Surgical Technique

ApproachRevision TKR Tibial Lysis




Always use the most lateral scar

- blood supply comes from medial aspect

- want to avoid a large lateral flap of dubious quality

- cross transverse scars at 90o

- minimum 7 cm skin bridge



- can do trial / sham incision down to capsule

- can perform skin expansion prior to surgery

- consider plastic surgical review for muscle flap

(medial gastrocnemius rotation flap)




Excise scar tissue

- recreate medial and lateral gutters

- recreate suprapatellar bursa


Patella eversion

- can just slide patella off laterally rather than evert

- put pin in tibial tuberosity to protect patella tendon insertion


Extensile exposures


1.  Quadriceps snip


2.  Quadriceps turndown


Rarely used

- risk AVN of patella


May consider if limited flexion

- lengthen quadriceps tendon


3.  Tibial tuberosity osteotomy 

- 6-10 cm long, 2 cm wide, 1 cm thick

- lateral periosteum intact / lever open laterally

- bypass osteotomy with stem

- need to wire back around the tibial stem

- place wires before definitive stem

- drill holes medially and laterally

- can use diverging screws as well


Removal of components


Remove poly

- implant specific tools


Careful removal implants to minimise bone loss

- thin, flexible osteotomes, micro-sagittal saw

- gigli saw

- can cut metal with carbide burr


Cemented femur / tibia

- separate at cement-implant interface

- remove cement later


Uncemented femur / tibia

- rarely have to cut base plate from keel (carbide burr)

- can perform TT osteotomy

- stacked osteotomes


Prepare Tibia



- sets joint line

- enables flexion extension balancing


Insert trial intramedullary stem


Find IM canal

- ream until appropriate diameter

- desired length

- place trial 

- set proximal cutting jigs off IM stem


Proximal tibial cut


Minimal tibial cut

- cut 1 - 2 mm off high side to preserve bone

- usually lateral side

- make resection for desired augment (5 or 10 mm) other condyle

- use jig


Insert trial tibia


Use offset as required

- ensures tibial component good fit on tibia

- tibial component not dependent on stem position

- ensure not internally rotated

- attach required augments


Recreate Joint line



- if rebuild tibial with augments and poly to correct joint line

- can rebuild distal and posterior femur to match


Revision TKR Severe Loss Tibial Bone StockRevision TKR Tibial Augments



- scar from meniscal remnant

- 10 mm above fibula head

- 30 mm below medial epicondyle

- use templated distance from medial epicondyle on other knee


Restore joint line with appropriate sized poly


Prepare Femur


Insert trial intramedullary stem


Find IM canal

- entry point important

- if too posterior will flex femur

- if too anterior will extend femur


Revision TKR Anterior Femoral Stem Entry


Ream until press fit

- insert desired length of stem


Distal femoral Cut


Distal cutting block on stem

- want to freshen surfaces minimally

- 1-2 mm off distal surface only

- consider distal femoral augments

- wait to trial extension gap to decide distal femoral augments


AP sizing


Posterior femoral condyles frequently deficient

- require augment posteriorly

- use anatomically sized femoral component

- template from other knee or use previous size from primary

- add augments posteriorly as


May need offset so femoral component sits on IM stem


Revision TKR Offset Femoral Stem




Trans-epicondylar axis most reliable

- posterior femoral condyles may be more deficient laterally than medially

- set correct rotation

- freshen AP and chamfer cuts




1.  Loose flexion and extension

- ensure poly thickness restores correct joint line

- increase distal and posterior femoral augments


2.  Loose flexion gap

- most common

- add posterior femoral augments

- use appropriate sized femoral implant


Revision TKR Posterior Femoral Augments


3.  Loose extension gap

- increase distal femoral augments


Distal Femoral Augment


4.  Tight flexion gap


A.  Reduce femoral distal augments / femoral component size

B.  Lower joint line by reducing poly thickness

- becomes loose in extension

- increase distal femoral augments


5.  Tight extension gap


A.  Correct joint line

- decrease distal femoral augments

B.  Joint line too high

- reduce poly to joint level

- create loose flexion gap, posterior femoral augments 


6.  Tight flexion and extension

- reduce poly thickness




Usually determine constraint after bone defects dealt with and flexion / extension gaps balanced


1.  Collaterals Intact


Posterior stabilised sufficient


Revision TKR Posterior Stabilisation APRevision TKR Posterior Stabilised Lateral.jpg


2.  MCL deficient


Option A


Young patient MCL deficient

- High Post / Condylar constrained implant

- will eventually fail if don't reconstruct MCL

- young patient use CCK as internal splint and reconstruct MCL


MCL reconstruction

- achilles tendon allograft

- semitendinosus left attached distally


Option B


Rotating hinge 

- elderly patient MCL deficient


Revison TKR Hinge APRevision TKR Hinged Lateral


TKR HingeTKR Hinge


3.  Lateral instability




1.  Femoral component malrotation


2.  ITB deficient


- brace for 3/12


3.  LCL deficient

- VVC + reconstruction

- semitendinosus / lars / allograft

- find centre of rotation on femur

- pass through drill hole in fibula






1.  > 10 mm bone remaining

- can resurface


2.  Ignore


Revision TKR Non Resurfaced PatellaRevision Patella


Patella tendon avulsion


1.  Repair

- Krackow suture secured around tibial post and washer

- staples


2.  Biological augmentation

- semitendinosus graft and gracilis

- achilles allograft


3.  Immobilise in extension for 6 weeks


Revision TKR Staple Patella Tendon Insertion