Modern Total Knee Arthroplasty Bearing Designs and the Role of the Posterior Cruciate Ligament

The role of the posterior cruciate ligament (PCL) in total knee arthroplasty (TKA) surgery continues to be a source of debate among the adult reconstruction community. In native knee flexion, the PCL is comprised of an anterolateral and posteromedial bundle that work together to limit posterior tibial translation and allow adequate femoral rollback for deep flexion. In the arthritic knee, the PCL can often become dysfunctional and attenuated, which led to the development of posterior stabilized (PS) TKA bearing options. PS TKAs implement a cam-post construct to functionally replace a resected PCL. While PS designs may facilitate balancing knees with significant deformity, they are associated with complications such as postfracture, increased wear, and patellar clunk/crepitus. In recent years, newer designs have been popularized with greater degrees of congruency and incorporation of medial and lateral pivoting to better recreate native knee kinematics. The American Joint Registry has confirmed the recent predilection for ultra-congruent and cruciate-retaining TKA inserts over PS TKAs during the last decade. Studies have failed to identify an overall clinical superiority between the cruciate substituting and sacrificing designs. The literature has also failed to identify clinical consequences from PCL resection with modern, more conforming TKA designs. In this article, we review modern PCL sacrificing designs and discuss the impact of each on the kinematics after TKA. We also will delineate the role of the PCL in modern TKA in the hopes to better understand the recent surge in sacrificing but not substituting knee implants

Wound Complications in Joint Arthroplasty: Comparing Traditional and Modern Methods of Skin Closure

abstract Full article available online at Healio.com/Orthopedics. Search: 20120426-16 Various methods of skin closure exist in joint replacement surgery. Although subcuticular skin closure techniques offer an aesthetic advantage over conventional skin stapling, no measurable differences have been reported. Furthermore, newer barbed sutures, such as the V-Loc absorbable suture (Covidien, Mansfield, Massachusetts), theoretically distribute tension evenly through the wound and help decrease knotrelated complications. The purpose of this study was to evaluate whether wound complication rates were (1) lower in V-Loc closure cases as theoretically suggested, (2) lower for subcuticular closure vs staples, and (3) significantly different for knee and hip joint reconstruction. A retrospective chart review was conducted of 278 consecutive cases of primary joint reconstruction performed by a single surgeon (L.P.). The study group comprised 106 men and 161 women. Average patient age at surgery was 63 years (range, 18-92 years), and average body mass index of the cohort was 33.7 kg/m 2 (range, 25-51 kg/ m 2 ). Skin was closed via staple gun or subcuticular stitch (3-0 Biosyn [Covidien] vs V-Loc). Seven (3.9%) wound complications occurred in 181 cases closed with staples. Four (7.8%) wound complications occurred in 51 cases closed via subcuticular Biosyn suture. Six (13.0%) wound complications occurred in 46 cases closed with V-Loc suture. The staple group had a lower rate of complications when compared with the suture group as a whole (P5.033) and when compared specifically with the V-Loc suture group (P5.017). Drs Patel (Ronak) and Puri, Messrs Cayo and Patel (Arpan) Medicine, Northwestern University, 401 E Ontario St, Unit #1707, Chicago, IL 60611 ([email protected]). doi: 10.3928/01477447-20120426-16 Wound e64