Biomechanical evaluation of arthroscopic rotator cuff repairs over time.

Abstract

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