What is the treatment for an oblique superior articular surface tear of the anterior horn of the lateral meniscus?

Treatment of Oblique Superior Articular Surface Tear of the Anterior Horn Lateral Meniscus

For an oblique superior articular surface tear of the anterior horn of the lateral meniscus, arthroscopic repair is strongly recommended over partial meniscectomy to preserve meniscal function and prevent long-term joint deterioration.

Diagnosis and Assessment

• MRI is the gold standard for diagnosing meniscal tears with 96% sensitivity and 97% specificity at 3T, allowing precise characterization of tear patterns 1
• Oblique superior articular surface tears of the anterior horn lateral meniscus are best visualized through a modified anteromedial portal during arthroscopy 2
• These tears may be accompanied by local parameniscal cysts that require debridement prior to repair 3

Treatment Options

Arthroscopic Repair (Recommended)

• All-inside repair techniques using absorbable sutures are effective for anterior horn tears of the lateral meniscus 2
• For tears accompanied by parameniscal cysts, suture anchor repair is recommended after cyst debridement to secure the anterior horn to the anterolateral tibial plateau 3
• Repair techniques include:
  • Vertical suture placement across the tear 2
  • Suture anchor fixation for tears with significant tissue loss after cyst debridement 3
  • Additional suturing to surrounding synovium to promote healing 3

Partial Meniscectomy (Not Recommended)

• Biomechanical studies show that partial meniscectomy significantly decreases contact area and increases peak contact pressure in the knee joint 4
• At 0° knee flexion, contact area decreases to 65.4% of normal after inferior leaf resection and 50.5% after both leaf resection 4
• Peak pressure increases to 127-139% after inferior leaf resection and 139-156% after both leaf resection 4
• These biomechanical changes are associated with accelerated cartilage damage and osteoarthritis 4

Outcomes and Prognosis

• Complete healing rates of 80.3% have been reported for lateral meniscus oblique radial tears after repair 5
• Significant improvements in patient-reported outcomes are observed after repair, with Lysholm scores improving from 64.1 preoperatively to 88.2 postoperatively 5
• International Knee Documentation Committee subjective scores improve from 50.5 to 82.9 after repair 5
• Preserving meniscal tissue is crucial for maintaining normal knee biomechanics and preventing early-onset osteoarthritis 6

Special Considerations

• If the tear is associated with an ACL injury (common scenario), concurrent ACL reconstruction and meniscal repair is recommended 6, 5
• The incidence of lateral meniscal tears in acute ACL injuries is approximately 15.3%, with oblique radial tears being among the most common patterns 5
• Early intervention is preferred for meniscal tears associated with ACL injuries, as the risk of additional cartilage damage increases within 3 months of injury 1

Treatment Algorithm

1. Confirm diagnosis with MRI 1
2. Assess tear pattern and location arthroscopically 2
3. Evaluate for associated injuries (especially ACL) 6, 5
4. Perform arthroscopic repair using appropriate technique based on tear characteristics:
   • Standard all-inside repair for simple tears 2
   • Suture anchor technique for tears with associated cysts 3
5. Address any concurrent ligamentous injuries (particularly ACL) 1
6. Implement appropriate rehabilitation protocol based on repair technique and associated procedures