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3. surgery

Patellofemoral Compartment:
Osteotomy Planning and Treatment
Algorithm
Jack Farr, M.D.
Cartilage Restoration Center of Indiana
OrthoIndy Knee Care Institute
Indianapolis, IN
Financial Disclosures
Royalties
• Arthrex
• DePuy/Synthes
Consulting
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Arthrex
Advanced Biosurfaces
DePuy (JNJ company)
DePuy/Mitek (JNJ company)
Eli Lilly
MedShape
Moximed
NuTech
Genzyme
Osiris
RTI
Regenerative Biologics
SBM
Sanofi (Prior Genzyme)
Regeneration Technologies
Zimmer
Step One
Relate the Pathology to the
Symptoms:
Pain and/or Instability
Classifications to aid in Treatment
Type of Instability (High vs Low Energy)
• Morphology : Normal vs. “Dysplastic”
• Traumatic vs. Atraumatic
• Fulkerson Alignment Classification
• TT-TG and Caton-Deschamps Ratio
• Soft Tissue Envelope (MPFL/ Lateral
Retinaculum)
Site of Pain
• Regional Chondrosis Mapping
Importance of Chondrosis Site:
Pidoriano & Fulkerson Classification
Proximal
Medial
Lateral
AMZ best for
distal lateral
A
B
C
D
Type I is articular injury to the inferior pole
Type II is articular injury to the lateral facet
Type III is articular injury to the medial facet
Type IV is articular injury to the proximal pole
(Type IVa) or a panpatellar injury (Type IVb).
Importance of Mapping
• Inferior Pole and Lateral Facet:
87% G/E
• Medial Facet:
55% G/E
• Proximal Pole and Diffuse:
20% GE
• Concomitant Central Trochlear Involvement: All Poor
Pidoriano and Fulkerson, 1997
Step Two
Identify Why Is There Pain?
Assigning “Pathology” to Chondrosis:
Diagnosis by Exclusion
Articular cartilage is aneural
Pain therefore originates from:
• Soft tissue (Synovium, Capsule, Tendons and
Ligaments)
• Nerves (Local or Remote, e.g., saphenous,
neuroma)
• Bone (Local or Remote, subchondral BML,
referred hip)
Step Three
Right Surgery for the Right Patient:
Patient Specific, Demand Matching
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Treat patients with pain on the basis of the
mechanically identifiable factors and
associated chondral defects
Exclude ill-defined pain, CRPS, debilitation and
those exceeding their “Scott Dye Envelope of
Function”
Step Four
Applying the Specific Surgery
Tibial Tuberosity Osteotomy
• TT-TG distance > 20mm—BUT DON’T STOP THERE
• Assess Femoral/Tibial rotational abnormalities
e.g., Increased femoral anteversion: CT (Teitge); MRI
(Noyes) to assess hip/knee/ankle rotation
Tibial TuberosityTrochlear Groove Distance
13 mm: Dejour. Knee Surg Sp Tra Arthr, 1994
10 mm: Pandit. Int Orthop, 2011
CT = MRI: Schoettle. Knee 2006
Varies with remeasurement mean 3.2 mm: Lustiq. Rev
Chir Ortho Repar App Mot, 2006
• PT to TT varies to 4.2 mm; PT less variable Wilcox. COOR,
2012
• May be altered when alta present; Caton. Int Orth 2010
• MRI ≠ CT Camp, Levy, Dahm et al AJSM 2013
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Tibial Tuberosity-Trochlear Groove
Distance
• Cannot estimate clinically: Shakespeare. Knee,
2005
• Q angle and TT-TG poorly coorelate: Cooney.
Knee Surg Sport Traum Arthr 2012
• Difficult to impossible to measure with
dysplasia
If Marked Dysplasia,
There is no TG
TT-Posterior Cruciate Ligament
Seitlinger et al AJSM 2012
• Control 18.4 mm
95% < 24 mm
• Instability Patients
Seitlinger AJSM 2012
38% > 24 mm
57% with TT-TG > 20 had TT-PCL > 24 mm
43% with TT-TG > 20 had TT-PCL < 24 mm (could
these have femoral based abnormality)
Take Away
• All radiographic assessments need validating
per meta-analysis of 27 studies: Smith.
Skeletal Rad 2011
• Consider whole limb and local anatomy before
focusing on tuberosity position as pathological
Deciding on Tuberosity Transfer
• Degree of Anterization:
Ferrandez 10 mm Clin Ortho 1989
Ferguson 12.5 JBJS 1979
Fulkerson 15 mm AJSM 1990
• Medialization
Do NOT over-medialize—Kuroda et al 2005
Goal to normalize in range of TT-TG 10-15 mm
FEA Patient-Specific Models for TTO:
AMZ 20% mean decrease in stress—BUT Variable
Preop
Maquet 15
AMZ 8/8
AMZ 15/8
Maquet 20
AMZ 15/8
Uniform thickness
Cohen et al AJSM 2003
Planning Tuberosity Transfer
• Preop Planning: Knee Specific
• Steepest slope approx. 60 degrees
• Applying Trigonometry to a constant elevation of
15mm:
60 degree slope & elevation 15 = 8.7 mm medialization
Example of Typical Excessive TT-TG of 22 treated with:
60 degree slope or 8.7 = 13.3 post op TT-TG
Medialization with Anterization
15mm
anteriorization
8.7 medialization
60 degrees
AMZ-Indications
• TT-TG - abnormally elevated and distal lateral
chondrosis of the patella without trochlear
involvement
• Very steep AMZ in severe lateral PF compartment
overload (excessive lateral compression/ tilt)
• Straight anterization when TT-TG is within normal
limits and the goal is to decrease PF forces (Fulkerson
osteotomy modified for straight anterization).
AMZ-Contraindications
• Proximal pole, medial, panpatellar chondrosis
or concomitant chondrosis of the trochlea
• TT-TG within normal limits (Straight
anterization is an option in this setting)
• Pain is not directly related to a biomechanical
abnormality that will be reversed by AMZ
AMZ Literature
Fulkerson JP
(11)
AMZ
AJSM 1990
30 pts12 pts
> 2 y F/U>5 y
F/U
89-93% G/E
Advance DJD
subgroup: No E;
75% G
Pidoriano AJ
(5)
AMZ
AJSM
1997
23 pts
10 F/U
87% G/E
distal/lateral
chondrosis
55% G/E medial
chondrosis
poor results with
trochlear chondrosis
Buuck D
(12)
AMZ
Op Tech
Spt Med
42 knees in 36 pts
8.2 mean F/U
86% G/E
Bellemans J
(13)
AMZ
AJSM 1997
29 patients
32 mon mean (25- 28 successful
44 mon)
Naranja RJ
(14)
Elmslie-Trillat AJSM 1996
Maquet
55 knees in 51
patients
74.2 mon (13 –
196 mon)
73-84% G/E
AMZ example:
Chronic Patellar Subluxation
Lateral Lengthening
Exposure for concomitant
patellar chondral restoration
with AMZ
IT band layer of lateral
retinaculum divided adjacent
to patella
Lateral Lengthening
A second retinacular
cut is 2 cm posterior
to the patella to allow
lateral lengthening
Anterior compartment is
reflected and the patellar
tendon is released
Creating Sloped Osteotomy
AMZ cutting block with
slope selector
Conflict of Interest Disclosure
Saw through cutting block
and tibia exiting on
retractor
Farr on Design team for the Tracker AMZ Jig System (DePuy Mitek) and T3 (Arthrex)
Alternative AMZ Jig System
Conflict of Interest Disclosure: Design Surgeons Farr, Cole, Nawab; Arthrex
Completing the Osteotomy
Saw using first cut as
captured guide
Osteotomes connect
posterior cut proximally
Steep osteotomy completed with free tuberosity pedicle
Tuberosity fixed with 2 interfragmentary screws
Anterized 15mm; medialized 7mm
Post Op Radiographs
TT Straight Medialization
Indications:
• Highly controversial
• Lyon France school of thought: Patellar alta and
trochlear dysplasia are the main problems to be
addressed for patellar instability
– Distalization of the tuberosity only
• US surgeons are divided: patellar instability is
treated with good reported results by:
– TTO alone (medialization +/- distalization)
– MPFL repair/ reconstruction alone
– MPFL surgery concomitant with TTO
Farr TTM Indications
TTO concomitant with MPFL Recon if elevated TTTG with goals of:
• Normalization of the lateral resultant vector to aid in
the PF tracking when there is minimal chondrosis
(grade 2 or less)
• To optimize PF contact area when this is static lateral
position of the patella
TTM Contraindications
• TT-TG distance is within normal limits
• Greater than grade 2 chondrosis or if the TTM
will increase loading to areas of chondrosis
TTM
Carney JR (6)
Roux-ElmslieTrillat
AJSM
2005
instability
14 pts.
3 and 26 y mean
F/U
7% unstable @ 3y7%
unstable @ 26 y54%
G/ENo radiograph F/U
Karataglis D
(7)
Modified ElmslieTrillat
Knee 2006
Instability
and/or pain
44 knees in 38
pts
40 mon mean; 18130 mon F/U
73% G/Ebetter if for
instability than pain or
Grade II or less chondrosis
Kumar A (8)
Elmslie-Trillat
Knee 2001
instability
9 pts
3 y mean F/U
No recurrent instability
Nakagawa K
(9)
Elmslie-Trillat
JBJS 2002
instability
45 knees in 39
pts
13.5 y mean F/U
13 % instabilityG/E
decreased from 91% at 45
mon to 64% at final
secondary to pain
Shelbourne
KD (10)
Modified ElmslieTrillat
AJSM
1994
34 instability 11
pain
45 knees in 40
pts
2 yr mean F/U
20% recurrent sublux, no
dislocation
Excessive lateral position of tibial tuberosity (verified
preoperatively by CT and normal axial alignment)
excessive lateral position of
tuberosity
patellar tendon released,
incision continues along
lateral border of tibial
tuberosity
Proximal axial cut just proximal to patellar tendon attachment to
tuberosity; anterior compartment musculature elevated 1.5cm
posteriorly
Coronal plane cut medial to
lateral
Angled distal-medial to
complete the 6-8cm coronal
plane osteotomy
Osteoclasis to rotate the tuberosity medially: normalize TT-TG
Tuberosity secured with two 4.5 interfragmentary screws
Distalization to treat Patellar Alta
Mayer et al. AJSM 2012
“V” shape cuts
Measure bone to be resected
allowing for saw blade kerf
Fixation followed +/- tendodesis
Neyret et al AJSM 2012
Tuberosity Distalization
Caton-Deschamps
28 mm
26mm
28 mm
36.4mm
42 mm
36.5mm
26.3mm
= 1.39
28.4mm
27.2mm
= 1.03
Proximalization to treat Patellar Infra
(NOT PI Contraction Syndrome)
Caton, Deschamps, Lerat, Dejour. Rev Chir Ortho Rep App Mot 1982
Skeletonize Tuberosity
Remove proximal expose bone
Tuberosity Proximalization
33.61 * mm
26.74 * mm
39.01
16.67
=2.34
25.40 * mm
33.61
26.74
=1.25
Straight Anteriorization
Fulkerson Modification
N/V protected with retractor
Cut to, NOT through posterior wall
Anterior to Posterior Cut
Lateral Wall Cut
Proximal and Distal Cuts
SA complete
Lateral to Medial Fixaton
Thank You