Joseph T. Moskal

The Effect of Tranexamic Acid on Blood Loss and Transfusion Rate in Primary Total Knee Arthroplasty

Allogeneic blood transfusions remain common in primary total knee arthroplasty. We reviewed our experience with 2269 consecutive primary total knee arthroplasties in 2069 patients over a 3.5 year period. In our cohort, 1838 received no TXA, 330 received TXA via IV infusion, and 130 had TXA applied topically. The need for blood transfusion, as well as hematocrit levels immediately after surgery in the recovery room and the day of discharge were recorded. Tranexamic acid infusion demonstrated a statistically significant decrease in blood transfusion (P=0.001), as did topical application of TXA (P=0.019). The transfusion rate without TXA was 6.5% (120/1839) but only 0.3% (1/330) with TXA infusion. There were no transfusions (0/130) with topical TXA. Statistical differences were also noted in both immediate post operative and day of discharge hematocrit levels in patients having TXA infusion while those values for patients with TXA irrigation failed to obtain statistical significance. No significant change in the rate of symptomatic deep venous thrombosis or pulmonary embolism was noted.

The effect of tranexamic acid on transfusion rate in primary total hip arthroplasty.

Total hip arthroplasty (THA) may produce blood loss requiring allogenic blood transfusion. Recently several authors have reported success decreasing their transfusion rate with tranexamic acid (TXA). We retrospectively reviewed our last 1595 primary THA in 1494 patients looking at whether the patients received TXA via IV infusion, topical application, or neither, and the need for a blood transfusion. Infusion of TXA acid produced a statistically significant difference in transfusion rate (p<0.001) while topical TXA failed to reach statistical significance (P=0.15). The transfusion rate without TXA was 19.86%, 4.39% with TXA infusion (odds ratio=5.36), and 12.86% (odds ratio=1.67) with topical TXA.

Improving the Accuracy of Acetabular Component Orientation: Avoiding Malpositioning

Many factors such as poor visualization, greater patient size, inaccuracies of mechanical guides, and changes in patient positioning during surgery can negatively impact acetabular component positioning1. Improper orientation contributes to an increased dislocation rate, limb-length discrepancy, component impingement, bearing surface wear, and revision surgery. Acetabular malpositioning also contributes to altered hip biomechanics, pelvic osteolysis, and acetabular component migration2-8. Despite the established definitions of acetabular safe zones, a recent analysis of United States Medicare total hip arthroplasty data revealed dislocation rates during the first six postoperative months to be 3.9% for primary arthroplasty and 14.4% for revision arthroplasty9. A recent report cited instability and dislocation as accounting for 22.5% of revision cases10. The use of larger femoral head sizes in primary total hip arthroplasty has increased dramatically in recent years with the introduction of alternative bearings and has reduced the short-term dislocation rate by almost one-half from 1998 to 2007 (from 4.21% to 2.14%)11. Dislocation rates have been lowered by increasing the femoral head-neck ratio, decreasing component impingement, increasing the range of hip motion until impingement, and increasing the jump distance when component impingement does occur12,13. Nevertheless, larger femoral heads are not a substitute for proper component placement and precise component orientation; inaccurate component positioning may be associated with alteration in soft-tissue tension and hip biomechanics leading to abnormal gait, trochanteric bursitis, and increased discomfort during walking. All total hip arthroplasty bearing couplings are intolerant of component malpositioning or variation in component positioning; specifically, they are intolerant of excessive lateral opening and anteversion—and implant survivorship and complications are directly related to component positioning8,14. Kurtz et al. forecast that the number of primary and revision hip arthroplasties will significantly increase over the …

Is ICD-9 Coding of Morbid Obesity Reliable in Patients Undergoing Total Knee Arthroplasty?

&NA; Morbid obesity is considered to have a stronger association with complications after total knee arthroplasty (TKA). Although the impact of obesity coding errors has been previously reported, the extent of coding inaccuracies with respect to morbid obesity is unclear. Therefore, the purpose of this study was to assess (1) the utility of coding in identifying morbid obesity and (2) the effects of morbid obesity on 90‐day complications after TKA when morbid obesity was defined by both body mass index (BMI) and International Classification of Diseases 9th edition (ICD‐9) coding. A total of 18,030 primary TKAs performed at a single institution from 2004 to 2014 were identified. Patients were defined as morbidly obese based on ICD‐9 codes or by BMI recorded in the electronic medical record (EMR). Patients were defined as obese (ICD‐9 codes 278.0, 278.00, 278.01, 278.03, 649.10‐14, 793.91, V85.30‐39, V85.41‐45, V85.54) or morbidly obese (278.01, V85.41‐45) by ICD‐9 codes. Patient EMRs were also reviewed to identify obese and morbidly obese patients (BMI cutoffs of 30 and 40 kg/m2, respectively). Complications between the cohorts were compared. Sensitivity and specificity were also calculated. Among the 2,880 surgeries performed in morbidly obese patients, a code for obesity was present in 1,618 (56.2%) surgeries, but only 57.9% (937) of these patients had a code specific for morbid obesity, with the rest having a code not specifying morbid obesity. The sensitivity and specificity of obesity coding were 34.5 and 96.0%, while that of morbid obesity were 32.5 and 96.7%, respectively (area under curve: 0.65 vs. 0.65, p = 0.214). A higher rate of complications was noted when patients were defined as morbidly obese by ICD‐9 as when defined by EMR‐reported BMI. Although morbidly obese patients are more likely to have a code for obesity compared with obese patients, these patients may not be correctly identified as morbidly obese due to a lack of specificity in the codes. These errors may lead to inadequate reimbursements, and may also overestimate the effect of morbid obesity on complications.

Operative Time, Length of Stay, Short-Term Readmission, and Complications after Hinged Primary Total Knee Arthroplasty: A Propensity Score Matched Analysis

&NA; Despite the wide utilization of total knee arthroplasty (TKA), it can be technically challenging to perform in patients who have concomitant bone loss, ligamentous laxity, or high‐grade deformity, whether in a revision situation or due to a primary pathology. Therefore, hinged knee prostheses have been developed to provide more stable fixation in these situations. The purpose of this study was to compare the short‐term peri‐ and postoperative outcomes of patients undergoing primary TKA with and without hinged prosthesis. Specifically, we compared (1) mean operative times, (2) lengths of stay (LOS), (3) 30‐day readmissions, and (4) complications. The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify hinged TKAs and 99 procedures were included. They were matched in a 1:3 ratio to primary TKAs without a hinged prosthesis using propensity score matching. Operative time, LOS, discharge disposition, 30‐day readmissions, and complications were compared. Adjusted odds ratios (OR) were also calculated. The operative time was significantly higher in hinged cohort compared with the nonhinged cohort (mean difference [MD] = 22 minutes; range, 10‐34 minutes, p < 0.001). There were no significant differences between hinged and nonhinged TKAs with respect to LOS (MD= 0.61 days, range, ‐0.07‐1.30 days, p = 0.080), discharge disposition (OR = 1.09, 95% confidence interval [CI], 0.66‐1.84), readmissions (OR = 2.67, 95% CI, 0.84‐8.24), and any complications (OR = 1.13, 95% CI, 0.55‐2.19). Not surprisingly, primary TKAs with hinged prostheses had increased operative times, but had similar LOS, discharge dispositions, and 30‐day rates of readmission and complications when compared with TKAs without a hinged prosthesis. One potential contributing factor to the increased operating time is that patients who receive a hinged implant tend to present with more severe deformities. It is reassuring to know that early outcomes were similar between both cohorts (although we await longer follow‐up studies), and that hinged implants can be considered in these difficult to treat patients.

Total knee arthroplasty in the face of a previous tuberculosis infection of the knee: what do we know in 2018?

ABSTRACT Introduction: TB of the knee is often associated with marked morbidity because of its late and non-specific presentation. The use of TKA (total knee arthroplasty) in the face of a previous tuberculous knee infection has been criticized with multiple controversies. Therefore, the purpose of this review is to assess: (1) clinical outcomes, (2) radiographic outcomes, and (3) complications of TKA in the face of a previous healed TB infection. Our analysis has demonstrated that previous TB infection of the knee joint does not preclude TKA if indicated and suggests placing patients who have ESR or CRP results out of normal range on pre-operative anti-TB prophylactic antibiotic for a minimum of 2 weeks. In case of local recurrence following TKA, antibiotic therapy alone can be an effective treatment option. Areas covered: We examined reported outcomes of performing TKA in patients with previous TB infection of the knee. Different strategies recommended by different authors to maximize the success of TKA in this situation are also discussed. Expert commentary: TKA has been proven to be effective in patients who are status post tuberculous arthritis when thoughtful patient selection and peri-operative planning is conducted. Tuberculosis continues to have a rising incidence and increasing spread of multi-drug resistant strains.

Early Instability with Mobile Bearing Total Knee Arthroplasty: A Series of Twenty-Five Cases

Between Dec. 1987 and Jan. 2002, twenty-five cases of clinical instability following mobile bearing total knee arthroplasty with meniscal bearings or rotating platforms presented for evaluation at our institution. These cases were retrospectively identified. All were performed at outside institutions by a variety of surgeons. All clinical examinations were performed by the authors. Nine cases were revised at our institution. All twenty-five cases had clinical evidence of severe coronal plane instability and pain. Eight cases had polyethylene dislocation or subluxation evident radiographically and clinically. Four cases had extensor mechanism dysfunction. Eighteen cases had symptoms immediately postoperatively. Twenty-three of the twenty-five cases had symptoms within two years postoperatively. Any potential long-term benefit of design innovations must be balanced with known problems leading to early failure. This paper is a review of a previously published manuscript by Dr.’s Moskal and Ridgeway [Ridgeway, S. R. and Moskal, J. T., “Early Instability with Mobile Bearing Total Knee Arthroplasty: A series of twenty-five cases,” J. Arthroplasty, Vol. 19, No. 6, 2004, pp. 686–693]. The current manuscript has been updated with additional discussion and references covered in his planned presentation.