PLATELET RICH PLASMA (PRP) INJECTION IN PARTIAL-THICKNESS TEARS

The included PRP studies reveal heterogeneity in outcome reporting, variability in conclusions (contradictory in some studies), and non-superiority when compared to established treatments such as CS. As such, the strength of recommendation has been downgraded to limited.
Several high- and moderate- quality studies investigated the use of PRP for cuff tendinopathy or partial-thickness tear. Beginning with the high-quality studies, El-Sherif et al (2023) demonstrated better pain control, SPADI scores, and range of motion (ROM) when compared to saline. Sari et al (2020) found improved ASES and WORC scores with PRP versus lidocaine injection. Cai et al (2019) demonstrated better VAS pain levels and outcome scores (ASES, CM) when comparing PRP to saline and PRP + HA to saline at one year follow-up. In contradistinction, Schwitzguebel and coauthors (2019), found no benefit of PRP over saline with regards to outcome scores (SANE, CM). Additionally, Kesikburun et al (high quality, 2013) found no benefit of PRP over saline using PROs (WORC, SPADI), VAS pain level, and ROM. Akan et al (moderate quality, 2019) compared physical therapy (PT) to PRP, and found PRP to be superior when evaluating CM, QuickDash, and SDI as end outcomes. Similarly, Serya et al (moderate quality, 2021) found PRP to be superior to PT when using DASH outcome and with respect to ROM. Nejati et al (moderate quality, 2017) found conflicting results when comparing PRP versus PT depending on the outcome (WORC versus DASH) and motion/strength parameter. There was a trend towards exercises providing better ROM when compared to PRP. Rha et al (moderate quality, 2013) found PRP to be superior to “dry needling” using SPADI as PRO and ROM.

There are multiple high and moderate level studies comparing PRP to CS with regards to pain level, PROs, and ROM. Some studies such as Vaquerizo et (2023) and Prasad et al (2024) found PRP injections to be better with respect to CM, OSS, QuickDash, and pain level. Others such as Dadgostar et al (2021), Barreto et al (2019), and Oudelaar et al (2021) did not reach the same conclusions (found equivalency). Regarding adverse events, neither treatment modality demonstrated superiority. The study by Halm-Pozniak (2023) cannot be included as it compares PRP with a recombinant scaffold versus CS.

There are two studies comparing PRP to HA, one of high (Cai, 2019) and the other of low (Huang, 2022) quality. Cai found conflicting results when comparing PRP to HA PROs (ASES, CM, and VAS scores) with a trend favoring PRP. Huang found no difference with regards to SPADI and ROM when comparing PRP and HA.

There is one moderate quality study (Markazi, 2022) that compared PRP versus keterolac. There was a trend towards better PROs, ROM, and pain relief with PRP.

There are two high quality (Abd Karim, 2023; Sari 2020) and one moderate quality (Sabaah, 2020) studies comparing PRP versus prolotherapy. Abd Karim et al did not find benefit of PRP compared to prolotherapy with regard to PROs (ASES, SPADI) pain relief, and ROM. Sari found better PRO (WORC) at 6 months and similar pain scores with PRP compared to prolotherapy. Sabaah found better pain control at 6 months with prolotherapy.

Risks and Harms of Implementing this Recommendation
There are no known risks to PRP injections that are specific to shoulders or the rotator cuff.

Future Research
Further research may be conducted to further define the role of PRP injections in rotator cuff pathology. Future studies should standardize the technique and type of PRP formulation utilized and measure the concentrations of key components.