Anterior-cruciate-ligament reconstruction does not alter the knee-extensor moment arm during gait.
Patellar tendon
Patellofemoral
Screw axis
Tibiofemoral
Walking
Journal
Gait & posture
ISSN: 1879-2219
Titre abrégé: Gait Posture
Pays: England
ID NLM: 9416830
Informations de publication
Date de publication:
10 2022
10 2022
Historique:
received:
31
03
2022
revised:
15
08
2022
accepted:
15
09
2022
pubmed:
25
10
2022
medline:
30
11
2022
entrez:
24
10
2022
Statut:
ppublish
Résumé
The ability of the quadriceps muscles to extend the knee depends on the moment arm of the knee-extensor mechanism, which is described by the moment arm of the patellar tendon at the knee. The knee-extensor moment may be altered by a change in quadriceps force, a change in the patellar tendon moment arm (PTMA), or both. A change in quadriceps muscle strength after anterior-cruciate-ligament-reconstruction (ACLR) surgery is well documented, however, there is limited knowledge about how this procedure affects the PTMA. Does ACLR surgery alter the moment arm of the knee-extensor mechanism during gait? We measured the PTMA in both the ACLR knee and the uninjured contralateral knee in 10 young active individuals after unilateral ACLR surgery. Mobile biplane X-ray imaging was used to measure the three-dimensional positions of the femur, tibia and patella during level walking and downhill walking over ground. The PTMA was found from the location of the instantaneous axis of rotation at the knee and the line-of-action of the patellar tendon. There was a small but statistically significant difference in the mean PTMA calculated over one cycle of level walking between the ACLR knee and the contralateral knee, with the mean PTMA in the ACLR knee being 1.5 mm larger (p < 0.01). In downhill walking, statistically significant differences were found in the range 15°- 25° of knee flexion, where the PTMA was 4.7 mm larger in the ACLR knee compared to the contralateral knee (p < 0.01). Significant differences were evident in the mean PTMA between the ACLR knee and the contralateral knee in both activities, however, the magnitudes of these differences were relatively small (range: 3-10%), indicating that ACLR surgery successfully restores the moment arm of the knee-extensor mechanism during dynamic activity.
Sections du résumé
BACKGROUND
The ability of the quadriceps muscles to extend the knee depends on the moment arm of the knee-extensor mechanism, which is described by the moment arm of the patellar tendon at the knee. The knee-extensor moment may be altered by a change in quadriceps force, a change in the patellar tendon moment arm (PTMA), or both. A change in quadriceps muscle strength after anterior-cruciate-ligament-reconstruction (ACLR) surgery is well documented, however, there is limited knowledge about how this procedure affects the PTMA.
RESEARCH QUESTION
Does ACLR surgery alter the moment arm of the knee-extensor mechanism during gait?
METHODS
We measured the PTMA in both the ACLR knee and the uninjured contralateral knee in 10 young active individuals after unilateral ACLR surgery. Mobile biplane X-ray imaging was used to measure the three-dimensional positions of the femur, tibia and patella during level walking and downhill walking over ground. The PTMA was found from the location of the instantaneous axis of rotation at the knee and the line-of-action of the patellar tendon.
RESULTS
There was a small but statistically significant difference in the mean PTMA calculated over one cycle of level walking between the ACLR knee and the contralateral knee, with the mean PTMA in the ACLR knee being 1.5 mm larger (p < 0.01). In downhill walking, statistically significant differences were found in the range 15°- 25° of knee flexion, where the PTMA was 4.7 mm larger in the ACLR knee compared to the contralateral knee (p < 0.01).
SIGNIFICANCE
Significant differences were evident in the mean PTMA between the ACLR knee and the contralateral knee in both activities, however, the magnitudes of these differences were relatively small (range: 3-10%), indicating that ACLR surgery successfully restores the moment arm of the knee-extensor mechanism during dynamic activity.
Identifiants
pubmed: 36274470
pii: S0966-6362(22)00578-1
doi: 10.1016/j.gaitpost.2022.09.074
pii:
doi:
Substances chimiques
3-hydroxyphenyltrimethylammonium
3483-84-9
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
330-336Informations de copyright
Copyright © 2022 Elsevier B.V. All rights reserved.
Déclaration de conflit d'intérêts
Conflict of interest The authors do not have any financial or personal relationships with other people or organizations that could inappropriately influence this manuscript.