Evaluation of Epidemiology and Radiological and Clinical Outcomes in Total Ankle Prosthesis

Changes in beta angle

时间窗: 2 months post-operatively, 6 months post-operatively, 12 months post-operatively, 24-36-48-60-72-84-96-108-120 months post-operatively

β-angle (normal value 85.0 ± 2.0 degrees). This angle is subtended anteriorly by the longitudinal axis of the tibia and the articular surface of the tibial component on the lateral view

Medial distal tibial angle

时间窗: Pre operatively

It is the angle between the anatomic axis of the tibia and the line connecting the distal point on the medial and lateral articular surface. (normal value 92.4 ± 3.1 degrees).

Anterior distal tibial angle

时间窗: Pre operatively

(ADTA: normal value 83.0 ± 3.6 degrees). The angle is subtended by the anatomic axis of the tibia and the line connecting the distal points on the anterior and posterior tibial articular surface on the anterior side (Figure 1). The tibia axis was defined as the line connecting the centres of two circles designed over the proximal and the distal tibia adjusting their radius to the anterior and posterior tibial cortices.

Changes in alpha angle

时间窗: 2 months post-operatively, 6 months post-operatively, 12 months post-operatively, 24-36-48-60-72-84-96-108-120 months post-operatively

the α-angle is formed by the angle between the anatomic axis of the tibia and the articular surface of the tibial component on the AP view (normal value 90.0 ± 2.0 degrees)

Changes in Short form 12 (SF 12)

时间窗: Pre operatively, 2 months post-operatively, 6 months post-operatively, 12 months post-operatively, 24-36-48-60-72-84-96-108-120 months post-operatively

The SF-12 is a multipurpose short form survey with 12 questions, all selected from the SF-36 Health Survey (Ware, Kosinski, and Keller, 1996). The questions were combined, scored, and weighted to create two scales that provide glimpses into mental and physical functioning and overall health-related-quality of life. Physical and Mental Health Composite Scores (PCS \& MCS) are computed using the scores of twelve questions and range from 0 to 100, where a zero score indicates the lowest level of health measured by the scales and 100 indicates the highest level of health.

Changes in American orthopaedic foot and ankle society (AOFAS) ankle-hindfoot score

时间窗: Pre operatively, 2 months post-operatively, 6 months post-operatively, 12 months post-operatively, 24-36-48-60-72-84-96-108-120 months post-operatively

The American orthopaedic foot and ankle society (AOFAS) ankle-hindfoot score combines subjective scores of pain and function provided by the patient with objective scores based on the surgeon's physical examination of the patient (to assess sagittal motion, hindfoot motion, ankle-hindfoot stability and alignment of the ankle-hindfoot). The scale includes nine items that can be divided into three subscales (pain, function and alignment). Pain consists of one item with a maximal score of 40 points, indicating no pain. Function consists of seven items with a maximal score of 50 points, indicating full function. Alignment consists of one item with a maximal score of 10 points, indicating good alignment. The maximal score is 100 points, indicating no symptoms or impairments.