Medial patellofemoral ligament reconstruction ---- an update on techniques used. This lecture was taken by me at Trinity Arthroscopy Course, Chandigarh.

1. DR DHANANJAYA SABAT MS,DNB,MNAMS
ASSISTANT PROFESSOR
DEPARTMENT OF ORTHOPAEDICS
MAULANA AZAD MEDICAL COLLEGE
NEW DELHI
MPFL RECONSTRUCTION:
INDICATION & TECHNIQUE

2. The MPFL is
 Condensation of the medial retinaculum
 Vertically oriented
 Extracapsular structure
 Found in layer 2 of the 3 layer (Warren and
Marshall)
Primary medial restraining structure to lateral
displacement of the patella and contributes up to 80% of
the medial restraining forces to the patella.
In cases of full patellar dislocation the MPFL has
limited ability to lengthen.
The capacity of the MPFL to heal is also limited
OVER VIEW

3.  5- 10 mm proximal and 2-5 mm
posterior to the medial epicondyle
 In the saddle between the medial
epicondyle and the adductor tubercle.
 Approximately 2 mm anterior and 4
mm distal to the adductor tubercle.
 The width of the MPFL at the femoral
insertion≈ 10 mm.
FEMORAL ATTACHMENT

4.  At the junction of the proximal and
middle thirds of the patella
 Typically at the location where the
perimeter of the patella becomes more
vertical.
 Mean width of insertion 28 mm,
i.e. wider than its femoral attachment.
PATELLAR ATTACHMENT

5. ME
AT

6. Medial PatelloTibial Ligament (MPTL)
 more superficial than the MPFL
 Oblique condensation of the
medial patellar retinaculum
 Tibia l attachment: ≈ 1.5 cm
below the joint line, close to the
insertion of the medial collateral
ligament
 Uniquely positioned to help resist superior and
superolateral translation of the patella. However, the role
in resisting lateral patellar displacement is debated,
ranging from being an important secondary stabilizer to
being functionally unimportant.

7. GOALS OF SURGICAL TREATMENT
1. To reestablish the natural check-rein
against lateral patellar motion
prevent further lateral dislocations, while
allowing return to a full and active lifestyle.
2. To reestablish normal limits of passive
lateral patellar motion
Normally 5-lb displacing force with the knee at 30°
flexion results in 7–9 mm of lateral displacement.

8. MPFL Tear: Repair or Reconstruction??
 Acute repair:
mixed results (Christiansen)
Upto 20% failure rate ( same as nonoperative t/t)
etter result with avulsions
Open > Arthroscopic
 Late repair or imbrication of chronically lax tissue: high
failure rate, not recommended
 Reconstruction: most successful ≈ 95%

9. Recurrent Patellar Dislocation
Acute Patellar Dislocation: rare
 Osteochondral injury at time of
dislocation
 Failure to improve with nonoperative
care
 Continued gross instability
 Injury to the MPFL-VMO mechanism
 High level athletes that suffered a
nontraumatic dislocation
INDICATIONS
for Isolated MPFL Reconstruction

10. INDICATIONS
for Isolated MPFL Reconstruction
Failure of conservative therapy for at least 3
months in association with mechanical
instability.
 Rule out functional instability (ligamentous laxity,
muscular weakness, poor body mechanics )
 Rule out psychological factors, in association with
anterior knee pain, as the presence of these tend to
lead to a poor outcome from surgery.

11. Ideal Candidate
 < 25° of Q angle
 No cartilage session
 Trochlear morphology; normal or type A dysplasia
 Tibial tuberosity–trochlear sulcus angle = 0 – 5 valgus or a TT
TG distance < 20 mm
 No patella alta (Caton-Deschamps <1.2 / Insall-Salvati <1.4)
 Patellar tilt less than 20 when measured on an axial image, using
the posterior femoral condyles as a reference line, or some tilt but no
lateral tightness on physical examination with the patella reduced
 30, 60, 90 degrees axial views in addition to AP and lateral views may
usually give enough information.
 CT or MRI is more useful in cartilage lesion, lateral tilt near extension
and trochlear deformity.

12. As adjunct to:
 Trochleoplasty
 Distal realignment
 Varus Femoral Osteotomy (VFO)
Other Indications
for MPFL Reconstruction

13. CONTRAINDICATIONS
for MPFL Reconstruction
 Isolated patellofemoral pain
 Excessive lateral
patellofemoral tilt and/or
translation on imaging
without history and
physical examination
evidence of recurrent
lateral patella
dislocations.
The MPFL is not meant to “pull” the patella into
position. Its role is to stabilize a located patella against
excessive lateral force

14. Presence of J tracking alone, in the absence of other
objective clinical signs and symptoms (knee swelling, repeated
falling epsodes)
J-tracking : the patella appears to take the course of an inverted
J during the initiation of early flexion. The patella begins lateral
to the trochlea and suddenly moves medially, appearing to
“hop” into the trochlear groove.
The complete reasons for J-tracking are debated, but likely
include both soft tissue and bony components.
J tracking can be well tolerated by children.
An isolated MPFL reconstruction is unlikely to
eliminate patella J-tracking.
CONTRAINDICATIONS
for MPFL Reconstruction

15. Permanently dislocated patella
Habitual dislocation of patella
 Usually due to a host of factors, including both bony and
soft tissue components.
 Rotational and coronal plane deformities of the femur and
tibia may need to be addressed in these cases in skeletal
maturity.
 MPFL laxity is a result and not a cause of such an
extreme alteration of the extensor mechanism.
CONTRAINDICATIONS
for MPFL Reconstruction

16. Significant patellar malalignment with an
increased Q angle [tibial tubercle to trochlear
groove distance (TTTG) greater than 15 mm]
Severe trochlear dysplasia (Dejour type B or C)
Significant patellofemoral degenerative
changes (grade III–IV)
CONTRAINDICATIONS
for MPFL Reconstruction

17. SURGICAL STEPS
 Examination under anaesthesia (EUA)
 Diagnostic Arthroscopy:
Superolateral portal
 Graft Harvest & preparation
 Incission 1: on medial side patella
 Incission 2: on femoral fixation site
 Patellar side fixation
 Graft passage from incision 1 to 2
 Femoral side fixation
 Appropriate tensioning

18. GRAFT SOURCE
 Gracilis (G): stiffness closer to MPFL
 Semitendinous (ST)
 Medial patellar tendon (PT)
 Adductor tendon (AMT)
 Quadriceps tendon (QT)
 Allografts
 Artificial tendons
 One end of the graft may be left attached; ex: ST tibial
attachment, AMT femoral attachment, QT patellar
attachment

19. MPFL tendon graft reconstruction
technique alternatives
 Tunnel graft into medial patella (Fithian, Erasmus)
 Suture anchors and loop fixation at medial patella
(Farr and Schepsis)
 Loop graft around adductor tendon insertion
(Arendt)
 Patella tunnel fixation (Nomura. Ochi)
 Adductor tendon graft (Teitge)
 Suture graft under and through VMO and also into
quadriceps tendon (Fulkerson)

20. QUADRICEPS TENDON
GRAFT
ADDUCTOR TENDON
GRAFT

21. FIXATION ON PATELLA
 Drill hole: Transverse /
Longitudinal
 Anchor
 Endobutton
 Suture: basket weave, VMO
sling, in bony trough
 Screw

22. GRAFT PASSAGE
 Graft is passed
extracapsularly from
incision 1 to incision 2.

23. FIXATION ON FEMUR
 Screw
 Suture
 Bone plug Staple
Reference:
Anatomic:
1. from the medial femoral epicondyle, 10
mm proximal and 2 mm posterior
2. from the adductor tubercle, 4 mm
distal and 2 mm anterior.
Flouroscopic:
On true lateral view of the knee.
Femoral fixation point is the most critical step

24. Schottle’s point
A line is drawn extending distally from
the posterior femoral cortex (line 3).
Two lines are drawn perpendicular to
line 3, the first intersecting the point
where the margin of the medial
condyle meets the posterior cortex
(line 1) and the second intersecting
the most posterior point of
Blumensaat’s line (line 2).
A circle of 5-mm diameter is drawn
contacting the line drawn from the
posterior cortex. The MPFL femoral
insertion should fall within this
circle.

25.  Place the pin at Schottle’s point.
 Drill the beath pin to lateral side ( more anterior and
proximally)
 Drill 4mm tunnel through; dilate according to graft size
and length ( usually 25mm long, 6 mm diameter)
 Pass suture on beath pin to lateral side
 Pull the graft ends in to the tunnel.
 Put the nitenol wire for screw insertion before whole
graft goes in; otherwise finding the tunnel to put screw
will be difficult.
 Put appropriate size screw flush to the cortex.

26. APPROPRIATE TENSIONING
 The ideal tension at the time of fixation of the graft
is unknown.
 The ligament functions as a check rein in early flexion
(0 to 30 degrees) and is therefore under the greatest
tension in this range of knee flexion. It is logical to fix
the graft with the knee at 30 to 40 degrees flexion.
 The patella should not be pulled medially by the
reconstructed ligament but lateral translation
beyond the lateral margin of the trochlear
should be prevented.

27.  The tension of the graft can be adjusted to achieve
this balance prior to fixation. Cycling of the knee
through flexion and extension prior to fixation may
help reduce subsequent creep in the construct.
 Excessive tension in flexion can lead to painful
restriction of knee flexion and articular cartilage
overload in the medial patellofemoral compartment.

28. Restore normal tracking after
MPFL restoration
 Patella should enter trochlea from slightly lateral in
extension and become centered by 15-20 degrees
knee flexion - Verify arthroscopically.
 NEVER MEDIAL

29. PRE & POST OP ARTHROSCPY

30. Skeletally Immature Patients
 Modify femoral side fixation: Don’t create bone
tunnels or dissect the periosteum in the region of the
distal femoral physeal plate.
 Adductor magnus tendon transfer
 Adductor sling technique
 Medial collateral ligament sling technique
 Combined MPFL and MPTL reconstruction

33. MPFL + MTPL RECONSTRUCTION

34. REHABILITATION
 Most of the published series have described a period of
restricted range of motion using a knee immobilizer or
a hinged brace for from 2 to 6 weeks.
 The range of motion is limited to 0 to 60 degrees.
 Weight-bearing status also varies considerably ,
ranging from minimal to full weight bearing.
 Bony fixation: Full ROM and full weight bearing are
allowed within the limits of comfort.
 Soft tissue fixation: some limitation of range of motion
and reduced weight bearing may be appropriate.

35.  Closed kinetic chain quadriceps strengthening be
introduced from between 3 and 6 weeks
 Controlled open kinetic strengthening from 3
months.
 Return to noncontact sports, with a resumption of
contact sports in 4 to 6 months, depending on
individual strength, agility, and confidence
REHABILITATION

36. COMPLICATIONS
Pain and stiffness:
 Transient: due to intervention on the highly innervated
medial aspect of the knee.
 Immediate: adhesion formation and a persisting loss of
flexion
 An important cause of postoperative pain and/or stiffness is
inappropriate positioning of the graft.
 Graft tight in flexion: anteromedial pain; restriction of
flexion; increase in the force on the articular surface of the
medial patellofemoral compartment.
 MUA if ROM < 90 degree in 6 weeks.

37.  Prominence of fixation hardware on the medial
aspect of the medial femoral condyle: local irritation and
potentially restrict motion
 Patellar fracture: usually relates to the use of bone
tunnels; penetration of the anterior cortex
 Recurrent lateral patellar dislocation:
predisposing factors such as patellar alta, trochlear
dysplasia, and lateralization of the tibial tuberosity, as well
as the overall alignment of the lower limb
 Infection
 Hematoma formation
 Graft site morbidity
COMPLICATIONS