The second part of the series outlining ACL rehab.

Mid-Stage ACL Rehabilitation: Building Strength, Stability, and Confidence

Mid-stage rehabilitation following an Anterior Cruciate Ligament (ACL) surgery is a critical period where patients transition from initial healing to regaining strength, stability, and function. This phase focuses on more dynamic exercises and begins to prepare the individual for eventual return to sport and daily activities. One of the key goals during this stage is to ensure the knee can handle various loads and movements without pain or swelling, setting a solid foundation for more advanced activities.

1. Quadriceps Strength: A Cornerstone of Recovery

A vital component of mid-stage ACL rehabilitation is the focus on quadriceps strength. The quadriceps muscle plays a significant role in stabilizing the knee, and its strength is a good predictor of successful outcomes post-ACL reconstruction. One method to measure this strength is through quadriceps testing for torque normalized to body weight. This involves using specialized equipment called a dynamometer to assess the force the quadriceps can produce, comparing it to the patient’s body weight to ensure the muscle’s strength is proportional and adequate for safe and effective movement patterns.

2. Advanced Testing: Squat, Jump, and Heel Raise Endurance

As strength and healing progress, it’s essential to assess how the knee responds to more dynamic and challenging activities. This is where force plate squat and jump testing come into play. Impulse PT uses Kinvent force plates for this testing. These tests measure how the knee handles loads during squatting and jumping movements, providing valuable data on the joint’s readiness for sports-related activities. It’s crucial for these measurements to indicate symmetrical and appropriate force distribution, ensuring the injured knee can withstand similar pressures as the uninjured side.

Additionally, heel raise endurance testing is employed to assess calf muscle strength and endurance, another critical factor for safe return to running and sports. This test evaluates the ability to perform repeated heel raises without fatigue, indicating lower limb readiness for the demands of running and jumping.

3. Continuing Neuromuscular Electrical Stimulation (NMES)

Neuromuscular electrical stimulation (NMES) remains a valuable tool during mid-stage rehab. NMES helps to improve muscle activation and strength by stimulating the quadriceps muscle, aiding in overcoming the inhibition often seen after knee surgery. This continued use of NMES supports muscle growth and re-education, reinforcing the gains made in muscle strength during this crucial recovery phase.

4. The Role of Open Chain Exercises

The inclusion of open chain exercises, like those performed on a leg extension machine, is absolutely critical in mid-stage rehabilitation. Despite some controversy, these exercises provide targeted strengthening for the quadriceps without placing undue stress on the ACL graft. It’s important to integrate these carefully monitored exercises to ensure the quadriceps muscle regains its pre-injury strength and functionality, essential for stabilizing the knee during all activities.

5. Starting to run again

Return to running after ACLR can be a tricky process to dial in without getting an increase in swelling or soreness. Typically this can begin at 12 weeks, but more commonly closer to 16 weeks is more appropriate to make sure that adequate quadriceps strength and other criteria is met, and that we are not avoiding using the quadriceps when running by keeping a stiff knee. Once starting to run, a return to run program is helpful to make sure we are not overloading the knee with too much volume, too fast. Typically this looks like a walk to jog progression over the course of a month or two.

Conclusion

Mid-stage ACL rehabilitation marks a pivotal point in the recovery journey, focusing on building the strength, stability, and confidence needed to return to everyday activities and sports. By carefully assessing and improving quadriceps strength, utilizing advanced testing methods to gauge readiness for dynamic movements, continuing the use of NMES, and incorporating open chain exercises, patients can make significant strides towards a successful recovery. The goal is to ensure the knee is not only healed but also strong and capable of handling the rigors of sports and daily life, setting the stage for a successful return to sport in the final phase of rehabilitation.