Spare Roof Technique Versus Component Dorsal Hump Reduction: A Randomized Prospective Study in 250 Primary Rhinoplasties, Aesthetic and Functional Outcomes.

BACKGROUND: Most Caucasian aesthetic rhinoplasty patients complain about having a noticeable hump in profile view. Taking the integrity of the middle vault into consideration, there are 2 ways to dehump a nose: the structured technique and the preservation technique. OBJECTIVES: The aim of this study was to compare the aesthetic and functional outcomes of 2 reduction rhinoplasty techniques. METHODS: We performed a prospective, randomized, interventional, and longitudinal study on 250 patients randomly divided into 2 groups: the component dorsal hump reduction group (CDRg) (n = 125) and the spare roof technique group (SRTg) (n = 125). We utilized the Utrecht Questionnaire for Outcome Assessment in Aesthetic Rhinoplasty. Patients answered the questionnaire before the surgery, and at 3 and 12 months after surgery. In addition, we utilized a visual analog scale (VAS) to score nasal patency for each side. RESULTS: Analyses of the preoperative and postoperative aesthetic VAS scores showed a significant improvement in both groups, from 3.66 to 7.00 (at 3 months) to 7.35 (at 12 months) in the CDRg, and from 3.81 to 8.14 (at 3 months) to 8.45 (at 12 months) in the SRTg. Analyses of postoperative means of aesthetic VAS scores showed a significant improvement in both groups over time. However, aesthetic improvement was higher in the SRTg than in the CDRg at both 3 (P < 0.001) and 12 months (P < 0.001) postsurgery. Analyses of the mean functional VAS scores showed a significant improvement with both techniques, with a better result for the SRTg. CONCLUSIONS: The SRT is a reliable technique that can help deliver consistently better aesthetic and functional results than CDR for reduction rhinoplasty in Caucasian patients with a dorsal hump.

Dorsal Hump Reduction Based on the New Ethmoidal Point Classification: A Clinical and Radiological Study of the Keystone Area in 138 Patients.

BACKGROUND: Hump resection often requires reorganization of the keystone area. OBJECTIVES: The authors sought to describe the importance of the point where the perpendicular plate of ethmoid joins the septal cartilage (SC) and the nasal bones (NB) (Ethmoidal point [E-point]) for hump resection surgical planning. METHODS: Measurements from mid-sagittal slices in nasal computed tomography scans taken in adult Caucasian patients between January 2015 and December 2018 were compared between patients seeking primary rhinoplasty due to a nasal hump and patients not seeking rhinoplasty (control group). Patients with previous nasal surgery or trauma, genetic or congenital facial disorders, and high septal deviation were excluded. The length of overlap between NB and SC was compared between the 2 groups. The location of the E-point in relation to the beginning of the nasal hump in the cephalocaudal direction was documented in the patients seeking rhinoplasty. RESULTS: The study population included 138 patients, 69 seeking and 69 not seeking rhinoplasty (96 females). The mean age was 32.9 years (range, 18-55 years). The length of overlap between NB and SC was similar between both groups (11.7 ±â€…3.3 vs 10.8 ±â€…3.3; P = 0.235). The E-point was located before the beginning of the nasal hump in 97% (67/69) of nasal hump patients, and it could be found a mean distance of 2.3 (±2.3) mm cephalic to the latter. CONCLUSIONS: As a rule, the perpendicular plate of the ethmoid does not contribute to the nasal hump; therefore, only in exceptional cases should this be addressed while performing dorsal reduction.

Preclinical and Translational Studies in Small Ruminants (Sheep and Goat) as Models for Osteoporosis Research.

PURPOSE OF THE REVIEW: This review summarizes research on the use of sheep and goats as large animal models of human osteoporosis for preclinical and translational studies. RECENT FINDINGS: The most frequent osteoporotic sheep model used is the ovariectomized sheep with 12 months post-operatively or more and the combined treatment of ovariectomized sheep associated to calcium/vitamin D-deficient diet and glucocorticoid applications for 6 months, but other methods are also described, like pinealectomy or hypothalamic-pituitary disconnection in ovariectomized sheep. The goat model for osteoporosis research has been used in a very limited number of studies in osteoporosis research relative to sheep. These osteoporotic small ruminant models are applied for biomaterial research, bone augmentation, efficacy of implant fixation, fragility fracture-healing process improvement, or bone-defect repair studies in the osteopenic or osteoporotic bone. Sheep are a recognized large animal model for preclinical and translational studies in osteoporosis research and the goat to a lesser extent. Recently, the pathophysiological mechanism underlying induction of osteoporosis in glucocorticoid-treated ovariectomized aged sheep was clarified, being similar to what occurs in postmenopausal women with glucocorticoid-induced osteoporosis. It was also concluded that the receptor activator of NF-κB ligand was stimulated in the late progressive phase of the osteoporosis induced by steroids in sheep. The knowledge of the pathophysiological mechanisms at the cellular and molecular levels of the induction of osteoporosis in small ruminants, if identical to humans, will allow in the future, the use of these animal models with greater confidence in the preclinical and translational studies for osteoporosis research.

Tartrate-resistant acid phosphate as biomarker of bone turnover over the lifespan and different physiologic stages in sheep.

BACKGROUND: Currently, the best resources for assessment of bone tissue using imaging techniques are expensive and available in few medical facilities, thus serum or urinary bone turnover biomarkers could be useful as early indicators of prognosis. However, there is a wide range of variability in bone turnover markers due to several factors, such as different ages and metabolic stages, thus it is important to have as much data published on the subject as possible. The aim of this study was therefore to generate a reference range for alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) and validate the already published data. RESULTS: Serum alkaline phosphatase decreased with age, with statistical difference between the 1 month old and the other groups and between the over 8 years and the 6 months old groups. There was also a statistical difference in the ALP levels between the 3 to 5 years old gestation and lactation groups. For serum tartrate-resistant acid phosphatase, there was a statistical difference mainly between the 1 month old and the 6 months old, 6-8 years old, and above 8 years old groups. CONCLUSIONS: The results obtained could represent a useful tool for future studies using sheep as an animal model for orthopedic research. The different groups presented a wide variation of serum ALP and TRAP levels, however, these variations are entirely explained by known physiology. Therefore, this detailed study confirms the prediction that unexplained changes in these bone turnover markers do not occur during the lifespan of sheep.

Bone turnover markers in sheep and goat: A review of the scientific literature.

Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.

Fracture Characterization of Human Cortical Bone Under Mode I Loading.

A miniaturized version of the double cantilever beam (DCB) test is used to determine the fracture energy in human cortical bone under pure mode I loading. An equivalent crack length based data-reduction scheme is used with remarkable advantages relative to classical methods. Digital image correlation (DIC) technique is employed to determine crack opening displacement at the crack tip being correlated with the evolution of fracture energy. A method is presented to obtain the cohesive law (trapezoidal bilinear softening) mimicking the mechanical behavior observed in bone. Cohesive zone modeling (CZM) (finite-element method) was performed to validate the procedure showing excellent agreement.

Identification of Apple Fruit-Skin Constitutive Laws by Full-Field Methods Using Uniaxial Tensile Loading.

The protective and preservative role of apple skin in maintaining the integrity of the fruit is well-known, with its mechanical behaviour playing a pivotal role in determining fruit storage capacity. This study employs a combination of experimental and numerical methodologies, specifically utilising the digital image correlation (DIC) technique. A specially devised inverse strategy is applied to evaluate the mechanical behaviour of apple skin under uniaxial tensile loading. Three apple cultivars were tested in this work: Malus domestica Starking Delicious, Malus pumila Rennet, and Malus domestica Golden Delicious. Stress-strain curves were reconstructed, revealing distinct variations in the mechanical responses among these cultivars. Yeoh's hyperelastic model was fitted to the experimental data to identify the coefficients capable of reproducing the non-linear deformation. The results suggest that apple skin varies significantly in composition and structure among the tested cultivars, as evidenced by differences in elastic properties and non-linear behaviour. These differences can significantly affect how fruit is handled, stored, and transported. Thus, the insights resulting from this research enable the development of mathematical models based on the mechanical behaviour of apple tissue, constituting important data for improvements in the economics of the agri-food industry.

Bacterial nanocellulose as a simple and tailorable platform for controlled drug release.

In this study we present a proof of concept of a simple and straightforward approach for the development of a Bacterial Nanocellulose drug delivery system (BNC-DDS), envisioning the local delivery of immunomodulatory drugs to prevent foreign body reaction (FBR). Inspired by the self-adhesion behavior of BNC upon drying, we proposed a BNC laminate entrapping commercial crystalline drugs (dexamethasone-DEX and GW2580) in a sandwich system. The stability of the bilayer BNC-DDS was evidenced by the high interfacial energy of the bilayer films, 150 ± 11 and 88 ± 7 J/m2 respectively for 2 mm- and 10-mm thick films, corresponding to an increase of 7.5 and 4.4-fold comparatively to commercial tissue adhesives. In vitro release experiments unveiled the tunability of the bilayer BNC-DDS by showing extended drug release when thicker BNC membranes were used (from 16 to 47 days and from 35 to 132 days, for the bilayer-BNC entrapping DEX and GW2580, respectively). Mathematical modeling of the release data pointed to a diffusion-driven mechanism with non-fickian behavior. Overall, the results have demonstrated the potential of this simple approach for developing BNC-drug depots for localized and sustained release of therapeutic agents over adjustable timeframes.

The Influence of Hydroxyapatite Crystals on the Viscoelastic Behavior of Poly(vinyl alcohol) Braid Systems.

Composites of poly(vinyl alcohol) (PVA) in the shape of braids, in combination with crystals of hydroxyapatite (HAp), were analyzed to perceive the influence of this bioceramic on both the quasi-static and viscoelastic behavior under tensile loading. Analyses involving energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) allowed us to conclude that the production of a homogeneous layer of HAp on the braiding surface and the calcium/phosphate atomic ratio were comparable to those of natural bone. The maximum degradation temperature established by thermogravimetric analysis (TGA) showed a modest decrease with the addition of HAp. By adding HAp to PVA braids, an increase in the glass transition temperature (Tg) is noticed, as demonstrated by dynamic mechanical analysis (DMA) and differential thermal analysis (DTA). The PVA/HAp composite braids' peaks were validated by Fourier transform infrared (FTIR) spectroscopy to be in good agreement with common PVA and HAp patterns. PVA/HAp braids, a solution often used in the textile industry, showed superior overall mechanical characteristics in monotonic tensile tests. Creep and relaxation testing showed that adding HAp to the eight and six-braided yarn architectures was beneficial. By exhibiting good mechanical performance and most likely increased biological qualities that accompany conventional care for bone applications in the fracture healing field, particularly multifragmentary ones, these arrangements can be applied as a fibrous fixation system.

Development of an Ultraviolet-C Irradiation Room in a Public Portuguese Hospital for Safe Re-Utilization of Personal Protective Respirators.

Almost two years have passed since COVID-19 was officially declared a pandemic by the World Health Organization. However, it still holds a tight grasp on the entire human population. Several variants of concern, one after another, have spread throughout the world. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant may become the fastest spreading virus in history. Therefore, it is more than evident that the use of personal protective equipment (PPE) will continue to play a pivotal role during the current pandemic. This work depicts an integrative approach attesting to the effectiveness of ultra-violet-C (UV-C) energy density for the sterilization of personal protective equipment, in particular FFP2 respirators used by the health care staff in intensive care units. It is increasingly clear that this approach should not be limited to health care units. Due to the record-breaking spreading rates of SARS-CoV-2, it is apparent that the use of PPE, in particular masks and respirators, will remain a critical tool to mitigate future pandemics. Therefore, similar UV-C disinfecting rooms should be considered for use within institutions and companies and even incorporated within household devices to avoid PPE shortages and, most importantly, to reduce environmental burdens.

Active Neutralizing Mats for Corrosive Chemical Storage.

Laboratories and industries that handle chemicals are ubiquitously prone to leakages. These may occur in storage rooms, cabinets or even in temporary locations, such as workbenches and shelves. A relevant number of these chemicals are corrosive, thus commercial products already exist to prevent material damage and injuries. One strategy consists of the use of absorbing mats, where few display neutralizing properties, and even less a controlled neutralization. Nevertheless, to the authors' knowledge, the commercially available neutralizing mats are solely dedicated to neutralizing acid or alkali solutions, never both. Therefore, this work describes the development and proof of a completely novel concept, where a dual component active mat (DCAM) is able to perform a controlled simultaneous neutralization of acid and alkali leakages by using microencapsulated active components. Moreover, its active components comprise food-grade ingredients, embedded in nonwoven polypropylene. The acid neutralizing mats contain sodium carbonate (Na2CO3) encapsulated in sodium alginate microcapsules (MC-ASC). Alkali neutralizing mats possess commercial encapsulated citric acid in hydrogenated palm oil (MIRCAP CT 85-H). A DCAM encompasses both MC-ASC and MIRCAP CT 85-H and was able to neutralize solutions up to 10% (v/v) of hydrochloric acid (HCl) and sodium hydroxide (NaOH). The efficacy of the neutralization was assessed by direct titration and using pH strip measurement tests to simulate the leakages. Due to the complexity of neutralization efficacy evaluation based solely on pH value, a thorough conductivity study was performed. DCAM reduced the conductivity of HCl and NaOH (1% and 2% (v/v)) in over 70%. The composites were characterized by scanning electron microscopy (SEM), differential calorimetry (DSC) and thermogravimetric analysis (TGA). The size of MC-ASC microcapsules ranged from 2 µm to 8 µm. Finally, all mat components displayed thermal stability above 150 °C.

Osteosynthesis Metal Plate System for Bone Fixation Using Bicortical Screws: Numerical-Experimental Characterization.

This study reports the numerical and experimental characterization of a standard immobilization system currently being used to treat simple oblique bone fractures of femoral diaphyses. The procedure focuses on the assessment of the mechanical behavior of a bone stabilized with a dynamic compression plate (DCP) in a neutralization function, associated to a lag screw, fastened with surgical screws. The non-linear behavior of cortical bone tissue was revealed through four-point bending tests, from which damage initiation and propagation occurred. Since screw loosening was visible during the loading process, damage parameters were measured experimentally in independent pull-out tests. A realistic numerical model of the DCP-femur setup was constructed, combining the evaluated damage parameters and contact pairs. A mixed-mode (I+II) trapezoidal damage law was employed to mimic the mechanical behavior of both the screw-bone interface and bone fractures. The numerical model replicated the global behavior observed experimentally, which was visible by the initial stiffness and the ability to preview the first loading peak, and bone crack satisfactorily.

Thermal, Mechanical and Chemical Analysis of Poly(vinyl alcohol) Multifilament and Braided Yarns.

Poly(vinyl alcohol) (PVA) in multifilament and braided yarns (BY) forms presents great potential for the design of numerous applications. However, such solutions fail to accomplish their requirements if the chemical and thermomechanical behaviour is not sufficiently known. Hence, a comprehensive characterisation of PVA multifilament and three BY architectures (6, 8, and 10 yarns) was performed involving the application of several techniques to evaluate the morphological, chemical, thermal, and mechanical features of those structures. Scanning electron microscopy (SEM) was used to reveal structural and morphological information. Differential thermal analysis (DTA) pointed out the glass transition temperature of PVA at 76 °C and the corresponding crystalline melting point at 210 °C. PVA BY exhibited higher tensile strength under monotonic quasi-static loading in comparison to their multifilament forms. Creep tests demonstrated that 6BY structures present the most deformable behaviour, while 8BY structures are the least deformable. Relaxation tests showed that 8BY architecture presents a more expressive variation of tensile stress, while 10BY offered the least. Dynamic mechanical analysis (DMA) revealed storage and loss moduli curves with similar transition peaks for the tested structures, except for the 10BY. Storage modulus is always four to six times higher than the loss modulus.

Shaved Cartilage Gel Versus Diced Cartilage on Final Dorsal Camouflage: Prospective Study of 200 Patients.

Importance: Diced cartilage (DC) is a reported technique that has been used for dorsal camouflage after reduction rhinoplasty. Nevertheless, there are certain issues regarding its use on nasal dorsum, especially its variable resorption rate and risk of graft distortion or migration, especially in thin-skinned patients. Recently, regenerative medicine protocols have been used to overcome drawbacks of methods based on DC. Thus, cartilage embedded in platelet-rich fibrin (PRF) has been described as a promising and reliable alternative to existing procedures. Objective: To compare long-term aesthetic outcomes of two different techniques for dorsal camouflage: DC versus shaved cartilage plus platelet-rich fibrin (SC+PRF)-shaved cartilage gel. Design, Setting, and Participants: This is a prospective, interventional, and longitudinal study at an academic tertiary medical center. Participants were 200 consecutive patients undergoing primary reduction rhinoplasty by spare roof technique (SRT) or component dorsal reduction (CDR). Materials and Methods: The inclusion criteria were primary rhinoplasty, in Caucasian patients with dorsal hump, and camouflage of the dorsum by DC or SC+PRF. Exclusion criteria were ≤18 years of age, revision rhinoplasty and reconstructive rhinoplasty for neoplasic or severe traumatic nasal deformities. The "Utrecht Questionnaire for outcome assessment in aesthetic rhinoplasty" was used. Patients answered it before and after surgery (3 and 12 months after). Results: The study population included 200 patients divided into two groups considering the type of dorsal camouflage: DC (n = 132) and shaved cartilage gel (n = 68). The mean age at the time of surgery was 35.44 years (standard deviation ±9.78) and the study population included 130 females (65.0%) and 70 males (35.0%). Regarding aesthetic outcomes, analyses of postoperative means showed a significant improvement, in both groups, over time. However, self-assessment, based on the visual analogue scale (VAS), at 12 months postsurgery, was higher for patients with SC+PRF than with DC (p = 0.004). Twelve months after surgery, patients with thin skin had better aesthetic outcome with SC+PRF than with DC (p = 0.001). For both reduction rhinoplasty techniques, aesthetic outcomes, based on the VAS at 12 months after surgery, were significantly better for patients with SC+PRF (SRT: p = 0.016; CDR: p = 0.004). For both rhinoplasty approaches, either open or closed, aesthetic outcomes, based on the VAS at 12 months after surgery, were significantly better for patients with SC+PRF (closed approach: p = 0.046; open approach: p = 0.017). Conclusions: SC+PRF provides better long-term aesthetic outcomes, not only for thin-skinned patients, but also for patients who had undergone rhinoplasty by a structured or preservation technique, or by an open or closed approach, for dorsal hump reduction.

Middle Vault Changes After Humpectomy by Spare Roof Technique Versus Component Dorsal Hump Reduction.

Objectives: To compare the effect of two different humpectomy techniques in the internal nasal valve (INV) angle in human anatomic specimens. Methods: Seven human anatomic specimens (14 heminoses) were included. A strip of subdorsal septal cartilage was removed and, in each nose, the right side of the middle roof lied intact over and was sutured to the septal cartilage (spare roof technique [SRT]), whereas in the left side the upper lateral cartilage was folded and sutured to the septal cartilage (component dorsal hump reduction [CDHR]). The INV angle was measured pre- and postoperatively. Results: Mean age of the specimens was 69.86 (60-80) years. Five were female. CDHR resulted in a mean change of +1.71 ± 3.12° (p = 0.197), +0.62 ± 6.89° (p = 0.817) and +6.97 ± 6.84° (p = 0.036) after resection of 2, 4, and 6 mm of septal cartilage, respectively. SRT resulted in a mean change of +1.27 ± 2.37° (p = 0.207), +6.89 ± 1.19° (p < 0.001), and +12.55 ± 1.79° (p < 0.001) after resection of 2, 4, and 6 mm of septal cartilage, respectively. In SRT, the amount of septal cartilage resection presented a significant correlation with change in INV angle (r = 0.813, p < 0.001). Conclusions: In this human anatomic study, SRT significantly increased INV angle.

Thermo-Mechanical Behaviour of Human Nasal Cartilage.

The aim of this study was to undergo a comprehensive analysis of the thermo-mechanical properties of nasal cartilages for the future design of a composite polymeric material to be used in human nose reconstruction surgery. A thermal and dynamic mechanical analysis (DMA) in tension and compression modes within the ranges 1 to 20 Hz and 30 °C to 250 °C was performed on human nasal cartilage. Differential scanning calorimetry (DSC), as well as characterization of the nasal septum (NS), upper lateral cartilages (ULC), and lower lateral cartilages (LLC) reveals the different nature of the binding water inside the studied specimens. Three peaks at 60-80 °C, 100-130 °C, and 200 °C were attributed to melting of the crystalline region of collagen matrix, water evaporation, and the strongly bound non-interstitial water in the cartilage and composite specimens, respectively. Thermogravimetric analysis (TGA) showed that the degradation of cartilage, composite, and subcutaneous tissue of the NS, ULC, and LLC take place in three thermal events (~37 °C, ~189 °C, and ~290 °C) showing that cartilage releases more water and more rapidly than the subcutaneous tissue. The water content of nasal cartilage was estimated to be 42 wt %. The results of the DMA analyses demonstrated that tensile mode is ruled by flow-independent behaviour produced by the time-dependent deformability of the solid cartilage matrix that is strongly frequency-dependent, showing an unstable crystalline region between 80-180 °C, an amorphous region at around 120 °C, and a clear glass transition point at 200 °C (780 kJ/mol). Instead, the unconfined compressive mode is clearly ruled by a flow-dependent process caused by the frictional force of the interstitial fluid that flows within the cartilage matrix resulting in higher stiffness (from 12 MPa at 1 Hz to 16 MPa at 20 Hz in storage modulus). The outcomes of this study will support the development of an artificial material to mimic the thermo-mechanical behaviour of the natural cartilage of the human nose.

Spare Roof Technique: A New Technique for Hump Removal-The Step-by-Step Guide.

Humpectomy is one of the most common steps in reduction rhinoplasty among Caucasian patients. The most widespread procedures to address hump removal are both the "en bloc humpectomy" (with reconstruction of the middle third with spreader grafts) and the "split hump technique" (with confection of spreader flaps). The spare roof technique, for rhinoplasty reduction, has been developed over the past 4 years. In this technique, the upper lateral cartilages are completely preserved-even the hidden part under the caudal aspect of the nasal bones. It consists of five main steps: step 1, the upper lateral cartilages are released from the dorsal aspect of the nasal septum; step 2, a 1-mm strip of the dorsal septum is taken in each movement as required; step 3, ostectomy of the caudal aspect of nasal bones, keeping the upper lateral cartilages intact and releasing the "lateral" (left and right) pyriform aperture ligament; step 4, classic medial and lateral osteotomies (closing the open bony roof); and step 5, suturing the upper lateral cartilages to the dorsal septum and thus avoiding the natural spring effect. The outcomes of the first 100 patients have been validated by a prospective, interventional, and longitudinal study performed on patients undergoing primary rhinoplasty by means of the spare roof technique. This study confirms that the spare roof technique significantly improved patient quality of life regarding nose function and appearance. It is a reliable technique that can help deliver consistently good results in Caucasian and Mediterranean patients with a dorsal hump seeking rhinoplasty.

Bone turnover markers in sheep and goat: A review of the scientific literature

ABSTRACT Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.