Foot & Ankle International - 2017 FAI Supplement - 14S

tested under normal physiological loading conditions. Axial
loads of 50 Newton (N) and 700N were provided in an intact
state and after sequential sectioning of the following ligaments: anterior-inferior tibiofibular (AITFL), posterior-inferior tibiofibular (PITFL), interosseous (IOL), and whole
deltoid (DL). In each condition the specimens were tested in
neutral position, 10 degrees of dorsiflexion, 30 degrees of
plantar flexion, 10 degrees of inversion, 5 degrees of eversion, and externally rotated up to 10Nm torque. Finally, after
sectioning of the deltoid ligament, we triangulated Boden's
classic findings with modern instruments. We hypothesized
that only after sectioning of the deltoid ligament; the lateralization of the talus will push the fibula away from the tibia.
Results: During dorsiflexion and external rotation the ankle
syndesmosis widened, and the fibula externally rotated after
sequential sectioning of the syndesmotic ligaments. After the
AITFL was sectioned the fibula starts rotating externally.
However, the external rotation of the fibula significantly
reduced when the external rotation torque was combined
with axial loading up to 700N as compared to the external
rotation torque alone. The most relative moments between
the tibia and fibula were observed after the deltoid ligament
was sectioned.
Conclusion: Significant increases in movements of the fibula relative to the tibia occur when an external rotation torque
is provided. However, axial pressure seemed to limit external
rotation because of the bony congruence of the tibiotalar surface. The AITFL is necessary to prevent the fibula to rotate
externally when the foot is rotating externally. The deltoid
ligament is the main stabilizer of the ankle mortise.
Foot & Ankle International, 38(S1)
DOI: 10.1177/1071100717S00010
©The Author(s) 2017

Perioperative Complications of
Outpatient Total Ankle Arthroplasty
Todd Borenstein, MD, David B. Thordarson, MD,
Timothy P. Charlton, MD, Stephanie Chen, NP
Category: Ankle Arthritis
Keywords: outpatient total ankle arthroplasty
Introduction/Purpose: Total ankle arthroplasty (TAA) is
commonly pursued for patients with painful arthritis. As the
number of TAA increases, so too will the associated economic burden. In the current healthcare environment, savings

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are in the national spotlight. Studies of total joint arthroplasty
(THA and TKA) have demonstrated that outpatient surgery
decreases surgical costs.1,2 Additionally, outpatient THA
and TKA have not been associated with increased complication or readmission rates.3-6 Outpatient TAA are becoming
more common which may lead to decreased costs of care.
Despite the potential savings, TAA remains an "inpatientonly procedure" for Medicare patients. Currently, there are
no clinical studies examining the safety of outpatient TAA. In
this study, we retrospectively reviewed 65 consecutive outpatient TAA to identify complication rates and patient risk
factors.
Methods: The medical records of 65 consecutive outpatient
TAA from October 2012 to May 2016 with a minimum of
6-month follow-up were reviewed. All patients received popliteal and saphenous blocks with bupivacaine and epinephrine
prior to surgery and were managed with oral NSAID and narcotic pain medication post-operatively. All patients received a
STAR total ankle prosthesis. Demographics, comorbidities,
ASA and perioperative complications including wound breakdown, infection, revision and non-revision surgeries were
compared to historic controls. Mean follow up was 16.6 +/- 9.1
months (range, 6-42 months).
Results: The overall complication rate in this series was
21.8%. One ankle (1.5%) had a wound breakdown requiring debridement and flap coverage. This patient had a history of Polycythemia Vera with re-thrombosis of their
popliteal artery one month after TAA surgery. Two ankles
(3%) had deep infections. Nine ankles (13.8%) required
non-revision surgery. Three ankles (4.6%) required posterior capsular release, one ankle (1.5%) required medial malleolar screws for symptomatic stress reaction, and three
ankles (4.6%) required arthroscopic or open gutter release.
Two ankles (3%) required revision surgery. One for talar
component subsidence in a patient with Charcot-MarieTooth managed with an arthrodesis at eleven months. The
other revision was performed for aseptic tibial component
loosening and managed with conversion to an INBONE
prosthesis at seven months.
Conclusion: This study demonstrates the safety of outpatient
TAA. The combination of regional anesthesia and oral narcotics provided a satisfactory outpatient experience and zero
patients required readmission for pain control. The one
wound complication (1.5%) was attributed to arterial occlusion and not outpatient management. This compares to the
6.6-28% wound breakdown rate found in the literature.7-10
Our revision surgery rate (3%) was comparable to the 3.116.5% rate found in the literature, and was also not attributed
to outpatient management.7-10 We feel this demonstrates
that outpatient TAA can be performed safely.

Foot & Ankle International 38(1S)

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