Background: The functional outcomes following ankle arthrodesis are
not known. The purpose of the present study was to compare the
intermediate-term clinical results for a group of patients in whom an ankle
arthrodesis had been performed with use of modern surgical techniques with the
findings for a group of healthy gender and age-matched controls on the basis
of validated outcome measures and gait analysis.
Methods: Twenty-six patients who had undergone ankle arthrodesis for
the treatment of isolated unilateral ankle arthritis were identified and
retrospectively assessed clinically and radiographically. The mean age at the
time of surgery was fifty-four years, and the mean interval between surgery
and assessment was forty-four months. A gender and age-matched control group
of twenty-seven individuals was recruited for comparison. All subjects were
evaluated with gait analysis, the American Orthopaedic Foot and Ankle Society
(AOFAS) Ankle-Hindfoot scale, the Musculoskeletal Outcomes Data Evaluation and
Management Systems (MODEMS) questionnaire, and the Ankle Osteoarthritis Scale
(AOS).
Results: On preliminary review, twenty of the twenty-six patients
were completely satisfied or satisfied with their surgical outcome. All
patients but one stated that they would undergo the surgery again. Five
patients stated that they did not notice a gait abnormality. Twelve patients
wore orthotics, and all believed that the use of the orthotics improved their
gait. When the functional outcome scores in the arthrodesis group were
compared with those in the control group, specific scores assessing hindfoot
pain and satisfaction were similar. However, scores focusing on ankle-hindfoot
function and disability revealed significant differences. Gait analysis also
identified significant differences between the two groups with regard to
cadence and stride length. In addition, there was significantly decreased
sagittal, coronal, and transverse range of motion of the hindfoot and midfoot
during the stance and swing phases of gait in the arthrodesis group.
Radiographic review demonstrated that four of the twenty-six patients had
development of moderate to severe arthritis of the subtalar joint.
Conclusions: In the intermediate term following an arthrodesis for
the treatment of end-stage ankle arthritis, pain is reliably relieved and
there is good patient satisfaction. However, there are substantial differences
between patients and the normal population with regard to hindfoot function
and gait. On the basis of these results, patients should be counseled that an
ankle fusion will help to relieve pain and to improve overall function;
however, it is a salvage procedure that will cause persistent alterations in
gait with a potential for deterioration due to the development of ipsilateral
hindfoot arthritis.
Level of Evidence: Therapeutic Level III. See
Instructions to Authors for a complete description of levels of evidence.