Parthiv A. Rathod

Does Fluoroscopy With Anterior Hip Arthoplasty Decrease Acetabular Cup Variability Compared With a Nonguided Posterior Approach

BackgroundThe direct anterior approach for THA offers some advantages, but is associated with a significant learning curve. Some of the technical difficulties can be addressed by the use of intraoperative fluoroscopy which may improve the accuracy of acetabular component placement.Questions/purposesThe purposes of this study were to determine if (1) there is decreased variability of acetabular cup inclination and anteversion with the direct anterior approach using fluoroscopic guidance as compared with the posterior approach THA without radiographic guidance; (2) if there is a learning curve associated with achieving accuracy with the direct anterior approach THA. We also wanted (3) to assess the frequency of complications including dislocation with the anterior approach, which initially had a learning curve, and the posterior approach.MethodsThis retrospective, comparative study of 825 THAs (372 posterior THAs without fluoroscopic guidance and 453 direct anterior THAs, performed by one surgeon, focused on a radiographic analysis to determine cup inclination and anteversion on standardized pelvic radiographs using specialized software. The first 100 direct anterior THAs performed while transitioning from the posterior approach to the direct anterior approach were included in the learning curve group. During this learning curve period, the direct anterior approach was used for all patients except those with conversion of previously fixed intertrochanteric or femoral neck fractures to THAs, gluteus medius tears, and obese patients with an immobile abdominal pannus (100 of 127 THAs). Variability of the acetabular component was compared among the posterior group, learning curve group, and direct anterior group.ResultsVariances for cup inclination and anteversion were significantly lower in the direct anterior group (19 and 16 respectively, p < 0.01) as compared with the posterior group (50 and 79 respectively).Target inclination and anteversion were achieved better in the direct anterior group (98% and 97% respectively) as compared with the posterior group (86% and 77% respectively) (p < 0.01, OR for inclination = 9.1, 95% CI, 3.5 to 23.4; OR for anteversion = 8, 95% CI, 4 to 16). In the learning curve group, target anteversion achieved (91% of cases) was marginally lower than that of the direct anterior group (p = 0.03; OR = 2.9, 95% CI, 1.1 to 7.3) and target inclination (95%) was similar (p = 0.13). There was one posterior dislocation in the posterior group, two anterior dislocations in the learning curve group, and none in the direct anterior group.ConclusionsUse of fluoroscopy with the patient in the supine position during direct anterior THA enables intraoperative assessment of cup orientation resulting in decreased variability of acetabular cup anteversion. However, there is a learning curve associated with achieving this accuracy. We could not discern whether this difference was the result of the approach or the use of fluoroscopy in the direct anterior group.Level of EvidenceLevel III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Management of Modifiable Risk Factors Prior to Primary Hip and Knee Arthroplasty: A Readmission Risk Assessment Tool.

BACKGROUND Preoperative risk stratification and optimization of preoperative care may be helpful in reducing readmission rates after primary total joint arthroplasty. Assessment of the predictive value of individual modifiable risk factors without a tool to assess cumulative risk may not provide proper risk stratification of patients with regard to potential readmissions. As part of a Perioperative Orthopaedic Surgical Home model, we developed a scoring system, the Readmission Risk Assessment Tool (RRAT), which allows for risk stratification in patients undergoing elective primary total joint arthroplasty at our institution. The purpose of this study was to analyze the relationship between the RRAT score and readmission after primary hip or knee arthroplasty. METHODS The RRAT, which is scored incrementally on the basis of the number and severity of modifiable comorbidities, was used to generate readmission scores for a cohort of 207 readmitted patients and two cohorts (one random and one age-matched) of 234 non-readmitted patients each. Regression analysis was performed to assess the strength of association of individual risk factors and the RRAT score with readmissions. We also calculated the odds and odds ratio (OR) at each RRAT score level to identify patients with relatively higher risk of readmission. RESULTS There were 207 (2.08%) readmissions among 9930 patients over a six-year period (2008 through 2013). Surgical site infection was the most common cause of readmission (ninety-three cases, 45%). The median RRAT scores were 3 (IQR [interquartile range], 1 to 4) and 1 (IQR, 0 to 2) for readmitted and non-readmitted groups, respectively. An RRAT score of ≥3 was significantly associated with higher odds of readmission. CONCLUSIONS Population health management, cost-effective care, and optimization of outcomes to maximize value are the new maxims for health-care delivery in the United States. We found that the RRAT score had a significant association with readmission after joint arthroplasty and could potentially be a clinically useful tool for risk mitigation.

Reducing Blood Loss in Bilateral Total Knee Arthroplasty with Patient-Specific Instrumentation

Patient-specific instrumentation (PSI) in total knee arthroplasty (TKA) has been introduced to obtain consistent alignment, prevent instrumentation of the medullary canal and improve operating room efficiency. This article compares simultaneous bilateral TKA performed with and without the use of PSI in terms of surgical time; blood loss and transfusion requirements; length-of-stay, early thromboembolic events and complication rates. There was a trend to reduced total blood loss (as measured by drop in hemoglobin values) and lower transfusion rate after surgery. Further research in the form of high quality randomized trials and cost-benefit analyses may help in further consolidation of these findings.

Does Tourniquet Time in Primary Total Knee Arthroplasty Influence Clinical Recovery

There are limited data on the influence of a reduced tourniquet time strategy on the clinical outcome of primary total knee arthroplasty (TKA). The aim of our study was to prospectively compare clinical recovery in two groups of patients undergoing TKA based on differences in tourniquet strategy at the same institution. Group A (40 patients) consisted of TKAs performed by a surgeon using tourniquet from incision to arthrotomy closure, and group B (40 patients) consisted of TKAs performed by another surgeon using tourniquet only during cementation. The surgical technique, implants, perioperative management, and patient demographics were similar between groups. Average tourniquet time was significantly higher in group A (71.7 minutes) as compared with group B (36.8 minutes). The maximum hemoglobin (Hb)/hematocrit (Hct) drop was statistically higher in group B (Hb drop = 3.5 ± 0.9 g/dL; Hct drop = 11 ± 3) as compared with group A (Hb drop = 2.9 ± 0.9 g/dL; Hct drop = 9 ± 2; Hb drop p = 0.01; Hct drop p = 0.002). There were no significant differences in visual analogue scale pain scores, narcotic consumption, ability to straight leg raise during hospital stay, range of motion (ROM) at discharge, as well as isometric quadriceps strength, ROM, Short Form 36 scores, Knee Society scores at 6 weeks, 3 months, and 1 year follow-up with a similar multimodal pain management protocol. Radiographic analysis revealed no differences in cement penetration around the tibial component in any zone. Four patients developed pulmonary embolism (three in group A, one in group B) and five patients underwent manipulation under anesthesia for stiffness (four in group A, one in group B). Thus, the use of a tourniquet only during cementing in TKA increases the hemoglobin drop and does not significantly influence pain or clinical recovery with available numbers, but was associated with a lower incidence of early complications. It is a learned surgical skill which significantly reduces tourniquet time and achieves a similar quality of cementing.

CORR Insights®: Premature Therapeutic Antimicrobial Treatments Can Compromise the Diagnosis of Late Periprosthetic Joint Infection

L acking definitive standards, the Musculoskeletal Infection Society (MSIS) created a definition for the diagnosis of periprosthetic joint infection (PJI), which was subsequently modified during the International Consensus meeting on PJI in 2013 [4]. The diagnostic criteria are based on both clinical and laboratory findings, and are considered more helpful than any single test might be in terms of reaching the diagnosis of PJI. However, the diagnostic picture may be confounded in cases when patients are on antibiotic therapy, which previous research has shown to be a risk factor for culture-negative PJI [3]. The recommendations by the American Academy of Orthopaedic Surgeons (AAOS) in their clinical practice guidelines discourage the use of antimicrobial treatments in patients with suspected PJI until after aspiration samples for intraoperative cultures are obtained. The AAOS also recommends withholding antibiotics for at least 2 weeks before intraarticular sample collection for culture if antibiotics have already been given [2]. However, in spite of these guidelines, some patients present for evaluation of suspected PJI having already been exposed to antibiotics. Unfortunately, we have no data to guide our interpretation of laboratory parameters such as serologic results and synovial fluid analysis in patients who had antibiotics prior to completion of a thorough workup for PJI. In the current study, Shahi and colleagues retrospectively evaluated the prospectively maintained PJI databases of three institutions and identified patients with late PJI (as per MSIS criteria) after TKA during a 12-year period. A total of 161 patients out of 1100 infected patients fit their criteria with 53 patients (33%) having received antibiotics before aspiration. The median erythrocyte sedimentation rate, C-reactive protein, synovial white blood cell count, and synovial polymorphonuclear neutrophil percentage This CORR Insights is a commentary on the article ‘‘Premature Therapeutic Antimicrobial Treatments Can Compromise the Diagnosis of Late Periprosthetic Joint Infection’’ by Shahi and colleagues available at: DOI: 10.1007/s11999-015-4142-z. The author certifies that he, or any member of his immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/ licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or the Association of Bone and Joint Surgeons. This CORR Insights comment refers to the article available at DOI: 10.1007/s11999-0154142-z. P. A. Rathod MD (&) Woodhull Hospital/NYU Hospital for Joint Diseases, 760 Broadway, 9th Floor, Brooklyn, New York, NY 11206, USA e-mail: drparthivrathod@gmail.com CORR Insights Published online: 6 March 2015 The Association of Bone and Joint Surgeons1 2015

Obesity: The Modifiable Risk Factor in Total Joint Arthroplasty

Obesity is an epidemic in the health care system. Obesity poses several challenges and raises unique issues for the arthroplasty surgeon. Obese patients are at higher risk for infection and dislocation. Additionally, obese patients have poorer implant survivorship and functional scores postoperatively. Obesity is a modifiable risk factor and weight loss preoperatively should be strongly considered. Obese patients must be counseled so that they have realistic expectations after total joint arthroplasty.

RE-REVISION TOTAL HIP ARTHROPLASTY: EPIDEMIOLOGY AND FACTORS ASSOCIATED WITH OUTCOMES

Introduction The epidemiology of re-revision total hip arthroplasty (THA) is not yet well-understood. We aim to investigate the epidemiology and risk-factors that are associated with re-revision THA. Methods 288 revision THA were analyzed between 1/2012 and 12/2013. Patients who underwent two or greater revision THA were included. Hips with first-revision due to periprosthetic joint infection (PJI) were excluded. Failure was defined as reoperation. Results 51 re-revision patients were available. Mean age was 59.6 (±14.2 years), 32 (67%) females, average BMI of 28.8 (±5.4), and median ASA 2 (23; 55%). The most common re-revision indications were acetabular component loosening (15; 29%), PJI (13; 25%) and instability (9; 18%). The most common indications for first revision in the re-revision population were acetabular component loosening (11; 27%), polyethylene wear (8; 19%) and instability (8; 19%). There was an increased risk of re-revision failure if the re-revision involved exchanging only the head and polyethylene liner (RR = 1.792; p = 0.017), instability was the first-revision indication (RR = 3.000; p < 0.001), and instability was the re-revision indication (RR = 1.867; p = 0.038). If isolated femoral component revision was indicated during the re-revision, there was a decreased risk of failure (RR = 0.268, p = 0.046). 1-year re-revision survival was 54% (23/43). Discussion Acetabular component loosening, instability, and PJI were the most common indications for re-revision. Revision due to instability is a recurrent problem that leads to re-revision failure. There was a higher infection rate in the re-revision population compared to published revision PJI. A better understanding of the indications and patient factors that are associated with re-revision failures can help align surgeon and patient expectations in this challenging population.

CORR Insights®: Similar Clinical Outcomes for THAs With and Without Prior Periacetabular Osteotomy

This CORR Insights® is a commentary on the article “Similar Clinical Outcomes for THAs With and Without Prior Periacetabular Osteotomy” by Amanatullah and colleagues available at: DOI: 10.1007/s11999-014-4026-7. The author certifies that he, or any member of his immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research ® editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR ® or the Association of Bone and Joint Surgeons®. This CORR Insights® comment refers to the article available at DOI: 10.1007/s11999-014-4026-7.