Non-Surgical Treatment Approach for Anterior Cruciate Ligament (ACL) Injuries
Non-surgical treatment with physical therapy and activity modification is the recommended first-line approach for ACL injuries in older patients with lower activity levels, as it allows patients to minimize functional instability while avoiding the risks associated with surgery. 1
Patient Selection for Non-Surgical Management
The decision between surgical and non-surgical management depends on several key factors:
Age and Activity Level Considerations
- Younger patients (<30 years): Early ACL reconstruction is often recommended for those participating in high-level activities 1
- Older patients (>40 years): Non-surgical management is typically more appropriate 1
- Activity demands: Lower activity levels are better tolerated in ACL-deficient knees 1
Factors Favoring Non-Surgical Treatment
- Older age
- Female sex
- Good knee function on initial assessment
- Higher scores on knee function questionnaires (KOOS, KOS-ADLS) 2
- Good performance on single-leg hop tests 2
- No significant instability episodes after initial injury 3
- No concomitant ligament or meniscal damage 3
Components of Non-Surgical Treatment
1. Initial Phase (Acute Management)
- RICE protocol (Rest, Ice, Compression, Elevation)
- Pain management
- Early range of motion exercises
- Progressive weight-bearing as tolerated
- Gait training
2. Rehabilitation Program
Three primary non-surgical approaches are considered appropriate by the American Academy of Orthopaedic Surgeons 1:
- Self-directed exercise program (rated 7/9 for appropriateness)
- Supervised rehabilitation program (rated 7/9 for appropriateness)
- Activity modification without reconstruction (rated 7/9 for appropriateness)
3. Comprehensive Rehabilitation Components
- Lower extremity strength training: Focus on quadriceps, hamstrings, and core muscles 3
- Cardiovascular endurance training 3
- Neuromuscular training: Balance and proprioception exercises 3
- Agility and sport-specific skill training 3
- Balance perturbation training: To improve dynamic stability 3
Functional Bracing
ACL functional knee bracing without reconstruction is considered "May Be Appropriate" (rated 5-6/9) by the AAOS 1. While not definitively recommended for all patients, it may provide additional support during the rehabilitation process or return to activities.
Monitoring and Follow-Up
Regular assessment of:
- Knee stability
- Episodes of giving way
- Return to desired activity level
- Pain levels
- Functional outcomes using validated tools (KOOS, IKDC)
Outcomes and Prognosis
- Approximately 54% of highly active patients with ACL injury who choose non-surgical treatment have successful 2-year outcomes 2
- The ACL SNNAP trial showed that surgical reconstruction was clinically superior to rehabilitation alone for non-acute ACL injuries with persistent symptoms of instability 4
- 41% of patients initially managed non-surgically eventually required surgery within 18 months 4
When to Consider Delayed Surgical Intervention
Non-surgical treatment may fail, requiring delayed ACL reconstruction if:
- Persistent instability develops despite rehabilitation 1
- Patient experiences recurrent giving way episodes 1
- Patient wishes to return to high-demand pivoting sports 5
- Development of secondary meniscal or cartilage damage 1
Cautions and Pitfalls
- Underestimating rehabilitation requirements: Successful non-surgical management requires dedicated adherence to rehabilitation protocols
- Inappropriate patient selection: Patients with high activity demands may have poorer outcomes with non-surgical management
- Delayed recognition of treatment failure: Persistent instability should prompt timely reconsideration of surgical options
- Ignoring concomitant injuries: Meniscal tears or other ligament injuries may require different management approaches
- Inadequate follow-up: Regular assessment is needed to identify those who may need to transition to surgical management
Non-surgical management should be considered a trial of conservative care, with the understanding that delayed surgical reconstruction remains an option if functional stability cannot be achieved through rehabilitation alone.