MPFL Reconstruction

 1.  MPFL reconstruction

 

Indication

- patient with history initial traumatic dislocation

- also indicated in patient with laxity to act as a check rein

 

Grafts

 

1.  Y Graft

- double ST autograft into Y

 

2.  Single limb free semitendinosus autograft

- limb to patella via endobutton

 

 

Schottle's Point

 

Schottle AJSM 2007

- cadaveric study

- 1 mm anterior posterior cortex

- 2 mm distal to MFC origin

- above blumensaats

 

 

Technique

 

A. Patella fixation

- incision along medial patella

- 2 drill holes in patella

- attach ends of graft, pass into patella, secure with anchor of choice

- pass graft superficial to capsule

 

B. Femoral fixaiton

- best to use II to find point

- stem between medial epicondyle and adductor tubercle

- Schottle's Point

- drill wire across femur, drill hole for fixation screw

- pass doubled graft into tunnel

- set at 30^o flexion

- ensure doesn't dislocation laterallly

- don't overtighten

- secure with screw

 

Xrays 1

 

Tunnel too anterior / tight in flexion

 

 

Xray 2

 

Finding Schottles Point

 

 

Results

 

Nomura et al J Arthroscopy 2006

- recurrent dislocation, no malalignment

- 83% G/E results

- no redislocation at  2 year follow up

 

Howells JBJB Br 2012

- 211 procedures in 193 knees

- all TTTG < 18

- most moderate trochlea dysplasia

- no redislocations at 16 months

 

Shah et al AJSM 2012

- Systematic review MPFL

- 26% complication rate

- 4/629 (0.6%) fractures

- 26/629 (4%) stiffness

- 23/629 (3.7%) failure rate