[Comparative study on effectiveness of injecting platelet-rich plasma with different concentrations of leukocytes under ultrasound in treatment of supraspinatus tendon injury].

Objective: To compare effectiveness of injecting platelet-rich plasma (PRP) with different concentrations of leukocytes under ultrasound in treatment of supraspinatus tendon injury.

Methods: A clinical data of 30 patients with supraspinatus tendon injury, who met the selection criteria and were admitted between December 2022 and December 2023, was retrospectively analyzed. Thirty patients were treated with 4 injections of leukocyte-poor PRP (LP-PRP, n=10), leukocyte-rich PRP (LR-PRP, n=11), and triamcinolone ( n=9), with an interval of 7-10 days between each injection. There was no significant difference between groups ( P>0.05) in the age, gender, disease duration, affected shoulder side, Ellman classification, preoperative visual analogue scale (VAS) score, Constant score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and American Shoulder and Elbow Surgeons (ASES) score. At 1, 3, and 6 months after injection, the shoulder pain and function were evaluated by using the VAS score, Constant score, DASH score, and ASES score. MRI was conducted to observe supraspinatus tendon healing.

Results: No severe adverse reactions was observed in all groups. All patients were followed up 6-7 months, with an average of 6.5 months. After injection, the ASES score and Constant score gradually increased in the LR-PRP group and LP-PRP group, while the VAS score and DASH score decreased, with significant differences compared to before injection ( P<0.05). Except for no significant difference between 3 and 6 months after injection in LR-PRP group ( P>0.05), the above scores showed significant differences between different time points ( P<0.05). At 1 month after injection, the Constant score in triamcinolone group significantly increased compared to before injection, while the VAS score significantly decreased ( P<0.05). There was no significant difference in all scores between other time points in the triamcinolone group ( P>0.05). Except for 1 month after injection, there was no significant difference in Constant score and VAS score between groups ( P>0.05). At all other time points, the LR-PRP group and LP-PRP group had better scores than the triamcinolone group ( P<0.05). There was no significant difference between the LR-PRP group and the LP-PRP group ( P>0.05). MRI showed that only 4 patients in the LP-PRP group had signs of repair at the supraspinatus tendon injury site at 6 months after injection, while no significant tendon repair sign was observed in the other patients.

Conclusion: Compared with triamcinolone treatment, multiple injections of LP-PRP and LR-PRP under ultrasound can promote the recovery of shoulder joint function and significantly relieve pain in patients with supraspinatus tendon injury, and imaging improvement can be seen after LP-PRP treatment.