Memorial Bone & Joint Research Foundation
Memorial Bone & Joint Research Foundation

Clinical Research Definitions

General research definitions

  • Clinical Research
    Clinical research is research that either directly involves individual people or uses material of human origin, such as observed behavior, answers to questions, or tissue samples obtained through direct contact with a particular living person that volunteers and agrees to participate in a research.

  • Clinical Trial
    Clinical trials are clinical research studies to determine whether biomedical or behavioral interventions are safe and effective.

  • Registry
    Is general collection of data on individual who have had a certain disease to follow up and evaluation of response to therapy.

  • Joint Registry
    Our joint registry consists of general data collection of patients who have undergone joint replacement surgery of the knee and/ or hip. The purpose of the joint registry at Memorial Bone & Joint Research Foundation is to improve clinical outcomes of patients with joint diseases. Data collected includes implant success rate, implant failure rate, anterior versus posterior surgical approach, revision and length of hospital stay.

  • IDE Study
    An Investigational Device Exemption (IDE) allows the investigational device to be used in a clinical study in order to collect safety and effectiveness data required to support a Premarket Approval (PMA) application or a Premarket Notification submission to the Food and Drug Administration (FDA).

  • Post Marketing Study
    As a requirement for approval or continued marketing of some medicine or device, the FDA may require additional information in the form of post marketing commitments (PMCs). These commitments are agreed to by a company with the FDA, and are used to gather additional information about a medicine or device's safety, efficacy, or optimal use. These agreements can be reached either before or after the FDA has granted approval to a company to market a medicine or device.

Knee Registry

  • Total Knee Replacement (TKA)

    Total knee replacement is the most common surgical knee intervention performed. Total knee replacement surgery is considered for patients whose knee joints have been damaged by either progressive arthritis, trauma, or other rare destructive diseases of the joint. The most common reason for knee replacement in the United States is severe osteoarthritis in all three compartments of the knee. Regardless of the cause of the damage to the joint, the resulting progressively increasing pain and stiffness and decreasing daily function lead the patient to consider total knee replacement.

    In total knee replacement, all 3 compartments of the knee are replaced. The natural joint is removed and replaced with an artificial metal and plastic component expected to last for 10 - 15 years. During a total knee replacement, the end of the femur bone is removed and replaced with a metal shell. The end of the lower leg bone (tibia) is also removed and replaced with a channeled plastic piece with a metal stem. Depending on the condition of the kneecap portion of the knee joint, a plastic "button" may also be added under the kneecap surface.

    The posterior cruciate ligament is a tissue that normally stabilizes each side of the knee joint so that the lower leg cannot slide backward in relation to the thigh bone. In total knee replacement surgery, this ligament is either retained, sacrificed, or substituted by a polyethylene post. Each of these various designs of total knee replacement has its benefits and risks.

  • Partial Knee Replacement - Unicomparmental Knee Arthroplasty (UKA)
    Unicomparmental Knee Arthroplasty, also called partial knee replacement, is an option for some patients. The knee is divided into three compartments - the medial compartment (inside part of knee), lateral compartment (outside part of knee), and patellofemoral compartment (the joint between the knee cap and the thigh bone). Most patients with arthritis severe enough to consider to knee replacement have significant wear in two or more of the above compartments and are best treated with total knee replacement. Total knee replacement is not optimal for patients with early to mid-stage osteoarthritis in one compartment of the knee. A minority of patients have arthritis confined primarily to one compartment, usually the medial, and may be candidates for unicomparmental knee replacement. With partial knee replacement only the diseased portion of the knee is removed, leaving the healthy bone and surrounding tissues untouched. The advantages of unicomparmental knee replacement compared to total knee replacement include a smaller incision, smaller scar, easier post-op rehabilitation, easier revision, if necessary, shorter hospital stay, less blood loss, and a lower risk of infection, stiffness and/or blood clots. Protected weight bearing on crutches or a walker is required until the quadriceps muscle has healed and recovered its strength. Post operative hospitalization varies from one day to three days on average depending on the health status of the patient and the amount of support available outside the hospital setting. Usually full range of motion is recovered over the first two to four weeks after surgery. At 4 weeks patients have usually progressed to full weight bearing with cane. Complete recovery from the operation involving return to full normal function may take 6 weeks to three months.

Hip Registry

  • Total Hip Replacement(THR)
    The total hip replacement is a surgical procedure whereby the diseased cartilage and bone of the hip joint is surgically replaced with artificial materials. The normal hip joint is a ball and socket joint. The socket is a "cup-shaped" bone of the pelvis called the acetabulum. The ball is the head of the thigh bone (femur). Total hip joint replacement involves surgical removal of the diseased ball and socket, replacing them with a metal ball and stem which is inserted into the femur bone, and an artificial titanium socket with a plastic liner. The metallic artificial ball and stem are referred to as the "prosthesis." Upon inserting the prosthesis into the central core of the femur, it is occasionally fixed with bony cement called methylmethacrylate. Alternatively, a "cementless" prosthesis is used which has microscopic pores that allow bony ingrowth from the normal femur into the prosthesis stem. This "cementless" hip is felt to have a longer duration and is considered especially for younger patients. Total hip replacements are performed most commonly because of progressively severe arthritis in the hip joint. The most common type of arthritis leading to total hip replacement is degenerative arthritis (osteoarthritis) of the hip joint. This type of arthritis is generally seen with aging, congenital abnormality of the hip joint, or prior trauma to the hip joint. Other conditions leading to total hip replacement include bony fractures of the hip joint, rheumatoid arthritis, and avascular necrosis of the hip bone. Hip bone necrosis can be caused by fracture of the hip, drugs (such as alcohol or steroids), diseases (such as systemic lupus erythematosus), and other conditions (such as kidney transplantation).

  • Direct Anterior Approach Total Hip Replacement
    The direct anterior approach for total hip replacement (THR) is one of the minimally invasive techniques used in hip replacement surgery. Continuing orthopedic experience suggests that this procedure may offer several advantages over the more traditional surgical approaches to hip replacement. Traditional hip replacement techniques involve operating from the side (lateral) or the back (posterior) of the hip, which requires a significant disturbance of the joint and connecting tissues and an incision approximately 8-12 inches long. In comparison, the direct anterior approach total hip replacement (THR) requires an incision that is only 3-4 inches in length and is located at the front of the hip. In this position, the surgeon does not need to detach any of the muscles or tendons. This may allow for a more natural return to normal function and activity. The smaller incision and reduced disruption indicate that patients may also have a shorter recovery time and less scaring. With this approach and the minimization of the tissue damage, there may also be less blood loss, less time in surgery and reduced post-operative pain. Some physicians use a special operating room table to help achieve an optimized surgical position for the patient.

  • FAI release
    If the affected hip does not show too much cartilage damage, reshaping of the abnormal femoral head and the abnormal edge of a too-deep socket (impingement release) can be performed with excellent results. The goal of this procedure is to eliminate the impingement, thus relieving symptoms and preventing or slowing the progression of osteoarthritis.

  • Femoro-Acetabular Impingement (FAI)
    Femoro-Acetabular Impingement (FAI) is a mechanical disorder of the hip causing stiffness, pain, and can lead to arthritis. FAI is condition where the gliding motion of hip is disturbed. Impingement occurs if there is a block or restriction to the normal hip motion. This can happen if the head of the femur is not entirely round, in which case there is jamming (cam impingement) when the abnormal part of the head is squeezed into the socket as the hip is bent. A second type of impingement (pincer impingement) occurs if the front edge of the acetabulum (socket) is too prominent. This allows the femur to bump into the rim of the acetabulum during normal hip movement. FAI may begin at birth (congenital). It may also develop during growth (acquired). It is likely caused by a combination of one's genetic and environmental factors.

  • Hip Resurfacing
    Hip resurfacing provides an alternative to primary total hip arthroplasty for younger and more active patients having osteoarthritis of the hip joint. The potential advantages of hip resurfacing include less bone removal (bone preservation), less chance of hip dislocations due to a relatively larger femoral head size, and possible easier revision surgery for a subsequent total hip replacement device because more bone stock is available to work with. Patient suitability for hip resurfacing is determined by the patient's anatomy and the doctor. Hip resurfacing is intended for younger patients, who are not morbidly obese, are clinically qualified for a hip replacement, have been diagnosed with non inflammatory degenerative joint disease, do not have an infection, and are not allergic to the metals used in the implant. Hip resurfacing should not be used on patients who have severe bone loss in their femoral head, those with large femoral neck cysts present (typically found at surgery), or patients who have poor bone stock in the acetabulum. During the procedure, the surgeon will remove a few centimeters of bone around the femoral head, shaping it to fit tightly inside the femoral head implant. The surgeon will also prepare the acetabulum for the metal cup that will form the socket joint. While the resurfacing component slides over the top of the femoral head like a tooth cap, the acetabular component is pressed into place much like a total hip replacement would be.

Sponsored Research studies

  • Uniglide Mobile Bearing IDE study
    The device is called Uniglide Mobile Bearing Unicondylar Knee System. Unicondylar means that the knee device replzaces only a part of your knee joint or is sometimes referred to as a "half" of a knee replacement. It is intended for use in subjects with osteoarthritis of the inner side of the knee.

    Uniglide Mobile Bearing Unicodylar Knee System has 3 parts. A component made of metal (cobalt chrome) that fits over the end of your femur (thigh bone in your upper leg), a component made of metal (cobalt chrome) that sits on top of your tibia (large bone in your lower leg) and polyethylene (hard plastic) insert that sits between the two metal parts that moves as your knee bends and extends with activity.

    This study is designed to compare the Uniglide Mobile Bearing Uniglide Knee System to the Uniglide Fixed Bearing Uniglide Knee System, which is currently approved by the FDA for marketing in the U.S. The difference between the two knee systems is that the Mobile Bearing Knee System is designed to provide for more movement in the knee as you do your normal activities.

    The purpose of the study is to collect information on the safety and effectiveness of the Uniglide Mobile Bearing Unicondylar Knee System. The results of this research study will be used to support application to the U.S. Food and Drug Administration (FDA) for approval so that the Corin USA, the sponsor of the study, can market the new Uniglide device in the United States.

  • Cormet Post marketing approval study
    The purpose of this study is to monitor how well the Cormet Hip Resurfacing System will perform for a period of up to 24 months after your hip is implanted. The Cormet Hip Resurfacing system received approval to be used in the United States on July-3, 2007. As part of a clinical study that was conducted for the Cormet hip resurfacing system approval, the FDA has requested Coring USA (sponsor) to enroll and monitor new subjects in the study for a period of 2 years. Approximately 120 subjects, male and female, will be enrolled in the Cormet Post Approval Study. This implant is called a metal on metal total hip and is made of cobalt chrome. This particular metal on metal total hip implant allows your surgeon to spare more bone than he would be able to with a traditional hip implant.

  • MAKO Functional Outcomes Study
    The study is designed for the evaluation of the newest knee replacement technique using the robotic arm made by MAKO Surgical Corp. The study is comparing the outcome after this robot assisted partial knee replacement surgery technique versus the traditional method of total knee replacement as well as the computer assisted method of traditional knee replacement. This study utilizes advanced armband 24-hr wearable monitors that track all the activity levels of the patients. Patients are given their activity information at the end of the 2 month period while the study tracks multiple issues related to activity before and after surgery. X-ray assessments, Physical Therapy and clinical evaluations are done for extended periods to evaluate surgery results.

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