What is the optimal number of anchors for rotator cuff (RC) repair?

From the Guidelines

The optimal number of anchors for rotator cuff repair should be determined by the operating surgeon based on intraoperative assessment of tear characteristics, tissue quality, and the patient's individual anatomy, rather than adhering to a rigid formula. The number of anchors used in rotator cuff repair typically ranges from 1 to 4, depending on the size and configuration of the tear. For small tears (less than 1 cm), a single anchor may be sufficient, while medium tears (1-3 cm) generally require 2 anchors. Large tears (3-5 cm) typically need 3 anchors, and massive tears (greater than 5 cm) may require 4 or more anchors. The goal is to achieve adequate fixation while distributing tension across the repair site. The surgeon should place anchors at the medial edge of the footprint (where the tendon naturally attaches to bone) to restore the anatomical attachment. Double-row repair techniques, which use anchors in both medial and lateral positions, may provide superior biomechanical strength for larger tears by creating a broader contact area between the tendon and bone.

According to the most recent evidence, 1, the management of rotator cuff injuries should be based on evidence, a physician’s expert judgment, and the patient’s circumstances, values, preferences, and rights. The American Academy of Orthopaedic Surgeons recommends that medical care should be based on mutual collaboration with shared decision making between patient and physician/allied healthcare provider.

Some key considerations for determining the optimal number of anchors include:

• The size and configuration of the tear
• The quality of the tissue
• The patient's individual anatomy
• The goal of achieving adequate fixation while distributing tension across the repair site
• The use of double-row repair techniques for larger tears

It is essential to note that the evidence is limited, and higher quality research is needed to improve confidence in specific treatment practices and to better standardize care, as highlighted in 1. However, based on the available evidence, the operating surgeon should use their expert judgment to determine the optimal number of anchors for each individual patient.

From the Research

Optimal Number of Anchors for Rotator Cuff Repair

The optimal number of anchors for rotator cuff (RC) repair is a topic of ongoing debate, with various studies providing insights into the biomechanical and anatomical aspects of RC repair.

• The use of single-row, double-row, and transosseous equivalent fixation techniques has been explored, with double-row repairs showing improved load to failure and minimal gap formation 2.
• A study on arthroscopic RC repair using a triple-loaded suture anchor and a modified Mason-Allen technique (Alex stitch) demonstrated the effectiveness of this approach in restoring the tendon footprint 3.
• The number of anchors used in RC repair should be based on factors such as minimizing cost, avoiding complications, using appropriate technique, and proper restoration of anatomy 4.
• The use of titanium anchors has been shown to be effective in RC repair, with results comparable to traditional trans-bone suturing techniques 5.
• A study on all-suture anchor settling after arthroscopic repair of small and medium RC tears found that anchor settling tended to increase with deeper time-zero depth to anchor, but did not differ significantly among groups with different shoulder bone mineral densities (BMDs) 6.

Factors Influencing Anchor Number and Placement

Several factors influence the optimal number of anchors and their placement in RC repair, including:

• Tissue quality and tear configuration 2
• Bone quality and density 4, 6
• Surgical technique and experience 3, 5
• Cost and potential complications 4

Biomechanical Considerations

Biomechanical studies have shown that:

• Double-row repairs have an improved load to failure and minimal gap formation compared to single-row repairs 2
• Transosseous equivalent repairs have the highest ultimate load and resistance to shear and rotational forces, and the lowest gap formation 2
• Anchor settling can occur after RC repair, but its clinical significance is unclear 6