Is low leukocyte (white blood cell) platelet-rich plasma (PRP) more effective than high leukocyte PRP for treating muscle spasms?

Low Leukocyte PRP is Preferred Over High Leukocyte PRP for Muscle Spasms

Based on current evidence, low leukocyte PRP is likely more beneficial than high leukocyte PRP for treating muscle spasms, as the inflammatory effects of leukocytes may counteract the healing properties needed for muscle recovery.

Understanding PRP Classifications and Leukocyte Content

The International Society on Thrombosis and Haemostasis (ISTH) has established a classification system for PRP preparations that specifically distinguishes between preparations based on leukocyte content 1:

• PRP: Low leukocyte content (<1% of total cells)
• L-PRP: High leukocyte content (≥1% of total cells)

This distinction is clinically relevant because leukocytes influence the biological activity of PRP in tissue healing.

Mechanism of Action and Rationale

When considering muscle spasms specifically:

1. Low leukocyte PRP (PRP):

   • Provides growth factors that promote healing
   • Minimizes pro-inflammatory effects
   • Better suited for conditions where inflammation may exacerbate symptoms

2. High leukocyte PRP (L-PRP):

   • Contains more inflammatory mediators
   • May cause increased local inflammation
   • Could potentially worsen muscle spasms through inflammatory pathways

Evidence for Muscle Applications

While direct evidence comparing leukocyte concentrations in PRP specifically for muscle spasms is limited, we can draw conclusions from related research:

• Studies on muscle regeneration show that PRP promotes better muscle regeneration and neovascularization in a dose-dependent manner 2
• The ISTH guidelines note uncertainty about PRP use for acute muscle injuries (median score of 5 on a 9-point scale), indicating this remains an area requiring further research 1
• A systematic review found that the overall evidence for PRP in acute muscle injuries is of low or very low quality 3

Clinical Application Guidelines

When using PRP for muscle spasms:

1. Preparation considerations:

   • The purity of the final PRP preparation should be reported, including white blood cell content 1
   • Platelet activation status prior to clinical use should be measured 1
   • The activation procedure should be documented 1

2. Administration protocol:

   • A single injection is most common (used in 65.5% of tendon studies) 4
   • Timing relative to injury should be considered, though optimal timing is not yet established

Potential Pitfalls and Limitations

• The evidence base for PRP in muscle conditions remains limited, with most studies focusing on tendon applications
• There is significant heterogeneity in PRP preparation methods across studies
• The VA/DoD clinical practice guidelines note inconsistent results for PRP in musculoskeletal applications 1
• Many studies lack proper controls, blinding, and standardization

Conclusion for Clinical Practice

For muscle spasms specifically, low leukocyte PRP is the preferred option over high leukocyte PRP due to the reduced inflammatory potential. However, clinicians should be aware that the overall evidence for PRP in muscle conditions remains limited, and results may vary based on preparation techniques and patient factors.