Biomechanical evaluation of arthroscopic rotator cuff repairs over time.

PURPOSE: The aim of this study was to assess the contact pressure, force, and area over time for 4 common arthroscopic rotator cuff repair techniques.

METHODS

The transosseous-equivalent, single-row, triangle double-row, and suture-chain transosseous repair techniques were used to repair a full-thickness tear of the supraspinatus in 16 cadaveric shoulders. Continuous data points were collected immediately after repair and for 160 minutes at set time intervals by use of a custom thin film pressure sensor.

RESULTS

Each of the 4 rotator cuff repair techniques showed decreased contact force, pressure, and area 160 minutes after the repair was performed. The transosseous-equivalent construct had the highest contact pressure and force initially and at all time points up to 160 minutes. Although the 3 double-row constructs had greater pressure and force at all time points compared with the single-row repair, only the transosseous-equivalent group showed a statistically greater pressure and force when compared with single-row repair (P < .05).

CONCLUSIONS

Contact pressure, force, and pressurized footprint area decrease 160 minutes after repair regardless of repair technique. The transosseous-equivalent group had the highest contact pressure and force at all time points.

CLINICAL RELEVANCE: The decrease in contact pressure and force after rotator cuff repair may have important implications in evaluating tendon-to-bone healing and determining the optimal rehabilitation protocol.