Correction of varus deformity Varus deformity: is the most common deformity of the ostearthritis knee, and multiple techniques have been described for

Correction of varus deformity

• Varus deformity: is the most common deformity

of the ostearthritis knee, and multiple techniques

have been described for its correction.

• The surgeon should understand which anatomic

structure will affect the extension and flexion

gaps so that each individual type of gap

asymmetry can be properly corrected.


• The first remove all osteophytes on the femur

and the tibia because thay can tent medial soft

tissue sleeve and effectively shorten the MCL.

• Make the initial exposure to include release of

the deep MCL off the tibia to the posteromedial

corner of the knee.


• If the extension gap is tight only medially,

release the posterior oblique ligament and

semimembranous on the tibia.

• If the flexion gap is tight, release the anterior half

of the superficial MCL and the Pes anserinous

• If the entire soft tissue sleeve is released and the

medial gap is still tight (in severe varus) consider

advancing the L.C.L


• PCL: make sure the PCL is resected before

balancing.

• Because the PCL is a secondary medial stabilizer,

take care not to release the entire soft tissue sleeve

off the tibia because it may overshoot the gap.

• Is general, less soft tissue release is needed to

balanced a varus knee once the PCL is resected.


Assess the flexion and extension gaps

A.If the gaps are tight: Release the superficial MCL

incompletely on tibia.

B.If the extension gap is tight: Release P.O.L and

semimembranous.

C.If the flexion gap is tight: Release the superficial

MCL completely and Pes.


• Bony deformity: when deformity is fixed and

nonreducible, and in late stage, some degree of

bone erosion is often present at the concave

side of the deformity, where ligament and knee

capsule are contracted.

• Significant varus or valgus malaligament on the

coronal plane is very often associated with

sagital plan and torsional deformities.


• Two points: That we must attention.

1.With significant flexion deformity, the surgeon may

need more extensile soft tissue work on the

posterior capsule and gasterocnemius insertion.

2.Extraarticular diaphyseal or metaphyseal deformity

are often associated with fixed deformity at the joint

line and possibility need to correcting the deformity

at the joint level with generous bone resection and

ligament release or a combined osteotomy.


• Pagoda: in advanced deformity, the tibial medial

platateau develops a concave pagoda shape in which

the femoral condyle is embedded, leading to a difficult

tibial dislocation maneuver that may harm the MCL.

• In these cases, we suggest violating the posterior tibial

osteophyte with a straight osteotome between tibia

and femur at 90 degree of flexion.

• In severe cases we prefer to remove the PCL and to

use a PCL substituting.

Correction of varus deformity• After a bone cuts and primary release, if some

medial residual tension remains, the distal insertion of superficial of MCL is released at least & to 10cm from the joint line.

• Alternatively, the MCL could be pie-crusted with a 16-gauge needle with multiple punctures.

• In advanced fixed varus we must select a small tibial size to lateralized it.

• This causes remove the exposed medial sclerotic bone, which is tenting the medial structures both in extension and in flexion.

Correction of valgus deformity

• Valgus deformity is common in Rheumatoid and

inflammatory arthritis and in patients with

hypoplastic lateral femoral condyle or previous

trauma or osteotomies.

• The three layer anatomy of the lateral side of the

knee joint makes its soft tissue balancing more

complex than with varus deformity.


• During exposure of a knee with valgus deformity,

take care not to compromise the medial soft tissue

sleeve.

• The first release of the lateral side and release the

lateral capsule from tibia.

• The second stage depends on whether both the

extension and flexion gaps are right. If both are tight,

release the LCL off the lateral epicondyle, taking

care to leave the insertion of the popliteus intact.


• If only the extension gap is tight: release the

iliotibial band by a Z lengthening or pie-crusting of

the band two cm above Joint line.

• Release of the posteromedial corner has been

shown to effectively increase the extension space

more than the flexion space.

• Release of the popliteus tendon will increase the

flexion gap laterally more than the extension.


• If the knee is still not balanced in full extension after

release of all three structures, release the posterior

capsule off the lateral femoral condyle. Then release

the lateral Head of gasterocnemious, if further

correction is needed.

• PCL is a medial structure and often is lengthening in

a valgus knee but sometimes is involved in the

deformity.


• If complete release of all of above structures, dose

not balanced the flexion and extension gaps,

consider advancement of the MCL.

• If the lateral flexion gap opens more than the flexion

gap, make certain, that the ”Jump height” of a

posterior stabilizing peg is not exceeded and

consider using CCK.

Correction of valgus deformity• Pie-crusting technique: Is another technique used

for soft tissue balancing in valgus knee, and allows direct lengthening of taut soft tissue under tension of the joint space.

• Multiple stabs wound are made with a scalpel blade parallel to joint line.

• There are multiple studies with good results for both valgus and varus.

• The advantage is that it leaves supporting tether and not allow a large gap opening on the lateral side of knee in extension.


• Bone deformity: Intraarticular bone deformity can

be recognized preoperatively.

• Hypoplasia: of lateral femoral condyle in valgus

knee and possible need for augmentation and

ipertrophic medial femoral condyle in varus knees

and to achieve a stable and rectangular flexion gap

must be attention.

•


• Approach: we believe it is possible to safety address

all valgus deofromities from a medial Parapatellar

approach, but some surgeons advocate the need for a

lateral approach for a directly to pathology

• For some severe cases there is need to tubercle

osteotomy.

• In these cases there is lateral capsular closure

difficulties and need to use fat pad.


• For severe cases, we suggest some degree of

overcorrection for distal cut and must select 4

degree and attention is paid to select entry point

more medial than usual.

• Tibial resection is performed perpendicular to the

mechanical axis as usual.

• AP Femoral bone resection are performed using all

available landmarks with a special focus on the

epicondyles.


• In vaglus knees because of lateral condyle

hypoplasia, requiring additional degrees of external

rotation related to the posterior condyle axis.

• Valgus knees usually are more deformed in

extension than in flexion.

• This makes the posterior capsule and the iliotibial

band the most frequently contracted structures.


• The LCL is also contracted in more than 50% of

cases and the popliteal tendon is less involved.

• Our preferred lateral release techniques is

pie-crusting techniques performed with multiple

punctures with the knee in extension and the laminar

spreader distracting the knee joint space, the

contracted structures are palapted, A no 15 small

blade is used to perform a capsular incision at the

level of the tibial bone cut off the posterior capsule.


• In severe valgus deformity recommended:

A. Use a lateral approach an pie – crusting

technique for balancing.

B. Use a constrain condylar knee

C. Use Hofaplasty technique for closure of joint

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Correction of varus deformity Varus deformity: is the most common deformity of the ostearthritis knee, and multiple techniques have been described for