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Richard S Laskin

Publications and source records attributed to Richard S Laskin.

14 recordsLinked to original sources
PubMed2004

Stiffness after total knee arthroplasty.

Limitation of motion after knee arthroplasty can be the result of a multiplicity of factors. Among these are malpositioning of the components, especially in the sagittal plane; oversizing at the patellofemoral or tibiofemoral joint spaces; retaining posterior osteophytes; and persisting with a tight posterior cruciate ligament. Postoperatively, problems with physical therapy likewise can cause limitation of both extension and flexion. Specific patient factors also may affect the range of motion after surgery. Although most patients achieve a postoperative flexion that is highly correlated to that which was present preoperatively, factors such as pain, obesity, and deformities of adjacent joints may limit such motion.

Arthroplasty, Replacement, Knee↗
PubMed2004

The use of a personal digital assistant in orthopaedic surgical practice.

The personal data assistant is a powerful tool enabling data acquisition, analysis, and scheduling. The Palm and Windows Pocket PC Operating Systems are available in various personal data assistants that combine bright screens, ease of use, and compactness. Data that are acquired can be imported into standardized spreadsheets for statistical analysis. Report generation using these data can simplify record keeping, facilitate later research, and decrease secretarial typing time. The use of a forms manager, such as Pendragon Forms, enables rapid creation of personal data assistant forms that interface with numerous computer database programs. We currently use theses programs for data acquisition when patients are seen in the office, in the operating room, and when returning for followup.

Computers, Handheld↗
PubMed2003

Instrumentation pitfalls: you just can't go on autopilot!

Instrumentation for total knee arthroplasty is crucial for proper positioning and orientation of the components. Instruments, however, must be used properly if the surgeon is to accomplish the goals. The entrance point for intramedullary guides for both the femur and tibia should not be arbitrarily chosen but picked after evaluation of the intersection of the anatomic axes of the respective bones with their articular surfaces. Saw blades must be held on cutting blocks, and the blocks themselves affixed to bones with sufficient pins to assure stability. If an extramedullary tibial alignment guide is chosen, its distal position should be in the center of the ankle plafond, not in the mid-malleolar point. In the lateral plane, it should parallel the shaft of the fibula. Femoral component rotation cannot always be judged from the posterior condylar tangent line. There may be difficulties of deformity with bone and cartilage loss, especially in valgus knees. Surgeons need to be mindful of the epicondylar axis and the midtrochlear of the anteroposterior axis of Whiteside.

Arthroplasty, Replacement, Knee↗
PubMed2003

An oxidized Zr ceramic surfaced femoral component for total knee arthroplasty.

A ceramic surfaced oxidized Zr femoral component was used in total knee replacedent. Prior mechanical testing had shown a decrease in adhesive and abrasive wear using this material as compared with CoCrMo suggesting its use in younger patients in whom long-term PE wear is a consideration. The alloy had no demonstrable Ni impurities and was applicable to patients with Ni or Co allergies. In a randomized prospective study comparing femoral components of the same design but fabricated either of cast CoCrMo or oxidized Zr, there was a more rapid return of flexion and regaining functional milestones in the oxidized Zr group. No adverse effects had been observed at the 2-year evaluation.

Arthroplasty, Replacement, Knee↗
PubMed2003

The spectrum of prosthesis design for primary total knee arthroplasty.

Many types of prostheses are currently used for total knee arthroplasty. Controversy exists, however, regarding which prostheses are the most appropriate for use by individual surgeons and specific patient groups. Six types of prostheses are currently being used in the United States for primary total knee arthroplasty: posterior cruciate ligament-retaining prostheses; posterior cruciate ligament-substituting prostheses; prostheses with ceramic components; mobile-bearing prostheses; nonmodular, compression-molded polyethylene prostheses; and medial-pivot prostheses. The historical and current result of using these different types of prostheses are discussed, and the indications, contraindications, and recommendations for each type are delineated.

Anterior Cruciate Ligament↗
PubMed2002

Ten steps to an easier revision total knee arthroplasty.

Revision total knee arthroplasty can be facilitated by proper preoperative planning, using an extensile incision, lysing of adhesions on the lateral gutter, exposing the medial and lateral aspects of the proximal tibia, and stabilizing the patellar tendon. If the patella cannot be everted safely, the surgeon should be prepared to do a rectus snip or tibial tubercle osteotomy. The components should be extracted axially after separation of the interfaces with a small sagittal saw or small osteotomes. The intramedullary canals of the femur and tibia should be used as references for the cutting blocks.

Arthroplasty, Replacement, Knee↗
PubMed2002

Joint line position restoration during revision total knee replacement.

Forty-five consecutive knee replacement revision operations done in 44 patients with a revision indication of instability were reviewed. In more than 1/2 of these patients, the prosthetic joint line was malpositioned proximally. At surgery, the joint line was restored through the use of distal femoral augments and balancing of the flexion and extension spaces. The fibular styloid and medial epicondylar reference points were used to determine proper position of the joint line. Scarring or laxity of the patellar tendon rendered the use of the Insall-Salvati ratio for determining joint line position inapplicable in these patients having revision knee replacement.

Arthroplasty, Replacement, Knee↗