Knee recon 2018 deiary kader post grad

POSTGRAD ORTH Deiary Kader
SPORTS INJURIES/ KNEE
FRCS(Tr&Orth) Revision Course
Professor Deiary F Kader
Knee Surgeon
SW London Elective Orthopaedic Centre
Epsom & St Helier University Hospitals
Sport and Exercise Sciences, Northumbria University
ICRC Specialist Surgeon (Geneva)
KNEE Recon

PLAN
1. Osteotomy around the knee
2. Uni compartmental Knee
3. TKR
4. PFJ OA
5. Revision TKR

Candidate’s questions ?
• Which TKR and why? How to choose knee prosthesis?
• principles of PFJR?
• principles of osteotomy angel measurements
• KM survival of TKR • Biomechanics of TKR
• Principles of knee bracing and callipers and condition which they work best
• Easy way to remember how to answer flexion extension gab balance
• When to operate for PFJ if at all
• TKR in Jehovah's witness
• Catastrophic wear in TKR
• Evidence based non operative treatment of OA —Post operative Mx of TKR
• The role of computer navigation in TKR
• Coronal plane sequential ligament release in TKR
• Osteotomy cut off age. Uni knees indications
• Do you resurface the patella?
• How does changing slop in osteotomy affect load transmission?
• Which osteotomy open or close
• PCL retaining or substituting and why
• Why TKR have different implant materials in the femur and tibia
• Prevention of catastrophic wear mean
• What are the technical difficulties in converting Uni to TKR?
• Periprosthatic fracture after TKR approach and management
• Poly difference in TKR and THR • The role of lateral facetectomy in patella arthritis

45 Y
Male
Bricklayer

Evidence based
None-operative
Treatment for OA?

OA Nonoperative treatment
Evidence
Weight loss
Exercise
Patient education
Analgesia, (NSAIDs)
Bracing
Intra-articular (IA) injections. Cochrane reviews
Steroids (better than placebo but not longer than 4wks)
HA more prolonged effect than steroids

Proximal Tibia (HTO)
or
Distal Femur Osteotomy

Osteotomy plan
Angle measurements
Principles
Planning osteotomy

Overcorrection of 3º–5º above the 6º–7º normal valgus angle
62.5% across tibial plateau from medial side

Mechanical Axis of the Lower Limb
Mechanical axis of
the lower limb
4-8mm medial

Mechanical Axis deviation MAD

33%
20
5%

Double Varus
1- Varus alignment
Progressive medial joint narrowing
2- Lateral opening
LCL laxity
>5 mm laxity ( stress radiograph)
Varus thrust

Triple Varus
Varus alignment
Posterolateral corner laxity
Increased Ext-Rotation
Hyperextension
Lateral opening
Varus recurvatum
deformity

Osteotomy for arthritis of the knee
Aims of valgus osteotomy
Unload the medial compartment
Unloading any ligament reconstruction
in patients with a varus thrust
To change the tibial slope in order to
reduce translational forces and
improve AP instability

Compensating for
Abnormal AP Laxity
ACL Rupture PCL Rupture
Usually by CWHTO Usually by OWHTO

Who is the IDEAL candidate
for HTO?

Proximal or High Tibial Osteotomy (HTO) 
The IDEAL candidate for HTO
Age <65 years
Isolated medial OA/Intact Ligaments
Non-Smoker
BMI<30
Almost Full ROM >120°
Less than 5° FFD knee
Patients should be
Able to use crutches
Have no major varicose veins
No peripheral vascular disease

The International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine

Osteotomy
vs
Unicompartmental replacement?

45 Y Male Bricklayer
Vs
58 Y old Female manager

Age
Sex
Activity level
ligament stability
Deformity

Which Osteotomy
Open or Closed?

Lateral closed-wedge high tibial osteotomies
have been the treatment of choice since 1965 
(Coventry, 1965).

Fibular osteotomy, Separating tibiofibular joint
Contracture of the patellar tendon, patellar baja
leg shortening
Nerve injuries
Varus laxity (loose LCL)
TKR is harder
High Tibial Osteotomy with a Calibrated Osteotomy Guide, Rigid Internal Fixation, and
Early Motion. Long-Term Follow-up*
ANNETTE BILLINGS, M.D.†; DAVID F. SCOTT, M.D.‡; MARCELO P. CAMARGO, M.D.§; AARON A.
HOFMANN, M.D.§, SALT LAKE CITY, UTAHJ
Bone Joint Surg Am, 2000 Jan
Closed wedge HTO  
Disadvantages

OPEN Wedge HTO 1987
The open-wedge high tibial osteotomy gained
recognition after the encouraging reports of
(Hernigou et al., 1987).
Wedges of bone that were obtained from the iliac
crest were inserted into the defect

Open W HTO

Open Wedge HTO  
Advantages 
Easier to adjust correction angle
Preserves bone stock (subsequent TKR easier)
Makes MCL tightening easier
Allows LCL or posterolateral -Reconstruction
No risk to peroneal nerve
Less dissection?

Open wedge HTO  
Disadvantages
Requires a bone graft (substitute, autograft, Allo)
Increased incidence of non-union and delayed un
Large correction may affect leg lengthening
Loss of fixation and recurrence of varus deformity
Worsens patella Baja

O W HTO

RCT 92 pts and 6 years FU
OW-HTO vs CW-HTO
More Complications in open WHTO & more conversion to TKR in closed WHTO
SEPT 2014

Distal Femur Osteotomy for Valgus
Malalignment

Coventry report 
Outcome
5-year survival of 87%
10-year survival of 66%
However the 5-year survival was reduced
to 38% if under-corrected or overweight

What are the
Biomechanical aims of
TKR?

The Primary Aim of TKR
Restoring neutral mechanical axis of 0 (+/- 3º)
Balancing the flexion/extension gap (ER of FC)
Joint line perpendicular to the Mech axis
Preserving the joint line height
Balancing Ligaments ( 2-3 mm play)
Restoring normal joint alignment and Q angle

Which knee
replacement and why?

Constraint ladder in
implant design

Constraint ladder in implant design
PCL-retaining (cruciate-retaining, or CR)
Rotating platform
PCL-substituting or posterior-stabilised
Unlinked constrained condylar CCK/ VVC
Linked, constrained condylar implant
(rotating-hinge knee, RHK).

 
 
PCL retaining or
substituting and
why

PS or CR

PCL retaining (CR)

PCL retaining (CR)
Provides least constraint
Less forces at the interface
Preserves proprioceptive fibres (intact PCL)
Greater stability during stair climbing
(quadriceps strength)
Less risk of condylar fracture

PCL retaining (CR) 2
Fewer patella complications
Preserve bone stock on the femoral side
Better kinematics
Avoids the tibial post–cam impingement
Ease of management of supracondylar
fracture (plate/nail)

PCL retaining (CR)
Disadvantages
Less conforming surfaces to allow roll-back
Slide/shear stress causes poly delamination
Technically difficult to balance
Late PCL dysfunction

GII PS + Pat

Indications for PCL Sacrificing Implants
Previous patellectomy
Rheumatoid arthritis
Stiff knee in post-traumatic arthritis
Previous high tibial osteotomy (HTO)
Large deformity, over-released PCL

PCL substitution/sacrificing
Advantages
PCL histologically and kinematically abnormal
The cam-post mechanism improves AP stability
Provides a degree of VVC
Conforming surfaces allowing roll-back
No component slide

Advantages
Higher degree of flexion
Less joint line sensitive (Restored within 8-9mm, Figgie)
Congruent joint surfaces reduces wear
Facilitates deformity correction
Superior and more reproducible kinematics
Technically easier than CR

Disadvantages
High stresses at fixation interface
Femoral bone loss/fracture
Tibial peg increases wear
Post dislocation
3X greater joint line alteration than CR
Patella clunk/ crunch syndrome

Summary
Both CR & PS knees work very well
Long term outcome comparable
One design wont fit all
PS knees outcome is more predictable
We should be able to do both when it is
indicated

 
 
Coronal plane
sequential ligament
release in TKR

Knee Ligaments
Lateral Complex
ITB
LCL
Popliteus
Biceps Femoris
Central Complex
ACL
PCL
Med Menx
Lat Menx
Medial Complex
MCL
POL
Capsule
Semi-Memb
Pes anserinus

H Schroeder-Boersch
Medial Ligament Restraint 
Range of Ligament restraint medial knee 

Ligament restraint Lateral knee
H Schroeder-Boersch

PCL 0º-120º more in flexion
It is “a central stabiliser”
15mm
PCL insertion
15mm

LCL 0º-120º & Popliteus 30º-120º

Medial release for varus knee
Osteophytes excision
Deep MCL to posteromedial corner
Semimembranosus aponeurosis
Superficial MCL
PCL
Pes anserinus insertion

Pie-Crusting Technique
Extension
Osteophytes excision
Deep MCL to posteromedial corner
Flexion

What are the problems
associated with valgus
knees

Valgus knee
Multiple problems associated with valgus knees
Soft-tissue abnormality
Bony deficiencies — acquired or pre-existing
Patella subluxation
Lateral capsule and ligament contracture
PCL dysfunctional in severe valgus
Distal femoral rotational deformity with externally
rotated epicondylar axis up to 10°.

Soft-tissue release in valgus knees
Osteophyte excision
Lateral patellofemoral ligament (LPFL) release
Release posterolateral capsule off the tibia
Sacrifice PCL in moderate-severe valgus.
Flexion and extension tightness
Release (or pie-crust) lateral collateral ligament (LCL) from
the femur.
Flexion tightness
Release Popliteus
Extension tightness
Release (or pie-crust) the iliotibial band at Gerdy’s tubercle

Valgus Knee
Posterior capsuleLCL release
Flexion and extension tightness

Tight in FlexionTight in Extension
Lateral collateral release for valgus knee

Easy way to
remember
Gap balancing

Flexion & Extension gaps
Tibial Cut Flexion and extension gaps
Distal femur Extension Gap
Posterior osteophytes Extension Gap
Posterior condyles Flexion Gap
Tibial slope Flexion Gap
Implant size Flexion Gap
PCL Excision Flexion Gap
Asymmetric Extension Gap soft tissue or tibia

Balancing Flexion and Extension Gaps

 
 
What are the technical
difficulties in converting
Uni to TKR?

50% of Uni knees had a significant bone defect

Post op Mx of TKR

Pain Control
1) Patient education 
2) Preemptive analgesics 
3) Epidural analgesia 
4) Peripheral nerve block: Add/femoral nerve block 
5) Periarticular injection 
6) Patient-controlled analgesia (PCA)? 
7) Oral analgesics

Consenting/complications
✦ Infection
✦ DVT
✦ Pulmonary embolism
✦ CVA or MI
✦ Skin numbness
✦ Implant longevity
✦ Fracture
✦ Neurovascular injury
✦ Delayed wound
healing
✦ Extensor mechanism
injury
✦ Death
✦ Rehab-Golden 2
weeks
✦ Smoking
✦ Pain postop
✦ Skin problems
✦ Remote infection
✦ Nickel allergy
✦ Blood transfusion
Consent this patient for TKR

Aseptic complications after TKR
Wound healing
Extensor Mechanism complications
Stiffness
Periprosthetic fractures
Loosening
Neurologic injuries
Vascular injuries
Thromboembolic disease

 
 
Poly difference in
TKR and THR

Processing methods for
XLPE acetabular liner
and tibial insert for
total hip and knee
arthroplasty

KNEE
TKR is less constrained
less conformed
high contact stresss
Sheering force
subjected to fatigue wear (delamination)

Highly Cross Linked Polyethylene
(XLPE)
Cross-linking Dramatically reduces
volumetric wear BUT
1. Reduces toughness
2. Decrease the ultimate tensile strength
3. Decrease resistance to fatigue crack
propagation

Technical Considerations in TKR
How would you determine the
rotation of the femoral component?

Femoral Component
What is the optimal external rotation ?
Suggesting that 2–5° of external rotation is the optimal position
referenced oﬀ the posterior condylar axis
Kim et al. (2014)

Rotational alignment of the femoral component  
Anatomical landmarks for reference:
Epicondylar axis
Posterior condylar axis
Anteroposterior axis ( Whiteside’s line)
The ant cortex of the femur

Surgical
Anatomic POSTGRAD ORTH Deiary Kader

1-The epicondylar axis
Problems
Difficult to identify, peaks are often obscured
by the everted patella Overlying collateral
ligaments and adipose tissue.
Misuse of the surgical epicondylar axis rather
than the Anatomic one

2-The posterior condylar axis
Problems
Inaccurate in severe arthritis
Anatomy of the femur varies
Gender variation
Valgus knee hypoplastic LFC
Varus knee MFC larger

3-Anteroposterior (AP) axis
The line deepest part of the trochlear to the Centre of the
intercondylar notch posteriorly
Difficult to Identification
In trochlear dysplasia or destructive arthritis
knees with significant varus or valgus deformity
Whiteside’s line

4- The Anterior Femoral Cortical Line
Dr Mervyn Cross

Tibial Tray Rotation
Medial border of the tib tub
Medial 1/3 of the tibial
tubercle
Middle of the tibial tubercle
Patellar tendon
PCL attachment
Transverse axis of the tibia
Posterior condylar line
(tibia)
Mid-sulcus of the tibial spine
Malleolar axis
The second metatarsal
Reference from the femur

What if the FC internally rotated
•Asymmetric flexion gap
•Shift into valgus alignment with flexion
•Increase in Q angle
•Patella mal-tracking/Instability
•Severe patellar wear if resurfaced
•Asymmetric tibial component load

 
The role of computer navigation
in TKR

prospectively compared the results of 520 patients with
osteoarthritis who underwent computer-navigated total knee
arthroplasty for one knee and conventional total knee arthroplasty
for the other.
Results demonstrated no difference in
clinical function or alignment and
survivorship of the components
RCT 520 pts Navigated vs Conventional

Titanium or Cobalt Chrome
for Tibial component?

Cobalt Chrome Property Titanium
Yes Fatigue resistance Better
No Stress Shielding Much Better
220 GPa Elastic modulus 110 GPa
Excellent Bearing surface Never unless treated
Resistant Wear Poor characteristics
less Scratch sensitive Scratch sensitive
Poly (osteolysis) Debris Metallic debris
(toxic)

Materials in TKR
Material Elastic Modulus
Stiffness
316L Stainless Steel 230 GPa
Cobalt-Chrome alloy 220 Giga Pascal
Ti6Al4V 110 GPa
Cortical Bone 21 GPa
Trabecular Bone 15 GPa
PMMA Cement 4 GPa

Ti or CoCr for tibia
Titanium oxide and Titanium alloys have great corrosion
resistance, inert biomaterial, fast bone bonding and reduce
stress shielding
Titanium alloy knees generated significantly more metallic debris
more toxic to the surrounding tissue
CoCr knees more polyethylene debris and more likely to release
inflammatory cytokines causing osteolysis

Principles of PFJR

PFJ OA
kneeling, squatting, climbing stairs, and
getting up from a low chair.
More subtle than knee OA
Swelling para-patella
Crepitus anterior knee

PFJ OA
Non-operative treatment
Anti-inflammatory medications
Activity modification
Quadriceps strengthening
Bracing,
Steroid injections
Viscosupplement

PFJ OA
PFJ replacement or TKR?

PFJ OA
PFJ replacement or TKR?
1. Age
2. Other compartments
3. Implant failure rate

PFJR
Revision rate 9% in 5 years
revision rate is 19% in 10 years
why?
Failure to regard as a Soft tissue procedure
Maltracking
Catching
Subluxations
Implant design

Priciples
Understanding the pathology and Dx
Is there instability?
Meticulous surgical technique
Soft tissue balance/lateral release
External rotation of the trochlea
Avoid over/understuffing the patella
Implant design use on-lay not inlay
AVON Stryker
FPV Vialli Wright medical
Journey by S&N

Would you resurface
the Patella during TKR?

Patella

Patella resurfacing debate
For
Reduces anterior knee pain
Improves strength in flexion stair descent
Less likely to revise the knee for AKP
Secondary resurfacing results are inferior
Better results in RA

Patella resurfacing debate
Against
No difference in outcome
Increase wear particles
Early technical complications
Long-term patellar fracture

Patellofemoral maltracking
DO NOT
Overstuff the patella.
Oversize the femoral component
Internally rotate of the tibial component
(increases the Q angle)
Avoid an excessive valgus angle
Avoid raising the joint line
Avoid inferior placement of the patella component

Indications for
selective patella replacement:  
Advanced osteoarthritic patella
Rheumatoid arthritis
Preoperative patellofemoral pain
Obese patients
Overweight females
Chondrocalcinosis

Prospective, randomised, double-blinded study of 350 TKR
with selective patellar resurfacing
Follow-up of 7.8 years demonstrated that satisfaction was
higher in patients with a resurfaced patella.
Followed for at least 10 years, no significant difference was
found. No difference was found in KSS scores,
survivorship and no complications of resurfacing were
identified.
The vast majority of patients with remaining
patellar articular cartilage
do very well with TKA regardless of patellar resurfacing.

Patella resurfacing in TKR  
(Randomised trial)
Barrack et al Sept 2001 JBJSA
118 TKR F/U >five years
No difference in outcome
Ant knee pain relate to
Component design
Surgical technique

Patella resurfacing in TKR  
(Randomised trial)
Wood et al Feb 2002 JBJSA
220 TKR mean F/U 48 months
Superior results in term of
Stair descent
Ant knee pain 16 % compared to 31%
10 % had revision in the resurfacing gp

14 Causes for Patellar problems
7 in the Femur: IR, ER, medial, Valgus, Ant,
Post, oversized
4 in the Tibia: IR, Medial, Valgus, Ant
3 in the Patella: under-resection, Over-
resection, lateral

 
 
Peri-prosthatic fracture
after TKR approach and
management

88 Y lady from a nursing home had knee revision 8 years ago

75 Y lady lives alone. knee revision 5 years ago was doing well

Distal Femur Replacement

Mal-Alignment

Common causes of
Painful knee arthroplasty
• Infection
• Aseptic loosening
• Instability
• Stiffness
• Malrotation
• Malalignment
• Patellar pain
• Patellar dislocation
• Extensor mechanism Inj
• Incompetent MCL
• Periprosthetic fracture
• Implant breakage
• CRPS
• Hip or spine pathology
• Unexplained pain (1/300)

Indications for Revision TKA
• Aseptic loosening (30-40%)
• Infection (22%)
• Pain (10%)
• Mal-alignment 7-10%

The primary goal of revision TKR
To restore knee alignment and stability
through a full range of movement
Re-establish the native joint line
Well-fixed implants
Appropriate soft tissue balancing ensures
stability
Avoids intra-operative extensor mechanism
complications

Management
History &
Examination

Investigations
Plain weight-bearing X-ray
Bloods (including WCC, ESR and CRP – IL-6 (expensive)
in specialist units
Knee aspiration
Fluoroscopic alignment check
CT scan to check rotation and long leg films to assess the
overall alignment
Bone scan (not helpful until a year after the index
procedure), white cell-labelled bone scan
SPECT-CT has also been a novel imaging option to detect
loosening / infection and highlight areas of maximal
activity.
The Synovasure™ Alpha Defensin Test

AAOS Clinical guideline for Dx infection 2010
The working group strongly recommended:
Testing ESR and CRP
Joint aspiration
The use of intraoperative frozen sections
Obtaining multiple intraoperative cultures ( at least 3 but no
more than 6 using different instrument for each sample and
from different areas)
• Against initiating antibiotic treatment until after cultures
• Against the use of intraoperative Gram stain
Nuclear imaging was weakly recommended as an option

What is the Definition of
Peri-prosthetic joint Infection?
What is the AAOS Clinical guideline for Dx
infection 2010

What is the Definition of
Peri-prosthetic joint Infection
International Consensus Meeting in 2013 as:
Musculoskeletal Infection Society
A sinus tract communicating with the joint
OR
2 positive cultures with identical organisms
OR
3-4 of the following minor criteria:
Elevated CRP and ESR
Single positive culture
Elevated synovial fluid WCC —1,100 to 4,000 cells/µL
Elevated synovial fluid PMN 64%-69%
Presence of purulence in the affected joint
Isolation of a microorganism in one culture of tissue or fluid
Greater than 5 neutrophils per high-power field in five high-power fields
observed from histology at 400 times magnification

Infection
Revision for
Infection (22%)

Commonly used CCK in UK
PFC Sigma
TC3 (DePuy)
Triathlon TS
(Stryker)
Legion
Smith &
Nephew
Vanguard SSK
(Biomet)
NexGen
(Zimmer)

CCK progression to Hinged knee
One should be aware of
inter species
compatibility

Bone defects

Metaphyseal Sleeves & Cones

Trabecular Metal Cones

 
 
TKR in Jehovah's witness

JEHOVAH’S WITNESSES
RCS Professional and Clinical Standards November 2016
Pre-admission patient optimisation
• Essential blood samples, FBC, U&Es, LFTs, Clotting screen and fibrinogen, B12 and folate and iron
studies
• General health optimisation
• Erythropoietin Hb <13g/dL M and Hb ≤ 12g/dL
• Erythropoietin ineffective in patients with iron, B12 or folate deficiency
Intraoperative considerations – blood conservation strategies
• Consider minimal invasive
• Hypotensive anaesthesia and even controled hypothermia
• Cell Salvage
• Coagulation stimulants such as Tranexamic acid and factors (VIIa, VIII, IX) and desmopressin
• Haemostatic aids: diathermy and radiofrequency ablation
• Regional anaesthesia with the consultant anaesthetist
Postoperative considerations
• Monitor and minimise blood loss postoperatively
• Monitor and avoid sepsis
• Consider postoperative EPO and/or Iron/B12 replacements
• Where appropriate and acceptable to the patient, use blood salvage from drains (cell saver)

Knee Arthrodesis 
Indications
• Failed TKR
• Uncontrollable sepsis/ Resistant organisms
• Neuropathic joint
• Disruption of extensor mechanism
• Poor soft-tissue envelope
• Systemically immunocompromised
• Post-traumatic OA (heavy manual labourer)?

Contraindications
• Bilateral knee disease
• Ipsilateral ankle or hip disease
• Ipsilateral hip arthrodesis
• Severe segmental bone loss
• Contralateral limb amputation.

Optimal position for knee fusion 
• 7°–10° of external rotation
• Slight valgus
• 10°–20° of flexion
• The above may be easier to achieve with
external fixator rather than IM nail.

Techniques
Intramedullary arthrodesis
External fixation
Plate fixation

Complications
Non-union
Malunion
Delayed union
Recurrent infection

Thank You

Knee recon 2018 deiary kader post grad

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