Foot & Ankle International - July 2018 - 789

789

Saito et al.
Table 1. Concomitant Procedures Performed During Primary
TAA.
Procedure
Gastrocnemius recession
Achilles lengthening
Prophylactic fixation of medial malleolus
Removal of hardware
Calcaneal osteotomy
Modified Brostrom procedure
Fibular lengthening
Peroneus longus to brevis transfer
Cotton osteotomy
Talonavicular fusion
First and second tarsometatarsal fusion
Other proceduresa

No. (n=60)
17
12
7
5
4
4
2
1
1
1
1
5

Other procedures include posterior tibial tendon debridement,
resection of neuroma, calcaneo-navicular coalition resection and flexor
tendon tenotomies.

weightbearing was introduced and physical therapy was initiated. The walking boot was replaced by a regular shoe at
the 8-week follow-up visit and physical therapy was maintained until 4 months after surgery.

Clinical Assessment
Medical records were reviewed for complications, reoperations, and revision procedures. Complications were defined
according to the Glazebrook et al8 classification system.
However, complications observed during the study that
were not defined in the Glazebrook classification were also
included. Revision was defined as failure of any metallic
component of the prosthesis with subsequent removal and
implantation of a new metal component, or conversion to an
arthrodesis or amputation.2,27
Patient-reported outcomes as measured with the Foot and
Ankle Outcome Score (FAOS)21 for pain, symptoms, activities of daily living, and quality of life were analyzed preoperatively and 1 year postoperatively. The FAOS has been
previously validated for use in patients with ankle arthritis,
including a large cohort of patients undergoing TAA.

Radiographic Analysis
Radiographic analysis was performed using the digital
PACS (picture archiving and communication system)
(General Electric Healthcare, UK). All measurements and
analysis were based on conventional weightbearing ankle
radiographs, and performed by an independent fellowshiptrained foot and ankle surgeon who was blinded to the clinical outcomes of the patients and to the surgeon who had
performed the operative procedure. Radiographic analysis
were performed based on weightbearing images obtained
during our standard radiographic routine, which included

bilateral anteroposterior images of the ankle on the same
cassette, mortise and lateral radiographs of the affected
ankle, and a hindfoot alignment view. Measurements of
tibial implant position and tibiotalar alignment were performed on preoperative weightbearing radiographs, on the
first postoperative weightbearing radiograph 8 weeks after
surgery, and at the last follow-up visit. For patients who
underwent revision procedures, the last measurement was
performed on the last radiograph before the revision
procedure.
Implants were assessed for loosening, subsidence, and
the presence of radiolucencies and cysts based on the analysis and comparison of all postoperative weightbearing ankle
radiographs available. Criteria for loosening was pain with
weight-bearing that was associated with radiolucency at the
implant-bone interface without evidence of osseous
ongrowth.32 Subsidence was defined as a change of tibial
component alignment greater than 5 degrees4 or a change in
the vertical position of the talar component of 5 mm or
more.6 A periprosthetic cyst was defined as a hypodense
zone greater than 5 mm in diameter with no inner bone trabeculae.3 Subsidence, radiolucent lines, and cysts were
deemed nonprogressive when no change in position or size
was noted with comparison of the last 2 radiographs.
Pre- and postoperative tibiotalar coronal alignment were
measured on weightbearing anteroposterior radiographs,
and defined as the angle between the anatomic axis of the
tibia and a line perpendicular to the talar dome or talar component, respectively17,23 (Figure 3A, B). Tibiotalar coronal
deformity was defined as the absolute difference between
the tibiotalar coronal alignment and 90 degrees. Tibiotalar
coronal deformity of less than 5 degrees was defined as
neutral alignment, as reported in previous studies.11,23 Tibial
implant alignment was defined as the angle between the
tibial anatomic axis and the lower border of the tibial component1,13 (Figure 4A, B). Tibial component deviation was
defined as the absolute difference between the tibial implant
alignment and 90 degrees.

Statistical Analysis
Descriptive statistics was used to report demographic data,
complications, and reoperations. The Shapiro-Wilk normality test was used to assess the distribution of the data.
Comparison of pre- and postoperative data was performed
by either a paired t test or each pair Wilcoxon analysis. P
values of less than .05 were considered significant.

Results
Complications, Reoperations, and Survivorship
A total of 17 complications in 14 ankles (21.8%) were noted
(Table 2). The most frequent complication was gutter impingement, which occurred in 5 cases (7.8%). Other complications

Table of Contents for the Digital Edition of Foot & Ankle International - July 2018