Utilizing the Time Trade-Off, Standard Gamble, and Willingness to Pay Utility Measures to Evaluate Health-Related Quality of Life Prior to Knee or Hip Arthroplasty.

BACKGROUND: Time trade-off, standard gamble, and willingness to pay assess the number of years, risk of death, and income a patient would give up for perfect health. These questions were used to evaluate the impact knee arthritis, hip arthritis, or failed total knee (TKA) or hip arthroplasty (THA) has on patients' health-related quality of life prior to surgery. METHODS: Three hundred sixty patients including 176 undergoing primary TKA, 127 undergoing primary THA, 31 undergoing revision TKA, and 26 undergoing revision THA were assessed. Time trade-off and standard gamble were converted to utility scores with 1.0 suggesting perfect health and 0 suggesting preference for death rather than living in current state. Willingness to pay is the percentage of yearly income that a patient would pay for perfect health. RESULTS: The mean time trade-off, standard gamble, and willingness to pay scores were 0.74, 0.83, and 0.32 without significant difference between procedures with the numbers available for study (P = .16, .31, and 0.41, respectively). Increasing body mass index was correlated with decreasing time trade-off scores (P = .014). CONCLUSION: Patients scheduled for primary or revision THA and TKA would accept an average 17% risk of death, lose 2.6 years of an additional 10-year life expectancy, and pay 32% of their income for perfect health. The time trade-off (0.74) was similar to patients with history of acute myocardial infarction (0.74) or minor stroke (0.72) and worse than those with chronic hepatitis C (0.83) or human immunodeficiency virus/acquired immunodeficiency syndrome infection (0.86). These data highlight the high value that patients place on adult reconstructive procedures.

Nephrotoxicity After the Treatment of Periprosthetic Joint Infection With Antibiotic-Loaded Cement Spacers.

BACKGROUND: Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded cement spacer (ACS). The risk for acute kidney injury (AKI) related to use of antibiotic spacers has not been well defined. We aimed to identify the incidence of and risk factors for AKI after placement of an ACS. METHODS: We performed a prospective cohort study of patients with an infected primary total hip or knee arthroplasty treated with ACSs with vancomycin, gentamicin, and tobramycin. Serum creatinine and glomerular filtration rate data were collected at baseline and weekly intervals for 8 weeks. Patients were classified into Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) stages to determine incidence of AKI. Risk factors for kidney injury were identified via regression analysis. RESULTS: A total of 37 patients (20 total knee arthroplasty and 17 total hip arthroplasty) were included. During the 8 weeks after ACS placement, 10 patients (27%) fit RIFLE criteria for kidney injury and 2 patients (5%) fit RIFLE criteria for kidney failure. No baseline patient characteristics were associated with development of AKI. CONCLUSION: Patients should be monitored closely for development of AKI after placement of ACSs for the treatment of periprosthetic joint infection. Further research into minimizing risk for AKI is warranted.

Systemic Absorption of Antibiotics From Antibiotic-Loaded Cement Spacers for the Treatment of Periprosthetic Joint Infection.

BACKGROUND: Two-stage treatment of periprosthetic joint infections involves placement of high-dose antibiotic-loaded cement spacers (ACSs). Reports of ACS-induced nephrotoxicity have raised concern regarding systemic absorption of antibiotics after ACS placement. We sought to characterize the serum concentrations of antibiotics that occur after ACS placement. METHODS: We performed a prospective study of patients with an infected primary total hip (THA) or knee arthroplasty (TKA) treated with standardized ACSs with vancomycin, gentamicin, and tobramycin. Serum antibiotic levels were collected weekly for 8 weeks. RESULTS: Twenty-one patients (10 THA, 11 TKA) were included. Mean serum gentamicin levels ranged between 0.275±0.046 and 0.364±0.163 mg/L; mean serum tobramycin levels ranged from 0.313±0.207 to 0.527±0.424 mg/L; and mean serum vancomycin levels ranged from 5.46±6.6 to 15.34±9.6 mg/L. Serum antibiotic levels were detectable throughout the 8-week duration of ACS treatment. Regression analysis found that diabetes (coefficient 6.73, 95% CI 0.92-12.54, P < .05), blood urea nitrogen (coefficient 0.83, 95% CI 0.45-1.22, P < .001), number of cement doses (coefficient 3.71, 95% CI 0.76-6.66, P < .05), and use of systemic vancomycin (coefficient 6.24, 95% CI 2.72-9.75, P < .001) correlated with serum vancomycin levels. Patient age (coefficient -0.01, 95% CI -0.02 to 0, P < .01) and male sex (coefficient 0.20, 95% CI 0-0.41, P < .05) correlated with serum aminoglycoside level. CONCLUSION: Systemic absorption of antibiotics from high-dose ACS persists for at least 8 weeks. Patients should be monitored closely for complications related to systemic absorption of antibiotics from ACS treatment.

Continuous Adductor Canal Blocks Provide Superior Ambulation and Pain Control Compared to Epidural Analgesia for Primary Knee Arthroplasty: A Randomized, Controlled Trial.

BACKGROUND: Adductor canal blocks (ACBs) are an alternative to femoral nerve blocks that minimize lower extremity weakness. However, it is unclear whether this block will provide analgesia that is equivalent to techniques, such as epidural analgesia. The purpose of this randomized controlled trial was to compare continuous ACBs with epidural analgesia for primary total knee arthroplasty. METHODS: Following institutional review board approval, 145 patients were randomized to 1 of 3 groups: combined spinal-epidural (CSE), spinal + continuous ACB (CACB), or general + CACB. Epidural analgesia was used postoperatively in the CSE group, and an adductor canal catheter was used in the CACB groups. Power analysis determined that 84 patients per group were needed to demonstrate a 35% increase in ambulation with an alpha of 0.05 at a power of 90%. RESULTS: At interim analysis, 13 patients were removed for protocol deviations, leaving 45 in CSE, 41 in spinal + CACB and 46 in general + CACB groups. Patient demographics were similar in all comparisons suggesting appropriate randomization. Patients in the CACB groups walked further on postoperative day 1, 2, and 3 (P = .02). Mean daily pain scores were lower in the CACB groups (4.1 CSE, 3.0 spinal + CACB, 3.4 general + CACB, P = .009). There was no significant difference in total opioid consumption between groups (158 morphine equivalents CSE, 149 spinal + CACB, and 172 general + CACB). More patients reported being "very satisfied" in CACB groups (68% general + CACB, 63% spinal + CACB, and 36% CSE; P = .001). CONCLUSION: Continuous adductor analgesia provides superior ambulation, lower pain scores, faster discharge, and greater patient satisfaction when compared to epidural analgesia for primary total knee arthroplasty.

The Alpha-Defensin Test for Diagnosing Periprosthetic Joint Infection in the Setting of an Adverse Local Tissue Reaction Secondary to a Failed Metal-on-Metal Bearing or Corrosion at the Head-Neck Junction.

BACKGROUND: In patients with adverse local tissue reaction (ALTR) secondary to a failed metal-on-metal (MoM) bearing or corrosion at the head-neck junction in a metal-on-polyethylene bearing, ruling in or out periprosthetic joint infection (PJI) can be challenging. Alpha-defensin has emerged as an accurate test for PJI. The purpose of this multicenter, retrospective study was to evaluate the accuracy of the alpha-defensin synovial fluid test in detecting PJI in patients with ALTR. METHODS: We reviewed medical records of 26 patients from 3 centers with ALTR that had an alpha-defensin test performed. Patients were assessed for PJI using the Musculoskeletal Infection Society criteria. Thirteen of these subjects had MoM total hip arthroplasty, 9 had ALTR secondary to head-neck corrosion, and 4 had MoM hip resurfacing. RESULTS: Only 1 of the 26 patients met Musculoskeletal Infection Society criteria for infection. However, 9 hips were alpha-defensin positive, including 1 true positive and 8 that were falsely positive (31%). All 8 of the false positives were also Synovasure positive, although 5 of 8 had an accompanying warning stating the results may be falsely positive due to a low synovial C-reactive protein value. CONCLUSION: Similar to synovial fluid white blood cell count, alpha-defensin testing is prone to false-positive results in the setting of ALTR. Therefore, we recommend an aggressive approach to ruling out PJI including routine aspiration of all hips with ALTR before revision surgery to integrate the synovial fluid blood cell count, differential, cultures and adjunctive tests like alpha-defensin to allow for accurate diagnosis preoperatively.

The Mark Coventry, MD, Award: Oral Antibiotics Reduce Reinfection After Two-Stage Exchange: A Multicenter, Randomized Controlled Trial.

BACKGROUND: Many patients develop recurrent periprosthetic joint infection after two-stage exchange arthroplasty of the hip or knee. One potential but insufficiently tested strategy to decrease the risk of persistent or recurrent infection is to administer additional antibiotics after the second-stage reimplantation. QUESTIONS/PURPOSES: (1) Does a 3-month course of oral antibiotics decrease the risk of failure secondary to infection after a two-stage exchange? (2) Are there any complications related to the administration of oral antibiotics after a two-stage exchange? (3) In those patients who develop a reinfection, is the infecting organism different from the initial infection? METHODS: Patients at seven centers randomized to receive 3 months of oral antibiotics or no further antibiotic treatment after operative cultures after the second-stage reimplantation were negative. Adult patients undergoing two-stage hip or knee revision arthroplasty for a periprosthetic infection who met Musculoskeletal Infection Society (MSIS) criteria for infection at the first stage were included. Oral antibiotic therapy was tailored to the original infecting organism(s) in consultation with an infectious disease specialist. MSIS criteria as used by the treating surgeon defined failure. Surveillance of patients for complications, including reinfection, occurred at 3 weeks, 6 weeks, 3 months, 12 months, and 24 months. If an organism demonstrated the same antibiotic sensitivities as the original organism, it was considered the same organism; no DNA subtyping was performed. Analysis was performed as intent to treat with all randomized patients included in the groups to which they were randomized. A log-rank survival curve was used to analyze the primary outcome of reinfection. At planned interim analysis (enrollment is ongoing), 59 patients were successfully randomized to the antibiotic group and 48 patients to the control group. Fifty-seven patients had an infection after TKA and 50 after a THA. There was no minimum followup for inclusion in this analysis. The mean followup was 14 months in the antibiotic group and 10 months in the control group. RESULTS: Patients treated with oral antibiotics failed secondary to infection less frequently than those not treated with antibiotics (5% [three of 59] versus 19% [nine of 48]; hazard ratio, 4.37; 95% confidence interval, 1.297-19.748; p = 0.016). Three patients had an adverse reaction to the oral antibiotics severe enough to cause them to stop taking the antibiotics early, and four patients who were randomized to that group did not take the antibiotics as directed. With the numbers available, there were no differences between the study groups in terms of the likelihood that an infection after treatment would be with a new organism (eight of nine in the control group versus one of three in the treatment group, p = 0.087). CONCLUSIONS: This multicenter randomized trial suggests that at short-term followup, the addition of 3 months of oral antibiotics appeared to improve infection-free survival. As a planned interim analysis, however, these results may change as the study reaches closure and the safety profile may yet prove risky. Further followup of this cohort of patients will be necessary to determine whether these preliminary results are durable over time. LEVEL OF EVIDENCE: Level I, therapeutic study.

Poor Outcomes of Irrigation and Debridement in Acute Periprosthetic Joint Infection With Antibiotic-Impregnated Calcium Sulfate Beads.

BACKGROUND: One proposed strategy to increase the success of irrigation and debridement with implant retention for the treatment of acute periprosthetic joint infection (PJI) is the use of dissolvable antibiotic-impregnated calcium sulfate beads to provide a local depot of antibiotics. The purpose of this study was to evaluate the outcome of such an approach. METHODS: Thirty-two patients with acute hematogenous (18 patients; 1 bilateral) or acute postoperative (14 patients) PJIs who underwent irrigation and debridement with implant retention and addition of antibiotic-impregnated calcium sulfate beads were retrospectively reviewed. PJI followed 27 total knee arthroplasties and 6 total hip arthroplasties. The most common infecting organisms were methicillin-sensitive Staphylococcus aureus (13 of 33) and Streptococcus (9 of 33). The primary outcome parameter was recurrence of infection according to the Musculoskeletal Infection Society criteria. Patients were followed up for a minimum of 3 months or until failure. RESULTS: At a mean of 12.7 months (range, 3-30 months), 16 of the 33 patients failed (48%). Acute hematogenous and acute postoperative PJI had similar failure rates at 47% and 50%, respectively (P = .88). Seven failures required a 2-stage exchange, while 8 patients were treated with chronic antibiotic suppression, being unwilling or unable to undergo further surgical intervention. CONCLUSION: The addition of antibiotic-impregnated calcium sulfate beads does not appear to improve outcomes of irrigation and debridement with implant retention in the setting of acute hematogenous or acute postoperative PJI. Given the short follow-up in this report, this represents a best-case scenario and the overall failure rate may be higher with further follow-up.

Incidence, Risk Factors, and Clinical Implications of Pneumonia Following Total Hip and Knee Arthroplasty.

BACKGROUND: The purpose of this study is to determine the incidence, risk factors, and clinical implications of pneumonia following total joint arthroplasty (TJA). METHODS: The American College of Surgeons National Surgical Quality Improvement Program was used to conduct a retrospective cohort study of patients undergoing TJA. Independent risk factors for the development of pneumonia within 30 days of TJA were identified using multivariate regression. Mortality and readmission rates were compared between patients who did and did not develop pneumonia. Multivariate regression was used to adjust for all demographic, comorbidity, and procedural characteristics. RESULTS: In total, 171,200 patients met inclusion criteria, of whom 66,493 (38.8%) underwent THA and 104,707 (61.2%) underwent TKA. Of the 171,200 patients, 590 developed pneumonia, yielding a rate of 0.34% (95% confidence interval = 0.32%-0.37%). Independent risk factors for pneumonia were chronic obstructive pulmonary disease, diabetes mellitus, greater age (most notably ≥80 years), dyspnea on exertion, dependent functional status, lower body mass index, hypertension, current smoker status, and male sex. The subset of patients who developed pneumonia following discharge had a higher readmission rate (82.1% vs 3.4%, adjusted relative risk [RR] = 16.6, P < .001) and a higher mortality rate (3.7% vs 0.1%, adjusted RR = 19.4, P < .001). Among 124 total mortalities, 22 (17.7%) occurred in patients who had developed pneumonia. CONCLUSION: Pneumonia is a serious complication following TJA that occurs in approximately 1 in 300 patients. Approximately 4 in 5 patients who develop pneumonia are subsequently readmitted, and approximately 1 in 25 die. Given the serious implications of this complication, evidence-based pneumonia prevention programs including oral hygiene with chlorhexidine, sitting upright for meals, elevation of the head of the bed to at least 30°, aggressive incentive spirometry, and early ambulation should be considered for patients at greatest risk.

Periprosthetic Joint Infection After Hip and Knee Arthroplasty: A Review for Emergency Care Providers.

Periprosthetic joint infection is among the most common modes of failure of a total hip or knee arthroplasty and can be a common concern when patients present to the emergency department for care. The initial evaluation for periprosthetic joint infection includes a history and physical examination, followed by radiographs (to rule out other causes of pain or failure) and then serum erythrocyte sedimentation rate and C-reactive protein testing. If the erythrocyte sedimentation rate and C-reactive protein level are elevated or if the clinical suspicion for infection is high, the joint should be aspirated and the fluid sent for culture, as well as for a synovial WBC count and differential, with optimal threshold values of 3,000 WBC/µL and 80% polymorphonuclear cells, respectively. Recent work has shown that optimal cutoff values for patients presenting in the early postoperative period (within the first 6 weeks postoperatively) are different, with a C-reactive protein level greater than or near 100 mg/L (normal <10 mg/L), indicating the need for aspiration, with synovial fluid WBC thresholds of 10,000 WBC/µL and 90% polymorphonuclear cells. Antibiotics should not be administered before joint aspiration unless the patient has systemic signs of sepsis because even a single dose may cloud the interpretation of subsequent tests, including cultures taken from the joint. Furthermore, superficial cultures taken from wound drainage are discouraged because they can similarly cloud diagnosis and treatment. The rising prevalence of total joint arthroplasty makes proficiency in the assessment and early management of periprosthetic joint infection important for the emergency physician to optimize clinical outcomes.

Cross-sectional area of the longus colli and cervical degenerative spondylolisthesis: A retrospective review evaluating this anatomic consideration.

Background: Limited literature is available to define the impact of the longus colli muscle, a deep flexor of the spine, on cervical spine stability despite its close proximity to the vertebrae. Aims and Objectives: The purpose of this study was to determine if longus colli cross-sectional area (CSA) is associated with the severity preoperative cervical degenerative spondylolisthesis. Materials and Methods: Patients undergoing elective anterior cervical discectomy and fusion (ACDF) for cervical spondylolisthesis between 2010-2021 were retrospectively identified. Longus colli cross-sectional areas (CSA) were measured from preoperative MRI images at the C5 level. Preoperative spondylolisthesis measurements were recorded with cervical radiographs. Patients were grouped by quartiles respectively according to longus colli CSAs. Statistical tests compared patient demographics, surgical characteristics, and surgical outcomes between groups. Multiple linear regression analysis was utilized to assess if longus colli CSA predicted cervical spondylolisthesis. Results: A total of 157 patients met inclusion criteria. Group 1 (first quartile) was the oldest (60.4 ± 12.0 years, P = 0.024) and was predominantly female (59.0%, P = 0.001). Group 1 also had the highest maximum spondylolisthesis (0.19 mm, P = 0.031) and highest proportion of grade 2 spondylolisthesis (23.1%, P = 0.003). On regression analysis, lowest quartile of longus colli CSA was an independent predictor of larger measured maximum spondylolisthesis (ß: 0.04, P = 0.012). Conclusion: Smaller longus colli CSA is independently associated with a higher grade and degree of preoperative cervical spondylolisthesis, but this finding does not result in adverse postsurgical outcomes.

Postoperative Glycemic Variability and Adverse Outcomes After Posterior Cervical Fusion.

INTRODUCTION: Posterior cervical decompression and fusion (PCDF) is a procedure commonly performed to help alleviate symptoms and improve quality of life in patients experiencing cervical spondylotic myelopathy, multilevel stenosis, and cervical deformity. Although various risk factors have been linked to adverse outcomes in patients after PCDF, this is the first study that specifically explores postoperative glycemic variability and its association with adverse outcomes. METHODS: A retrospective cohort study was conducted with a total of 264 patients after PCDF procedures that had available postoperative blood glucose measurements. Patients were divided into tertiles based on their coefficient of variation as an indicator of glycemic variability. Outcomes measured included inpatient complications, length of stay (LOS), 90-day readmission, revision, and surgical site infection rates. RESULTS: Results showed a significant difference in glycemic variability among tertiles with respect to LOS (P = 0.01). The average LOS for the first, second, and third tertiles was 3.90 (3.20, 4.59), 5.73 (4.45, 7.00), and 6.06 (4.89, 7.22), respectively. Logistic regression analysis showed significantly higher odds of readmission (odds ratio: 4.77; P = 0.03) and surgical site infections (odds ratio: 4.35; P = 0.04) in the high glycemic variability group compared with the low glycemic variability group within 90 days of surgery. No significant difference was noted among tertiles with respect to inpatient complications. DISCUSSION: This study establishes a relationship between postoperative glycemic variability and LOS, as well as 90-day readmission and surgical site infection rates after PCDF. Our results suggest that limiting fluctuations in blood glucose levels may curtail inpatient healthcare costs related to in-hospital stay. Although immediate postoperative glycemic variability is ultimately acceptable, before discharge, proper glucose management plans should be in place to help prevent adverse patient outcomes.

The Outcomes of Patients With Neck Pain Following ACDF: A Comparison of Patients With Radiculopathy, Myelopathy, or Mixed Symptomatology.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The goal of the present study was to determine whether neck pain responds differently to anterior cervical discectomy and fusion (ACDF) between patients with cervical radiculopathy and/or cervical myelopathy. SUMMARY OF BACKGROUND DATA: Many patients who undergo ACDF because of radiculopathy/myelopathy also complain of neck pain. However, no studies have compared the response of significant neck pain to ACDF. METHODS: Patients undergoing one to three-level primary ACDF for radiculopathy and/or myelopathy with significant (Visual Analogue Scale [VAS] ≥ 3) neck pain and a minimum of 1-year follow-up were included. Based on preoperative symptoms patients were split into groups for analysis: radiculopathy (R group), myelopathy (M group), or both (MR group). Groups were compared for differences in Health Related Quality of Life outcomes: Physical Component Score-12, Mental Component Score (MCS)-12, Neck Disability Index, VAS neck, and VAS arm pain. RESULTS: Two hundred thirty-five patients met inclusion criteria. There were 117 patients in the R group, 53 in the M group, and 65 in the MR group. Preoperative VAS neck pain was found to be significantly higher in the R group versus M group (6.5 vs. 5.5; P = 0.046). Postoperatively, all cohorts experienced significant (P < 0.001) reduction in VAS neck pain, (ΔVAS neck; R group: -2.9, M: -2.5, MR: -2.5) with no significant differences between groups. However, myelopathic patients showed greater improvement in absolute MCS-12 scores (P = 0.011), RR (P = 0.006), and % minimum clinically important difference (P = 0.013) when compared with radiculopathy patients. This greater improvement remained following regression analysis (P = 0.025). CONCLUSION: Patients with substantial preoperative neck pain experienced significant reduction in their neck pain, disability, and physical function following ACDF, whether treated for radiculopathy or myelopathy. However, in this study, only myelopathy patients had significant improvements in their mental function as represented by MCS improvements. LEVEL OF EVIDENCE: 3.

Oral and Intravenous Tranexamic Acid Are Equivalent at Reducing Blood Loss Following Total Hip Arthroplasty: A Randomized Controlled Trial.

BACKGROUND: Tranexamic acid is an antifibrinolytic that has been shown to reduce blood loss and the need for transfusions when administered intravenously in total hip arthroplasty. Oral formulations of the drug are available at a fraction of the cost of the intravenous preparation. The purpose of this randomized controlled trial was to determine if oral and intravenous formulations of tranexamic acid have equivalent blood-sparing properties. METHODS: In this double-blinded trial, 89 patients undergoing primary total hip arthroplasty were randomized to receive 1.95 g of tranexamic acid orally 2 hours preoperatively or a 1-g tranexamic acid intravenous bolus in the operating room prior to incision; 6 patients were eventually excluded for protocol deviations, leaving 83 patients available for study. The primary outcome was the reduction of hemoglobin concentration. Power analysis determined that 28 patients were required in each group with a ±1.0 g/dL hemoglobin equivalence margin between groups with an alpha of 5% and a power of 80%. Equivalence analysis was performed with a two one-sided test (TOST) in which a p value of <0.05 indicated equivalence between treatments. RESULTS: Forty-three patients received intravenous tranexamic acid, and 40 patients received oral tranexamic acid. Patient demographic characteristics were similar between groups, suggesting successful randomization. The mean reduction of hemoglobin was similar between oral and intravenous groups (3.67 g/dL compared with 3.53 g/dL; p = 0.0008, equivalence). Similarly, the mean total blood loss was equivalent between oral and intravenous administration (1,339 mL compared with 1,301 mL; p = 0.034, equivalence). Three patients (7.5%) in the oral group and one patient (2.3%) in the intravenous group were transfused, but the difference was not significant (p = 0.35). None of the patients in either group experienced a thromboembolic event. CONCLUSIONS: Oral tranexamic acid provides equivalent reductions in blood loss in the setting of primary total hip arthroplasty, at a greatly reduced cost, compared with the intravenous formulation. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.