Medial Patellofemoral Dislocation, Medial Patellofemoral Ligament Reconstruction
Conditions
Keywords
MPFL, Knee, Medial Patellofemoral Ligament, Surgery
Brief summary
The purpose of this project is to investigate the treatment outcome after MPFL reconstruction in children as a treatment for chronic patellar instability, where the superficial part of the quadriceps tendon is fixed to the femur with anchors. The outcome will be compared with a healthy cohort matched on age and gender.
Detailed description
Lateral patella dislocation (PL) is defined as a total dislocation of the patella out of the trochlea. In chronic patella instability, where the patella has been repeatedly dislocated, the treatment is most often surgical. The main ligamentous structure that stabilizes the patella against lateralization is the medial patello-femoral ligament (MPFL). The MPFL is a centimeter-thin ligamentous structure that runs from the upper medial patellar border to the medial femoral epicondyle. This ligament is torn in more than 90% of cases of PL and healing of the ligament is often insufficient, especially if there are predisposing factors in the knee joint such as dysplasia of the patello-femoral joint, high standing patella (patella alta) and hypermobility. MPFL reconstruction (MPFL-r) can be performed with many different surgical techniques, but the basic principle is to use autologous tendon tissue to create a new MPFL by anchoring the new tendon tissue to the medial patellar border and the medial femoral epicondyle, while ensuring isometry of the reconstruction. A number of different methods have been described for anchoring the new MPFL to the patella and femoral condyle. The most commonly used type of graft for MPFL-r is the gracilis tendon, which is fixed with screws in the femur bone preceded by drilling a channel in the femoral condyle. In non-grown patients, the growth zone of the distal femur is very close to the anatomical attachment of the MPFL. This poses a problem as a reaming that hits the growth zone carries a theoretical risk of compromising growth around the knee. In addition, up to 50% of patients describe pain at 1 year after surgery if screw fixation is used in the medial femoral condyle. A new MPFL-r method using a superficial portion of the quadriceps tendon fixed with an anchor provides a good 2-year result compared to gracilis tendon and screw fixation. The effectiveness and long-term efficacy of MPFL surgery with the quadriceps tendon for children is not well described in the literature. At the Department of Sports Traumatology in Aarhus, Denmark, the quadriceps technique has been used on non-adult patients since 2016. In this study, the investigators want to include the 80 patients who have undergone this MPFL-r since 2016 with the quadriceps tendon technique and have a minimum of 2 years of follow-up. This patient group will compared to a healthy cohort matched on age and gender.
Interventions
Children with patella dislocations are operated from 2016-2022 with a quadriceps knee cap stabilization technique.
Sponsors
Study design
Eligibility
Inclusion criteria
- Intervention group: * MPFL-reconstruction with Quadriceps tendon graft * Open physis at surgery date * Minimum 2 years Follow up
Exclusion criteria
- Intervention group: * More surgeries in index knee * MPFL-r in opposite knee * MPFL revision in index knee Inclusion Criteria - Healthy group: * No knee problems
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Kujala (Anterior Knee Pain Scale) | 24 month | Patient reported outcome score, 0=worst and 100=best |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Donor site morbidity score, 0=worst and 100=best | 24 month | Patient reported outcome score |
| Numerical Rating Scale (NRS-pain score) | 24 month | Patient reported outcome score, 0=Best and 10=worst |
| Knee pain | 24 month | Palpatory pain in relation to graft fixation in femur on a four-point likert scale (0=no pain, 1=mild pain, 2=moderate pain, 4=severe pain) |
| One-legged single hop for distance | 24 month | Physical performance test |
| Tegner (Activity Score) | 24 month | Patient reported outcome score, 0=worst and 10=best |
| Side-to-side hop test | 24 month | Physical performance test |
| Quadriceps Strength test | 24 month | Physical performance test. Hand held dynamometry |
| Gluteus Medius Strength test | 24 month | Physical performance test. Hand held dynamometry |
| One-legged triple hop for distance | 24 month | Physical performance test |
Countries
Denmark