SHould You transFer the Tubercle?

Patellofemoral Dislocation Clinical Trial

— SHYFT  

Official title:

A Randomized Clinical Pilot Trial Comparing Isolated Medial Patellofemoral Ligament Reconstruction to Medial Patellofemoral Ligament Reconstruction Combined With Tibial Tubercle Osteotomy: SHould You transFer the Tubercle (SHYFT)?

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05759039
• Other study ID #: REB17-1256
• Status: Recruiting
• Phase: N/A
• Start date: September 1, 2023
• Est. completion date: September 1, 2026

Study information

• Verified date: December 2023
• Source: Banff Sport Medicine Foundation
• Contact: Laurie A Hiemstra, MD, PhD
• Phone: 403 760 2897
• Email: hiemstra[@]banffsportmed.ca
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The aim of this study is to investigate the role of tibial tubercle osteotomy (TTO) on the subjective and objective outcomes following medial patellofemoral ligament reconstruction (MPFL-R) in patients with an increased tibial tubercle-trochlear groove (TT-TG) distance with or without patella alta.

This Pilot RCT will assess the feasibility of conducting this study for:

1. The ability to recruit study patients

2. Adherence to the study protocol

3. Completion rates of patient follow-up at a minimum of 12 months post-operative

Description:

For patients with recurrent lateral patellofemoral instability, a medial patellofemoral ligament reconstruction (MPFL-R) consistently provides significant improvements in symptoms, quality of life, and return to sport. During an MPFL-R the surgeon will place a soft tissue graft from the medial patella to the femur. The graft used to create the new MPFL can be autograft (usually hamstring tendon) or allograft.

The tibial tubercle osteotomy (TTO) is a procedure designed to change the vector of the pull of the quadricep muscles by moving the insertion point of the patellar tendon. This is achieved by transferring the tendon with a block of bone to allow for consistent and reliable healing. The TTO is a versatile procedure that can move the patellar tendon insertion medially, anteriorly, or distally, or a combination of these directions. It can be used to correct a lateralized tibial tubercle or patella alta.

Despite the association of an increased TT-TG distance with patellofemoral instability, it has been difficult to demonstrate a correlation with patient outcomes after patellar stabilisation surgery. In addition, studies have been unable to correlate the pre-operative presence of patella alta with clinical outcomes after MPFL-R.

This randomized clinical pilot trial will randomly allocate patients with lateral patellofemoral instability and an elevated TT-TG distance with or without patella alta ato receive either an isolated MPFL-R or an MPFL-R in combination with a correcting TTO (medializing, distalizing, or a combination of both).

Patients will be followed for two years post-operative with subjective outcome measures and objective clinical and functional testing.

The study groups will be:

1. Isolated MPFL-R

2. MPFL-R with a TTO

The primary outcome measures will be:

1. Number of study patients recruited

2. Adherence to the study protocol (number of protocol deviations)

3. Follow-up completion rates of study patients at a minimum of 12 months post-operative

Secondary outcome measures include the Banff Patellar Instability Instrument 2.0 (BPII 2.0), functional testing, clinical assessment, complications, re-dislocation rate, post-operative pain scores, patient satisfaction, and patient-reported outcome scores.

If feasibility is demonstrated via this Pilot RCT, a larger RCT will be designed to answer important questions on how to optimize outcomes and limit morbidity after MPFL-R.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 30
• Est. completion date: September 1, 2026
• Est. primary completion date: December 31, 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 13 Years to 30 Years

Eligibility

Inclusion Criteria:

• Age 13-30 years

• Symptomatic recurrent lateral patellofemoral instability

• TT-TG =15mm measured on MRI or =18mm on CT scan

• Closed physes (confirmed on knee x-rays)

Exclusion Criteria:

• Caton-Deschamps ratio = 1.4 on lateral radiographs

• Femoral anteversion = 25 degrees on diagnostic imaging rotational profile

• Tibial external rotation = 45 degrees on diagnostic imaging rotational profile

• High-grade trochlear dysplasia requiring trochleoplasty

• Significant osteoarthritis on skyline plain imaging (Kellgren Lawrence grade = 2)

• A chondral lesion of the patellofemoral joint that is undergoing a cartilage restoration procedure.

• Unable to complete computer-based outcome questionnaires

• Pregnant (at time of surgery)

Related Conditions & MeSH terms

• Medial Patellofemoral Ligament Reconstruction
• Patellofemoral Dislocation
• Tibial Tubercle Osteotomy

Intervention

Procedure:
• Medial patellofemoral ligament reconstruction
Medial patellofemoral ligament reconstruction

Locations

Country	Name	City	State
Canada	Banff Sport Medicine	Canmore	Alberta

Sponsors (3)

Lead Sponsor	Collaborator
Banff Sport Medicine Foundation	Canadian Orthopaedic Foundation, CONMED Corporation

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Study Feasibility - patient recruitment	Number of study patients recruited	12-months post-operative
Primary	Study Feasibility - protocol adherence	Adherence to the study protocol (total number of protocol deviations)	12-months post-operative
Primary	Study Feasibility - follow-up completion	Number of patients completing follow-up a minimum of 12 months post-operative	12-months post-operative
Secondary	Banff Patellofemoral Instability Instrument (BPII 2.0)	Disease-specific patient-reported outcome measure that assesses quality of life across 5 domains. Scored out of 100, with 100 representing the maximum score for disease-specific quality of life.	Baseline, and 6-,12- & 24-months post-operative
Secondary	Functional Outcomes - Hop Testing	Limb Symmetry Index on 4 single-leg hop test battery (assessed as percentage score operative / non-operative limb)	6-, 12- & 24-months post-operative
Secondary	Patellar Apprehension Test	Rate of positive patellar apprehension	6-, 12- & 24-months post-operative
Secondary	Complications	Rate of post-operative complications including infection, blood clots, reduced range of motion, persistent pain, persistent swelling, and re-dislocations	6-, 12- & 24-months post-operative
Secondary	Post-operative Knee Pain	Post-operative pain score measured on a 10-point visual analogue scale	6-, 12- & 24-months post-operative
Secondary	Patient satisfaction	Measured on a 5-point Likert scale	6-, 12- & 24-months post-operative