Korean J Sports Med.  2024 Jun;42(2):67-85. 10.5763/kjsm.2024.42.2.67.

Functional Recovery Program before and after Anterior Cruciate Ligament Reconstruction: A Current Concepts Review

• Cho SI
• Yang SJ
• Park BS
• Kong DH
• Lee JW
• Lee DW

• KMID: 2556272
• DOI: http://doi.org/10.5763/kjsm.2024.42.2.67

Abstract

Anterior cruciate ligament (ACL) rupture leads to weakened quadriceps muscle strength and a decline in proprioception, impairing the neuromuscular control of the lower extremities. ACL reconstruction, aimed at addressing such structural and functional instability, has become a primary treatment method for young and active patients. Consequently, there have been significant advancements in surgical techniques, resulting in improved clinical outcomes. However, achieving successful outcomes after ACL reconstruction is not solely dependent on the surgery itself; pre- and postoperative rehabilitation and management are equally crucial. A well-designed functional recovery program based on medical evidence before and after ACL reconstruction plays a vital role in restoring function to preinjury levels. The process of the functional recovery program, from presurgery to sports return, should adhere to certain principles. These principles involve prompt and accurate clinical diagnosis and patient classification after injury, systematic programs addressing joint swelling and inflammation control, reduction of arthrogenic muscle inhibition, restoration of range of motion, muscle strength recovery, and proprioception restoration. Postoperatively, it is essential to go beyond traditional methods (such as range of motion restoration and muscle strengthening) by implementing a functional recovery program that includes enhancement of proprioception and neuromuscular control system from the early stages, considering the biological healing response of the graft. This comprehensive approach is vital for achieving optimal outcomes in the recovery of function after ACL reconstruction.

Keyword

Anterior cruciate ligament; Anterior cruciate ligament reconstruction; Rehabilitation; Arthrogenic muscle inhibition; Proprioception

Figure

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  Fig. 1 Weight shifting.

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  Fig. 2 Ice and compression.

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  Fig. 3 Extension deficit.

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  Fig. 4 Exercises for knee extension. (A) Hanging weight exercise. (B) Active terminal knee extension exercise.

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  Fig. 5 Exercises for knee flexion. (A) Knee sliding exercise with a towel. (B) Wall sliding exercise.

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  Fig. 6 Mechanisms of arthrogenic muscle inhibition.

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  Fig. 7 Interventions for arthrogenic muscle inhibition. (A) Isometric hamstring fatigue exercise. (B) Prone quadricep (Q)-setting exercise. (C) Q-muscle activation with neuromuscular electrical stimulation.

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  Fig. 8 Closed kinetic chain (CKC) and open kinetic chain (OKC) exercises for muscle strength recovery. (A) CKC exercise: mini squat (0° to 45° knee flexion). (B) OKC exercise: leg extension (90° to 30° knee extension).

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  Fig. 9 Neuromuscular training for proprioception. (A) Single leg stance on an unstable surface. (B) Balance exercise against valgus force.

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  Fig. 10 Exercises for knee extension. (A) Passive knee extension. (B) Patellar mobilization. (C) Quadricep set exercise.

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  Fig. 11 Passive knee extension over press for overcoming knee extension deficit.

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  Fig. 12 Early-stage range of motion (ROM) exercises. (A) Passive knee ROM exercise. (B) Active-assisted knee ROM exercise.

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  Fig. 13 Treatments of arthrogenic muscle inhibition. (A) Neuromuscular electrical stimulation. (B) Blood flow restriction training.

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  Fig. 14 Stages for knee flexor strengthening after anterior cruciate ligament reconstruction. (A) Stage I (3–5 weeks): squat (co-contraction). (B) Stage II (6–8 weeks): active leg curl without resistance (concentric). (C) Stage III (9–12 weeks): leg curl with resistance (concentric). (D) Stage IV (3–5 months): Romanian deadlift (eccentric). (E) Stage V (from 6 months): nordic hamstring curl (eccentric).

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  Fig. 15 Exercises for the muscles around the ankle and hip joints. (A) Calf raise exercise. (B) Hip abduction exercise. (C) Clamshell exercise.

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  Fig. 16 Stages for proprioceptive training after anterior cruciate ligament reconstruction. (A) Stage I (0–3 weeks): weight shifting. (B) Stage II (4–5 weeks): mini squats on the balance board. (C) Stage III (6–7 weeks): single leg balance on an unstable surface (low grade). (D) Stage IV (8–12 weeks): single leg balance on an unstable surface (high grade). (E) Stage V (from 3 months): perturbation training.

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