Traditional Laboratory Markers Hold Low Diagnostic Utility for Immunosuppressed Patients With Periprosthetic Joint Infections.

BACKGROUND: Although predictive laboratory markers and cutoffs for immunocompetent patients are well-studied, similar reference ranges and decision thresholds for immunosuppressed patients are less understood. We investigated the utility of typical laboratory markers in immunosuppressed patients undergoing aspiration of a prosthetic hip or knee joint. METHODS: A retrospective review of adult patients with an immunosuppressed state that underwent primary and revision total joint arthroplasty with a subsequent infection at our tertiary, academic institution was conducted. Infection was defined by Musculoskeletal Infection Society criteria. A multivariable analysis was used to identify independent factors associated with acute (<90 days) and chronic (>90 days) infection. Area under the receiver-operator curve (AUC) was used to determine the best supported laboratory cut points for identifying infection. RESULTS: We identified 90 patients with immunosuppression states totaling 172 aspirations. Mean follow-up from aspiration was 33 months. In a multivariate analysis, only synovial fluid cell count and synovial percent neutrophils were found to be independently correlated with both acute and chronic infection. A synovial fluid cell count cutoff value of 5679 nucleated cells/mm3 maximized the AUC (0.839) for predicting acute infection, while a synovial fluid cell count cutoff value of 1293 nucleated cells/mm3 maximized the AUC (0.931) for predicting chronic infection. CONCLUSION: Physicians should be aware of lower levels of synovial nucleated cell count and percentage of neutrophils in prosthetic joint infections of the hip or knee in patients with immunosuppression. Further investigation is necessary to identify the best means of diagnosing periprosthetic joint infection in this patient population.

Prior Hip Arthroscopy Increases Risk for Perioperative Total Hip Arthroplasty Complications: A Matched-Controlled Study.

BACKGROUND: Arthroscopic hip surgery is becoming increasingly popular for the treatment of femoroacetabular impingement and labral tears. Reports of outcomes of hip arthroscopy converted to total hip arthroplasty (THA) have been limited by small sample sizes. The purpose of this study was to investigate the impact of prior hip arthroscopy on THA complications. METHODS: We queried our institutional database from January 2005 and December 2017 and identified 95 hip arthroscopy conversion THAs. A control cohort of 95 primary THA patients was matched by age, gender, and American Society of Anesthesiologists score. Patients were excluded if they had undergone open surgery on the ipsilateral hip. Intraoperative complications, estimated blood loss, operative time, postoperative complications, and need for revision were analyzed. Two separate analyses were performed. The first being intraoperative and immediate postoperative complications through 90-day follow-up and a second separate subanalysis of long-term outcomes on patients with minimum 2-year follow-up. RESULTS: Average time from hip arthroscopy to THA was 29 months (range 2-153). Compared with primary THA controls, conversion patients had longer OR times (122 vs 103 minutes, P = .003). Conversion patients had a higher risk of any intraoperative complication (P = .043) and any postoperative complication (P = .007), with a higher rate of wound complications seen in conversion patients. There was not an increased risk of transfusion (P = .360), infection (P = 1.000), or periprosthetic fracture between groups (P = .150). When comparing THA approaches independent of primary or conversion surgery, there was no difference in intraoperative or postoperative complications (P = .500 and P = .790, respectively). CONCLUSION: Conversion of prior hip arthroscopy to THA, compared with primary THA, resulted in increased surgical times and increased intraoperative and postoperative complications. Patients should be counseled about the potential increased risks associated with conversion THA after prior hip arthroscopy.

Treatment of Prosthetic Joint Infection: Established Patient Relationships May Impact Medical Decision-Making.

BACKGROUND: Choosing the intervention for prosthetic joint infections, whether debridement, antibiotics, and implant retention (DAIR), or explant and antibiotic spacer placement, is multifactorial. One characteristic that may influence this decision is a previously established relationship with the patient. We hypothesized that patients receiving their arthroplasty at an outside institution and presenting with infection would be more likely to undergo removal of their implant without an attempt at DAIR compared to patients who underwent primary arthroplasty at the investigating institution. METHODS: The institutional database was queried for primary total hip and knee arthroplasty infections. Manual review of medical records was performed, excluding patients who did not meet the Musculoskeletal Infection Society definition of infection. Patient demographics, medical comorbidities, presenting infection characteristics, and surgical intervention were collected. Multivariable analysis was performed to determine the independent predictors of treatment. RESULTS: A total of 270 patients were included for analysis. McPherson score (P < .001) and duration of symptoms (P < .001) were associated with subsequent treatment. Additionally, when controlling for age, gender, symptom duration category, procedure, McPherson score, and American Society of Anesthesiologists category, patients with index procedures at outside hospitals were more likely to undergo implant removal (odds ratio, 36.30; 95% confidence interval, 8.16-161.51; P < .001). CONCLUSION: Patients receiving their primary arthroplasty at an outside hospital and presenting with infection are more likely to undergo removal of hardware as their initial treatment. To avoid treatment bias, institutional protocols should be implemented to guide the shared decision-making process.

Predicting Inpatient Dissatisfaction Following Total Joint Arthroplasty: An Analysis of 3,593 Hospital Consumer Assessment of Healthcare Providers and Systems Survey Responses.

BACKGROUND: The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey, created by the Centers for Medicare and Medicaid, is directly tied to hospital reimbursement. The purpose of this study is to identify factors that are predictive HCAHPS survey responses following primary hip and knee arthroplasty. METHODS: Prospectively collected HCAHPS responses from patients undergoing elective hip and knee arthroplasty between January 2013 and October 2017 at our institution were analyzed. Patient age, gender, race, marital status, body mass index, American Society of Anesthesiologists score, preoperative pain score, smoking status, alcohol use, illegal drug use, socioeconomic quartile, insurance type, procedure type, hospital type (academic vs community), distance to medical center, length of stay (LOS), and discharge disposition were obtained and correlated with HCAHPS inpatient satisfaction scores. RESULTS: Responses from 3593 patients were obtained: 1546 total hip arthroplasties, 1899 total knee arthroplasties, and 148 unicompartmental knee arthroplasties. Mean overall HCAHPS score was 79.2. Women had lower inpatient satisfaction than men (77.6 vs 81.6, P < .001). Alcohol consumers had lower inpatient satisfaction than abstainers (77.7 vs 81.6, P < .001). Inpatient satisfaction varied by socioeconomic quartile (P < .001) with patients in the highest quartile having lower satisfaction than patients in all other quartiles (P < .001). Patients discharged to a facility had lower inpatient satisfaction than those discharged home (71.2 vs 80.2, P < .001). An inverse correlation between inpatient satisfaction and LOS (r = -0.19, P < .001) and a direct correlation between satisfaction and distance to medical center (r = 0.06, P < .001) were seen. CONCLUSION: Patients more likely to report lower levels of inpatient satisfaction after total joint arthroplasty are female, affluent, and alcohol consumers, who are discharged to postacute care facilities. Inpatient satisfaction was inversely correlated with LOS and positively correlated with distance from patient home to medical center. These findings provide targets for improvements in TJA inpatient care.

Patient expectation is the most important predictor of discharge destination after primary total joint arthroplasty.

The purpose of this study was to identify preoperative predictors of discharge destination after total joint arthroplasty. A retrospective study of three hundred and seventy-two consecutive patients who underwent primary total hip and knee arthroplasty was performed. The mean length of stay was 2.9 days and 29.0% of patients were discharged to extended care facilities. Age, caregiver support at home, and patient expectation of discharge destination were the only significant multivariable predictors regardless of the type of surgery (total knee versus total hip arthroplasty). Among those variables, patient expectation was the most important predictor (P < 0.001; OR 169.53). The study was adequately powered to analyze the variables in the multivariable logistic regression model, which had a high concordance index of 0.969.

Preoperative predictors of extended hospital length of stay following total knee arthroplasty.

The purpose of this study was to identify the preoperative predictors of hospital length of stay after primary total knee arthroplasty in a patient population reflecting current trends toward shorter hospitalization and using readily obtainable factors that do not require scoring systems. A single-center, multi-surgeon retrospective chart review of two hundred and sixty consecutive patients who underwent primary total knee arthroplasty was performed. The mean length of stay was 3.0 days. Among the different variables studied, increasing comorbidities, lack of adequate assistance at home, and bilateral surgery were the only multivariable significant predictors of longer length of stay. The study was adequately powered for statistical analyses and the concordance index of the multivariable logistic regression model was 0.815.

Preoperative pain level and patient expectation predict hospital length of stay after total hip arthroplasty.

The purpose of this study was to identify preoperative predictors of length of stay after primary total hip arthroplasty in a patient population reflecting current trends toward shorter hospitalization and using readily obtainable factors that do not require scoring systems. A retrospective review of 112 consecutive patients was performed. High preoperative pain level and patient expectation of discharge to extended care facilities (ECFs) were the only significant multivariable predictors of hospitalization extending beyond 2 days (P=0.001 and P<0.001 respectively). Patient expectation remained significant after adjusting for Medicare's 3-day requirement for discharge to ECFs (P<0.001). The study was adequately powered to analyze the variables in the multivariable logistic regression model, which had a concordance index of 0.857.

Opioid-Based Analgesia: Impact on Total Joint Arthroplasty.

The objective of this study was to characterize the impact of opioid-based analgesia in total joint arthroplasty. The primary outcomes were incidence of in-hospital complications, length of stay, and discharge destination. Six hundred and seventy-three primary total hip and knee arthroplasties were retrospectively reviewed. The incidence of opioid-related adverse drug events was 8.5%, which accounted for 58.2% of all postoperative complications. Age, anesthesia technique, ASA score, and surgery type were significant risk factors for complications. After adjusting for these confounders, opioid-related adverse drug events were significantly associated with increased length of stay (P < 0.001) and discharge to extended care facilities (P = 0.014).

Medicare's 3-Day Rule: Time for a Rethink.

A pilot study was undertaken to examine the impact of Medicare's 3-day rule on length of stay (LOS). One hundred consecutive patients who underwent primary total joint arthroplasty and were discharged to extended care facilities were retrospectively reviewed. Based on readiness for discharge criteria, delaying discharge until the third postoperative day increased LOS by 1.1 days (P<0.001). 60.6% of patients were ready for discharge by the second postoperative day, none of whom required re-admission within 30 days of discharge. There were no rehabilitation gains by staying an additional hospital day beyond readiness for discharge (P=0.092). This pilot study calls into question the value of Medicare's 3-day rule and demonstrates the feasibility and need for further research to address this seemingly antiquated policy.

The Effect of Medical Education on Patient Satisfaction: An Asset or a Liability?

Few studies have investigated the influence of trainee involvement on inpatient satisfaction scores in the postoperative joint arthroplasty setting. This study compares Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey scores at academic and private health care centers to assess the impact of trainees on patient satisfaction. From 2013 to 2017, 3454 HCAHPS surveys were collected at the investigating institution from patients who underwent primary total hip and total knee arthroplasty. Surveys were categorized based on the inpatient practice setting-academic hospitals included orthopedic residents and medical students who were involved in perioperative care, whereas private settings did not have trainee involvement. Patient demographics, including age, body mass index, sex, and American Society of Anesthesiologists score, were retrospectively collected. A total of 2454 HCAHPS surveys from 2 academic hospitals and 1000 surveys from a private hospital were collected. Patients at the academic hospitals were more likely to report that symptoms to look out for were clearly explained (odds ratio, 1.882; P=.001), whereas patients from the private hospital were more likely to report that the hospital was always quiet at night (odds ratio, 1.271; P=.005). The overall satisfaction score was not significantly different between the academic and private settings (78.9 vs 80.2, respectively; P=.111). The overall hospital satisfaction score for patients undergoing primary total hip and knee arthroplasty was not significantly different between private and academic medical facilities. Thus, this study supports the idea that training future orthopedic surgeons will not negatively impact patient satisfaction scores in a way that affects reimbursement. [Orthopedics. 2022;45(5):276-280.].

Initial displacement of the intra-articular surface after articular fracture correlates with PTA in C57BL/6 mice but not "superhealer" MRL/MpJ mice.

Posttraumatic arthritis (PTA) occurs commonly after articular fracture and may arise, in part, from joint surface incongruity after injury. MRL/MpJ (MRL) "super-healer" mice are protected from PTA compared to C57BL/6 (B6) mice following articular fracture. However, the relationship between the initial displacement of the articular surface, biologic response, and susceptibility to PTA after fracture remains unclear. The objective of this study was to assess whether joint incongruity after articular fracture, as measured by in vivo micro-computed tomography (microCT), could predict pathomechanisms of PTA in mice. B6 and MRL mice (n = 12/strain) received a closed articular fracture (fx) of the left tibial plateau. Articular incongruity was quantified as bone surface deviations (BSD) for each in vivo microCT scan obtained from pre-fx to 8 weeks post-fx, followed by histologic assessment of arthritis. Serum concentrations of bone formation (PINP) and bone resorption (CTX-I) biomarkers were quantified longitudinally. Both strains showed increases in surface incongruity over time, as measured by increases in BSD. In B6 mice, acute surface incongruity was significantly correlated to the severity of PTA (R 2 = 0.988; p = .0006), but not in MRL mice (R 2 = 0.224; p = .220). PINP concentrations significantly decreased immediately post-fx in B6 mice (p = .023) but not in MRL mice, indicating higher bone synthesis in MRL mice. MRL/MpJ mice demonstrate a unique biologic response to articular fracture such that the observed articular bone surface displacement does not correlate with the severity of subsequent PTA. Clinical Relevance: Identifying therapies to enhance acute biologic repair following articular fracture may mitigate the risk of articular surface displacement for PTA.

Atraumatic Fracture of Cemented Vanguard Total Knee Arthroplasty Femoral Component.

The authors report the case of an atraumatic femoral component fracture 10 years after primary total knee arthroplasty (TKA) with a modern cemented fixed bearing system. The patient, a 70-year-old man, had the complication without inciting trauma, and he subsequently had severe pain and disability. This rare mode of TKA failure occurred at the superolateral aspect of the femoral component's anterior flange. At the time of revision, no femoral osteolysis was seen and the backside of the prosthesis fracture fragment was found to be free of cement. To the authors' knowledge, this is the first case of femoral component fracture in a Vanguard TKA (Biomet, Warsaw, Indiana), and the first case of fracture in a modern cobalt-chrome alloy femoral component associated with aseptic cement debonding. Femoral component stress fracture is a rare but serious complication of TKA. Reports of femoral component fracture in early designs were attributed to geometric design flaws, whereas modern TKA designs appear to fail when ingrowth failure, aseptic debonding, or osteolysis result in inadequate bony support of the prosthesis. Careful attention to bone cuts in porous-coated uncemented TKA systems and proper cementing technique in cemented TKA systems may preclude this rare complication. In the case of severe osteolysis, early revision may prevent catastrophic implant failure. [Orthopedics. 2020;43(5):e476-e479.].

Commercially Available Polymerase Chain Reaction Has Minimal Utility in the Diagnosis of Periprosthetic Joint Infection.

The use of genetic sequencing modalities in the diagnosis of periprosthetic joint infection (PJI) and the identification of organisms has gained popularity recently. Polymerase chain reaction (PCR) offers timely results for common organisms. The purpose of this study was to compare the accuracy of broad-range PCR, conventional culture, the Musculoskeletal Infection Society (MSIS) criteria, and the recently proposed criteria by Parvizi et al in the diagnosis of PJI. In this retrospective study, aspirate or tissue samples were collected in 104 revision and 86 primary arthroplasties for routine diagnostic workup for PJI and sent to the laboratory for PCR. Concordance along with statistical differences between diagnostic studies were calculated using chi-square test for categorical data. On comparison with the MSIS criteria, concordance was significantly lower for PCR at 64.7% compared with 86.3% for culture (P<.001). There was no significant difference based on diagnosis of prior infection (P=.706) or sample collection method (tissue swab or synovial fluid) (P=.316). Of the 87 patients who met MSIS criteria, only 20 (23.0%) PCR samples had an organism identified. In this series, PCR had little utility as a stand-alone test for the diagnosis of PJI, with a sensitivity of only 23.0% when using MSIS criteria as the gold standard. Polymerase chain reaction also appears to be significantly less accurate than culture in the diagnosis of PJI. Currently, several laboratory tests used for either criteria for PJI diagnosis should be obtained along with the overall clinical picture to help guide decision-making for PJI treatment. [Orthopedics. 2020;43(6):333-338.].

The Use of Modern Intramedullary Nailing in Distal Fibula Fracture Fixation.

Background. Lateral malleolus (LM) fixation is necessary for unstable ankle fractures. Traditional fixation relies on the use of plates through a lateral incision, wound healing can be an issue for such incisions. A novel intramedullary (IM) fixation device has been developed that can be placed through a minimal incision. The purpose of this study was to demonstrate the clinical efficacy of this device. Methods. A retrospective analysis was performed on patients who received IM fixation for isolated fibula, bimalleolar (BM), and trimalleolar (TM) fractures. Pertinent demographic information, operative factors, complications, and clinical outcomes were recorded. Results. Sixteen patients were included in the study with an average age of 59 years (range 35-86 years). Six patients presented with isolated LM fractures, four patients had a BM fracture with a syndesmotic injury, 2 patients sustained a LM fracture with an associated syndesmotic injury, 2 patients had a BM fracture, and 2 patients had a TM fracture with a syndesmotic injury. There was a 100% healing rate of the lateral malleolus without any cases of malunion or shortening. There were no cases of sural nerve or peroneal tendon injuries, nor any wound complications found. Conclusion. These findings demonstrate the safe and efficacious use of a novel intramedullary fixation device for fibula fractures with lower wound complications compared with published outcomes found with lateral fibular plating. The features of this device allow for reliable fixation of the fibula, maintaining length and minimizing wound issues. Levels of Evidence: Level IV: Case series.

Algorithm for Management of Periprosthetic Ankle Fractures.

BACKGROUND: Evidence on the management of and outcomes from periprosthetic fractures about a total ankle replacement (TAR) are limited. The purpose of this study was to develop an algorithm for the management of patients with postoperative periprosthetic fractures about a TAR. METHODS: This was a retrospective analysis of patients undergoing a TAR from 2007 through 2017 with a subsequent periprosthetic fracture >4 weeks from index surgery. Implant stability was defined radiographically and intraoperatively where appropriate. Univariate and multivariate analyses were used to identify differences in outcomes. Thirty-two patients were identified with a remote TAR periprosthetic fracture with an average follow-up of 26 months (range, 3-104 months). RESULTS: Most fractures were located about the medial malleolus (62.5%); the majority of fractures (75%) were deemed to have stable implants. Fractures of the talus always had unstable implants and always required revision TAR surgery (100%, P = .0002). There was no difference in patient-reported outcomes between stable and unstable fractures at an average of 36 months. In a multivariate analysis, fracture location (talus), less time to fracture, and implant type were found to be predictive of unstable implants ( P < .001). Implant stability was independently associated with the need for revision surgery ( P < .049). Nonoperative treatment was independently associated with treatment failure ( P < .001). CONCLUSION: The majority of stable fractures about a TAR required operative fixation. Management with immobilization was fraught with a high rate of subsequent surgical intervention. We found that fractures about the talus required revision TAR surgery or arthrodesis. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Current Evidence Does Not Support Medicare's 3-Day Rule in Primary Total Joint Arthroplasty.

Patients who undergo total joint arthroplasty and are destined for discharge to an extended-care facility--particularly Medicare beneficiaries--are required to have an inpatient stay of at least 3 consecutive days. The primary objective of this study was to explore the effect of this policy on length of stay. Secondary outcomes were 30-day readmission rate and inpatient rehabilitation gains. We retrospectively reviewed 284 consecutive cases of patients who underwent primary total hip or knee arthroplasty and were discharged to an extended-care facility. Based on readiness-for-discharge criteria, delaying discharge until postoperative day 3 increased length of stay by 1.08 days (P < .001) and had no effect on risk for 30-day readmission (P = .073). Although rehabilitation status improved with stays past discharge readiness (P = .038), the gains were not clinically sufficient to affect discharge destination. This study calls into question the validity of Medicare's 3-day rule in primary total joint arthroplasty. Larger, prospective, multicenter studies are needed to confirm these findings.

Does adjustable-loop femoral cortical suspension loosen after anterior cruciate ligament reconstruction? A retrospective comparative study.

BACKGROUND: Recent biomechanical research has suggested that adjustable-loop graft suspension constructs in anterior cruciate ligament (ACL) reconstruction may loosen after deployment. Our objective was to compare short-term knee stability and graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction. METHODS: A consecutive series of 188 patients who underwent primary ACL reconstruction using hamstrings autograft by a single surgeon were divided into two groups; 73 received adjustable-loop (TightRope RT (Arthrex Inc., Naples, FL)) and 115 received fixed-loop (RetroButton (Arthrex Inc., Naples, FL)) femoral cortical suspension. The two groups were compared at six months, one year, and two years postoperatively using KT-1000 arthrometer testing and graft failure rate (revision surgery, grade 2+ Lachman test, any pivot shift, >5mm side-to-side KT-1000 difference). RESULTS: There was no significant difference between the two groups in maximum side-to-side difference in KT-1000 testing at six months (mean 1.51mm (adjustable-loop group) vs. 1.79mm (fixed-loop group), p=0.23), one year (mean 1.44mm vs. 1.64mm, p=0.48), or two years (mean 1.14mm vs. 1.07mm, p=0.90) postoperatively. There was no significant difference between the two groups in rate of graft failure (10% vs. 11%, p=0.71) or timing of graft failure in affected patients (mean 11.4months vs. 13.8months, p=0.51). CONCLUSIONS: We found no significant difference in postoperative knee stability or graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction. Our results suggest that adjustable-loop suspension does not clinically loosen after ACL reconstruction. LEVEL OF EVIDENCE: III (retrospective cohort study).