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Elevated ESR and CRP Prior to Second-Stage Reimplantation Knee Revision Surgery for Periprosthetic Joint Infection Are Associated with Increased Reinfection Rates

Although two-stage revision surgery is considered as the most effective treatment for managing chronic periprosthetic joint infection (PJI), there is no current consensus on the predictors of optimal timing to second-stage reimplantation. This study aimed to compare clinical outcomes between patients with elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) prior to second-stage reimplantation and those with normalized ESR and CRP prior to second-stage reimplantation. We retrospectively reviewed 198 patients treated with two-stage revision total knee arthroplasty for chronic PJI. Cohorts included patients with: (1) normal level of serum ESR and CRP (n = 96) and (2) elevated level of serum ESR and CRP prior to second-stage reimplantation (n = 102). Outcomes including reinfection rates and readmission rates were compared between both cohorts. At a mean follow-up of 4.4 years (2.8-6.5 years), the elevated ESR and CRP cohort demonstrated significantly higher reinfection rates compared with patients with normalized ESR and CRP prior to second-stage reimplantation (33.3% vs. 14.5%, p < 0.01). Patients with both elevated ESR and CRP demonstrated significantly higher reinfection rates, when compared with patients with elevated ESR and normalized CRP (33.3% vs. 27.6%, p = 0.02) as well as normalized ESR and elevated CRP (33.3% vs. 26.3%, p < 0.01). This study demonstrates that elevated serum ESR and/or CRP levels prior to reimplantation in two-stage knee revision surgery for chronic PJI are associated with increased reinfection rate after surgery. Elevation of both ESR and CRP were associated with a higher risk of reinfection compared with elevation of either ESR or CRP, suggesting the potential benefits of normalizing ESR and CRP prior to reimplantation in treatment of chronic PJI.

The Effect of Joint Line Elevation on In Vivo Knee Kinematics in Bicruciate Retaining Total Knee Arthroplasty

Prior studies have reported a negative effect on both clinical outcomes and patient-reported outcome measures (PROMS) following joint line elevation (JLE) in cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior stabilized (PS) TKA designs. This experimental study was aimed to quantify the effect of JLE on in vivo knee kinematics in patients with bicruciate retaining (BCR) TKA during strenuous activities. Thirty unilateral BCR TKA patients were evaluated during single-leg deep lunge and sit-to-stand using a validated combined computer tomography and dual fluoroscopic imaging system. Correlation analysis was performed to quantify any correlations between JLE and in vivo kinematics, as well as PROMS. There was a significant negative correlation between JLE and maximum flexion angle during single-leg deep lunge (ρ = -0.34, p = 0.02), maximum varus joint angles during single-leg deep lunge (ρ = -0.37, p = 0.04), and sit-to-stand (ρ = -0.29, p = 0.05). There was a significant negative correlation between JLE and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (ρ = -0.39, p = 0.01) and knee disability and osteoarthritis outcome score physical function (KOOS-PS; ρ = -0.33, p = 0.03). The JLE that yields a significant loss in PROMS and maximum flexion angles were 2.6 and 2.3 mm, respectively. There was a linear negative correlation of JLE with both in vivo knee kinematics and PROMS, with changes in JLE of greater than 2.6 and 2.3 mm, leading to a clinically significant loss in PROMS and maximum flexion angles, respectively, suggesting an increased need to improve surgical precision to optimize patient outcomes following BCR TKA.

Knee Arthroscopy Prior to Revision TKA Is Associated with Increased Re-Revision for Stiffness

This is an experimental study. As knee arthroscopy may be used as a suitable temporizing alternative prior to revision surgery, knee arthroscopy potentially may be a risk factor for subsequent adverse outcomes after revision total knee arthroplasty (TKA). This study aimed to evaluate the impact of prior knee arthroscopy on outcomes of subsequent TKA revision surgery. We identified 1,689 consecutive patients who underwent revision TKA: (1) patients with no prior knee arthroscopy (n = 1,549) and (2) patients with knee arthroscopy prior to revision TKA (n = 140). A control group of matched revision TKA patients who did not undergo prior knee arthroscopy was identified (700 patients), using one-to-five matching. Matched patients with prior knee arthroscopy demonstrated an increased likelihood of requiring re-revision (odds ratio [OR], 2.06, p < 0.001), particularly for stiffness (OR, 2.72, p < 0.02) compared with patients who underwent revision TKA without prior knee arthroscopy. Knee arthroscopy demonstrated a time-dependent impact on revision TKA outcomes, with an increased likelihood of requiring re-revision for patients who underwent knee arthroscopy within 6 months prior to revision TKA compared with patients who underwent knee arthroscopy within 6 to 12 months prior to revision TKA (OR, 3.16, p < 0.04). This cohort matched study shows that patients who had prior knee arthroscopy demonstrated a significantly higher likelihood of requiring re-revision compared with patients who underwent revision TKA without prior knee arthroscopy. Additionally, there was a significant increased likelihood in requiring re-revision for patients who had prior knee arthroscopy within 6 months. This provides clinically useful information for counseling of patients who are considering temporizing their symptoms with knee arthroscopy prior to revision TKA.

Gait and Knee Flexion In Vivo Kinematics of Asymmetric Tibial Polyethylene Geometry Cruciate Retaining Total Knee Arthroplasty

The preservation of the posterior cruciate ligament in cruciate retaining (CR) total knee arthroplasty (TKA) designs has the potential to restore healthy knee biomechanics; however, concerns related to kinematic asymmetries during functional activities still exist in unilateral TKA patients. As there is a limited data available regarding the ability of the contemporary CR TKA design with concave medial and convex lateral tibial polyethylene bearing components to restore healthy knee biomechanics, this study aimed to investigate in vivo three-dimensional knee kinematics in CR TKA patients during strenuous knee flexion activities and gait. Using a combined computer tomography and dual fluoroscopic imaging system approach, in vivo kinematics of 15 unilateral CR TKA patients (comparison of replaced and contralateral nonreplaced knee) were evaluated during sit-to-stand, step-ups, single-leg deep lunge, and level walking. The patient cohort was followed-up at an average of 24.5 months ( ± 12.6, range 13-42) from surgical procedure. Significantly smaller internal knee rotation angles were observed for the contemporary CR TKA design during step-ups (2.6 ± 5.8 vs. 6.3 ± 6.6 degrees, p < 0.05) and gait (0.6 ± 4.6 vs. 6.3 ± 6.8 degrees, p < 0.05). Significantly larger proximal and anterior femoral translations were measured during sit-to-stand (34.7 ± 4.5 vs. 29.9 ± 3.1 mm, p < 0.05; -2.5 ± 2.9 vs. -8.1 ± 4.4 mm, p < 0.05) and step-ups (34.1 ± 4.5 vs. 30.8 ± 2.9 mm, p < 0.05; 2.2 ± 3.2 vs. -3.5 ± 4.5 mm, p < 0.05). Significantly smaller ranges of varus/valgus and internal/external rotation range of motion were observed for CR TKA, when compared with the nonoperated nee, during strenuous activities and gait. The preservation of the posterior cruciate ligament in the contemporary asymmetric bearing geometry CR TKA design with concave medial and convex lateral tibial polyethylene bearing components has the potential to restore healthy knee biomechanics; however, the study findings demonstrate that native knee kinematics were not fully restored in patients with unilateral asymmetric tibial polyethylene bearing geometry CR TKA during functional activities.

Outcomes of Tourniquet-Less Revision Total Knee Arthroplasty: A Matched Cohort Analysis

INTRODUCTION

A tourniquet is routinely used in total knee arthroplasty (TKA) to limit perioperative blood loss and increase the visibility of the surgeon's field of view. This study aims to evaluate the postoperative clinical outcomes and complications associated with tourniquet use in revision TKA.

METHODS

We conducted a retrospective review of 1,904 consecutive patients who underwent revision TKA. Propensity score-based matching was done to adjust for baseline differences in patient demographics and procedure details.

RESULTS

Propensity score matching resulted in a cohort of 548 revision total joint arthroplasty patients, 274 (50.0%) of whom were tourniquet patients matched to 274 (50.0%) tourniquet-less patients. Multivariate regression analyses demonstrated that, compared with the tourniquet-less cohort, the tourniquet cohort had significantly less intraoperative (413.7 to 353.2 mL, P < 0.01) and total perioperative (1,548.7 to 1,417.8 mL, P < 0.01) blood loss. However, no significant differences were present in total perioperative (8.4%, 6.6%, P = 0.43) transfusion rates. The tourniquet cohort had increased length of stay (3.2 to 3.7 days, P < 0.001) and 30-day readmissions (P = 0.04).

DISCUSSION

This study demonstrated that although omitting the tourniquet in revision TKA leads to markedly increased perioperative blood loss, notable differences in perioperative transfusion rates were not observed. Furthermore, revision TKA without tourniquet use was associated with reduced postoperative length of stay, 30-day readmissions, and increased range of flexion.

Lumbar Spine Fusion Before Revision Total Hip Arthroplasty Is Associated With Increased Dislocation Rates

BACKGROUND

The aim of this study was to determine whether timing of lumbar spinal fusion (LSF) before revision total hip arthroplasty (THA) would impact dislocation and rerevision rates.

METHODS

This retrospective analysis includes a total of 505 patients who underwent revision THA with concomitant diagnosis of degenerative lumbar spinal stenosis with spondylolisthesis. Patients were stratified into the following two cohorts: (1) 328 patients who underwent revision THA with previous LSF and (2) 177 patients who underwent revision THA, followed by LSF. Postoperative complications including dislocation and rerevision rates were evaluated.

RESULTS

Patients who underwent revision THA with previous LSF demonstrated significantly higher dislocation rates and rerevision rates compared with patients who underwent revision THA, followed by LSF, at the 1-year follow-up (6.7% versus 5.1%, P < 0.01; 8.5% versus 7.0%, P = 0.02). Patients who underwent revision THA, followed by LSF within 1 year demonstrated significantly higher dislocation and rerevision rates (5.6% versus 4.1%; 7.6% versus 6.4%).

DISCUSSION

This study demonstrates that patients who underwent revision THA with previous LSF demonstrated notably higher dislocation rates and rerevision rates compared with patients who underwent revision THA, followed by LSF, with the greater the intervals between revision THA and LSF, the lower the postoperative dislocation rates and rerevision rates.

Impact of Smoking and Drinking on Complications After Revision Total Joint Arthroplasty: A Matched Cohort Analysis

INTRODUCTION

Smoking and drinking have been shown to impair postoperative outcomes in primary hip and knee total joint arthroplasty (TJA). This study aimed to evaluate the potential impact of smoking and drinking on complications after revision TJA.

METHODS

We retrospectively evaluated a total of 4,302 consecutive patients who underwent revision TJA. Patient demographics and complications were compared between four cohorts based on smoking and drinking status: (1) nonusers (nonsmokers and nondrinkers), (2) smokers, (3) drinkers, and (4) concurrent users.

RESULTS

A total of 1,924 patients were matched using propensity score analysis: 808 nonusers (42.0%), 421 smokers (21.9%), 483 drinkers (25.0%), and 212 concurrent users (11.1%). When compared with nonusers, smokers, drinkers, and concurrent users (simultaneous smokers and drinkers) exhibited higher odds for both inhospital complications (odds ratios, smokers: 2.40, drinkers: 1.55, and concurrent users: 5.13, P < 0.01). Among the user cohorts, although smokers and drinkers showed similar rates of 90-day postdischarge complications (smokers: 14.95% and drinkers: 14.80%, P = 0.95), concurrent users demonstrated the highest significant odds for these complications (odds ratio, 1.64, P = 0.02).

DISCUSSION

Our propensity-score-matched cohort study results demonstrate that although the smokers and drinkers groups shared similarly poor outcomes after discharge, concurrent users were found to have the worst outcomes compared with either single user group.

Outcome of Spinal Versus General Anesthesia in Revision Total Hip Arthroplasty: A Propensity Score-Matched Cohort Analysis

INTRODUCTION

Spinal anesthesia has been previously shown to offer improved patient outcomes compared with general anesthesia in revision total knee arthroplasty. This study aimed to evaluate the potential differences in perioperartive and postoperative outcomes in revision total hip arthroplasty (THA) between spinal or general anesthesia.

METHODS

A total of 2,656 consecutive patients who underwent revision THA were evaluated. Propensity-score-adjusted multivariate logistic regression analyses were applied to control for intergroup variability and evaluate the differences in outcomes and complications with anesthesia type.

RESULTS

Propensity score matching resulted in 1:1 matching with 265 patients in each anesthesia cohort. Multivariate analyses demonstrated that patients administered general anesthesia had a significantly longer procedure time (174.8 versus 161.3, P < 0.01), higher intraoperative (402.6 versus 305.5 mL, P < 0.01), and total perioperative blood loss (1802.2 versus 1,684.2 mL,P < 0.01). In addition, patients administered general anesthesia were found to have higher odds for two or more inhospital complications (odds ratio, 4.51, P < 0.01) and extended length of stay (odds ratio, 2.45, P = 0.02).

DISCUSSION

Our study shows that propensity-matched patients who received spinal anesthesia for revision THA exhibited notable reduction in surgical time, perioperative blood loss, and complications compared with patients who received general anesthesia, suggesting that spinal anesthesia is a viable alternative to general anesthesia in revision THA.

Three-dimensional kinematic analysis of dislocation mechanism in dual mobility total hip arthroplasty constructs

Dual mobility (DM) total hip arthroplasty (THA) is associated with reduced dislocation rates; however, the kinematic mechanism of dislocation in DM THA constructs is still not well understood. This study hypothesizes that the difference in kinematics between DM THA and conventional THA designs contributes to reduced dislocation rates of DM THA. In addition, this study aims to quantify and compare those kinematic parameters between DM THA and conventional THA using a validated dual fluoroscopy imaging system (DFIS) and finite element (FE) modelling. Fresh frozen cadavers were measured to compare the impingement-free range of motion and provocative subluxation kinematics among three THA constructs: (1) DM, (2) constrained liner (CS), and (3) 36 mm head diameter neutral liner (NL). The DFIS was used to measure the in vitro kinematics of the hip. Subject-specific FE models were developed to assess the horizontal dislocation distance and resistive torque at dislocation. The DM construct head exhibited increased provocative anterior and posterior subluxation range of motion before dislocation when compared to CS constructs (p = .05; p = .03), as well as NL constructs (p = .05). The DM THA showed a significantly larger posterior horizontal dislocation distance, as well as smaller resistive torque at dislocation, when compared to NL (p = .05; p = .03) and CS constructs (p = .04; p = .01). Our findings demonstrate there was increased provocative subluxation range of motion as well as normalized jump distance for the DM constructs compared to the NL and CS constructs, suggesting the DM THA may provide increased stability hip during at-risk functional hip positions.

Minority Race and Ethnicity is Associated With Higher Complication Rates After Revision Surgery for Failed Total Hip and Knee Joint Arthroplasty

BACKGROUND

Racial and ethnic disparities in access to hip and knee total joint arthroplasty (TJA) and postoperative outcomes have wide-reaching implications for patients and the health care system. The aim of this study is to evaluate the effect of ethnicity on clinical outcomes and complications following revision hip and knee TJA.

METHODS

A single-institution, retrospective analysis of a consecutive series of 4424 revision hip and knee TJA patients was evaluated. Student's t-test and chi-squared analysis were used to identify significant differences in patient demographics and clinical outcomes between Caucasians and various ethnic minorities, including African Americans, Hispanics, and Asians.

RESULTS

When compared with white patients, African American patients demonstrated a significantly higher BMI (P = .04), ASA score (P = .04), length of hospital stay (P = .06), and postoperative infection rates (P = .04). Hispanics demonstrated a significantly higher BMI (P = .04), when compared with white patients, alongside a significantly higher risk for postoperative infection (P < .01). African American demonstrated a significantly higher ASA score (P = .02; P = .03), when compared with Hispanics and Asians, alongside a significantly increased length of stay (P = .01) and higher risk for postoperative infection (P = .02).

CONCLUSION

The study findings demonstrate an underutilization of revision TJA by ethnic minority groups, suggesting that disparities in access to orthopedic surgery increase from primary to revision surgery despite higher failure rates of minority ethnic groups reported after primary TJA surgery. In addition, inferior postoperative outcomes were associated with African Americans and Hispanics, when compared to white patients, with African Americans demonstrating the highest risk of postoperative complications.

Outcomes and Risk Factors Associated With 2-Stage Reimplantation Requiring an Interim Spacer Exchange for Periprosthetic Joint Infection

BACKGROUND

Patients undergoing a 2-stage revision for periprosthetic joint infection (PJI) often require a repeat spacer in the interim due to persistent infection. This study aims to report outcomes for patients with repeat spacer exchange and to identify risk factors associated with interim spacer exchange in 2-stage revision arthroplasty.

METHODS

A total of 256 consecutive 2-stage revisions for chronic infection of total hip arthroplasty and total knee arthroplasty with reimplantation and minimum 2-year follow-up were investigated. An interim spacer exchange was performed in 49 patients (exchange cohort), and these patients were propensity score matched to 196 patients (nonexchange cohort). Multivariate analysis was performed to analyze risk factors for failure of interim spacer exchange.

RESULTS

Patients in the propensity score-matched exchange cohort demonstrated a significantly increased reinfection risk compared to patients without interim spacer exchange (24% vs 15%, P = .03). Patients in the propensity score-matched exchange cohort showed significantly lower postoperative scores for 3 patient-reported outcome measures (PROMs): hip disability and osteoarthritis outcome score physical function (46.0 vs 54.9, P = .01); knee disability and osteoarthritis outcome score physical function (43.1 vs 51.7, P < .01); and patient-reported outcomes measurement information system physical function short form (41.6 vs 47.0, P = .03). Multivariate analysis demonstrated Charles Comorbidity Index (odds ratio, 1.56; P = .01) and the presence of Enterococcus species (odds ratio, 1.43; P = .03) as independent risk factors associated with 2-stage reimplantation requiring an interim spacer exchange for periprosthetic joint infection.

CONCLUSION

This study demonstrates that patients with spacer exchange had a significantly higher risk of reinfection at 2 years of follow-up. Additionally, patients with spacer exchange demonstrated lower postoperative PROM scores and diminished improvement in multiple PROM scores after reimplantation, indicating that an interim spacer exchange in 2-stage revision is associated with worse patient outcomes.

Outcome of Debridement, Antibiotics, and Implant Retention With Modular Component Exchange in Acute Culture-Negative Periprosthetic Joint Infections

BACKGROUND

Modular component exchange and culture-directed antibiotic treatment is routinely employed for acute periprosthetic joint infection (PJI). However, as many as 7%-23% of PJIs have been reported to yield negative culture results. The efficacy of debridement, antibiotics, and implant retention (DAIR) with modular component exchange in the setting of acute culture negative PJI remains largely unknown. The aim of our study is to evaluate the outcomes of DAIR with modular component exchange in acute culture-positive and culture-negative PJI.

METHODS

A total of 149 consecutive patients with primary total joint replacements (90 total knee arthroplasties and 59 total hip arthroplasties) who underwent DAIR with modular component exchange for acute PJI with at least 3 years of follow-up were evaluated: (1) 46 culture-negative PJI patients and (2) 103 culture-positive PJI patients. Reinfection and aseptic revision rates along with complication rates were compared.

RESULTS

The reinfection rate for DAIR in acute culture-negative PJI was 13.0% compared to 19.4% in culture-positive PJI (P = .48). Mean survival time from reinfection between culture-negative (7.7 ± 0.4 years) and culture-positive (7.4 ± 0.3 years) PJI groups did not differ significantly (P = .40). Aseptic revision rates were 8.7% and 4.9% (P = .46), respectively, with loosening being the primary reason for implant failure in both cohorts.

CONCLUSIONS

Despite lack of an identifying organism to guide postoperative antibiotic therapy, DAIR with modular component exchange for acute culture-negative PJI was associated with similar reinfection rates compared to acute culture-positive PJI, suggesting that culture negativity may not be a contraindication to DAIR in patients with acute PJI.