First exprerience with patient specific custom made total knee allignment guides compared with conventional intramedullary alignment method for total knee arthroplasty.

Preliminary Experience with the Custom-fit Total Knee Arthroplasty. Comparison with a Matched Control Group

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

NL-OMON

Registry ID

NL-OMON27913

Enrollment

Registered

2011-12-08

Start date

2011-01-01

Completion date

Unknown

Last updated

2024-02-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

total knee arthroplasty, allignment, blood loss, patient specific custom made guide,operation time

Interventions

Recently, a patient specific alignment guide, SignatureTM Personalized Patient Care (SPPC) (Biomet, Inc., Warsaw, IN) was developed, based on a preoperative MRI-scan of the patient’s leg. With this al

Eligibility

Inclusion criteria

Inclusion criteria: Forty knees in 39 patients (25 women, 14 men) were operated on by means the SPPC procedure between December 2009 and March 2010 and were eligible for inclusion in this case control study. Patients scheduled for primary total knee replacement for osteoarthritis were included.

Exclusion criteria

Exclusion criteria: Patients with a body-mass-index above 35, patients with active infection, either in the knee or general infection, patients with a history of osteotomy and patients with metal near the knee joint were excluded.

Design outcomes

Primary

Measure	Time frame
Alignment, in terms of percentages of outliers, was expected to be superior in the SPPC group, compared to the conventional intramedullary alignment technique. Long leg standing x ray: 1. Mechanical axis (both preoperative and post-operative) = angle between the mechanical axis of femur and tibial mechanical axis. How to measure: Center of rotation of the femoral head (just center of the femoral head on long leg standing x-ray) to center (middle) of distal femur (= femoral mechanical axis) and center (middle) tibial plateau to the center (middle) of the thalus (= mechanical axis-tibia). Here are two angles whose sum is 360 degrees. Example: The system will give an angle of 182gr and 178gr medial-lateral. Then please note the angle of 178gr. This means that the patient has a 2 degree varus long leg standing x-ray; 2. State of the individual components relative to the femur and tibia mechanical axis of femur and tibia. Femur: Pulling together on distal condyles of femoral component. Then draw lines previously drawn line for mechanical axis of the femur. Tibia: line drawing below the tibial plateau. Then draw lines previously drawn line for mechanical axis of the femur. In both cases there is an additional angle of. Important: Again, like the medial corner record! (See picture). Ex.: The system provides for the femoral component angle of 87 degrees from 93 degrees laterally and medially. So then like angle of 93 degrees recorded. This means in this case the femoral component in valgus is 3 degrees with respect to the mechanical axis of the femur. On the lateral picture: 3. Femoral component position relative to anterior cortex. How to measure: Line through distal femoral component. Tangent of the anterior femoral cortex. Coming back from two angles that are supplementary; 4. Posterior tibial cortex relative position tibiacomponent. How to measure: Line at the bottom of tibiacomponent. Tangent to posterior tibial cortex. Coming back from two angles that a	—

Measure

Time frame

Alignment, in terms of percentages of outliers, was expected to be superior in the SPPC group, compared to the conventional intramedullary alignment technique. Long leg standing x ray: 1. Mechanical axis (both preoperative and post-operative) = angle between the mechanical axis of femur and tibial mechanical axis. How to measure: Center of rotation of the femoral head (just center of the femoral head on long leg standing x-ray) to center (middle) of distal femur (= femoral mechanical axis) and center (middle) tibial plateau to the center (middle) of the thalus (= mechanical axis-tibia). Here are two angles whose sum is 360 degrees. Example: The system will give an angle of 182gr and 178gr medial-lateral. Then please note the angle of 178gr. This means that the patient has a 2 degree varus long leg standing x-ray; 2. State of the individual components relative to the femur and tibia mechanical axis of femur and tibia. Femur: Pulling together on distal condyles of femoral component. Then draw lines previously drawn line for mechanical axis of the femur. Tibia: line drawing below the tibial plateau. Then draw lines previously drawn line for mechanical axis of the femur. In both cases there is an additional angle of. Important: Again, like the medial corner record! (See picture). Ex.: The system provides for the femoral component angle of 87 degrees from 93 degrees laterally and medially. So then like angle of 93 degrees recorded. This means in this case the femoral component in valgus is 3 degrees with respect to the mechanical axis of the femur. On the lateral picture: 3. Femoral component position relative to anterior cortex. How to measure: Line through distal femoral component. Tangent of the anterior femoral cortex. Coming back from two angles that are supplementary; 4. Posterior tibial cortex relative position tibiacomponent. How to measure: Line at the bottom of tibiacomponent. Tangent to posterior tibial cortex. Coming back from two angles that a

—

Secondary

Measure	Time frame
We expected operation time, blood loss and hospitalization to be lower/shorter in the SPPC group than in the conventional total knee alignment group.	—

Contacts

Public ContactB. Boonen

Orthopedic Department, Orbis Medisch Centrum dr H van de Hoffplein 1

boonenbert@gmail.com

Outcome results

None listed

Source: NL-OMON (via WHO ICTRP)