Globally there is a shortage of available donor corneas with only 1 cornea available for every 70 needed. A large limitation to corneal transplant surgery is access to quality donor tissue due to inadequate eye donation services and infrastructure in many countries, compounded by the fact that there are few available long-term storage solutions for effectively preserving spare donor corneas collected in countries with a surplus. In this study, we describe a novel technology termed low-temperature vacuum evaporation (LTVE) that can effectively dry-preserve surplus donor corneal tissue, allowing it to be stored for approximately 5 years, shipped at room temperature, and stored on hospital shelves before rehydration prior to ophthalmic surgery. The dry-preserved corneas demonstrate equivalent biological characteristics to non-dried donor tissue, with the exception that epithelial and endothelial cells are removed and keratocytes are rendered non-viable and encapsulated within the preserved extracellular matrix. Structure and composition of the dried and rehydrated corneas remained identical to that of non-dried control corneas. Matrix-bound cytokines and growth factors were not affected by the drying and rehydration of the corneas. The ability to preserve human donor corneas using LTVE will have considerable impact on global corneal supply; utilisation of preserved corneas in lamellar keratoplasties, corneal perforations, ulcers, and tectonic support, will allow non-preserved donor tissue to be reserved for where it is truly required.

In the quest for an ideal wound healing material, human amniotic membrane (AM), tilapia skin collagen (TSC), and Centella asiatica (CA) have been studied separately for their healing potential. In this study, we formulated AM, TSC, and CA gel and studied their competency and wound healing efficacy in vivo. Gel was formulated using AM, TSC, CA, Carbopol 934, acrylic acid, glycerine, and triethanolamine and physicochemical properties e.g.,pH, water absorption, swelling variation, and nuclear magnetic resonance (NMR) spectroscopy were determined. Biological properties were determined by skin irritation study, brine shrimp lethality, andantibacterial activity. Wound healing potential was determined by applying gel to second-degree burnsin vivoby observing wound contracture, epithelialization period, and histological features. The gel was non-lethal to brine shrimp and had anti-bacterial activity and showed no edema or erythema after 7 days of topical application. After 21 days of treatment, the AM + TSC + CA group significantly (P < 0.001) accelerated wound contraction (95.75 ± 0.44%)whereasthenegative control had the lowest healing rate (40.32 ± 2.11%). Wound contraction rates of AM + TSC and TSC + CA groups were (68.12 ± 1.46%) and (82.52 ± 1.74%) respectively.Epithelialization period for AM + TSC + CA was only 22.7days whereas AM, TSC, CA, AM + TSC, AM + CA, TSC + CA, positive control, and negative control needed 29.3, 30.7, 31.3, 27.3, 26, 26.6, 25.3 and 36.6 days respectively. Histological analysis showed better healing potential for AM + TSC + CA regarding epidermal regeneration, blood vessel formation, and collagen deposition. The gel was biocompatible and in vivostudies with Wistar rats exhibited better wound healing capabilities than individual components of the gel alone.

This study aimed to investigate whether extracellular vesicles (EVs) derived from adipose-derived mesenchymal stem cells (ASCs) promote skin wound healing by delivering basic fibroblast growth factor (bFGF) to enhance vascular endothelial growth factor (VEGF) expression. ASCs were isolated and transfected with either a bFGF knockdown lentivirus (Lv-sh-bFGF) or a control lentivirus (Lv-sh-NC). EVs were extracted from ASCs cultures and characterized by transmission electron microscopy, nanoparticle tracking analysis, and Western blotting for surface markers. EVs were extracted from the conditioned mediums of ASCs and subjected to different treatments. These EVs or control treatments were injected at the wound edges. Wound healing was assessed using histological techniques, including H&E and Masson's trichrome staining to evaluate tissue regeneration, collagen organization, and immunohistochemistry for CD31 to quantify microvessel density. Protein expression of bFGF and VEGF was measured by Western blotting. ASC-derived EVs significantly promoted angiogenesis and improved skin wound healing. EVs encapsulating bFGF enhanced VEGF expression in the wound tissue, while knockdown of bFGF reduced both bFGF and VEGF expression, leading to delayed wound healing. Further knockdown of VEGF partially reversed the pro-angiogenic and wound-healing effects of bFGF-encapsulated EVs. This study demonstrates that ASC-derived EVs promoted skin wound repair by enhancing angiogenesis and accelerating tissue regeneration through the bFGF/VEGF axis. These findings highlight the therapeutic potential of ASCs-derived EVs in improving skin wound healing.

Non-healing wounds cost the National Health Service over £5.6 billion annually in wound management. Skin allografts are used to treat non-healing wounds, ulcers and burns, offering the best protection against infection. In order to allow host cells to repopulate and to avoid immunogenicity, cell components are removed through decellularisation. Decellularisation of human dermis has so far been performed in NHS Blood and Transplant using a combination of two enzymes (RNase T1 and the recombinant human DNase Pulmozyme)®. This study aims at validating a new method to remove DNA from donated dermis via the use of a single enzyme, Benzonase, known for its effectiveness of DNA digestion. Skin samples were decellularised by removing the epidermis, lysing of dermal cells, removal of cellular fragments by a detergent wash and removal of nucleic acids by a nuclease incubation with either Benzonase or Pulmozyme + RNase T1. DNA quantification with PicoGreen, as well as histology on wax-embedded biopsies, stained with DAPI and haemotoxylin and eosin, were performed. In vitro toxicity test on human osteosarcoma immortalised cells and skin fibroblasts, and biomechanical (tensile) testing, were also performed. The effectiveness of DNA digestion with the new methodology was comparable to previous procedure. Mean DNA removal percentage following decellularisation with Pulmozyme + RNase was 99.9% (3.83 ng/mg). Mean DNA removal percentage with Benzonase was 99.8% (9.97 ng/mg). Histology staining showed complete decellularisation following either method. Benzonase was proven to be non-toxic to both cell lines used, and a one-way Anova test showed no significant difference in neither stress nor strain between acellular dermal matrix decellularised with either Benzonase or Pulmozyme + RNase T1. Benzonase was able to effectively decellularise dermis after prior removal of epidermis. It performed just as well as the combination of Pulmozyme + RNase T1, but represents significant advantages in terms of cost effectiveness, procurement and storage; Benzonase has been successfully used in the decellularisation of other tissues, thus would be better for Tissue Banking use. Switching to this combined DNase/RNase can have far-reaching consequences in the production of acellular human dermal matrix by NHSBT and in the treatment of patients requiring it.

Amniotic membrane is arguably one of the most popular biological wound dressings on the market today. Various growth factors and cytokines inherent to amniotic membrane tissue have been recognized as key mediators in wound healing and tissue regeneration, giving the tissue its clinical utility. Sterilization methodologies using irradiation are recognized as the gold standard in the field and routinely used to prepare tissue allografts, including amniotic membrane for transplantation. However, irradiation is not always compatible in preserving the physical structure or biochemical factors of biological materials and can potentially result in detrimental effects to the critical quality attributes of allograft tissues. Alternatively, a novel sterilization technique involving supercritical carbon dioxide (SCCO) has been shown to have minimal effect on the inherent biophysical properties of sensitive biological tissues and tissue-derived products. At BioBridge Global, we have developed a process utilizing SCCO technology for the sterilization of an amniotic membrane tissue allograft product. This process, first and foremost, meets industry standards for sterilization while simultaneously maintaining the biochemical composition of the tissue. Our results show that upon SCCO sterilization, most of the growth factors tested were conserved, with many at quantities significantly greater than commercially available gamma and electron beam irradiated tissue. The SCCO-sterilized amniotic membrane allograft is unique in that it is designed to overcome limitations associated with traditional tissue sterilization methodologies, namely, the conservation of key biological factors inherent to native amniotic membrane tissue. It is anticipated that by retaining these biological factors, clinical outcomes associated with the use of SCCO-sterilized amniotic membrane will be improved.

Tissue engineering and cartilage transplantation constitute an evolving field in the treatment of osteoarthritis, with therapeutic and clinical promise shown in autologous chondrocyte implantation. The aim of this systematic review is to explore current clinical trials that utilized autologous chondrocyte transplantation (ACT) and assess its efficacy in the treatment of osteoarthritis. PubMed, Ovid MEDLINE, and Google-Scholar (pages 1-20) were searched up until February 2023. Inclusion criteria consisted of clinical trials that involve autologous cartilage transplantation for the treatment of osteoarthritis. Clinical, imaging, arthroscopic, and histologic outcomes were assessed. A total of 15 clinical trials, involving 851 participants, were included in the study. All trials utilized ACT in the treatment of knee osteoarthritis through varying scaffolds: collagen-based (10 trials), polymer-based (2 trials), hyaluronic-acid based (2 trials), and spheroid technology (1 trial). Clinical improvement of patients undergoing ACT was noted in 14 trials; five showed superior clinical outcomes compared to the control group, while one showed inferiority compared to mesenchymal stem cells. Postoperative imaging was utilized to assess the degree of cartilage regeneration in 11 trials. Ten trials showed signs of cartilage recovery with ACT, four trials showed no difference, and two showed worse outcomes when compared to controls. Second-look-arthroscopy was performed in three trials, which reported varying degrees of improvement in cartilage regeneration. Histologic analysis was performed in four trials and generally showed promising results. While improved clinical outcomes were demonstrated, conflicting findings in postoperative outcome analysis raise questions about the unequivocal utility of ACT. Additional research with control groups, randomization, and appropriate blinding is required.

Interactions between MSCs and cancer cells are complex and multifaceted and have been shown to exhibit both pro-tumor and antitumor effects. This study investigated the effects of conditioned medium (CM) and cell extract (CE) from two different ERα statuses, MCF-7 and MDA-MB-231 breast cancer cell lines, on adipose-derived mesenchymal stem cells (ASCs). Findings showed that CM and CE increased cellular metabolic activity and viability of ASCs, upregulated angiogenic factors VEGF and HIF-1α, and cytokine TGF-β expression levels. However, CM and CE treatment did not significantly affect the clonogenicity of ASCs. In addition, apoptosis-related genes caspase-3 and 9 showed differential expression patterns among the treatment groups. The findings suggest that breast cancer cell-derived factors can modulate the behavior of ASCs, highlighting their potential as a therapeutic tool in breast cancer treatment and tissue regeneration. However, it is essential to consider the potential risks associated with CM and CE treatment on ASCs, as well as the potential recruitment of ASCs by cancer tumors and the risks associated with this recruitment. Further research is needed to elucidate these potential risks and benefits.

Bowman's layer is an acellular corneal structure, which is considered to be a specially modified anterior stroma. It is presumed, that it forms as a result of ongoing epithelial-stromal interactions and no clear physiological purpose has been proven. Despite this fact, Bowman's layer has found its place in corneal transplantation. It has been performed for over a decade, mainly in treatment of advanced keratoconus with multiple modifications. Transplantation of Bowman's layer can be expected to become a widely used surgical procedure in the treatment of many corneal pathologies involving fragmentation and destruction of Bowman's layer. This article aims to summarize information available on its structure, possible function, and transplantation. A thorough literature search was performed in the PubMed database and Google Scholar using keywords: Bowman's layer, structure, function, preparation and corneal transplantation. All the relevant sources were used, which represent 77 peer-reviewed articles with information corcerning the topic of this article.

It is common practice that allograft tissues for knee multiligament reconstruction, meniscus transplantation, cartilage replacement and other advanced procedures are made available through commercial banks. The aim was to present the 10-year experience with a local, non-commercial tissue bank, established in 2014. The allograft bank was connected to an existing organ donor program. Following organ procurement, the musculoskeletal tissue is removed and stored immediately, fresh frozen to - 80 degrees Celsius (except hyaline cartilage, which is stored at 5 degrees Celsius). The donor is tested for contagious disease and the grafts for bacteria. When all results are negative, the grafts are released. When thawed before use a swap is cultured. Consecutive, prospectively collected data were analyzed. There were 31 donations, resulting in 1160 grafts. Only 40 grafts (3.4%) had a positive bacteria culture and were discarded. 552 recipients have been treated by use of these allografts. All grafts had negative bacterial cultures in swaps obtained before thawing, and there were no recorded transplantation related complications. The expenses for local grafts were 10-15% of the costs for grafts obtained from foreign banks. Through the local donation program, it was possible to establish a tissue bank with controlled quality grafts at minimal costs, minimizing the need for transportation of frozen grafts retrieved in other countries. Centers for specialized orthopedic surgery using allograft tissue can be self-providing and reduce costs by retrieving and handling allograft tissues locally.

Cryoinjury mitigation is key in cell cryopreservation. Here, we aimed to assess the effectiveness of nanographene oxide (nano-GO) for improving cryoprotectant agents (CPAs) in human adipose stem cell (hADSC) cryopreservation. For in vitro experiments, nano-GO (5 μg/mL) was added to the CPAs in the control, and passage (P) 2 hADSCs were collected and cryopreserved for around two weeks. We compared cytotoxicity, cell viability, immunophenotypes, proliferation, cell apoptosis, and tri-lineage differentiation. In vivo, studies used lipoaspirate to create non-enriched or hADSC-enriched fat tissues by combining it with PBS or hADSCs cryopreserved with the aforementioned CPAs. Each nude mouse received a 0.3 mL subcutaneous injection of the graft. At 12 weeks, the grafts were harvested. Histology, adipocyte-associated genes and protein, vascular density and angiogenic cytokines, macrophage infiltration, and inflammatory cytokines were analyzed. Nano-GO CPA contributed to increased cell viability, improved cell recovery, and lowered levels of early apoptosis. Nano GO at concentrations of 0.01-100 μg/mL caused no cytotoxicity to hADSCs. The absence of nano GOs in the intracellular compartments of the cells was confirmed by transmission electron microscopy. The fat grafts from the CPA-GO group showed more viable adipocytes and significantly increased angiogenesis compared to the PBS and CPA-C groups. Adding hADSCs from the CPA-GO group to the graft reduced macrophage infiltration and MCP-1 expression. Nano-GO plays an anti-apoptotic role in the cryopreservation of hADSCs, which could improve the survival of transplanted fat tissues, possibly via improved angiogenesis and lower inflammatory response in the transplanted adipose tissue.

Severe burns often result in an exacerbated inflammatory response, which can contribute to further injury. This inflammatory response may lead to an increased risk of infection, multiple organ failure, and death. This study aimed to investigate the potential of reducing inflammation to enhance burn wound healing in rats using ovine's small intestinal submucosa as a carrier for Wharton's jelly mesenchymal stem cells (WJ-MSCs) and Mineral Pitch (MP). A rat burn model was developed, and the animals were divided into four groups: control group: burn, placebo group: scaffold-treated burn, cell experimental group: WJ-MSCs seeded scaffold-treated burn, and cell and MP experimental group: scaffolds loaded with WJ-MSCs and MP-treated burn. After treating the wounds in the relevant groups and sampling them on days 5, 14 and 21, histological and pathological parameters, and the expression of genes involved in angiogenesis and epithelialization were evaluated. The study results revealed several findings in the burn wounds. These included changes in mast cell populations, a decrease in inflammatory neutrophils and lymphocytes, an increase in fibroblasts and blood vessels, and upregulation of angiogenesis and epithelialization genes. These changes collectively contributed to enhanced wound healing in cell and MP experimental group compared to the other groups. The findings suggest that scaffolds loaded with Wharton's jelly-derived stem cells and MP can serve as engineered tools to modulate inflammatory conditions during the burn wound healing process. These interventions can improve burn wound management and promote better outcomes.

The aim of this study was to evaluate the effect of adipose-derived stem cells (ADSCs) in the treatment of acute rupture of the Achilles tendon. It was a cross-sectional study involving 15 patients. Patients were randomly divided: group 1-rupture; group 2-suture; group 3-rupture + ADSCs. In the AOFAS score, the score was higher in group 3 with a significant difference. In the ATRS score, the score was higher in groups 2 and 3, also with a significant difference. As for the ultrasound score, there was a significant difference between the experimental groups in relation to this score, however, in the multiple comparisons test, comparing two groups at a time, it was possible to observe a significant difference of the experimental groups. It can be concluded that cell therapy in this condition may be a treatment option due to tissue regeneration and significant recovery of function.

A high success rate of corneal transplants is evident. However, there is still a lack of corneal grafts available to meet demand, largely because donors are reluctant to donate. Given their critical role in future healthcare teaching and advocacy. There has not been much research on Jordanian nursing students' perspectives on corneal donation, so it's critical to identify and eliminate any obstacles. This study aims to evaluate the knowledge and attitudes of Jordanian nursing students concerning corneal donation. A cross-sectional, descriptive design was used to recruit (n = 440) nursing students from four Jordanian universities. A self-reported questionnaire was used to obtain data on knowledge and attitudes regarding corneal donation. The average age of senior nursing students was (M = 23.07, SD = 3.63) years. Varying levels of understanding were revealed amongst university students toward corneal donation items. Generally, good attitude of nursing students toward corneal donation (M = 34.1, SD = 8.1). Weak positive relationship was found between total knowledge scores and age (r = 0.141, p = 0.003) while there is no significant relationship between age and total attitude score (r = 0.031, p = 0.552). Age was found to be a significant predictor (B = 0.01, Beta = 0.12, t = 2.07, p = 0.04). Also, the educational level of fathers is a significant positive predictor (Beta = 0.128, p = 0.008) for the total attitude scores among nursing students. Limited awareness of corneal donation, highlighting the need for focused educational interventions to improve their comprehension.

An injury that affects the integrity of the skin, either inside or externally, is called a wound. Damaged tissue is repaired by a set of cellular and molecular mechanisms known as wound healing. Quercetin, a naturally occurring flavonoid, may hasten the healing of wounds. The study's objective was to investigate any potential impacts of quercetin on the wound-healing process. Human umbilical vein endothelial cells (HUVECs) were treated to varying dose ranges of quercetin (5-320 nM) for 24 and 48 h. Cultured cells were evaluated by using the MTT analysis, wound scratch assay and vascular tube formation. Furthermore the gene expression of VEGF and FGF were evaluated by qRT-PCR to determine the effects of quercetin on angiogenezis and wound repair. Positive effects of quercetin on cellular viability were demonstrated by the MTT experiment. In HUVECs quercetin promoted tube formation, migration, and proliferation while also averting wound breakage. Moreover, quercetin increased the expression of the FGF and VEGF genes, which aid in the healing of wounds in HUVECs. Quercetin may be bioactive molecule that successfully speeds up wound healing by regulating the vasculogenezis and healing cells.

Cryopreservation is a method adopted for storage of autologous skulls. Herein, this current research sought to explore the effects of different cryoprotectants on the biological characteristics of rat calvarial osteoblasts after cryopreservation. Neonatal Sprague-Dawley rats were selected and their skull tissues were isolated. The skull tissues were allocated into the refrigerating-3M, refrigerating-6M, M199-3M, M199-6M, povidone iodine-3M, and povidone iodine-6M groups according to the usage of cryoprotectants and treatment time (month) and the fresh group. Osteoblasts were isolated from skull tissues in each group through digestion. The histomorphology of the skull was evaluated by H&E staining and cell morphology was observed by microscopy. The viability, proliferation, apoptosis, and osteogenic activity of osteoblasts were assessed by trypan blue staining, MTT, flow cytometry, and alkaline phosphatase (ALP) staining. The skull histomorphology and osteoblast morphology were similar between the fresh and refrigerating groups. Osteoblast viability was weakened after cryopreservation. The longer the refrigeration time, the lower the number of living cells and the higher the apoptosis rate. However, cryopreservation using different cryoprotectants did not evidently affect osteoblast proliferation and ALP activity. Different cryoprotectants show no apparent effect on the osteogenic activity of rat calvarial osteoblasts after cryopreservation.

When addressing bone defects resulting from trauma, infection, or tumors, the use of allogenic bone is often necessary. While autografts are considered the standard, they have limitations and can lead to donor site morbidity. Consequently, there has been exploration into the feasibility of utilizing allogenic bone and bone graft replacements. Allogenic bone transplants are acquired from donors following rigorous procurement, sterile processing, and donor screening procedures. To ensure the safe storage and effective utilization of allograft material, a bone banking system is employed. Establishing and managing an orthopedic bone bank, entails navigating complex legal and medical organizational aspects. This paper examines the establishment and operation of bone banks in India, drawing upon our first-hand experience in managing one at a tertiary care center in Northern India.Level of evidence: Level IV.

Odense University Hospital is a major tertiary vascular hospital in Scandinavia, performing approx. 200 aortic repairs annually. This article presents the rationale behind this endeavor and the early outcomes of the initial implantation of locally processed homografts. All patients receiving a homograft were identified from the established homograft biobank database and their medical records were reviewed after obtaining consent. All surgeons in charge of homograft implantations were semi structured interviewed regarding the harvesting procedure, the tools for detecting available homografts, their quality and delivery. The National board of Health approved the biobank fulling the EU Directive of Tissues and Cells after 18 months of preparation. From May 6, 2021, to March 1, 2023, 26 patients had a homograft implantation, with 7 for mycotic aneurysms, 10 for aorto-iliac graft infection, 6 for infra-inguinal graft infection, and 3 for graft infection in thoracic aorta. Six (23%) were emergently performed. Two (7.7%) died within 30 days postoperatively, both following in situ replacement of an infected aortoiliac graft, corresponding to a 20% mortality in this subgroup. The incidence of reinfections was 19.2%; one each in the mycotic aneurysm group, the aortoiliac graft infection group, and the thoracic graft infection group. After 90 days, two patients were diagnosed with aorto-enteric fistula. All involved surgeons could easily identify available suitable homografts, and within 2 h have homografts of acceptable quality and requested dimensions. The establishment of the Danish Cardiovascular Homograft Biobank was straightforward and effectively serves cardiovascular procedures performed 24/7. Additionally, the initial experiences seem comparable to others experiences.

In this experimental study, we compared the structural integrity and cell quality of corneal endothelium stored in organ culture medium (OCS) and Eusol-C. The experiment included rabbit and human cornea experiments in vitro. Thirty rabbit corneas and thirty-two human corneas were collected and divided into two groups. All right corneas were allocated in experiment group and left corneas were placed in control group. The corneas in experimental group were stored in OCS at 34 °C, and the corneas in control group were stored in Eusol-C at 4 °C for 7, 14, 21, 28, and 35 days, respectively. Endothelial cell morphology, cell count, and trypan blue staining for viability were assessed before storage (Day 0) and at days 7, 14, 21, 28 and 35. The structural integrity of human corneal endothelial cell was analyzed using immunohistochemistry. The samples of storage solution for microbial culture were collected on the third day and at the end of storage. The results show that no bacterial and fungal infections were found in both groups. After 14 days of storage, the morphology of endothelial cell was better in the experimental group than in the control group. The endothelial cell stored in OCS were better than those stored in Eusol-C at the end of storage times, except human cornea 14 days storage group. The ZO-1 protein staining showed the typical polygonal morphology of endothelial cell stored in the OCS. Corneal endothelial cells stored in the OCS had better quality up to 28 days. It can be applied to Chinese eye banks as a method of corneal preservation.

Decellularization is regarded as a xenogenic antigen-reduction technique because it effectively eliminates all cellular and nuclear components while mitigating any negative impact on the composition, biological functionality, and structural integrity of the remaining extracellular matrix. This study aimed to histologically evaluate native, freeze dried and chemically decellularized bovine pericardium membrane. Also, this study focused on preservation of extracellular matrix after decellularization. Bovine pericardium membrane was decellularized by freeze thaw cycle followed by freeze drying and 1% sodium dodecyl sulphate. Unprocessed pericardium was used as control. The effectiveness of Decellularization was assessed based on the reduction of histologically visible nuclei. Decellularization by freeze thaw cycle followed by freeze drying resulted in 17.84% reduction in nuclei content and decellularization by sodium dodecyl sulphate results in 92% reduction in nuclei content compare to control group. Picrosirius red staining for freeze dried group displayed loosely organised, thin collagen bundles that exhibit reddish-yellow birefringence and sodium dodecyl sulfate group revealed dense collagen bundles that are parallelly organised and compact, exhibiting reddish-yellow birefringence and showed good structural integrity. These results suggested that the sodium do decyl sulfate showed optimal decellularization results with better extracellular matrix preservation. It may be a suitable protocol for producing a suitable scaffold for periodontal tissue regeneration.

The femoral head is one of the most commonly used bones for allografts and biomechanical studies. However, there are few reports on the trabecular bone microarchitectural parameters of freshly harvested trabecular bones. To our knowledge, this is the first study to characterize the microstructure of femoral heads tested immediately after surgery and compare it with the microstructure obtained with conventional freezing. This study aims to investigate whether freezing at -80 °C for 6 weeks affects the trabecular microstructure of freshly harvested bone tissue. This study was divided into two groups: one with freshly harvested human femoral heads and the other with the same human femoral heads frozen at -80 °C for 6 weeks. Each femoral head was scanned using an X-ray microcomputed tomography scanner (µCT) to obtain the microarchitectural parameters, including the bone volume fraction (BV/TV), the mean trabecular thickness (Tb.th), the trabecular separation (Tb.sp), the degree of anisotropy (DA), and the connectivity density (Conn.D). There was no statistically significant difference between the fresh and the frozen groups for any of the parameters measured. This study shows that freezing at -80 °C for 6 weeks does not alter bone microstructure compared with freshly harvested femoral heads tested immediately after surgery.