Foot & Ankle International - September 2020 - 1123

Choi et al

1123
postoperative TT was 7.3 degrees of preoperative TT.
Furthermore, 4 cases with postoperative complications (1
deep infection followed by early implant removal, 1 fibular
osteotomy site nonunion, and 2 tibial implant breakages) were
excluded, as we concluded that these cases were unnecessary
to judge the isolated effect of the osteotomy. Finally, 31
patients were included in the study. Of the 31 total patients,
the mean age was 61.5 ± 7.3 years, and 17 were male. The
operation was performed on the right side in 18 patients.

Operative Technique and Aftercare

Figure 1. Asymmetric pressure concentration on the medial talar
dome worsened after low tibial osteotomy for ankle arthritis with
10 degrees of varus talar tilt (A, preoperative; B, postoperative).

To our knowledge, there have been no studies focusing
on the factors that contribute to successful correction of
largely varus TT with LTO. We hypothesized that LTO
could be an effective option for more significant varus tilt in
some situations. Therefore, we addressed the current debate
with the following research questions: efficacy of LTO for
more significant varus ankle arthritis, the effect of additional inframalleolar correction followed by LTO, and the
preoperative or operation-related factors influencing postoperative TT decrease.

Methods
This study was carried out in accordance with the Declaration
of Helsinki. Written informed consent was obtained from all
patients enrolled, and our institution's ethical review committee approved the study. The patient selection algorithm is
shown in the online supplemental material. In this study, we
retrospectively reviewed the radiographic and clinical findings of patients who underwent LTO between January 2008
and January 2018 for varus ankle arthritis with no paralytic
pes cavovarus deformity. Initially, 95 cases (91 patients) were
evaluated. Of these, patients were excluded if they had less
than 2 years of follow-up (10 cases) and/or systemic inflammatory disease such as rheumatoid arthritis or gout (5 cases).
Furthermore, 12 additional cases were excluded due to angular deformities of the proximal tibia and severe bony and/or
soft tissue injuries around the ankle. Among the remaining
cases, we selected only the patients with ≥8 degrees of preoperative varus TT (33 cases excluded), based on the opinion
by Lee et al20 that the optimal threshold for predicting high

Initially, open or arthroscopic examination of the medial
ankle joint with synovectomy was performed. In the open
group (29 cases), multiple drilling was done on the cartilagedenuded medial talar dome, while the microfracture technique was done through the arthroscopic approach (2 cases).
Then, a 4- to 5-cm longitudinal incision was made on the
medial supramalleolar area at the osteotomy site, starting at 5
cm proximal to the joint line. An oblique osteotomy was
made from medial to lateral going to the safe zone of the
syndesmosis.23 The osteotomy site was opened, and the gap
was filled with tricortical autograft from the anterosuperior
iliac crest (26 cases) or metal block combined with mixed
allogenous and autogenous bone graft (5 cases). The goal of
the surgery was to achieve a slight valgus overcorrection (2-5
degrees).10 The graft size to maintain the osteotomy opening
was measured intraoperatively after planned correction was
successfully achieved under fluoroscopy.
To secure the osteotomy site firmly, the plate and screws
were fixed. Then, additional fibular osteotomy was performed 0.5 to 1 cm proximal to the tibial osteotomy site in
26 cases. In the early cases, a decision for a fibular osteotomy was determined intraoperatively after LTO. After some
initial cases, we routinely added the fibular osteotomy, as
we believed that fibular osteotomy would be beneficial to
correct the varus TT.11,26 Then, complete deltoid ligament
release from the medial malleolus was performed in all
cases. An additional modified Broström operation was performed in 10 cases when the persistent lateral ankle instability was observed after LTO.
Operations were performed by 2 surgeons. Postoperatively, weightbearing was prohibited in a below-knee cast
for 6 weeks. Then, partial weightbearing without a cast was
permitted, and full weightbearing was allowed from 3
months postoperatively when adequate radiographic bony
union was achieved. Hardware removal was performed in
25 cases, with additional second-look examination of the
medial talar dome cartilage in 2 out of 25 cases.

Assessments
We divided the patients into 2 subgroups according to the
combined inframalleolar correctional operation. LTO alone

Foot & Ankle International - September 2020

Table of Contents for the Digital Edition of Foot & Ankle International - September 2020