Computer-Assisted High Tibial and Double Level Osteotomies for Genu Varum Deformity

Medial compartment knee osteoarthritis is not uncommon and high tibial osteotomy (HTO) was described for the first time more than 50 years ago (Jackson, JP & Waugh, W 1961; Judet, R &Dupuis, JF & Honnard, F 1964; Merle d’Aubigné, R & Ramadier, JO 1961). Nowadays, it remains a good option (Coventry, MB & Ilstrup, DM & Wallrichs, SL 1993; Hernigou, Ph & Medevielle, D & Debeyre, J 1987; Jenny JY & Tavan, A & Jenny, G, et al 1998; Lerat, JL 2000; Lootvoet, L & Massinon, A & Rossillon, R, et al 1993; Papachristou, G & Pleassa, S & Sourlas, J & Levidiotis, C & Chronopoulos, E & Papachristou, C 2006; Rinonapoli, E & Mancini, GB & Corvaglia, A, et al 1998; Saragaglia, D & Blaysat, M & Inman, D & Mercier, N 2010; Yasuda, K & Majima, T & Tsuchida, T, et al 1992) despite the large expansion of total knee replacement (TKR) or the revival of unicompartmental knee prosthesis boosted by the less-invasive surgery concept. Ideally, HTO is indicated for active patients who are less than 65 years of age with moderate arthritis (narrowing joint line up to 100% without any bone wear or joint instability). Nevertheless, special attention should be paid to joint line orientation which can be distorted by excessive over or under correction which will eventually lead to earlier failure (Saragaglia, D & Blaysat, M & Inman, D & Mercier, N 2010) due to obliquity of joint line (Fig.1). This oblique joint line corresponds to an excessive valgus of the tibial mechanical axis (Babis, GC & An, KN & Chao, E. YS, et al 2002). Moreover, varus knee deformity may be a result of both tibial and femoral deformities. Correction of combined (femoral and tibial) varus deformity at the tibia level by (3o to 6°) to achieve a good clinical result may worsen the obliquity of knee joint line.