Medial patellofemoral ligament. stabilizer of patella during initial 30 degree of flexion. More than 18 techniques of reconstruction described. Runs in layer 2 on medial aspect of the knee. Origin- 1.9mm anterior/3.8 mm distal to adductor tubercle.(Laparade JBJS- Am.07) Insertion – proximal 2/3 of patella Along Distal edge of VMO Broad insertion over 28.2+_ 5.6 mm over proximal 2/3 patella. Average length 59.8mm +_ 4.8mm. Passive- Trochlear constraints Depth ,length(Height) Patellar engagement Capsular ligamentous tethers, especially MPFL (Hautamaa, Fithian et al. 1998) Dynamic elements Simulated muscle tension has little effect on patellar mobility. Regardless of flexion angle (Scnavongers, Farahmand et al 2003

1. D R S A M I R D W I D M U T H E
M S O R T H O D N B O R T H O
A R T H R O S O C P Y F E L L O W S O U T H K O R E A
I N T E G R A S P E C I A L T Y C L I N I C S , N A G P U R
Medial Patello-femoral
Ligament Reconstruction

2.  Medial patellofemoral
ligament.
 stabilizer of patella during
initial 30 degree of flexion.
 More than 18 techniques of
reconstruction described.

3. Overview
 Biomechanics of MPFL.
 Indications.
 MPFL recon. Technique principals.
 Rehabilitation.
 Complications.

4. Indications –
 Episodic lateral patellar instability due to excessive
laxity of medial retinacular patellar stabilizers.
 MPFL laxity to be documented by physical
examination , stress radiography , EUA.

5. Contraindications
 Absence of retinacular laxity
 Chronic pain
 Significant patello-femoral arthrosis.
 The permanently dislocated or habitually
dislocating patella.
 TTTG more than 20mm, Q angle more than 20
degrees.
 Patella alta.
 Skeletally immature.

6. Radiological assessment
 Merchant / lateral radiograph
Trochlear dysplasia.
Patello-femoral congruence.
Genu valgum.
 Axial Imaging
Trochlear morphology
TTTG
Patellofemoral cartilage

7. Objectives of procedure
 Checkrein vs. lateral displacement.

8. Technical principals
 Graft selection
 Selecting femoral and patellar attachment.
 Patellar tunnels.
 Tension and Fixation.

9. Graft selection
 Semitendinosus auto graft
 Quadriceps
 Adductor tendon
 Patellar tendon
 Allograft
Length of graft depends upon single or double strand
technique.

10. Femoral tunnel placement
Radiographic Landmarks for Femoral Tunnel Placement in Medial
Patellofemoral Ligament Reconstruction. Philip B. Schöttle,
AJSM 2007
Extension of posterior cortex
Along posterior edge of Blumensaat line
Posterior origin of medial femoral condyle.

11. Selecting patellar attachment.
Insertion –
 Proximal 2/3 of patella
 Along Distal edge of
VMO
 Avoid articular
penetration

12. Fixation of graft

13. Fixation of graft
Suture anchors over patella
and interference screw over femur

14. Basket weave technique
Dr. Pranjal Kodkani

15. Patellar tendon Quadriceps tendon
Adductor tendon

16. How does graft tension affect the joint
 Minimal tension (1lb) does not alter patellofemoral
contact pressure through ROM. (Melegari AJSM 08)
 Excessive loads (10 N or 40 N) while reducing lateral
translation will increase patellofemoral contact
pressure over the medial facet.
( Beck AJSM 07)
Remove all slack, fix with no tension.

17.  Fix in 45 degrees of flexion.
 Isometry during ROM may not be needed as graft
relaxes in flexion.
 Lateral release, distal bony procedure in selected
patients.

18. Rehabilitation
 WBAT in knee immobilizer.
 Immediate ROM (0-90 x 5 weeks, then unrestricted)
 Isometric quad strengthening.
 Knee immobilizer discontinued when good quad
control.
 Return to athletic participation 12-16 weeks.

19. Complications
 Recurrent instability.
 Medial facet overload (graft tension)
 Patella fracture.
 Hardware prominence.

20. Summery
 Understanding the anatomy & biomechanics MPFL
 Selection proper anatomic bony attachments
are important for successful MPFL reconstruction with
different techniques described.

21. Thanks