Objective To study the mechanism of compound of calcium phosphate(TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis.Methods The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make themodel of femoral head necrosis.Twenty-four rabbits were randomly chosen as theexperimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4,8,12 weeks after operation. The specimens were examined with X-ray and histological study.Results At 2 weeks after operation,there was no significant difference in femoral headdensity between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8,12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed thatthere was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4,8,12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greaterthan those in control group．Bone histomorphometry showed that the volum of thetrabecular was larger in the experimental group (36.65%±7.22%,38.29%±4.28%，39.24%±3.42%) than that of control group(P＜0.05). Conclusion TCP/PRP does not only provide osteoblasts scaffold, butalso promotes bone formation and the head repair. TCP/PRP is a good biomaterialfor the treatment of femur head necrosis.
ObjectiveTo explore the clinical efficacy of the ultrasound-guided intra-articular injection of platelet-rich plasma (PRP) in the treatment of patients with different stages of knee osteoarthritis.MethodsWe retrospectively analyzed the clinical characteristics and X-ray data of patients with knee osteoarthritis who received ultrasound-guided intra-articular injection of PRP in the Department of Rehabilitation Medicine at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University between May 2018 and June 2019. The patients were grouped according to the Kellgren & Lawrence Classification (K&L 0, Ⅰ, Ⅱ, Ⅲ, and Ⅳ). All the patients received four injections with a one-week interval. The Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used to evaluate the clinical efficacy before the injection, and 3 and 6 months after the injection. Adverse reactions were recorded.ResultsA total of 102 patients were included without any grade 0 cases. There were 20 patients in K&L Ⅰ group, 37 in Ⅱ group, 31 in Ⅲ group, and 14 in Ⅳ group. No adverse event was reported. Significant differences of VAS scores and WOMAC index were observed in Ⅰ, Ⅱ and Ⅲ groups at the 3rd and 6th month follow-up (P<0.05). VAS and WOMAC scores of the three groups at the 3rd and 6th month after the treatment were significantly improved compared with those before the treatment (P<0.05). There was no significant difference in VAS score at the 3rd or 6th month after the treatment three groups (P>0.05). For K&L Ⅰ group, there was no statistically significant difference in WOMAC score at the 3rd or 6th month after the treatment (P>0.05). However, the WOMAC scores at the 3rd month after the treatment were better than those at the 6th month in K&L Ⅱ and Ⅲ groups (P<0.05). There was no significant time-depended changes in VAS score or WOMAC score in K&L Ⅳ group (P>0.05).ConclusionThe ultrasound-guided intra-articular PRP injection is safe and effective for pain relief and function improvement in patients with knee osteoarthritis at the early and middle stage.
Objective To study the effect of platelet-rich plasma (PRP) on repairing chronic wounds of lower l imbs. Methods From May 2007 to November 2007, 47 patients suffering from chronic wounds of lower l imbs were treated. There were 41 males and 6 females, aged from 15 to 68 years (43.2 years on average). The disease was caused by tibiofibulafracture in 20 cases, calcaneus fracture in 4 cases, metatarsal fracture in 1 case, multiple open fracture of lower l imbs in 3 cases, tibia osteomyel itis in 10 cases, femur osteomyel itis in 1 case, soft tissue injury of ankle in 4 cases, infection after amputation in 2 cases, infection after foot orthomorphia in 1 case, and infection after calcaneus tendon neoplasty in 1 case. Their chronic wounds did not healed after 2 to 4 months of therapy. Among them, chronic wounds compl icated with fracture nonunion in 23 cases and positive bacterial culture result in 38 cases. Debridement and autogenous PRP gel injection were appl ied every 2 months and for twice. Results The patients were followed up for 4 months after the first PRP injection. Two months after the first PRP injection, chronic wounds contracted significantly in 34 patients with purulence and necrosis tissue cleaned up, circulation of soft tissue improved and exposed bone or muscle tissue covered by neogenetic granulation. No patient was completely cured. Two months after the second PRP injection, the average coverage rate was 79.3% ± 18.0%, the total cure rate was 29.8%. The volume of the chronic wounds decreased by (9.3 ± 4.9) mL after PRP therapy (2.5 ± 2.7) mL when compared with (11.8 ± 5.6) mL of before therapy, showing significant difference (P lt; 0.05). X-ray photograph showed that among the 23 cases of fracture nonunion, fracture healed completely in 9 cases; bony callus formation increased obviously in 12 cases; no significant change was observed in 2 cases. No aggravated sign of osteomyel itis was notified. Positive results of bacterial culture reduced to 15 cases. Conclusion PRP efficiently enhances the recovery of soft tissue defect and speeds up the chronic wounds heal ing oflower l imbs.
Objective Platelet-rich plasma (PRP) can promote wound heal ing. To observe the effect of PRP injection on the early heal ing of rat’s Achilles tendon rupture so as to provide the experimental basis for cl inical practice. Methods Forty-six Sprague Dawley rats were included in this experiment, female or male and weighing 190-240 g. PRP and platelet-poor plasma (PPP) were prepared from the heart arterial blood of 10 rats; other 36 rats were made the models of Achilles tendon rupture, and were randomly divided into 3 groups (control group, PPP group, and PRP group), 12 rats for each group. In PPP and PRP groups, PPP and PRP of 100 μL were injected around the tendons once a week, respectively; in the control group, nothing was injected. The tendon tissue sample was harvested at 1, 2, 3, and 4 weeks after operation for morphology, histology, and immunohistochemistry observations. The content of collagen type I fibers also was measured. Specimens of each group were obtained for biomechanical test at 4 weeks. Results All the animals survived till the end of the experiment. Tendon edema gradually decreased and sliding improved with time. The tendon adhesion increased steadily from 1 week to 3 weeks postoperatively, and it was relieved at 4 weeks in 3 groups. There was no significant ifference in the grading of tendon adhesion among 3 groups at 1 week and at 4 weeks (P gt; 0.05), respectively. The inflammatory cell infiltration, angiogenesis, and collagen fibers were more in PRP group than in PPP group and control group at 1 week; with time, inflammatory cell infiltration and angiogenesis gradually decreased. Positive staining of collagen type I fibers was observed at 1-4 weeks postoperatively in 3 groups. The positive density of collagen type I fibers in group PRP was significantly higher than that in control group and PPP group at 1, 2, and 3 weeks (P lt; 0.05), but no significant difference was found among 3 groups at 4 weeks (P gt; 0.05). The biomechanical tests showed that there was no significant difference in the maximal gl iding excursion among 3 groups at 4 weeks postoperatively (P gt; 0.05); the elasticity modulus and the ultimate tensile strength of PRP group were significantly higher than those of control group and PPP group at 4 weeks (P lt; 0.05). Conclusion PRP injection can improve the healing of Achilles tendon in early repair of rat’s Achilles tendon rupture.
Objective Platelet-rich plasma (PRP) contains high concentrations of platelets and leucocytes, which play a key role in antimicrobial host defense system. To evaluate the antimicrobial efficacy of autologous PRP in vitro and in vivo and to explore the mechanism of action so as to provide the experimental basis for the prevention and treatment of bone infection. Methods PRP was prepared with the method of two centrifugation from 15 health volunteers. Platelet-leukocytegel (PLG) was obtained after activation of PRP with bovine thrombin. Next, PLG was incubated with Staphylococcus aureus (1 × 106 cfu/mL) in vitro compared with PRP, platelet-poor plasma (PPP) and PBS. Samples were taken out after 2, 4, 6, 8, 12, and 24 hours for bacterial culture and colony count. Thirty-six New Zealand adult rabbits, weighing (2.85 ± 0.11) kg, were divided into 4 groups: PLG (n=10), antibiotic (n=10), infection (n=10), and PBS (n=6) groups. The osteomyel itis models were made by injecting 0.1 mL Staphylococcus aureus suspension (1 × 106 cfu/mL) into the tibial canal in PLG group, antibiotic group, and infection group; equal volumes of PBS was injected in PBS group as a control. Autologous PLG was injected immediately after operation in PLG group. Cefazol in (30 mg/kg) was injected through the auricular vein from 1 hour before operation to 72 hours after operation in antibiotic group, once per 8 hours. No treatment was given in infection and PBS groups. The efficacy of PLG for osteomyel itis prophylaxis was evaluated by microbiological, X-ray and histological observation within 28 days. Results The contents of leucocyte and platelet of PRP were 6.2 times and 5.5 times of whole blood, showing signficant differences ((P lt; 0.05); the contents of leucocyte and platelet of PPP were significantly lower than those of whole blood and PRP ((P lt; 0.05). In vitro test showed that PLG had the most obvious bacteriostasis effect. The bacterial count reached a minimum value at 4 hours after incubation in PLG and at 6 hours after incubation in PRP. PPP had slow and no obvious bacteriostasis effect and PBS had no bacteriostasis effect. At 2, 4, 6, 8, 12, and 24 hours of incubation, the bacterial count reduced significantly when compared PLG with PRP and PPP (P lt; 0.05), when compared PRP with PPP (P lt; 0.05). In PLG group and antibiotic group, 1 rabbit died, respectively; 34 rabbits survived to the end of the experiment. There was no significant difference (P gt; 0.05) in temperature, body weight, erythrocyte sedimentation rate and content of leucocyte between 28 days after operation andbefore operation in 4 groups. After 28 days, the X-ray scores were 2.78 ± 1.39, 1.55 ± 1.48, 4.17 ± 1.25, and 0 in PLG, antibiotic,infection, and PBS groups, respectively, which was significantly higher in infection group than in other 3 groups ((P lt; 0.05). Also, the histological scores were 5.89 ± 3.92, 3.00 ± 2.31, 10.33 ± 4.03, and 0, respectively, which was significantly higher in infection group than in other 3 groups (P lt; 0.05), and was significantly lower in antibiotic group than in PLG group ((P lt; 0.05). The results of bacterial culture showed that the infection rates of PLG group (44.4%) and antibiotic group (20.0%) were significantly lower ((P lt; 0.05) than that of infection group (88.9%). The quantitative analysis of bacteria showed that the number of bacteria was signifcantly lower ((P lt; 0.05) in PLG and antibiotic groups than in infection group. Conclusion PRP forms into PLG after activating, it can inhibit Staphylococcus aureus reproduction in vitro and can effectively prevent bone infection in vivo.
Objective
To investigate the interleukin-17 (IL-17) levels changes in both synovial fluid and venous plasma of patients with primary knee osteoarthritis (OA) after intra-articular injection of platelet-rich plasma (PRP).
Methods
Between January 2015 and January 2016, 30 patients with primary knee OA were treated by intra-articular injection of PRP once a week for 3 weeks (trial group). Thirty healthy individuals were recruited into the study as control. There was no significant difference in gender, age, and body mass index between 2 groups (P>0.05). Visual analogue scale (VAS) score and Knee Society Score (KSS) were used to evaluate pain level and function of the knee for patients with OA. The IL-17 levels in both venous plasma and synovial fluid were measured before injection and at 1, 3, 6, and 12 months after injection in trial group and the IL-17 levels in venous plasma were measured in control group. The levels were determined using ELISA method.
Results
There was no knee joint swelling, fever, local infection, or other uncomfortable symptoms for all patients in process of PRP injection. All patients were followed up 13.5 months on average (range, 12-15 months). In trial group, the VAS scores at different time points after injection were significantly lower than that before injection (P<0.05). And the KSS scores at different time points after injection were significantly higher than that before injection (P<0.05). There was no significant difference in VAS and KSS scores between different time points after injection (P>0.05). The IL-17 levels in venous plasma before and after injection in trial group were significantly higher than that in control group (P<0.05). The IL-17 levels in venous plasma at each time point after injection were significantly lower than that before injection (P<0.05). There was no significant difference in IL-17 levels in both venous plasma and synovial fluid between different time points after injection (P>0.05).
Conclusion
Intra-articular injection of PRP can significantly release the pain symptoms, improve joint function, and reduce IL-17 levels in both synovial fluid and venous plasma of the patients with knee OA, but IL-17 levels can not reduce to normal level.
Objective Platelet-rich plasma (PRP) can enhance the chondrocyte prol iferation and repair of cartilage defects. To explore the safety and efficacy of intra-knee-articular injection of PRP to treat knee articular cartilage degeneration by comparing with injecting sodium hyaluronate (SH). Methods Thirty consecutive patients (30 knees) with knee articular cartilage degeneration were selected between January 2010 and June 2010. According to different injections, 30 patients wererandomly divided into PRP group (test group, n=15) and SH group (control group, n=15). There was no significant difference in gender, age, body mass index, and Kellgren-Lawrence grade between 2 groups (P gt; 0.05). Test group received 3.5 mL of PRP intra-knee-articular injections while control group received 2 mL of SH during the same time period. Both treatments were administered in series of 3 intra-knee-articular injections at 3-week intervals. Then, adverse reactions were recorded. International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and Lequesne index were used for evaluation of treatment results. Results The patients of 2 groups were followed up 6 months. There were significant differences in IKDC score, WOMAC score, and Lequesne index between pre- and post-injection in 2 groups (P lt; 0.05); no significant difference was found between different time points (3, 4, and 6 months) in test group (P gt; 0.05), while significant differences were found between the postoperative 6th month and the postoperative 3rd and 4th months in control group (P lt; 0.05). There was no significant difference in IKDC score, WOMAC score, and Lequesne index between 2 groups within 4 months (P gt; 0.05), but the effectiveness of test group was significantly better than that of control group at 6 months after injection (P lt; 0.05). Adverse reactions occurred in 12 patients (31 injections) of test group and in 12 patients (30 injections) of control group. No significant difference in onset time, termination time, and duration of adverse reactions were found between 2 groups (P gt; 0.05). Conclusion Intra-knee-articular injection of PRP to treat knee articular cartilage degeneration is safe, which can alleviate symptoms of pain and swell ing and improve the qual ity of l ife of patients; however, further data of large samples and long-term follow-up are needed to confirm the safety and effectiveness.
Objective To explore the effect of platelet-rich plasma (PRP) in treatment of Achilles tendinopathy in rabbits, and provide experimental evidence for the clinical application of PRP in treatment of Achilles tendinopathy. Methods Forty-eight adult New Zealand white rabbits, weighing 2.5-3.0 kg, male or female, were randomly divided into model group (group A), model control group (group B), model+treatment control group (group C), model+treatment group (group D), with 12 in each group. The rabbits were injected with type Ⅰ collagenase to prepare Achilles tendinopathy models in groups A, C, and D, and with an equal dose of normal saline in group B. The blood from the central artery of rabbit ear was taken to preprare PRP by secondary centrifugation in group D. The results of platelet counts showed that PRP platelets reached 3 to 5 times the whole blood. After the model was prepared, the rabbits in groups C and D were injected with physiological saline and autologous PRP at the molding site respectively, once a week, 0.8 mL each time for 4 weeks. At 1 week after PRP injection, the relative hardness (expressed as HRD%) of Achilles tendon was evaluated by ultrasound elastic quantitative imaging detection technique; the maximum breaking load of Achilles tendon was measured by universal electronic tensile testing machine; the contents of collagen type Ⅰ and Ⅲ were determined by ELISA; and the morphology of Achilles tendon collagen fibers was observed by HE and Masson stainings. Results All animals survived during the experiment. The results of ultrasound elastic quantitative imaging and mechanical tests showed that the HRD% and the maximum breaking load were significantly lower in group A than in group B (P<0.05) and in group C than in group D (P<0.05). The results of ELISA showed that the content of collagen type Ⅰ was significantly lower in group A than in group B (P<0.05) and in group C than in group D (P<0.05); the content of collagen type Ⅲ was significantly higher in group A than in group B (P<0.05) and in group D than in group C (P<0.05). HE and Masson stainings showed that the Achilles tendon collagen fibers were irregularly curled and the structure was severely damaged in group A; the fibers were parallel and ordered, and the structure was complete in group B; the fibers were irregularly curled and structurally disordered in group C; the fibers were slightly curled and the structure was relatively complete in group D. Conclusion A rabbit model of Achilles tendinopathy can be reconstructed by type Ⅰ collagenase injection. PRP treatment can increase the Achilles tendon hardness and maximum breaking load, up-regulate the expression level of collagen type Ⅰ and Ⅲ, improve the structure of Achilles tendon collagen fiber, and promote the repair in rabbit Achilles tendinopathy model.
Objective To investigate whether combining use of platelet-rich plasma (PRP) and decalcified bone matrix (DBM) has synergistic action on promoting bone consol idation and heal ing. Methods Forty male New Zealand rabbits (weighing 2.2-2.8 kg) were randomly divided into 4 groups (n=10). The whole blood was extracted from the central aural artery and PRP was prepared with the Landesberg’s method. An 1 cm-defect was made below the tibiofibular joint of the lefttibia through osteotomy. In group A, defect was repaired by distraction osteogenesis (1 cm); in group B, defect was repaired with 0.5 cm DBM and then by distraction osteogenesis (0.5 cm); in group C, defect was repaired by distraction osteogenesis (1 cm) and local injection of 1 mL PRP; in group D, defect was repaired by 0.5 cm DBM combined with 1 mL PRP and then by distraction osteogenesis (0.5 cm). Then lengthening started at 7 days after operation, at a rate of 1 mm/day and 0.5 mm every time for 10 days (groups A and C) or for 5 days (groups B and D). After the lengthening, the consolidation was performed. The X-ray films were taken at 0, 12, 17, 27, and 37 days after operation. At 37 days after operation, the tibial specimens were harvested for Micro-CT scanning, three-dimensional reconstruction and biomechanical test. Results The X-ray films showed that new bone formation in groups B and C was obviously better than that in groups A and D at 37 days. The bone mineral density (BMD), bone mineral content (BMC), and bone volume fraction (BVF) of groups B and C were significantly higher than those of groups A and D (P lt; 0.05); the BMD and BMC of group C were significantly higher than those of group B (P lt; 0.05); the BVF had no significant difference between groups B and C (P gt; 0.05). There was no significant difference in BMD, BMC, and BVF between groups A and D (P gt; 0.05). The trabecula number (Tb.N) of group C was significantly more than that of other groups (P lt; 0.05), and the trabecula spacing (Tb.Sp) of group C was significantly smaller than that of other groups (P lt; 0.05), but no significant differencewas found among other groups (P gt; 0.05). There was no significant difference in the trabecula thickness among 4 groups (P gt; 0.05). The ultimate angular displacement had no significant difference among 4 groups (P gt; 0.05). The maximum torque of groups B and C was significantly higher than that of groups A and D (P lt; 0.05); the maximum torque of group C was significantly higher than that of group B (P lt; 0.05); no significant difference was found between groups A and D (P gt; 0.05). Conclusion In the rabbit bone defect/lengthening model, local injection of PRP can enhance bone consol idation effectively during consol idation phase. In normal distraction rate, DBM can promote bone consol idation during distraction osteogenesis. In the early stage of distraction osteogenesis, combining use of DBM and PRP can not further promote bone consolidation and healing.
Objective To investigate the factors that affect platelet-rich plasma (PRP) in promoting bone regeneration and repairing. Methods Recent l iterature was reviewed, concerning the preparations of PRP, physiological mechanism and the latest appl ications in orthopedic field. Results PRP, the concentrated body of autologous platelet, was rich in platelets and was the source of autologous growth factors. Many studies had shown that PRP played an important role in promoting bone regeneration and repairing. However, a few experimental results contradicted this point. The reason might be that the biological properties of PRP were influenced by various factors, such as workmanship, vector, activation schemes, working concentration, individual difference. Conclusion The concentration and qual ity of platelet and other related factorsof PRP affect the rel iabil ity of the results and conclusions. So an efficient and stable production method of PRP should beestabl ished.
