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ABSTRACT: To investigate the effect of platelet-rich plasma (PRP) on TGF-beta1 expression during tendon healing.
We used 48 skeletally mature New Zealand White rabbits. 24 rabbits received the PRP, and 24 rabbits served as an untreated control group. Equal numbers of animals were sacrificed at 1st, 2nd, 3rd, and 4th week. The surgical procedure involved a transverse incision to transect the Achilles tendon. A volume of 1ml of PRP was then injected into the tendon mass in the PRP group. Histological and immunohistochemical evaluations with an anti-TGF-beta primary antibody were performed.
The pattern of expression of TGF-beta1 in the PRP group was characterized by a significant upregulation during the first 2 weeks and subsequently significant downregulation in the 3rd and 4th week in comparison with the controls.
Our results suggest that PRP may affect the tendon healing process by altering the expression of TGF-beta1.
Foot and Ankle Surgery 09/2010; 16(3):137-41.
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ABSTRACT: The aim of this study was to test the hypothesis that combined administration of TGF-b1 and IGF-I in a patellar tendon defect model could enhance the mechanical properties of the healed tendon. Twenty four New Zealand white rabbits were used for this purpose. In each animal, the right knee was used for the application of the growth factors, whereas the left knee served as an untreated control. The growth factors were mixed with fibrin sealant as a delivery vehicle. Two groups of rabbits were sacrificed after 2 weeks and 6 weeks respectively. Application of the growth factors resulted in a significant increase in force at failure, ultimate stress, stiffness, and energy uptake at 2 weeks, whereas none of the parameters revealed any significant difference between the two groups at 6 weeks. This study provides valuable information on the effect of the two growth factors on this patellar tendon defect model.
Acta orthopaedica Belgica 06/2010; 76(3):380-6. · 0.40 Impact Factor
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ABSTRACT: The aim of this study was to assess the hypothesis that application of platelet-rich plasma (PRP) gel in mandibular defects in rabbits, alone or in combination with guided bone regeneration (GBR) techniques, could enhance the bone healing process.
Thirty New Zealand white rabbits were used. Three groups of 10 animals each were assigned, and the animals were sacrificed after 12 weeks. During the operation, a rotating trephine bur was used to create circular defects 10-mm in diameter in the region anterior to the jaw angles. In group human fascia lata (HFL), a human fascia lata membrane was used. In group PRP, PRP gel was used to fill the defect, and in group HFL+PRP, PRP was used to fill the defect which after that was covered with a human fascia lata membrane.
In general, none of the control sides and the PRP treated sides had full development of bone or filling of the defect through bone bridging. Conversely, the sides on which the fascia lata membrane or the combination of membrane and PRP had been applied were characterized mostly by development of newly formed bone that bridged the gap.
Our results suggest that the application of PRP gel alone or in combination with GBR does not enhance bone healing process.
Journal of cranio-maxillo-facial surgery: official publication of the European Association for Cranio-Maxillo-Facial Surgery 04/2010; 39(1):49-53. · 1.25 Impact Factor
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ABSTRACT: The poor vascularity of tendons is a major factor in their limited healing capacity. The aim of this study was to assess the effect of Platelet Rich Plasma (PRP) on angiogenesis during tendon healing.
Forty-eight skeletally mature New Zealand White rabbits were used. The Achilles tendon was transected transversely and 0.5 ml of PRP was injected into the tendon mass on each side of the incision on both limbs. The injection in the control group consisted of saline. Six animals from each group (12 tendons each) were sacrificed after 1, 2, 3, and 4 weeks following treatment. Three sections from each Achilles were stained with hematoxylinosin for microscopic examination. Further three sections were immunostained with a monoclonal antibody against CD31 (Daco Co), followed by image analysis to count new vessel numbers and statistical analysis was performed.
There was significantly more angiogenesis in the PRP group compared to the control group during the first two weeks of the healing process, i.e., inflammatory and proliferative phase (p < 0.0001). The orientation of collagen fibers in the PRP group was better organized. The number of the newly formed vessels in the PRP group were significantly reduced at 4 weeks compared to the controls (p < 0.0001) suggesting the healing process was shortened.
PRP seems to enhance neovascularization which may accelerate the healing process and promote scar tissue of better histological quality.
Although these results need replication and further biomechanical research, PRP may promote tendon healing acceleration.
The Foot and Ankle Online Journal 11/2009; 30(11):1101-6. · 1.22 Impact Factor
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Dionysios Chissas,
George Stamatopoulos, Dionysios Verettas,
Konstantinos Kazakos,
Apostolos Papalois,
George Agrogiannis,
Athanasios Papaeliou,
Emmanouel Agapitos,
Alexia Balanika,
Eleftheria Papadopoulou,
George Anastopoulos,
Panagiotis G Ntagiopoulos,
Antonios Asimakopoulos
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ABSTRACT: Several observational and experimental studies have investigated the potential anabolic effects of statins on undisturbed bone but only a few recent studies have examined the effect of statins on skeletal repair. The goal of the study is to investigate any potential early anabolic effect of the systemic administration of simvastatin in low doses (based on earlier safety and efficacy studies on undisturbed bone) on fracture healing. Fifty-four skeletally mature male New Zealand White rabbits were used for the study. The rabbits were assigned to one of three experimental groups: a control group, and two groups that were orally administrated a diet with 10 and 30 mg/kg/day of simvastatin, respectively. A complete biochemical blood count was performed to exclude drug-induced complications. Half of the animals of each group were sacrificed at 15 days and the other half at 30 days after surgery at which time intervals healing quality was assessed. The bones were subjected to biomechanical testing, histomorphometric analysis and peripheral quantitative computed tomography. In animals received simvastatin of 30 mg/kg/day a significant reduction of BMD, stiffness, and energy absorbed to failure were observed. At 15 days, the amount of cartilaginous callus formation was reduced, and the void space was significantly increased, in the animals of both groups that received simvastatin when compared to the control group (p<.05). Our results suggest that simvastatin doses of 30 mg/kg/day may have a negative anabolic effect on callus formation in rabbits, whereas doses of 10 mg/kg/day seem not to produce a significant positive or a negative effect, especially at the early stages of fracture remodeling.
Injury 10/2009; 41(7):687-92. · 1.98 Impact Factor
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ABSTRACT: The aim of this study is to assess if an application of platelet-rich plasma (PRP) gel would improve the mechanical properties of rabbit's patellar tendon after resecting its central portion.
Forty skeletally mature New Zealand White rabbits were used. Two groups ten rabbits each (PRP and control group) were used to evaluate mechanical properties and histology after 14 days and two groups ten rabbits each (PRP and control groups) were used to evaluate mechanical properties and histology after 28 days.
At 14 days, PRP group showed a 72.2% increase in force at failure, a 39.1% increase in ultimate stress, and a 53.1% increase in stiffness, as compared with controls. These changes were statistically significant (P < 0.05). At 28 days, there was no longer any significant difference between PRP and control groups (P > 0.05).
In our study, the mechanical properties of the regenerated tendon in the PRP group were significantly improved in relation to the control group. It appears that PRP has a strong effect in the early phase of tendon healing. This effect is probably due to the growth factors that are released from the platelets during activation.
Archives of Orthopaedic and Trauma Surgery 08/2009; 129(11):1577-82. · 1.37 Impact Factor
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ABSTRACT: A full thickness defect was made in the central portion of the patellar tendon of 48 New Zealand white rabbits. Platelet-rich plasma (PRP) gel was then applied and filled the tendon defect. The same procedure was performed in the control group, without the application of PRP. Animals were sacrificed after one, two, three, and four weeks. Histological and immunohistochemical analyses using a monoclonal antibody against CD31 were performed. The histological examination showed a superior healing process in the PRP group compared with the control group. Especially in the third week, the tissue formed in the PRP group was more mature and dense with less elastic fibres remaining. Neovascularisation was significantly higher in the PRP group during the first two weeks and significantly lower in the third and fourth weeks (p < 0.0001). Histological examination and study of angiogenesis showed that the application of PRP enhances and accelerates the tendon healing process.
International Orthopaedics 03/2009; 34(1):143-8. · 2.03 Impact Factor
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ABSTRACT: Anterior dislocation of the shoulder joint with an ipsilateral fracture of the humeral shaft is a rare injury which may require demanding technical skills.
A 33 years old male sustained a work accident. Radiographs showed an anterior dislocation of the shoulder with a transverse fracture of the middle third of the humeral shaft on the same side. The dislocation proved to be irreducible in the setting of the fracture humerus. Thus, stabilization of the shaft fracture was successfully applied with an intramedullary nail and a small antirotational plate prior to the reduction. The patient recovered full function of the shoulder.
Performing primary intramedullary nailing of the humeral shaft fracture before manipulation of the joint resulted to an excellent outcome.
Cases Journal 01/2009; 2:9075.
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ABSTRACT: The outcome of total knee arthroplasty (TKA) after high tibial osteotomy (HTO) is still controversial. In order to determine if osteotomy has any effect on this outcome we performed a medium-term review of a cohort of patients with knee osteoarthritis.
Thirty-two patients (38 knees), who were treated with a HTO before the TKA during the last 8 years, were compared with a matched group who underwent primary TKA. The knees were evaluated preoperatively and postoperatively according to the scoring systems of the Knee Society and Hospital for Special Surgery (HSS). The anteroposterior tibiofemoral alignment, the Insall-Salvati patellar position ratio, range-of-motion and the location of the lateral joint line, were also recorded. The patients were reviewed with a mean follow-up of 4.5 years after TKA.
The preoperative and postoperative knee scores had no statistically significant differences between the two groups. So was the case with the intraoperative releases, blood loss, thromboembolic or neurologic complications and infection rates in either group. Access to perform the arthroplasty was reportedly more difficult and took an average of 25 min longer. A significant difference (p < 0.05) was detected in terms of impingement of the tibial stem on the lateral tibial cortex, patellar subluxation and patella baja between the two groups but this did not have any influence on the outcome of the prosthesis. Knee alignment and stability so as range of motion (ROM) measurements were also found with no statistical significance.
Although we did manage to detect statistically significant differences mainly in radiographic results between the two groups, this situation did not appear to influence the clinical outcome of the patients, however. The fact that most of the patients had good or excellent results at an average follow-up of 4.5 years suggests that HTO does not have a significant negative effect on later TKA.
Archives of Orthopaedic and Trauma Surgery 02/2008; 128(2):167-73. · 1.37 Impact Factor
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ABSTRACT: This study concerns 56 elderly high-risk patients with an intertrochanteric fracture of the femur, who were treated with the Citieffe/Ch-N external fixator between November 2002 and February 2004. A short intraoperative time (37 minutes), no need for peroperative blood transfusion, fast mobilisation and a short hospitalisation (average 6 days, thus reducing the total cost) were noted. Union was obtained in all patients after 6 months. There was no significant difference between the functional status before the injury and at follow-up after 12 months (p > 0.05). No deep pin track or wound infections occurred, but a superficial skin reaction was seen in 39.3%. The mortality rate was 16.1% at 6 months, and 20.4% at 12 months, which contrasts favourably with other types of treatment. External fixation with this device can be used successfully for the treatment of elderly high-risk patients with intertrochanteric fractures.
Acta orthopaedica Belgica 03/2007; 73(1):44-8. · 0.40 Impact Factor
