Assessing the Tendons With Shear Wave Elastography

Assessing the Efficacy of Ultrasound-Guided Needle Tenotomy/PRP Injection in the Treatment of Tendinopathy With Real Time Shear Wave Elastography

The purpose of this prospective study is to utilize a real-time ultrasound modality known as real-time Shear Wave Elastography (SWE) to first study the viscoelastic properties of tendons, such as the Achilles, patellar, quadriceps, epicondylar, and rotator cuff, to understand the functional differences between normal/asymptomatic vs tendinotic/symptomatic tendon states. The secondary aim will be to assess the degree of tendon healing after percutaneous tenotomy (a minimally invasive technique that can be used to treat tendinosis) and Platelet-Rich Plasma (PRP) targeting mid-substance tendinopathy. Utilizing a quantitative tool to assess healing response to percutaneous tendon fenestration and PRP injection may have significant clinical implications because it will provide insight into the mechanism of tendon healing.

Tendinopathy is a common affliction in athletes, recreational exercisers, the general population and even inactive people. Tendon pathology presenting clinically is most commonly seen in the chronic state related to tendon degeneration manifested as intra-tendinous mucoid degeneration and chondroid metaplasia, which in many cases is accompanied by superimposed small intrasubstance/interstitial tears. Then a vicious cycle of attempted inadequate healing with superimposed acute pathology ensues leading to significant pain and discomfort over time significantly limiting physical activity. The exact pathogenesis of this disease has not been clarified scientifically. The first part of the study aims to establish the difference between asymptomatic and symptomatic tendons by correlating elastography measurements (axial and sagittal mean velocity and relative anisotropic coefficient) with more standard clinically based outcome measures. Shear Wave Elastography (SWE) will be used with a small group of patients affected by moderate-to-severe, chronic (>6 months of symptoms) tendinopathy in comparison to asymptomatic patients. After establishing a range of normal to severe pathologic elastography measurements the researchers will conduct a 12-month clinical trial to determine whether percutaneous needling with PRP injection improves disease-specific clinical outcomes. PRP injection is commonly used in clinical practice to treat chronic tendinopathy. The pathophysiology is believed to be mediated through a variety of growth factors, including platelet-derived growth factor, transforming growth factor, and insulin-like growth factor, that promote a healing response. One of the main advantages is that PRP is autologous and is prepared at the time of treatment (point of care). It has an excellent safety profile with almost no side effects. SWE imaging will then be used to assess degree of tendon healing following tenotomy-PRP injection.

Participants with moderate to severe tendinosis receiving ultrasound-guided percutaneous tenotomy with an injection of Platelet-Rich Plasma (PRP) to treat chronic tendinopathy

Using an aseptic procedure, 7 cubic centimeters (cc) of blood will be collected and processed for the PRP injection. The site to be injected will be prepared with isopropyl alcohol and then sprayed with ethyl chloride to achieve cutaneous anesthesia. Next, with continuous sonographic visualization, the skin and subcutaneous tissues overlying the tendon will be infiltrated with 0.5% bupivacaine and 1% sodium bicarbonate (50 milliequivalents (mEq)/50 mL) via a 25-gauge hypodermic needle. Once adequate anesthesia is achieved, a 20-gauge needle will be used to repeatedly fenestrate the tendinotic portion of the tendon along the long plane. Any calcifications within the substance of the tendon will be mechanically fragmented. When the region of interest has been treated, a PRP injection (5 cc) will be delivered.

Shear wave elastography imaging will be used to assess the degree of tendon healing after percutaneous tenotomy and PRP injection. Markers for healing assessed by SWE will be determined in Part 1 of this study.

Qualitative measures to assess the degree of tendon healing after percutaneous tenotomy and PRP injection will be measured by B mode sonographic imaging.

The VISA-A scale assesses the severity of chronic Achilles tendinopathy. This 8-item, self-administered questionnaire asks about Achilles tendon pain, daily living function, and sporting activity. Total scores can range from 0 to 100, with 0 representing worst pain and function and 100 signifying no pain or limitations to function. Scores below 70 indicate the presence of Achilles tendinopathy.

The VISA-P scale assesses patellar tendinosis. This 8-item, self-administered questionnaire asks about symptoms, pain, function, and sporting activity. Total scores can range from 0 to 100, with 0 representing worst pain and function and 100 signifying no pain or limitations to function.

The FADI is a self-report instrument assessing function related to the foot and ankle. The FADI has 26 items that are scored on a 5-point scale where 0 = unable to do and 4 = no difficulty at all. Total raw scores range from 0 to 104 and scores are converted to percentages, where 100% indicates no dysfunction.

The FADI Sport is a self-report instrument assessing function related to the foot and ankle in athletes. The FADI Sport has 8 items that are scored on a 5-point scale where 0 = unable to do and 4 = no difficulty at all. Total raw scores range from 0 to 32 and scores are converted to percentages, where 100% indicates no dysfunction.

Inclusion Criteria for Asymptomatic Volunteers: Patients presenting at the study location with lower extremity pain without tendon involvement Inclusion Criteria for Symptomatic Volunteers: Patients presenting at the study location with a clinical diagnosis of tenalgia Diagnosis of tendinopathy confirmed by ultrasound Exclusion Criteria: Pregnancy History of tendinopathy or surgery and morphologic abnormalities History of systemic, metabolic, endocrine diseases, or psoriasis History of treatment with corticosteroids, estrogens, long term quinolone antibiotics, and cholesterol drugs