Comparing PRP Injections With ESWT for Athletes With Chronic Patellar Tendinopathy.

Dr Jay Smith from Mayo Clinic, Publishes New Platelet Rich Plasma Article: Comparing PRP Injections with Extracorporeal shock-wave therapy for Athletes with Chronic Patellar Tendinopathy

Upcoming speaker at The Orthobiologic Institute (TOBI) 5th Annual PRP & Regenerative Medicine Symposium with Cadaver Lab, Dr Jay Smith, recently published a paper in the Clinical Journal of Sports Medicine comparing the effectiveness of Platelet Rich Plasma (PRP) versus Extracorporeal Shock-wave Therapy (ESWT) for athletes with chronic patellar tendinopathy, “jumper’s knee”.
The randomized controlled study examined 46 individuals with ultrasound diagnosed unilateral Jumper’s knee for greater than 6 months. 

Twenty-three patients underwent 2 PRP injections directly into the affected patellar tendon, separated by 1 week. While, twenty- three patients underwent 3 treatments of ESWT separated by 48-72 hours. One week post-procedure, each treatment group initiated a stretching and strengthening program for 2 weeks duration, and gradually resumed normal daily and athletic activity by 4 weeks post-treatment.

The results of the 12-month follow up period showed significant improvements from baseline in both the PRP and ESWT groups, assessed via the Victorian Institute of Sports Assessment-Patella (VISA-P) questionnaire and Visual Analogue Scale during 5 single leg squats. The PRP group illustrated significantly greater improvements in VISA-P scores at 6 and 12 months follow-up, while also revealing similar improvements in VAS scores during single leg squatting. Furthermore, at the end of the 12 months follow-up period, 91% of PRP patients rated their “response to treatment” as good or excellent, in comparison to only 60.8% in the ESWT group. 

The study illustrates the positive effects of both extracorporeal shockwave therapy and intra-tendon PRP injection on chronic patellar tendinopathy. However, the results of the study show greater 6 months improvements and better overall functional outcomes and patient satisfaction at 12 months with PRP treatment. Although additional studies are needed to confirm these findings and further investigate PRP efficacy, this study provides preliminary data illustrating the potential therapeutic effects of PRP in the treatment of chronic “jumper’s knee”.


Dr Jay Smith is providing the Musculoskeletal Ultrasound Lecture & Live Model Demonstration: Sonoanatomy for Ultrasound Guided Procedures for The Orthobiologic Institute (TOBI) Cadaver Lab: Ultrasound-guided Injections and Bone Marrow Aspirate, June 7, 2014 in Las Vegas. Join Dr. Smith for over 20 lectures with field leaders, the latest research and world-class networking at The Orthobiologic Institute (TOBI) 5th Annual PRP & Regenerative Medicine Symposium with Cadaver Lab, June 6-7, 2014 in Las Vegas.

Clin J Sport Med. 2014 Jan;24(1):88-9. doi: 10.1097/JSM.0000000000000063.

Comparing PRP Injections With ESWT for Athletes With Chronic Patellar Tendinopathy.

Author information

  • Department of Physical Medicine and Rehabilitation Sports Medicine Center, Mayo Clinic Rochester, Minnesota.



To compare the effectiveness of injections of platelet-rich plasma (PRP) compared with focused extracorporeal shock-wave therapy (ESWT) among athletes with chronic patellar tendinopathy (jumper’s knee).


Randomized controlled single-center trial, with 12 months of follow-up.


Tertiary-level care in Rome, Italy. Patients were recruited from January 2009 to May 2011.


Patients who received a diagnosis of jumper’s knee from a participating physician were recruited into the study (n = 46). Inclusion criteria were chronic (≥6 months), unilateral, proximal patellar tendinopathy in a recreational or elite athlete confirmed by ultrasound (US); prior failed nonoperative management that concluded ≥12 weeks prior to study entry; and ages 18 to 50 years. Exclusion criteria were coexisting knee lesions, systemic disorders, knee surgery or corticosteroid injection in the previous 3 months, and contraindications to PRP treatment.


Patients in the PRP group (n = 23) received 2 US-guided injections separated by 1 week and directed at the affected tendon portion. Each injection consisted of 2 mL of nonactivated, autologous PRP extracted from a single centrifugation of 10-mL blood and administered by a trained physician via a 22-guage needle. Patients in the focused ESWT group (n = 23) received 3 treatments (2400 impulses at 0.17-0.25 mJ/mm per session) separated by 48 to 72 hours. Treatments were guided by inline US and administered by 1 experienced operator. No local anesthesia was used in either group. One week later, both groups began a conventional stretching and strengthening program for 2 weeks. At 4 weeks, patients gradually resumed normal activities and sports, as tolerated.


At 2, 6, and 12 months after treatment, patients were assessed by a single investigator, blinded to group assignment. The main measure was the Italian version of the Victorian Institute of Sports Assessment-Patella (VISA-P) questionnaire, which evaluates severity of symptoms, function, and ability to participate in sport. A 10-cm visual analog scale (VAS) was used to assess pain while doing 5 single-leg squats. Patients also assessed their response to treatment on the Blazina scale (excellent to poor). No patients were lost to follow-up


: During the 12-month follow-up period, VISA-P scores for both groups improved significantly from baseline (55.3 for PRP, 56.1 for ESWT), although the PRP group had greater improvement at 6 months (86.7 vs 73.7; P = 0.014) and 12 months (91.3 vs 77.6; P = 0.026). Pain scores during 5 single-leg squats demonstrated similar findings. At 12 months a greater proportion of patients in the PRP group rated their response to treatment as good or excellent (PRP, 91.3% vs ESWT, 60.8%; P = 0.035), although at earlier follow-ups the groups did not differ. Both the injections and ESWT caused transient discomfort. No patient had surgery during follow-up.


Athletes with chronic patellar tendinopathy responded positively to both PRP injection and ESWT. However, the PRP-treated patients demonstrated significantly greater improvements in VISA-P and pain scores by 6 months and significantly better functional outcomes and satisfaction based on a modified Blazina scale, at 12 months.




[PubMed – in process]