Rodilla/Knee: Sin diferencias de riesgo de revisión con distintos polietilenos

Is There a Difference in Total Knee Arthroplasty Risk of Revision in Highly Crosslinked versus Conventional Polyethylene?

Paxton EW, Inacio MC, Kurtz S, Love R, Cafri G, Namba RS.

Clin Orthop Relat Res. 2015 Jan 8. [Epub ahead of print]

Abstract

BACKGROUND: 

Highly crosslinked polyethylene (HXLPE) was introduced to reduce wear and associated osteolysis in total knee arthroplasty (TKA). However, there is limited clinical evidence that HXLPE is more effective than conventional polyethylene (CPE) in TKA.

QUESTIONS/PURPOSES: 

(1) Do primary TKAs with HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than TKAs with CPE tibial inserts? (2) In NexGen TKA (Zimmer Inc, Warsaw, IN, USA) bearings, do HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than CPE tibial inserts? (3) In Press-Fit Condylar TKA (PFC or PFC Sigma; DePuy Inc, Warsaw, IN, USA), do HXLPE tibial inserts have a lower risk of revision (all-cause, aseptic, and septic) than procedures performed with CPE tibial inserts?

METHODS: 

The Kaiser Permanente Total Joint Replacement Registry was used to identify primary TKAs (N = 77,084) performed during the study period (April 2001 to December 2011) with cobalt-chromium alloy on CPE (CoCr-CPE) and CoCr-HXLPE bearings. The registry has 95% voluntary participation and less than 9% were loss to followup during the 10-year study period. A total of 60,841 (79%) had CoCr-CPE bearings, 11,048 (14%) had CoCr-HXLPE bearings, and 5195 (7%) were unknown. Specific knee implant designs (NexGen, Zimmer and PFC-Sigma, DePuy Inc) were also evaluated. These implants represented 41% (31,793) and 49% (37,457), respectively, of the 77,084 TKAs of known implant types registered during that period; implant selection was at the discretion of the attending surgeon. Descriptive statistics and marginal Cox regression models with propensity score adjustments were applied to compare risk of revision for CoCr-CPE versus CoCr-HXLPE TKA bearings.

RESULTS: 

At 5 years followup, cumulative incidence of revision for CoCr-CPE and CoCr-XLPE were 2.7% and 3.1%, respectively. Adjusted risks of all-cause (hazard ratio [HR], 1.05; 95% confidence interval [CI], 0.86-1.29; p = 0.620), aseptic (HR, 1.01; 95% CI, 0.77-1.32; p = 0.954), and septic revision (HR, 1.11; 95% CI, 0.81-1.51; p = 0.519) did not differ in patients with CoCr-XLPE bearings compared with CoCr-CPE. Within TKAs with NexGen components, the adjusted risks of all-cause (HR, 1.14; 95% CI, 0.86-1.51; p = 0.354), aseptic (HR, 1.14; 95% CI, 0.79-1.65; p = 0.493), and septic revision (HR, 1.14; 95% CI, 0.76-1.73; p = 518) were similar in patients with CoCr-XLPE compared with those with CoCr-CPE bearings. Finally, within the TKAs with PFC components, the adjusted risks of all-cause (HR, 0.80; 95% CI, 0.49-1.30; p = 0.369), aseptic (HR, 0.62; 95% CI, 0.62-1.14; p = 0.123), and septic revision (HR, 0.97; 95% CI, 0.51-1.85; p = 0.929) were also similar in patients with CoCr-XLPE compared with those with CoCr-CPE bearings.

CONCLUSIONS: 

In this large study, we did not find differences in risk of revision for CoCr-HXLPE compared with CoCr-CPE bearings at 5 years followup. In selecting HXLPE in TKA, clinicians should consider the increased cost and lack of available evidence of performance for greater than 10 years followup. Future studies are necessary to evaluate longitudinal outcomes of CoCr-HXLPE versus conventional TKA bearings.

LEVEL OF EVIDENCE: 

Level III, therapeutic study. 

Rodilla-cadera/Knee-Hip: Postoperatorio más gravoso a mayor ASA

The Association of ASA Class on Total Knee and Total Hip Arthroplasty Readmission Rates in an Academic Hospital
Jordan F. Schaeffer, Daniel J. Scott, Jonathan A. Godin, David E. Attarian, Samuel S. Wellman, Richard C. Mather III
The Journal of Arthroplasty
Published Online: December 16, 2014
DOI: http://dx.doi.org/10.1016/j.arth.2014.12.01

Abstract

Total hip and knee arthroplasty are two of the most successful procedures in orthopaedics. However, with the increasing demand, estimated future costs for these procedures are enormous. Recent data suggests that post-discharge care may account for up to 35% of total episode payments. Yet, little is known about targets that can help improve quality and reduce cost. This retrospective study shows that an ASA score of ≥3 is associated with a 2.9 times (p = 0.0082) greater risk of re-admission in total joint arthroplasty patients. The current literature corroborates this finding by demonstrating an increase risk of post-operative complications in patients with an ASA of ≥3. Therefore, the ASA score is a potential target for interventions designed to increase quality and lower cost in arthroplasty patients.

Rodilla/Knee/Knie: Cemento el justo

Can Cementing Technique Reduce the Cost of a Primary Total Knee Arthroplasty?

Maheshwari A, Argawal M, Naziri Q, Pivec R, Mont MA, Rasquinha VJ

J Knee Surg 2014 Apr 21.

Abstract

Studies on cost containment of total knee arthroplasty (TKA) have generated substantial interest over the past decade. Although multiple studies have evaluated the various intraoperative methods to control cost, no prior study has evaluated the economic impact and the clinical outcome based on amount of bone cement needed for a primary TKA. At a minimum of 3 years follow-up, we observed no difference in implant survivorship or Knee Society scores, but did observe substantial cost savings when one versus two packets of bone cement were used in combination with a hand mixing technique. By eliminating several extra cement mixing products, we achieved an approximately $1,000 cost saving per case with no difference in clinical outcomes at midterm follow-up.