Background: Greater Trochanteric Pain Syndrome (GTPS) is a frequent clinical condition characterized by acute or chronic pain in the lateral region of the hip. This condition is primarily due to gluteus minimus and medius tendinopathy. Swine-derived type I collagen has shown a positive effect on tenocytes through in vitro studies and on tendinopathies in clinical studies. This pilot study aims to evaluate the clinical effects of swine-derived type I collagen injections on pain, hip function, and strength in GTPS patients. Methods: The study group was treated with three ultrasound-guided swine-derived type I collagen injections once a week for three consecutive weeks. The primary endpoint was pain reduction of at least 3 points on the Numeric Rating Scale (NRS) at ten weeks. Secondary endpoints were NRS average reduction at rest and palpation, modified Harris Hip Score (mHHS), abductor strength, and magnetic resonance imaging (MRI) improvement at six months. Results: 52 patients were screened, 47 enrolled, and 43 completed the study. The primary endpoint was reached by 60.5% of the patients. All secondary endpoints were also reached with statistical significance. Neither early nor late adverse effects were found. Conclusions: In this pilot study, ultrasound-guided peritrochanteric swine-derived type I collagen injections are safe and effective for most patients with GTPS included in the study. Further and more extensive confirmatory investigation studies with a longer follow-up are needed to confirm this pilot study’s results and the clinical benefit’s persistence.

Background: Greater Trochanteric Pain Syndrome (GTPS) is a frequent clinical condition characterized by acute or chronic pain in the lateral region of the hip. This condition is primarily due to degenerative gluteus minimus and medius muscle tendinopathy. In a previous ex vivo study, proliferation and migration of human tenocytes and synthesis, maturation, and secretion of Collagen I (COL-I) were improved when human gluteal tenocytes were exposed to a swine-derived type I collagen available on the market (MD-Tissue—GUNA S.p.a. Milan, Italy). The study's purpose is to evaluate the effects of injecting an MD-tissue medical device on GTPS pain, hip function, and strength. Methods: The study group was treated with ultrasound-guided injections of swine-derived collagen once a week for three consecutive weeks. Primary endpoint was pain reduction of at least 3 points on the Numeric Rating Scale (NRS) for pain at ten weeks. Secondary endpoints were: NRS average reduction at rest and palpation, modified Harris Hip Score (mHHS), abductor strength, and magnetic resonance imaging (MRI) improvement at six months. Results: Fifty-two patients were screened, 47 enrolled, 43 completed the study, and 42 were available for the final follow-up. The primary endpoint was reached in more than 60% of the patients. The secondary endpoint, increased in all the timelines with statistical significance. Neither early nor late adverse effects were found. Conclusions: Ultrasound-guided peritrochanteric injections of MD-Tissue are a safe and effective treatment for the majority of the Patients affected by Greater Trochanteric Pain Syndrome.