Suture Materials for Tendon Repair: Absorbable vs. Non-Absorbable
The choice of suture for repairing a tendon is not one-size-fits-all. It depends on several factors, including the type and location of the tendon, the patient's activity level, and the surgeon's preference. Suture materials fall into two primary categories: non-absorbable and absorbable, each with distinct characteristics that influence their use in surgery.
Non-Absorbable Sutures
Non-absorbable sutures are the most traditional and still-preferred choice for many tendon repairs, offering the highest long-term strength. These sutures do not degrade over time and remain in the body, providing permanent support. They are typically made from synthetic polymers.
- Braided Synthetic Polyester (e.g., Ethibond, FiberWire): These materials are known for their exceptional strength and are a long-standing standard for tendon repair, particularly in high-demand areas like the Achilles tendon. The braided construction provides high tensile strength but also creates more surface friction, which can be a double-edged sword. While it offers a secure knot, it can also increase tendon gliding resistance and may induce a stronger foreign body reaction. Newer, high-strength polyblend materials like FiberWire and FiberLoop are often used for their superior strength and resistance to cyclical loading.
- Monofilament Synthetic (e.g., Prolene, Supramid): These sutures are made of a single filament, offering less friction as they pass through tissue. This can be advantageous in areas where smooth gliding is critical, such as in the hand and fingers. They cause less tissue reaction and are less prone to bacterial wicking than braided sutures. However, they can be more challenging to handle and knot.
Absorbable Sutures
Absorbable sutures are designed to lose their tensile strength and be absorbed by the body over time. While historically considered too weak for long-term tendon repair, modern absorbable materials are proving effective in certain scenarios, such as flexor tendon repairs in the hand.
- Polydioxanone (PDS): This is a commonly used monofilament absorbable suture. Studies comparing PDS to non-absorbable sutures for Achilles tendon repair found comparable outcomes regarding rerupture rates, infection, and foreign body reaction. The primary benefit is that the suture is eventually resorbed, eliminating the potential for long-term foreign body irritation and granuloma formation. The initial strength is sufficient to hold the repair during the critical healing phase before it is absorbed.
The Role of Suture Technique in Tendon Repair
The choice of suture material is inseparable from the surgical technique employed. The technique dictates how the suture is placed and anchored within the tendon, which fundamentally impacts the repair's strength and stability.
- Core Suture Techniques: These involve placing strong, load-bearing sutures through the bulk of the tendon to bring the severed ends together. Popular methods include the Modified Kessler, Bunnell, and three-loop pulley techniques. The number of suture strands crossing the repair site is proportional to the repair's strength.
- Peripheral Circumferential Sutures: Often used in addition to core sutures, these fine sutures are placed around the periphery of the tendon ends. Their purpose is to provide a smooth, gliding surface and prevent gapping at the repair site, which is a major cause of adhesions. While they add strength, they must be used judiciously to avoid creating a high-friction surface that could impede tendon gliding.
Suture Selection Factors Beyond Material
Beyond the fundamental properties of absorbable and non-absorbable materials, surgeons must consider other details when choosing the ideal suture.
Suture Size and Bulk
Suture size, measured in gauge (e.g., 3-0, 4-0), is an important consideration. A thicker suture provides more strength but also adds bulk to the repair, which can increase gliding resistance, particularly in confined spaces like the finger tendons. The goal is to use the smallest caliber suture that provides sufficient strength for the specific repair.
Biocompatibility and Complication Risk
All sutures, being foreign bodies, can cause an inflammatory reaction. Non-absorbable braided sutures, in particular, have been associated with granuloma formation, a localized inflammatory reaction that can present as a soft tissue mass. Absorbable sutures are specifically designed to mitigate this risk by being absorbed over time, but their use must be balanced against the need for prolonged mechanical support.
A Comparison of Tendon Repair Sutures
| Feature | Non-Absorbable Braided (e.g., Ethibond) | Non-Absorbable Monofilament (e.g., Prolene) | Absorbable Monofilament (e.g., PDS) |
|---|---|---|---|
| Strength | Very High | High | Moderate (Decreases over time) |
| Tissue Reaction | Moderate-High (risk of granuloma) | Low | Low (Temporary) |
| Friction | High (secure knots, but increased gliding resistance) | Low (smooth gliding) | Low |
| Handling | Good | Fair (more slippery) | Fair-Good |
| Example Uses | Achilles tendon, general tendon repair | Hand and finger tendons | Selected flexor tendon repairs |
The Evolving Science of Tendon Repair
The landscape of tendon repair is continuously evolving. Modern techniques and materials aim to provide a stronger, more stable repair while minimizing long-term complications. High-strength sutures made of advanced materials, combined with specific suture patterns, allow for earlier mobilization and improved functional outcomes. Surgeons weigh the need for static, long-term strength provided by non-absorbable sutures against the reduced foreign body reaction offered by modern absorbable options. As research continues, the decision of which suture is used for tendon repair will become even more nuanced and patient-specific.
For more detailed information on specific suture materials and their clinical performance, review medical literature such as the article on absorbable vs. non-absorbable sutures for Achilles tendon repair from the National Institutes of Health Absorbable vs Nonabsorbable Sutures for Achilles Tendon Repair.
