Correcting Varus Deformity of the Knee in Total Knee Replacement

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Transcript of Correcting Varus Deformity of the Knee in Total Knee Replacement

Dr Vaibhav BagariaConsultant Joint Replacement & Sports Surgeon

Sir HN Reliance Foundation HospitalMumbai, India

THE VARUS KNEE

Welcome you all!

Simplifying Complexities

Varus KneeUnderstanding Anatomy

Classification

Soft Tissue Management

Bone Management

Tips Tricks and Traps

Medial Structures

MCL Attachments

Defining Varus

Maquet Line

Load Bearing Axis, Passes from centre of

Femoral head to Centre of Talus

Classification

Intraarticular

Metaphyseal

PAGODA deformity

Extra articular

Algorithmic approach

Think in terms of anatomy & Classify

Decide in terms of Soft tissue & Bone deformity

Execute with tips tricks and traps of special techniques.

Basic TenetsPreoperative Plan

Assess & Classify

Medial Release

Osteophyetctomy

Metaphysical Bumpectomy

Quadrant of deformity & Bone Loss management

Avoid Over release

Medial releases

A sequential release is performed until the medial structures reach a length equalizing that of the lateral structures.

Create a Medial Sleeve - medial parapatellar approach is preferred.

Creating Medial SleeveThe periosteal elevator is passed deep to the superficial MCL

Elevation should start 3 – 4 cm from the medial tibial plateau where the tibial metaphysis merges with the diaphysis

Bent Homan is inserted to create the sleeve

Creating Medial Sleeve

Order of Medial ReleaseDeep MCL

Posterior capsule

Superficial MCL

Posterior oblique ligament

Semimembranosous tendon

Pes tendon

Popliteus tendon

Medial Release

Semi Membranous release

Posterior Oblique Lig

Osteophyte removal

Remove all osteophytes from Femur & Tibia as they can tent the medial soft tissue sleeve & shorten the MCL

Osteophyte RemovalRemember to check the Posterior femoral condyle and Posteromedial tibia -> as they tighten extension gap.

Cruciate's

For severe deformities- it may be better to use PS type Knees

PCL may prevent complete correction

Non functioning PCL with CR knees —> loss of roll back functioning —> anterior opening and loosening

PCL

Posterior Release15mm or ¾ “ osteotome is used to release the posterior capsule and remove the osteophytes.

By doing this maneuver not only the flexion deformity is corrected, it also releases the medial head of gastrocnemius improving the varus deformity medially

Check the Gaps

Shift & ResectIn case of severe deformities where the gap is still not balanced, it may be a good idea to undersize and laterlize the tibia and remove the medial sclerotic bone.

After the cuts, an undersized trial tibial implant is placed & medial boundaries of the implant are marked with methylene blue. Excess bone removed with saw or an osteotome

Shift And Resect

Shift & Resect

Shift & Resect

Pie Crusting

lengthen soft tissue under tension

use 16 G needle

Remember AF PE ( Atrial Fib - Pulmonary Embolism) Mnemonic

Responsible Structures

Dealing - Residual laxityLateral laxity post balancing can be an issue

IT band is dynamic stabiliser

Medial release can be increased and thicker poly can be used

LCL advancement is an alternative

Take HomeAssess & Plan

Create Medial Sleeve

Do complete osteophtectomy & lumpectomy

Sequential Release

Shift & Resect

Pie Crust