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1.
Rev Bras Ortop (Sao Paulo) ; 59(4): e622-e625, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39239575

ABSTRACT

Giant cell tumors are benign but locally aggressive bone neoplasms containing many multinucleated giant cells similar to osteoclasts. The author reports the case of two patients with giant cell tumor in the metacarpals, one of whom was multicentric. Giant cell tumor in the hand is a rare condition, and, at this location, it commonly presents at an advanced stage, with extensive bone destruction. Thus, its safe resection, associated with a large resulting bone failure, represents a great challenge to the orthopedist. The various treatment options described in the literature cause severe cosmetic and/or functional impairment to the hand. Thinking about it, the author describes the treatment technique through the transfer of metatarsus-free osteoarticular graft to the metacarpal with good functional and cosmetic results.

2.
Rev Bras Ortop (Sao Paulo) ; 59(4): e519-e525, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39239581

ABSTRACT

Objective The present study aims to analyze histomorphometrically the repair of a non-critical bone defect after implantation of hydroxyapatite (HA) microspheres substituted by magnesium (Mg). Methods Thirty rats were distributed into 3 experimental groups, evaluated at 15 and 45 days postoperatively: HAG (bone defect filled with HA microspheres); HAMgG (bone defect filled with HA microspheres replaced with 1 mol% Mg), and CG (bone defect without implantation of biomaterials). Results After 15 days, the biomaterials filled the entire defect extent, forming a new osteoid matrix between the microspheres. In the CG, this neoformation was restricted to the edges with the deposition of loose connective tissue with reduced thickness. At 45 days, new bone formation filled almost the entire extension of the bone defect in the 3 groups, with statistically significant osteoid deposition in the CG despite the reduced thickness compared with the HAG and HAMgG. The groups with biomaterial implantation displayed a more abundant osteoid matrix than at 15 days. Conclusion The biomaterials studied showed biocompatibility, osteoconductivity, and bioactivity. The Mg concentration in the substituted HA did not stimulate more significant bone formation than HA without this ion.

3.
Rev Bras Ortop (Sao Paulo) ; 59(4): e532-e541, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39239585

ABSTRACT

Objective Although autologous bone grafting is the most widely used treatment for bone defects, the most effective preparation remains unclear. This animal study aimed to compare different autologous bone grafting preparation for the treatment of rat́s calvaria critical bone defect. Methods 122 rats were randomly allocated into three groups: Simulado, Macerated and Chopped. The specimens underwent craniotomies at the top center of their calvarias with a 7mm diameter circumferential cutter drill. The critical bone defect produced was treated or not according to the group the specimen wasallocated. The rats were euthanized at 3, 6 or 12 weeks post-op and its calvarias were analyzed by histomorphometry, bone densitometry, nanocomputed tomography (nCT), and biomechanical tests. Results The histomorphometry analysis showed the highest percentage of fulfillment of the critical bone defect in the chopped and macerated group when compared to simulado. The densitometry assessment evidenced higher bone mass at all endpoints analysis (p < 0.05) in the chopped group. The nCT data exhibited an expressive increase of bone in the chopped group when compared with the simulado and macerated groups. The biomechanical tests exhibited highest values of deformation, maximum force, and relative stiffness in the chopped group at any time of euthanasia (p < 0.05). Conclusions Our experimental work showed that chopped bone grafting preparation exhibited significant better outcomes than macerated in the treatment of a critical bone defect in rat́s calvaria.

4.
Periodontol 2000 ; 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39258791

ABSTRACT

This special issue on autologous platelet concentrates (APCs) provides clinicians with an overview on the current understanding of the use of these biomaterials for soft and hard-tissue regeneration. The included papers summarize scientific evidence and the clinical findings, presented in simple tables that outline potential benefits including Patient Reported Outcome Measures (PROMs). This approach enables clinicians to assess clinical relevance and researchers to identify significant gaps in the literature. The first part provides a comprehensive summary of the basic science surrounding APC, with particular focus on their preparation methods. Clear recommendations are outlined, which are crucial for obtaining high-quality APCs, alongside an exploration of how APCs may influence both soft and hard tissue healing processes. Part 2 delves into the clinical evidence for the potential benefits of APCs across a range of applications: alveolar ridge preservation, sinus floor elevation, periodontal plastic surgery, guided tissue regeneration, guided bone regeneration, the healing of Medication-Related Osteonecrosis of the Jaw (MRONJ), and endodontic surgery. In the part 3, the discussion turns to the effects of APCs on the healing of extra-oral wounds, including diabetic foot ulcers, venous leg ulcers, pressure injuries, burns, and more. For those clinicians persuaded by the evidence, the fourth section offers a detailed, step-by-step flowchart for each treatment modality, providing a clear guide for clinical application.

5.
Ann Med Surg (Lond) ; 86(9): 5627-5630, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39238960

ABSTRACT

Introduction and importance: Avascular necrosis (AVN) is a rare occurrence in the carpal region, especially in the triquetrum bone, which presents a diagnostic puzzle due to its infrequency and lack of trauma history. This case study explores the signs, diagnosis, and treatment of AVN in a healthy 22-year-old individual, emphasizing the need for early identification using suitable imaging methods. Case presentation: A 22-year-old patient complained of persistent wrist pain, specifically on the ulnar side, without any history of injury. Clinical examination revealed tenderness without signs of inflammation, with normal sensation and movement. Initial X-ray results were inconclusive, prompting further investigation with MRI, which showed a decrease in signal intensity in the triquetrum bone, leading to the diagnosis of AVN. Clinical discussion: The development of AVN involves compromised blood flow, often due to various factors. While AVN affecting carpal bones is uncommon, the triquetrum bone's robust blood supply typically protects against such conditions. However, this case highlights an exceptional occurrence. Gelberman's classification underscores the triquetrum's vascular nature, explaining why AVN is rare in this bone. MRI plays a crucial role in detecting AVN, especially when symptoms do not align with X-ray findings. Conclusion: Avascular necrosis should be considered in carpal bones, even without a history of trauma, with a focus on MRI for early detection. Although AVN of the triquetrum is rare, this case underscores the importance of timely recognition and conservative management. Further research is necessary to establish optimal treatment strategies for this unusual presentation.

6.
Radiol Case Rep ; 19(10): 4636-4643, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39220793

ABSTRACT

Osteoid Osteoma (OO) is a frequent benign bone tumor that commonly affects males between 5 and 25. It usually arises from appendicular skeleton involving typically femur and tibia. OOs arising from small bones of hands and feet are very uncommon and metatarsal lesions account for only 1.7%. We report a case of a 20 year-old boy with a long history of nocturnal left foot pain with a good clinical response to assumption of salicylates or nonsteroidal anti-inflammatory drugs (NSAIDs). Plain radiograph of his left showed unconclusive results. Therefore, he underwent a contrast enhanced CT (CECT) scan with multiplanar reconstruction (MPR) that showed a bony lesion in the left third metatarsal bone that was compatible with a nidus even in absence of clear peri-nidal sclerosis. Therefore, other ancillary techniques such as MRI and bone scintigraphy were performed. Conclusive diagnosis was OO of third left metatarsal bone. Our patient underwent a mini-invasive treatment with radiofrequency (RF) ablation. After recovery, our patient had no post-operative complications and showed optimal clinical conditions with complete remission of left foot pain and no change or impairment in walking. In this essay, we discuss key imaging findings of OO of small bones and its treatment with radiofrequency ablation. We describe method of execution and illustrate advantages of this mini-invasive technique. We also perform a review of the literature.

7.
Acta Bioeng Biomech ; 26(1): 133-142, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-39219083

ABSTRACT

Purpose: This study aimed to evaluate professional footwear comfort, functionality and style as well as their relationships with the foot structure among nurses. Methods: We examined 120 clinical nurses aged 40-50 years, occupationally active, wearing specific type of foot-wear at work for a minimum of 7 h a day, for 5 days prior to the research. The study relied on the CQ-ST podoscope for measurements of foot. Perception of footwear comfort, functionality and style scales were also used in the research. The results were analysed with the use of Mann-Whitney U-test and Spearman's rank correlation. Results: Statistically significant negative associations were found between right and left foot length and overall comfort of footwear ( p = 0.045, p = 0.045) as well as between right and left foot width and arch height ( p = 0.015, p = 0.028). Heel angle positively correlated with safety ( p = 0.008, p = 0.050), ease of donning and doffing ( p = 0.001, p = 0.004), as well as shoe style ratings ( p = 0.047). Variables determining shoe comfort were positively correlated with most shoe functionality characteristics as well as with shoe style (p < 0.05). Conclusions: Tested medical footwear meets the requirements of nurses in terms of comfort, functionality and aesthetics, and the studied features of footwear can be a useful guideline for the selection of shoes for representatives of this professional group. These footwear can be an element of workwear, and even, in the case of women with transverse flat feet - an alternative to ordinary utility shoes. There is a need to consider different widths for the same length size in medical footwear designs.


Subject(s)
Foot , Nurses , Shoes , Humans , Middle Aged , Adult , Foot/physiology , Foot/anatomy & histology , Female , Male
8.
ACS Biomater Sci Eng ; 10(9): 5439-5453, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39155744

ABSTRACT

Bone fracture plates are usually made from titanium alloy or stainless steel, which are much stiffer than bone. However, overly stiff plates can restrict axial interfragmentary motion at the fracture leading to delayed callus formation and healing, as well as causing bone "stress shielding" under the plate leading to bone atrophy, bone resorption, and plate loosening. Consequently, there have been many prior efforts to develop nonmetallic bone fracture plates with customized material properties using synthetic fibers (e.g., aramid, carbon, glass) in polymer resin. Even so, plant fibers (e.g., flax, roselle, sisal) offer additional advantages over synthetic fibers, such as availability, biodegradability, less toxicity during processing, lower financial cost, and recyclability. As such, there is an emerging interest in using plant fibers alone, or combined with synthetic fibers, to reinforce polymers for various applications. Thus, this is the first review article on the material properties and engineering performance of innovative bone fracture plates made from composite materials reinforced by plant fibers alone or supplemented using synthetic fibers. This article presents material-level fiber properties (e.g., elastic modulus, ultimate strength), material-level plate properties (e.g., fatigue strength, impact toughness), and bone-plate engineering performance (e.g., overall stiffness, plate stress), as well as discussing general findings, study quality, and future work. This article may help engineers and surgeons to design, fabricate, analyze, and utilize novel bone fracture plates.


Subject(s)
Bone Plates , Humans , Fractures, Bone , Materials Testing , Biocompatible Materials/chemistry
9.
Int. j. morphol ; 42(4)ago. 2024.
Article in English | LILACS-Express | LILACS | ID: biblio-1569246

ABSTRACT

SUMMARY: In this study, we aim to share the volumes of the carpal bone and the ratio of these volumes to the total volume of wrist bones from Computed Tomography (CT) images obtained from individuals of different ages and sex using 3D Slicer. Right wrist CT images of 0.625 mm slice thickness of 42 healthy individuals (21 female, 21 male) of both sexes were included in our study. Volume calculations were made by loading the images into 3D Slicer, an open-source software package. In this study, mean capitate volume was the largest in both sexes (male 3479.9±679.2; female 2207.1±272.1 mm3), while pisiform had the smallest mean volume (male 810.0±141.2; female 566.6±97.7 mm3). This order was ordered from largest to smallest as hamate, scaphoid, trapezium, lunate, triquetrum, trapezoid, and pisiform. According to this study, carpal bone volumes were larger in males than in females (p0.05). In this study, it was seen that carpal bone volume differed according to sex. However, it was observed that the bone volumes of both sexes took up the same amount in the total bone volume. This information will be very useful in sex determination, 3D anatomical material creation, implant applications and reconstructive surgery.


Nuestro objetivo fue determinar los volúmenes de los huesos del carpo y la relación entre estos volúmenes y el volumen total de estos huesos a partir de imágenes de TC obtenidas de individuos de diferentes edades y sexos utilizando 3D Slicer. En el estudio se incluyeron imágenes de TC del carpo de la mano derecha de los participantes en el estudio, con un grosor de corte de 0,625 mm, en 42 individuos sanos (21 mujeres, 21 hombres) de ambos sexos. Los cálculos de volumen se realizaron cargando las imágenes en 3D Slicer, un paquete de software de código abierto. El volumen medio del hueso capitado fue el mayor en ambos sexos (hombre 3479,9 ± 679,2; mujer 2207,1 ± 272,1 mm3), mientras que el hueso pisiforme tuvo el volumen medio más pequeño (hombre 810,0 ± 141,2; mujer 566,6 ± 97,7 mm3). De mayor a menor el volumen de los otros huesos fue: hamato, escafoides, trapecio, lunato, piramidal, trapezoide y pisiforme. Según este estudio, los volúmenes óseos del carpo eran mayores en hombres que en mujeres (p0,05). En este estudio se observó que el volumen de los huesos del carpo difería según el sexo. Sin embargo, se observó que los volúmenes óseos de ambos sexos ocuparon la misma cantidad del volumen óseo total. Esta información será de gran utilidad en la determinación del sexo, creación de material anatómico 3D, aplicaciones de implantes y cirugía reconstructiva.

10.
Surg Radiol Anat ; 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39093463

ABSTRACT

PURPOSE: Our aim in the study is to measure the area and volume of the tarsal bones and examine the typing of the talus and calcaneus joint surfaces according to sex. METHODS: In our study, the area and volume measurements of 630 tarsal bones and the morphology of the talus/calcaneus were analyzed by transferring thin-section Computed Tomography (CT) images to the 3D Slicer program. RESULTS: The volume and area sizes of the foot bones are calcaneus, talus, cuboid, navicular, medial cuneiform, lateral cuneiform, and intermediate cuneiform, respectively. All area and volume values of males were statistically higher than females (p < 0.05). The right side calcaneus area, intermediate cuneiform area, and lateral cuneiform area values were statistically higher than the left side (p < 0.045, p < 0.044, p < 0.030, respectively). There was no statistical relationship between age and area/volume values (p > 0.05). Three different types were seen in the calcaneus and seven in the talus. The most common type in the calcaneus was B1 (40%), and the least common type was A (27.8%). Regardless of the subgroups, the most common type in the talus was type B (37.8%), while the least common type was E2 (1.1%). CONCLUSION: Although morphometric measurements of tarsal bones differed according to sex, they did not differ according to age. The frequency of occurrence of the types of articular surfaces of the talus and calcaneus varies according to populations. We think that the morphometry and morphology of tarsal bones will contribute to invasive procedures regarding tarsal bones and surrounding structures, and that three-dimensional bone modeling can be used to create educational materials.

11.
Indian J Nephrol ; 34(3): 270-271, 2024.
Article in English | MEDLINE | ID: mdl-39114402

ABSTRACT

Renal Mucormycosis is a lethal opportunistic infection with extensive tissue invasion leading to infarction. We report a diabetic lady with disseminated fungal pyelonephritis presenting with extensive lytic bony lesions mimicking malignancy. Prompt initiation of antifungal therapy and surgical debridement is the key to successful management. A clinician should have a high index of suspicion for Mucormycosis in a patient with non-resolving pyelonephritis and prolonged fever.

12.
Animal ; 18(9): 101263, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39121724

ABSTRACT

Animal-derived foods (ADFs) are a very varied group of foods, but many are nutrient rich and contain higher quality protein than provided by plant-derived foods such that a simple replacement of ADF protein is likely to lead to a reduction in overall protein quality. In addition, many ADFs are richer in some nutrients than plant-based foods (e.g. Fe, Ca) and these often have a higher bioavailability. ADFs also provide nutrients that plants cannot supply (e.g. vitamin B12) and some provide beneficial health functionality (e.g. hypotensive) which is not explained by traditional nutrition. However, there remains a good health reason to increase the proportion of plant-derived food in many diets to increase the intake of dietary fibre which is often consumed at very sub-optimal levels. It seems logical that the increased plant-derived foods should replace the ADFs that have the least benefit, the greatest risk to health and the highest environmental impact. Processed meat fits these characteristics and should be an initial target for replacement with plant-based based protein-rich foods that additionally provide the necessary nutrients and have high-quality dietary fibre. Processed meat covers a wide range of products including several traditional foods (e.g. sausages) which will make decisions on food replacement challenging. There is therefore an urgent need for research to better define the relative health risks associated with the range of processed meat-based foods. The aim of this review is to examine the evidence on the benefits and risks of this dietary transition including the absolute necessity to consider initial nutrient status before the replacement of ADFs is considered.

13.
Phys Occup Ther Pediatr ; : 1-18, 2024 Aug 11.
Article in English | MEDLINE | ID: mdl-39129274

ABSTRACT

AIMS: The aims of this study were to: (1) synthesize existing evidence regarding the integration of students with osteogenesis imperfecta (OI) into the school setting, (2) tabulate existing school integration tools for OI, and (3) create an individualized school plan to facilitate school integration. METHODS: Guided by the process of developing evidence-informed guidelines, an international, interprofessional, expert task force was convened. The process entailed: (1) reviewing of the literature, (2) developing recommendations, and (3) creating a clinically meaningful, person-focused plan to facilitate the integration and promotion of school inclusivity. The 13-member task force relied on empirical studies, grey literature, and their experiential knowledge (from clinical, teaching or patient experiences) to devise the plan. RESULTS: Over a series of eight meetings and five drafts, the Task Force prioritized 14 core items for inclusion. These items consisted of general student information, fracture response protocol, student inclusion recommendations, mobility considerations, transfer considerations, toileting protocol, physical education recommendations, fieldtrip information, transportation considerations, evacuation plan, environmental and scholarly considerations, consent and authorization, and an annual renewal document. CONCLUSION: Further research is recommended to pilot the plan, solicit ongoing feedback, implement and evaluate the plan into routine education and health care practices.

14.
Article in English | MEDLINE | ID: mdl-39198277

ABSTRACT

OBJECTIVE: To describe and study retrospectively the combination of elastic nails and cementoplasty to stabilize pathological fractures in the upper limb and present the results on pain and mobility. MATERIALS AND METHODS: Between January 2022 and April 2024, six patients with a median age of 65 were treated with elastic nailing and cement injection. Pathological fractures were located in the clavicle (n = 3), humerus (n = 1) and radius (n = 2). Displacement at the fracture site was noted in two cases. RESULTS: All nails were inserted successfully. Two nails were used for the humerus (n = 1) and the radius (n = 2), and a single nail was used for the clavicle (n = 3). A median volume of 6.5 cc of PMMA was injected. Median duration of the procedure was 155 min. Median pain score dropped from 8/10 the day before intervention to 3.5/10 at 10 days of follow-up and 3/10 at one-month follow-up. Three patients could move their upper limb without limitation. For the five patients for whom imaging was available, no fracture displacement was recorded at a median last follow-up of 3 months. There was no delayed complication. CONCLUSION: The combination of elastic nail and cementoplasty is feasible and allows to reduce pain and restore limb function. It may offer an alternative to patients suffering from pathological fractures in the upper limb and who are not candidates for surgery.

15.
J Funct Biomater ; 15(8)2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39194650

ABSTRACT

Cuttlefish bones are byproducts of cuttlefish processing and are readily available in the marine food industry. In this study, calcium phosphate bioceramics were prepared from cuttlefish bones using a two-stage hydrothermal calcination process. The results indicated that all bioceramics derived from cuttlefish bones had a higher degradation capacity, better bone-like apatite formation ability, and higher degree of osteogenic differentiation than commercially available hydroxyapatite. Notably, ß-tricalcium phosphate, which had the highest degree of Ca2+ and Sr2+ dissolution among the bioceramics extracted, can significantly upregulate osteogenic markers (alkaline phosphatase, osteocalcin) and stimulate bone matrix mineralization. Thus, it is a promising bioceramic material for applications in bone regeneration.

16.
Int J Artif Organs ; : 3913988241269498, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39171422

ABSTRACT

AIM: The optimal preparation conditions of Salmon decalcified bone matrix (S-DBM) were explored, and the properties of S-DBM bone particles and bone powder were studied respectively. The therapeutic effect of S-DBM on tibial defect in female Sprague Dawley (SD) rats was preliminarily verified. METHODS: This study assessed the structural and functional similarities of Salmon bone DBM (S-DBM). The biocompatibility assessment was conducted using both in vivo and in vitro experiments, establishing an animal model featuring tibial defects in rats and on the L929 cell line, respectively. The control group, bovine DBM (bDBM), was compared to the S-DBM-treated tibial defect rats. Imaging and histology were used to study implant material changes, defect healing, osteoinductive repair, and degradation. RESULTS: The findings of our study indicate that S-DBM exhibits favorable repairing effects on bone defects, along with desirable physicochemical characteristics, safety, and osteogenic activity. CONCLUSIONS: The S-DBM holds significant potential as a medical biomaterial for treating bone defects, effectively fulfilling the clinical demands for materials used in bone tissue repair engineering.

17.
Article in English | MEDLINE | ID: mdl-39150993

ABSTRACT

CONTEXT: Skeletal dimensions vary between sexes. Men typically have broader shoulders and women a wider pelvis. If gender affirming hormone therapy (GAHT) with or without prior puberty suppression (PS) alters these dimensions in transgender individuals remains unclear. OBJECTIVE: To investigate impact of PS and GAHT on skeletal dimensions. DESIGN: Retrospective cross-sectional study. SETTING: Gender identity clinic. PARTICIPANTS: Transgender individuals assigned male at birth (AMAB) and assigned female at birth (AFAB) who underwent dual-energy X-ray absorptiometry (DXA) scanning between ages 18 and 28 years were divided into four groups: Early PS (Tanner G/B2-3)+GAHT, Late PS (Tanner G/B4-5)+GAHT, GAHT only, and Untreated. MAIN OUTCOME MEASURES: Shoulder and pelvis dimensions measured by DXA scan were compared between groups, with adjustment for height. RESULTS: A total of 121 individuals AMAB and 122 AFAB were included. Only in individuals AMAB who underwent early PS had smaller shoulders compared to untreated individuals AMAB (-1.3 cm; 95%CI -2.1; -0.5). In individuals AMAB from both the early and late PS group, pelvic inlet, pubic symphysis width and interischial distance were greater compared to untreated individuals AMAB resulting in dimensions comparable to untreated individuals AFAB. Only in early PS AFAB pelvic inlet width was smaller compared to untreated individuals AFAB (-1.0 cm; 95%CI -1.5; -0.6), and comparable to untreated individuals AMAB. CONCLUSIONS: The study results suggest that skeletal dimensions are only altered by GAHT if endogenous puberty has not yet been completed at start of PS. These findings enhance our understanding of hormonal effects on the skeleton and may hold clinical relevance for body image as well as for forensic anthropology. Future research should evaluate clinical implications for surgical or obstetrical outcomes in transgender individuals.

18.
J Nanobiotechnology ; 22(1): 525, 2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39217329

ABSTRACT

The complex anatomy and biology of craniofacial bones pose difficulties in their effective and precise reconstruction. Injectable hydrogels (IHs) with water-swollen networks are emerging as a shape-adaptive alternative for noninvasively rebuilding craniofacial bones. The advent of versatile nanomaterials (NMs) customizes IHs with strengthened mechanical properties and therapeutically favorable performance, presenting excellent contenders over traditional substitutes. Structurally, NM-reinforced IHs are energy dissipative and covalently crosslinked, providing the mechanics necessary to support craniofacial structures and physiological functions. Biofunctionally, incorporating unique NMs into IH expands a plethora of biological activities, including immunomodulatory, osteogenic, angiogenic, and antibacterial effects, further favoring controllable dynamic tissue regeneration. Mechanistically, NM-engineered IHs optimize the physical traits to direct cell responses, regulate intracellular signaling pathways, and control the release of biomolecules, collectively bestowing structure-induced features and multifunctionality. By encompassing state-of-the-art advances in NM-integrated IHs, this review offers a foundation for future clinical translation of craniofacial bone reconstruction.


Subject(s)
Bone Regeneration , Facial Bones , Hydrogels , Nanostructures , Tissue Engineering , Hydrogels/chemistry , Humans , Nanostructures/chemistry , Animals , Bone Regeneration/drug effects , Tissue Engineering/methods , Skull/drug effects , Osteogenesis/drug effects , Biocompatible Materials/chemistry , Tissue Scaffolds/chemistry
19.
Acta Biomater ; 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39214162

ABSTRACT

Currently, principles of tissue engineering and implantology are uniformly applied to all bone sites, disregarding inherent differences in collagen, mineral composition, and healing rates between craniofacial and long bones. These differences could potentially influence bone quality during the healing process. Evaluating bone quality during healing is crucial for understanding local mechanical properties in regeneration and implant osseointegration. However, site-specific changes in bone quality during healing remain poorly understood. In this study, we assessed newly formed bone quality in sub-critical defects in the maxilla and femur, while impairing collagen cross-linking using ß-aminopropionitrile (BAPN). Our findings revealed that femoral healing bone exhibited a 73% increase in bone volume but showed significantly greater viscoelastic and collagen changes compared to surrounding bone, leading to increased deformation during long-term loading and poorer bone quality in early healing. In contrast, the healing maxilla maintained equivalent hardness and viscoelastic constants compared to surrounding bone, with minimal new bone formation and consistent bone quality. However, BAPN-impaired collagen cross-linking induced viscoelastic changes in the healing maxilla, with no further changes observed in the femur. These results challenge the conventional belief that increased bone volume correlates with enhanced tissue-level bone quality, providing crucial insights for tissue engineering and site-specific implant strategies. The observed differences in bone quality between sites underscore the need for a nuanced approach in assessing the success of regeneration and implant designs and emphasize the importance of exploring site-specific tissue engineering interventions. STATEMENT OF SIGNIFICANCE: Accurate measurement of bone quality is crucial for tissue engineering and implant therapies. Bone quality varies between craniofacial and long bones, yet it's often overlooked in the healing process. Our study is the first to comprehensively analyze bone quality during healing in both the maxilla and femur. Surprisingly, despite significant volume increase, femur healing bone had poorer quality compared to the surrounding bone. Conversely, maxilla healing bone maintained consistent quality despite minimal bone formation. Impaired collagen diminished maxillary healing bone quality, but had no further effect on femur bone quality. These findings challenge the notion that more bone volume equals better quality, offering insights for improving tissue engineering and implant strategies for different bone sites.

20.
J Exp Biol ; 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39210868

ABSTRACT

Jumping is a crucial behavior in fitness-critical activities including locomotion, resource acquisition, courtship displays, and predator avoidance. In primates, paleontological evidence suggests selection for enhanced jumping ability during their early evolution. However, our interpretation of the fossil record remains limited, as no studies have explicitly linked levels of jumping performance with interspecific skeletal variation. We used force platform analyses to generate biomechanical data on maximal jumping performance in three genera of callitrichine monkeys falling along a continuum of jumping propensity: Callimico (relatively high propensity jumper), Saguinus (intermediate jumping propensity), and Callithrix (relatively low propensity jumper). Individuals performed vertical jumps to perches of increasing height within a custom-built tower. We coupled performance data with high-resolution µCT data quantifying bony features thought to reflect jumping ability. Levels of maximal performance between species - e.g., maximal takeoff velocity of the center of mass (CoM) - parallel established gradients of jumping propensity. Both biomechanical analysis of jumping performance determinants (e.g., CoM displacement, maximal force production, peak mechanical power during push-off) and multivariate analyses of bony hindlimb morphology highlight different mechanical strategies among taxa. For instance, Callimico, which has relatively long hindlimbs, followed a strategy of fully extending of the limbs to maximize CoM displacement - rather than force production - during push-off. In contrast, relatively shorter-limbed Callithrix depended mostly on relatively high push-off forces. Overall, these results suggest that leaping performance is at least partially associated with correlated anatomical and behavioral adaptations, suggesting the possibility of better inferring performance from the fossil record.

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