Osteotomy, Randomized Controlled Trial
Conditions
Keywords
Patient Specific Instrumentation, Randomized controlled trial, High Tibial Osteotomy
Brief summary
Medial open wedge high tibial osteotomy is a surgery performed to treat knee osteoarthritis in young patients.Recently with our department advance of technology, the investigators performed computed tomography for the patient's lower limb and 3D reconstruct the image. Based on the 3D image, the investigators planned our planned osteotomy cut on computer software Materialize 3 and the investigators then 3D printed a metal jig that has a slot to produce the osteotomy and also protected the neurovascular bundles. Therefore these metal jigs are specific to each patients. The investigators have performed a few cases of HTO under this extra metal jig protection and guidance and noted it has improved accuracy and safety clinically. However, whether it has scientific significance difference in accuracy is not known.
Detailed description
Medial open wedge high tibial osteotomy is a surgery performed to treat knee osteoarthritis in young patients. Currently the investigators perform high tibial osteotomy under the guidance of computer navigation to achieve the required alignment. During conventional high tibial osteotomy the bone cut is done by free hand cutting, there are risks of cutting into the posterior proximal tibia compartment and transect the neurovascular bundles which is a surgical disaster and may then lead to loss of limb. And the accuracy of free hand cutting is limited by experience of surgeons. In our conventional high tibial osteotomy transection of neurovascular bundles has never happened given our meticulous surgical technique but the investigators believe an extra protection is always beneficial to our patients. Recently with our department advance of technology, the investigators performed computed tomography for the patient's lower limb and 3D reconstruct the image. Based on the 3D image, the investigators planned our planned osteotomy cut on computer software Materialize 3 and the investigators then 3D printed a metal jig that has a slot to produce the osteotomy and also protected the neurovascular bundles. Therefore these metal jigs are specific to each patients. The investigators have performed a few cases of HTO under this extra metal jig protection and guidance and noted it has improved accuracy and safety clinically. However, whether it has scientific significance difference in accuracy is not known.
Interventions
PROCEDURE3D printed patient specific metal jigs (PSI jig)
PSI jig is created based on the pre-operative CT image. Standard medial open wedge osteotomy described previously is performed. Incision is made in the midway between posteromedial border of the tibia and medial aspect of the tibial tuberosity. Sartorius fascia is cut and retracted medially to expose the medial collateral ligament (MCL). Then the PSI jig is positioned onto the tibia. Due to the jig patient specific design (individually based on each patient's CT image), it can fit closely to the proximal tibia. The slot opening on the PSI jig corresponds to 4 cm below the medial joint line and the slot design allow the sawblade cut direction toward the safe zone of the lateral cortex under fluoroscopy. The PSI Jig is removed after the bone cut completed and would not retain in patient's body.
PROCEDUREHTO with navigation
In brief, an incision is made in the midway between posteromedial border of the tibia and medial aspect of the tibial tuberosity. Sartorius fascia is cut and retracted medially to expose the medial collateral ligament (MCL). Two to three K-wires are placed 4 cm below the medial joint line toward the safe zone (an area between the tip of the fibular head and the remnant of fibular head epiphysis line) of the lateral cortex under fluoroscopy and osteotomy is done below and parallel to the k-wires using an oscillating saw leaving the lateral 10 mm intact.
Sponsors
Chinese University of Hong Kong
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Randomization will be accomplished by computer-generated randomization sequence using serially numbered opaque, sealed envelopes with patients assigned either to intervention or control groups. All investigators, research staff, patients except the surgeon performing the HTO will be blinded to the group assignment of the subjects. Nor they will be aware of the regimen prescribed during the study and evaluation periods. A randomization code will be allocated to each included subjects to maintain blindness. Randomization code will be broken only after the database had been locked. Patient rehabilitation, post-operative assessment and Data analysis are conducted by personnel blinded to the patients' randomization assignment.
Intervention model description
Control group: High tibial osteotomy with navigation Intervention group: High tibial osteotomy with navigation and PSI jig
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* symptomatic patient with medial compartment knee OA * medial compartment OA was grade 3 or milder according to Kellgren-Lawrence classification
Exclusion criteria
* lateral compartment OA * symptomatic patellofemoral compartment OA, * inflammatory arthritis, * significant loss of knee joint range in flexion (less than 100°) or in extension (less than - 10°), * ligamentous instability, * obesity with a body mass index greater than 30, * significant psychological disorder * inability to communicate in Chinese or English language
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Knee Society knee score | 1 week before surgery | Clinical and functional scores, on a 100-point scale; Knee Society score (KSS) has a Knee Score section (7 items) and a Functional Score section (3 items). Both sections are scored from 0 to 100 with lower scores being indicative of worse knee conditions and higher scores being indicative of better knee conditions. Excellent for score 80-100, Good for score 70-79, Fair for score 60-69, Poor for score below 60. |
| Knee Society function score | 1 week before surgery | Clinical and functional scores, on a 100-point scale; Knee Society score (KSS) has a Knee Score section (7 items) and a Functional Score section (3 items). Both sections are scored from 0 to 100 with lower scores being indicative of worse knee conditions and higher scores being indicative of better knee conditions. Excellent for score 80-100, Good for score 70-79, Fair for score 60-69, Poor for score below 60. |
| Oxford Knee Score | 1 week before surgery | Clinical and functional scores |
| Range of motion | 1 week before surgery | Evaluated using a manual goniometer |
| Pain Visual Analog Scale (VAS) score | 1 week before surgery | The VAS is a psychometric response scale and a measurement instrument for subjective characteristics or attitudes that cannot be directly measured. The VAS pain ranges 0-10, with 10 representing the most pain. |
| Measurement of knee displacement | 1 week before surgery | Measure the displacement (in cm) between femoral head and tibial head on a secured computer using CT scan images and scanogram images |
Countries
Hong Kong
Outcome results
None listed