Prospective Randomized Evaluation of a Two and Three Piece Total Ankle Replacement

To assess changes in pain across time following total ankle replacement. The visual analog scale (VAS) is a validated, subjective measure for acute and chronic pain. Scores are recorded by making a mark on a 100mm line that represents a continuum between "no pain" and "worst pain." A score of 0 represents less pain intensity while a score of 100 represents high pain intensity

The SF-36 comprises 36 questions which cover eight domains of health: Limitations in physical activities because of health problems, Limitations in social activities because of physical or emotional problems, Limitations in usual role activities because of physical health problems, Bodily pain, General mental health (psychological distress and well-being), Limitations in usual role activities because of emotional problems, Vitality (energy and fatigue), and General health perceptions. Scores for the different domains are converted and pooled using a scoring key, for a total score indicating a range of low to high Quality of Life (QOL). Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The lower the score the more disability. The higher the score the less disability i.e., a score of zero is equivalent to maximum disability

The SMFA consists of two sections: 34 questions covering the assessment of the patient's function and 12 questions covering how bothered patients are by their symptoms. Items are scored in six categories: daily activities, emotional status, arm and hand function, mobility category, and bother index. On a scale of 1 to 5, patients rate their ability on each item and higher total scores represent greater degree of dysfunction or bother. SMFA higher total score represent greater degree of dysfunction or bother. The lowest score is 0 representing the best possible function and the highest score is 100 representing an overall higher degree of dysfunction or bother.

The AOFAS Ankle-Hindfoot Rating System is a standardized evaluation of the clinical status of the ankle-hindfoot. Patients report their pain and physicians assess alignment; the patient and physician work together to complete the functional portion. Scores range from 0 to 100, with healthy ankles receiving 100 points.

The FADI has 26 items, each of which is scored from 0 (unable to do) to 4 (no difficulty at all). The four pain items of the FADI are scored 0 (none) to 4 (unbearable). The total score ranges 0 to 104 with higher scores indicating a better outcome.

In order to understand the effect of the ankle replacement on lower extremity kinematics and kinetics, each subject will be asked to complete a series of functional tasks and level walking trials at each of the study timepoints.