Table 2 The treatment protocols of LP-PRP and HA injections 

Cerza et al., 2012 (Italy) [19]

5.5

1

4

Autologous blood was drawn from patients, processed using a specific protocol to concentrate platelets, and then administered as 5.5 mL of autologous conditioned plasma

20 mg/2 mL

1

4

Commercially available product. Performed by an unblinded physician

Sánchez et al., 2012 (Spain) [18]

8

1

3

Autologous blood was drawn from patients, processed to concentrate platelets, and then injected in a series of 3 weekly sessions

NA

1

3

Commercially available product. Performed by an unblinded physician

Say et al., 2012 (Turkey) [16]

2.5

NA

1

Prepared from the patient’s autologous blood but not mentioned the process

25 mg/2.5 mL

1

3

Commercially available product, and injected under sterile conditions

Vaquerizo et al., 2013 (Spain) [21]

8

2

3

36 mL of blood was drawn from each patient, centrifuged at 580g for 8 min, and the PRGF-Endoret was separated from the red blood cells and leukocytes. The 2 mL PRGF-Endoret fractions were combined into 8 mL, activated with 400 µL calcium chloride, and injected as 8 mL into the joint

NA

NA

1

A single injection of Durolane (hyaluronic acid) was administered, which is a high-molecular-weight molecule synthesized via biofermentation using nonpathogenic Streptococcus bacteria and purified

Montañez-Heredia et al., 2016 (Spain) [17]

NS

2

3

18 mL of blood was collected and processed with double-spin centrifugation. The first spin separated plasma and red blood cells, and the second concentrated the platelets. The PRP was activated with calcium chloride or thrombin, and 3 mL was injected into the knee under sterile conditions

NA

2

3

Hylan G-F 20 (Synvisc), a commercially available hyaluronic acid was used, and injected under sterile conditions

Cole et al., 2017 (USA) [26]

4

1

3

Around 10 mL of blood was collected, centrifuged at 1500 rpm for 5 min to produce 4 mL of PRP. The PRP was processed and injected into the knee within 30 min, eliminating the need for anticoagulants

16 mg/ 2 ml

1

3

Commercially available product (Sanofi-Aventis) was administered

Raeissadat et al., 2017 (Iran) [22]

5

3

2

PRP was processed with the Rooyagen Kit. After drawing 35–40 mL of blood and adding 5 mL of anticoagulant, the blood was centrifuged at 1600 rpm for 15 min to separate the layers. The plasma and buffy coat were then centrifuged at 2800 rpm for 7 min, yielding 4–6 mL of PRP with leukocytes

20 mg

1

3

Commercially available product (Hyalgan, Fidia Farmaceutici S.p.A., Abano Terme, Italy) was administered. Performed by an unblinded physician

Louis et al., 2018 (France) [23]

3

NA

1

30 mL of blood was drawn and mixed with 3 mL of acid-citrate-dextrose. After centrifugation at 1500 rpm for 10 min, the plasma layer containing concentrated platelets was collected for injection

60 mg/ 3 ml

NA

1

Hylan G-F 20 (Synvisc), a commercially available hyaluronic acid was used

Buendía‐López et al., 2019 (Spain) [25]

5

NA

NA

18 mL of blood was collected, centrifuged twice at 1800 rpm and 3500 rpm to concentrate platelets. The PRP was activated with calcium chloride or thrombin, then 3 mL was injected into the knee under sterile conditions

60 mg/ 2 ml

NA

NA

Hylan G-F 20 (Synvisc), a commercially available hyaluronic acid was used

Huang et al., 2019 (China) [24]

2

1

3

8 mL of blood was collected from the cubital vein and centrifuged for 5 min at either 1500 g or 3500 rpm, based on manufacturer recommendations. This process utilized a single centrifugation step, which separated blood components into layers. Erythrocytes settled at the bottom, followed by a buffy coat of white blood cells, and platelets concentrated just above the buffy coat within the plasma

4 ml (500–730 kDa)

1

3

A commercially available hyaluronic acid was used (SK chemical research Co., Ltd., Tokyo, Japan). Performed by an unblinded physician

Lin et al., 2019 (Taiwan) [20]

5

1

3

PRP was prepared using RegenKit-THT, where 10 mL of blood was drawn and centrifuged at 1500 rpm for 8 min. This yielded about 5.0 ± 0.5 mL of PRP, with a platelet concentration of 1.81 ± 0.34 times the baseline. The product was leukocyte poor, as nearly 70% of white blood cells were removed during centrifugation

20 mg/ 2 ml

1

3

A commercially available hyaluronic acid was used. Performed by an unblinded physician

Xu et al., 2021 (China) [15]

4

2

3

A 36-mL blood sample was collected and mixed with 4 mL of acid citrate dextrose, then centrifuged at 160g for 10 min to separate components. Platelet-containing plasma was transferred, centrifuged again at 250g for 15 min, and the resulting leukocyte-poor PRP was collected using a 5-mL syringe

20 mg/ 2 ml

2

3

A commercially available hyaluronic acid was used. Performed by an unblinded physician