Center for Biomedical Research Excellence Grant (P20-RR16458)

Women in Science and Engineering (WISE)
Program Director Thomas S. Buchanan, PhD

Project 5: Knee Stiffness, Proprioception & Instability affect Knee Control in OA

Katherine Rudolph, PT, PhD
Principal Investigator
Associate Professor, Department of Physical Therapy
Director, Interdisciplinary Program in Biomechanics & Movement Science

301 McKinly Lab
Newark, DE 19716
302-831-4235

krudo@udel.edu

Dr. Rudolph's Home Page

Investigators:        

Charles (Buz) Swanik, PhD

Department of Health and Exercise Science
Stiffness and Proprioception tests

Kurt Manal, PhD

Department of Mechanical Engineering
Musculoskeletal modeling

Michael Axe, MD

Orthopaedic Surgeon

First State Orthopaedics


Purpose

The long term goal of the work in our lab is to understand the neuromuscular control strategies used by people with knee OA in order to develop innovative treatment programs that will improve function and slow the the disease progression.

The purpose of present study explore the influence of strength, proprioception, and quadriceps stiffness on knee stabilization strategies in people with MKOA what influence stabilization strategies have on joint load. investigate if people with knee OA who experience buckling in the knee (“instability”) are able to adapt their neuromuscular control strategies similar to healthy individuals.

Research Assistant Duties

Research assistants are a vital part of the work in this lab. The work they perform helps to make data collections run smoothly and enhances the experience of the subjects who volunteer their time to take part in our research. The tests that we perform are outlined in detail and in lay language in our Consent to Participate in Research form, approved by the University of Delaware Human Subjects Review Board. Some of the duties of research assistants involved in the tests are listed below.

Research Tests Performed:

1. X-rays (~30 minutes)

Four x-rays are taken by an experienced radiographer at the offices of First State Orthopaedics located at 4745 Ogletown-Stanton Road, Newark, DE.

Under the supervision of a researcher or graduate student, research assistants greet subjects, direct them to the correct waiting areas, help the researcher record data etc.

2. Strength testing and functional assessment (1.5 hours):

Strength: We measure the amount of torque that the quadriceps muscles produce (muscles in the front of the thigh that straighten the knee) in the Muscle Performance Laboratory in the Physical Therapy Department at the University of Delaware, Room 325 McKinly Laboratory, Newark, DE 19716.

Function: We also test how well the subjects function in their daily lives by having subject fill out questionnaires inclunding the Knee Injury Osteoarthritis Outcome Scale, the Knee Outcome Survey and they perform 2 timed tests, a stair climbing test and one involving rising from a chair.

Under the supervision of a researcher or graduate student, research assistants help to greet subjects, hand out paperwork, record data and enter data into research data bases.

3. Motion Analysis Testing (up to 3.5 hours):

We measure how the joints move and when muscles turn on and off during walking and standing in the Motion Analysis Laboratory in the Physical Therapy Department at the University of Delaware, Room 326 McKinly Laboratory, Newark DE 19716. Four-inch wide elastic bands are wrapped around the thighs, calves, and hips to which small balls are attached. Additional balls will be taped to the hips, knees, ankles and sneakers with adhesive skin tape.

Small sensors are placed on the skin over the muscles in the front and back of the thigh and back of the calf with adhesive skin tape. Cables from the sensors attach to a small box that will be placed in a backpack that is worn during the tests. The box helps send information about the muscle activity to a computer. The movements of the joints and when the muscles turn on and off are recorded on a computer and later processed.

Under the supervision of a researcher or graduate student, research assistants prepare the equipment for the session, greet subjects, lay out equipment, hand markers or sensors to the person putting them on the subject, record information related to the placement of sensors, direct the subjects to the correct starting positions etc.

4. Stiffness and Proprioception Testing

The term "proprioception" refers to the ability to sense your body is space. To test the ability to detect knee motion and joint position sense subjects are seated in a chair with the knee of the tested leg positioned at two different starting angles. The foot and lower leg are placed in a splint (shown in the figure to the right) and then attached to a motor that will bend and straighten the knee. Subjects are blindfolded for a short period of time and wear a head-set to eliminate cues from sights and sounds. The knee is moved at different speeds in a straightening and bending direction and the subject indicates when he or she detects the motion or when the knee has reached a particular position.

Stiffness is the rate of torque development and it is tested by rapidly bending or straightening the knee and measuring the torque developed by the passive elastic structures of the joint and muscles, as well as the reflexive activation of the muscles when they are stretched quickly.

Under the supervision of a researcher or graduate student, research assistants help to greet subjects, hand out paperwork, record data and enter data into research data bases.

The duties of a research assistant vary widely depending on the project they work on and what part of the project is active on a particular day.  RA duties might include helping with data collections, computer data processing, filing, doing laundry, running errands to buy supplies, cleaning and organizing lab equipment.  Research assistants are an important part of our lab thus it is vital that the RA be self-motivated, dependable and have good attention to detail.