The biomechanical
and histological effects of platelet-rich plasma on fracture healing

Guzel Y, Karalezli N, Doral M, et al. Knee Surg Sports
Traumatol, Arthrosc.
2013 Oct 30 [Epub ahead of print].

Take Home
Message: The administration of platelet-rich plasma (PRP) using a standard preparation
technique may accelerate long bone fracture healing.

Platelets, which are naturally occurring in blood tissue,
secrete growth factors and cytokines that may enhance regenerative processes in
the body. Platelet-rich plasma (PRP) may be beneficial as an adjunct therapy
with spinal fusion surgery, prosthetic and periodontal therapy, and the
treatment of non-unions. However, there is still little known about the
biomechanical effects of PRP on the healing of fractures
. The aim of this prospective,
randomized animal study was to determine the effect of PRP on the fracture
healing of long bones. The authors divided 70 female rats into one of three
groups: no PRP group, PRP-added group, and control group (no fracture, no PRP).
Rats from the no PRP (n=30) and PRP-added (n=30) groups underwent mid-diaphysis
transverse femur fractures and had their fractures fixed with 1-mm K-wires. Only
the PRP-added group then received an autologous PRP injection in the fracture
line prepared as per a standardized protocol (Anitua technique). The authors performed histological
assessments at four weeks and nine weeks post-surgery to determine the extent
of bone recovery. Some rats also underwent biomechanical testing in the ninth
week post-surgery to assess the structural integrity of the bone (No-PRP group:
8 rats, PRP-added group: 8 rats, and control group: 10 rats). The authors found
that rats in the PRP-added group demonstrated earlier weight-bearing,
accelerated fracture healing (e.g. osteochondral bone formation, reorganization
of the cancellous bone), and were able to withstand more force when maximum
loading was applied to the bone, compared with rats that did not receive PRP. Interesting
to note, the femurs of the PRP-added group were as strong as the control
group’s femurs that were never fractured.

The results
of this study suggest that injection of PRP into a fracture site of a long bone
may speed recovery and increase the bone’s ability to withstand stress.
Although PRP injections have yet to be standardized into a most effective technique
and concentration, the Anitua technique used in this study shows promising
effects in the healing of fractures in long bones. However, clinicians should
keep in mind that this study was conducted on rats and not on human models. Furthermore,
this study did not look at the treatment of nonunions, a serious complication
in fracture healing, and so the effect of PRP on nonunions has yet to be
determined. Despite these limitations, these findings are intriguing and may
eventually prompt clinical trials to determine if PRP can accelerate fracture
healing or avoid nonunions in humans.

Questions for Discussion: What is your
experience as a clinician with PRP? Aside from PRP, what other therapeutic
interventions have you used to promote the healing of long bone fractures? Have
you found one intervention to be superior in terms of return-to-play/functionality
or incidence of re-fracture?

by: Tiffany Kobordo
by: Lisa Chinn and Jeffrey Driban


The Positive Effects of Different Platelet-Rich Plasma Methods on Human Muscle, Bone, and Tendon Cells

Guzel Y, Karalezli N, Bilge O, Kacira BK, Esen H, Karadag H, Toker S, Göncü RG, & Doral MN (2013). The biomechanical and histological effects of platelet-rich plasma on fracture healing. Knee Surgery, Sports Traumatology, Arthroscopy PMID: 24170188