Persistent knee deficits occurred post-APM, characterized by ankle-dominant braking and hip-dominant propulsion, with limb sequence influencing knee loading such that APM penultimate contact shifted braking to the contralateral limb at final contact.
Key Findings
Results
During the penultimate foot contact of a 90° change-of-direction task, the APM limb showed lower total and knee negative power magnitudes compared to healthy limbs.
Total negative power was lower in APM limbs with a mean difference of 2.80 W/kg (95% CI: 0.59, 5.00)
Knee negative power was lower in APM limbs with a mean difference of 2.60 W/kg (95% CI: 0.75, 4.46)
Data collected from 24 post-APM and 20 healthy individuals using motion capture with force plates
Participants performed a running approach before executing a 90° CoD task
Results
During penultimate contact, the APM limb demonstrated a shift in joint power contributions, with lower knee contribution and higher ankle contribution compared to healthy limbs.
Knee contribution was lower in APM limbs by -10.57% (95% CI: -19.63, -1.52)
Ankle contribution was higher in APM limbs by 10.13% (95% CI: 0.47, 19.79)
This pattern reflects an ankle-dominant braking strategy during the penultimate step
Linear mixed-effects models were used to compare limb differences
Results
During the final foot contact, the APM limb showed lower knee negative power magnitude compared to the contralateral limb.
Knee negative power was lower in APM limbs than contralateral limbs by a mean difference of 0.65 W/kg (95% CI: 0.06, 1.24)
This difference was observed when the APM limb served as the penultimate contact limb, suggesting a cross-step loading relationship
The contralateral limb assumed greater braking load at final contact when the APM limb was used for the penultimate step
Results
Compared with healthy individuals, the APM limb showed lower positive knee and ankle power and altered joint contribution patterns during the final contact.
APM limb showed lower knee contribution by -7.23% (95% CI: -14.19, -0.27) compared to healthy limbs during final contact
APM limb showed greater hip contribution by 9.73% (95% CI: 0.33, 19.13) compared to healthy limbs during final contact
Both positive knee and ankle power were lower in APM limbs compared to healthy limbs
This pattern reflects a hip-dominant propulsion strategy in post-APM individuals
Results
Limb sequence during the change-of-direction task influenced knee loading patterns across steps, with APM penultimate contact shifting braking demands to the contralateral limb at final contact.
A secondary aim examined the relationship between knee negative power at the penultimate and final foot contacts across limb sequences
When the APM limb was used for penultimate contact, the contralateral limb experienced redistributed braking loads at final contact
This cross-step interaction was identified using linear mixed-effects models examining the relationship between steps
The finding suggests that step-specific strategies have implications beyond the individual limb
Discussion
The study identified persistent knee offloading strategies in post-APM individuals during a high-demand 90° change-of-direction task, with compensatory loading redistributed to the ankle and hip.
Knee deficits were characterized by ankle-dominant braking during the penultimate step and hip-dominant propulsion during the final step
These findings extended previously documented knee offloading to a higher-demanding CoD task
The authors suggest rehabilitation approaches may benefit from prioritizing knee function while preparing the ankle and hip to tolerate redistributed loads
Study included 24 post-APM participants and 20 healthy controls
What This Means
This research suggests that people who have had surgery to remove part of their knee meniscus (a cartilage cushion in the knee) continue to protect their operated knee even during complex, high-speed movement tasks like changing direction while running. Specifically, when these individuals made a 90-degree turn, they consistently used their knee less and relied more on their ankle and hip joints to absorb and generate force — a pattern not seen in healthy individuals. This was true both in the step before the turn (the penultimate step) and the final push-off step of the turn itself.
An important additional finding is that how a person sequences their steps during a turn matters. When the operated leg was used for the second-to-last step before the turn, greater braking loads were transferred to the non-operated leg during the final turning step. This means that the way an individual organizes their footwork during a direction change can shift stress between legs in ways that may have consequences for the health of the uninjured limb over time.
This research suggests that rehabilitation programs after meniscus surgery may need to do more than just focus on the operated knee in isolation. Since the ankle and hip are absorbing extra load to compensate for the reduced knee contribution, training these joints to handle redistributed forces could be important. Additionally, practicing direction-change movements with attention to step sequencing may help patients move more symmetrically and reduce the risk of overloading other joints or the non-operated limb.
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Starbuck C, Herrington L, Walters V, Barkatali B, Jones R. (2026). Movement Strategies During the Penultimate and Final Steps of a Change of Direction Following Arthroscopic Partial Meniscectomy.. Scandinavian journal of medicine & science in sports. https://doi.org/10.1111/sms.70367