GENTZ Gesellschaft für Entwicklung und Vertrieb von ... · This poster was presented at the 15th...
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About the Necessity of a Dorsal Stop in KAFOs for Patients with Paralyses and Weak Plantar Flexors Daniel Sabbagh 1 , Jörg Fior 1 , Ralf Gentz 1 1 FIOR & GENTZ Gesellschaft für Entwicklung und Vertrieb von orthopädietechnischen Systemen mbH, Lüneburg, Germany Which indications may cause plantar flexor (PF) weakness? • Spinal Cord Injury • Spina Bifida or MMC • Post Polio Syndrome and other indications Too weak or prolonged PFs lead to additional instability while standing or walking. The goal of an orthotic fitting is to restore a physiological gait pattern in patients with PF weakness. A knee-ankle-foot orthosis (KAFO) can improve poor knee stability and muscular control. To ensure a most effective KAFO, it should be produced with a dorsal stop. The aim is to point out effects of too weak PFs on gait patterns and to underline the need of a dorsal stop in case of PF weakness. Too weak or prolonged PFs can be responsible for an inactive forefoot lever. Therefore, KAFOs should always be produced using ankle joints with adjustable dorsal stops (fig. 2). How to check the correct dorsal stop position on the work bench: 1) Press the KAFO with foot piece into the designated shoe. 2) Put the KAFO shell into dorsal stop position. The line of gravity should pass through the middle of the femoral shell and ventrally ahead of the ankle joint. The KAFO should stand unassisted. How to check on your patient: Stable balance efficacy can be visualised by slightly leaning the body‘s centre of gravity forwards and backwards (fig. 3 a). For the visualisation of a correct dorsal stop in a dynamic situation check if your patient achieves a heel rise in terminal stance (fig. 3 b). Fig. 2: Ankle joints with individually adjustable range of motion and dorsal stop in form of an ankle joint with an adjustable dynamic dorsiflexion stop (a) or in form of an ankle joint with an adjustable hard dorsiflexion stop (b) built in a stance control KAFO (c). Tab. 1: Effects of inactive and active forefoot lever on gait parameters to achieve stable balance. Fig. 3: Visualisation of the KAFO’s dorsal stop on the patient in a static (a) and a dynamic situation (b). The biomechanics and gait patterns of healthy patients and a patient with weak PFs have been considered, including an evaluation of worn KAFOs. PF weakness causes inactivation of the forefoot lever (fig. 1). The activation of the forefoot lever is needed to achieve stable balance (tab. 1). Fig. 1: Knee and ankle kinematics of a patient with PF weakness (dotted line) wearing a KAFO with a wrong dorsal stop (DS; dashed line) and with a correct dorsal stop (DS; solid line) compared to a physiological reference group (grey band). The vertical lines represent the heel off. normal PFs 0 -40 100 [% GC] -40 30/-30 80 Plant Ankle Dors Ext Flex Knee [°] [°] w KAFO, correct DS w KAFO, wrong DS w/o KAFO, weak PFs Literature [1] Beekmann C, Perry J, Boyd LA, Newsam CJ, Mulroy SJ. Topics in Spinal Cord Injury Rehabilitation. 2000; 5(4): 54–62 [2] Ploeger HE, Bus SA, Brehm MA, Nollet F. Gait and Posture. 2014; 40(3): 391–398 [3] Mulroy SJ, Eberly VJ, Gronley JK, Weiss W, Newsam SJ. Prosthetics and Orthotics International. 2010; 34(3): 277–292 Background and Aim Materials and Methods Results Discussion and Conclusion Results Conclusion: A correctly adjusted dorsal stop is absolutely necessary for all orthoses for patients with paralyses and weak PFs to provide safety while standing and to improve gait pattern. Inactive forefoot lever Security decreased increased Step length decreased longer Contralateral knee flexion increased physiological Terminal stance a c 5° 15° b Heel remains on the floor lifts from the ground Body‘s centre of gravity too low correct Active forefoot lever w/o KAFO, weak PFs w KAFO, wrong DS w KAFO, correct DS normal PFs a b 2° 4° 6° 8° 10° 15° 20° This poster was presented at the 15th ISPO world congress in Lyon, France, 22nd - 25th June 2015. PR8306-DE/GB-09/2015
Transcript of GENTZ Gesellschaft für Entwicklung und Vertrieb von ... · This poster was presented at the 15th...
About the Necessity of a Dorsal Stop in KAFOs for Patients with Paralyses andWeak Plantar Flexors
Daniel Sabbagh1, Jörg Fior1, Ralf Gentz1
1FIOR & GENTZ Gesellschaft für Entwicklung und Vertrieb von orthopädietechnischen Systemen mbH, Lüneburg, Germany
Which indications may cause plantar flexor (PF) weakness?
• Spinal Cord Injury• Spina Bifida or MMC• Post Polio Syndrome and other indications
Too weak or prolonged PFs lead to additional instability while standingor walking. The goal of an orthotic fitting is to restore a physiological gaitpattern in patients with PF weakness. A knee-ankle-foot orthosis (KAFO)can improve poor knee stability and muscular control. To ensure a mosteffective KAFO, it should be produced with a dorsal stop.
The aim is to point out effects of too weak PFs on gait patterns and tounderline the need of a dorsal stop in case of PF weakness.
Too weak or prolonged PFs can be responsible for an inactive forefoot lever.Therefore, KAFOs should always be produced using ankle joints withadjustable dorsal stops (fig. 2).
How to check the correct dorsal stop position on the work bench:
1) Press the KAFO with foot piece into the designated shoe.2) Put the KAFO shell into dorsal stop position. The line of gravity should pass through the middle of the femoral shell and ventrally ahead of the ankle joint. The KAFO should stand unassisted.
How to check on your patient:
Stable balance efficacy can bevisualised by slightly leaningthe body‘s centre of gravityforwards and backwards (fig. 3 a).
For the visualisation of acorrect dorsal stop in adynamic situation check if yourpatient achieves a heel rise interminal stance (fig. 3 b).
Fig. 2: Ankle joints with individually adjustable range of motion and dorsal stop in form of anankle joint with an adjustable dynamic dorsiflexion stop (a) or in form of an ankle joint withan adjustable hard dorsiflexion stop (b) built in a stance control KAFO (c).
Tab. 1: Effects of inactive and active forefoot lever on gait parameters to achieve stable balance.
Fig. 3: Visualisation of the KAFO’s dorsal stop on thepatient in a static (a) and a dynamic situation (b).
The biomechanics and gait patterns of healthy patients and a patient withweak PFs have been considered, including an evaluation of worn KAFOs.
PF weakness causes inactivation of the forefoot lever (fig. 1). The activationof the forefoot lever is needed to achieve stable balance (tab. 1).
Fig. 1: Knee and ankle kinematics of a patient with PF weakness (dotted line) wearing a KAFOwith a wrong dorsal stop (DS; dashed line) and with a correct dorsal stop (DS; solid line)compared to a physiological reference group (grey band). The vertical lines represent the heel off.
normal PFs
0-40
100 [% GC]
-40
30/-30
80
Plant
Ankl
e
Dors
Ext
Flex
Knee
[°]
[°]
w KAFO, correct DS w KAFO, wrong DS w/o KAFO, weak PFs
Literature
[1] Beekmann C, Perry J, Boyd LA, Newsam CJ, Mulroy SJ. Topics in Spinal Cord Injury Rehabilitation. 2000; 5(4): 54–62[2] Ploeger HE, Bus SA, Brehm MA, Nollet F. Gait and Posture. 2014; 40(3): 391–398[3] Mulroy SJ, Eberly VJ, Gronley JK, Weiss W, Newsam SJ. Prosthetics and Orthotics International. 2010; 34(3): 277–292
Background and Aim
Materials and Methods
Results
Discussion and Conclusion
Results
Conclusion: A correctly adjusted dorsal stop is absolutely necessary for allorthoses for patients with paralyses and weak PFs to provide safety whilestanding and to improve gait pattern.
Inactive forefoot lever
Security decreased increasedStep length decreased longer
Contralateral knee flexion increased physiologicalTerminal stance
a c5° 15°
b
Heel remains on the floor lifts from the groundBody‘s centre of gravity too low correct
Active forefoot lever
w/o KAFO, weak PFsw KAFO, wrong DSw KAFO, correct DSnormal PFs
a b
2°4°
6°8°10°
15°20°
This poster was presented at the 15th ISPO world congress in Lyon, France, 22nd - 25th June 2015.
PR83
06-D
E/G
B-09
/201
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