28 patients were injected with 2 mL of autologous blood under ECRB; 19/28 patients received 1 injection; 7/28 patients received 2 injections; 2/28 patients received 3 injections
0–10 patient ratings of pain; patient rating according to Nirschl staging (0–7)
79% of all patients with complete resolution of pain at average of 9.5 months of follow-up; reduction in pain score from mean of 7.8 to 2.3 at last follow-up; reduction in Nirschl staging from mean of 6.5 to 2.0 at last follow-up
60% improvement in VAS with PRP versus 16% improvement in controls at eight weeks (); PRP group had 93% reduction in pain at final follow-up compared to baseline ()
12 treated with injection of collagen-producing tenocyte-like cells derived from autologous skin fibroblasts
PRTEE
Significant improvement in PRTEE scores at 6 weeks, 3 months, and 6 months compared to baseline; significant improvement in tendon structure noted on ultrasound
51 treated with PRP; 49 treated with corticosteroid
Successful outcome: >25% reduction in VAS or DASH score without reintervention
73% successful outcome in PRP group versus 49% successful outcome in corticosteroid group based on VAS () at 1 year; 73% successful outcome in PRP group versus 51% successful outcome in corticosteroid group based on DASH score () at 1 year
51 treated with PRP; 49 treated with corticosteroid
Successful outcome: >25% reduction in VAS or DASH score without reintervention
77% successful outcome in PRP group versus 43% successful outcome in corticosteroid group based on VAS at 2 years (); 73% successful outcome in PRP group versus 39% successful outcome in corticosteroid group based on DASH score at 2 years ()
9 treated with ABI and lidocaine; 9 treated with steroid and lidocaine; 10 treated with saline and lidocaine
DASH scores: PRFE pain and function scores; VAS score
No significance in DASH scores, PRFE pain scores, and VAS scores between the three groups at 2 months or 6 months of follow-up; PRFE function score significantly better for saline compared to PRP group at 6 months
PRP group had significantly greater improvement in VAS for pain at 6 weeks compared to ABI group (); no significant difference in VAS for pain at 3 months and 6 months; no significant differences in Liverpool elbow score at all time points
16 treated with injection of autologous tenocytes derived from patellar tendon cells
VAS, Quick-DASH, grip strength, and grade of tendinopathy at common extensor origin on MRI
Significant improvement at 1, 3, 6, and 12 months in mean VAS, Quick-DASH scores, and grip strength; significant improvement in grade of tendinopathy on MRI at 12 months
Successful outcome: improvement of >25% in VAS with resisted wrist extension; patient-reported elbow tenderness
No significant difference in successful outcomes or percentage reporting elbow tenderness at 12 weeks; success rate of 83.9% in PRP group versus 68.3% in control group at 24 weeks (); significant elbow tenderness reported in 29.1% of PRP group versus 54.0% of control group at 24 weeks ()
VAS, pressure pain threshold, modified Mayo clinic performance index
Significant improvement in both groups in all pain variables compared to baseline at 4 weeks, 8 weeks, 6 months, and 12 months; no significant differences between ABI and PRP groups at any follow-up point
ABI = autologous blood injection; PRP = platelet rich plasma; DASH = Disabilities of the Arm, Shoulder, and Hand; PRFE = Patient-Rated Forearm Evaluation; PRTEE = Patient-Rated Tennis Elbow Evaluation; RCT = randomized controlled trial; VAS = visual analog scale. Note: trials of Peerbooms et al. [42] and Gosens et al. [43] include the same patient cohort with different time points of follow-up.