Orthotics CPM Exam Study Guide with
Complete Solutions
KAFO: Knee joint too distal - ANSWER-1. pressure at anterior distal and posterior
proximal thigh
2. thigh band shifts proximal
3. cant rotate as much as anatomical knee
KAFO: knee joint too proximal - ANSWER-1. pressure at posterior distal and anterior
proximal of thigh
2. thigh band shifts distal
3. bends too much
KAFO: knee joint too posterior - ANSWER-1. pressure at anterior proximal and posterior
distal thigh
2. orthosis shifts proximally
KAFO: knee joint too anterior - ANSWER-1. pressure at anterior distal and proximal
posterior thigh
2. orthosis shifts distally
AFO casting - ANSWER-1. Don gloves and gather materials
2. Take measurements either on form or calf circumference, ankle circumference, fib
head height, foot length
3. apply 2 layers of stockinette
4. mark landmarks: fib head/neck, tibial crest, malleoli, calcaneal tuberosity if prominent,
base of 5th met head, navicular, cuboid, met heads 1 and 5, to sulcus, any other
prominent/painful areas
5. apply cut tube anteriorly and insert into cut slits of stockinette
6. wrap with fiberglass, ensure fib head is captured
7. Use foot board to align foot as neutrally as possible
8. As fiberglass sets draw vertical cut line and horizontal match lines
9. Use cast saw to cut the cast off. Warn patient of vibration and loud noise. Use 2
hands and thumb as a guide
10. cut top layer of stockinette and remove cast
11. clean patients leg and remove 2nd layer stockinette. don shocks and shoes
12. Clean area and answer questions about patient considerations
KAFO: proper knee joint location - ANSWER-1. bisection of adductor tubercle and
medial tibial plateau
2. 60:40 anterior: posterior
KAFO Trimlines: - ANSWER-1. medial proximal 30 mm distal to perinneum
2. proximal lateral distal to greater trochanter
,3. proximal posterior thigh set at 15 deg slant connecting lateral to medial
4. popliteal region allows 105 deg knee flexion
KAFO knee joint clearances - ANSWER-6mm medial 3 mm lateral
KAFO ankle clearances - ANSWER-6 mm medial and 5 mm lateral
KAFO analysis - ANSWER-1. Correct side and foot plate
2. proper strapping materials
3. plastic thickness
4. rivets-- speedy rivets not durable for attaching metal uprights
5. plastazote /p-cell packs down quickly
6. check measurements
7. Check proper ankle and knee joints
8. If KAFO doesn't meet patient's needs do not deliver
KAFO : varus moment control - ANSWER-AFO section: 3 pt pressure 1) prox medial
(medial chafe at tibial strap) 2) proximal lateral malleoli (lateral flange) 3) 1st met head
(encompass)
KAFO hyperextension control after delivery - ANSWER-1) add padding to calf section
2) increase dorsiassist power (stiffer joints, adjust double action)
3) increase plantarflexion resistance (pf stop, adjust double action)
4) add heel wedge to AFO
KAFO joints that prevent hyperextension (without limiting ADLs) - ANSWER-1. posterior
offset
KAFO correct genuvarum/genuvalgum after delivery - ANSWER-1. add pull strap
proximal and distal to the knee joint so line of pull corrects deformity
2. add padding proximal and distal to KC (if valgus add padding medially, and if varus
add padding laterally) to increase corrective force
KAFO: pain at at posterior distal thigh indicates what? - ANSWER-knee joint is too
proximal
KAFO: pain at anterior distal thigh and posterior proximal thigh indicates what? -
ANSWER-knee joint is too distal
KAFO: what may be the issue if knee joints will not fully lock? - ANSWER-1. drop locks
may be upside down
2. mechanical KC not aligned with anatomical KC
3. The joints are not squared properly
4. excursion length are uneven
, Scenario: pt with metal and leather KAFO with drop locks and double action ankle joints
feels unsteady and trips easily going down ramps. what adjustments? - ANSWER-1.
allow more plantarflexion at the ankle
2. provide dorsiassist with a spring in the posterior channel (will resist pf and smooth the
foot flat transition)
3. add cushioned heel to shoe
AFO 3 point force system for dorsiflexion weakness (resist PF in swing): - ANSWER-1.
anteriorly directed force at posterior calf
2. posterior and distal force at dorsum of ankle (shoe, instep strap)
3. superiorly directed force at met heads (foot plate)
AFO 3 point force system for plantarflexion weakness (resist DF in stance): - ANSWER-
1. posterior directed force at tibia
2. anterior and proximal force at heel
3. distal directed force at met heads
AFO Full length footplate considerations - ANSWER-1. claw toes, hammer toes, toe
grasping
2. mid foot fracture
3. tone/spasticity
AFO hyperextension adjustments - ANSWER-1. heel wedge
2. taller proximal trimline
3. sent 3-4 deg dorsiflexion
4. footplate too rigid-- shorten to sulcus or metheads
AFO 3 point force system for valgus correction/ reduce pronation - ANSWER-1.
medially directed force at lateral proximal calf band (lateral chafe for tibial strap)
2. lateral directed force at medial supramalleolus (medial flange)
3. medially directed force at 5th methead (encapsulate)
AFO 3 point force for varus correction/ reduce supination - ANSWER-1. lateral directed
force at medial proximal calf band (medial chafe for tibial strap)
2. medial directed force at lateral supramalleolus (lateral flange)
3. laterally directed force at 1st methead (encompass)
AFO patient: valgus presentation - ANSWER-1. forefoot abduction
2. calcaneal valgus
3. 1st methead pain and callus
AFO patient: varus presentation - ANSWER-1. forefoot adduction
2. calcaneal varum
3. 5th methead pain and callus
3 foot plate lengths - ANSWER-1. full length-- distal to toes
Complete Solutions
KAFO: Knee joint too distal - ANSWER-1. pressure at anterior distal and posterior
proximal thigh
2. thigh band shifts proximal
3. cant rotate as much as anatomical knee
KAFO: knee joint too proximal - ANSWER-1. pressure at posterior distal and anterior
proximal of thigh
2. thigh band shifts distal
3. bends too much
KAFO: knee joint too posterior - ANSWER-1. pressure at anterior proximal and posterior
distal thigh
2. orthosis shifts proximally
KAFO: knee joint too anterior - ANSWER-1. pressure at anterior distal and proximal
posterior thigh
2. orthosis shifts distally
AFO casting - ANSWER-1. Don gloves and gather materials
2. Take measurements either on form or calf circumference, ankle circumference, fib
head height, foot length
3. apply 2 layers of stockinette
4. mark landmarks: fib head/neck, tibial crest, malleoli, calcaneal tuberosity if prominent,
base of 5th met head, navicular, cuboid, met heads 1 and 5, to sulcus, any other
prominent/painful areas
5. apply cut tube anteriorly and insert into cut slits of stockinette
6. wrap with fiberglass, ensure fib head is captured
7. Use foot board to align foot as neutrally as possible
8. As fiberglass sets draw vertical cut line and horizontal match lines
9. Use cast saw to cut the cast off. Warn patient of vibration and loud noise. Use 2
hands and thumb as a guide
10. cut top layer of stockinette and remove cast
11. clean patients leg and remove 2nd layer stockinette. don shocks and shoes
12. Clean area and answer questions about patient considerations
KAFO: proper knee joint location - ANSWER-1. bisection of adductor tubercle and
medial tibial plateau
2. 60:40 anterior: posterior
KAFO Trimlines: - ANSWER-1. medial proximal 30 mm distal to perinneum
2. proximal lateral distal to greater trochanter
,3. proximal posterior thigh set at 15 deg slant connecting lateral to medial
4. popliteal region allows 105 deg knee flexion
KAFO knee joint clearances - ANSWER-6mm medial 3 mm lateral
KAFO ankle clearances - ANSWER-6 mm medial and 5 mm lateral
KAFO analysis - ANSWER-1. Correct side and foot plate
2. proper strapping materials
3. plastic thickness
4. rivets-- speedy rivets not durable for attaching metal uprights
5. plastazote /p-cell packs down quickly
6. check measurements
7. Check proper ankle and knee joints
8. If KAFO doesn't meet patient's needs do not deliver
KAFO : varus moment control - ANSWER-AFO section: 3 pt pressure 1) prox medial
(medial chafe at tibial strap) 2) proximal lateral malleoli (lateral flange) 3) 1st met head
(encompass)
KAFO hyperextension control after delivery - ANSWER-1) add padding to calf section
2) increase dorsiassist power (stiffer joints, adjust double action)
3) increase plantarflexion resistance (pf stop, adjust double action)
4) add heel wedge to AFO
KAFO joints that prevent hyperextension (without limiting ADLs) - ANSWER-1. posterior
offset
KAFO correct genuvarum/genuvalgum after delivery - ANSWER-1. add pull strap
proximal and distal to the knee joint so line of pull corrects deformity
2. add padding proximal and distal to KC (if valgus add padding medially, and if varus
add padding laterally) to increase corrective force
KAFO: pain at at posterior distal thigh indicates what? - ANSWER-knee joint is too
proximal
KAFO: pain at anterior distal thigh and posterior proximal thigh indicates what? -
ANSWER-knee joint is too distal
KAFO: what may be the issue if knee joints will not fully lock? - ANSWER-1. drop locks
may be upside down
2. mechanical KC not aligned with anatomical KC
3. The joints are not squared properly
4. excursion length are uneven
, Scenario: pt with metal and leather KAFO with drop locks and double action ankle joints
feels unsteady and trips easily going down ramps. what adjustments? - ANSWER-1.
allow more plantarflexion at the ankle
2. provide dorsiassist with a spring in the posterior channel (will resist pf and smooth the
foot flat transition)
3. add cushioned heel to shoe
AFO 3 point force system for dorsiflexion weakness (resist PF in swing): - ANSWER-1.
anteriorly directed force at posterior calf
2. posterior and distal force at dorsum of ankle (shoe, instep strap)
3. superiorly directed force at met heads (foot plate)
AFO 3 point force system for plantarflexion weakness (resist DF in stance): - ANSWER-
1. posterior directed force at tibia
2. anterior and proximal force at heel
3. distal directed force at met heads
AFO Full length footplate considerations - ANSWER-1. claw toes, hammer toes, toe
grasping
2. mid foot fracture
3. tone/spasticity
AFO hyperextension adjustments - ANSWER-1. heel wedge
2. taller proximal trimline
3. sent 3-4 deg dorsiflexion
4. footplate too rigid-- shorten to sulcus or metheads
AFO 3 point force system for valgus correction/ reduce pronation - ANSWER-1.
medially directed force at lateral proximal calf band (lateral chafe for tibial strap)
2. lateral directed force at medial supramalleolus (medial flange)
3. medially directed force at 5th methead (encapsulate)
AFO 3 point force for varus correction/ reduce supination - ANSWER-1. lateral directed
force at medial proximal calf band (medial chafe for tibial strap)
2. medial directed force at lateral supramalleolus (lateral flange)
3. laterally directed force at 1st methead (encompass)
AFO patient: valgus presentation - ANSWER-1. forefoot abduction
2. calcaneal valgus
3. 1st methead pain and callus
AFO patient: varus presentation - ANSWER-1. forefoot adduction
2. calcaneal varum
3. 5th methead pain and callus
3 foot plate lengths - ANSWER-1. full length-- distal to toes
