What is the treatment plan for a patient with an anterior cruciate ligament (ACL) partial tear?

Treatment Plan for ACL Partial Tear

For patients with a partial ACL tear, initial non-surgical management with structured rehabilitation is recommended, with surgical intervention reserved for those who experience functional instability despite conservative treatment. 1, 2

Initial Assessment and Management

• Aspiration of painful, tense effusions may be considered after knee injury with ACL tear 1
• Immediate weight bearing is safe as long as:
  • Correct gait pattern is maintained (with crutches if needed)
  • No pain, effusion, or increased temperature when walking 1
• Cryotherapy can be applied in the first postoperative week to reduce pain 1

Non-Surgical Management (First-Line Approach)

Non-surgical treatment is appropriate for partial ACL tears that demonstrate stability on clinical examination, as these have good outcomes with conservative management 3, 4.

Rehabilitation Protocol:

1. Week 1:

   • Begin isometric quadriceps exercises for muscle reactivation (when pain-free) 1
   • Consider electrostimulation to re-educate voluntary quadriceps contraction 1

2. Week 2 onwards:

   • Progress to concentric and eccentric exercises when quadriceps is reactivated
   • Start closed kinetic chain (CKC) exercises 1

3. Week 4 onwards:

   • Begin open kinetic chain (OKC) exercises in restricted ROM (90-45°) 1
   • Gradually increase ROM: 90-30° in week 5,90-20° in week 6,90-10° in week 7, full ROM in week 8 1

4. Throughout rehabilitation:

   • Add neuromuscular training to strength training to optimize outcomes 1
   • Monitor for signs of instability that may indicate need for surgical intervention 2
   • Continue rehabilitation for 9-12 months depending on return-to-work/play goals 1

Surgical Management (When Indicated)

Surgical intervention should be considered if:

• Patient experiences functional instability despite rehabilitation
• Patient is young and active with high athletic demands
• Evidence of progression to complete tear 5

Surgical Timing:

If surgery is indicated, early reconstruction is preferred as risk of additional cartilage and meniscal injury increases within 3 months of injury 1, 2

Surgical Options:

• Traditional ACL reconstruction is supported by best evidence for nonfunctional partial tears 5
• Autograft is preferred over allograft, particularly in young/active patients 1
• Graft selection considerations:
  • Bone-patellar tendon-bone (BTB) to reduce risk of graft failure
  • Hamstring autograft to reduce risk of anterior/kneeling pain 1, 2

Return to Activity Criteria

Return to activity should be based on functional criteria rather than time alone:

• No pain or swelling
• Full knee ROM
• Stable knee on examination
• Normalized subjective knee function and psychological readiness
• Limb symmetry index (LSI) >90% for quadriceps strength
• Successful completion of sport-specific training program 2

Monitoring and Follow-up

• Regular assessment of knee stability and episodes of giving way
• Evaluation of pain levels and functional outcomes using validated tools
• Assessment of psychological factors, particularly fear of reinjury 2

Important Considerations

• 92% of international ACL experts recommend non-operative management for partial ACL tears that are stable on examination 4
• Partial ACL tears have better outcomes with conservative treatment compared to complete tears 3
• The risk of progression to complete tear is higher in younger, more active patients 5
• Untreated functionally unstable ACL tears significantly increase risk of additional cartilage and meniscal injury 2