Durability of Primary Total Hip Arthroplasty With Cementless Stems Without a Collar in Elderly Patients Age 75 Years and Over.

BACKGROUND: Cementless femoral fixation in total hip arthroplasty (THA) has increased in prevalence worldwide. However, cementless fixation in elderly patients is controversial due to the risks of periprosthetic fracture and aseptic loosening. This study evaluated outcomes in patients undergoing primary THA utilizing a cementless stem without a collar, comparing those less than 75 years to those older than 75 years. METHODS: Between 2011 and 2021, there were 2,605 cementless THAs performed by 4 surgeons utilizing a highly porous metal fixation surface without a collar and consistent clinical protocols. There were 469 patients who had an age ≥ 75 years. Revision rates, intraoperative fractures, and 90-day mortality were compared between cohorts. In the ≥ 75 year age group, there were more women, more American Society of Anesthesiologists physical status classification III or IV, a lower body mass index, and more kidney disease, osteoporosis, and thyroid disease (P ≤ .002). RESULTS: All-cause revision rates trended lower for the ≥75 year age group compared to < 75 year (1.9 versus 3.5%, P = .082) at 20-months of follow-up. Moreover, there was no difference in all-cause femoral component revisions comparing ≥ 75 to < 75 year age groups (1.5 versus 2.2%, P = .375), with only 3 of 10 femoral revisions due to aseptic loosening being in the ≥ 75 year age group. Intraoperative fracture (0.2 versus 0.5%, P = .701) and 90-day mortality (0.2 versus 0.1%, P = .460) did not differ between ≥ 75 and < 75 year age groups. CONCLUSIONS: Older patients had comparable revision rates compared to younger patients using cementless femoral fixation without a collar. Furthermore, there was no difference in 90-day mortality or intraoperative fracture rates. Study findings provide evidence for the safety and durability of cementless THA using collarless femoral stems in elderly patients ≥ 75 years of age. LEVEL OF EVIDENCE: III.

Implant Position, Survivorship, and Patient-Reported Outcomes in Manual Medial Unicompartmental Knee Arthroplasty.

BACKGROUND: Two related recent reports described high error rates for implant positioning and reduced implant survivorship in manual unicompartmental knee arthroplasty (MUKA) compared to robotic-assisted unicompartmental knee arthroplasty (RUKA). The present study scientifically replicated these reports by comparing MUKAs similarly performed by an experienced high-volume surgeon in similar patients using the same study methods as these reports. METHODS: A total of 216 consecutive MUKAs were retrospectively evaluated radiographically for achievement of implant positioning targets. Achievement of targets was compared to the published MUKA and RUKA outcomes and correlated with revision rates and patient-reported outcome measures. RESULTS: There were 20% of study MUKAs compared to 88.1% of comparison MUKAs (P < .001) and 31.4% of comparison RUKAs (P < .048) that failed to meet all 7 implant positioning targets. The MUKA revision rates were significantly lower in the study sample than for comparison MUKAs (3.2% versus 14.2%, P < .001). Implant survivorship was 91.7% (95% confidence interval 84.9, 98.5%) at 8.9 years compared to 70.0% (95% confidence interval 56.0, 80.0%) at 10.2 years, respectively. Most patient-reported outcome measures did not differ based on achievement of implant positioning targets (P ≥ .072). CONCLUSIONS: Present study findings indicate that observations in the 2 recent reports may not be generalizable to all UKA surgeons. Additional data on the relationship between implant positioning and revision as well as functional outcomes are needed to identify appropriate robotic arthroplasty applications.

Predictors of Failure to Achieve Planned Same-Day Discharge after Primary Total Joint Arthroplasty: a Multivariable Analysis of Perioperative Risk Factors.

INTRODUCTION: Failure to achieve planned same-day discharge (SDD) primary total joint arthroplasty (TJA) occurs in as many as 7% to 49% of patients in the United States. This study evaluated the association between 43 perioperative risk factors and SDD failure rates. METHODS: A retrospective analysis of prospectively collected data from 466 primary TJAs with planned SDD to home was performed. Surgeries were performed at an academic tertiary care center comprising a hospital facility and a stand-alone ambulatory surgery center (ASC) on the same campus. Factors associated with failed SDD were identified using a multivariable analysis. RESULTS: Only one of 316 (0.3%) patients who underwent surgery in the ASC failed planned SDD ( P < 0.001) compared with 33.3% of 150 patients who underwent surgery in the hospital. The ASC failure was because of pain that interfered with physical therapy. Sixty-two percent (n = 31) of hospital failures were attributed to medical complications, 24% (n = 12) to physical therapy clearance, 8% (n = 4) to not being seen by internal medicine or therapy on the day of surgery, and 6% (n = 3) to unknown causes. Failure was increased in patients with preoperative anemia ( P = 0.003), nonwhite patients ( P = 0.002), patients taking depression/anxiety medication ( P = 0.015), and for every 10-morphine milligram equivalent increase in opioids consumed per hour in the postacute care unit ( P = 0.030). DISCUSSION: Risk stratification methods used to allocate patients to ASC versus hospital outpatient TJA surgery predicted SDD success. Most failures were secondary to medical causes. The findings of this study may be used to improve perioperative protocols enabling the safe planning and selection of patients for SDD pathways.

Go Big or Go Home: Obesity and Total Joint Arthroplasty.

Obesity is highly prevalent, and it is expected to grow considerably in the United States. The association between obesity and an increased risk of complications following total joint arthroplasty (TJA) is widely accepted. Many believe that patients with body mass index (BMI) >40 have complications rates that may outweigh the benefits of surgery and should consider delaying it. However, the current literature on obesity and outcomes following TJA is observational, very heterogeneous, and full of confounding variables. BMI in isolation has several flaws and recent literature suggests shifting from an exclusively BMI <40 cutoff to considering 5 to 10% preoperative weight loss. BMI cutoffs to TJA may also restrict access to care to our most vulnerable, marginalized populations. Moreover, only roughly 20% of patients instructed to lose weight for surgery are successful and the practice of demanding mandatory weight loss needs to be reconsidered until convincing evidence exists that supports risk reduction as a result of preoperative weight loss. Obese patients can benefit greatly from this life-changing procedure. When addressing the potential difficulties and by optimizing preoperative assessment and intraoperative management, the surgery can be conducted safely. A multidisciplinary patient-centered approach with patient engagement, shared decision-making, and informed consent is recommended.

Effect of Tobacco Use on Radiolucent Lines in Modern Cementless Total Knee Arthroplasty Tibial Components.

Background: The link between tobacco consumption and wound complications following total knee arthroplasty (TKA) is well established. However, the effect of tobacco use on biologic fixation in cementless TKA remains unknown. This study evaluated the influence of tobacco use on the presence of radiolucent lines of tibial components in cementless TKA. Methods: A total of 293 consecutive cementless TKAs of 2 contemporary designs were retrospectively reviewed. Tibial radiolucent lines and component alignment were measured using an established measurement protocol. Patients with any history of tobacco use or active tobacco use (tobacco users) were compared to those with no history of tobacco use (tobacco nonusers). No significant differences which influenced outcomes were detected between the tobacco user and tobacco nonuser groups (P ≥ .071). Results: Radiolucent lines decreased from 1-month to latest follow-up (mean 2.5 years) in all 10 radiographic zones regardless of tobacco use (P ≤ .084). However, evaluating intrapatient change in radiolucent line width, the tobacco nonuser group had more radiolucent lines resolve by the latest follow-up in nearly all radiographic zones, although most differences did not reach statistical significance, except for anteroposterior zone 1 (-31% vs -19%, P = .022). No tibial components were revised for aseptic loosening. Conclusions: Results from this study suggest that any tobacco use prior to cementless TKA has the potential to hinder biologic fixation of tibial components. While no tibial components were revised for aseptic loosening, follow-up was relatively short at 2.5 years and therefore warrants further study to discern the effect of persistent radiolucent lines on long-term fixation.

Comparison of the biomechanical stability of transverse and oblique screw trajectories in retrograde intramedullary nailing of supracondylar femur fractures.

BACKGROUND: The goal was to determine the effect of addition of oblique trajectory distal interlock screws to a retrograde intramedullary femoral nail on implant stability (stiffness), cycles to failure and mode of failure. The hypothesis was that addition of oblique screws would increase implant stability and number of loading cycles to failure. METHODS: Eight matched pairs were tested; one femur implanted with a femoral nail with only transverse distal interlock screws and the other with transverse and oblique interlock screws. Axial compressive load was applied to the femoral head and the gluteal tendon was tensioned vertically to simulate standing or at 45° to the sagittal plane to simulate stair climbing. Loads were cycled to increasing amplitude until failure of fixation (10 mm displacement or 10° rotation). FINDINGS: In simulated standing, oblique screw specimen had greater sagittal bending (bowing) than transverse only specimen. Transverse (axial) plane motion was higher in simulated stair climbing in oblique screw specimen. Oblique screw specimen had higher sagittal plane translation at 600 N of load. At 300 N, oblique screw specimen had lower internal-external rotation than transverse only specimen. A larger number of cycles to failure were observed in four oblique screw of seven paired specimen. Failure (10 mm or 10 degrees of motion) was only achieved during simulated stair climbing. INTERPRETATION: Our hypothesis that adding oblique screws improves fixation was rejected. Activities of daily living other than standing may constitute a challenge to fracture fixation; fixation failure occurred at lower loads in simulated stair climbing than standing.

Erratum to 'Adverse Local Tissue Reaction Due to Acetabular Corrosion in Modular Dual-Mobility Constructs' [Arthroplasty Today 6 (2020) 976-980].

[This corrects the article DOI: 10.1016/j.artd.2020.08.002.].

No Difference in Dislocation Rates Comparing Large Diameter Jumbo Femoral Heads and Dual-Mobility Bearings in Revision Total Hip Arthroplasty.

BACKGROUND: Dual-mobility (DM) bearings reduce instability in revision total hip arthroplasty (THA); however, DM bearings are costly and reports of corrosion have recently emerged. Furthermore, no study has compared DM to standard bearings with large diameter femoral heads ≥40-mm. This study's purpose was to compare postoperative dislocation rates of standard and DM bearings with large femoral heads after revision THA. METHODS: A retrospective review of 301 consecutive revision THAs was performed. The mean follow-up was 37.1 months. To isolate the effect of the double articulation, standard and DM bearings with femoral heads ≥40-mm were compared. Outcomes were postoperative dislocation and reoperation within 90 days. RESULTS: The cohort consisted of 182 standard bearings and 75 DM bearings. There were no differences in revision indication comparing standard and DM bearings (P = .258). Overall dislocation rate was 8.6% (22 of 257). The dislocation rate was 5.7% for standard bearings with ≥40-mm femoral heads compared with 6.9% in DM bearings with ≥40-mm femoral heads (P = 1.000). In multivariate analysis, lower body mass index (odds ratio 1.72), female sex (odds ratio 2.01), and decreased outer femoral head diameter-to-cup component size ratio (odds ratio 1.64) were predictors of postoperative dislocation regardless of bearing type. CONCLUSION: This study showed no difference in dislocation rates between standard and DM bearings when comparing similar femoral head diameters of ≥40-mm used in revision THAs. Considering the cost and potential deleterious issues associated with additional interfaces, DM bearings should be used judiciously considering similar results may be achieved with single-articulation bearings using large femoral heads. LEVEL OF EVIDENCE: Level III.

Utility and Prognostic Ability of a Diagnostic Injection Before Revision Total Knee Arthroplasty.

BACKGROUND: Diagnostic injections are commonly utilized in the workup of painful total knee arthroplasties (TKA), particularly when the diagnosis remains unclear. However, current literature provides limited evidence regarding the utility and prognostic capability of anesthetic injections in this scenario. This study sought to establish the role of diagnostic injections in predicting successful revision TKA. METHODS: A retrospective review was conducted on 144 consecutive aseptic revision TKAs receiving diagnostic anesthetic injections. Instability (57.6%) and aseptic loosening (33.3%) comprised most revision etiologies. Patient-reported percentage pain relief after the injection was statistically correlated with KOOS JR, Knee Society Score, UCLA Activity Level, and satisfaction scores. RESULTS: About 74.3% (107/144) of revision TKAs reported >50% pain relief after injection. There were no differences in pain relief based on revision indication (P = .841). Improvement from preoperative activity level was greater in the >50% pain relief group (P = .024). Four-month patient satisfaction did not differ between patients who reported >50% and ≤50% pain relief (67% vs. 66%, P = .130). About 64% of patients who reported >50% pain relief were satisfied at minimum 1-year follow-up, compared with only 47% of those who reported ≤50% pain relief after diagnostic injection (P < .001). CONCLUSION: Study results show that patients reporting >50% pain relief after diagnostic injection have improvements in activity level and maintain greater satisfaction at minimum 1-year than those reporting ≤50% pain relief. Expectations for improvement after revision TKA should be tempered if diagnostic anesthetic injection yields minimal subjective pain relief.

Does Patellofemoral Disease Affect Outcomes in Contemporary Medial Fixed-Bearing Unicompartmental Knee Arthroplasty?

BACKGROUND: Pre-existing patellofemoral disease has traditionally been a contraindication to unicompartmental knee arthroplasty (UKA), as proposed by Kozinn and Scott. More recently, some propose that patellofemoral disease can be ignored in UKA; however, the supporting research is predominantly in mobile-bearing designs. The study purpose was to evaluate the effect of patellofemoral disease osteoarthritis severity on latest outcomes after fixed-bearing medial UKA. METHODS: A retrospective review of 147 consecutive medial fixed-bearing UKAs with minimum 1-year follow-up was performed. The medial and lateral patellofemoral compartments were graded according to the Kellgren & Lawrence grading system, Osteoarthritis Research Society International atlas, and intraoperative assessment performed using the Outerbridge classification. Prospectively collected University of California Los Angeles Activity Level, modern Knee Society pain and function scores, and Likert scale satisfaction were correlated with presence and severity of pre-existing patellofemoral disease. RESULTS: One hundred forty-three medial UKAs were analyzed with mean age, body mass index, and follow-up of 64.1 years, 30.7 kg/m2, and 24.0 months, respectively. No correlations were observed between patellofemoral disease severity and patient-reported outcome measures at latest follow-up or improvement scores for Kellgren & Lawrence grading system or Osteoarthritis Research Society International atlas (P ≥ .058). Improvement in activity level scores was significantly higher for patients with less patellar and trochlear chondral damage despite not reaching minimal clinically important difference of 2.0 (P ≤ .028). Regardless of patellofemoral disease severity, 93% of UKAs were satisfied or very satisfied. CONCLUSION: Clinical outcomes of fixed-bearing medial UKA were not adversely impacted by intraoperatively visualized or radiographically evaluated patellofemoral disease. Furthermore, long-term follow-up is warranted and caution should be used before considering patellofemoral disease as a contraindication for UKA.

Early failure of sequentially annealed polyethylene in total knee arthroplasty.

Improvements in the processing of polyethylene have led to a dramatic reduction in wear rates in total hip arthroplasty. This led to the adoption of modern highly cross-linked polyethylene in total knee arthroplasty (TKA). However, the differences in modes of wear and failure between total hip arthroplasty and TKA have tempered expectations regarding similar decreases in polyethylene-related complications in TKA. We present a case of early catastrophic failure of a modern sequentially irradiated and annealed highly cross-linked polyethylene insert only 5 years after contemporary cementless TKA.

Adverse Local Tissue Reaction due to Acetabular Corrosion in Modular Dual-Mobility Constructs.

Dual-mobility (DM) bearings in total hip arthroplasty (THA) have been reported to reduce dislocation rates, especially in high-risk patients, and are being rapidly adopted in primary and revision THAs. However, this technology introduces additional interfaces that have the potential to result in unforeseen complications. We present a series of 3 patients with mechanically assisted crevice corrosion at the acetabular component-metal dual-mobility liner interface. Consequently, we urge judicious use and close clinical observation of this new, effective technology in THA.

Effect of Preoperative Dental Extraction on Postoperative Complications After Total Joint Arthroplasty.

BACKGROUND: Poor dental hygiene has historically been considered a potential risk factor for infection in total joint arthroplasty (TJA), which has resulted in the common practice of requiring preoperative dental clearance and often results in dental extractions. However, the association between dental pathology and periprosthetic joint infection (PJI) has recently been called into question. METHODS: A consecutive series of 2457 primary total hip and total knee arthroplasties were retrospectively reviewed. Documented dental evaluation was found in 1944 (79.1%) procedures, 223 (11.5%) of which had extraction of at least 1 tooth. No documented dental evaluation was found in 369 (15.0%) patients. RESULTS: The overall complication rate was 3.87% with an overall PJI rate of 1.51%. There was no statistically significant association between a complication and procedure type, sex, preoperative dental evaluation or extraction, diabetes status, immunosuppression, malnutrition, or age. However, our sample demonstrated a higher complication rate among patients undergoing dental extraction as well as for those with diabetes and immunosuppressed patients. CONCLUSION: Our findings suggest that routine formal dental clearance for all TJA patients may not be necessary. Additionally, patients with poor oral hygiene may not have elevated risk of postoperative PJI, and preoperative tooth extraction may represent an unnecessary step for patients undergoing elective TJA.

The Effect of Proton Pump Inhibitors on Bone Formation in a Rat Spinal Arthrodesis Model.

STUDY DESIGN: Rat posterolateral arthrodesis model. OBJECTIVE: Quantify the impact of administration of a proton pump inhibitor on spine fusion. SUMMARY OF BACKGROUND DATA: Proton pump inhibitors (PPIs) are widely used for gastrointestinal disorders and for ulcer prophylaxis in patients taking non-steroidal anti-inflammatory drugs. PPIs cause chronic acid suppression which has been found to result in decreased bone mineral density, increased fracture risk, and impaired fracture healing. Despite advances in surgical techniques, pseudarthrosis still occurs in up to 24% of patients requiring revision surgery following spinal fusion procedures. Thus, there are likely many unidentified risk factors. While PPIs have been hypothesized to impact fracture healing, no study has evaluated their effect on spine arthrodesis rates. METHODS: Thirty-eight female rats underwent posterolateral lumbar spinal fusion. Rats were divided into two groups: normal saline control and pantroprazole, which was administered by daily intraperitoneal injections. At 8 weeks postoperative spines were evaluated with manual palpation, microCT, histologic analysis, and biomechanical testing. RESULTS: Fusion rates of the control group and PPI group were not significantly different (100% vs. 94%). Average fusion scores were significantly lower in the pantoprazole group. New bone formation identified on microCT imaging of bilaterally fused specimens demonstrated a lower average volume of newly generated bone in the PPI group, but this difference was not significant. Biomechanical testing demonstrated no significant difference in strength or stiffness of the fusion mass between the groups. CONCLUSION: This study demonstrates that administration of PPIs does not inhibit fusion rates, bone formation, or affect biomechanical integrity of fusion. However, lower fusion scores in the PPI group suggest that a negative impact may still exist. Future studies will explore growth factor and protein expression in the fusion masses as well as utilize higher doses of PPI to fully discern their effect on spine fusion. LEVEL OF EVIDENCE: N/A.

The effect of vancomycin powder on bone healing in a rat spinal rhBMP-2 model.

OBJECTIVE This study aims to quantify the impact of vancomycin powder application on new bone formation and spine fusion rates in a rat posterolateral arthrodesis model. METHODS Thirty-six female Sprague-Dawley rats underwent a posterolateral lumbar spinal fusion (PLF) at the L-4 and L-5 vertebrae. Fusion was elicited via implantation of an absorbable collagen sponge containing 3 µg rhBMP-2. Rats were divided into 3 groups: no vancomycin (control), standard-dose vancomycin, and high-dose vancomycin, based on what was applied to the fusion bed. Clinical studies typically describe the application of 1 g vancomycin into the surgical wound. Presuming an average individual patient weight of 70 kg, a weight-based equivalent dose of vancomycin powder was applied subfascially in the PLF model constituting a "standard-dose" treatment group (14.3 mg/kg, n = 12). To determine whether there is a critical threshold beyond which vancomycin increases the risk of pseudarthrosis, a 10-fold higher dose was administered to a "high-dose" treatment group (143 mg/kg, n = 12). No vancomycin powder was applied to the surgical site in the control group (n = 12). Fusion was evaluated with plain radiographs at 4 and 8 weeks after surgery. The spines were harvested after the 8-week radiographs were obtained and evaluated using manual palpation, microCT analysis, and histological analysis. RESULTS Radiographs demonstrated equivalent bridging bone formation in all groups. No significant differences in fusion scores were seen in the standard-dose (mean 2.25) or high-dose (2.13) treatment groups relative to untreated control animals (1.78). Similarly, fusion rates did not differ significantly different between vancomycin-treated animals (100% for both groups) and control animals (92%). Quantification of new bone formation via microCT imaging revealed no significant between-groups differences in the volume of newly regenerated bone (control vs standard-dose vancomycin, p = 0.57; control vs high-dose vancomycin, p = 0.53). CONCLUSIONS This is the first in vivo study to specifically address the development of pseudarthrosis after intrawound application of vancomycin during fusion surgery. Our results demonstrate that vancomycin powder does not inhibit fusion rates at a dose that is the weight-percentage equivalent of what is routinely used by surgeons. Moreover, bone formation and fusion rates were not reduced even after administration of a vancomycin dose that is 10-fold higher than that which is typically administered clinically. Our findings suggest that if there is a critical threshold above which vancomycin inhibits bone healing, such a dose is out of the range which might be considered reasonable for clinical use.

Effect of recombinant human bone morphogenetic protein-2 on a novel lung cancer spine metastasis model in rodents.

Lung cancer is the second most prevalent cancer. Spinal metastases are found in 30-90% of patients with death attributed to cancer. Due to bony destruction caused by metastases, surgical intervention is often required to restore spinal alignment and stability. While some research suggests that BMP-2 may possess tumorigenic effects, other studies show possible inhibition of cancer growth. Thirty-six athymic rats underwent intraosseous injection of lung adenocarcinoma cells into the L5 vertebral body. Cells were pre-treated with vehicle control (Group A) or rhBMP-2 (Group B) prior to implantation. At 4 weeks post-implantation, in vivo bioluminescent imaging (BLI) was performed to confirm presence of tumor and quantify signal. Plain radiographs and microComputed Tomography (microCT) were employed to establish and quantitate osteolysis. Histological analysis characterized pathologic changes in the vertebral body. At 4 weeks post-implantation, BLI showed focal signal in the L5 vertebral body in 93% of Group A animals and 89% of Group B animals. Average tumor burden by BLI radiance was 7.43 × 10(3) p/s/cm(2) /sr (Group A) and 1.11 × 10(4) p/s/cm(2) /sr (Group B). Radiographs and microCT demonstrated osteolysis in 100% of animals showing focal BLI signal. MicroCT demonstrated significant bone loss in both groups compared to age-matched controls but no difference between study groups. Histological analysis confirmed tumor invasion in the L5 vertebral body. These findings provide a reliable in vivo model to study isolated spinal metastases from lung cancer. Statement of Clinical Significance: The data support the notion that exposure to rhBMP-2 does not promote the growth of A549 lung cancer spine lesions. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1274-1281, 2016.

Is potential malnutrition associated with septic failure and acute infection after revision total joint arthroplasty?

BACKGROUND: Although malnutrition has been hypothesized to increase the risk of periprosthetic joint infection (PJI), strong evidence linking the two is lacking. QUESTIONS/PURPOSES: The purposes of this study were to determine (1) if one or more laboratory values suggestive of malnutrition is independently associated with being revised for an infected joint arthroplasty as opposed to for an aseptic failure; (2) the relationship between laboratory parameters suggestive of malnutrition and obesity; and (3) if one or more laboratory parameters suggestive of malnutrition is independently associated with acute PJI complicating an aseptic revision procedure. METHODS: Between 2002 and 2010, one surgeon performed 600 revision total joint arthroplasties in 547 patients; during that time, nutritional parameters (including serum albumin, total lymphocyte count, and transferrin) were routinely obtained preoperatively; complete data sets were available on 454 patients (501 procedures [84%]). We compared the frequency of having one or more laboratory parameters suggestive of malnutrition between patients undergoing a revision for septic reasons and aseptic reasons as well as between obese and nonobese patients. The 375 aseptic revisions were then assessed for the incidence of acute postoperative infection (within 90 days, diagnosed with Musculoskeletal Infection Society criteria). Multivariate logistic regression modeling was used to evaluate factors independently associated with (1) a septic as opposed to an aseptic mode of failure; and (2) acute postoperative infection after an aseptic revision. RESULTS: Patients in 67 of 126 (53%) revisions for PJI had one or more laboratory parameters suggestive of malnutrition compared with 123 of 375 (33%) undergoing revision for a noninfectious etiology (odds ratio [OR], 2.3 [95% confidence interval, 1.5-3.5]; p<0.001). Patients who were of normal weight at the time of revision had the highest frequency of laboratory parameters suggestive of malnutrition (42 of 82 [51%]), although this was common in obese patients as well (76 of 238 [32%]) (p=0.002). Among the 375 aseptic revisions, 12 developed an acute postoperative infection (3%). The frequency of infection was nine of 123 in the group having one or more laboratory parameters suggestive of malnutrition and three of 252 in the group not having such laboratory parameters (7% versus 1%; p=0.003). Multivariate regression revealed that having laboratory parameters suggestive of malnutrition is independently associated with both chronic PJI (p=0.003; OR, 2.1) and an acute postoperative infection complicating an aseptic revision arthroplasty (p=0.02; OR, 5.9). CONCLUSIONS: Having one or more laboratory parameters suggestive of malnutrition is common among patients undergoing revision arthroplasty and is independently associated with both chronic septic failure and acute postoperative infection complicating a revision performed for a noninfectious etiology. Future studies should assess the impact of a standardized screening protocol with subsequent correction of abnormal laboratory parameters suggestive of malnutrition on the risk of PJI to determine a potential causal relationship between the two. LEVEL OF EVIDENCE: Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.