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Total Knee Replacement Component Alignment Using Manual Versus Custom Instrumentation

Total Knee Replacement Component Alignment Using Manual Versus Custom Instrumentation

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02579174
Enrollment
112
Registered
2015-10-19
Start date
2015-01-31
Completion date
2020-11-30
Last updated
2022-11-15

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

Conditions

Osteoarthritis of Knee

Brief summary

1. To determine whether the low-dose, biplanar x-ray imaging (EOS) has the same accuracy as computed axial tomography (CT) 2. To validate low-dose, biplanar x-ray imaging (EOS) as a tool to evaluate 3-dimensional alignment of Total Knee Replacement implants. 3. To evaluate differences in total knee replacement implant alignment in patients whose arthroplasty is performed using manual or custom instrumentation derived from preoperative CT

Detailed description

Achieving optimal prosthetic alignment of the femoral, tibial and patellar components during Total Knee Replacement (TKR) is of great importance as it contributes to better function, less pain and improved quality of life.TKR requires accuracy in the execution of bone cuts in the correct orientation to the coronal, sagittal and axial planes. Malposition potentially leads to increased mechanical stress on the bearing surfaces and inevitably to earlier loosening. Computed Axial Tomography (CT) is the gold standard technique to evaluate implant alignment in the coronal, sagittal and axial planes. As such, CT has imaging has been used to create custom instrumentation with purported likely improvement in surgical outcomes. Customized instrumentation created from a preoperative CT has been shown to be safe and effective, with no reported difference in patient outcomes and similar total knee arthroplasty component alignment. However, taking into consideration CT's high levels of radiation, cost expenses and its inability to obtain images of the limb in weight-bearing position, CT scan cannot be used routinely as a postoperative tool to evaluate TKR implant positioning. The imaging system manufactured by EOS Imaging (formerly Biospace Med, Paris) is a biplanar, low-dose radiation, full body, high resolution, radiological imaging system allowing simultaneous acquisition in the coronal and sagittal planes and in standing position.EOS' main benefits are the considerable reduction in radiation dose (up to 1000 times less than for CT and ten times less than the plain radiography) by using a gaseous detector. George Charpak, the inventor, was awarded the Nobel Prize in 1992 for this work. Moreover, the EOS system can provide 3D images by using the appropriate software algorithms, thus providing a low-radiation alternative to CT.

Interventions

DEVICEMedacta GMK Sphere

Sponsors

Northwestern University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Eligibility

Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No

Inclusion criteria

* Radiographically confirmed diagnosis of osteoarthritis (OA) * Failure of non-operative treatment for the diagnosis of symptomatic osteoarthritis * Age greater than 18 years * Desire to proceed with elective TKR * Completion of informed consent and signature of written consent form

Exclusion criteria

* Ligamentous instability that may necessitate a constrained TKR implant * Retained hardware in the distal femur or proximal tibia of the operative extremity * Medical contraindication to undergo preoperative CT, or inability to tolerate preoperative CT

Design outcomes

Primary

MeasureTime frameDescription
Post-Operative Hip-Knee-Angle (HKA)Pre-operative, 6 wks. post-opMeasured HKA change from pre-operative EOS longstanding X-ray to post-operative EOS at 6wks. comparing groups receiving manual instrumentation versus custom instrumentation

Secondary

MeasureTime frameDescription
Tibial Varus DeformityPre-operative, 6 wks. post-opMeasured change between pre-operative planning report & post-operative EOS longstanding radiograph in varus deformity of the operative joint
Femoral Valgus DeformityPre-operative, 6 wks. post-opMeasured change between pre-operative planning report & post-operative EOS longstanding radiograph in varus deformity of the operative joint
Tibial Posterior Slope (Mean Deviation)Pre-Operative - 6 wk. Post-OperativeDeviation from pre-operative planning template & 6 wk. post-operative longstanding EOS radiograph

Countries

United States

Participant flow

Participants by arm

ArmCount
Manual (Tibia) and Manual (Femur)
Knee replacement with Medacta GMK Sphere implants using manual instrumentation for both the tibia component and the femur component Medacta GMK Sphere
18
Manual (Tibia) and Custom (Femur)
Knee replacement with Medacta GMK Sphere implants using manual instrumentation for the tibia component and custom instrumentation for the femur component Medacta GMK Sphere
16
Custom (Tibia) and Custom (Femur)
Knee replacement with Medacta GMK Sphere implants using custom instrumentation for both the tibia component and the femur component Medacta GMK Sphere
16
Custom (Tibia) and Manual (Femur)
Knee replacement with Medacta GMK Sphere implants using custom instrumentation for the tibia component and manual instrumentation for the femur component Medacta GMK Sphere
16
Total66

Baseline characteristics

CharacteristicTotalManual (Tibia) and Manual (Femur)Manual (Tibia) and Custom (Femur)Custom (Tibia) and Custom (Femur)Custom (Tibia) and Manual (Femur)
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
55 Participants18 Participants11 Participants15 Participants11 Participants
Age, Categorical
Between 18 and 65 years
11 Participants0 Participants5 Participants1 Participants5 Participants
Age, Continuous65.82 years
STANDARD_DEVIATION 8.17
68.39 years
STANDARD_DEVIATION 9.91
63.37 years
STANDARD_DEVIATION 5.25
68.77 years
STANDARD_DEVIATION 7.22
67.05 years
STANDARD_DEVIATION 8.67
Race and Ethnicity Not Collected0 Participants
Sex: Female, Male
Female
38 Participants7 Participants9 Participants10 Participants12 Participants
Sex: Female, Male
Male
28 Participants11 Participants7 Participants6 Participants4 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 180 / 160 / 160 / 16
other
Total, other adverse events
0 / 180 / 160 / 160 / 16
serious
Total, serious adverse events
0 / 180 / 160 / 160 / 16

Outcome results

Primary

Post-Operative Hip-Knee-Angle (HKA)

Measured HKA change from pre-operative EOS longstanding X-ray to post-operative EOS at 6wks. comparing groups receiving manual instrumentation versus custom instrumentation

Time frame: Pre-operative, 6 wks. post-op

Population: Sub group analysis of only participants who received both manual or both custom instrumentations.

ArmMeasureValue (MEAN)Dispersion
Total Component Manual InstrumentationPost-Operative Hip-Knee-Angle (HKA)2.14 DegreesStandard Deviation 1.79
Total Component Custom InstrumentationPost-Operative Hip-Knee-Angle (HKA)3.06 DegreesStandard Deviation 2.33
Secondary

Femoral Valgus Deformity

Measured change between pre-operative planning report & post-operative EOS longstanding radiograph in varus deformity of the operative joint

Time frame: Pre-operative, 6 wks. post-op

Population: Combined analysis of participants who received manual vs custom femoral instrumentation.

ArmMeasureValue (MEAN)Dispersion
Total Component Manual InstrumentationFemoral Valgus Deformity1.53 DegreesStandard Deviation 1.22
Total Component Custom InstrumentationFemoral Valgus Deformity1.76 DegreesStandard Deviation 1.31
Secondary

Tibial Posterior Slope (Mean Deviation)

Deviation from pre-operative planning template & 6 wk. post-operative longstanding EOS radiograph

Time frame: Pre-Operative - 6 wk. Post-Operative

Population: Combined analysis of participants who received manual vs custom tibial instrumentation

ArmMeasureValue (MEAN)Dispersion
Total Component Manual InstrumentationTibial Posterior Slope (Mean Deviation)2.70 DegreesStandard Deviation 1.56
Total Component Custom InstrumentationTibial Posterior Slope (Mean Deviation)2.43 DegreesStandard Deviation 1.78
Secondary

Tibial Varus Deformity

Measured change between pre-operative planning report & post-operative EOS longstanding radiograph in varus deformity of the operative joint

Time frame: Pre-operative, 6 wks. post-op

Population: Analysis combining groups receiving manual vs custom tibial instrumentation.

ArmMeasureValue (MEAN)Dispersion
Total Component Manual InstrumentationTibial Varus Deformity1.00 DegreesStandard Deviation 0.79
Total Component Custom InstrumentationTibial Varus Deformity1.38 DegreesStandard Deviation 1.21

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026