Sustained Limb-Level Loading: A Ground Reaction Force Phenotype Common to Individuals at High Risk for and Those With...

Area of Science:

• Biomechanics
• Orthopedics
• Sports Medicine

Background:

• Anterior cruciate ligament reconstruction (ACLR) can alter lower limb biomechanics.
• Knee osteoarthritis (KOA) involves progressive joint degeneration and associated gait changes.
• Understanding ground reaction force (GRF) profiles is crucial for evaluating gait in these populations.

Purpose of the Study:

• To compare vertical (vGRF), anterior-posterior (apGRF), and medial-lateral (mlGRF) GRF profiles during gait.
• To compare individuals 6-12 months post-ACLR with uninjured controls.
• To compare individuals 6-12 months post-ACLR with varying Kellgren and Lawrence (KL) grades of KOA (KL2, KL3, KL4).

Main Methods:

• Retrospective cross-sectional analysis of 196 participants.
• Gait biomechanics data collected from ACLR (n=36), controls (n=36), KL2 (n=31), KL3 (n=67), and KL4 (n=26) KOA groups.
• Functional linear models used to assess between-group differences in GRF profiles throughout stance phase.

Main Results:

• ACLR group showed lower vGRF and apGRF than controls in early/late stance (large effects).
• ACLR group had greater vGRF and apGRF than KL2 KOA group in late stance.
• GRF profile differences between ACLR and KOA groups increased with KOA severity; no mlGRF differences found between ACLR and controls or KL2 KOA.

Conclusions:

• Individuals 6-12 months post-ACLR exhibit GRF profiles similar to those with KL2 KOA.
• Both ACLR and KL2 KOA patient groups may benefit from interventions addressing aberrant GRF profiles.
• These findings highlight potential commonalities in gait dysfunction between ACLR and early KOA.