Table 1 Synopsis of all the clinical studies on PRP application in ankle cartilage pathology

Mei-Dan et al. AJSM 2012 [17]

I – Randomized trial

Osteochondral lesions of the talus

Leukocyte-poor PRP

3 injections of 2 ml PRP, at two-weeks interval

7 months

Statistically significant better clinical outcome for PRP group

Single centrifugation

Platelet count: 2-3x basal value

Activation: Ca-chloride

Angthong et al. J Foot Ankle Surg 2013 [18]

IV – Case series

Ankle OA

Low platelet concentrate, leukocyte poor PRP

One injection of 3 ml PRP

5

16 months

Significant clinical improvement without any change in OA grade

Single centrifugation

Activation: No

Guney et al. KSTTA 2013 [19]

II – Randomized trial

Osteochondral lesion of the talus

Platelet count: 5.4x basal value

One PRP injection (6–24 hours after performing microfractures)

16 months

Combined treatment with PRP determined significantly better outcomes in terms of functional scores with respect to bone marrow stimulation alone.

Leukocyte: n.a.

10% NAHCO3 addition before PRP injection

Giannini et al. Clin Orthop Rel Res 2009 [20]

IV – case series

Osteochondral lesion of the talus

Double centrifugation, leukocyte rich PRF

PRP added intra-operatively to the biomaterial during the osteochondral lesion repair

48

24 months

Significant improvement in the AOFAS score of the patietns treated at final FU. 75% of the patients were able to resume sports activity. Cartilage with hyaline appearance in the 2 second look biopsies performed.

Platelet count 5x basal value

Giannini et al. Injury 2010 [21]

III – retrospective comparative trial

Osteochondral lesion of the talus

PRP added intra-operatively to the biomaterial during the osteochondral lesion repair

36 months

All the 3 groups had similar patterns of clinical improvement. The one step technique was cheaper.

Battaglia et al. Eur J Radiol 2011 [22]

IV – case series

Osteochondral lesion of the talus

PRP added intra-operatively to the biomaterial during the osteochondral lesion repair

24 months

Regenerated tissue with a T2 relaxation time value comparable to hyalinecartilage was found in all the treated cases, covering a mean of 78% of the repaired lesion area.

Giannini et al. Am J Sports med 2013 [23]

IV – case series

Osteochondral lesion of the talus

PRP added intra-operatively to the biomaterial during the osteochondral lesion repair

48 months

A significant relationship between the AOFAS score at 48 months’ follow-up and the percentage of regenerated cartilage with hyaline features (T2 value of 35–45 ms). Patients with hyaline-like regenerated cartilage in more than 80% of the treated area had a more predictable and stable result.