How does FasT-Fix (all-inside meniscal repair device) work?

How the FasT-Fix All-Inside Meniscal Repair Device Works

The FasT-Fix all-inside meniscal repair device works by deploying two small T-shaped anchors connected by a pre-tied, self-sliding knot that creates a vertical or horizontal mattress suture configuration, allowing for effective meniscal repair while avoiding the morbidity associated with traditional inside-out techniques. 1

Mechanism of Action

The FasT-Fix device combines the advantages of traditional inside-out meniscal repair with an all-inside technique, offering several key features:

• Deployment System: The device uses a needle delivery system with two T-shaped anchors (T-Fix bars) connected by a strong suture 2

• Implantation Process:

  • The first anchor is deployed behind the capsule
  • The needle is withdrawn and repositioned
  • The second anchor is deployed
  • A pre-tied, self-sliding knot is then advanced to compress the tear 1

• Suture Configuration: Creates either vertical or horizontal mattress sutures, with vertical being the preferred configuration for optimal healing 1

Technical Specifications

• Depth Penetration: Comes preset with a depth limiter of 22mm (can be adjusted to avoid penetration of superficial structures) 2
• Placement Interval: Typically placed at 5-7mm intervals along the tear 2
• Number Required: Average of 2.8 devices per repair (range 1-5) depending on tear length 1

Clinical Applications

The FasT-Fix is primarily indicated for:

• Tears in the peripheral/vascular "red zone" or "red-white zone" (outer 1/3 to middle 1/3 of meniscus) 3
• Tears with at least a 2mm peripheral rim 1
• Predominantly middle and posterior third meniscal tears 1
• Meniscal ramp lesions (often occurring with ACL injuries) 4

Advantages

• Shorter operating time compared to traditional techniques 3
• Reduced morbidity compared to inside-out techniques 3
• High deployment success rate (98.6%) 5
• No reported cases of articular cartilage damage from the knots 1
• Allows for strong vertical mattress suture configuration 1

Limitations and Potential Pitfalls

• Anatomical Limitations: Cannot effectively be inserted into the anterior meniscus or extreme posterior horn 2

• Technical Challenges:

  • Risk of penetrating superficial structures (iliotibial tract, skin) with the preset depth limiter 2
  • Suture tensioning issues including suture failure during tightening 2
  • Intra-articular deployment of implants 2
  • Premature deployment of implants 2
  • Difficulty in advancing the trigger for deployment of the second implant 2

• Healing Outcomes: Some studies suggest inferior meniscal healing compared to inside-out suture techniques in animal models 5

• Cost: Higher cost compared to traditional techniques 3

Clinical Outcomes

• Success rates of 86-90.2% reported in clinical studies 1, 6
• Significant improvements in functional outcomes (Lysholm scores improved from 43.6-69 preoperatively to 87.5-94 postoperatively) 1, 6
• Low complication rates comparable to classic suture repair techniques 1
• Particularly effective when used in conjunction with ACL reconstruction (91% success rate) 1

The FasT-Fix device represents an effective option for meniscal repair, offering the benefits of an all-inside technique while maintaining the strong suture configuration traditionally achieved with inside-out repairs.