Landing Mechanics After Ankle Injury
A 16-year-old basketball player returns to full training 10 weeks after a lateral ankle sprain. During a drop-landing assessment from a 40 cm box, he lands with his knees close together and slightly inward, his trunk leaning to the left, and his heels lifting immediately on contact. His left ankle range of motion is 8 degrees less in dorsiflexion than the right. He reports no pain but says he feels 'unsteady' when landing on the left leg. His vertical jump is 48 cm, down from 54 cm before the injury. The coach wants to know whether he is safe to progress to full competition and what biomechanical and motor-learning work should come first.
1. Analyse the landing using biomechanical principles and explain the injury-risk implications.
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The landing shows several linked biomechanical issues. Knees close together and drifting inward indicate insufficient hip abduction and external rotation control, which increases dynamic knee valgus. Valgus loading raises stress on the anterior cruciate ligament and patellofemoral joint, particularly in a player returning from injury. The trunk lean to the left shifts the centre of mass away from the base of support, making balance correction harder and increasing the demand on the left ankle.
Heels lifting immediately on contact means the ankle complex is absorbing less force through dorsiflexion, so the knee and hip must absorb more. The 8-degree dorsiflexion deficit on the left limits how far the knee can travel forward over the foot, which encourages the heel lift and the inward knee position. Reduced vertical jump from 54 cm to 48 cm suggests the left leg is contributing less force. Together these findings indicate the player is not yet safe for full competition, because landing control and force absorption are still compromised.
2. Design a short progression that uses motor-learning principles to improve his landing control, and justify the sequencing.
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Start with the constraint that matters most: controlled deceleration with the knee tracking over the foot. Begin with low-amplitude landings from a 20 cm box, focusing on hip-width stance, knees over toes and a quiet landing, performed at slow speed with explicit cues such as 'spread the floor' and 'land softly'. This is the cognitive stage, so short sets, frequent feedback and simple cues are appropriate. Include ankle mobility work for dorsiflexion before landing practice so the range is available.
Progress to single-leg landings and lateral hop-and-stick tasks once he can hold a stable landing for 3 seconds without heel lift or knee collapse. Use variable practice, such as different directions and heights, to build adaptability rather than a single rehearsed pattern. Reduce feedback frequency as control improves so he learns to use his own sensory information. Only after he demonstrates consistent control under unpredictable conditions, such as reacting to a coach's signal, should he progress to contested rebounding and full competition.