Degree-Faqs.com

mpfl is tightest in what degree of flexion

by Christine Auer Published 1 year ago Updated 8 months ago
image

What is the correct fixation position for the MPFL graft?

Tilt analysis showed that patella rotated laterally until 85° of knee flexion for intact MPFL condition and until 70° for resected MPFL condition and after rotated medially. Static tests showed that patellar stability was significantly affected by MPFL resected condition in …

What happens to the MPFL in recurrent instability?

Jan 29, 2015 · The basis for this recommendation is established from prior research, which suggests that (1) the MPFL is the most important patellar stabilizer during the first 30° of knee flexion until the patella engages the trochlear groove, 1,5 (2) overtightening the graft in extension results in iatrogenic medial subluxation of the patella, and (3) overtightening the graft in flexion …

What is the MPFL and why is it important?

Amis has shown that the native MPFL is not a very robust ligament; when compared to others in the knee it only withstands loads of about 208N when tested to failure at 25 mm of displacement. 31 The MPFL provides from 50-60% of the restraint to lateral patellar translation during the ranges of 0-30 degrees of knee flexion. 22,24,25 If the MPFL is sectioned, the patella displaces …

What is the medial patellofemoral ligament (MPFL)?

The clinical presentation of an overtight medial patellofemoral ligament (MPFL) reconstruction can differ depending on whether it is too tight in extension (extensor lag) or too tight in flexion (anterior knee pain and loss of flexion). We report one …

image

What is the MPFL?

The Medial Patellofemoral Ligament (MPFL) is an hour-glass shaped ligament made of bands of retinacular tissue. The MPFL plays a significant role in the stabilization of the medial aspect of the patella.

Where is the MPFL located?

The medial patellofemoral ligament is located in the second layer of three soft tissue layers within the medial aspect of the knee. The MPFL originates from a triangular space running between the adductor tubercle, medial femoral condyle and gastconemius tubercle, superior to the superficial medial collateral ligament ...

What is the function of the medial patellofemoral ligament?

The main function of the medial patellofemoral ligament is to provide restraint to the patella during early knee flexion (0-30 degrees). It acts in maintaining appropriate patellar tracking within the trochlear groove, while providing 50-60% of the restraining force against lateral displacement.

What is the best treatment for lateral patellar dislocation?

Conservative treatment, especially after the first lateral patellar dislocation, has been regarded as the most appropriate course of treatment. Rehabilitation with Physical Therapy and bracing is the prescribed treatment for lateral patellar dislocation.

What is the function of MPFL?

In recurrent instability, the MPFL is often torn or stretched. The function of the MPFL is critical in stabilizing the patella in early knee flexion (0-30°). This occurs when the patella is not engaged in the trochlea. In the setting of a normal trochlea, the lateral trochlea provides a static restraint to lateral translation of the patella at increased knee flexion.5 Though not a primary cause of patella instability, the lateral structures of the knee can contribute to the recurrent instability of the patella when medial structures are attenuated.

Why do you need lateral lengthening?

If the lateral structures are tight or shortened, lateral lengthening may be required in order to achieve realignment of the patella for appropriate balancing of the parapatellar structures. On exam,

What is patella dislocation?

Patella dislocations are significant injuries, comprising about 2-3% of acute knee injuries.1 Current initial treatment for first-time patella dislocations is often nonsurgical, consisting of aggressive rehabilitation, occasional bracing and return to activities. Recurrent instability can frequently occur after a primary dislocation, leading to disability.1 The medial patellofemoral ligament (MPFL) has been shown to be the primary structure injured during a patella dislocation. Furthermore, the MPFL has been shown to be the primary static restraint to lateral translation of the patella.2 In the past, plication techniques have been used to attempt to tighten the medial patellofemoral ligament. These techniques are not as effective in preventing recurrence of dislocation as reconstruction of the MPFL.3,4 Contemporary techniques for addressing patella instability focus on pathologic structures and anatomically restoring the static restraint to lateral patella translation with a medial patellofemoral ligament (MPFL) reconstruction. The goal of these procedures is to recreate the primary ligamentous restraint to prevent lateral patella instability.4 The technique described here uses an allograft to recreate the static checkrein effect of the medial patellofemoral ligament. Additionally, if the lateral structures are tight or shortened, lateral lengthening may be required for appropriate balancing of the parapatellar structures in certain situations.

Where to place allograft tendon?

Place the allograft tendon mid portion within the patella trough. Create two equal limbs that will be secured into the femoral socket. These two limbs will closely re-approximate the wide insertion of the medial patellofemoral ligament on the medial surface of the patella.

What is the Smith and Nephew technique guide?

Created under close collaboration with the surgeon, it contains a summary of medical techniques and opinions based upon his training and expertise in the field, along with his knowledge of Smith & Nephew’s products. Smith & Nephew does not provide medical advice and recommends that surgeons exercise their own professional judgement when determining a patient’s course of treatment. This guide is presented for educational purposes only. Prior to performing this technique, or utilizing any product referenced herein, please conduct a thorough review of each product’s indications, contraindications, warnings, precautions and instructions as detailed in the Instructions for Use provided with the individual components.

image
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9