10-year Outcomes of High Tibial Osteotomy for Medial Compartment Osteoarthritis of the Knee Justin Roe Nick Howells, Lucy Salmon, Alison Waller, Leo Pinczewski North Sydney Orthopaedic and Sports Medicine Centre Australia

Disclosures I declare that in the past three years I have: held shares in:Optimized Ortho received royalties from:n/a done consulting work for:Stryker given paid presentations for:Smith and Nephew received institutional support from:Stryker Optimized Ortho Signed: Justin Roe Associate Professor Justin Roe

Aim Prospectively assess the long term clinical outcome of HTO Identify preoperative factors associated with HTO survivorship Associate Professor Justin Roe

Patient Selection Symptomatic medial compartment osteoarthritis with Clinical and/or radiologic bone on bone articulation in the medial compartment Kellgren Lawrence grades 3 and 4 Inclusion Criteria Modified Coventry lateral closing wedge osteotomy Consent to prospective research over 10 yrs Not receiving compensation

Method Enrollment Follow-Up + Analysis n=100 Excluded (n=64) Did not consent to prospective research over 10 years Workers Comp n = HTO Lost to follow-up n = 3 Deceased n = 2 Analysed n = 95 Further Surgery n = 21 Reviewed n = 74 Associate Professor Justin Roe

Assessment Preoperatively and at 5 and 10 years WOMAC KOOS Clinical Knee Society Score Long leg weight bearing alignment radiographs Associate Professor Justin Roe

Study Group n = 100 Mean age 50 years (26-66) 69 males (73%), 26 Females (27%) Mean BMI 28 (21-39) Mean Preop MechAxis varus

Operative Technique: Modified Coventry Closing Wedge HTO, Staple fixation, HKB 6 weeks Associate Professor Justin Roe

Overall Results (n = 97) At 10 years 21 proceeded to further surgery UKA n = 5 TKA n = 15 Revision HTO n = 1 Mean time to further surgery 60 months ( months) Associate Professor Justin Roe

Results Further surgery No surgery P No of patients2174 Preop WOMAC Preop KSS Mean Age Mean BMI No significant difference in preop alignment (p=0.69), preop diagnosis (p=0.42), MCL status (p=0.69), wedge size (p=0.10), gender (p=0.07) Associate Professor Justin Roe

HTO Overall Survivorship 87%79% Associate Professor Justin Roe

Survivorship Stepwise Multiple Regression Variable Hazard Ratio 95% CI p Preop WOMAC < Age > 55 years BMI > Relative contribution of each variable on increasing the Odds of Failure over 10 years Significant Results Associate Professor Justin Roe

BMI effect on Survivorship 82% 79% 71% 90%84% BMI < 30 BMI > 30 Significant Results Associate Professor Justin Roe

Age effect on Survivorship 69% 79% 63% 97%87% AGE < 55 yr AGE > 55 yr Significant Results Associate Professor Justin Roe

Australian Joint Registry 2012 Age < 555 yr10 yr HTO97%87% UKA87%77% TKA92%88% Associate Professor Justin Roe

Pre op WOMAC score effect on Survivorship 63% 79% 42% 93%88% WOMAC > 45 WOMAC <45 Significant Results Associate Professor Justin Roe

IDEAL BMI >30, >55yrs, WOMAC <45 Survivorship ‘IDEAL’ candidate (n=34) Age 45 80% 69% 100% 97% p = 0.01 Significant Results Associate Professor Justin Roe

10 year Clinical Outcomes Survivor Results (n=74) Associate Professor Justin Roe

Significant Results WOMAC and Age WOMAC Age 55 years P Preop year 86 93* year 82 89*0.04 Older patients had significantly better WOMAC scores at 5 and 10 years Survivor Results (n=74) Associate Professor Justin Roe

Discussion Previously unreported in the osteotomy literature Pre-op WOMAC score as a predictor of long term outcome for osteotomy Older patients age > 55 years have significantly higher 10 year WOMAC score outcomes than their younger counterparts, although lower survivorship 10 year prospective analysis HTO for Kellgren Lawrence grade 3 and 4 medial OA Associate Professor Justin Roe

Conclusion Closing Wedge High Tibial Osteotomy is confirmed in the literature as a safe and reliable option for medial compartment osteoarthritis of the knee HTO is the procedure of choice in patients Age < 55 years BMI < 30 preop WOMAC > 45 Associate Professor Justin Roe

Thank you for your attention. Associate Professor Justin Roe

APKASS Japan 2014 Associate Professor Leo Pinczewski

APKASS Japan 2014 Associate Professor Leo Pinczewski