3. DISCUSSION
In these cases, HTO was an effective procedure to treat medial
osteoarthritis in co-directional varus deformities at the knee and ankle
of the same leg. Re-alignment of the proximal tibia leads to changes in
ankle pressure, which could be beneficial in guiding the treatment of
patients with medial osteoarthritis of the ankle.
HTO may influence the alignment and symptoms of the ankle joint. The
effects of the HTO on the biomechanics of the ankle joint remain
controversial. Several studies reported that the correction of severe
varus deformity of the knee joint with HTO or TKA could result in pain
and osteoarthritis progression of the ankle
joint.5,8,9 Jeong and SooHoo8reported the case of a patient with persistent ankle pain after
bilateral HTO for the treatment of osteoarthritis in both knee joints,
which was treated with a corrective supramalleolar osteotomy of the
ankle. Lee and Jeong5 reported that 21.8% of the
patients had newly developed or progressive ankle arthritis after TKA in
a series of 142 TKA cases. Graef et al.9 reported that
the excessive correction of knee malalignment after TKA was associated
with worse postoperative function in the ankle joint. In contrast,
Takeuchi et al.10 reported the successful treatment of
16 HTOs in ten patients with osteoarthritis of the ipsilateral knee and
ankle joints. Elson et al.11 presented the case of a
patient with medial ankle pain and lateral instability in whom an HTO
was performed, resulting in significant resolution of the ankle
symptoms. Recently, Kim et al.12 reported that the
correction of a knee varus deformity with HTO or TKA could improve the
symptoms of medial ankle arthritis but could worsen lateral ankle
arthritis. These reports corresponded to improvements in the symptoms of
medial osteoarthritis in the ankle joint following HTO in our cases.
In well-planned and selected cases, HTO may be effective in treating not
only the knee but also overload of the ankle in patients with
ipsilateral double-joint osteoarthritis.