The outcome of revision total hip arthroplasty for instability.

Aims: Instability is a common indication for revision total hip arthroplasty (THA). However, even after the initial revision, some patients continue to have recurrent dislocation. The aim of this study was to assess the risk for recurrent dislocation after revision THA for instability. Methods: Between 2009 and 2019, 163 patients underwent revision THA for instability at Stanford University Medical Center. Of these, 33 (20.2%) required re-revision due to recurrent dislocation. Cox proportional hazard models, with death and re-revision surgery for periprosthetic infection as competing events, were used to analyze the risk factors, including the size and alignment of the components. Paired t-tests or Wilcoxon signed-rank tests were used to assess the outcome using the Veterans RAND 12 (VR-12) physical and VR-12 mental scores, the Harris Hip Score (HHS) pain and function, and the Hip disability and Osteoarthritis Outcome score for Joint Replacement (HOOS, JR). Results: The median follow-up was 3.1 years (interquartile range 2.0 to 5.1). The one-year cumulative incidence of recurrent dislocation after revision was 8.7%, which increased to 18.8% at five years and 31.9% at ten years postoperatively. In multivariable analysis, a high American Society of Anesthesiologists (ASA) grade (hazard ratio (HR) 2.72 (95% confidence interval (CI) 1.13 to 6.60)), BMI between 25 and 30 kg/m2 (HR 4.31 (95% CI 1.52 to 12.27)), the use of specialized liners (HR 5.39 (95% CI 1.97 to 14.79) to 10.55 (95% CI 2.27 to 49.15)), lumbopelvic stiffness (HR 6.03 (95% CI 1.80 to 20.23)), and postoperative abductor weakness (HR 7.48 (95% CI 2.34 to 23.91)) were significant risk factors for recurrent dislocation. Increasing the size of the acetabular component by > 1 mm significantly decreased the risk of dislocation (HR 0.89 (95% CI 0.82 to 0.96)). The VR-12 physical and HHS (pain and function) scores improved significantly at mid term. Conclusion: Patients requiring revision THA for instability are at risk of recurrent dislocation. Higher ASA grades, being overweight, a previous lumbopelvic fusion, the use of specialized liners, and postoperative abductor weakness are significant risk factors.

Host and microbial characteristics associated with recurrent prosthetic joint infections.

Approximately 20% of patients after resection arthroplasty and antibiotic spacer placement for prosthetic joint infection develop repeat infections, requiring an additional antibiotic spacer before definitive reimplantation. The host and bacterial characteristics associated with the development of recurrent infection is poorly understood. A case-control study was conducted for 106 patients with intention to treat by two-stage revision arthroplasty for prosthetic joint infection at a single institution between 2009 and 2020. Infection was defined according to the 2018 Musculoskeletal Infection Society criteria. Thirty-nine cases ("recurrent-periprosthetic joint infection [PJI]") received at least two antibiotic spacers before clinical resolution of their infection, and 67 controls ("single-PJI") received a single antibiotic cement spacer before infection-free prosthesis reimplantation. Patient demographics, McPherson host grade, and culture results including antibiotic susceptibilities were compared. Fifty-two (78%) single-PJI and 32 (82%) recurrent-PJI patients had positive intraoperative cultures at the time of their initial spacer procedure. The odds of polymicrobial infections were 11-fold higher among recurrent-PJI patients, and the odds of significant systemic compromise (McPherson host-grade C) were more than double. Recurrent-PJI patients were significantly more likely to harbor Staphylococcus aureus. We found no differences between cases and controls in pathogen resistance to the six most tested antibiotics. Among recurrent-PJI patients, erythromycin-resistant infections were more prevalent at the final than initial spacer, despite no erythromycin exposure. Our findings suggest that McPherson host grade, polymicrobial infection, and S. aureus infection are key indicators of secondary or persistent joint infection following resection arthroplasty and antibiotic spacer placement, while bacterial resistance does not predict infection-related arthroplasty failure.

An External Acetabular Alignment Guide Decreases Positional Variance.

INTRODUCTION: Certain patient and operative factors limit accurate estimation of acetabular component positioning during total hip arthroplasty (THA). This study aimed to determine whether an intraoperative external alignment guide decreases variance in acetabular component positioning. MATERIALS AND METHODS: Adult patients who underwent primary THA from 2014-2018 were reviewed. Exclusion criteria were navigation, robot-assisted surgery, and inflammatory, post-traumatic, or avascular arthritis. One surgeon used an external guide while the second surgeon resected osteophytes and utilized available anatomical landmarks for positioning. Anteversion and inclination, variance, "safe zone" positioning, operative time, and hip instability were assessed. Multivariable regression models were used to examine effects on primary and secondary outcomes. RESULTS: 409 patients were included, of which 182 underwent component placement with landmarks only. Patients undergoing component placement with landmarks only were younger (p=0.002) and more often smokers (p=0.016). After multivariable risk adjustment, use of the external alignment guide was independently associated with 2.7° higher anteversion (CI: 1.6° to 3.8°) and smaller anteversion variance (-0.3, CI: -0.6 to 0.1) compared to landmarks only. It was independently associated with 3.2° higher inclination (CI: 2.0° to 4.4°), but there was no difference in inclination variance (-0.1, CI: -0.3 to 0.2). The external alignment guide was independently associated with a 14-minute shorter operative time (CI: 9.6 to 18.7) and smaller operative time variance (-0.9, CI: -1.2 to 0.6). DISCUSSION: Use of anatomical landmarks alone was associated with increased likelihood of safe zone positioning but lower precision and longer operative time. While this study was limited by lack of randomization and its retrospective nature, an acetabular positioner may be preferable to palpable or visible anatomy alone for acetabular component placement.

Endoscopic iliopsoas lengthening for treatment of recalcitrant iliopsoas tendinitis after total hip arthroplasty.

Iliopsoas (IP) tendinitis from impingement upon the acetabular component after total hip arthroplasty (THA) has been treated with open and endoscopic IP tenotomy or acetabular component revision. This study describes the results of a consecutive series of patients treated with endoscopic IP tenotomy as a less invasive alternative. Twenty-eight patients with IP impingement after THA underwent endoscopic IP lengthening from 2012 to 2021 at a single-center academic institution. The follow-up of 24 of these patients was achieved with a mean follow-up of 7.6 months (range 1-28). Outcomes included the modified Harris Hip Score (mHHS), visual analog pain scale (VAS), satisfaction, component positioning and complications. Seventy-one percent of patients were satisfied or very satisfied after their operation. The median mHHS preoperatively was 57 (Interquartile range [IQR] 43-60) and postoperatively was 75 (IQR 66-92, P < 0.001). Clinically meaningful improvements in mHHS were seen in patients with VAS pain scores <5, cup prominence >8 mm, body mass index >30, and less than 2 years from their index THA. Two patients developed a deep infection 7 and 10 months postoperatively (neither related to the release), and one patient underwent open psoas release for persistent impingement. Endoscopic IP tenotomy is a safe and effective treatment for impingement after THA. Patients with cup prominence >8 mm, body mass index >30 and less than 2 years since their index THA may have more clinically meaningful improvements in pain and function.

Risk Should Not Be a "Four-Letter Word" in Healthcare. Risk and the Future of Musculoskeletal Care.

Orthopaedics has seen a rapid transition to value-based care. As we transition away from fee-for-service models, healthcare systems, groups, and surgeons are being asked to take on an increasing amount of risk. While on the surface risk may have a negative connotation, managing risk allows surgeons to maintain autonomy while taking on value-based care to the next level. The purpose of this paper, the first in a series of 2, is to walk through the impact that value-based care has had on musculoskeletal surgeons, to understand the continued movement healthcare is making into risk sharing models, and to introduce the concept of surgeon specialist-led care.

Gap Balancing Throughout the Arc of Motion With Navigated TKA and a Novel Force-Controlled Distractor: A Review of the First 273 Cases.

BACKGROUND: This study evaluated the ability to achieve the targeted soft-tissue balance in terms of medio-lateral (ML) laxity and gap values when using a computer-assisted orthopedic surgery (CAOS) system featuring an intra-articular force-controlled distractor and assessed learning curves associated with the adoption of this technology. METHODS: The first 273 cases using this technology were reported without exclusions comparing 1) final ML laxity and 2) final average gap to their predefined targets. For both parameters, the signed and unsigned differentials were reported. The linear mixed model was used to evaluate laxity curve differences between surgeons. A cumulative sum control chart (CUSUM) was applied to assess surgeon learning curves regarding surgical time. RESULTS: Both the average signed ML laxity and gap differentials were neutral throughout the full arc of motion. Both the average unsigned ML laxity and gap differentials were linear. Signature of ML laxity and gap differential curves tended to be surgeon-specific. The CUSUM analyses of surgical times demonstrated either a short learning curve or the absence of a discernible learning pattern for surgeons. CONCLUSION: Data from all users involved with the pilot release of the balancing device were considered to capture variability in familiarity with the technique and learning curve cases were included. A high ability to achieve targeted gap balance throughout the arc of motion using the proposed method was observed.

Assessment of Team Dynamics and Operative Efficiency in Hip and Knee Arthroplasty.

Importance: Surgical team communication is a critical component of operative efficiency. The factors underlying optimal communication, including team turnover, role composition, and mutual familiarity, remain underinvestigated in the operating room. Objective: To assess staff turnover, trainee involvement, and surgeon staff preferences in terms of intraoperative efficiency. Design, Setting, and Participants: Retrospective analysis of staff characteristics and operating times for all total joint arthroplasties was performed at a tertiary academic medical center by 5 surgeons from January 1 to December 31, 2018. Data were analyzed from May 1, 2021, to February 18, 2022. The study included cases with primary total hip arthroplasties (THAs) and primary total knee arthroplasties (TKAs) comprising all primary total joint arthroplasties performed over the 1-year study interval. Exposures: Intraoperative turnover among nonsurgical staff, presence of trainees, and presence of surgeon-preferred staff. Main Outcomes and Measures: Incision time, procedure time, and room time for each surgery. Multivariable regression analyses between operative duration, presence of surgeon-preferred staff, and turnover among nonsurgical personnel were conducted. Results: A total of 641 cases, including 279 THAs (51% female; median age, 64 [IQR, 56.3-71.5] years) and 362 TKAs (66% [238] female; median age, 68 [IQR, 61.1-74.1] years) were considered. Turnover among circulating nurses was associated with a significant increase in operative duration in both THAs and TKAs, with estimated differences of 19.6 minutes (SE, 3.5; P < .001) of room time in THAs and 14.0 minutes (SE, 3.1; P < .001) of room time in TKAs. The presence of a preferred anesthesiologist or surgical technician was associated with significant decreases of 26.5 minutes (SE, 8.8; P = .003) of procedure time and 12.6 minutes (SE, 4.0; P = .002) of room time, respectively, in TKAs. The presence of a surgeon-preferred vendor was associated with a significant increase in operative duration in both THAs (26.3 minutes; SE, 7.3; P < .001) and TKAs (29.6 minutes; SE, 9.6; P = .002). Conclusions and Relevance: This study found that turnover among operative staff is associated with procedural inefficiency. In contrast, the presence of surgeon-preferred staff may facilitate intraoperative efficiency. Administrative or technologic support of perioperative communication and team continuity may help improve operative efficiency.

Objective Activity Parameters Track Patient-specific Physical Recovery Trajectories After Surgery and Link With Individual Preoperative Immune States.

OBJECTIVE: The longitudinal assessment of physical function with high temporal resolution at a scalable and objective level in patients recovering from surgery is highly desirable to understand the biological and clinical factors that drive the clinical outcome. However, physical recovery from surgery itself remains poorly defined and the utility of wearable technologies to study recovery after surgery has not been established. BACKGROUND: Prolonged postoperative recovery is often associated with long-lasting impairment of physical, mental, and social functions. Although phenotypical and clinical patient characteristics account for some variation of individual recovery trajectories, biological differences likely play a major role. Specifically, patient-specific immune states have been linked to prolonged physical impairment after surgery. However, current methods of quantifying physical recovery lack patient specificity and objectivity. METHODS: Here, a combined high-fidelity accelerometry and state-of-the-art deep immune profiling approach was studied in patients undergoing major joint replacement surgery. The aim was to determine whether objective physical parameters derived from accelerometry data can accurately track patient-specific physical recovery profiles (suggestive of a 'clock of postoperative recovery'), compare the performance of derived parameters with benchmark metrics including step count, and link individual recovery profiles with patients' preoperative immune state. RESULTS: The results of our models indicate that patient-specific temporal patterns of physical function can be derived with a precision superior to benchmark metrics. Notably, 6 distinct domains of physical function and sleep are identified to represent the objective temporal patterns: ''activity capacity'' and ''moderate and overall activity (declined immediately after surgery); ''sleep disruption and sedentary activity (increased after surgery); ''overall sleep'', ''sleep onset'', and ''light activity'' (no clear changes were observed after surgery). These patterns can be linked to individual patients preopera-tive immune state using cross-validated canonical-correlation analysis. Importantly, the pSTAT3 signal activity in monocytic myeloid-derived suppressor cells predicted a slower recovery. CONCLUSIONS: Accelerometry-based recovery trajectories are scalable and objective outcomes to study patient-specific factors that drive physical recovery.

High Prevalence of Spinopelvic Risk Factors in Patients With Post-Operative Hip Dislocations.

BACKGROUND: Excessive standing posterior pelvic tilt (PT), lumbar spine stiffness, low pelvic incidence (PI), and severe sagittal spinal deformity (SSD) have been linked to increased dislocation rates. We aimed to determine the prevalence of these 4 parameters in a cohort of unstable total hip arthroplasty (THA) patients and compare these to a large representative control population of primary THA patients. METHODS: Forty-eight patients with instability following primary THA were compared to a control cohort of 9414 THA patients. Lateral X-rays in standing and flexed-seated positions were used to assess PT and lumbar lordosis (LL). Computed tomography scans were used to measure PI and acetabular cup orientation. Thresholds for "at risk" spinopelvic parameters were standing posterior PT ≤ -15°, lumbar flexion (LLstand-LLseated) ≤ 20°, PI ≤ 41°, PI ≥ 70°, and SSD (PI-LLstand mismatch ≥ 20°). RESULTS: There were significant differences in mean spinopelvic parameters between the dislocating and control cohorts (P < .001). There were no differences in mean PI (58° versus 56°, respectively, P = .29) or prevalence of high and low PI between groups. 67% of the dislocating patients had one or more significant risk factors, compared to only 11% of the control. A total of 71% of the dislocating patients had cup orientations within the traditional safe zone. CONCLUSION: Excessive standing posterior PT, low lumbar flexion, and a severe SSD are more prevalent in unstable THAs. Pre-op screening for these parameters combined with appropriate planning and implant selection may help identify at risk patients and reduce the prevalence of dislocation.

Revision Hip Arthroplasty Using a Modular, Cementless Femoral Stem: Long-Term Follow-Up.

BACKGROUND: As the number of primary total hip arthroplasty (THA) cases increase, so does the demand for revision operations. However, long-term follow-up data for revision THA is lacking. METHODS: A retrospective review was completed of patients who underwent revision THA at a single institution between January 2002 and October 2007 using a cementless modular stem. Patient demographic, clinical, and radiographic data was collected. Preoperative and postoperative patient-reported outcome scores were compared at a minimum of fourteen-year follow-up. RESULTS: Eighty-four patients (89 hips) with a median age of 69 years (range, 28 to 88) at operation were included. Indications for revision included aseptic loosening (84.2%), infection (12.4%), and periprosthetic fracture (3.4%). Twenty-two hips sustained at least 1 complication: intraoperative fracture (7.9%), dislocation (6.7%), prosthetic joint infection (4.5%), deep venous thrombosis (3.4%), and late periprosthetic fracture (2.2%). There were no modular junction complications. Eight patients underwent reoperations; only three involved the stem. Thirty-eight patients (45%) were deceased prior to final follow-up without known reoperations. Twenty-seven patients (32%) were lost to follow-up. Twenty-one patients (23%) were alive at minimum fourteen-year follow-up. Complete patient-reported outcomes were available for nineteen patients (range, 14 to 18.5 years of follow-up). Significant improvement was seen in UCLA activity, VR-12 physical, hip disability and osteoarthritis outcome score, joint replacement., and Harris Hip score pain and function scores. CONCLUSION: Challenges of long-term follow-up include patient migration, an unwillingness to travel for re-examination, medical comorbidities, advanced age, and death. The cementless modular revision stem demonstrated long-term clinical success and remains a safe and reliable option for complex revision operations.

Outcome of the Wagner Cone femoral component for difficult anatomical conditions during total hip arthroplasty.

PURPOSE: Total hip arthroplasty (THA) in patients with small or unusual proximal femoral anatomy is challenging due to sizing issues, control of version, and implant fixation. The Wagner Cone is a monoblock, fluted, tapered stem with successful outcomes for these patients; however, there is limited information on subsidence, a common finding with cementless stems. METHODS: We retrospectively reviewed our cases using the modified Wagner Cone (Zimmer, Warsaw, IN) implanted over a 13-year period (2006-2019) in patients with small or abnormal proximal femoral anatomy. We performed 144 primary THAs in 114 patients using this prosthesis. Mean follow-up was 4.5 ± 3.4 years (range, 1-13 years). Common reasons for implantation were hip dysplasia (52%) and osteoarthritis in patients with small femoral proportions (22%). Analysis of outcomes included assessment of stem subsidence and stability. RESULTS: Survival was 98.6% in aseptic cases; revision-free survival was 97.9%. Femoral subsidence occurred in 84 cases (58%). No subsidence progressed after 3 months. Of those that subsided, the mean distance was 2.8 ± 2.0 mm. There was less subsidence in stems that stabilized prior to six weeks (2.2 ± 1.4 mm) compared to those that continued until 12 weeks (3.9 ± 1.6, p = 0.02). Harris Hip, UCLA, and WOMAC scores significantly improved from pre-operative evaluation (p < 0.001*, p < 0.003*, p ≪ 0.001*); there was no difference in outcome between patients with and without subsidence (p = 0.430, p = 0.228, p = 0.147). CONCLUSION: The modified Wagner Cone demonstrates excellent clinical outcomes in patients with challenging proximal femoral anatomy. Subsidence is minor, stops by 3 months, and does not compromise clinical outcome.

Isolated Versus Full Component Revision in Total Knee Arthroplasty for Aseptic Loosening.

BACKGROUND: Revision of both femoral and tibial components of a total knee arthroplasty (TKA) for aseptic loosening has favorable outcomes. Revision of only one loose component with retention of others has shorter operative time and lower cost; however, implant survivorship and clinical outcomes of these different operations are unclear. METHODS: Between January 2009 and December 2019, a consecutive cohort of revision TKA was reviewed. Univariate and multivariable analyses were used to study correlations among factors and surgical related complications, time to prosthesis failure, and functional outcomes (University of California Los Angeles, Knee Society functional, knee osteoarthritis and outcome score for joint replacement, Veterans RAND 12 (VR-12) physical, and VR-12 mental). RESULTS: A total of 238 patients underwent revision TKA for aseptic loosening. The mean follow-up time was 61 months (range 25 to 152). Ten of the 105 patients (9.5%) who underwent full revision (both femoral and tibial components) and 18 of the 133 (13.5%) who underwent isolated revision had subsequent prosthesis failure [Hazard ratio (HR) 0.67, P = .343]. The factor analysis of type of revision (full or isolated revision) did not demonstrate a significant difference between groups in terms of complications, implant failures, and times to failure. Metallosis was related to early time to failure [Hazard ratio 10.11, P < .001] and iliotibial band release was associated with more complications (Odds ratio 9.87, P = .027). Preoperative symptoms of instability were associated with the worst improvement in University of California Los Angeles score. Higher American Society of Anesthesiologists status and higher Charlson Comorbidity Index were related with worse VR-12 physical (-30.5, P = .008) and knee osteoarthritis and outcome score for joint replacement (-4.2, P = .050) scores, respectively. CONCLUSION: Isolated and full component revision TKA for aseptic loosening does not differ with respect to prosthesis failures, complications, and clinical results at 5 years. Poor American Society of Anesthesiologists status, increased comorbidities, instability, and a severe bone defect are related to worse functional improvement. LEVEL OF EVIDENCE: III, cohort with control.

The Impact of Exchanging Cerclage Fixation after Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty for Periprosthetic Joint Infection.

BACKGROUND: An extended trochanteric osteotomy (ETO) is a powerful tool for femoral component revision. There is limited evidence that directly supports its use in the setting of a periprosthetic joint infection (PJI). Cerclage fixation raises the theoretical concern for persistent infection. METHODS: Our institutional database included 76 ETOs for revision hip arthroplasty between January 1, 2008 and December 31, 2019. The cohort was divided based on indication for femoral component revision: PJI versus aseptic revision. The PJI group was subdivided based on second-stage exchange versus retention of initial cerclage fixation. Operative time, estimated blood loss, complications, and rate of repeat revision surgery were evaluated. RESULTS: Forty-nine patients (64%) underwent revision for PJI and 27 patients (36%) underwent aseptic revision. There was no significant difference in operative times (P = .082), postoperative complications (P = .258), or rate of repeat revision surgery (P = .322) between groups. Of the 49 patients in the PJI group, 40 (82%) retained cerclage fixation while 9 (18%) had cerclage exchange. Cerclage exchange did not significantly impact operative time (P = .758), blood loss (P = .498), rate of repeat revision surgery (P = .302), or postoperative complications (P = .253) including infection (P = .639). CONCLUSION: An ETO remains a powerful tool for femoral component removal, even in the presence of a PJI. A multi-institutional investigation would be required to validate observed trends toward better infection control with cerclage exchange. Cerclage exchange did not appear to increase operative time, blood loss, or postoperative complication rates.

State-Based and National U.S. Registries: The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI), California Joint Replacement Registry (CJRR), and American Joint Replacement Registry (AJRR).

ABSTRACT: The concept of a total joint registry as a tool to gather and compare longitudinal clinical outcome data emerged in the early 1970s; although initially begun as a single-institution effort, it soon spread to the development of large nationwide registries, first in Scandinavia and subsequently around the world. These national registries established the value of population-wide results, large cohorts, and the importance of ongoing implant surveillance efforts, as detailed elsewhere in this series. In the United States, concerted efforts to establish a national total joint registry for the hip and knee began in earnest in the early 2000s and culminated with the incorporation of the American Joint Replacement Registry (AJRR) in 2009. Parallel efforts soon followed to establish state-based total joint registries, either as stand-alone entities or in affiliation with the AJRR. Some of these state-based efforts succeeded, and some did not.In the first section of this article, Brian Hallstrom, MD, details the highly successful Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI). This state-based effort was made possible by a unique partnership between a single dominant statewide private payer and the Michigan orthopaedic surgery community; it has already successfully advanced the quality of care for patients in Michigan, and efforts are ongoing.The second section, by James I. Huddelston, MD, details a different path to the establishment of a focused state-based registry. The California Joint Replacement Registry (CJRR) was the result of a partnership with representatives of the statewide business community and resulted in a pioneering effort to successfully collect and publicly report patient-reported outcome measures as part of the registry data set. Further discussed are the establishment, development, and status of the AJRR and its current place among the family of American Academy of Orthopaedic Surgeons (AAOS) registries, which were inspired by the AJRR and span a range of orthopaedic specialties.

A Physician Assistant Is Associated With Higher Patient Satisfaction With Outpatient Orthopedic Surgery.

Patient satisfaction is increasingly used to assess the quality of care and determine physician reimbursement. Patient characteristics influence patient satisfaction, but the effect of physician practice parameters on satisfaction has not been studied in detail. Outpatient satisfaction scores from 11,059 patients who rated 24 orthopedic surgeons from a single institution were studied. Practice-related parameters were collected in a provider-reported survey. Univariate logistic regressions were used to test the associations between each provider characteristic and the likelihood of receiving a 5-star rating on a selection of 16 Press Ganey patient satisfaction questions. The presence of a physician assistant in the clinic positively affected the 5-star rating for all but 1 of the patient satisfaction questions examined, including overall satisfaction (odds ratio [OR], 1.38; 95% CI, 1.03-1.85; P=.031); the likelihood of being recommended to others (OR, 1.57; 95% CI, 1.16-2.14; P=.004); and friendliness/courtesy (OR, 1.58; 95% CI, 1.17-2.13; P=.003). However, having a fellow or nurse practitioner in the clinic, treating children, productivity (measured as total relative value units), taking trauma call, and provider distance from home were not associated with higher scores for any of the Press Ganey patient satisfaction questions. Having a physician assistant in the clinic is an actionable, practice-specific characteristic that positively affects patient satisfaction on many levels and may ultimately improve the perception of care. [Orthopedics. 2022;45(5):e252-e256.].

Imageless Computer Navigation Reduces 5-Year All-Cause Revision Rates After Primary Total Knee Arthroplasty.

BACKGROUND: The use of surgical navigation has been shown to reduce revision rates after total knee arthroplasty (TKA) in patients <65 years of age. It is unknown if this benefit extends to older patients. We hypothesized that the use of surgical navigation would reduce rates of all-cause revision in patients of all ages. METHODS: In this cohort study, we queried the Truven MarketScan all-payer database to identify patients who underwent TKA from 2007 to 2015. Current Procedural Terminology codes were used to create 2 groups based on whether intraoperative navigation was used. Demographics, comorbidities, complications, and revision rates were determined. International Classification of Diseases codes were used to determine reasons for revision. RESULTS: The conventional TKA cohort included 312,173 patients. The navigation cohort included 20,881 patients. There were not any clinically significant differences in demographics between the cohorts. All-cause revision rates were lower in the navigation cohort at 1 year (0.4% vs 0.5%, P = .04), 2 years (0.7% vs 0.9%, P = .003), and 5 years (0.9% vs 1.3%, P < .001) of follow-up. Revisions for mechanical loosening were more common in the conventional cohort (30.8% vs 21.9%, P = .009). Rates of revision for other causes, including infection, did not differ between groups, with the numbers available. CONCLUSION: The use of surgical navigation yielded a 30.7% reduction in the all-cause revision rate at 5-year follow-up compared to conventional TKA. This benefit increased as follow-up duration increased. Increased usage of this inexpensive technology, from the current 6.3% in this US cohort, may reduce healthcare costs. LEVEL OF EVIDENCE: III.

The Effect of Femoral Fixation on Revision and Mortality Following Elective Total Hip Arthroplasty in Patients Over the Age of 65 years. An Analysis of the American Joint Replacement Registry.

BACKGROUND: With the overwhelming use of cementless femoral fixation for primary total hip arthroplasty in the United States, the associations of stem fixation on the risk of revision and mortality are poorly understood. We evaluated the relationship between femoral fixation and risk of revision and mortality in patients included in the American Joint Replacement Registry. METHODS: Elective, primary, unilateral total hip arthroplasties in the American Joint Replacement Registry, in patients over the age of 65 years were considered. In total, 9,612 patients with a cemented stem were exact matched 1:1 with patients who received a cementless stem based on age, gender, and the Charlson Comorbidity Index. Outcomes compared between the groups included need and reason for revision at 90 days and 1 year; in-hospital, 90-day, and 1-year mortality; and mortality after early revision. Covariates were used in linear regression analyses. RESULTS: Cemented fixation was associated with a 37% reduction in the risk of 90-day revision, and a reduction in the risk of revision for periprosthetic fracture of 87% at 90 days and 81% at 1 year. Cemented fixation was associated with increased 90-day and 1-year mortality (odds ratio [OR] 3.15, confidence interval [CI] 2.24-4.43 and OR 2.36, CI 1.86-3.01, respectively). Patients who underwent subsequent revision surgery within the first year exhibited the highest mortality risk (OR 3.23, CI 1.05-9.97). CONCLUSION: In this representative sample of the United States, 90-day revision for any reason and for periprosthetic fracture was significantly reduced in patients with a cemented stem. This benefit must be weighed against the association with increased mortality and with the high risk of mortality associated with early revision, which was more prevalent with cementless fixation.

Return to work and productivity loss after surgery: A health economic evaluation.

BACKGROUND: We aimed to identify preoperative psychosocial factors associated with return-to-work (RTW) and the associated cost of productivity loss due to work absenteeism following surgery. Research demonstrates a high economic burden from productivity loss after surgery, but the comparative cost of productivity loss relative to income across different operations has not been examined. MATERIALS AND METHODS: A mixed surgical cohort recruited for a randomized controlled trial were prospectively followed for up to two years following surgery with daily phone assessments to three months, weekly assessments thereafter to six months, then monthly assessments thereafter to determine RTW status, opioid use and pain. RESULTS: 183 of 207 (88.3%) patients in paid employment prior to surgery, who provided at least one day of follow-up, were included in this analysis. The average cost of productivity loss due to work absenteeism was $13 761 (median $9064). Patients who underwent total knee replacement incurred the highest income loss. Medical claims filed before surgery were significantly associated with relative income loss (AOR 5.09; 95% CI 1.73-14.96; p < 0.01) and delayed postoperative RTW. Elevated preoperative PTSD symptoms were associated with delayed RTW (HR 0.78; 95%CI 0.63-0.96; p-value = 0.02) while male gender (HR 1.63; 95%CI 1.11-2.38; p-value = 0.01) was associated with faster postoperative RTW. CONCLUSION: Surgery places a high economic burden on individuals due to postoperative productivity loss. Multidisciplinary approaches, such as pathways, that facilitate the operation and recovery may mitigate the economic consequences for patients, employers, and the healthcare system.

Cementless Fixation Is Associated With Increased Risk of Early and All-Time Revision After Hemiarthroplasty But Not After THA for Femoral Neck Fracture: Results From the American Joint Replacement Registry.

BACKGROUND: Despite ample evidence supporting cemented femoral fixation for both hemiarthroplasty and THA for surgical treatment of displaced femoral neck fractures, cementless fixation is the preferred fixation method in the United States. To our knowledge, no nationally representative registry from the United States has compared revision rates by fixation for this surgical treatment. QUESTION/PURPOSE: After controlling for relevant confounding variables, is femoral fixation method (cemented or cementless) in hemiarthroplasty or THA for femoral neck fracture associated with a greater risk of (1) all-cause revision or (2) revision for periprosthetic fracture? METHODS: Patients with Medicare insurance who had femoral neck fractures treated with hemiarthroplasty or THA reported in the American Joint Replacement Registry database from 2012 to 2017 and Centers for Medicare and Medicaid Services claims data from 2012 to 2017 were analyzed in this retrospective, large-database study. Of the 37,201 hemiarthroplasties, 42% (15,748) used cemented fixation and 58% (21,453) used cementless fixation. Of the 7732 THAs, 20% (1511) used cemented stem fixation and 80% (6221) used cementless stem fixation. For both the hemiarthroplasty and THA cohorts, most patients were women and had cementless femoral fixation. Early revision was defined as a procedure that occurred less than 90 days from the index procedure. All patients submitted to the registry were included in the analysis. Patient follow-up was limited to the study period. No patients were lost to follow-up. Due to inherent limitations with the registry, we did not compare medical complications, including deaths attributed directly to cemented fixation. A logistic regression model including the index arthroplasty, age, gender, stem fixation method, hospital size, hospital teaching affiliation, and Charlson comorbidity index score was used to determine associations between the index procedure and revision rates. RESULTS: For the hemiarthroplasty cohort, risk factors for any revision were cementless stem fixation (odds ratio 1.42 [95% confidence interval 1.20 to 1.68]; p < 0.001), younger age (OR 0.96 [95% CI 0.95 to 0.97]; p < 0.001), and higher Charlson comorbidity index (OR 1.06 [95% CI 1.02 to 1.11]; p = 0.004). Risk factors for early revision were cementless stem fixation (OR 1.77 [95% CI 1.43 to 2.20]; p < 0.001), younger age (OR 0.98 [95% CI 0.97 to 0.99]; p < 0.001), and higher Charlson comorbidity index (OR 1.09 [95% CI 1.04 to 1.15]; p < 0.001). Risk factors for revision due to periprosthetic fracture were cementless fixation (OR 6.19 [95% CI 3.08 to 12.42]; p < 0.001) and higher Charlson comorbidity index (OR 1.16 [95% CI 1.06 to 1.28]; p = 0.002). Risk factors for early revision due to periprosthetic fracture were cementless fixation (OR 7.38 [95% CI 3.17 to 17.17]; p < 0.001), major teaching hospital (OR 2.10 [95% CI 1.08 to 4.10]; p = 0.03), and higher Charlson comorbidity index (OR 1.20 [95% CI 1.09 to 1.33]; p < 0.001). For the THA cohort, there were no associations. CONCLUSION: These data suggest that cemented fixation should be the preferred technique for most patients with displaced femoral neck fractures treated with hemiarthroplasty. The fact that stem fixation method did not affect revision rates for those patients with displaced femoral neck fractures treated with THA may be due to current practice patterns in the United States. LEVEL OF EVIDENCE: Level III, therapeutic study.

Migration Patterns for Revision Total Knee Arthroplasty in the United States as Reported in the American Joint Replacement Registry.

BACKGROUND: Revision total knee arthroplasty (TKA) is associated with a higher complication rate and a greater cost when compared to primary TKA. Based on patient choice, referral, or patient transfers, revision TKAs are often performed in different institutions by different surgeons than the primary TKA. The aim of this study is to evaluate the effect of hospital size, teaching status, and revision indication on the migration patterns of failed primary TKA in patients 65 years of age and older. METHODS: All primary and revision TKAs reported to the American Joint Replacement Registry from January 2012 through March 2020 were included and merged with the Centers for Medicare and Medicaid Services database. Migration was defined as a patient having a primary TKA and revision TKA performed at separate institutions by different surgeons. RESULTS: In total, 9167 linked primary and revision TKAs were included in the analysis. Overall migration rates were significantly higher from small (<100 beds; P = .019), non-teaching institutions (P = .002) driven primarily by patients diagnosed with infection. Infection patients had significantly higher migration rates from small (46.8%, P < .001), non-teaching (43.5%, P < .001) institutions, while migration rates for other causes of revision were statistically similar. Most patients migrated to medium or large institutions (84.7%) for revision TKA rather than small institutions (15.3%, P < .001) and to teaching (78.3%) rather than non-teaching institutions (21.7%, P < .001). CONCLUSION: There is a diagnosis-dependent referral bias that affects the migration rates of infected primary TKA from small non-teaching institutions leading to a flow of more medically complex patients to medium and large teaching institutions for infected revision TKA.