Conservative Management of Severe OA Knees with the V-VAS Orthosis

Management of SevereOA Knee

Customised Knee Orthosis

William A Munro, Derek Jones, Martin Buchan

Treatment of OA• NSAID’S

• Narcotics

• Synvisc injections

• Debriedment

• Uni-compartmentresurfacing

• Total knee replacement

• Shoe wedges

• Hinged knee sleeves

• Rigid frame KO’s

• KAFO’s

Orthoses

• Have been successfully used

• Pressures generated to provide offloading may not beeasily tolerated

• Designs may not be easily adjusted for optimal comfort

• May not be adequate with severe deformity

3 & 4 points ofpressure

Various pad & strapconfigurations

Long lever arms tocreate effective bending

moment

Single UprightDesigns

DoubleUprightDesigns

3 point pressuresystem

Single segmentadjustments

Within a “fixedframe”

V-VAS Concept• Total contact cuff

• Unique self-aligning adjustable joint

• Adjustable when on the body

• Femur and tibia - independent adjustment

• Unique application of corrective forces

• Made with custom cast or scan

Varum - Valgum Adjustable Stress V-VAS™

Adjustability

Captured Offloading

Dynamic Closed Frame

Adjust Optimal T/F Angle

Successful Applications

• Mild to Severe Genu Varum orValgum

• Non-Operative Tibial PlateauFixations

• Failed Tibial Plateau Reconstructions

• Osteochondral Defects

• Post Total-Knee Arthroplasty

• Tibial and/or Femoral Spacers

Cases

Mr AC - 84 years

Profile

• Bilateral knee OA

• Not fit for total knee

• Past History

• Ischaemic Heart Disease

• Lung cancer and lungresection

• Chronic Renal failure

• Anaemia

• Atypical mycobacteriumpulmonary infection

Clinical Management

•Hyaluronic acid and multiple steroidintra-articular injection providedminimal benefit

•Morphine patches for thoracic pain

•TB chemotherapy

Weight Bearing - No Brace

Weight Bearing - No Brace Braced

Mr AC

• Benefits

• Pain judged 60-70% improvement

• Improved walking distance limitedby respiratory problems ratherthan knee pain

• Issues

• Felt brace heavy and cumbersome

• Tricky to apply until correctapplication taught

• Significant weight fluctuationsinfluenced fitting

Interpretation

• Unbraced XRay - varus axis of 11 degrees

• Braced XRay - varus axis of 11 degrees

• Question

• Does brace work by preventing hingeadduction and compression of the medialjoint?

Mr MD - 44 years

Profile• 1985 left knee arthroscopy and

open medial menisectomy

• 1995 repeat arthroscopyshows complete loss of medialchondral surface

• 2005 right knee arthroscopyshows bone on bone contact

• Both knees have moderatePFJ and lateral compartmentchondral loss.

Without Brace - Stork View

Mr MD

Exam

• Bilateral clinical varus>20 degrees

• Both knees lack 5degrees fullextension

• Moderate effusionright knee only

• Severe pain andswelling right knee

Observations–Too young for jointreplacement–Too severe for chondralresurfacing–Too advanced for high tibialosteotomy–May be suitable for Benjamin’sdouble osteotomy

Mr MD

Following Bracing

• Brace used 2 - 4 hours per day

• Excellent reduction in pain andswelling of right knee

• Weight-bearing Xray

• No brace 11 deg Varus

• With brace 4 deg Varus

Mr ST - 66 years

Profile

• Right knee & left hiposteoarthritis

• Ex marathon runner

• Lateral menisectomy1963

• Knee arthroscopy in1989 showed patella-femoral and lateralcompartment wear

Past History–Coronary bypass grafts (re-stenosed)–Gout–Previous knee brace rejected in2005

Pain medication–Gabapentin–Paracetamol–Tramadol

Mr ST

Observations

• Pain disrupts daily activities

• Painful and unstable knee

• Steriod injection in left hip very helpful(December 2007)

• Steroid injection in right knee not helpful(September 2007)

Mr ST

Examination–20 degrees valgus–Correctable to neutral–Full extension to 120 degreesflexion–Xrays show bone on bonecontact in lateral compartmentsand PFJ–Mild OA medial compartments–Bone on bone hip OA

RequiredMeasurements

Via Cast or Scan

Benefits

• Manageable pain relief

• Increased tolerance to corrective forces

• No contact to knee area itself

• No need for counterforce strap

• Custom fit - Off the Shelf price