A Pilot Study Correlating Novel Ultrasound Elastography Techniques to Standard Clinical Outcomes in the Treatment of Achilles Tendinopathy With Platelet-Rich Plasma Therapy

The main goal for this pilot level study is to correlate ultrasound elastography technique with more standard clinically based outcome measures within the setting of a small sample sized group of patients affected by moderate-to- severe, chronic (> 6 months) midsubstance Achilles tendinopathy (AT). Investigators will conduct a 24-week, 2-arm randomized controlled pilot study to determine whether novel elastography techniques (AE) and shear wave imaging (SWI), a new quantitative method of ultrasound (US) imaging, correlate with valid clinical outcome measures (VISA-A and conventional US). Methods will be based on recently published clinical trials of autologous blood injections for treating AT and will incorporate novel US outcome measures of Achilles tendon appearance and stiffness, i.e. elasticity. The results of this multi-disciplinary pilot study will be used to help plan a separate larger scaled study to evaluate the effects of platelet-rich plasma (PRP) therapy for Achilles tendinopathy in which elastography will be included as a potential outcome measure and also correlated with standard clinical outcome surveys.

Pain and function will be evaluated by self-report using a validated clinical outcome questionnaire (VISA-A). Disease modification will be assessed by novel US-based AE and SWI methods for stiffness changes (biomechanical) and correlated with morphologic changes using conventional US. A larger study that will evaluate the effects of PRP in healing AT, while correlating with elastography assessment, will include a sham injection arm.

Intervention Subjects assigned to the PRP group will then receive the PRP injection under ultrasound guidance. The injection will take about 15 minutes.

Each subject will undergo a palpatory and ultrasound Achilles tendon exam. Tender areas associated with the Achilles tendon will be identified. Physical exam will be followed by Achilles tendon ultrasound which will serve as visual guidance for injection.

At the injection session, the research nurse will perform a single standard antecubital blood draw (35 mL). The PRP will be obtained from this sample using a two-stage spinning technique: the 1st separates red blood cells from platelets, and the 2nd concentrates the platelets to yield approximately 4 mL of concentrated autologous platelet. This layer of platelet rich plasma will be placed in the syringe by the centrifuge machine.