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Completed

NCT Number: NCT04000672

Patient Specific Instrumentation (PSI) Referencing Osteotomy Technological Transfer - a Randomized Control Trial (RCT)

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.

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Key information

Conditions

Osteotomy Randomized Controlled Trial

Age range

18 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Prince of Wales Hospital & Alice Ho Miu Ling Nethersole Hospital

Shatin, Hong Kong

About this study

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.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

3D printed patient specific metal jigs (PSI jig)

Procedure

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.

HTO with navigation

Procedure

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.

Primary outcomes

  1. Knee Society knee score

    Time frame: 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.

  2. Knee Society knee score

    Time frame: 6 months post-op

    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.

  3. Knee Society knee score

    Time frame: 1 year post-op

    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.

  4. Knee Society knee score

    Time frame: 2 year post-op

    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.

  5. Knee Society function score

    Time frame: 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.

  6. Knee Society function score

    Time frame: 6 months post-op

    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.

  7. Knee Society function score

    Time frame: 1 year post-op

    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.

  8. Knee Society function score

    Time frame: 2 year post-op

    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.

  9. Oxford Knee Score

    Time frame: 1 week before surgery

    Clinical and functional scores

  10. Oxford Knee Score

    Time frame: 6 months post-op

    Clinical and functional scores

  11. Oxford Knee Score

    Time frame: 1 year post-op

    Clinical and functional scores

  12. Oxford Knee Score

    Time frame: 2 year post-op

    Clinical and functional scores

  13. Range of motion

    Time frame: 1 week before surgery

    Evaluated using a manual goniometer

  14. Range of motion

    Time frame: 1 week before discharge

    Evaluated using a manual goniometer

  15. Range of motion

    Time frame: 3 months post-op

    Evaluated using a manual goniometer

  16. Range of motion

    Time frame: 6 months post-op

    Evaluated using a manual goniometer

  17. Range of motion

    Time frame: 1 year post-op

    Evaluated using a manual goniometer

  18. Range of motion

    Time frame: 2 year post-op

    Evaluated using a manual goniometer

  19. Pain Visual Analog Scale (VAS) score

    Time frame: 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.

  20. Pain Visual Analog Scale (VAS) score

    Time frame: 1 week before discharge

    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.

  21. Pain Visual Analog Scale (VAS) score

    Time frame: 3 months post-op

    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.

  22. Pain Visual Analog Scale (VAS) score

    Time frame: 6 months post-op

    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.

  23. Pain Visual Analog Scale (VAS) score

    Time frame: 1 year post-op

    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.

  24. Pain Visual Analog Scale (VAS) score

    Time frame: 2 year post-op

    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.

  25. Measurement of knee displacement

    Time frame: 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

  26. Measurement of knee displacement

    Time frame: 1 year after surgery

    Measure the displacement (in cm) between femoral head and tibial head on a secured computer using CT scan images and scanogram images

Sponsors and collaborators

Lead sponsor

Chinese University of Hong Kong

Other

Registry information

Official study title

Patient Specific Instrumentation (PSI) Referencing Osteotomy Technological Transfer and Education - a PSI High Tibial Osteotomy, Double-blinded, Randomized Controlled Trial - the PROTECTED HTO (High Tibial Osteotomy) Trial

Acronym: ProtectedHTO

Important dates

Study start
2019
Primary completion
2023
Study completion
2023
First posted
Jun 27, 2019
Registry last updated
Dec 7, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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