From the Guidelines
To achieve full extension after ACL repair, early mobilization and consistent physical therapy exercises targeting knee extension are crucial, as evidenced by the most recent and highest quality study 1. The goal is to regain full extension within 2-4 weeks post-surgery to prevent long-term mobility issues.
Key Exercises
- Heel props: Place a rolled towel under your ankle while lying down, allowing gravity to help straighten your knee for 5-10 minutes several times daily.
- Active terminal knee extensions: Sit with your leg supported, then straighten your knee fully and hold for 5-10 seconds, repeating 10-15 times per session.
- Wall slides: Lie on your back with your foot against a wall and slowly slide your heel down to extend your knee.
Additional Recommendations
- Use ice for 15-20 minutes after exercises to reduce swelling, which can limit extension 1.
- Take prescribed anti-inflammatory medications like ibuprofen (400-600mg three times daily with food) if recommended by your doctor.
- Prioritize extension exercises in the first 2-3 weeks post-surgery, as scar tissue formation can permanently limit motion if not addressed early 1.
Rehabilitation Guidelines
- Early full weight-bearing exercises and open kinetic chain exercises may be used according to individual circumstances 1.
- Isometric quadriceps exercises, including static quadriceps contractions and straight leg raises, can be safely prescribed during the first 2 postoperative weeks 1.
- Eccentric cycle ergometer training may result in greater strength gains and better daily activity level if initiated at 3 weeks instead of 12 weeks after surgery 1.
From the Research
Achieving Full Extension Post ACL Repair
To achieve full extension post ACL repair, several factors should be considered:
- Early-stage rehabilitation is crucial for successful outcomes, and it involves addressing six main dimensions: pain and swelling, knee joint range of motion, arthrogenic muscle inhibition and muscle strength, movement quality/neuromuscular control, psycho-social-cultural and environmental factors, and physical fitness preservation 2
- Rehabilitation protocols have shifted from conservative, standardized length protocols to more accelerated, individualized protocols that vary in length and modalities based on patient-specific findings and preferences 3
- Early weight bearing, open kinetic chain exercises, and alternative modalities such as neuromuscular electrical stimulation and blood flow restriction have been found to be effective in ACL rehabilitation 3
Role of Continuous Passive Motion
Continuous passive motion (CPM) has been found to have beneficial effects on range of motion, pain, and swelling after ACL reconstruction:
- CPM has been shown to improve knee flexion and reduce pain and swelling in the early postoperative period 4
- However, the therapeutic value of CPM after ACL replacement has been found to be limited, with only a small advantage in rehabilitation 5
- Immediate CPM therapy has been found to produce a superior in situ microenvironment for reducing the occurrence of posttraumatic osteoarthritis after ACL injury without reconstruction in rabbits 6
Key Considerations
When aiming to achieve full extension post ACL repair, the following should be considered:
- Individualized rehabilitation protocols that address patient-specific needs and preferences 3
- Early intervention and addressing the six main dimensions of early-stage rehabilitation 2
- The use of CPM and other alternative modalities to improve range of motion, reduce pain and swelling, and promote overall rehabilitation 4