Systematic review of the efficacy of fat grafting and platelet-rich plasma for wound healing

Methacrylated gelatin and platelet-rich plasma based hydrogels promote regeneration of critical-sized bone defects

Physiological repair of large-sized bone defects requires instructive scaffolds with appropriate mechanical properties, biocompatibility, biodegradability, vasculogenic ability and osteo-inductivity. The objective of this study was to fabricate in situ injectable hydrogels using platelet-rich plasma (PRP)-loaded gelatin methacrylate (GM) and employ them for the regeneration of large-sized bone defects. We performed various biological assays as well as assessed the mechanical properties of GM@PRP hydrogels alongside evaluating the release kinetics of growth factors (GFs) from hydrogels. The GM@PRP hydrogels manifested sufficient mechanical properties to support the filling of the tissue defects. For biofunction assay, the GM@PRP hydrogels significantly improved cell migration and angiogenesis. Especially, transcriptome RNA sequencing of human umbilical vein endothelial cells and bone marrow-derived stem cells were performed to delineate vascularization and biomineralization abilities of GM@PRP hydrogels. The GM@PRP hydrogels were subcutaneously implanted in rats for up to 4 weeks for preliminary biocompatibility followed by their transplantation into a tibial defect model for up to 8 weeks in rats. Tibial defects treated with GM@PRP hydrogels manifested significant bone regeneration as well as angiogenesis, biomineralization, and collagen deposition. Based on the biocompatibility and biological function of GM@PRP hydrogels, a new strategy is provided for the regenerative repair of large-size bone defects.

Two-flap technique with interpositional dermofat graft for anterior oronasal fistula closure in patients with cleft: A case series

BACKGROUND

Oronasal fistula at the anterior hard palate is one of the common sequelae after cleft surgery, and the leakage negatively affects the patient's quality of life. Although several surgical techniques have been proposed for reconstruction, it remains challenging because of the scarred regional tissue with a high rate of fistula recurrence. In this study, we present the anterior oronasal fistula repair using a two-flap technique with an interpositional dermofat graft (DFG).

METHODS

A retrospective review of anterior oronasal fistula repair performed by the senior author between April 2018 and August 2022 at the Craniofacial Center was conducted. Patients who underwent a fistula repair using the technique were further identified and investigated.

RESULTS

Thirty-four operations were performed using the technique, and 31 fistulas were completely closed, with a success rate of 91.2%. The fistula symptom improved but persisted postoperatively in 3 patients, of whom 2 patients underwent a second fistula repair using the same procedure, resulting in successful closure. Fistula recurrence was significantly correlated with fistula size (p = 0.04). The DFG was simultaneously utilized for nasal dorsum and/or vermillion reconstruction in 28 cases.

CONCLUSION

The two-flap technique enabled tension-free approximation, and the interpositional DFG facilitated watertight closure of the fistula, resulting in a high success rate of anterior oronasal fistula repair. The fistula closure could be combined with other revisional procedures for cleft-related deformities, where the DFG was simultaneously utilized.

Free dermofat grafting for chest deformity in microtia reconstruction

OBJECTIVE

Chest deformity is one of the complications that occurs after costal cartilage harvesting for auricle reconstruction. In this study, we presented a novel method of free dermofat grafting to repair cartilage defect and aimed to evaluate its effect in ameliorating chest deformity.

METHODS

Seventy-six pediatric patients were included in the study, comprising free dermofat grafting group (n = 38) and control group (n = 38). After harvesting costal cartilage, empty perichondrial space of right seventh costal cartilage was filled with free dermofat grafts in free dermofat grafting group. Thoracic computed tomography (CT) was performed three months after surgery and 3D colormap quantification was performed to quantify chest surface asymmetry. The quantified data were further analyzed to compare chest asymmetry level in free dermofat grafting and control groups.

RESULTS

In the free dermofat grafting group, the mean of asymmetry level was 2.2 mm. While in the control group, the mean of asymmetry was 5.7 mm. After a comparison between the two groups, the level of asymmetry showed a significant difference (p < 0.01).

CONCLUSION

Free dermofat grafting method is easy to perform and a feasible option for ameliorating chest deformity in microtia reconstruction.

An Injectable Integration of Autologous Bioactive Concentrated Growth Factor and Gelatin Methacrylate Hydrogel with Efficient Growth Factor Release and 3D Spatial Structure for Accelerated Wound Healing

Growth factors are essential for wound healing owing to their multiple reparative effects. Concentrated growth factor (CGF) is a third-generation platelet extract containing various endogenous growth factors. Here, a CGF extract solution is combined with gelatin methacrylate (GM) by physical blending to produce GM@CGF hydrogels for wound repair. The GM@CGF hydrogels show no immune rejection during autologous transplantation. Compared to CGF, GM@CGF hydrogels not only exhibit excellent plasticity and adhesivity but also prevent rapid release and degradation of growth factors. The GM@CGF hydrogels display good injectability, self-healing, swelling, and degradability along with outstanding cytocompatibility, angiogenic functions, chemotactic functions, and cell migration-promoting capabilities in vitro. The GM@CGF hydrogel can release various effective molecules to rapidly initiate wound repair, stimulate the expressions of type I collagen, transform growth factor β1, epidermal growth factor, and vascular endothelial growth factor, promote the production of granulation tissues, vascular regeneration and reconstruction, collagen deposition, and epidermal cell migration, as well as prevent excessive scar formation. In conclusion, the injectable GM@CGF hydrogel can release various growth factors and provide a 3D spatial structure to accelerate wound repair, thereby providing a foundation for the clinical application and translation of CGF.

Comparison of the Effect of MFAT and MFAT + PRP on Treatment of Hip Osteoarthritis: An Observational, Intention-to-Treat Study at One Year

Hip osteoarthritis (OA) is a major contributor to reduced quality of life and concomitant disability associated with lost working life months. Intra-articular injection of various biological materials has shown promise in alleviating symptoms and potentially slowing down the degenerative process. Here, we compared the effects of treatment of a cohort of 147 patients suffering from grade 1–4 hip OA; with either micro-fragmented adipose tissue (MFAT), or a combination of MFAT with platelet-rich plasma (PRP). We found significant improvements in both the visual analogue score for pain (VAS) and Oxford hip score (OHS) that were similar for both treatments with over 60% having an improvement in the VAS score of 20 points or more. These results suggest a positive role for intra-articular injection of MFAT + PRP as a treatment for hip osteoarthritis which may be important particularly in low body mass index (BMI) patients where the difficulty in obtaining sufficient MFAT for treatment could be offset by using this combination of biologicals.

Modern Wound Dressings: Hydrogel Dressings

Chronic wounds do not progress through the wound healing process in a timely manner and are considered a burden for healthcare system; they are also the most common reason for decrease in patient quality of life. Traditional wound dressings e.g., bandages and gauzes, although highly absorbent and effective for dry to mild, exudating wounds, require regular application, which therefore can cause pain upon dressing change. In addition, they have poor adhesional properties and cannot provide enough drainage for the wound. In this regard, the normalization of the healing process in chronic wounds is an extremely urgent task of public health and requires the creation and implementation of affordable dressings for patients with chronic wounds. Modern wound dressings (WDs) are aimed to solve these issues. At the same time, hydrogels, unlike other types of modern WDs (foam, films, hydrocolloids), have positive degradation properties that makes them the perfect choice in applications where a targeted delivery of bioactive substances to the wound is required. This mini review is focused on different types of traditional and modern WDs with an emphasis on hydrogels. Advantages and disadvantages of traditional and modern WDs as well as their applicability to different chronic wounds are elucidated. Furthermore, an effectiveness comparison between hydrogel WDs and the some of the frequently used biotechnologies in the field of regenerative medicine (adipose-derived mesenchymal stem cells (ADMSCs), mesenchymal stem cells, conditioned media, platelet-rich plasma (PRP)) is provided.

Using Dermofat Grafting in Revision Rhinoplasty

BACKGROUND

For revision surgeries due to complications associated with alloplastic materials, autologous tissues including dermofat are considered. However, graft absorption, shaping, and donor site morbidity remain crucial challenges. This study aimed to present several surgical techniques of dermofat grafting for rhinoplasty to overcome these challenges.

METHODS

Patients who underwent autologous dermofat grafting from January 2015 to October 2019 were retrospectively studied, and those who underwent primary rhinoplasty were excluded. The mid-sacral dermis (with the thickest dermal layer) was selected as the main donor site. During dermal harvesting, fat was resected into a wedge shape, to minimize flap tension and dead space risk. A molding technique was applied to improve graft shape and height and minimize graft absorption. Patient records were reviewed for assessing preoperative evaluations, surgical methods, and complications. For evaluating aesthetic outcomes, three rhinoplasty surgeons, blinded to the study purpose, compared preoperative and postoperative photographs.

RESULTS

Among 331 cases undergoing dermofat grafting for revision rhinoplasty, 25 underwent revisions; of these, five, one, and nine cases experienced over-absorption, over-correction, and deviation, respectively. One and eight cases underwent revision due to a widening scar at the dermofat donor site and wound dehiscence, respectively. Notably, one case had inflamed sinus formation.

CONCLUSIONS

The advanced dermofat graft technique provided favorable results with selection of appropriate donor site and a dermofat graft with subdermal fat. The application of this molding technique and proper management of donor site ameliorated critical disadvantages, thereby providing a safe and effective alternative for revision rhinoplasty.

EBM LEVEL IV

Rhinoplasty.

Optimization of the Soft Tissue Envelope of the Nose in Rhinoplasty Utilizing Fat Transfer Combined with Platelet-Rich Fibrin

A thin or damaged skin soft tissue envelope may cause concerns in primary and secondary rhinoplasty. During postoperative healing, unpredictable scarring and contraction may occur and lead to significant aesthetic and trophic sequelae. Besides a meticulous surgical technique, there are no reliable techniques to prevent long-term skin damage and shrinkage. Fat transfer with addition of platelet-rich fibrin (PRF) harbors the possibility of local soft tissue regeneration and skin rejuvenation through growth factors and mesenchymal stem cells. It may also facilitate the creation of a thin fat layer on the dorsum to prevent shrink-wrap forces and conceal small irregularities. The goal is to provide evidence for the feasibility, durability, and beneficial effect of diced macrofat transfer bonded with PRF on the nasal dorsum. We present the technique of fat transfer conjugated with PRF as a nasal dorsal graft. Clinical endpoints were the prevention of trophic disturbances and atrophy at a 1-year postoperative follow-up. We present the skin mobility test as a clinical indicator of a healthy soft tissue envelope. The presented case series consists of 107 rhinoplasties. Fat was harvested in the umbilical or costal region. PRF was created by centrifugation of autologous whole blood samples. Macrofat was diced, cleaned, and bonded with PRF. The compound transplants were transferred to the nasal dorsum. There were no perioperative complications or wound-healing issues. Mean follow-up was 14 months. Clinical inspection showed good skin quality and no signs of shrinkage, marked scarring, or color changes with positive skin mobility test in all patients. Survival of fat was confirmed by ultrasonography and magnetic resonance imaging. Diced macrofat transfer in conjunction with PRF to the nasal dorsum is a feasible and safe method. A beneficial effect on the soft tissue envelope is demonstrated as well as the prevention of shrink-wrap forces.

Comparison of the Effects of Repeated Applications of Platelet-Rich Plasma versus Platelet-Poor Plasma on Fat Graft Survival in Nude Mice

Autologous fat grafting has been widely used for soft tissue filling in plastic surgery. Platelet-rich plasma (PRP) could play a wide role in health and disease because of containing a variety of growth factors and cytokines. Although previous studies have described the positive effect of autologous PRP mixed with fat grafts, only minimal improvements in fat graft survival have been reported. The present study is aimed at comparing the effects of PRP and platelet-poor plasma (PPP) on the survival and quality of fat grafting. We built a 180-day nude mouse model implanted with a fat graft supplemented with PRP, PPP, or saline, respectively. The above reagents (PRP, PPP, or saline) were injected two additional times after the initial engraftment. The survival ratio of the fat grafts and the capillary density in the PRP group were significantly higher than those in the PPP group and the saline group (control group) at 15, 30, 90, and 180 days posttransplantation (P < 0.05). The survival ratio of the PPP group was higher than that of the saline group (P < 0.05), but the capillary density in the PPP group was not significantly different from that in the saline group at any time point (P > 0.05). We hence conclude that the repeated application of PRP or PPP three times can enhance the survival of fat grafts within 180 days. Moreover, the effect of PRP is superior to that of PPP.

Fat grafting and platelet-rich plasma for the treatment of diabetic foot ulcers: A feasibility-randomised controlled trial

Chronic, nonhealing diabetic foot ulcers (DFU) are increasing in prevalence and are often unresponsive to conventional therapy. Adipose tissue, containing adipose-derived stem cells, and platelet rich plasma (PRP) are regenerative therapies rich in growth factors which may provide a solution to chronic wound healing. This study aimed to assess the feasibility of conducting a definitive randomised controlled trial (RCT) to investigate the efficacy of these therapies for the treatment of DFU. This was a single centre, feasibility, three-arm, parallel group RCT. Eligible DFU patients were randomised on a 1:1:1 basis to three intervention arms: control (podiatry); fat grafting; fat grafting with PRP. The intervention was delivered once and patients were followed-up for 12 weeks. The primary objective was to assess measures of trial feasibility. Clinical outcomes and health-related quality of life (HRQoL) were also evaluated. Three hundred and thirty four patients were screened and 32 patients (9.6%) were deemed eligible with 18 enrolled in the trial (6 per arm) over 17 months. All participants completed the trial with no withdrawals or crossover. Participant engagement was high with most HRQoL questionnaires returned and only 4.8% follow-up appointments missed. There were five adverse events (AEs) related to the trial with no serious AEs. Five (28%) of the wounds healed. There was no difference between any of the groups in terms of clinical outcomes. This feasibility study demonstrated that a multi-centre RCT is safe and feasible with excellent patient engagement. We have highlighted crucial information regarding methodology and recruitment, which will guide future trial design. Registration number: NCT03085550 clinicaltrials.gov. Registered 01/03/2017.

Delayed two steps PRP injection strategy for the improvement of fat graft survival with superior angiogenesis

Platelet-rich plasma (PRP) has been widely used to improve the fat retention rate in autologous fat transplantation since it possesses a good angiogenesis capability in vivo. However, due to the short half-life of growth factors released from PRP and its uneven distribution in injected fat tissue, the strategy of PRP in fat transplantation needs further improvement. Since the capillaries started to grow into fat grafts in 1 week and vascular growth peaks in the second week after transplantation, we hypothesized that delayed two-steps PRP injection into the interior of grafts, accompanied with the extent of neovascularization might theoretically promote microvessel growth inside transplanted adipose tissue. 24 nude mice were divided into three groups: Blank group (0.35 mL fat mixed with 0.15 mL saline, N = 8), Single step group (0.35 mL fat mixed with 0.15 mLPRP, N = 8), and Two steps group (0.35 mL fat (day 0) + 0.075 mL PRP (day 7) + 0.075 mL PRP (day 14), N = 8). At 6 and 14 weeks post-transplantation, grafts were dissected, weighted, and assessed for histology, angiogenesis, fat regeneration and inflammation level. The weight and volume of the fat samples revealed no statistical difference among the three groups at 6 weeks after fat transplantation. The weight and volume of the Two steps group fat samples showed significantly higher compared to that in Blank and Single step groups at 14 weeks after fat transplantation (weight: 137.25 ± 5.60 mg versus 87.5 ± 3.90 mg,106.75 ± 2.94 mg, respectively; volume: 0.13 ± 0.01 mL versus 0.08 ± 0.01 mL, 0.09 ± 0.01 mL, respectively). Histological assessments indicated that delayed two-steps PRP injection strategy helps to improve adipose tissue content and reduce the composition of fibrous connective tissue at 14 weeks after fat transplantation. At 6 weeks and 14 weeks after transplantation, CD31 immunofluorescence indicated that delayed two-steps PRP injection strategy helps to improve angiogenesis and significantly higher compared to that in Blank and Single step groups (6 weeks: 28.75 ± 4.54 versus 10.50 ± 2.06, 21.75 ± 1.85; 14 weeks: 21.75 ± 2.86 versus 9.87 ± 2.08, 11.75 ± 1.47, respectively). Preadipocyte count indicated delayed two-steps PRP injection strategy might promote fat regeneration and significantly higher compared to that in Blank and Single step groups at 14 weeks (129.75 ± 6.57 versus 13.50 ± 3.50, 17.12 ± 6.23, respectively). In this study, we demonstrated that the novel delayed two-steps PRP injection strategy remarkably enhanced the long-term fat retention rate and improved the neovascularization extent in the interior of the fat graft. Platelet-rich plasma, Delayed two-steps injection, Angiogenesis, Fat transplantation.

Investigating the effect of age on platelet ultrastructure using transmission electron microscopy

In the present study, the age- and sex-related differences in platelet ultrastructure were investigated using transmission electron microscopy (TEM). A total of 15 healthy volunteers were grouped according to age, with 5 people in each of the following groups: young group (25-45 years), middle-aged group (46-65 years), and old-aged group (> 65 years). In the TEM micrographs, the internal components, specifically the α-granules, dense granules, and lysosomal granules, of 20 platelets were counted for each group. Two-way analysis of variance of age and sex variance was used to compare the results. The ultrastructure of the platelets in the old-aged group was observed to be quite different from those of the young and middle-aged groups. Specifically, with ageing, the platelet membrane becomes more irregular in shape and non-smooth, and multiple platelet membrane ruptures are observed. Furthermore, the pseudopodia and protuberances become more numerous and slender, and the number of α-granules is significantly reduced. These morphological changes indicate that ageing may affect the function of platelets, which in turn affects the efficacy of platelet concentrates. Thus, the effects of age should be considered when using platelet concentrates prepared from elderly autologous blood.

Iatrogenic wounds: a common but often overlooked problem

Iatrogenic wounds are a common but often overlooked concept. They can lead to increases in hospital stays, therapy costs, repeat surgeries, and implant removal. If not handled properly, these wounds have a very poor prognosis and will cause serious physical and psychological harm to patients, which may result in medicolegal disputes. In recent years, the incidence of iatrogenic wounds has increased because of (1) an increase in the population of older people owing to increased life expectancy, (2) the continued expansion of surgical indications, (3) an increase in difficult surgeries, and (4) the constant emergence and application of new implantable biomaterials and other therapies. Thus, there is a pressing clinical need to improve the therapy of iatrogenic wounds. However, the difficulty in treating these wounds is considerable due to the emergence of drug-resistant bacteria, the high number of patients with metabolic diseases, and complex complications in patients. In particular, iatrogenic wounds caused by surgical site infections due to implantable biomaterials could lead to material leakage and conflicts regarding whether to retain or remove the implants. This review provides a definition of iatrogenic wounds, describes their characteristics, classifies them, and provides information about the importance of analyzing iatrogenic wounds. We hope that this review will provide useful information for the diagnosis and treatment of iatrogenic wounds and help to reduce their incidence in the future.

Allergic reaction to platelet-rich plasma (PRP): Case report

RATIONALE

In the recent years, growing interest is focused on the use of platelet-rich plasma (PRP) in wound healing and tissue regeneration. There are a number of papers regarding the usefulness of PRP in the healing of ulcerations, skin injures, bone loss or distraction osteogenesis. Most authors emphasize the safety of PRP usage due to its authogenic nature.

PATIENT CONCERNS

We present a case of a 14 -year-old boy admitted to our department due to simple bone cyst of the distal tibia, qualified for injection of PRP into the cyst. PRP was separated with the use of Magellan Autologous Platelet Separator System (Arteriocyte Medical Systems Hopkington, MA) according to the manufacturers' manual. Immediately after separation during short-term IV anaesthesia, 3 mL of PRP was installed to the bone cyst under image intensifier control.

DIAGNOSES

Within the first 24 hours after exposure to PRP, the skin rash appeared. Physical examination revealed the small red papular, regionally purpuric eruptions, mainly concentrated on the upper extremities and on more warmed regions of skin, in association with pharyngitis, tonsillar enlargement, mucopurulent discharge in the posterior pharynx and swelling of the eyelids.

INTERVENTIONS

As the patient received calcium citrate with the PRP injection additional calcium citrate test were performed. Skin prick testing (negative) was and an intradermal test was positive (10×13 mm). Treatment included Claritine (Loratidinum) and Clemastin (Clemastinum)-both antihistaminic drugs.

OUTCOMES

All symptoms withdrew and the patient was released home after 4 days. The patient is in 6 years follow-up without any symptoms of allergic disease.

LESSONS

Our case shows that safety of use of PRP is not absolutely sure. The pure autologous tissue is safe, but preparation for its use can substantially decrease this safety. In our patient, only limited skin reaction to calcium citrate was observed, but general reaction leading to anaphylactic shock cannot be excluded. In order to reduce the risk of side effects skin test should be performed but as there were no records of allergic diseases on family and patients medical history this should apply to all patients.

Serum sickness disease in a patient with alopecia areata and Meniere' disease after PRP procedure

BACKGROUND

Platelet rich plasma procedure (PRP) is considered to be one of the safest aesthetic procedures. Adverse reactions after PRP administration are extreme rare.

PURPOSE

We present the patient with serum sickness disease (SSD) after PRP procedure.

OBJECTIVE AND METHODS

41 years old female suffers from alopecia areata for 5 years with frequent relapses and she has been suffering from Menier's disease recurrent symptoms for 6 years. The patient developed SSD after third PRP rejuvenating procedure and she has also noticed new alopecia areata lesions, but without Menier's disease symptoms. After SSD, 4 months later, she developed severe symptoms of Menier's disease with an episode of sudden sensorineural hearing loss. It alleviated only after intravenous administration of methylprednisolone. In our opinion, significant contraindication of PRP procedure is an autoimmune disease in the active phase.

The use of fat grafting and platelet-rich plasma for wound healing: A review of the current evidence

Fat grafting is becoming a common procedure in regenerative medicine because of its high content of growth factors and adipose derived stem cells (ADSCs) and the ease of harvest, safety, and low cost. The high concentration of ADSCs found in fat has the potential to differentiate into a wide range of wound-healing cells including fibroblasts and keratinocytes as well as demonstrating proangiogenic qualities. This suggests that fat could play an important role in wound healing. However retention rates of fat grafts are highly variable due in part to inconsistent vascularisation of the transplanted fat. Furthermore, conditions such as diabetes, which have a high prevalence of chronic wounds, reduce the potency and regenerative potential of ADSCs. Platelet-rich plasma (PRP) is an autologous blood product rich in growth factors, cell adhesion molecules, and cytokines. It has been hypothesised that PRP may have a positive effect on the survival and retention of fat grafts because of improved proliferation and differentiations of ADSCs, reduced inflammation, and improved vascularisation. There is also increasing interest in a possible synergistic effect that PRP may have on the healing potential of fat, although the evidence for this is very limited. In this review, we evaluate the evidence in both in vitro and animal studies on the mechanistic relationship between fat and PRP and how this translates to a benefit in wound healing. We also discuss future directions for both research and clinical practice on how to enhance the regenerative potential of the combination of PRP and fat.

Systematic review of the efficacy of fat grafting and platelet-rich plasma for wound healing

Adipose-derived stem cells found in fat grafts may have significant healing properties. When fat is combined with autologous platelet-rich plasma (PRP), there may be enhanced healing effects due to the pro-angiogenic and anti-inflammatory effects of PRP. This study aimed to evaluate the current evidence on fat grafting in combination with PRP for wound healing to establish the efficacy of this technique. A comprehensive search in the MEDLINE, EMBASE, CENTRAL, Science Citation Index, and Google Scholar databases (to March 2017) was conducted to identify studies on fat grafting and PRP for wound healing. Case series of less than 3 cases and studies only describing harvest technique were excluded. The database identified 571 articles, of which 3 articles that used a combination of fat and PRP for wound healing (1 RCT and 2 case series) were included in this review. A total of 69 wounds in 64 patients were treated with an average wound size of 36.32cm² . Of these, 67% of wounds achieved complete healing. When reported, the mean time to healing was 7.5 weeks for those who underwent a single treatment. There were no significant complications in any patients. The combination of fat grafting and PRP may achieve adequate wound healing with relatively quick wound healing time compared with standard wound management options. However, evidence is extremely limited, and further studies are required to evaluate its efficacy for wound healing.