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was performed in 21 cases, whereas LTO with inframalleolar correction was performed in 10 patients. Dwyer's valgization closed-wedge calcaneal osteotomy (Dwyer's
osteotomy) with first metatarsal (MT) dorsal closing wedge
osteotomy was performed in 7 cases, followed by 1 case of
Dwyer's osteotomy with double arthrodesis (talonavicular
and calcaneocuboid joints) and 1 case of subtalar arthrodesis. In 1 case, Dwyer's osteotomy with first MT dorsal closing wedge osteotomy and tibialis posterior tendon
lengthening was also performed at 1 year after LTO.
All radiographic parameters were measured preoperatively and at the final follow-up. On standing ankle anteroposterior radiographs, the TAS,19 TT, talocrural angle (TCA),
gap between the medial talar dome and the plafond (MTDP), and tibiomedial malleolar angle (TMAA) were measured
(Figure 2). The position of the talus in the coronal plane was
evaluated with 2 parameters: migration of the talar center
and migration of the talar dome center. The talar center was
defined as a point located on the line connecting the medial
and lateral malleolar tips. It was assumed that a circle originating from the center of the talus was tangential to the midpoint of the talar dome.1 Migration of the talar center was
defined as the shortest distance from the talar center to the
tibial axis. Likewise, we measured the migration of the talar
dome center as the shortest distance from the talar dome
center to the tibial axis. For both talar center and talar dome
center migrations, a positive value represented lateral translation of the talus. Then, we measured the talar lateral surface (TLS) angle on the standing lateral ankle radiographs.
The hindfoot alignment angle (HAA), hindfoot moment
arm (HMA),25 and hindfoot alignment ratio (HAR)16 were
measured on hindfoot alignment radiographs, as described
by Saltzman and el-Khoury.25 HAA was defined as the
angle created by a line drawn from the most inferior point
of the calcaneus to the intersection of the tibial axis with the
joint line.6,7 A positive value represented varus deformity of
the hindfoot. HMA was defined as the distance from the
most inferior point of the calcaneus to the tibial axis. When
the most inferior point of the calcaneus was located medial
to the tibial axis, it was considered a positive value. HAR
was obtained by dividing the width of the calcaneus medial
to the tibial axis by the calcaneal width at its widest point.
All radiographic parameters were measured by 2 orthopedic surgeons. To determine the interobserver reliability
and intraobserver reproducibility, all 31 enrolled cases were
reviewed twice with a 2-month interval between readings.
The intraclass correlation coefficients (ICCs) were used,
and the statistical results are shown in Appendix 1 (available online).
The clinical outcomes were evaluated using the American
Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and the Foot and Ankle Ability Measure (FAAM)
activity of daily living (ADL) scores. We checked these 2
parameters in the outpatient clinic preoperatively and at
every postoperative follow-up. The AOFAS scale was used

Foot & Ankle International 41(9)
to assess pain (40 points), function (45 points), and alignment (15 points), with a score of 100 representing the best
possible outcomes. FAAM scores22 ranged from 0 to 84 for
the ADL subscale.

Statistical Analyses
The mean and standard deviation of all dependent parameters were calculated using SPSS version 21 (SPSS, Inc).
Data normality was tested using a Kolmogorov-Smirnov
test. For all patients, a paired t test was used to compare the
preoperative and postoperative radiographic and clinical
parameters. To compare the radiographic parameters and
amount of radiographic changes between the 2 subgroups
according to the concomitant inframalleolar correction, a
Mann-Whitney test was used. In addition, all cases were
divided into 2 subgroups depending on the postoperative
TT change (decreased vs maintained or increased). A binary
logistic regression analysis was performed to determine the
preoperative or operation-related factors influencing postoperative TT decrease. Statistical significance was determined as a P value less than .05 for all analyses.

Results
Overall Patients' Radiographic/Clinical
Parameters
The mean preoperative TT was 12.1 ± 5.9 degrees (range,
8-34.5 degrees), and the mean graft size was 9.5 ± 2.1 mm
(range, 5-13 mm). All preoperative and postoperative radiographic and clinical parameters of all patients are shown in
Table 1. At a mean follow-up of 48.9 ± 19.4 months (range,
24-84 months), the TAS and MTD-P gap were significantly
increased (P < .001 and 0.019, respectively), whereas the
TT, TCA, and TLS remained unchanged. TMMA was significantly decreased after the operation (P < .001). Both the
talar and talar dome centers were medial to the tibial axis
preoperatively and significantly laterally translated postoperatively (both P < .001). We also confirmed that preoperative varus hindfoot alignment was corrected to nearly
normal. Regarding clinical outcome, both the AOFAS
ankle-hindfoot (from 41.7 to 78.2) and FAAM-ADL scores
(from 35.8 to 69.2) increased significantly (both P < .001),
although the TT was unchanged (P = .052).

Effect of Concomitant Inframalleolar Correction
The comparisons of the preoperative and postoperative
parameters and correctional power (the difference between
the postoperative and preoperative values) of all radiographic parameters between the 2 subgroups (with and
without inframalleolar correction) are presented in Table
2. Concomitant inframalleolar correction was performed
for patients with more hindfoot varus deviation. Although

Foot & Ankle International - September 2020

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