Increased benthic algal primary production in response to the invasive zebra mussel (Dreissena polymorpha) in a productive ecosystem, Oneida Lake, New York.

Increased water clarity associated with zebra mussel (Dreissena polymorpha) populations may favor benthic algal primary production in freshwater systems previously dominated by pelagic phytoplankton production. While zebra mussel-mediated water clarity effects on benthic primary production have been implicated in published reports, few production estimates are available. This study estimates benthic primary production in Oneida Lake, NY before and after zebra mussel invasion (1992), using measured photosynthetic parameters (, alpha(B) and beta) from sampled benthic algal communities.

A third-generation, posterior-stabilized knee prosthesis: early results after follow-up of 2 to 6 years.

Two hundred seventy-nine primary total knee arthroplasties were performed with a modular, cemented, third-generation, posterior-stabilized prosthesis. At mean follow-up of 48 months (range, 24-72 months), the outcomes of 238 knees (85%) were evaluated with the Knee Society's Knee and Functional Scoring Systems and Roentgenographic Scoring System. The mean preoperative Knee Society Knee Score was 48 points compared with 96 points at latest follow-up.

The influence of femoral component design in the elimination of patellar clunk in posterior-stabilized total knee arthroplasty.

Patellar clunk occurs after posterior-stabilized total knee arthroplasty and is believed to be a design-related complication. This study was undertaken to define the incidence of patellar clunk with an optimized third-generation, posterior-stabilized prosthesis. One hundred ninety three patients with 238 knees were evaluated at a minimum of 2 years after primary total knee arthroplasty with a cemented, NexGen Legacy Posterior-Stabilized prosthesis (Zimmer, Warsaw, Ind).