Motion alterations after anterior cruciate ligament reconstruction: comparison of the injured and uninjured lower limbs during a single-legged jump.
BACKGROUND
Asymmetries subsist after anterior cruciate ligament reconstruction (ACL-R), and it is unclear how lower limb motion is altered in the context of a dynamic movement.


OBJECTIVE
To highlight the alterations observed in the injured limb (IL) during the performance of a dynamic movement after ACL-R.


METHODS
Cross-sectional study.


METHODS
Research laboratory.


METHODS
A total of 11 men (age = 23.3 ± 3.8 years, mass = 81.2 ± 17.0 kg) who underwent ACL-R took part in this study 7.3 ± 1.1 months (range = 6-9 months) after surgery.


METHODS
Kinematic and kinetic analyses of a single-legged squat jump were performed. The uninjured leg (UL) was used as the control variable.


METHODS
Kinematic and kinetic variables.


RESULTS
Jump height was 24% less for the IL than the UL (F1,9 = 23.3, P = .001), whereas the push-off phase duration was similar for both lower limbs (P = .96). Knee-joint extension (F₁,₉ = 11.4, P = .009), and ankle plantar flexion (F₁,₉ = 22.6, P = .001) were less at takeoff for the IL than the UL. The hip angle at takeoff was not different between lower limbs (P = .09). We found that total moment was 14% less (F₁,₉ = 11.1, P = .01) and total power was 35% less (F₁,₉ = 24.2, P = .001) for the IL than the UL. Maximal hip (P = .09) and knee (P = .21) power was not different between legs. The IL had 34% less maximal ankle power (F₁,₉ = 11.3, P = .009) and 31% less angular velocity of ankle plantar flexion (F₁,₉ = 17.8, P = .004) than the UL.


CONCLUSIONS
At 7.3 months after ACL-R, motion alterations were present in the IL, leading to a decrease in dynamic movement performance. Enhancing the tools for assessing articular and muscular variables during a multijoint movement would help to individualize rehabilitation protocols after ACL-R.
Université de Lyon-Université Claude Bernard, France.
Benoît Pairot
BP
de Fontenay
Sebastien
S
Argaud
Yoann
Y
Blache
Karine
K
Monteil
D000328:Adult; D000704:Analysis of Variance; D000842:Ankle / Q000503:physiopathology; D000843:Ankle Joint / Q000503:physiopathology; D016118:Anterior Cruciate Ligament / Q000503:physiopathology* / Q000601:surgery; D059549:Anterior Cruciate Ligament Reconstruction / Q000534:rehabilitation*; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D015444:Exercise; D006801:Humans; D007717:Knee / Q000503:physiopathology* / Q000601:surgery; D007718:Knee Injuries / Q000503:physiopathology / Q000601:surgery; D007866:Leg / Q000503:physiopathology; D008297:Male; D009038:Motion; D009068:Movement / Q000502:physiology*; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology* / Q000534:rehabilitation; D016059:Range of Motion, Articular; D020127:Recovery of Function / Q000502:physiology*; D013177:Sports / Q000502:physiology*; D055815:Young Adult
dynamic movement; hop test; knee; rehabilitation