Metacarpal Research Articles

Mapping wrist motion: 3D CT analysis after scapholunate ligament transection.

The injury of the scapholunate (SL) ligament is common in wrist traumas leading to pain and reduced wrist function. The wrist's unique joint design and possible underlying theories as the carpal row theory were subject to earlier investigations studying wrist kinematics. Nevertheless, a comprehensive understanding of how SL ligament injuries affect wrist biomechanics is still lacking. Through a quantitative analysis of carpal bone motion patterns, we evaluated the impact on wrist kinematics occurring after SL ligament injury. We conducted a study using computer tomography imaging to analyse wrist kinematics after SL ligament transection in 21 fresh-frozen anatomical specimens. The collected data were then transformed into 3D models, employing both standardized global and object coordinate systems. The study encompassed the evaluation of rotation and translation for each individual carpal bone, as well as the ulna, and all metacarpal bones in reference to the radius. The study showed a significant increase in rotation towards palmar (p < 0.01), particularly notable for the scaphoid, following transection of the SL ligament during palmar flexion. Ulnar deviation did not significantly affect rotation or translation, and radial deviation also showed no significant changes in rotation or translation. The study highlights the significance of the SL ligament in wrist kinematics, revealing that SL ligament tears lead to changes in wrist motion. While we observed significant rotational changes for the scaphoid, other carpal bones showed less pronounced alterations, emphasizing the complexity of wrist biomechanics.

Congenital and Traumatic Conditions of the Pediatric Hand: Overview for the Radiologist.

Alignment, longitudinal growth, and function of the musculoskeletal unit of the pediatric hand is complex due to the combination of open growth plates, ossification variations, and their relationship with finger tendinous and ligamentous attachments. This review presents the basics of normal development, acquired and congenital variations, and traumatic conditions of the pediatric hand from the perspective of the pediatric musculoskeletal radiologist and hand surgeon. This multimodality imaging article focuses on non-oncologic and non-rheumatologic conditions of the pediatric hand, inclusive of fingers, thumb, and metacarpal bones.

The Figure-of-Eight Ligament Reconstruction in Thumb Carpometacarpal Instability: Surgical Technique and Clinical Outcomes

This study reviewed the results of the figure-of-eight ligament reconstruction, a technique used in the surgical management of thumb carpometacarpal (CMC) instability. This technique establishes joint stability through forces originating within the CMC joint, providing volar and dorsal support. We evaluated the outcomes of 15 patients with nontraumatic, nonarthritic thumb CMC instability treated with the figure-of-eight ligament reconstruction technique. This technique involves routing a graft of the palmaris longus tendon through the base of the first metacarpal and trapezium bone in a figure-of-eight fashion. Preoperative visual analog scale (0-100) for pain and Michigan Hand Outcomes Questionnaire total scores were compared with 3- and 12-month postoperative scores. Secondary outcomes included strength, range of motion, patient satisfaction, return to work, and complications. A significant improvement between intake and 12 months after surgery was observed for both Michigan Hand Outcomes Questionnaire total scores (53, SD 3 vs 70, SD 4) and visual analog scale pain scores (63, SD 4 vs 36, SD 7). Additionally, after surgery, restored thumb CMC joint stability was reported for all patients. Strength and range of motion improved between intake and 12 months after surgery. The median return to work was 6 weeks. Nine (60%) patients rated their satisfaction as "excellent" or "good," and 11 (73%) patients said that they would undergo the surgery again. The figure-of-eight ligament reconstruction significantly improves pain and function in patients with thumb CMC instability while restoring joint stability and preserving range of motion, making it a suitable technique. Therapeutic IV.

Study on Fixation Methods for Metacarpal Bone Fracture

Introduction with Objective: The aim of the present study was to assess the fixation methods for metacarpal bone fracture. Materials and Methods: A prospective observational study was conducted from February 2019 to January 2020 among 29 metacarpal bone fracture patients attending at orthopedic surgery department, Chittagong Medical College Hospital, Chittagong after obtaining requisite consent from the patient. Data were collected through the assessment and X-ray report of patients in the orthopedic surgery Department. The collected data were entered into the computer and analyzed by using SPSS (version 20.1) to assess the fixation methods for metacarpal bone fracture. Results: Most of the study population (89.7%) was in 18-40 years of age group. The mean age of the patients was 33.14 ± 11.895 years (range: 18-70 years). Service was the mostly occurring occupation among the patients (35%) and worker were 31%. In our study transverse fracture was 51.7% and oblique fracture was 41.4%. In case of method of fixation, maximum (65.5%) patient’s fixations were done by mini plate, 31% were by K-wire and 3.4% were by both K-wire &amp; lag screw. In case of number of metacarpal bone involvement, 1 bone was involved in maximum (75.9%), 2 bone were involved in 17.2% and 3 bone were involved in 6.9% patients. Conclusion: Closed or minimally invasive fixation with K-wire, mini plates and screws are safe methods and can be performed with minimal complications. Maximum (65.5%) patient’s fixations were done by mini plate. Medicine Today 2024, Vol.36 (2): 87-89

Sex estimation using Magnetic Resonance Imaging measurements of hand and foot in Egyptian population

BackgroundThe identification of skeletal remains begins with a sex evaluation since other biological profile elements, such as size and age, are sex-specific. The pelvis is the favored element for sex assessment since it is very sexually dimorphic.Aim of the studyDelivering hand and foot bones sex estimate criteria for Egyptian population identification was the goal of this work.Subject and methodsEighty-two Egyptian adult subjects (41 males and 41 females) aged ≥ 21 years old were subjected to MRI scan on the right hand and foot to assess 9 measurements: hand length, hand width, four measurements of middle metacarpal bone (length, breadth, head breadth and base breadth), first metatarsal bone length, first metatarsal bone width and (first metatarsal bone length x first metatarsal bone width).ResultsAll the measured parameters in the right hand and foot were higher in males than females. First metatarsal bone length x first metatarsal bone width in the foot and middle metacarpal bone breadth in the hand were the most sexually dimorphic parameters, with accuracy of 86.6 percent and 84.1 percent, respectively. In stepwise discriminant analysis, three of nine measurements were selected: First metatarsal bone length x first metatarsal bone width, middle metacarpal bone breadth and hand width for the sex prediction equation in the Egyptian population, with a cross-validated sex classification accuracy of 90.2%.ConclusionSex can be assessed from hand and foot metric parameters measured by MRI with high accuracy.

Radiomorphometric analysis of the metapodial bones in the Scottish fold cats.

Scottish Fold cats (Felis catus, Linnaeus 1758) are one of the most well-known and popular cat breeds in the world, characterized by their folded ears attached to the head. Very frequently, cats fall prey of different trauma and accidents that can cause bone fractures especially in the metapodial bones. The method of radiometry is used in veterinary practice to visualize and measure different parts of the animal skeleton. The aim of this study was to assess the linear parameters derived from radiographic images of the metacarpals and metatarsals in Scottish Fold cats and additionally detecting potential sexual dimorphism. Radiographic images of 24 adult Scottish Fold cats (12 male and 12 females) of different ages and weights were analysed. Six linear measurements of the metapodial bones were evaluated to investigate any differences between the sexes. The linear radiometric measurements of the five metacarpals (MC1-5) and the four metatarsals (MT2-5) bones were larger in male metapodial bones than that of female cats. The maximum length (Ml) of the MC1 and MC2 was statistically different between sex, respectively, (p = 0.001) and (p = 0.05). The others metacarpal bones were different in mostly all linear parameters but not statistically significant. The most significant differences between sexes were observed in the parameter of width proximal end (Wp) of MC1-3 (p = 0.001) and MC4 (p = 0.05). More statistical different was MT2 and less MT3. The linear parameter of Bd of the MT4 was the most different statistically between sex (p = 0.001). The results of the study will be useful in function of comparative anatomy, in veterinary clinical practice, in zoo archaeology and in the veterinary forensic investigation.

Presentation of melorheostosis with pain and swelling of the hand bones: A case report and review of literature

Melorheostosis is a rare disease also known as Leri disease with about 400 cases in the world with unknown etiology although relations with mitogen-activated protein kinase 1 gene and LEM domain-containing protein 3 gene mutations are described. We presented a case of melorheostosis referred to the rheumatology clinic with pain and swelling in the middle phalanx of the index finger and second metacarpal bone of right hand. X-ray of the hand showed a hyperdense lesions in the hand bones with obliteration of the medulla. Right hand magnetic resonance imaging showed signal loss of bone marrow in the second metacarpal bone and middle phalanx of the index finger along with severe periosteal edema. Bone biopsy confirmed melorheostosis.

Effectiveness of an X-ray shielding sheet with lower shielding ability to enable both bone mineral density determination and morphological diagnosis

Bone Mineral Density (BMD) can be determined by applying the Digital Image Processing (DIP) method using medical X-ray diagnosis. Although only the second metacarpal bone is analyzed in this approach, other parts of the body are exposed to X-ray radiation. We here propose a novel procedure in which parts of the hand surrounding the area of interest are shielded with an X-ray shielding sheet having low shielding performance. In our procedure, the main diagnostic area is not shielded, and other areas are covered with an X-ray shielding sheet with a low shielding performance. The sheet was fabricated by embedding Bi2O3 particles in resin sheet. We assessed the clinical performance of this method using three types of hand phantoms and conventional diagnostic X-ray equipment. The dose reduction for the entire hand region was evaluated by the Dose Area Product (DAPHand), which was measured with a small dosimeter, and the hand area was determined from the X-ray image. The X-ray image of the second metacarpal bone is affected by the contribution of X-rays that penetrate the object of interest and are scattered in other areas of the hand. Because our X-ray shielding sheet suppressed the generation of scattered X-rays, the pixel value of the second metacarpal bone and corresponding BMD value are varied. To address this issue, we developed a correction algorithm. We found that the X-ray shields with Dose Reduction Factor (DRF) values of 40–60% were appropriate for our methodology. Our method was estimated to have a percentage uncertainty of approximately 5% for the derivation of BMD values. Morphological information of the hand and bones could thus be clearly observed. We verified that both morphological diagnosis and quantitative determination of BMD are possible when DIP procedure is conducted using our shield.

Ligament Suspensionplasty With Suture Tape Augmentation​ for Basal Thumb Arthritis.

Thumb carpometacarpal arthritis is common with aging, more common in women than men, and usually occurs after age 40. If a patient fails conservative treatments such as splinting, medications, and corticosteroid injections, then surgical intervention may be appropriate. Currently, there is no consensus on the best surgical treatment. By limiting metacarpal subsidence, ligament suspensionplasty with suture tape augmentation offers great pain relief, excellent functional outcomes, and limited postoperative immobilization. With this technique, trapeziectomy is first performed. A portion of the abductor pollicis longus tendon is resected and loaded onto the SwiveLock anchor using 4-0 FiberLoop, in addition to suture tape. The prepared graft and tape construct is anchored into the lateral first metacarpal (MC) base and index metacarpal base. After surgery, patients are put in a short arm thumb spica splint, interphalangeal (IP) joints free. Active motion is initiated at the first postoperative visit, usually within 1 week. All patients who had thumb arthritis treated with carpometacarpal suspensionplasty and suture tape augmentation between 2015 and 2022 by a single hand surgeon at our institution were queried. A total of 110 patients were invited to take part in this study, and 61 patients consented and were included in this study. Mean last in-office follow up was at 7.5±4.0 months, which showed significant improvements in pinch strength (P=0.011). A survey taken at a mean 2.8±1.3 years (range: 0.5 to 5.2y) after surgery reports a postoperative DASH score of 7.3±7.7 (range: 0 to 23.3), and VAS pain score of 0.7±1.1 (range: 0 to 5).

An Automated Assessment Method for Chronic Kidney Disease–Mineral and Bone Disorder (CKD-MBD) Utilizing Metacarpal Cortical Percentage

Chronic kidney disease–mineral and bone disorder (CKD-MBD) frequently occurs in hemodialysis patients and is a common cause of osteoporosis. Regular dual-energy X-ray absorptiometry (DXA) scans are used to monitor these patients, but frequent, cost-effective, and low-dose alternatives are needed. This study proposes an automatic CKD-MBD assessment model using histogram equalization and a squeeze-and-excitation block-based residual U-Net (SER-U-Net) with hand diagnostic radiography for preliminary classification. The process involves enhancing image contrast with histogram equalization, extracting features with the SE-ResNet model, and segmenting metacarpal bones using U-Net. Ultimately, a correlation analysis is carried out between the calculated dual metacarpal cortical percentage (dMCP) and DXA T-scores. The model’s performance was validated by analyzing clinical data from 30 individuals, achieving a 93.33% accuracy in classifying bone density compared to DXA results. This automated method provides a rapid, effective tool for CKD-MBD assessment in clinical settings.

Evaluation of Conservative Treatment or Osteosynthesis in the Treatment of Cats with Metacarpal and/or Metatarsal Fractures: A Retrospective Study

Aim: This study aims to assess the merits, drawbacks, and postoperative outcomes associated with conservative treatment and osteosynthesis methods employed in managing metacarpal (MC) and/or metatarsal (MT) bone fractures resulting from trauma in cats. Materials and Methods: The research encompassed a sample of fifty-two cats of varying breeds, genders, and ages, all presenting with metacarpal and/or metatarsal bone fractures between 2022 and 2023. Conservative treatment was administered in 46 cases, while osteosynthesis was applied in the remaining 6 cases. Results: In the group treated conservatively, 29 cases (63.04%) exhibited no signs of lameness at the 6-week examination, indicating a successful recovery with unimpeded mobility. In contrast, mild lameness was observed in the remaining cases (36.96%) at the 6-week check-up. Upon reassessment at the 12-month examination, 43 cases (93.47%) demonstrated unimpeded walking, with only 3 cases (6.53%) experiencing occasional mild lameness. Conversely, 2 cases (33.3%) showed a complication-free recovery among the cats undergoing osteosynthesis, while postoperative issues emerged in 4 cases (66.6%). In one complication-free case (50%), mild lameness was noted at the 6-week examination, and in the other case (50%), occasional mild lameness was observed. Importantly, all cases exhibited uneventful walking during the 12-month assessment. Conclusion: Conservative treatment proves to yield favorable outcomes in cats, both independently and when osteosynthesis applications fall short. However, the limited number of surgical cases examined in the study constrains the findings' generalizability

Skeletal malformation in growing milk sheep.

Two six-month old female Lacaune lambs with severe skeletal malformations of both front limbs were presented to the Department of Farm Animals, University of Zurich. The clinical examination showed alert animals with a high body weight and body condition score as well as a valgus deformation without pain or swelling. Radiographic examination showed severe irregularities in the epiphysial plate of the metacarpal bones in both lambs. Delayed growth in the lateral aspects of the physis was evident and resulted in valgus deformation. Nutritional causes were considered as the main reason for this presentation and a nutritional consultation was performed by the Institute of Animal Nutrition and Dietetics, University of Zurich. The estimated energy intake of these lambs was 65 % higher than the recommended maximum for growing sheep and the estimated vitamin D content of the diet was 71 % below the recommended allowance. Both animals were euthanized, and peripheral quantitative computed tomography (pQCT) was performed postmortem to measure total bone mineral density (BMD), trabecular bone mineral density (tBMD) and cortical bone mineral density (cBMD) of the left and right metatarsal bone of both animals. The BMD and the tBMD at 10 % of bone length were below the reference values and the BMD at 50 % was above the reference values. In addition, postmortem examination revealed a Salter-Harris-Typ-1 facture in the right caput humeri of one lamb. Histological evaluation showed defects in the articular cartilage with an eburnation in the metacarpal region and a disrupted area of columnar cartilage. This case report supports the fact that a high dietary energy intake leads to damage to the cartilage and the epiphyseal zone in sheep. In addition, insufficient dietary vitamin D intake contributed to the incomplete bone mineralization, as well as delayed growth and skeletal malformation.

A New Biosynthetic 6-Phytase Added at 500 Phytase Unit/kg Diet Improves Growth Performance, Bone Mineralization, and Nutrient Digestibility and Retention in Weaned Piglets and Growing-Finishing Pigs.

Two experiments were performed to evaluate the effect of a biosynthetic 6-phytase added at 500 phytase unit (FTU)/kg diet on growth performance, bone mineralization, and nutrient digestibility and retention in weaned piglets and growing-finishing pigs. Experiments were performed on 90 weaned male and female piglets with an average initial body weight (BW) at 7.7 ± 0.73 kg, 26 days of age) and 300 male and female growing pigs (initial BW: 21.0 ± 3.44 kg) for 43 and 98 days in experiments 1 and 2, respectively. In each experiment, the animals were assigned to one of three treatments according to a randomized complete block design. The treatments consisted of a positive-control (PC) diet formulated to meet nutrient requirements; a negative-control (NC) diet reduced similarly in calcium (Ca) and digestible P by 0.15 and 0.12% points in phases 1 and 2, respectively, in piglets and by 0.14, 0.11, and 0.10% points, respectively, in phases 1, 2, and 3 in growing-finishing pigs, compared with PC diet; and a NC diet supplemented with the new 6-phytase at 500 FTU/kg diet (PHY). The dietary P and Ca depletion reduced (p < 0.05) the final BW (-11.9%; -7.8%,), average daily gain (ADG, -17.8%; -10.1%), average daily feed intake (ADFI, -9.9%; -6.0%), gain-to-feed (G:F) ratio (-8.9%; -4.6%), and apparent total tract digestibility (ATTD) of P (-7.7% points; -6.7% points) in nursery piglets and growing pigs, respectively. It also decreased (p < 0.001) P and Ca retention by 6.1 and 9.4% points, respectively, in nursery pigs and ash, P, and Ca contents in metacarpal bones by 18.4, 18.4, and 16.8%, respectively, in growing pigs. Compared to animals fed the NC diet, phytase supplementation improved (p < 0.001) the final BW (+7.7%; +11.3%), ADG (+12.5%; +15.0%), G:F ratio (+8.4%; +5.8%), ATTD of Ca (+10.8% points; +7.2% points), and ATTD of P (+18.7% points; +16.6% points) in weaned piglets and growing pigs, respectively. In addition, phytase also increased (p < 0.001) P and Ca retention by 6.1 and 9.4% points, respectively, in nursery pigs and ash, P, and Ca contents in metacarpal bones by 17.7, 15.0, and 15.2%, respectively, in growing pigs. The final BW, ADG, G:F ratio, and bone traits in animals fed the NC diet supplemented with phytase were comparable to animals fed the PC diet. This finding indicates the ability of this novel biosynthetic phytase to restore performance and bone mineralization by improving the availability of P and Ca in piglets and growing pigs fed P- and Ca-deficient diets.

Magnetic Resonance Imaging, Computed Tomographic and Radiographic Findings in the Metacarpophalangeal Joints of 31 Warmblood Showjumpers in Full Work and Competing Regularly.

There is a limited description of magnetic resonance imaging (MRI) and no information on computed tomographic (CT) findings in the fetlock of non-lame, non-racing sports horses. This study aimed to document comparative CT, MRI and radiographic findings in the metacarpophalangeal joints of showjumpers in full work. Clinical and gait assessments, low-field MRI, fan-beam CT and radiographic examinations of both metacarpophalangeal joints were performed on 31 showjumpers. Images were analysed descriptively. In most limbs (53/62, 85.5%), there were CT and MRI changes consistent with densification in the sagittal ridge and/or condyles of the third metacarpal bone (McIII). Hypoattenuation (subchondral bone resorption) was seen in CT reconstructions in the metacarpal condyle dorsoproximally (n = 2) and dorsodistally (n = 1), in the sagittal groove (n = 2) and medial fovea (n = 1) of the proximal phalanx. The McIII resorptive lesions were detected on MR images but not the proximal phalanx lesions. None were identified on radiographs. In conclusion, MRI and CT abnormalities previously associated with lameness were seen in the front fetlocks of showjumpers without relevant lameness. Densification in the sagittal ridge and the metacarpal condyles likely reflects an adaptive change to exercise. Subchondral bone resorption may indicate an early stage of disease; follow-up information is needed to establish its clinical significance.

46 Efficacy of a biosynthetic 6-phytase depending on basal diet composition in weaning piglets

Abstract A study was conducted to evaluate the efficacy of biosynthetic 6-phytase depending on basal diet composition on growth performance and bone mineralization in weaned piglets. A total of 192 male weaned piglets with initial body weight (BW) of 8.47 ± 0.70 kg (at 33 d of age), distributed in a randomized block design with a 3 x 2 factorial arrangement of treatments. Three basal diet compositions (BD1: adequate in energy and nutrients with phytic P (PP) = 0.23%; BD2 = BD1 minus 70 kcal NE/kg, 0.15% points similarly in digestible P (dig.P) and calcium (Ca) with PP = 0.23%; and BD3 = BD1 minus 70 kcal NE/kg, 0.15% points similarly in dig.P and Ca with PP = 0.29%) and two phytase inclusion (Rovabio PhyPlus; 0 or 1,000 FTU/kg diet) were used in this experiment. The corn-soybean meal-based diets were fed into 2 phases: post-weaning 1 and 2 from 1 to 14 and 15 to 42 d, respectively. Body weight and feed intake were measured at the end of each phase, and average daily gain (ADG), average daily feed intake (ADFI) and feed to gain ratio (F:G) were calculated for the whole experimental period. At the end of the study, all piglets from 16 pens per treatment (n = 32 piglets/treatment) were euthanized and the metacarpi bones were collected for bone ash and P content determinations. There were significant interactions (P &amp;lt; 0.05) between basal diet composition and phytase inclusion on final BW, ADG, F:G, ash and P contents in metacarpal bones of piglets. Compared with unsupplemented diet, the addition of phytase in both nutrient-reduced diets improved final BW, ADG, F:G, ash and P contents in bones, while no improvements (P &amp;gt; 0.05) were observed on these parameters by phytase supplementation in adequate-nutrient diet. There was no significant interaction (P &amp;gt; 0.05) between basal diet composition and phytase inclusion on ADFI. Reduction in nutrients without (BD2) or with increasing dietary PP level (BD3) decreased (P = 0.004) ADFI, compared with adequate-nutrient diet. However, addition of biosynthetic 6-phytase improved (P = 0.03) ADFI by 5.3% compared with unsupplemented diets. The results of the present study highlight that adding biosynthetic 6-phytase to low energy and nutrient diets was more effective compared with the effects in an adequate-nutrient diet in weaned piglets.

PSI-16 Effect of HiPhorius phytase on finishing pig growth performance and bone mineralization with the use of two diet formulation strategies

Abstract Two experiments were conducted to determine the effect of HiPhorius (dsm-firmenich, Parsippany, NJ) phytase on finishing pig growth performance, serum chemistry, bone mineralization, and carcass characteristics. In Exp. 1, 1,161 pigs (PIC 337 × 1050, initially 36.7 ± 0.48 kg) were used in a 105-d trial. There were 27 pigs per pen and 10 or 11 replications per treatment. Treatments consisted of: 1) Control diet with no added phytase and formulated to NRC (2012) requirement estimates for standardized total tract digestible (STTD) P; 2) 600 FYT/kg added phytase formulated to the same STTD P as the control diet considering a release of 0.13% STTD P and 0.095% STTD Ca; 3) 1,000 FYT/kg added phytase formulated to the same STTD P as the control diet considering release of 0.16% STTD P and 0.107% STTD Ca, and 4) high STTD P (no phytase; approximately 22% above NRC requirement estimates). All diets were formulated to a 1.30:1 STTD Ca:STTD P ratio, but analysis suggested all phases were greater than the formulated target. Overall, pigs fed NRC (2012) or increased STTD P had increased average daily gain (ADG) and hot carcass weight (HCW; P &amp;lt; 0.05) compared with pigs fed the treatments with added phytase. Pigs fed NRC (2012) STTD P had greater (P &amp;lt; 0.05) gain to feed ratio (G:F) compared with those with 1,000 FYT/kg with other treatments intermediate. In Exp. 2, 1,160 pigs (PIC 337 × 1050, initially 75.9 ± 1.32 kg) were used in a 58-d trial. There were 27 pigs per pen and 11 replications per treatment. Treatments were the same as in Exp.1 except diets were formulated to the same total Ca:P ratio [1.15:1 from 75 to 100 kg and 1.12:1 from 100 to 136 kg body weight (BW)] without a STTD Ca release consideration from phytase; however, diets analyzed with a wider Ca:P compared with the expected value (Table 1). Overall, there were no differences in ADG, average daily feed intake (ADFI) or G:F among treatments (P &amp;gt; 0.10). For pigs fed NRC or increased STTD P, there was an increase (P &amp;lt; 0.05) in metacarpal bone density, and a tendency for increased (P &amp;lt; 0.10) bone ash weight and percentage bone ash compared with pigs fed treatments containing phytase. In conclusion, regardless of diet formulation strategy, pigs fed diets with phytase had decreased growth performance (Exp.1) and bone mineralization (Exp.2), which was unexpected and could be a result of the nutrient release values attributed to the phytase being overestimated, not enough phytate-bound P that is phytase-sensitive present in the diets, or too wide of a Ca:P ratio leading to reduced phytase activity in the analyzed diet samples compared with the intended ratio based on diet formulation.

Biomechanical analysis of plate versus K-wire fixation for metacarpal shaft fractures with wedge-shaped bone defects

BackgroundMetacarpal shaft fracture is a common type of hand fracture. Numerous studies have explored fixing transverse fractures in the midshaft of the metacarpal bone. However, this section of the metacarpal bone is often susceptible to high-energy injury, resulting in comminuted fracture or bone loss. In such cases, wedge-shaped bone defects can develop in the metacarpal shaft, increasing the difficulty of performing fracture fixation. Notably, the research on this type of fracture fixation is limited. This study compared the abilities of four fixation methods to fix metacarpal shaft fractures with wedge-shaped bone defects.MethodsIn total, 28 artificial metacarpal bones were used. To create wedge-shaped bone defects, an electric saw was used to create metacarpal shaft fractures at the midshaft of each bone. The artificial metacarpal bones were then divided into four groups for fixation. The bones in the first group were fixed with a dorsal locked plate (DP group), those in the second group were fixed with a volar locked plate (VP group), and those in the third group were fixed by combining dorsal and volar locked plates (DP + VP group), and those in the fourth group were fixed with two K-wires (2 K group). Cantilever bending tests were conducted using a material testing machine to measure yielding force and stiffness. The four groups’ fixation capabilities were then assessed through analysis of variance and Tukey’s test.ResultsThe DP + VP group (164.1±44.0 N) achieved a significantly higher yielding force relative to the 2 K group (50.7 ± 8.9 N); the DP group (13.6 ± 3.0 N) and VP group (12.3 ± 1.0 N) did not differ significantly in terms of yielding force, with both achieving lower yielding forces relative to the DP + VP group and 2 K group. The DP + VP group (19.8±6.3 N/mm) achieved the highest level of stiffness, and the other three groups did not differ significantly in terms of stiffness (2 K group, 5.4 ± 1.1 N/mm; DP group, 4.0 ± 0.9 N/mm; VP group, 3.9 ± 1.9 N/mm).ConclusionsThe fixation method involving the combined use of dorsal and volar locked plates (DP + VP group) resulted in optimal outcomes with respect to fixing metacarpal shaft fractures with volar wedge bone defects.

Effects of dietary phytase with or without multi-carbohydrase supplementation on growth performance, nutrient digestibility, and bone traits in nursery pigs

The aim was to determine the effects of supplementing increasing doses of phytase alone or in combination with a multi-carbohydrase blend to a phosphorus (P)-deficient diet for nursery pigs on growth performance, nutrient digestibility, and metacarpal bone characteristics. A total of 192 weaned pigs (7.7 ± 0.05 kg) were allotted to one of eight dietary treatments each with eight replicates in a randomized complete block design based on initial body weight. Fecal samples (days 18, 19, and 20) and metacarpal bones (day 21) were collected to determine apparent total tract digestibility (ATTD) of energy and nutrients and bone mineralization, respectively. During week 3 and overall period, increasing doses of phytase quadratically increased ( P &lt; 0.05) average daily gain. The ATTD of ash and P quadratically increased ( P &lt; 0.05) when doses of phytase increased. Phytase had quadratic ( P &lt; 0.05) effects by increasing fat-free dry weight, ash content, and P in metacarpal bone. In conclusion, increasing levels of phytase quadratically improved growth performance in week 2, nutrient digestibility, and bone traits of pigs fed a P-deficient diet. In general, however, there was no effect of multi-carbohydrase supplementation on growth performance and metacarpal characteristics in nursery pigs.

Subchondral bone fatigue injury in the parasagittal condylar grooves of the third metacarpal bone in thoroughbred racehorses elevates site-specific strain concentration

Condylar stress fracture of the distal end of the third metacarpal/metatarsal (MC3/MT3) bones is a major cause of Thoroughbred racehorse injury and euthanasia worldwide. Functional adaptation to exercise and fatigue damage lead to structural changes in the subchondral bone that include increased modeling (resulting in sclerotic bone tissue) and targeted remodeling repair (resulting in focal resorption spaces in the parasagittal groove). Whether these focal structural changes, as detectable by standing computed tomography (sCT), lead to elevated strain at the common site of condylar stress fracture has not been demonstrated. Therefore, the goal of the present study was to compare full-field three-dimensional (3D) strain on the distopalmar aspect of MC3 bone specimens with and without focal subchondral bone injury (SBI). Thirteen forelimb specimens were collected from racing Thoroughbreds for mechanical testing ex vivo and underwent sCT. Subsequently, full-field displacement and strain at the joint surface were determined using stereo digital image correlation. Strain concentration was observed in the parasagittal groove (PSG) of the loaded condyles, and those with SBI in the PSG showed higher strain rates in this region than control bones. PSG strain rate in condyles with PSG SBI was more sensitive to CT density distribution in comparison with condyles with no sCT-detectable injury. Findings from this study help to interpret structural changes in the subchondral bone due to fatigue damage and to assess risk of incipient stress fracture in a patient-specific manner.

Morphological and radiographic studies on the Manus region in the Arabian one-humped camel (Camelus dromedaries).

The study aims to analyse the normal anatomical and radiographical features of the Manus of the southern Aswanian-adapted Arabian one-humped camel, providing crucial data for diagnosing and treating various ailments. Our study was applied to 10 cadaver forelimbs of adult male one-humped camels (4-5 years old) for an explanation of the gross anatomy of the bones of the Manus region from under the carpal bones by using traditional techniques, including the gross anatomical, radiographic and x-ray (at the dorsopalmar and lateral planes) of the preparation of Manus bones. Our results showed that the large fused (third and fourth) metacarpal bones, in which the fusion extended along the entire length of the bone except at the distal end, diverged to form separate articulations with cross-ponding digits. As described in all ruminant species, especially the camel, there were two digits, and each digit consisted of three phalanges and two proximal sesamoid bones. Our radiographic x-ray data revealed that the complete radiopaque septum that completely divided the medullary cavity into two separate parts was clear from the dorsopalmar view, while the lateral view showed the proximal sesamoid bones that were placed over each other and located palmar to the head of the large metacarpal bone. In conclusion, our study reveals the adaptations of the Arabian one-humped camel to Egyptian conditions, aiding in the early diagnosis of lameness and digit problems and enabling veterinarians and camel owners to better address these issues, thereby improving the overall health and well-being of these animals.