The effect of standard heel and positive posterior heel flare of orthopedic shoeon vertical ground reaction forces during walking

Introduction: in normal walking, repetitive vertical ground reaction forces are tansformed on musculo-skeletal system. Magnitude of force during impact is major contributor to overuse injuries. Purpose of thisstudy was the evaluate to effect of standard and positive posterior heel flare at orthopedic shoe on vertical ground reaction forces during walking in healthy subjects. Materials and Method: 30 healthy adults (12 male, 18 female) participated in this study. Subjects walked along an8-mwalkway in two different conditions: orthopedic shoe with standard heel and orthopedic shoe with positive posterior heel flare. Vertical ground reaction force data collected in initial stance phases of walking using Kistler force plate. Results: results of this study showed significant reduction in impact force in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel (p˂0.0001). No differences between conditions were observed in impact force time and first peak of vertical force. time of First peak of vertical force showed significant increasing in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel(p˂0.05). loading rate showed significant reduction in orthopedic shoe with positive posterior heel flare compared with the orthopedic shoe with standard heel(p˂0.05). Conclusion: using positive posterior heel flare reduce the impact force and loading rate that could be due to its flexibility and impact absorption of this heel during walking. because of complication of these loads on lower limb specially in early phase of walking we could use of this type of flare for some of the patient with special orthopedic disease.