James W. Brodsky, M.D.

Posted June 15th 2017

Kinematics and Function of Total Ankle Replacements Versus Normal Ankles.

James W. Brodsky M.D.

James W. Brodsky M.D.

Kane, J. M., S. Coleman and J. W. Brodsky (2017). “Kinematics and function of total ankle replacements versus normal ankles.” Foot Ankle Clin 22(2): 241-249.

Full text of this article.

End-stage ankle arthritis produces severe functional disability, quantifiable by gait abnormalities. In all categories of gait parameters, total ankle arthroplasty (TAA) satistically significantly improves function, compared to patients’ preoperative function. There are increases in step length, cadence and velocity; in sagittal plane motion of the ankle, as well has hip and knee motion, and in ankle power and moment. These functional gait improvements correspond to clinical improvements of pain relief and satisfaction. Although these improvements fail to reach the functional performance of healthy controls, the improvement over preoperative function is clinically meaningful and statistically significant.


Posted October 15th 2016

Abnormalities of gait caused by ankle arthritis are improved by ankle arthrodesis.

James W. Brodsky, M.D.

James W. Brodsky, M.D.

Brodsky, J. W., J. M. Kane, S. Coleman, J. Bariteau and S. Tenenbaum (2016). “Abnormalities of gait caused by ankle arthritis are improved by ankle arthrodesis.” Bone Joint J 98-b(10): 1369-1375.

Full text of this article.

AIMS: The surgical management of ankle arthritis with tibiotalar arthrodesis is known to alter gait, as compared with normal ankles. The purpose of this study was to assess post-operative gait function with gait before arthrodesis. PATIENTS AND METHODS: We prospectively studied 20 patients who underwent three-dimensional gait analysis before and after tibiotalar arthrodesis. Cadence, step length, walking velocity and total support time were assessed. Kinetic parameters, including the moment and power of the ankle in the sagittal plane and hip power were also recorded. RESULTS: Significant improvement was recorded across numerous parameters compared with pre-operative measurements. Temporal-spatial data demonstrated a significant increase in step length (p = 0.003) and velocity (p = < 0.001). Total support time decreased for the unaffected limb (p = 0.01). Kinematic results demonstrated that in the affected limb, total sagittal range of movement did not change significantly (p = 0.1259). However, the arc of movement had a near congruent shift with mean maximal dorsiflexion increasing from 5 degrees (-17 degrees to 16 degrees ) to 12 degrees (5 degrees to 18 degrees ) (p < 0.001) and mean maximal plantarflexion decreasing from 6.8 degrees (6 degrees to 21 degrees ) to 0.9 degrees (-9 degrees to 8 degrees ) (p = 0.003). Mean hip joint range of movement increased by 6 degrees (-7 degrees to 24 degrees ; p = 0.003). Kinetic results demonstrated no statistically significant change in ankle power (p = 0.1292). However, there was an increase in ankle moment (p = 0.04) and hip power (p = 0.01) in the surgically treated extremity. Sagittal plane range of movement was not reduced after tibiotalar fusion. CONCLUSION: Although following tibiotalar arthrodesis the gait demonstrated never matched the gait shown in unaffected ankles, compared with the pre-operative analysis there was improvement in numerous temporal-spatial, kinematic, and kinetic measures.