Manager software version 5.4 was used to conduct a meta-analysis to compare the direct anterior (DAA) and posterior (PA) approaches, which are the most adopted approaches. An earlier return to walk without aids and to independent ADLs were reported with DAA, but without statistical significance (respectively p = 0.06 and p = 0.10). The time to return to drive was similar among the 2 groups (p = 0.88). The return to work was faster with PA, but no statistical significance was reported (p = 0.47).

CONCLUSIONS

Further studies are needed with a larger number of patients, that present homogeneous outcomes, follow-ups and rehabilitation programmes, and that compare similar surgical approaches to assess the early return to activity of daily living after THA.

Predicting the Risk of Total Hip Replacement by Using A Deep Learning Algorithm on Plain Pelvic Radiographs: Diagnostic Study

BACKGROUND

Total hip replacement (THR) is considered the gold standard of treatment for refractory degenerative hip disorders. Identifying patients who should receive THR in the short term is important. Some conservative treatments, such as intra-articular injection administered a few months before THR, may result in higher odds of arthroplasty infection. Delayed THR after functional deterioration may result in poorer outcomes and longer waiting times for those who have been flagged as needing THR. Deep learning (DL) in medical imaging applications has recently obtained significant breakthroughs. However, the use of DL in practical wayfinding, such as short-term THR prediction, is still lacking.

OBJECTIVE

In this study, we will propose a DL-based assistant system for patients with pelvic radiographs to identify the need for THR within 3 months.

METHODS

We developed a convolutional neural network-based DL algorithm to analyze pelvic radiographs, predict the hip region of interest (ROI), and determine whether or not THR is required. The data set was collected from August 2008 to December 2017. The images included 3013 surgical hip ROIs that had undergone THR and 1630 nonsurgical hip ROIs. The images were split, using split-sample validation, into training (n=3903, 80%), validation (n=476, 10%), and testing (n=475, 10%) sets to evaluate the algorithm performance.

RESULTS

The algorithm, called SurgHipNet, yielded an area under the receiver operating characteristic curve of 0.994 (95% CI 0.990-0.998). The accuracy, sensitivity, specificity, and F1-score of the model were 0.977, 0.920, 0932, and 0.944, respectively.

CONCLUSIONS

The proposed approach has demonstrated that SurgHipNet shows the ability and potential to provide efficient support in clinical decision-making; it can assist physicians in promptly determining the optimal timing for THR.

Long-term health-related quality of life of total hip arthroplasty patients and cost-effectiveness analysis in the Japanese universal health insurance system

AIM

Total hip arthroplasty can effectively improve patients' motility with end-stage osteoarthritis. This study aimed to: (1) compare gradual changes in utility values with total hip arthroplasty and estimated values without; (2) evaluate total hip arthroplasty cost-effectiveness; and (3) evaluate cost-effectiveness by age, diagnosis, and comorbidity.

METHODS

Patients who underwent total hip arthroplasty between January 2008 and December 2009 were included. Patients completed the EuroQol preoperatively and at 1, 3, 5 and 7 years postoperatively. To derive the quality-adjusted life years gained, a utility score was obtained from the EuroQol item scores and combined with 7 years, and estimates were obtained by discounting the postoperative 1-year utility value at an annual rate of 2%-4%. Mixed-effects regression models were used to compare the estimated and the measured utility values.

RESULTS

Mean total cost was 1,921,849 yen, and quality-adjusted life years gain score was 1.746 with per cost as 1,100,715 yen. Compared with actual measurements, the estimated values from 1 to 7 years post-surgery differed significantly, and interaction was observed. Regarding age, the older the patient, the higher the cost per quality-adjusted life years. Patients with lower preoperative physical function had higher quality-adjusted life years gains, while the cost per quality-adjusted life years was lower.

CONCLUSIONS

Total hip arthroplasty was cost-effective. Compared with actual measurements, the estimated utility values from 1 to 7 years post-surgery significantly differed. Even among older patients and those with impaired preoperative physical functions, its cost was lower than patients' willingness to pay in Japan.

Catastrophic Early Failure and Fragmentation of a Modern Moderately Cross-linked Polyethylene Acetabular Liner

A 60-year-old man who underwent uncomplicated staged bilateral total hip arthroplasty for femoral head osteonecrosis presented with mechanical catching of his left total hip arthroplasty 3 years after index surgery. Radiographs revealed eccentricity of the left femoral head, concerning the failure of a modern moderately cross-linked polyethylene liner. Catastrophic polyethylene liner failure with significant wear, fragmentation, and femoral head abrasion was noted during revision surgery. The original liner and head were replaced, and the patient has exhibited no complications, pain, or difficulty ambulating 6 months postoperatively. This report highlights one potential novel mechanism for the failure of the Exactech Connexion GXL liner (Exactech Inc., Gainesville, FL), an implant recently reported to have a higher-than-expected failure rate, potentially due to insufficient packaging and increased oxidative processes.

Dual-Mobility Cups in Primary Total Hip Arthroplasty

Dual-mobility cups (DMCs) were introduced in France more than 40 years ago and are increasingly used not only in hip revision but also primary hip arthroplasty. Due to a simulated large-head articulation and increased jumping distance, DMCs can contribute to a high range of motion in the hip joint and reduce the risk of instability. Numerous studies have reported low dislocation rates and high survival rates in the mid-term follow-up. Nevertheless, long-term data, especially on primary hip replacement, remain limited, and the effect of recent designs and material innovations is still unclear. Therefore, primary DMCs are mainly proposed in patients at high risk for dislocation (i.e. pelvitrochanteric insufficiency, compromised spinopelvic mobility, neuromuscular disorders, obesity and femoral neck fractures). Based on a review of recently published studies referring to these indications, the current study discusses the advantages and disadvantages of DMCs.

Decreased burden of revision hip replacements despite substantial rise in prevalence: a register-based analysis in Finland

BACKGROUND AND PURPOSE

While the incidence of THR operations has been established, little is known about the prevalence or the ratio of the annual number of revision THRs to the total number of THRs in the general population. By combining data from nationwide registers, we calculated the annual prevalence of THRs and the revision burden caused by THR survivors in Finland.

PATIENTS AND METHODS

All primary THRs performed between 1980 and 2020 were identified from the Finnish Arthroplasty Register (FAR). Patient deaths were extracted from the Finnish Digital and Population Data Services Agency and THR revisions and removals from the FAR and the Finnish Hospital Discharge Register. We analyzed annual THR prevalence by dividing the number of THRs by the population aged 40 or older and the revision burden factor (RBF) by dividing the annual number of revisions by the total number of primary and revision THRs in the population. The proportions of bilateral implants and patients with THRs performed more than 10 years earlier (older THRs) were identified.

RESULTS

THR prevalence in Finland increased rapidly, reaching 3.6% in 2020. Between 2010 and 2020, the number of THRs increased by 50% and the prevalence of THRs by 38%. In 2020, the proportion of bilateral THRs had risen to 29% and the proportion of patients with older THRs to 36%. The RBF decreased between 1996 and 2020 from 3.1% to 1.3% (age- and sex-adjusted proportion ratio PR 0.42 [95% CI 0.39-0.45]).

INTERPRETATION

Despite the decrease in the RBF, the rapidly increasing prevalence of THRs potentially increases the number of revisits and revisions and thus poses a challenge for healthcare in the future.

Hospital Charges Are Not Associated With Episode-of-Care Costs or Complications After Total Joint Arthroplasty

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) now requires hospitals to publish charges for commonly performed procedures. This study aimed to evaluate compliance with the price transparency mandate and to determine if there is a correlation between hospital charges and episode-of-care claims costs and outcomes after total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

We identified a consecutive series of 2476 Medicare patients who underwent primary THA or TKA from 2018 to 2019 at one of 18 hospitals. Each hospital website was explored to assess compliance with the new price transparency requirements. Demographics, comorbidities, complications, and readmissions were recorded. Ninety-day episode-of-care claims costs were calculated using CMS claims data. Multivariate regression was performed to determine whether hospital charges had any association with complications, readmissions, or episode-of-care costs.

RESULTS

There was no correlation between published hospital charges and inpatient costs (r = 0.087), postacute care costs (r = 0.126), or episode-of-care costs (r = 0.131). When controlling for demographics and comorbidities, there was no association between published charges and complications (P = .433) or readmissions (P = .141). All hospitals posted some shoppable services information online, but only 7 (39%) were fully compliant by publishing all price data. Of the 11 hospitals (61%) publishing hospital THA and TKA charges, the mean charge was $48,325 (range, $12,625-$79,531).

CONCLUSION

Published charges for TKA and THA had no correlation with episode-of-care claims costs and were not associated with clinical outcomes. Despite efforts by CMS to increase price transparency, few hospitals were fully compliant, and a wide range in published charges was found.

Profound Impact of Insurance Payor and Socioeconomic Status in Total Hip Arthroplasty Outcomes: Results From a High Volume Tertiary Care Center

BACKGROUND

Dual eligible Medicare/Medicaid patients undergoing total hip arthroplasty (THA) have worse outcomes compared to other insurance payors. Prior literature fails to control for the heterogeneity of care provided amongst a large cohort of hospitals and surgeons as well as differences in patient populations treated. This study compares dual eligible THA patients and Medicaid and Medicare only THA patients at a single high volume tertiary center.

METHODS

We retrospectively reviewed patients who underwent THA for aseptic osteoarthritis of the hip over a three-year period with either Medicaid or Medicare insurance. 3,329 THA patients were included, of which 439 were Medicaid payor, 182 were dual eligible, and 2,708 were Medicare payor. Groups were compared using appropriate tests for direct comparisons and regression analysis.

RESULTS

Dual eligible patients were less likely to be white and married, and were more likely to be current smokers and have COPD, liver disease, renal disease, and human immunodeficiency virus (HIV) compared to Medicare patients. These patients also had a lower age-adjusted Charleson Comorbidity Index when compared to Medicare patients (2.4 vs 3.4, P < .001). When controlling for smoking status, age, BMI and major medical comorbidities, dual eligible and Medicaid patients had increased length of stay (LOS) (0.58, 0.66 days, P < .001), higher risk of discharge to subacute rehabilitation (RR 1.97, 3.19, P < .001), and dual eligible patients more often returned to the ED within 90 days (RR 2.74, P < .001) compared to Medicare patients.

CONCLUSION

This study supports the implementation of socioeconomic risk stratification efforts to properly evaluate value-based healthcare metrics in total hip arthroplasty patients.

The impact of surgical trainee involvement in total hip arthroplasty: a systematic review of surgical efficacy, patient safety, and outcomes

PURPOSE

Concerns persist that trainee participation in surgical procedures may compromise patient care and potentiate adverse events and costs. We aimed to analyse the potential impact and consequences of surgical trainee involvement in total hip arthroplasty (THA) procedures in terms of surgical efficacy, patient safety, and functional outcomes.

METHODS

We systematically reviewed Medline/PubMed, EMBASE, the Cochrane library, and Scopus databases in October 2021. Eligible studies reported a direct comparison between THA cases performed with and without trainee involvement.

RESULTS

Eighteen publications met our eligibility criteria and were included in our study. The included studies reported on 142,450 THAs completed on 142,417 patients. Specifically, 48,155 and 94,295 surgeries were completed with and without trainee involvement, respectively. The mean operative times for procedures with (n = 5,662) and without (n = 14,763) trainee involvement were 106.20 and 91.41 min, respectively. Mean overall complication rates were 6.43% and 5.93% for THAs performed with (n = 4842) and without (n = 12,731) trainees. Lastly, the mean Harris Hip Scores (HHS) for THAs performed with (n = 442) and without (n = 750) trainee participation were 89.61 and 86.97, respectively.

CONCLUSION

Our systematic review confirmed previous studies' reports of increased operative time for THA cases with trainee involvement. However, based on the overall similar complication rates and functional hip scores obtained, patients should be reassured concerning the relative safety of trainee involvement in THA. Future prospective studies with higher levels of evidence are still needed to reinforce the existing evidence.

When is Surgery Performed? Trends, Demographic Associations, and Phenotypical Characterization of Baseline Patient-Reported Outcomes Before Total Hip Arthroplasty

BACKGROUND

Evaluating trends and drivers of baseline patient-reported outcome measures (PROMs) is critical to understanding when patients and providers elect to undergo surgery. We aimed to assess the following: (1) 5-year trends in baseline PROMs pre-THA (total hip arthroplasty) stratified by patient determinants; (2) patient factor associated with poor preoperative hip pain/function; (3) phenotypes of combined pain/function PROMs at baseline; and (4) intersurgeon variability in PROM thresholds at surgery.

METHODS

A prospective cohort of 6,902 primary THAs was enrolled (January 2016 to December 2020). Patient/surgeon details and PROMs were collected at point of care preoperatively. Outcomes included trends (5 years; 20 quarters) in Hip disability and Osteoarthritis Outcome Score (HOOS)-Pain and HOOS-PS (Physical Function Short-Form), stratified by patient demographics. Patients were further classified into phenotype categories of above or equal to median pain/function (P+PS+); below median pain/function (P-PS-); above or equal to median pain but below median function (P+PS-); and below median pain but above or equal to median function (P-PS+).

RESULTS

Baseline HOOS-Pain was consistent across the study period (P-trend = .166), while HOOS-PS demonstrated increasing function (P-trend = .015). Such trends were appreciable in males, females, and White (P-trend < .001, each) but not Black patients (P-trend = .67). Higher odds ratio (OR) of low baseline HOOS-Pain and HOOS-PS were detected among females (HOOS-Pain: OR 1.75, 95% confidence interval [CI] 1.55-1.98, P < .001; HOOS-PS: OR 1.56, 95% CI 1.38-1.77, P < .001), Black patients (HOOS-Pain: OR 1.64, 95% CI 1.35-2.82, P < .001; HOOS-PS: OR 1.59, 95% CI 1.34-1.89, P < .001), and smokers (HOOS-Pain: OR 1.56, 95% CI 1.29-1.89, P < .001; HOOS-PS: OR 1.52, 95% CI 1.25-1.85, P < .001). The P-PS- cohort (32.4%) had lowest age (65.2 ± 11.1 years), highest body mass index (31.6 ± 6.9 kg/m²), females (64.8%), Black (15.8%), and current smokers (12.2%). There was significant intersurgeon preoperative PROM variation in HOOS-Pain and HOOS-PS (P < .001, each).

CONCLUSION

In contrast to the general population, Black patients have consistently received THA at lower functional levels throughout the 5-year period. Females, smokers, and Black patients were more likely to have poorer pain and function at THA. PROMs assessment as combined pain-function phenotypes may provide a more comprehensive interpretation of patient status preoperatively.

Risk factors for reoperation due to periprosthetic joint infection after elective total hip arthroplasty: a study of 35,056 patients using linked data of the Swedish Hip Arthroplasty Registry (SHAR) and Swedish Perioperative Registry (SPOR)

Background

In Sweden, the incidence of a prosthetic joint infection (PJI) after a planned Total Hip Arthroplasty (THA) is 1.3%, but the worldwide incidence of PJI after THA is unknown. This study explores associations between reoperation due to PJI and potential risk factors.

Methods

Primary elective THA surgery registered in both the Swedish Hip Arthroplasty Registry (SHAR) and the Swedish Perioperative Registry (SPOR) between 1 January 2015 and 31 December 2019 were included in this registry study, resulting in a total study population of 35,056 cases. The outcome variable was reoperation as the result of PJI within a year after surgery. Data were analysed using a multivariable Cox regression model.

Results

Reoperation due to PJI occurred in 460 cases (i.e., 1.3% of the study population). Each year of age increased the risk with 2% (HR 1.02 Cl 1.01, 1.03 P = < 0.001). Compared to men, women had significantly less risk for reoperation (HR 2.17 Cl 1.79, 2.53 P = < 0.001). For patients with obesity (BMI > 30), the risk increased considerably compared to underweight, normal weight, or overweight patients (HR 1.89 Cl 1.43, 2.51 P = < 0.001). The risk also increased by 6% for every 10 min of operative time (HR 1.06 Cl 1.02, 1.09 P = < 0.001). Patients having general anaesthesia had greater risk compared to those with spinal anaesthesia (HR 1.34 Cl 1.04, 1.73 P = 0.024). Finally, a lateral approach showed higher risk of reoperation than a posterior approach (HR 1.43 Cl 1.18, 1.73 P = < 0.001).

Conclusion

Recognition of the several risk factors identified in this study will be important for the perioperative management of patients undergoing THA.

The Mechanism of Metallosis After Total Hip Arthroplasty

Metallosis is defined as the accumulation and deposition of metallic particles secondary to abnormal wear from prosthetic implants that may be visualized as abnormal macroscopic staining of periprosthetic soft tissues. This phenomenon occurs secondary to the release of metal ions and particles from metal-on-metal hip implants in patients with end-stage osteoarthritis. Ions and particles shed from implants can lead to local inflammation of surrounding tissue and less commonly, very rare systemic manifestations may occur in various organ systems. With the incidence of total hip arthroplasty increasing as well as rates of revisions due to prosthesis failure from previous metal-on-metal implants, metallosis has become an important area of research. Bodily fluids are electrochemically active and react with biomedical implants. Particles, especially cobalt and chromium, are released from implants as they abrade against one another into the surrounding tissues. The body’s normal defense mechanism becomes activated, which can elicit a cascade of events, leading to inflammation of the immediate surrounding tissues and eventually implant failure. In this review, various mechanisms of metallosis are explored. Focus was placed on the atomic and molecular makeup of medical implants, the component/surgical associated factors, cellular responses, wear, tribocorrosion, joint loading, and fluid pressure associated with implantation. Current treatment guidelines for failed implants include revision surgery. An alternative treatment could be chelation therapy, which may drive future studies.

Arthroplasty is an invasive procedure which disrupts surrounding joint tissues, and can greatly perturb the joint’s immune homeostasis. In some instances, this may pose a difficult challenge to implant integration. Particles released from implants into the surrounding joint tissues activate the body’s defense mechanism, eliciting a cascade of events, which leads to biotribocorrosion and electrochemical attacks on the implant. This process may lead to the release of even more particles. Besides, implant makeup and designs, frictions between bearing surfaces, corrosion of non-moving parts with modular junctions, surgical mistakes, patient factor, comorbidities, and loosened components can alter the expected function of implants. High accumulations of these ions and particulates result in metallosis, with accompanying adverse complications. Current recommended treatment for failed prosthesis is revision surgeries. However, chelation therapy as a prophylactic intervention may be useful in future efforts but more investigation is required.

Subchondral Bone Relative Area and Density in Human Osteoarthritic Femoral Heads Assessed with Micro-CT before and after Mechanical Embedding of the Innovative Multi-Spiked Connecting Scaffold for Resurfacing THA Endoprostheses: A Pilot Study

The multi-spiked connecting scaffold (MSC-Scaffold) prototype is the essential innovation in the fixation of components of resurfacing total hip arthroplasty (THRA) endoprostheses in the subchondral trabecular bone. We conducted the computed micro-tomography (micro-CT) assessment of the subchondral trabecular bone microarchitecture before and after the MSC-Scaffold embedding in femoral heads removed during long-stem endoprosthesis total hip arthroplasty (THA) of different bone densities from 4 patients with hip osteoarthritis (OA). The embedding of the MSC-Scaffold in subchondral trabecular bone causes the change in its relative area (BA/TA, bone area/total area ratio) ranged from 18.2% to 24.7% (translating to the calculated density ρ_B relative change 11.1–14.4%, and the compressive strength S relative change 75.3–122.7%) regardless of its initial density (before the MSC-Scaffold embedding). The densification of the trabecular microarchitecture of subchondral trabecular bone due to the MSC-Scaffold initial embedding gradually decreases with the increasing distance from the apexes of the MSC-Scaffold’s spikes while the spatial extent of this subchondral trabecular bone densification ranged from 1.5 to 2.5 mm (which is about half the height of the MSC-Scaffold’s spikes). It may be suggested, despite the limited number of examined femoral heads, that: (1) the magnitude of the effect of the MSC-Scaffold embedding on subchondral trabecular bone densification may be a factor contributing to the maintenance of the MSC-Scaffold also for decreased initial bone density values, (2) the deeper this effect of the subchondral trabecular bone densification, the better strength of subchondral trabecular bone, and as consequence, the better post-operative embedding of the MSC-Scaffold in the bone should be expected.

Utilization of Healthcare Resources in Osteoarthritis: A Cost of Illness Analysis Based on Real-World Data in Italy

Purpose

Understand the demographics and clinical features of patients with osteoarthritis (OA), quantify healthcare resource utilization by OA patients, and estimate the annual direct medical costs per OA patient from a National Health Service (NHS) perspective in Italy.

Patients and Methods

Retrospective observational cohort analysis using data from electronic medical records captured by the Italian IQVIA Longitudinal Patient Database (LPD). Only direct medical costs reimbursed by the NHS were considered. Patients were included if they received at least one diagnosis of OA during the period from January 1 to December 31, 2018. Each patient was observed for 3 years: a 24-month baseline period preceding the index date, and a 12-month follow-up period starting at the index date.

Results

A total of 71,467 patients met inclusion criteria: 43.98% had not been prescribed NSAIDs/opioids, 40.76% had been prescribed NSAIDs, and 15.26% an opioid. Mean age was 71.36 years, and 68.2% of the patients were women. At least one comorbidity was present in 91.34% of the patients; 38.05% were newly diagnosed with OA. During 1-year of follow-up, 173,884 prescriptions with an associated diagnosis of OA were found: 47.36% had been prescribed an NSAID, 9.11% diclofenac, 8.30% codeine+paracetamol, and 7.32% ketoprofen. Nearly 15% of the patients had at least 1 request for a specialist visit and 23.82% had at least 1 request for exams. Orthopedic visits accounted for 60% of all specialist visits. Yearly mean costs per patient were €622, for approximately €2.5 billion per year in direct costs, considering 3.9 million patients with OA in Italy. Protheses were a major driver in annual costs: €143.45 in patients without a prosthesis and €10,090.91 in those with a joint prosthesis.

Conclusion

This real-world analysis of direct costs of care of patients with OA in Italy confirms the substantial economic burden. Direct costs dramatically increased when joint replacement was needed.