South West Orthopedic Designs

Innovations in Design and Fabrication

Casting for the South West AFO

Perhaps the single most important element in successfully fitting the patient is the cast impression. It is assumed that at this point the patient's lower limb can be placed into a biomechanically correct position. The patient should be seated in a firm chair with arm rests. The foot must easily reach the floor and be plantargrade. Once the casting position is established, the patient must not alter his or her position in the chair. Any such movements will certainly change the pre-determined knee flexion and dorsiflexion angles. A contoured foot board is required.

The pre-casted position of the lower limb should be as follows:

• Hip at 90-95° of flexion;
• Knee at 90° of flexion;
• Foot / ankle at 90° on a 1/2 inch contoured foot board (shoe heel height);
• Induce subtalar neutral at 90° on contoured foot board.

Identify and mark the following landmarks:

• Lateral malleolus and 2" proximal to it
• Achilles tendon
• Apex of posterior calcaneus
• Navicular
• Base of the fifth metatarsal head
• Medial malleolus
• First tarsal
• Proximal and distal aspects, medial side of first metatarsal head

Carefully establish and mark the distal trimline for the footplate. Place surgical tubing over the cast sock and have the patient maintain the hose on the center of the knee. Without tension, apply one role of elastic plaster bandage followed by one roll as it sets. Hold the foot/ankle in 90° subtalar neutral position. As the plaster sets, recheck the position of the ankle, knee and hip. The position of the casted limb should be identical to that of the pre-casted limb. Finally, index the cast, remove from patient and staple together. The finished orthosis should provide the wearer with uniform total-contact comfort, in a biomechanically correct attitude. Please wait for the cast to dry before shipping. Then fill out the South West Ankle Brace work order completely.