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Comparison between two different platelet-rich plasma preparations and control applied during anterior cruciate ligament reconstruction. Is there any evidence to support their use?

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Introduction: To compare the clinical, analytical and graft maturation effects of two different platelet-rich plasma (PRP) preparations applied during anterior cruciate ligament (ACL) reconstruction. Materials and methods: A total of 150 patients with ACL disruption were included in the study. Arthroscopic ACL reconstruction with patellar tendon allograft was conducted on all knees using the same protocol. One hundred patients were prospectively randomised to either a group to receive double-spinning platelet-enriched gel (PRP) with leukocytes (n=50) or to a non-gel group (n=50). Finally, we included 50 patients treated with a platelet-rich preparation from a single-spinning procedure (PRGF Endoret(®) Technology) without leukocytes. Inflammatory parameters, including C-reactive protein (CRP) and knee perimeters (PER), were measured 24 hours and 10 days after surgery. Postoperative pain score (visual analogue score [VAS]) was recorded the day after surgery. Follow-up visits occurred postoperatively at 3, 6, and 12 months. The International Knee Documentation Committee scale (IKDC) was included to compare functional state, and MRI was conducted 6 months after surgery. Results: The PRGF group showed a statistically significant improvement in swelling and inflammatory parameters compared with the other two groups at 24 hours after surgery (p<0.05). The results did not show any significant differences between groups for MRI and clinical scores. Conclusions: PRGF used in ACL allograft reconstruction was associated with reduced swelling; however, the intensity and uniformity of the graft on MRI were similar in the three groups, and there was no clinical or pain improvement compared with the control group. Level of evidence: II.
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Injury, Int. J. Care Injured 45SX (2014) SX–SX
Introduction
The rest period required following surgical treatment of
rupture of the anterior cruciate ligament (ACL) is often very
long. Different methods have been evaluated in an attempt to
shorten the time required for the graft to acquire biomechanical
properties similar to those of the original ACL [1].
ACL reconstruction with grafts is usually successful and
predictable [2]. Various aspects of reconstruction, such as graft
options, tunnel placement, tensioning and fixation techniques,
are being revised repeatedly to improve the results. Nevertheless,
the healing process of ligament and tendon is extremely complex
and not fully understood [3-7]. Platelet-rich plasma (PRP)
has been recognised as a powerful adhesive and haemostatic
agent and a potent source of autologous growth factors [8-12].
Consequently, there has been strong clinical interest in the use
of PRP as an aid in tissue regeneration.
The use of PRP treatment has become more widespread in
sports medicine [3,5,13-16], mainly because of the advantage of
using the patient’s own growth factors, and ease of preparation
[3,5]. Some studies in ACL reconstruction have reported
favourable clinical outcomes using different PRP treatments
[16-18], whereas others found no advantages [19-21].
There is insufficient scientific evidence from current research
to prove the safety and effectiveness of PRP treatment [1]. Most
of the published research comprises case reports or case-series
studies that have no control group or that have insufficient
sample sizes to enable calculation of statistical significance:
more research is needed using randomised double-blind
methods [5,22,23].
We hypothesised that PRP may improve the outcome of ACL
reconstruction by enabling better graft remodelling, immediate
K E Y W O R D S
Platelet-rich plasma
Anterior cruciate ligament reconstruction
Graft maturation
ABSTRACT
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To compare the clinical, analytical and graft maturation effects of two different platelet-
rich plasma (PRP) preparations applied during anterior cruciate ligament (ACL) reconstruction.
M
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A total of 150 patients with ACL disruption were included in the study.
Arthroscopic ACL reconstruction with patellar tendon allograft was conducted on all knees using
the same protocol. One hundred patients were prospectively randomised to either a group to receive
double-spinning platelet-enriched gel (PRP) with leukocytes (n=50) or to a non-gel group (n=50).
Finally, we included 50 patients treated with a platelet-rich preparation from a single-spinning
procedure (PRGF Endoret® Technology) without leukocytes.
Inflammatory parameters, including C-reactive protein (CRP) and knee perimeters (PER), were
measured 24 hours and 10 days after surgery. Postoperative pain score (visual analogue score [VAS])
was recorded the day after surgery. Follow-up visits occurred postoperatively at 3, 6, and 12 months.
The International Knee Documentation Committee scale (IKDC) was included to compare functional
state, and MRI was conducted 6 months after surgery.
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The PRGF group showed a statistically significant improvement in swelling and inflammatory
parameters compared with the other two groups at 24 hours after surgery (p<0.05).
The results did not show any significant differences between groups for MRI and clinical scores.
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PRGF used in ACL allograft reconstruction was associated with reduced swelling; however,
the intensity and uniformity of the graft on MRI were similar in the three groups, and there was no
clinical or pain improvement compared with the control group.
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© 2014 Elsevier Ltd. All rights reserved.
Comparison between two different platelet-rich plasma preparations and
control applied during anterior cruciate ligament reconstruction. Is there any
evidence to support their use?
A. Valentí Azcárateaa,*, J Lamo-Espinosaa, D Aquerretab, M Hernandezc, G Moraa, JRValentí Nina
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* Corresponding author at: Orthopedic Surgery and Traumatology, Clínica
Universidad de Navarra, Av. Pio XII, 36. 31008 Pamplona Spain. Tel.: +34 948 255
400; fax: + 34 948 296 500.
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avalazc@gmail.com (A. Valentí Azcáratea).
0020-1383/$ – see front matter © 2014 Elsevier Ltd. All rights reserved.
Contents lists available at SciVerse ScienceDirect
Injury
journal homepage: www.elsevier.com/locate/injury
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postoperative rehabilitation or an earlier return to sports
activities. To test this hypothesis, we compared clinical, analytic
and MRI results of two different PRP systems (PRGF® and PRP
with white blood cells) with those of a control group.
Methods
Based on a previous randomised, double-blind trial [20] we
decided to conduct a new comparison with two different PRP
systems.
Patient inclusion criteria were as follows: diagnosis of ACL
disruption established by an orthopaedic surgeon, including
laxity assessment by the Lachman test, pivot-shift test, and MRI
studies; no prior knee surgery; and normal contralateral knee.
Patients with previous knee pathology or symptoms before ACL
rupture were excluded. All patients were informed about the
purpose of the study and provided informed consent. No patient
refused to participate.
One hundred patients undergoing arthroscopic ACL recon-
struction were randomised using a computer programme into two
groups: 1) the control group comprised 50 patients with patellar
tendon allograft reconstruction and 2) the PRP group comprised
50 patients with patellar tendon allograft reconstruction and
platelet-enriched gel with leukocytes. The results from these two
groups were published. A third group was added for the current
study: this group comprised 50 more consecutive patients with
patellar tendon allograft reconstruction and platelet-enriched
gel (PRGF-Endoret®) [20].
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According to the literature, platelet-rich concentrate should
have a 2- to 5-fold increase in platelet concentration over
baseline [24]. The patients in the current study had a baseline
blood platelet count of 201×106/ml.
One hour before surgery, 40 ml of blood was collected into
sterile sodium citrate tubes 3.8% (wt/vol) in the PRP and PRGF
groups (for every 9 ml of blood, we obtain 2 ml of platelet-
enriched gel).
The first method for obtaining PRP was a double-spin
procedure using a standard centrifuge technique (Beckman
J-6B, Beckman Coulter Spain, Madrid, Spain; 8 minutes at
3,000 rpm [2,217
g
] and 6 minutes at 1,000 rpm [380
g
]) with
a mean platelet concentration of 837×106/ml (469% increase)
with platelet recovery of 63.8% from patient blood and a mean
leukocyte concentration of 8,100/!l. We obtain one pipette with
PRP (including leukocytes and some blood cells) and another
with platelet-poor plasma. To initiate clotting, calcium chloride
10% (0.05 ml of calcium chloride per ml PRP) was added to the
liquid PRP aliquots just before administration.
The second method for obtaining PRP involved following
Anitua´s technique (PRGF-Endoret® Technology) using centrifu-
gation at 580
g
for 8 minutes at 1,800 rpm at room temperature
(BTI System II; BTI Biotechnology Institute, Vitoria, Spain). The
top volume of plasma, with a platelet count similar to peripheral
blood (242×106/ml), was separated and deposited in a collection
tube and calcium chloride (10% wt/vol) added in the operating
room to cause formation of a biocompatible fibrin that was
applied at the tibial tunnel.
The plasma fraction, located just above the sedimented red
blood cells but not including the buffy coat, was collected in
another tube. This plasma contains a moderate enrichment
in platelets (504×106/ml; 2- to 3-fold the platelet count of
peripheral blood) with no leukocytes. Pipetting was carried out
with extreme care to avoid inflammation under a laminar flow.
Thereafter, in the operating room 10% calcium chloride was
added to activate platelets to release growth factors (0.05 ml of
calcium chloride per ml PRP). Within approximately 15 minutes,
the coagulum had solidified and the gel obtained.
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All ACL reconstructions were performed by the same surgical
team, using the same anaesthetic technique (general anaesthesia
with a laryngeal mask) and with tourniquet ischaemia of
300 mm Hg. Arthroscopy was conducted to repair associated
lesions, then the ACL was reconstructed using a patellar tendon
allograft transtibial technique with femoral tunnel at the 10 or
11 o’clock position for a right knee and the 1 or 2 o’clock position
for the left knee, and immediately anterior to the over-the-top
position, leaving a 1 to 2-mm posterior cortical wall with a
RigidFix technique (DePuy Mitek, Raynham, MA) [25] with two
biodegradable cross pins to fixate the femoral bone and a tibial
biodegradable (Byocril) interference screw.
All meniscal repairs were performed with all-inside methods
(FasT
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Fix Meniscal Repair System Smith & Nephew Endoscopy,
Andover, MA).
In the PRP group the ligament was covered with the platelet-
rich gel and sutured over itself with gel in its interior. After
activating the poor platelet concentration we obtained a gel that
was introduced after implantation of the graft inside the tibial
tunnel, after shutting off the water. No technical variation was
needed at any time.
In the PRGF-Endoret® group, activated liquid PRGF was injected
into the graft before implantation and the biocompatible fibrin
was applied into the tibial tunnel at the end of surgery (Figure 1).
F
ig. 1. (A) Clot of PRP after activation was placed on the tibial tunnel at the end of surgery. (B) PRGF injection inside the allograft after addition of calcium chloride 10%.
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Patients were immobilised with a knee brace after the
operation and were treated with non-steroidal anti-inflammatory
drugs according to a set protocol. Ten days after the operation,
the whole range of movement was allowed. Cycling was allowed
at 2 to 3 months after surgery, straight-line running at 4 months,
and contact sports at 6 months.
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Follow-up visits were scheduled preoperatively and post-
operatively at 3, 6, and 12 months and yearly thereafter. Clinical
and inflammatory measurements were recorded by a physician
who was not involved in the study.
A pain visual analogue scale (VAS) was used to serially assess
postoperative pain the day after surgery. Scores ranged from 0 (no
pain) to 10 (maximum pain). Anterior laxity was measured with a
KT-1000 arthrometer (MEDmetric, San Diego, CA). The objective
questionnaire-based International Knee Documentation
Committee scale (IKDC) was included to compare the functional
state [26].
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The C-reactive protein (CRP) level was measured 24 hours
after surgery (CRP 1) and 10 days after surgery (CRP 2). The
perimeter in the middle of the kneecap was measured using a
metric tape before and 24 hours after surgery and the difference
was determined (PER 1). A second perimeter was measured
5 cm above the top edge of the kneecap before and 24 hours after
surgery and the difference was obtained (PER 2).
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A double-blind study of MRI with an independent radiologist
was performed at 6 months after surgery to evaluate the status
of the ACL grafts. The MRI examinations included orthogonal
proton density-weighted axial, sagittal, and coronal images and
T1 and T2-weighted images, which were orientated parallel
to the course of the femoral intercondylar roof. The ACL grafts
in all groups were evaluated by MRI using direct signs, such
as thickness, intensity, and uniformity of the graft and tunnel
direction, as well as indirect signs, including tibial anterior
translation and position of the posterior cruciate ligament (PCL)
[27].
The results were compared between groups. Anterior tibial
displacement can be measured by drawing a vertical line that is
tangential to the posterior cortex of the lateral femoral condyle
and by measuring the distance from this line to the posterior
cortex of the lateral tibial plateau. This measurement is normally
less than 5 mm, with greater than 7 mm indicating abnormality
and 5 to 7 mm being an equivocal finding [28].
Tunnel placement and graft position in the tibia and femur
were evaluated using the method of McCauley [29].
The tunnel in the tibia should be behind a line drawn along
the roof of the femoral notch (oblique line), and the centre of the
graft tunnel should be one-quarter to one-half of the distance
from the anterior tibial cortex to the posterior tibial cortex.
The femoral tunnel should be behind a point formed by a line
drawn along the posterior femoral cortex and a line drawn along
the roof of the intercondylar notch. We evaluated tunnels as
correctly placed, anterior, or posterior.
Intensity, uniformity and thickness were measured at the
centre of the graft with proton density-weighted and T2-
weighted images. A normal ACL has low signal intensity on either
image. The intensity of the graft was measured with a region-of-
interest (ROI).
The PCL angle was the angle measured between a line through
the centre of the distal portion of the ligament and a vertical
perpendicular line through the tibial plateau.
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Statistical analysis was performed with SPSS software, version
15.0 (SPSS, Chicago, IL). Repeated measure ANOVA or two-tailed
t-tests were used; the Bonferroni method was employed to
adjust p-values in case of multiple testing. Data are expressed
as mean ± SD.
A p-value of less than 0.05 was considered significant.
R
esults
Demographic data and associated injuries were comparable
between groups. The mean age was 26.9 years (SD, 9) (Table 1).
The mean follow-up was 24.3 months (SD, 4) (range, 18 to 36
months). No patients were lost to follow-up. The mean operative
time was 68 min (48-115 min).
All laboratory results and clinical parameters are shown in
Table 2.
No severe adverse events were observed during the treatment
and follow-up periods.
The PRGF group showed a statistically significant improvement
in swelling scores 24 hours after surgery (CRP 2 p=0.003 and
PER 1 p=0.02 PER 2 p=0.001) compared with the PRP and control
groups (Figure 2). No significant differences in functional results
were found at the final follow-up.
There were no statistically significant differences between the
three groups in CRP 1 (p=0.742) and VAS (p=0.379) at 24 hours
after surgery (Figure 3).
There were no significant differences in the range of knee
motion, muscle torque, KT-1000 or IKDC score. The pivot-shift
test was negative in 95% of patients.
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There were no statistically significant differences between
groups in intensity, thickness, and uniformity of graft; the
direction of the tibial and femoral tunnels; tibial anterior
translation; and other parameters described in the Methods
section (p=0.233).
The mean angle of the ACL in the control group was 66° (range,
39° to 75°), in the PRP group the graft angle was 67° (range, 43°
T
able 1
Demographic data for the three study groups
Control PRP group PRGF
group (with leukocytes) group
Age (yr) 26.1 (15-59) 26.1 (14-57) 27.4 (16-50) NS
Sex 12 F 10F 7F NS
38M 40M 43M
Associated ACL without ACL without ACL without NS
procedures lesions 22 lesions 20 lesions 16
Partial Partial Partial
meniscectomy 14 meniscectomy 13 meniscectomy 17
Meniscal Meniscal Meniscal
repair 10 repair 14 repair 18
Microfractures 4 Microfractures 3 Microfractures 2
NS, no statistical significance (p>0.05); F, female; M, male.
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to 73°) and in the PRGF group the graft angle was 65º (range 45º
to 77º) (p=0.734).
There were no differences in the thickness of the graft
between groups: mean diameter was 8 mm (range, 5 to 12 mm)
in the control group; 9 mm (range, 5 to 12 mm) in the PRP group,
and 8 mm (range, 6 to 11 mm) in the PRGF group.
Tibial anterior translation in the control group was normal
in 16 patients, between 5 and 7 mm in seven patients, and over
7 mm in two patients. The mean anterior displacement of the
tibia in the control group was 4.5 mm (range, 2 to 9 mm). In the
PRP group, tibial translation was normal in 18 patients, between
5 and 7 mm in six patients, and over 7 mm in one patient. In
this group the mean was 4.2 mm (range, 3 to 8 mm). In the PRGF
group, tibial anterior translation was normal in 17 patients,
between 5 and 7 mm in six patients, and over 7 mm in one
patient, with no statistically significant differences (p=0.534).
The PCL angle was 11° in the control group (range, 0° to 27°);
14° in the PRP group (range, 3° to 27°) and 13° in the PRGF group
(range, 5° to 30°) (p=0.457).
Signal intensity of the ACL graft on proton density–weighted
images showed a mean of 190 ROIs in the control group, 230 ROIs
in the PRP group and 219 ROIs in the PRGF group (p=0.454).
On T2-weighted images, the mean number of ROIs was 61 in
the control group, 75 in the PRP group and 70 in the PRGF group
(p=0.35).
Regarding the uniformity and internal striation of the graft,
in the control group 13 ACL showed a homogeneous pattern
and 12 had some degree of heterogeneity or graft striation (8
slightly and 4 moderately). In the PRP group 12 patients had
homogeneous pattern and 13 had some degree of heterogeneity
(9 slightly and 4 moderately). In grafts treated with PRGF, 11
were absolutely homogeneous and 14 showed heterogeneity
(9 slightly, 4 moderately and 1 severely) within the graft. No
significant differences were found between the groups.
All tunnel directions were correctly placed in the control
and PRGF groups, whereas one femoral tunnel in grafts treated
with PRP was placed anteriorly, with no statistically significant
difference.
Discussion
The lengthy recovery time after ACL before normal sporting
activity can be resumed is mainly because of the very slow graft
healing in the bone tunnels and ligamentisation of the intra-
articular part of the graft. This complex graft healing process
is influenced by multiple surgical and postoperative variables.
Research into biological approaches that may improve graft
incorporation has attracted attention, but these procedures have
no benefit without a suitable surgical technique and correct graft
stability [20].
PRP is a possible treatment option for the stimulation and
acceleration of soft-tissue healing and regeneration [30].
Procedures involving PRP and their pools of growth factors are
being increasingly used, although there is insufficient medical
T
able
2
Laboratory and clinical parameters for the three study groups
KT-1000 KT-1000
CRP 1 CRP 2 PER1 PER2 before surgery after surgery
(mg/dL)* (mg/dL)* VAS (cm) (cm) (mean) (mean) IKDC
Control group 1.22 0.85 2.30 2.6 2.3 5 0.5 70%A,
(0.1 to 4.4) (0.07 to 3.8) (1 to 7) (2 to 7) (-2 to 3) 26%B,
4%C
PRP group (with leukocytes) 1.14 0.88 2.58 2.6 1.9 4 0.5 70%A,
(0.1 to 4.8) (0.03 to 5.5) (1 to 7) (2 to 7) (-2 to 3.5) 30%B
PRGF group 1.12 0.41 2 1.5 1.04 4.5 0.8 64%A,
(0.02-2.9) (0.02-1.8) (1-8) (2 to 6) (0 to 3) 34%B,
2%C
No statistically significant differences (p>0.05) were found for comparisons.
Abbreviations: VAS, visual analogue scale; IKDC, International Knee Documentation Committee.
*The normal value is less than 1 mg/dL.
F
ig.
2
. The PRGF group showed a statistically significant improvement in swelling scores 24 hours after surgery compared with the PRP and control groups.
CRP: mg/dL; PER: centimetres.
F
ig. 3. No significant differences in CRP 1 and VAS were found at 24 hours after surgery.
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evidence of their effectiveness, and their real potential has still
not been demonstrated [31]. Indications for PRP procedures are
becoming more and more exaggerated.
The number of PRP-related articles published in PubMed is
increasing: 10 articles in 2009, 168 articles in 2010, and 248
articles in 2011. It is difficult to compare the results of these
articles because of the lack of uniformity in terms of platelet
system recovery processing and variability of techniques and
application.
The current study was designed to compare the effects of
two different PRP preparations and provide clinical evidence
that could theoretically help to enhance the natural graft
healing process in ACL reconstruction. The study compares
the experiences documented by one surgery team using two
different platelet concentrates and a control group. The effects
of PRP compared with control group in ACL reconstruction have
been reported [20,21,32], but this is the first clinical comparison
between two different PRP preparations in ACL reconstruction.
There is only one study with a similar methodology in
osteoarthritis (OA) [33].
The anaesthetic procedure, operative technique, and post-
operative management protocol were consistent throughout the
current study, thus reducing variability and strengthening the
study. The study groups had similar demographic backgrounds
and associated lesions.
There were no statistically significant differences in
functional outcome, graft healing on MRI, or complications.
The only statistically significant differences were found for the
inflammatory parameters PER1 and PER2 the day after surgery
and CRP 2 ten days after surgery in the PRGF group. These results
are consistent with the data reported by Yoshida, who studied
the anti-inflammatory effects of PRP in the ACL fibroblast in vitro
[30].
Analysis of the inflammatory parameters shows that PRGF
statistically significantly decreased knee perimeters (PER1
and PER2) compared with PRP and control. Likewise, PRGF
significantly reduced CRP 2 ten days after surgery compared
with the other two groups. We did not find differences in CRP 1
and VAS. This result could be interpreted as PRGF has a delayed
action after surgery. To our knowledge, no randomised controlled
study has so far been conducted to investigate the effects of PRGF
on inflammatory parameters in ACL surgery.
These findings are different to those in the presence of
leukocytes. The role of leukocytes is complex and not well
understood. The presence of leukocytes can provide a theoretical
advantage in preventing infection but may also impede tissue
healing by increasing inflammation [9,34]. Our results showed
decreased inflammation in the PRGF group (leukocyte depletion)
with no differences between PRP (with leukocytes) and the
control group. More studies are needed to establish the role of
leukocytes in PRP therapy.
The outcome of PRP treatment has been suggested to be age-
dependent, with ACL fibroblasts from young patients having
better cellular migration and proliferation than those from older
patients [35]. Young children are therefore expected to derive
greater benefit from PRP application than adolescents or adults.
The mean age of the subjects in the current study was nearly 27
years old and our results did not show any differences, although
there were only five open physis patients in this study.
Weiler [36] and Anderson [37] showed that MRI signal
intensity may be correlated with graft maturation in animal
models. Both authors proved that the addition of growth factors
(platelet-derived growth factor [PDGF], bone morphogenetic
protein [BMP], and transforming growth factor [TGF]) improved
the structural and mechanical properties of a free tendon graft in
ACL reconstruction.
Radice [17] demonstrated a 48% reduction in the time
required to achieve a complete homogeneous graft MRI signal,
when PRP was used for the surgical ACL procedure. Anitua [38]
described an experimental study that PRGF-Endoret® stimulates
migration of tendon cells and synovial fibroblasts. They assume
a ligamentisation benefit on ACL surgery.
There were no statistically significant differences in MRI
results between the control group and the PRP groups. From
the results, it is not possible to confirm whether PRP influences
imaging appearance of the graft at 6 months after surgery.
Functional scores support the findings on MRI; there were no
statistically significant differences in IKDC results.
There are still many controversial questions. Is it necessary
to use PRP treatments during ACL surgery for the one purpose
of reducing inflammatory parameters? How long does their
effect last? Short-term results on ACL surgery can be attributed
to PRP, but it is hard to imagine how one isolated application at
the time of surgery is sufficient to produce effects for months
and to enable conclusions to be drawn about its beneficial action.
Repeat injections of these factors during the postoperative
recovery and rehabilitation process may enable conclusions to
be drawn about their use and any long-term benefit.
Each surgeon has to consider whether a reduction in the
inflammatory parameters in the first postoperative days
justifies the use of PRGF on ACL reconstruction, even though
this associated technique is a simple, non-invasive and low cost
method.
There were some potential limitations to the current study.
The patients who received PRGF were not randomly assigned
because this group was included after the results of the previous
study were published [20]. Although the sample size was fairly
small, we believe the study has sufficient statistical power.
The images of ACL on MRI as a reflection of indirect maturation
criteria were difficult to interpret and no conclusions could be
made. Histological analysis would support the findings, but it
would be unethical to take a “second look” arthroscopy.
It is difficult to extrapolate our results to autografts; however,
it is not the purpose of our study to demonstrate the well-known
effectiveness of fresh frozen allografts as this has been well
established in multiple studies [39-42].
C
onclusions
Although the use of these autologous elements does not
expose the patients to a higher risk, PRP can be considered only
as a potential therapy during ACL surgery. More evidence from
well run studies is required to support the promising results in
the field of sport medicine. Further research into the application
of PRP is also needed to specify dosage, location and timing of
injection.
In our experience, PRGF decreased the inflammatory para-
meters (CRP and knee perimeters) in the short-term postoperative
reports, but there did not appear to be any benefit of the use of
double spinning and leukocyte PRP systems on ACL surgery.
We have not been able to demonstrate any kind of benefit on
graft maturation analysed by MRI, faster full recovery or early
return to sports.
C
on
f
lict o
f
interest statement
The authors declare that they have no conflict of interest.
R
e
f
erences
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... The internal fixation methods in the femoral and tibial tunnels were reported in 14 studies. 20,26,[28][29][30][31][33][34][35][36][37][38][39][40] The cross-pin, EndoButton device, and interference screw were used for femoral tunnel fixation in 10, 20,28-31,33,35,36,39,40 two 26,34 and two 37,38 studies respectively, while interference screw was used for all of the tibial tunnel fixation. Detailed rehabilitation protocols were available in 11 studies. ...
... Detailed rehabilitation protocols were available in 11 studies. 20,[26][27][28][29][30][33][34][35][36]38 Knee bracing (or plaster splint in one study 38 ) was applied for early immobilization in four studies, 20,26,28,36 and accelerated rehabilitation protocols were applied without using of knee braces in the other six studies. 27 of funding sources of each trial is available in Supporting information Appendix S4. ...
... Detailed rehabilitation protocols were available in 11 studies. 20,[26][27][28][29][30][33][34][35][36]38 Knee bracing (or plaster splint in one study 38 ) was applied for early immobilization in four studies, 20,26,28,36 and accelerated rehabilitation protocols were applied without using of knee braces in the other six studies. 27 of funding sources of each trial is available in Supporting information Appendix S4. ...
Article
Full-text available
This study aimed to identify the effectiveness of platelet-rich plasma (PRP) for patients operated with anterior cruciate ligament reconstruction (ACLR). Databases of PubMed, Embase, and CENTRAL were independently retrieved by two authors, for identifying the eligible randomized controlled trials (RCTs) comparing the clinical and imaging outcomes of ACL reconstructed patients augmented with or without PRP. The Cochrane Collaboration tool was utilized to assess the risk of bias of the included trials. We qualitatively synthesized the outcomes include the image evaluations on the healing of bone tunnels, graft remodeling, donor site healing and tunnel widening, and clinical evaluations on knee stability and function, pain symptom by visual analogue scale (VAS), inflammatory parameters and so on. A total of 16 RCTs, including 1025 patients, were included for eligibility. Generally, the included studies were of low risk of bias, but the conducting of allocation concealment was not clearly described in many studies. Three imaging techniques, including MRI, CT and ultrasound, were selected in these trials. Significant improvement on graft remodeling, bone tunnel healing, harvest site healing and bone tunnel diameters were demonstrated in one of five (20.0%), three of five (60.0%), two of four (50.0%) and one of five (20.0%) studies respectively, for PRP group. Various clinical outcomes, such as IKDC score, Lysholm score, Tegner score, knee anteroposterior and rotational laxity, range of motion and VAS, could not be improved with PRP application. The PRP is associated with very limited role in improving knee outcomes following ACLR, and there is no indication for PRP procedures in ACLR at this stage.
... However, they fixed their graft at the femoral side by Swing-bridge and on the tibial side by Evolgate interference screw with a fixed diameter of 9.5 mm. In the study done by Azcárate et al. [28], all ACL reconstructions were performed by the same surgical team, using general anaesthesia. They used patellar tendon allograft for ACL reconstruction. ...
... In the study done Komzák et al., the functional status of knee was evaluated at 3 and 12 postoperative months [29]. In the study done by Azcárate et al., the follow-up of the patients was 18 months, with a mean of 24.3 months (range: 18 to 36 months) [28]. ...
... In the study done by Vadalà et al., the mean age of all 40 subjects was 34.5 years (range: 18-48 years) [27]. In the study done by Azcárate et al., non-PRP group comprised 50 patients with mean age of 26.6 years (range: 15 to 59 years) [28]. PRP group comprised 50 patients with mean age of 26.1 years (range: 14 to 57 years). ...
Article
Aims and objectives: To measure the additional effect of platelet-rich plasma (PRP) on functional outcome of anterior cruciate ligament tear managed by augmenting anterior cruciate ligament (ACL) reconstruction with PRP. Methods: The present study was conducted on patients with ACL tear admitted in the department of orthopaedics, King George's Medical University, Lucknow wherein a total of 70 subjects were assigned into two groups of 35 patients each randomly, viz Group 1 in which the patients were treated by quadruple hamstring graft alone and Group 2 in which the patients were treated with augmented hamstring graft with PRP. The standardized anterior drawer test, Lachman's test, Lysholm knee score were quantified both preoperatively and postoperatively at different follow-ups and also tibial tunnel widening was measured postoperatively at different follow-ups. Result: The present study had 70 patients with ACL tears. The mean age of patients in non-PRP groups was 29.71 ±2.99 years while that in the PRP group was 28.34±4.32 years. On comparing the improvement in grades at pre-op, immediate postop, 6 weeks, and 3 months follow-ups, there was no statistically significant difference between the two groups. The tibial tunnel widening also showed no significant difference between the two groups. Conclusion: In our study, it was found that both the groups showed improvements in grades of anterior drawer test and Lachman's test postoperatively but the difference between both the groups was not significant. Similarly, while comparing the improvements in Lysholm knee score and tibial tunnel widening among both the groups, the difference was not significant. Follow up of 3 months was a limiting factor in our study. This technique needs further clinical evaluation to assess the long-term results.
... The remaining 21 studies with full-text were further evaluated for eligibility, 4 of which were removed due to non-RCT and duplicates. Finally, 17 articles [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46] were deemed eligible based on our inclusion criteria and were included in our systematic review. The detailed flow chart of the document search was shown in Figure 1. ...
... We concluded main characteristics of the 17 studies included in our study (Supplemental Table I). Of these studies, 10 studies were conducted in European countries including 4 from Spain [34,37,38,42], 3 from Italy [33,35,46], 1 from Slovenia [39], 1 from Greece [36] and 1 from Czech [30], 3 studies were conducted in China [31,40,44] and the remaining 4 studies were conducted in Brazil [45], Iran [43], Chile [41] and USA [32], respectively. The sample sizes of selected studies varied from 20 to 112 and 970 subjects in total were included in our present systematic review: 482 participants in control group and 488 participants in PRP groups. ...
... All the studies reported baseline similarities with regard to gender distribution and age of participants. In term of graft option for ACL reconstruction, HS and BPTB autograft were the most common choices except 2 studies using fresh-frozen allograft [34,42]. In all studies, follow-up time varied from 3 months to 24 months, and the average follow-up time was 11.7 months. ...
Article
Full-text available
Anterior cruciate ligament (ACL) rupture is a common musculoskeletal injury, most frequently affecting young and physically active patients. Platelet-rich plasma (PRP) has been widely used in ACL reconstruction to augment the graft healing. However, high-level studies addressing its clinical efficacy could not reach a consensus. In this study, we assess the efficacy of PRP on pain relief, functional improvement along with radiological changes in patients who underwent ACL reconstruction. We performed comprehensive literature search and included 17 RCTs containing 970 participants who underwent ACL reconstruction. The combined data showed significant difference between PRP and control with regard to VAS score (MD: -1.12, 95% CI -1.92, -0.31; P = .007), subjective IKDC score (MD: 6.08, 95% CI 4.39, 7.77; P < .00001) and Lysholm score (MD: 8.49, 95% CI 1.63, 15.36; P = .02) by postoperative 6 months, but only pain reduction was deemed clinically important. At the end of one year's follow-up, no clinically meaningful improvement in VAS (MD: -0.47, P = .04), subjective IKDC score (MD: 3.99, P = .03), Lysholm score (MD: 2.30, P = .32), objective IKDC score (RR: 1.03, P = .09) and knee joint laxity (MD: 0.17, P = .28) was seen. In terms of radiological findings, about one-third of the studies favored PRP to facilitate the graft healing, improve the harvest site morbidity and prevent tunnel widening. In summary, moderate quality of evidence suggested that PRP could provide short-term but not long-term clinically important pain reduction.
... Alternatively, these effects could be dependent upon the composition of PRP. Azcarate et al. [36], who furthered the work of Valenti Nin et al. [22], added another intervention group; PRP without leukocytes. This form was found to significantly reduce CRP and swelling suggesting that it had more potent anti-inflammatory effects. ...
... This suggests PRP increases the early rate of ligamentization. However, results from Valenti Nin et al. [22] showed no significant difference at the 6-month mark; congruent with later research by Azcarate et al. [36]. ...
Article
Full-text available
Purpose To systematically review the effect of PRP on healing (vascularization, inflammation and ligamentization) and clinical outcomes (pain, knee function and stability) in patients undergoing ACL reconstruction and compare the preparation and application of PRP. Methods Independent systematic searches of online databases (Medline, Embase and Web of Science) were conducted following PRISMA guidelines (final search 10th July 2021). Studies were screened against inclusion criteria and risk of bias assessed using Critical appraisal skills programme (CASP) Randomised controlled trial (RCT) checklist. Independent data extraction preceded narrative analysis. Results 13 RCTs were included. The methods of PRP collection and application were varied. Significant early increases in rate of ligamentization and vascularisation were observed alongside early decreases in inflammation. No significant results were achieved in the later stages of the healing process. Significantly improved pain and knee function was found but no consensus reached. Conclusions PRP influences healing through early vascularisation, culminating in higher rates of ligamentization. Long-term effects were not demonstrated suggesting the influence of PRP is limited. No consensus was reached on the impact of PRP on pain, knee stability and resultant knee function, providing avenues for further research. Subsequent investigations could incorporate multiple doses over time, more frequent observation and comparisons of different forms of PRP. The lack of standardisation of PRP collection and application techniques makes comparison difficult. Due to considerable heterogeneity, ( I ² > 50%), a formal meta-analysis was not possible highlighting the need for further high quality RCTs to assess the effectiveness of PRP. The biasing towards young males highlights the need for a more diverse range of participants to make the study more applicable to the general population. Trail registration CRD42021242078CRD, 15th March 2021, retrospectively registered.
... In a randomized controlled trial, 1 year after ACLR the administration of PRP was related to a decrease in swelling 24 h after the surgical procedure. However, no difference in the IKDC scores or radiologic graft healing between PRP and control groups was found [63]. Komzak et al. encountered no difference in the functional scores between patients and controls in a prospective study evaluating the impact of PRP on graft healing [64]. ...
Article
Full-text available
Surgical reconstruction in anterior cruciate ligament (ACL) ruptures has proven to be a highly effective technique that usually provides satisfactory results. However, despite the majority of patients recovering their function after this procedure, ACL reconstruction (ACLR) is still imperfect. To improve these results, various biological augmentation (BA) techniques have been employed mostly in animal models. They include: (1) growth factors (bone morphogenetic protein, epidermal growth factor, granulocyte colony-stimulating factor, basic fibroblast growth factor, transforming growth factor-β, hepatocyte growth factor, vascular endothelial growth factor, and platelet concentrates such as platelet-rich plasma, fibrin clot, and autologous conditioned serum), (2) mesenchymal stem cells, (3) autologous tissue, (4) various pharmaceuticals (matrix metalloproteinase-inhibitor alpha-2-macroglobulin bisphosphonates), (5) biophysical/environmental methods (hyperbaric oxygen, low-intensity pulsed ultrasound, extracorporeal shockwave therapy), (6) biomaterials (fixation methods, biological coatings, biosynthetic bone substitutes, osteoconductive materials), and (7) gene therapy. All of them have shown good results in experimental studies; however, the clinical studies on BA published so far are highly heterogeneous and have a low degree of evidence. The most widely used technique to date is platelet-rich plasma. My position is that orthopedic surgeons must be very cautious when considering using PRP or other BA methods in ACLR.
... The remodeling stage is finished by 9 months at the earliest [20,34], and ligamentization could be observed after 2 years [8]. In the clinic, patients are usually recommended to return to low and moderate intensity exercise after 6 months [35][36][37], and typically regain about 85% function eventually [38]. Hence, a safe and effective approach to expedite the healing process is needed to restore the natural biomechanics of tendon, which is required for rapid return to preinjury activity levels. ...
Article
Full-text available
Graft regeneration after anterior cruciate ligament (ACL) reconstruction surgery is a complex three-stage process, which usually takes a long duration and often results in fibrous scar tissue formation that exerts a detrimental impact on the patients' prognosis. Hence, as a regeneration technique, stem cell transplantation has attracted increasing attention. Several different stem cell types have been utilized in animal experiments, and almost all of these have shown good capacity in improving tendon-bone regeneration. Various differentiation inducers have been widely applied together with stem cells to enhance specific lineage differentiation, such as recombinant gene transfection, growth factors, and biomaterials. Among the various different types of stem cells, bone marrow-derived mesenchymal stem cells (BMSCs) have been investigated the most, while ligament stem progenitor cells (LDSCs) have demonstrated the best potential in generating tendon/ligament lineage cells. In the clinic, 4 relevant completed trials have been reported, but only one trial with BMSCs showed improved outcomes, while 5 relevant trials are still in progress. This review describes the process of ACL graft regeneration after implantation and summarizes the current application of stem cells from bench to bedside, as well as discusses future perspectives in this field.
... What is more, both restoration of full knee extension and 90 degrees knee flexion occurred earlier in the PRP group. This stands in contrast to the study of Azcárate et al., who showed no significant difference in the range of knee motion when adding PRP to the ACLR [18]. Such outcomes of our study could result from earlier walking without crutches. ...
Article
Full-text available
Background: Using Platetet-Rich Plasma (PRP) in anterior cruciate ligament reconstruction (ACLR) has been suggested to improve patient outcomes. The aim of this study was to assess the impact of PRP administration on pain, range of motion (ROM) restoration and the functional results of ACLR performed with quadriceps tendon bone (QTB) autografts. Methods: A total of 106 patients were included in this multicenter study. Fifty-two patients underwent single-bundle QTB ACLR and 54 patients underwent the same procedure with additional PRP administration. Results: Mean time of need for on-demand analgesia was 8 days in the PRP group and 11 days in no-PRP group. Symmetric full extension was restored in a mean of 40 days in the PRP group and 53 days in the no-PRP group. Ninety degrees of flexion was restored at a mean of 21 days in the PRP group and 25 days in the no-PRP group. At 18 months postoperatively, the mean side-to-side difference in anterior tibial translation with the use of an arthrometer (Rolimeter, Aircast Europa) was 1.3 mm in the PRP group vs. 2.7 mm in the no-PRP group. Mean tibial tunnel widening was 1.4 mm in the PRP group vs. 2.1 mm in the no-PRP group. The mean score in the pain section of the KOOS scale was 93 in the PRP group vs. 89 in the no-PRP group. For the IKDC scale, 53 patients in the PRP group graded A or B and 1 patient graded C. In the no-PRP group, 48 patients graded A or B and 4 patients graded C or D. Conclusions: The use of PRP in QTB ACLR may decrease the need for on-demand analgesia and accelerate ROM restoration as well as improve knee stability, lessen the extent of tibial tunnel widening and potentially diminish pain at 18 months postoperatively. Further studies will be needed to confirm all authors’ conclusions.
Article
Full-text available
Background: Despite the existence of many clinical studies on platelet-rich plasma (PRP) interventions for ligamentous pathology, basic science consensus regarding the indications, mechanisms, and optimal composition of PRP for treating ligament injuries is lacking. Purpose: To (1) compare the efficacy of PRP in animal models of ligament injury with placebo and (2) describe the potential variability in PRP preparation using accepted classification systems. Study Design: Systematic review. Methods: The Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, PubMed, Embase, and Ovid MEDLINE were queried in April 2020 for in vivo and in vitro basic science studies regarding PRP use for ligament injury. Study design, results, PRP composition, and analyzed cellular and molecular markers were extracted, and outcomes relative to control models were documented. Bias was assessed using the SYRCLE risk-of-bias tool. Results: Included were 43 articles (31 in vivo and 12 in vitro studies) investigating the anterior cruciate ligament/cranial cruciate ligament (n = 32), medial collateral ligament (n = 6), suspensory ligament (n = 3), patellar ligament (n = 1), and Hock ligament (n = 1). Platelet concentration was reported in 34 studies (77.3%); leukocyte composition, in 12 (27.3%); and red blood cell counts, in 7 (15.9%). With PRP treatment, 5 of 12 in vitro studies demonstrated significant increases in cell viability, 6 of 12 in gene expression, 14 of 32 in vivo studies reported superior ligament repair via histological evaluation, and 13 in vivo studies reported superior mechanical properties. Variability in PRP preparation methods was observed across all articles, and only 1 study reported all necessary information to be classified by the 4 schemes we used to evaluate reporting. Among the in vivo studies, detection and performance bias were consistently high, whereas selection, attrition, reporting, and other biases were consistently low. Conclusion: Conflicting data on the cellular and molecular effects of PRP for ligament injuries were observed secondary to the finding that included studies were heterogeneous, limiting interpretation across studies and the ability to draw meaningful conclusions. Clinical trials and any causal relationship between PRP use in ligament injuries and its potential for regeneration and healing should be pursued with caution if based solely on basic science data.
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Background: Plasma concentrate products have Rapidly developed during the last few years, and it had significantly improved regenerative medicine because of its specific features which enhance healing and reduce pain after surgeries. this research aims to improve the antibacterial effectiveness of PRF by adding different forms of antibiotics and evaluate the physical and antibacterial properties of the new PRF. Methods: In-Vitro experimental study was conducted; modified protocol was used which use two stages of centrifuging was used prepare PRF. Bacterial colonies and Miller-Hinton medium was prepared. Two types of bacteria were used for the culturing and incubation (Staphylococcus aureus, Enterococcus faecalis). Different forms and volumes of antibacterial agents (Lincomycin) were incorporated with the PRF. Physical and antibacterial properties were evaluated. Results: ampoule and solution forms had the highest levels of bacterial growth inhibiting, and best physical properties, bacterial inhibiting lasted for 10 days in culture. Significant difference was noticed between the modified PRF and the control group (p<0.05). adding (0.5 ml) of ampoule form had the best results on both antibacterial and physical properties of the new PRF. Conclusion: The protocol proposed in this study succeeded to improve the antibacterial activity of the PRF with preserving the physical properties. No significant difference in physical properties were noticed between control group and PRF with antibiotic. Significance and impact of the study: PRF can be used as a local antibiotic delivering biomaterial adjacent to minor surgery, the results of this study can be used to reduce the post-operative infection that is frequent after oral surgeries.
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Use of platelet-rich plasma (PRP) has shown promise in various orthopaedic applications, including treatment of anterior cruciate ligament (ACL) injuries. However, various components of blood, including peripheral blood mononuclear cells (PBMCs), are removed in the process of making PRP. It is yet unknown whether these PBMCs have a positive or negative effect on fibroblast behavior. To begin to define the effect of PBMCs on ACL fibroblasts, ACL fibroblasts were cultured on three-dimensional collagen scaffolds for 14 days with and without PBMCs. ACL fibroblasts exposed to PBMCs showed increased type I and type III procollagen gene expression, collagen protein expression, and cell proliferation when the cells were cultured in the presence of platelets and plasma. However, addition of PBMCs to cells cultured without platelets had no effect. The increase in collagen gene and protein expression was accompanied by an increase in IL-6 expression by the PBMCs with exposure to the platelets. Our results suggest that the interaction between platelets and PBMCs leads to an IL-6 mediated increase in collagen expression by ACL fibroblasts. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
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Platelet-rich plasma (PRP) is a concentrate extract of platelets from autologous blood, and represents a possible treatment option for the stimulation and acceleration of soft-tissue healing and regeneration in orthopedics. Currently, the availability of devices for outpatient preparation and delivery contributes to the increase in the clinical use of PRP therapy in practical setting of orthopedic fields. However, there is still paucity of scientific evidence in the literature to prove efficacy of PRP therapy for the treatment of ligament or tendon problems around the knee joint. Moreover, strong evidence from well-designed clinical trials to support the PRP therapy for osteoarthritis of the knee joint is yet scanty in the literature. Scientific studies need to be performed to assess clinical indications, efficacy, and safety of PRP, and this will require high powered randomized controlled trials. Nonetheless, some hospitals exaggeratedly advertise PRP procedures as the ultimate treatment and a novel technology with abundant scientific evidence for the treatment of knee problems. As a matter of fact, PRP protocols are currently approved only for use in clinical trials and research, and are not allowed for treatment purpose by any institutions in Korea. At present, clinical use of PRP therapy for ligament or tendon problems or osteoarthritis of knee joint is defined as illegal medical practice, regardless of whether it is performed as a sole procedure or as a part of prolotherapy, because the safety and validity are not yet approved by the Ministry of Health and Welfare and Health Insurance Review and Assessment Service. Practicing physicians should remember that injection of PRP to patients by imposing medical charge is still illegal as per the current medical law in Korea.
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To compare the safety and efficacy of two different approaches of platelet-rich plasma (PRP) production methods as intra-articular injection treatment for knee cartilage degenerative lesions and osteoarthritis (OA). The study involved 144 symptomatic patients affected by cartilage degenerative lesions and OA. Seventy-two patients were treated with 3 injections of platelet concentrate prepared with a single-spinning procedure (PRGF), the other 72 with 3 injections of PRP obtained with a double-spinning approach. The patients were evaluated prospectively at the enrollment and at 2, 6, and 12 months' follow-up with IKDC, EQ-VAS and Tegner scores; adverse events and patient satisfaction were also recorded. Both treatment groups presented a statistically significant improvement in all the scores evaluated at all the follow-up times. Better results were achieved in both groups in younger patients with a lower degree of cartilage degeneration. The comparative analysis showed similar improvements with the two procedures: in particular, IKDC subjective evaluation increased from 45.0 ± 10.1 to 59.0 ± 16.2, 61.3 ± 16.3, and 61.6 ± 16.2 at 2, 6, and 12 months in the PRGF group, and from 42.1 ± 13.5 to 60.8 ± 16.6, 62.5 ± 19.9, and 59.9 ± 20.0 at 2, 6, and 12 months in the PRP group, respectively. Concerning adverse events, more swelling (P = 0.03) and pain reaction (P = 0.0005), were found after PRP injections. Although PRP injections produced more pain and swelling reaction with respect to that produced by PRGF, similar results were found at the follow-up times, with a significant clinical improvement with respect to the basal level. Better results were achieved in younger patients with a low degree of cartilage degeneration. II.
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Various types of platelet (PLT) products, such as Platelet Rich Plasma (PRP) and Platelet Gel (PG), derived from autologous peripheral blood, have been used for tissue repair. The good clinical outcomes, due mainly to their safety and Growth Factor (GF) content, have led to a wide use of PLT products in many fields of medicine. However, until now the existing literature adds controversies to the use of PLT concentrates. When talking about PLTs and their products, a great number of variables have to be considered. These variables are mainly related to PRP preparation methods, the type of activators, intra- and inter-species variability, types of pathology to be treated, the ways and times of administration and the association of PRP or PG with other treatments. This review considers and discusses these causes of variability with particular attention to orthopaedic implications. The possibility of improving the knowledge on variables affecting therapeutic efficacy will surely help in addressing the best combination of factors implied in the different steps of PLT concentrate preparation and use.
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Tissue repair in musculoskeletal lesions is often a slow and sometimes incomplete process. In sports patients or professional athletes, the impact of musculoskeletal lesions on life and work is great, and the fast recovery of full efficiency and return to competition is of primary importance. The clinical improvement offered by available treatments is not always sufficient for highly demanding patients to return to their previous level of activity. The search for a minimally invasive solution to improve the status of the chondral surface of the injured joint is therefore highly desirable, especially in these patients. Platelet-rich plasma (PRP) is a procedure that allows to obtain a natural concentration of autologous growth factors. The attractive possibility to use the patients' own growth factors to enhance reparative process in tissues with low healing potential, the promising preliminary clinical findings and the safety of these methods, explain the wide application of this biological approach. The aim of this review is to analyse the existing published studies to look for scientific evidence in preclinical studies or in the results obtained through PRP application in humans that supports the efficacy of PRP and its use for the treatment of tendinous, ligamentous, cartilaginous and muscular injuries. The analysis of the literature shows promising preclinical results but contradictory clinical findings for the treatment of sport injuries. High-quality studies are required to confirm these preliminary results and provide scientific evidence to support its use.
Article
Background: Platelet rich plasma has been promoted as a biologic agent to enhance tissue healing. As a concentration of autologous growth factors, it has gained increased use in musculoskeletal applications. Methods: The purpose of this study was to evaluate the effect of intra-operative PRP on patient-reported outcomes 2 years after ACL reconstruction with tibialis anterior allograft. Fifty patients who underwent allograft ACL reconstruction with intra-operative application of PRP to the graft were matched with 50 allograft ACL -reconstructions without PRP use. The same surgeon performed all procedures with identical technique. Two year patient-reported outcomes including KOOS, IKDC, and Marx activity scores were obtained. Effusions in the immediate post-operative period, post-operative complications, and any subsequent procedures were also recorded. Results: There was no difference between the groups with respect to additional surgeries or complications in the first 2 years after reconstruction. Decreased effusions at 10±4 days were noted in the PRP group, but this difference disappeared by 8±4 weeks. No differences in patient-reported outcomes were noted in the 58 patients with two-year outcome data. Conclusion: The study demonstrated that although PRP application in tibialis allograft ACL reconstructions appeared safe; clinical benefit was minor and short-term. No differences in patient-reported outcomes or number of additional surgeries at 2 years were noted. Level of evidence: Level III - retrospective comparative study.
Article
Cell migration plays an essential role in development, wound healing, and tissue regeneration. Plasma rich in growth factors (PRGF-Endoret) technology offers a potential source of growth factors involved in tissue regeneration. Here, we evaluate the potential of PRGF-Endoret over tendon cells and synovial fibroblasts migration and study whether the combination of this autologous technology with hyaluronic acid (HA) improves the effect and potential of the biomaterials over the motility of both types of fibroblasts. Migration of primary tendon cells and synovial fibroblasts after culturing with either PRGF or PPGF (plasma poor in growth factors) at different doses was evaluated. Furthermore, the migratory capacity induced by the combination of PPGF and PRGF with HA was tested. PPGF stimulated migration of both types of cells but this effect was significantly higher when PRGF was used. Tendon cells showed an increase of 212% in migratory ability when HA was combined with PPGF and of 335% in the case of HA + PRGF treatment compared with HA alone. PRGF-Endoret stimulates migration of tendon cells and synovial fibroblasts and improves the biological properties of HA.