Thermal Microdebridement Does Not Affect the Time Zero Biomechanical Properties of Human Patellar Tendons

Abstract

Background Thermal microdebridement for the treatment of chronic tendinopathy has recently been introduced. The effect of thermal microdebridement on the biomechanical properties of human tendons, however, remains unknown. Hypothesis Thermal microdebridement does not affect the biomechanical properties of human patellar tendons in a cadaveric model at the time of initial treatment. Study Design Controlled laboratory study. Methods The central 15 mm of 12 matched, human (mean age, 71 years; 8 male, 4 female), fresh-frozen patellar tendons was divided into 3 equal 5-mm specimens. The treatment group (n = 12) underwent thermal microdebridement with a radiofrequency probe. A sham treatment group (n = 12) underwent insertion of a deactivated probe. The control group (n = 12) underwent no treatment. After treatment, each specimen was tested to failure in a servo-hydraulic materials testing machine at an elongation rate of 3 mm/s. One-way repeated measures analysis of variance was used to determine differences between groups. Results No significant difference in ultimate stress at failure, elastic modulus, strain energy density, or strain at maximum load was found between the groups. The ultimate stress at failure for the treatment, sham, and control groups was 61.0, 66.7, and 63.0 MPa, respectively (P = .653), and the strain at maximum load was 0.12, 0.11, and 0.09, respectively (P = .279). Conclusions Thermal microdebridement does not affect the biomechanical properties of cadaveric human patellar tendons at the time of initial treatment. Clinical Relevance It may be safe to proceed with aggressive rehabilitation after thermal microdebridement of the patellar tendon. However, the results in this cadaveric model should be interpreted with caution. Additional studies using an in vivo model will be required to completely assess the effects of thermal microdebridement on the biomechanical properties of human patel-lar tendons.