What is the management of a complete Anterior Cruciate Ligament (ACL) tear?

Management of Complete ACL Tear

For acute complete ACL tears requiring surgery, early reconstruction (within 3 months) is strongly preferred to prevent additional meniscal and cartilage damage, with reconstruction rather than repair being the definitive surgical approach due to lower revision rates. 1

Initial Assessment and Decision-Making

Acute Management

• Consider aspirating painful, tense knee effusions after injury for symptom relief 1
• MRI is the gold standard for diagnosis with 96% sensitivity and 97% specificity on 3T equipment 2

Treatment Pathway Selection

The decision between surgical and non-surgical management depends primarily on patient age, activity level, and functional demands:

• Younger patients (<30 years) with vigorous physical activity: Early ACL reconstruction is preferable to provide knee stability and protect menisci from subsequent injuries 2
• Active patients of any age: ACL reconstruction should be considered to lower the risk of future meniscus pathology or procedures and may improve long-term pain and function 1
• Less active or older patients: Rehabilitation as first-line treatment can be considered, with reconstruction reserved for those who develop functional instability 3

Surgical Management

Timing of Surgery

When surgery is indicated for acute isolated ACL tear, early reconstruction (within 3 months) is strongly recommended because the risk of additional cartilage and meniscal injury starts to increase after this timeframe 1, 2

Surgical Technique

Reconstruction vs. Repair:

• ACL tears indicated for surgery should be treated with reconstruction rather than repair due to lower risk of revision surgery 1

Bundle Technique:

• Single-bundle or double-bundle techniques can be considered as outcomes are similar (Strong recommendation) 1

Graft Selection

For skeletally mature patients, graft choice involves trade-offs:

• Bone-patellar tendon-bone (BTB) autograft: Favor this to reduce risk of graft failure or infection 1, 2
• Hamstring tendon autograft: Favor this to reduce risk of anterior knee pain or kneeling pain 1, 2

Special consideration for hamstring grafts:

• Anterior lateral ligament (ALL) reconstruction or lateral extra-articular tenodesis (LET) could be considered when performing hamstring autograft reconstruction in select patients to reduce graft failure and improve short-term function 1

Concomitant Injuries

Combined ACL/MCL tears:

• Non-surgical treatment of the MCL injury results in good patient outcomes, though surgical treatment of the MCL may be considered in select cases 1

Meniscal injuries:

• Meniscal repair should be the first option whenever technically possible, as it results in similar clinical outcomes to isolated ACL injuries, unlike meniscectomy 2
• Partial meniscectomy increases osteoarthritis risk (OR=1.87), while total medial meniscectomy presents even higher risk (OR=3.14) 2

Rehabilitation Protocol

Postoperative Rehabilitation Phases

The rehabilitation must be criterion-based rather than time-based alone:

• Adequate rehabilitation is fundamental, including open and closed kinetic chain exercises for quadriceps strength recovery 2
• Training of strength and motor control should be combined in the rehabilitation protocol 2
• When concomitant lesions (meniscal, cartilage) are present, the initial rehabilitation phase should be adapted according to surgeon instructions 2
• The complete rehabilitation protocol should be based on progression criteria, considering time since surgery as necessary but not sufficient for progression unless combined with objective physical and psychological criteria 2

Key rehabilitation principles:

• Less intensive supervised rehabilitation may be a viable solution for patients with limited access to physical therapy 2
• Patient adherence is one of the greatest challenges, and expectations should be discussed ideally before surgery 2

Bracing

Functional knee braces are NOT recommended for routine use in patients who received isolated primary ACL reconstruction because they confer no clinical benefit 1, 2

Return to Sport

Functional evaluation, such as the hop test, may be considered as one factor to determine return to sport after ACL reconstruction 1

• The operated leg should have at least 75% of the strength and power of the normal leg before initiating running 4
• Return to sport should be gradual, advancing from skill drills 4
• Maintenance program should consist of triweekly strength-building sessions and avoidance of high-risk activities 4

Long-Term Considerations

Osteoarthritis Prevention

• Address modifiable risk factors for non-traumatic osteoarthritis (weight control and quadriceps strengthening) after knee injuries 2
• Even with successful surgical treatment, patients with ACL tears have an increased risk of developing knee osteoarthritis long-term 2
• The presence of minor osteoarthritic changes does not influence the treatment decision-making process 2

Prevention of Primary ACL Injuries

• Training programs designed to prevent injury can be used to reduce the risk of primary ACL injuries in athletes participating in high-risk sports 1
• Prophylactic bracing is NOT a preferred option to prevent ACL injury 1