Authors’ Disclosure Statement: The authors report that this study was supported by a grant from Arthrex.
Dr. Komatsu is a Research Assistant Professor, Department of Orthopaedics; and Mr. Gurevich is a Fellow, Medical Scientist Training Program, Stony Brook University, Stony Brook, New York. Dr. King is an Orthopedic Surgeon, Parkview Orthopedics, Pueblo, Colorado. Dr. Paci is Director of Orthopedic Surgery and Sports Medicine for Suffolk County, The Orlin & Cohen Orthopedic Group, Northwell Health, Long Island, New York. Mr. Kahn is a Medical Student, School of Medicine, St. George’s University, Grenada, West Indies.
Address correspondence to: James M. Paci, MD, The Orlin & Cohen Orthopedic Group, 45 Crossways Park Drive, Woodbury, NY 11797 (tel, 631-267-5100; email, james_paci@yahoo.com).
David E. Komatsu, PhD Lucas King, MD Mikhail Gurevich, BS Benjamin Kahn, BA James M. Paci, MD . The In Vivo Impact of Leukocyte Injections on Normal Rat Achilles Tendons: Potential Detriment to Tendon Morphology, Cellularity, and Vascularity. Am J Orthop.
October 1, 2018
TAKE-HOME POINTS
Injection of leukocytes into healthy rat Achilles tendons increases inflammation.
Injection of leukocytes into healthy rat Achilles tendons does not affect vascularity.
Leukocyte-rich PRP preparations may be contraindicated in settings of acute tendonitis.
Leukocyte-rich PRP preparations may be useful for chronic tendinosis.
The concentration and composition of white blood cells within PRP preparations is variable and needs to be better understood in order to optimize clinical utility of PRP injections.
References
ABSTRACT
In this study, we determine the in vivo effects of injecting sub-populations of leukocytes into normal rat Achilles tendons via a controlled laboratory study. Allogenic monocytes, granulocytes, or plasma were injected into 24 healthy rat Achilles tendons. Treated and contralateral un-treated control tendons then assessed for cellularity, histologic morphology, and vascularity after 7 and 14 days. Significant increases of 221% and 249% in cellularity (P = 0.014) were seen on day 14 within Achilles tendons injected with granulocytes as compared to plasma and monocytes, respectively. Also, significant improvement in morphology (P = 0.029) between days 7 and 14 was seen for the granulocyte injected Achilles tendons. Significant increases in cellularity after an injection of granulocytes, compared to monocytes and plasma, corresponds to a significant increase in inflammation within the tissue, suggesting that leukocyte-rich platelet-rich plasma (PRP) preparations are proinflammatory and potentially catabolic when injected into tendon tissue. The concentration and composition of white blood cells within PRP preparations is variable and needs to be better understood in order to optimize clinical utility of PRP injections.
Continue to: Tendinopathies are debilitating conditions...