Background: Platelet-rich plasma (PRP) contains various growth factors and appears to have a potential to promote tendon healing, but evidence is lacking regarding its effect on human tenocytes from rotator cuff tendons with degenerative tears. Hypothesis: Platelet-rich plasma stimulates cell proliferation and enhances matrix gene expression and synthesis in tenocytes isolated from human rotator cuff tendons with degenerative tears. Study Design: Controlled laboratory study. Methods: Tenocytes were enzymatically isolated and cultured. To evaluate cell proliferation, tenocytes were cultured with 10% (vol/vol) platelet-poor plasma (PPP), PRP activated with calcium, and PRP activated with calcium and thrombin at platelet concentrations of 100, 200, 400, 800, 1000, 2000, 4000, 8000, and 16,000 × 10 ³ /µL for 14 days. Cell number was measured at days 7 and 14. To investigate matrix gene expression and synthesis, cells were cultured with a PPP or PRP gel (10% vol/vol) at a platelet concentration of 1000 × 10 ³ /µL for 14 days. Quantitative real-time reverse transcriptase polymerase chain reaction was performed to determine the expressions of type I and III collagen, decorin, tenascin-C, and scleraxis, and measurements of total collagen and glycosaminoglycan (GAG) synthesis were conducted at days 7 and 14. Results: Platelet-rich plasma significantly increased cell proliferation at days 7 and 14 in a dose-dependent manner, and the addition of thrombin moved up the plateau of proliferation. Platelet-rich plasma significantly induced the gene expression of type I collagen at day 7 but not at day 14, while it significantly promoted that of type III both at days 7 and 14. The ratio of type III/I collagens did not change at days 7 and 14. The expressions of decorin and scleraxis significantly increased at day 14, whereas that of tenascin-C significantly increased at days 7 and 14. Platelet-rich plasma significantly increased total collagen synthesis at days 7 and 14 and GAG synthesis at day 14. Conclusion: Platelet-rich plasma promoted cell proliferation and enhanced gene expression and the synthesis of tendon matrix in tenocytes from human rotator cuff tendons with degenerative tears. Clinical Relevance: These findings suggest that PRP might be used as a useful biological tool for regenerative healing of rotator cuff tears by enhancing the proliferation and matrix synthesis of tenocytes from tendons with degenerative tears.

Background: Platelet-rich plasma (PRP) is expected to have a biological augmentation potential in the healing of various diseases and injuries, including rotator cuff tears. However, few evaluations have been performed specifically for large to massive tears. Purpose: To assess the efficacy of PRP augmentation in patients undergoing arthroscopic repair for large to massive rotator cuff tears. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 48 patients scheduled for arthroscopic repair of large to massive rotator cuff tears were randomly assigned to receive either PRP-augmented (PRP group) or conventional treatment (conventional group). In the PRP group, 3 PRP gels (3 × 3 mL) were applied to each patient between the torn end and the greater tuberosity. The primary outcome measure was the retear rate assessed by magnetic resonance imaging (MRI) or computed tomographic arthrography (CTA) at a minimum of 9 months after surgery. Secondary outcome measures included pain, range of motion, muscle strength, overall satisfaction, functional scores, and the change in cross-sectional area (CSA) of the supraspinatus. Results: The retear rate of the PRP group (20.0%) was significantly lower than that of the conventional group (55.6%) ( P = .023). Clinical outcomes showed no statistical difference between the 2 groups (all P > .05) except for the overall function ( P = .043). The change in 1-year postoperative and immediately postoperative CSA was significantly different between the 2 groups: –15.54 ± 94.34 mm ² in the PRP group versus −85.62 ± 103.57 mm ² in the conventional group ( P = .047). Conclusion: The application of PRP for large to massive rotator cuff repairs significantly improved structural outcomes, as evidenced by a decreased retear rate and increased CSA of the supraspinatus compared with repairs without PRP augmentation. While there was no significant difference in clinical outcomes except the overall shoulder function after 1-year follow-up, better structural outcomes in the PRP group might suggest improved clinical outcomes at longer term follow-up.

Background: Platelet-rich plasma (PRP) has been recently used to enhance and accelerate the healing of musculoskeletal injuries and diseases, but evidence is still lacking, especially on its effects after rotator cuff repair. Hypothesis: Platelet-rich plasma accelerates recovery after arthroscopic rotator cuff repair in pain relief, functional outcome, overall satisfaction, and enhanced structural integrity of repaired tendon. Study Design: Cohort study; Level of evidence, 2. Methods: Forty-two patients with full-thickness rotator cuff tears were included. Patients were informed about the use of PRP before surgery and decided themselves whether to have PRP placed at the time of surgery. Nineteen patients underwent arthroscopic rotator cuff repair with PRP and 23 without. Platelet-rich plasma was prepared via plateletpheresis and applied in the form of a gel threaded to a suture and placed at the interface between tendon and bone. Outcomes were assessed preoperatively and at 3, 6, 12, and finally at a minimum of 16 months after surgery (at an average of 19.7 ± 1.9 months) with respect to pain, range of motion, strength, and overall satisfaction, and with respect to functional scores as determined using the following scoring systems: the American Shoulder and Elbow Surgeon (ASES) system, the Constant system, the University of California at Los Angeles (UCLA) system, the Disabilities of the Arm, Shoulder and Hand (DASH) system, the Simple Shoulder Test (SST) system, and the Shoulder Pain and Disability Index (SPADI) system. At a minimum of 9 months after surgery, repaired tendon structural integrities were assessed by magnetic resonance imaging. Results: Platelet-rich plasma gel application to arthroscopic rotator cuff repairs did not accelerate recovery with respect to pain, range of motion, strength, functional scores, or overall satisfaction as compared with conventional repair at any time point. Whereas magnetic resonance imaging demonstrated a retear rate of 26.7% in the PRP group and 41.2% in the conventional group, there was no statistical significance between the groups (P = .388). Conclusion: The results suggest that PRP application during arthroscopic rotator cuff repair did not clearly demonstrate accelerated recovery clinically or anatomically except for an improvement in internal rotation. Nevertheless, as the study may have been underpowered to detect clinically important differences in the structural integrity, additional investigations, including the optimization of PRP preparation and a larger randomized study powered for healing rate, are necessary to further determine the effect of PRP.

Background: Two main questions about the use of platelet-rich plasma (PRP) for regeneration purposes are its effect on the speed of healing and the quality of healing. Despite recent numerous studies, evidence is still lacking in this area, especially in a representative patient population with medium to large rotator cuff tears. Purpose: To assess the efficacy of PRP augmentation on the speed and quality of healing in patients undergoing arthroscopic repair for medium to large rotator cuff tears. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 74 patients scheduled for arthroscopic repair of medium to large rotator cuff tears were randomly assigned to undergo either PRP-augmented repair (PRP group) or conventional repair (conventional group). In the PRP group, 3 PRP gels (3 × 3 mL) were applied to each patient between the torn end and the greater tuberosity. The primary outcome was the Constant score at 3 months after surgery. Secondary outcome measures included the visual analog scale (VAS) for pain, range of motion (ROM), muscle strength, overall satisfaction and function, functional scores, retear rate, and change in the cross-sectional area (CSA) of the supraspinatus muscle. Results: There was no difference between the 2 groups in the Constant score at 3 months ( P > .05). The 2 groups had similar results on the VAS for pain, ROM, muscle strength, overall satisfaction and function, and other functional scores (all P > .05) except for the VAS for worst pain ( P = .043). The retear rate of the PRP group (3.0%) was significantly lower than that of the conventional group (20.0%) ( P = .032). The change in 1-year postoperative and immediately postoperative CSAs was significantly different between the 2 groups: –36.76 ± 45.31 mm ² in the PRP group versus −67.47 ± 47.26 mm ² in the conventional group ( P = .014). Conclusion: Compared with repairs without PRP augmentation, the current PRP preparation and application methods for medium to large rotator cuff repairs significantly improved the quality, as evidenced by a decreased retear rate and increased CSA of the supraspinatus, but not the speed of healing. However, further studies may be needed to investigate the effects of PRP on the speed of healing without risking the quality.