Effects of prosthesis alignment on pressure distribution at the stump/socket interface in transtibial amputees during unsupported stance and gait.
OBJECTIVE
To assess the effects of antero-posterior realignment of the prosthesis on pressure distribution at the stump/socket interface in unilateral transtibial amputees during unsupported stance and gait.


METHODS
Cross-sectional group study.


METHODS
Outpatient rehabilitation clinic.


METHODS
Seventeen unilateral transtibial amputees.


METHODS
Antero-posterior prosthesis realignment using 0.5 cm heel or forefoot wedging.


METHODS
Pressure distribution changes at several sites at the stump/socket interface, expressed as peak pressure, peak pressure time, sustained submaximal load (MP80+) and time period of MP80+ (TP80+).


RESULTS
During stance, heel wedging led to a 30.4% decrease in mean pressure near the patella tendon and a 40.0% increase near the distal tibia site, whereas forefoot wedging led to a 30.0% decrease in pressure in the tibial end region. Antero-posterior ankle realignment did not lead to significant changes near the fibular head. During gait only heel wedging led to a 11.5% increase in peak pressure in the tibia end region. Mean peak pressure time increased 22.7% using heel wedging and decreased 8.8% using forefoot wedging. MP80+ increased 23.8% in the tibia end region during heel wedging and 17.0% in the subpatellar region during forefoot wedging.


CONCLUSIONS
Antero-posterior realignment of the ankle joint led to an inverse loading and unloading of the subpatellar region versus tibial end region. However, results indicate that stump/socket interface pressure during stance seems not to be highly predictive as to pressure behaviour during gait. Ankle joint realignment led to significant differences in temporal sequences of tissue (un-)loading in the subpatellar area during gait.
Seelen
H A M
HA
Rehabilitation Foundation Limburg, The Netherlands. ham.seelen@irv.nl
Anemaat
S
S
Janssen
H M H
HM
Deckers
J H M
JH
D000671:Amputation, Surgical / Q000534:rehabilitation*; D000672:Amputation Stumps / Q000503:physiopathology*; D000843:Ankle Joint / Q000503:physiopathology; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D005260:Female; D005360:Fibula / Q000503:physiopathology; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg; D008297:Male; D008875:Middle Aged; D010329:Patella / Q000503:physiopathology; D011187:Posture / Q000502:physiology; D011312:Pressure; D013977:Tibia / Q000503:physiopathology