Why Tensionless Repair is Critical in Meniscus Root Repair
A tensionless repair is essential in meniscus root repair because it prevents mismatch between the intra- and extracapsular distances when reducing the meniscus to its anatomic position, which is the key to successful healing and restoration of meniscal hoop tension. 1
The Biomechanical Rationale
- Meniscus root tears disrupt the circumferential fiber continuity, causing complete loss of the meniscus's ability to convert axial loads into transverse hoop stresses 2
- Root tears functionally equivalent to total meniscectomy in terms of biomechanical consequences, as the meniscus can no longer distribute load properly across the joint 3, 2
- Restoration of hoop tension requires anatomic reduction of the meniscus back to its original footprint without creating tension that would pull the repair apart 1
Technical Execution of Tensionless Repair
- Anatomic reduction is the foundation: The meniscus must first be reduced to its exact anatomic position on the tibial plateau before any repair sutures are placed 1
- Traction stitches facilitate reduction: All-inside suture devices can be used to place traction stitches that help pull the meniscus back to its anatomic position without creating excessive tension 1
- Capsular fixation precedes tear repair: Once anatomically reduced, the meniscus should be repaired to the capsule using vertical mattress sutures (all-inside or inside-out techniques) to maintain the anatomic position 1
- Rip-stop sutures complete the repair: Horizontal or oblique sutures are then placed across the actual tear site to close the defect, but only after the meniscus is already held in its proper position 1
Why Tension Creates Failure
- Adjustable fixation devices demonstrate the importance of proper tensioning: Recent biomechanical studies show that adjustable suture anchor-based fixation with controlled tension (80-120 N) achieves higher initial repair strength and reduces displacement during cyclic loading compared to traditional fixed repairs 4
- Excessive tension causes gap formation: If the repair is under tension, cyclic loading during normal activities will progressively pull the meniscus away from its attachment site 4
- Mismatch prevention is critical: When the meniscus is not anatomically reduced before repair, the distance from the tear site to the capsule differs from the intra-articular to extra-articular path, creating inherent tension that dooms the repair 1
Clinical Implications
- Transtibial pull-out techniques allow broad footprint fixation: These techniques enable reduction and fixation of the meniscal root to its anatomic footprint, maximizing healing potential while maintaining a tensionless state 2
- Biological factors are enhanced: The transtibial tunnels may release biological factors that enhance healing, but only if the repair is tensionless enough to allow tissue apposition 2
- Superior outcomes require proper technique: Meniscal root repair demonstrates high satisfaction rates and superior outcomes compared to meniscectomy, but only when executed with proper tensionless technique 2