Acute Periprosthetic Hip Fractures With Short, Uncemented Femoral Stems.

BACKGROUND: Uncemented femoral stems in hip arthroplasty have shown excellent long-term results, and several systematic studies indicate satisfactory performance of short stems. However, biomechanical and finite element analysis studies have suggested that shorter stems allow greater micromotion, producing greater strain at the implant-bone interface, which potentially increases the risk for periprosthetic fracture (PPF). We sought to assess this risk within our unit. METHODS: Our institution's arthroplasty database was searched for all primary total hip arthroplasties using short femoral stems performed between July 14, 2009 and August 29, 2022. The overall PPF rate and the PPF rate for individual femoral stems were established. Preoperative X-rays for each case were analyzed to characterize individual proximal femoral geometry. A data analysis was performed to identify risk factors for PPF. RESULTS: For the time period assessed, 3,192 short femoral stems were implanted. This included 1,561 of stem A and 1,631 of stem B. Women constituted 55.37% of the cohort. The average patient age was 66 years (range, 22 to 95). The PPF rate was 0.6%, with 19 PPFs identified at a follow-up of 3 months. There was a significantly higher fracture rate in stem A (0.96%) compared to stem B (0.25%) (P ≤ .01). Proximal femoral geometry, age, and sex were not determined to be risk factors for PPF in our cohort. Individual surgeons and surgical approaches appeared to confer no increased risk. There was no significant difference in average stem length, but multivariate analysis identified stem type and stem length as an independent risk factor for PPF. CONCLUSIONS: Our study identified individual stem and stem length as independent risk factors for PPF within our cohort. PPF is a multifactorial issue, and consensus on emerging risk factors such as implant design will hopefully inform decisions that can provide further risk reduction for individual patients.

Similar complication and readmission rates following simultaneous versus staged bilateral total hip arthroplasty.

PURPOSE: To compare short-term complications and readmission rates, in patients treated with simultaneous versus staged bilateral total hip arthroplasty (THA) within a year from the index procedure. METHODS: We reviewed the charts of patients that underwent simultaneous and staged-within a year-bilateral THA, between 2016 and 2020. Preoperative baseline characteristics were evaluated, while differences in terms of 30-day major and 30-day minor complications and readmission rates were compared between the groups. RESULTS: One-hundred-sixty patients (mean age, 64.3 years; SD, ± 11.7) were identified. Seventy-nine patients were treated with simultaneous (Group A) and eighty-one patients with staged (Group B) THA. There were no differences in baseline characteristic between the two groups (p > 0.050). Group A was more likely to receive general anesthesia (43% vs. 9.9%, p < 0.001) and had longer total operative time (182.8 vs. 128.0 min, p < 0.001). Group A had an overall shorter total length of hospital stay (5.8 vs. 8.6 days, p < 0.001). No differences in transfusion rates (p = 0.229) and no differences in major and minor complications (p > 0.05) were identified. Postoperative visits at the emergency department or readmissions were similar between the two groups (p > 0.050). CONCLUSION: This study shows that similar complication and readmission rates are expected after simultaneous and staged THA. Simultaneous bilateral THA is a safe and effective procedure, that should be considered for patients that present with radiologic and clinical bilateral hip disease.

Inter-segment coordination amplitude and variability during gait in patients with knee osteoarthritis and asymptomatic adults.

BACKGROUND: Inter-segment coordination examines the timing and coupling of multiple body segments and provides a complex understanding of how the neuromuscular system controls the body. Research is required to examine if inter-segment coordination during gait differs between individuals with different knee osteoarthritis (OA) severities and asymptomatic adults. RESEARCH QUESTION: Do inter-segment coordination amplitude and between-trial variability during gait differ between individuals with varying levels of knee OA severity and asymptomatic adults? METHODS: This observational, cross-sectional study included participants with mild/moderate knee OA (n = 38), severe knee OA (n = 24), and asymptomatic adults (n = 51). Participants ambulated overground at self-selected speeds. Data were collected with an eight-camera motion capture system and two force plates. Continuous relative phase (CRP) was used to quantify sagittal plane inter-segment coordination amplitude and between-trial variability for the thigh-shank and shank-foot pairs. Hierarchical linear models examined if CRP variables were related to the group (asymptomatic, mild/moderate OA, severe OA) after accounting for gait speed and gait phase. RESULTS: Thigh-shank CRP amplitude was significantly associated with group variables. The severe OA group had lower CRP amplitudes than both asymptomatic (b=8.57, 95 % confidence interval=2.75-14.38) and mild/moderate OA (b=5.69, 95 % confidence interval=-0.25 to 11.62) groups. Thigh-shank CRP variability was also associated with group. The severe OA group had lower CRP variability than the asymptomatic group (b=0.45, 95 % confidence interval=0.12-0.78); there were no differences between severe and mild/moderate OA groups (p > 0.050). There were no significant associations between any of the shank-foot CRP measures and the groups. SIGNIFICANCE: Lower thigh-shank CRP amplitude and variability in individuals with severe knee OA represents a more rigid motor system. These individuals could be attempting to stabilize their knee in response to a loss of passive stability or in response to pain. They might have difficulty adapting their gait to perturbations.

Indication for total knee arthroplasty based on preoperative functional score: Are we operating earlier?

BACKGROUND: The number of total knee arthroplasty (TKA) procedures performed annually is increasing for reasons not fully explained by population growth and increasing rates of obesity. The purpose of this study was to determine the role of patient functional status as an indication for surgery and to determine if patients are undergoing surgery with a higher level of preoperative function than in the past. METHODS: A systematic review and meta-analysis of the MEDLINE, Embase and Cochrane databases was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Functional status was assessed using the 36-Item Short Form Health Survey's physical component summary (PCS) score. Only primary procedures were included. Articles were screened by 2 independent reviewers, with conflicts resolved with a third reviewer. Meta-regression analysis was performed to determine the effect of time, age and sex on preoperative PCS score. Subgroup analysis was performed to compare results for the United States with those for the rest of the world. RESULTS: A total of 1502 articles were identified, of which 149 were included in the study. Data from 257 independent groups including 57 844 patients recruited from 1991 to 2015 were analyzed. The mean preoperative PCS score was 31.1 (95% confidence interval 30.6-31.7) with a 95% prediction interval of 22.8-39.5. The variance across studies was found to be significant (p < 0.001) with 99.01% true variance. Year of enrolment, age, the percentage of female patients and geographic region did not have any significant effect on preoperative PCS score. CONCLUSION: Patients are undergoing TKA with a level of preoperative function similar to their level of function in the past. Patient age, sex and location did not influence the functional status at which patients were considered to be candidates for surgery.

Outcomes of Ceramic-On-Ceramic Bearing Total Hip Arthroplasty: A Minimum 10-Year Follow-Up Study.

BACKGROUND: Although the fourth generation of ceramics has demonstrated excellent clinical results 5 to 6 years postoperatively, concerns over ceramic fracture and squeaking persist and longer-term follow-up (minimum 10 years) studies are warranted. Our study aimed to evaluate the minimum 10-year clinical outcomes and bearing-specific complications of ceramic-on-ceramic (CoC) total hip arthroplasties. METHODS: We retrospectively evaluated all patients who underwent primary delta CoC total hip arthroplasty in our institution between January 2004 and February 2013. Demographics, surgical techniques, complications, patient-reported outcomes, and radiographic outcomes were collected and analyzed. For continuous variables, the comparison between groups was conducted using a one-way analysis of variance. Of all 235 patients included in the study, 70.5% were women (190 hips). The mean follow-up period was 12 years (range, 10 to 18). The femoral head sizes of 28- mm, 32 mm, and 36 mm were used in 50, 26, and 197 cases, respectively. Mean acetabular inclination and anteversion angles were 39.2 ± 7.1° and 14.9 ± 3.5°. RESULTS: There were 5 hips revised at a mean 4.6 years (range, 0.1 to 7.1). One revision was squeaking-related. Squeaking was also reported by 8 other patients, but did not require revision. Other reasons for revision were early infection in 2 cases, stem loosening in 1 case, and stem fracture in 2 cases. The survival analysis for any causes for revision as an endpoint was 96.7% (95% confidence interval 0.313%-2.57%). CONCLUSION: We report excellent mean 12-year follow-up results regarding the complications and survivorship of the fourth generation CoC bearings.

Long-Term Survivorship of Cemented and Uncemented Polyethylene Liner Exchange.

BACKGROUND: Revision surgery is usually required for complications associated with total hip arthroplasty (THA). Significant morbidity can be associated with revision THA and thus some may only revise the liner of the original metal back component if it is found to be well fixed. We compare the long-term survivorship of cemented and uncemented head-liner THA exchange surgeries and possible causes. METHODS: Between 2000 and 2018, we reviewed cases from our arthroplasty database who underwent THA revision for head-liner exchange. We stratified our cohort into 2 groups: cemented and uncemented liners. Patients were followed clinically and radiographically to determine survivorship of the exchanges for both cemented and uncemented liners. Implant survivorship was measured using a competing risk analysis considering death and patients lost to follow-up as competing risks. RESULTS: A total of 84 patients (85 hips) underwent head-liner exchange surgery during the study period (21 cemented and 64 uncemented liners). The mean follow-up time was 6.9 years, with 75.3% and 24.7% of patients having been revised due to non-dislocation and dislocation causes, respectively. Two cemented liners (9.5%) and 11 uncemented liners (17.2%) required revision. The survival analysis of all head-liner revision was 86.4% at 18 years. Survival estimates liner exchanges due to dislocation versus non-dislocation groups were 57.3% versus 82.7% respectively (P = .034). CONCLUSION: The present study shows improved survivorship of head-liner exchanges performed due to non-dislocation etiology compared to dislocation etiology, but no difference in survivorship between cemented and uncemented head-liner exchange. LEVEL OF EVIDENCE: Level III.

Long-Term Outcome of Small Head Metal-On-Metal Total Hip Arthroplasty: A 15-to-22 Year Follow-Up.

BACKGROUND: The Metasul articular interface was a second-generation metal-on-metal (MoM) total hip arthroplasty (THA) that was introduced as a promising interface with improved manufacturing technology, better clearances, and enhanced metal hardness. In December 2001, the manufacturer recalled these implants due to the failure of cup osseointegration. METHODS: Between 1997 and 2004, 168 consecutive primary Metasul THAs were performed in 144 patients. Most patients received a cementless femoral and porous-coated acetabular component with 28 mm head. A competing risk analysis was performed for determination separately for bearing surface-related, recalled bearing failure, and end point revision for any reason. For clinical patient evaluation, we used Harris hip score and University of California at Los Angeles scores. Cobalt and chromium ion level measurement and standard radiographic assessment was performed. RESULTS: Of the 168 THAs, 19 hips were revised at a mean period of 15 years as follows: 12 of them were due to recalled acetabular component, five hips had noninterface-related complication, and two true interface surface failure. The survival distribution function of all hips with revision for any reason was 88.4%, for bearing interface relation 98.8%, and 92.6% for recalled cups. The mean Harris hip score and University of California at Los Angeles scores were 85 and 6, respectively, and the median Co and Cr blood levels were 1.0 and 0.91 µg/L. CONCLUSION: Excluding the recalled components, Metasul articular interface has performed extremely well at a minimum follow-up of 15 years in this relatively young population. There were two interface-related revisions in the entire cohort.

The Influence of Lateral and Posterior Total Hip Arthroplasty Approaches on Muscle Activation and Joint Mechanics During Gait.

BACKGROUND: Lateral and posterior total hip arthroplasty (THA) approaches disrupt muscle function, which could impact gait. The objectives of this study were to compare muscle activation and joint mechanics during gait, and isometric strength between participants after lateral and posterior THA approaches and healthy adults. METHODS: Participants 1 year post-THA from either lateral (n = 21) or posterior (n = 21) approaches, and healthy adults (n = 21) ambulated at self-selected speeds. Surface electromyography, optical motion capture, and force plates measured muscle activation and joint mechanics during gait. A dynamometer measured isometric torque. Gait characteristics and isometric torque were compared using analysis of variance and effect sizes (d). RESULTS: Lateral THA group had higher gluteus medius amplitudes during gait compared to the healthy group (P < .01, d = -0.97). Posterior THA group had higher gluteus maximus amplitudes during loading response (P = .02, d = -0.94) and higher hamstring amplitudes during midstance (P = .02, d = 0.45-1.31) than the healthy group. Both THA groups had decreased hip flexion and adduction angle excursions during gait (d = 0.89-1.14), but increased medial rotation angle excursions (d = -1.06 to -0.91), compared to the healthy group. Lateral THA group had lower isometric hip abduction torque than the healthy group (P = .03, d = 0.74). There was no pelvic drop in the THA groups. CONCLUSION: There were few differences in gait and isometric torque between lateral and posterior THA groups. The elevated muscle activation amplitudes in the lateral and posterior THA groups compared to healthy adults were likely due to muscle weakness. Despite these findings, there was no evidence of pelvic drop.

No Difference in Major Complication and Readmission Rates Following Simultaneous Bilateral vs Unilateral Total Hip Arthroplasty.

BACKGROUND: Simultaneous bilateral total hip arthroplasty (THA) is an attractive option for patients with osteoarthritis as it requires a single anesthetic and hospitalization. Nonetheless, serious concerns remain over the perioperative safety and rate of hospital readmission. The purpose of the present study was to compare the rate of 30-day major complications and hospital readmissions between patients undergoing simultaneous bilateral vs unilateral THA using the National Surgical Quality Improvement Program database. METHODS: The National Surgical Quality Improvement Program database was queried from 2011 to 2015 inclusively to identify all cases of elective, primary simultaneous bilateral THA and match them to a control group of unilateral THA cases. A multivariable regression analysis was then used to assess the relationship of simultaneous bilateral vs unilateral THA on major complications and readmissions. RESULTS: A total of 575 bilateral THA patients were matched to 2290 unilateral THA patients using a 4:1 ratio based on age, sex, and American Society of Anesthesiologists scores. Bilateral THA patients were more likely to undergo general anesthesia (77% vs 58.7%, P < .0001), required more postoperative transfusions (29.2% vs 15.9%, P < .0001) and were more often discharged to a rehabilitation facility rather than home (39.4% vs 20.8%, P < .0001). However, the adjusted odds of a major complication (odds ratio = 0.72, 95% confidence interval [0.41-1.24], P = .24) and 30-day readmission (odds ratio = 0.67, 95% confidence interval [0.38-1.19], P = .17) were similar between the 2 groups. CONCLUSION: Although patients who underwent simultaneous bilateral THA were more likely to be discharged to a rehabilitation facility and required significantly more perioperative transfusions compared to those undergoing unilateral THA, the odds of a 30-day major complication and readmission were similar between groups. LEVEL OF EVIDENCE: III.

Aspirin or Rivaroxaban for VTE Prophylaxis after Hip or Knee Arthroplasty.

BACKGROUND: Clinical trials and meta-analyses have suggested that aspirin may be effective for the prevention of venous thromboembolism (proximal deep-vein thrombosis or pulmonary embolism) after total hip or total knee arthroplasty, but comparisons with direct oral anticoagulants are lacking for prophylaxis beyond hospital discharge. METHODS: We performed a multicenter, double-blind, randomized, controlled trial involving patients who were undergoing total hip or knee arthroplasty. All the patients received once-daily oral rivaroxaban (10 mg) until postoperative day 5 and then were randomly assigned to continue rivaroxaban or switch to aspirin (81 mg daily) for an additional 9 days after total knee arthroplasty or for 30 days after total hip arthroplasty. Patients were followed for 90 days for symptomatic venous thromboembolism (the primary effectiveness outcome) and bleeding complications, including major or clinically relevant nonmajor bleeding (the primary safety outcome). RESULTS: A total of 3424 patients (1804 undergoing total hip arthroplasty and 1620 undergoing total knee arthroplasty) were enrolled in the trial. Venous thromboembolism occurred in 11 of 1707 patients (0.64%) in the aspirin group and in 12 of 1717 patients (0.70%) in the rivaroxaban group (difference, 0.06 percentage points; 95% confidence interval [CI], -0.55 to 0.66; P<0.001 for noninferiority and P=0.84 for superiority). Major bleeding complications occurred in 8 patients (0.47%) in the aspirin group and in 5 (0.29%) in the rivaroxaban group (difference, 0.18 percentage points; 95% CI, -0.65 to 0.29; P=0.42). Clinically important bleeding occurred in 22 patients (1.29%) in the aspirin group and in 17 (0.99%) in the rivaroxaban group (difference, 0.30 percentage points; 95% CI, -1.07 to 0.47; P=0.43). CONCLUSIONS: Among patients who received 5 days of rivaroxaban prophylaxis after total hip or total knee arthroplasty, extended prophylaxis with aspirin was not significantly different from rivaroxaban in the prevention of symptomatic venous thromboembolism. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT01720108 .).

Hospital Discharge within 2 Days Following Total Hip or Knee Arthroplasty Does Not Increase Major-Complication and Readmission Rates.

BACKGROUND: The rising costs of total knee arthroplasty (TKA) and total hip arthroplasty (THA) have resulted in a substantial economic burden on the U.S. health-care system. Recent efforts to contain these costs have targeted hospital length of stay. However, shorter hospital admissions have raised concerns over possible increases in complications and readmission rates. The purpose of this study was to assess whether early discharge, from 0 to 2 days postoperatively, was associated with increased 30-day major complications and readmissions compared with standard discharge, 3 to 4 days following THA or TKA. METHODS: The National Surgical Quality Improvement Program (NSQIP) database was queried to identify all patients who underwent an elective, primary unilateral THA or TKA between 2011 and 2012. For each procedure, 2 groups were created consisting of patients discharged from 0 to 2 days (early discharge) and those discharged from 3 to 4 days (standard discharge). Patient demographics and perioperative variables were compared between both discharge groups. Multivariable logistic-regression models were used to assess the independent effect of length of stay on 30-day major-complication and readmission rates. RESULTS: A total of 31,044 patients who underwent TKA and 19,909 patients who underwent THA were included. Overall, patients who were discharged early were younger and had fewer medical comorbidities and a lower American Society of Anesthesiologists (ASA) score. The multivariable logistic-regression model revealed that early discharge was not associated with increased odds of major complications following TKA (odds ratio [OR] = 0.95; 95% confidence interval [CI] = 0.75 to 1.20; p = 0.64). Furthermore, early discharge following THA was found to be an independent predictor against major complications (OR = 0.75; 95% CI = 0.58 to 0.95; p = 0.02). Lastly, early discharge was not an independent risk factor for hospital readmission following THA or TKA. CONCLUSIONS: Early discharge was not an independent risk factor for 30-day major complications or readmissions following THA or TKA. Rather, increased major complications and readmissions were attributed to patient comorbidities and perioperative variables. Early discharge within the first 2 days postoperatively for risk-stratified patients appears feasible without compromising patient care. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Navigated vs Conventional Total Knee Arthroplasty: Is There a Difference in the Rate of Respiratory Complications and Transfusions?

BACKGROUND: Proponents of navigation in total knee arthroplasty (TKA) report lower rates of systemic embolization and perioperative bleeding compared to conventional TKA given that breeching the intramedullary canal is not required. METHODS: We queried the National Surgical Quality Improvement Program to compare perioperative respiratory complications and transfusions between navigated and conventional TKA. We identified 2008 patients who underwent navigated TKA. These patients were matched 4:1 to a control group of 8026 patients. RESULTS: Conventional TKA resulted in similar odds of having a respiratory complication compared to navigated TKA (odds ratio = 1.35, P = .44). However, conventional TKA was found to be an independent predictor for requiring a transfusion perioperatively (odds ratio = 1.90, P < .001). CONCLUSION: Use of navigation in TKA results in less perioperative transfusions but has no influence on the rate of respiratory complications.

Major Complications and Transfusion Rates After Hemiarthroplasty and Total Hip Arthroplasty for Femoral Neck Fractures.

BACKGROUND: Postoperative complications and perioperative transfusions are common after hemiarthroplasty or total hip arthroplasty (THA) and can lead to increased morbidity and mortality. METHODS: The National Surgical Quality Improvement Program Database was queried to compare 30-day major complications and perioperative transfusions after femoral neck fractures. RESULTS: A total of 4058 patients were included in the study: 3192 were treated with hemiarthroplasty and 866 with THA. Multivariable logistic regression analysis revealed that having a THA was not an independent risk factor for major complications (odds ratio = 0.8, P = .18) but was an independent risk factor for requiring transfusions (odds ratio = 1.68, P < .001). CONCLUSION: The risk of major complications is influenced by patient factors rather than the choice of procedure. However, THA was a risk factor for transfusions after controlling for all other variables.

Deferoxamine Suppresses Collagen Cleavage and Protease, Cytokine, and COL10A1 Expression and Upregulates AMPK and Krebs Cycle Genes in Human Osteoarthritic Cartilage.

This study reports the effects of the iron chelator deferoxamine (DFO) on collagen cleavage, inflammation, and chondrocyte hypertrophy in relation to energy metabolism-related gene expression in osteoarthritic (OA) articular cartilage. Full-depth explants of human OA knee articular cartilage from arthroplasty were cultured with exogenous DFO (1-50 µM). Type II collagen cleavage and phospho-adenosine monophosphate-activated protein kinase (pAMPK) concentrations were measured using ELISAs. Gene expression studies employed real-time PCR and included AMPK analyses in PBMCs. In OA explants collagen cleavage was frequently downregulated by 10-50 µM DFO. PCR analysis of 7 OA patient cartilages revealed that 10 µM DFO suppressed expression of MMP-1, MMP-13, IL-1ß, and TNFα and a marker of chondrocyte hypertrophy, COL10A1. No changes were observed in the expression of glycolysis-related genes. In contrast, expressions of genes associated with the mitochondrial Krebs cycle (TCA), AMPK, HIF1α, and COL2A1 were upregulated. AMPK gene expression was reduced in OA cartilage and increased in PBMCs from the same patients compared to healthy controls. Our studies demonstrate that DFO is capable of suppressing excessive collagenase-mediated type II collagen cleavage in OA cartilage and reversing phenotypic changes. The concomitant upregulation of proanabolic TCA-related gene expressions points to a potential for availability of energy generating substrates required for matrix repair by end-stage OA chondrocytes. This might normally be prevented by high whole-body energy requirements indicated by elevated AMPK expression in PBMCs of OA patients.

Shorter Hospital Stay and Lower 30-Day Readmission After Unicondylar Knee Arthroplasty Compared to Total Knee Arthroplasty.

BACKGROUND: Reducing hospital stay and unplanned hospital readmission of arthroplasty patients has been a topic of recent interest. The aim of the present study was to query the National Surgical Quality Improvement Program database to compare the length of hospital stay (LOS) and the subsequent 30-day hospital readmission rates in patients undergoing primary unicondylar knee arthroplasty (UKA) and total knee arthroplasty (TKA). METHODS: We identified 1340 UKAs and 36,274 TKAs over a 2-year period (2011-2012). Patient demographics, comorbidities, LOS, 30-day postoperative complications, and readmission rates were compared between the groups. Multivariate regression analysis was used to determine the effect of procedure type on LOS and readmission rates. RESULTS: Unicondylar knee arthroplasty patients had a median LOS of 2 days compared to 3 days for TKAs (P < .001). The readmission rate in the TKA group was nearly double that of the UKA group (4.1% vs 2.2%) (P < .0001). Multivariate regression analysis identified that undergoing a UKA was predictive for a shorter LOS (coefficient -1 day) and was protective for 30-day readmission (odds ratio, 0.60; 95% confidence interval, 0.41-0.88). CONCLUSION: Patients undergoing UKA had a shorter LOS and a lower 30-day readmission rate compared to TKA patients. After adjusting for selected cofounders, we demonstrated that undergoing a UKA is a protective factor for 30-day readmission.

Simultaneous Bilateral Versus Unilateral Total Knee Arthroplasty: A Comparison of 30-Day Readmission Rates and Major Complications.

We queried the National Surgical Quality Improvement Program to compare the rate of 30-day readmissions and major complications between simultaneous bilateral and unilateral total knee arthroplasty (TKA). We identified 1771 patients who underwent simultaneous (same-day) bilateral TKA and matched them to a control group of 6790 patients who underwent unilateral TKA. The simultaneous bilateral TKA patients had longer surgery, were more commonly performed under general anesthesia, had a higher rate of postoperative transfusion, and a greater proportion of patients discharged to rehabilitation facilities. Simultaneous bilateral TKA has a low incidence of major complications and was not associated with more readmissions as compared to unilateral TKA (3.6% versus 3.5% respectively). Nonetheless, the odds of major complications was slightly higher following simultaneous bilateral TKA (OR=1.58).

Favorable Results of a Short, Tapered, Highly Porous, Proximally Coated Cementless Femoral Stem at a Minimum 4-Year Follow-Up.

BACKGROUND: Shorter femoral stems have been increasingly used in total hip arthroplasty. However, there are few clinical studies evaluating the outcomes of these stems and comparing them to their regular-sized counterparts. METHODS: Our study provides radiologic and functional outcomes at 5-year mean follow-up of 131 cementless Tri-Lock Bone Preservation Stems, a short tapered stem with a proximal porous coating. RESULTS: Stem-related complications were low with one revision for stem aseptic loosening. Kaplan-Meier analysis estimated 99.2% stem survival rate at 5 years, comparable to conventional length Tri-Lock stems (99.8% at 8.9 years). CONCLUSION: This study demonstrates that the Tri-Lock Bone Preservation Stem can provide successful outcomes at 5-year follow-up. Further studies are required to determine the long-term outcome of these implants in patients with poor bone stock.

Comparison of US and Canadian Perioperative Outcomes and Hospital Efficiency After Total Hip and Knee Arthroplasty.

IMPORTANCE: The combination of an aging population, growing number of medical interventions, and surging economic burden of health care has renewed interest in reevaluating and exploring new health care models. OBJECTIVES: To compare the performance of the US and Canadian health care systems by assessing major complications following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) and to measure the efficiency of both health care models by comparing the postoperative length of stay. DESIGN, SETTING, AND PARTICIPANTS: With patients grouped according to the country where they underwent surgery, we queried the National Surgical Quality Improvement Program database to identify 55,335 Canadian and US patients who underwent primary elective THA or TKA between January 1, 2011, and December 31, 2012. MAIN OUTCOMES AND MEASURES: Differences in patient demographics, as well as the rate of 30-day major complications and length of stay, were compared between patients hospitalized in the United States and Canada. RESULTS: Baseline characteristics were similar between the groups. Most US patients underwent general anesthesia (THA, 61.8%; TKA, 59.4%); Canadian patients received more regional anesthesia (THA, 78.7%; TKA, 81.0%). Patients in the United States received more transfusions postoperatively (THA, 9.0% more; TKA, 6.4% more; P < .001) and had shorter hospitalizations (THA, 1.4 days less; TKA, 1.3 days less; P < .001) with a greater proportion of patients discharged to rehabilitation facilities (THA, 21.6% more; TKA, 26.6% more; P < .001). With results reported as incidence rate ratios (95% CIs), after adjusting for all other variables, risk factors, and adverse outcomes, having surgery in Canada increased the postoperative length of stay by 57% (1.57 [1.53-1.61]) for THA and 49% (1.49 [1.46-1.52]) for TKA. With results reported as odds ratios (95% CIs), major complications were significantly more common in Canada following TKA (1.65 [1.31-2.07]) but not THA (1.09 [0.79-1.51]). CONCLUSIONS AND RELEVANCE: The rate of major complications was significantly higher in Canada following TKA, but there was no significant difference following THA. Patients undergoing the procedures in US hospitals also had substantially shorter lengths of hospital stay, perhaps reflecting more efficient postoperative care and discharge planning in those facilities.