In silico identification of new putative pathogenic variants in the NEU1 sialidase gene affecting enzyme function and subcellular localization

The NEU1 gene is the first identified member of the human sialidases, glycohydrolitic enzymes that remove the terminal sialic acid from oligosaccharide chains. Mutations in NEU1 gene are causative of sialidosis (MIM 256550), a severe lysosomal storage disorder showing autosomal recessive mode of inheritance. Sialidosis has been classified into two subtypes: sialidosis type I, a normomorphic, late-onset form, and sialidosis type II, a more severe neonatal or early-onset form. A total of 50 causative mutations are reported in HGMD database, most of which are missense variants. To further characterize the NEU1 gene and identify new functionally relevant protein isoforms, we decided to study its genetic variability in the human population using the data generated by two large sequencing projects: the 1000 Genomes Project (1000G) and the NHLBI GO Exome Sequencing Project (ESP). Together these two datasets comprise a cohort of 7595 sequenced individuals, making it possible to identify rare variants and dissect population specific ones. By integrating this approach with biochemical and cellular studies, we were able to identify new rare missense and frameshift alleles in NEU1 gene. Among the 9 candidate variants tested, only two resulted in significantly lower levels of sialidase activity (pC and c.700G>A. These two mutations give rise to the amino acid substitutions p.V217A and p.D234N, respectively. NEU1 variants including either of these two amino acid changes have 44% and 25% residual sialidase activity when compared to the wild-type enzyme, reduced protein levels and altered subcellular localization. Thus they may represent new, putative pathological mutations resulting in sialidosis type I. The in silico approach used in this study has enabled the identification of previously unknown NEU1 functional alleles that are widespread in the population and could be tested in future functional studies

Diagnostic value of whole body bone scan in horses

Scintigraphy is widely used in the assessment of musculoskeletal disorders and often it is considered as a screening tool in lame or poor performing horses. It is proved that nuclear scintigraphy is useful in highlighting the presence of lesions undetectable by clinical examination, in horses that do not respond to local analgesic blocks or with intermittent lameness[1]. Despite the usefulness of bone scan is proven, in a recent report, Quiney et al. observed that false-negative results predominate and may lead to missed diagnosis[2]. The aim of this study is to analyze the diagnostic usefulness of whole body bone scan in horses referred for lameness or poor performance. For this retrospective study, bone scans acquired at the Ospedale Veterinario Universitario di Lodi between July 2014 and February 2019 were reviewed. In the study have been included only horses that had a whole body bone scan. On the basis of the history, horses were classified as poor performing, for localized lameness or non-localized lameness. Scintigraphic findings were organized in five categories: definitive diagnosis, localization of the lameness, no findings related to the present clinical signs, findings of unlikely clinical significance and findings that need further investigations. A contingency table and a chi-squared test were used for the statistical analysis. One hundred and eighty horses underwent scintigraphy and 102 were included in the study; twenty-one horses were referred for lameness localized using diagnostic analgesia while in 44 horses the source of lameness was not identified. Thirty-seven horses had an history of poor performance. Statistical analysis highlighted that the only correlation between clinical history and scintigraphic findings was between horse referred for poor performance and findings of unlikely clinical significance (59,5% of horses with a poor performance diagnosis). A final diagnosis or localization of the source of pain were observed respectively in the 5.9% and in the 29.4% of horses. In 11 subjects (10.8%) were found increased radiopharmaceutical uptakes (IRU) of uncertain clinical significant that needed further investigations using analgesic blocks. In the 20% of cases, all referred for lameness, no findings related to the present clinical signs were found. In order to increase the capability of bone scintigraphy, it is mandatory to consider that the sensitivity and specificity are higher in specific regions[2] and the interpretation of the relevance of IRU must be based on detailed clinical examination. In conclusion, we confirm that whole body bone scintigraphy should not be considered a diagnostic screening especially in poor performing horses and that localization of lameness can improve the possibility of a positive result. [1] Dyson S.J. Musculoskeletal scintigraphy of the equine athlete. Semin Nucl Med, 44:4-14, 2014. [2] Quiney L., Ireland J., Dyson S.J. Evaluation of the diagnostic accuracy of skeletal scintigraphy in lame and poorly performing sports horses. Vet Radiol Ultrasound, 59:477-489, 2018

XMM-Newton observation of the 5.25 ms transient millisecond pulsar XTE J1807-294 in outburst

We report on the results obtained for the millisecond transient X-ray pulsar XTE J1807-294 in a 40 min orbital period system, based on an XMM-Newton ToO observation carried out during March 2003. The source was found at a luminosity level of about 2x10^36 erg/s in the 0.5-10 keV range (assuming a distance of 8 kpc). We confirm the presence of the 5.25 ms pulsations (after accounting for the orbital modulation) and find a pulsed fraction of 5.8% in the 0.3-10 keV band. The pulse shape in nearly sinusoidal. The spectral continuum of the source is well fitted by an absorbed Comptonization model plus a soft component. No emission or absorption lines have been detected in the 0.5-10 keV range with upper limits of 10-40 eV. The reported analysis represent the first detailed study of this source, the fourth belonging to the ultra-compact binary system class hosting an accreting neutron star.Comment: Accepted for publication in ApJ

Continuous rate infusion of dexmedetomidine vs subcutaneous administration in anaesthetized horses undergoing MRI examination

Up to 2005, dexmedetomidine use had not been reported in equine. Since then, several experimental and clinical studies have been published. The main reason for this increase relies on its beneficial pharmacological profile, including short half-life and rapid redistribution (1). The aim of the study is to compare the clinical effects and recovery quality after continuous rate infusion (CRI) or subcutaneous administration of dexmedetomidine in horses undergoing general anaesthesia. Fourteen horses scheduled for MRI examination were included. All horses were sedated with acepromazine 0.03 mg kg-1 intravenously (IV) and detomidine 10 \ub5g kg-1 (IV). Anaesthesia was induced with ketamine 3 mg kg-1 (IV) and diazepam 0.04 mg kg-1 (IV) and maintained with isofluorane in 60% oxygen; end-tidal isoflurane concentration was maintained between 1.3-1.4 %. Horses were randomly divided in two groups. Group \u201cDex CRI\u201d received dexmedetomidine intravenously at 1 \ub5g kg-1 hour-1, group \u201cDex SC\u201d received 2 \ub5g kg-1 of dexmedetomidine subcutaneously every 60 minutes. If nystagmus or incessant fighting against ventilator occurred, ketamine rescue at 0.1 mg kg-1 was given. In case of sudden movements, thiopental 0.5-1.0 mg kg-1 IV was given. Ringer\u2019s lactate was given at 3 mL kg-1 hour-1, dobutamine was administered IV and the rate adjusted to maintain MAP>70 mmHg. Controlled mechanical ventilation using intermittent positive pressure ventilation was adjusted to maintain arterial carbon dioxide partial pressure between 38-45 mmHg. Heart rate, invasive arterial blood pressure, arterial blood gases, total dose of dobutamine administered, ketamine rescue needed, urine production were recorded. Time required until extubation and time to attain sternal and standing position were noted. The main anaesthesiologist assessed recovery quality graded on a standard scoring 5-point scale with a score of 1 representing the best recovery (2). Mann-Whitney U test was applied for non-parametric data and T-test for parametric data (p 640.05). There was no statistically differences in physiological intra-anaesthetic parameters, in body weight (kg) (CRI 521\ub153; SC 506\ub176), age (years) (CRI 10.7\ub12.1; SC 10.8\ub14.1), anaesthesia duration (min) (CRI 139\ub19.,7; SC 144\ub116.2), number of ketamine rescue needed (CRI 1\ub11.15; SC 0.5\ub11.13), recovery score (CRI 1.8\ub11,2; SC 1.5\ub10,5). Also time until extubation (min) (CRI 11.5\ub15.0; SC 9.7\ub12.6), time to attain sternal (min) (CRI 41.5\ub112.2; SC 49.7\ub16.0) and standing position (min) (CRI 50.7\ub114.6; SC 57.2\ub16.,0) were not statistically different. There was statistical significance in urine production (L) (CRI 8.0\ub13.5; SC 11.1\ub14.4) and total dobutamine mcg/kg/min (CRI 0.89\ub10.35; SC 0.56\ub10.18). Subcutaneous administration of dexmedetomidine has product similar clinical effects to those achieved with CRI. It has permitted a significative reduction in dobutamine administration and a more stable depth of anaesthesia confirmed by the lower number of rescue ketamine boluses required even if not statistically different. Further studies are required to evaluate different dosages both in CRI and subcutaneous administration

Peribulbar block in equine isolated heads : development of a single needle technique and tomographic evaluation

Peribulbar block (PPB) has been used in humans as a safer alternative to retrobulbar block (RBB). PBB, depends on the diffusion of anaesthetic solution into the muscle across the connective tissue and it is performed introducing the needle within the extraconal space. The advantages are fewer complications and palpebral akinesia. In Veterinary Medicine few studies describe this technique in dogs and cats (Shilo- Benjamini et al., 2013). The aim of the study is to determinate, in equine specimens, feasibility of inferior PBB with single needle injection, by using contrast medium (CM), and to evaluate thought Computed Tomography (CT) the distribution of the injected volume and regional anaesthesia likelihood. PBB was performed in 10 orbits. The mixture injected consisted of 20 ml of physiological solution and iodinated CM at 25%. Each periorbital area underwent three CT scans. A basal acquisition to assess the needle position before the injection, a second and third scan were performed immediately after injection, and after application of pressure on the periorbital surface area to promote CM diffusion. The injectate distribution at the base and within the extraocular muscle cone (EOMC) and around the optic nerve was evaluated and scored based on Shilo-Benjamini\u2019s work of 2017. The mean minimum distance between the tip of the needle and the optic was 2,23 mm \ub10,2. The mean volume distribution before pressure application was 23.56 cm3 \ub1 2.58 and after pressure application was 27.56 cm3 \ub1 4.8. The CM median distribution around the optic nerve at the base of the EOMC was of 117\ub0 prior pressure and 189\ub0 after pressure. The CM distribution within the EOMC was present in 1 orbit prior pressure and in 3 orbits after pressure. The CM distribution at the base of EOMC was considered unlikely to provide regional anaesthesia in 2 orbits, possible in 3 orbits and likely in 5. In the present study, intraconal distribution was not consistent. For this reason, the likelihood of achieving regional anaesthesia was evaluated at the EOMC base where through the optic foramen the oculomotor, trochlear nerve, ophthalmic branch of the trigeminal nerve, and the abducens travel to reach the orbit together with the optic nerve. Whereas the maxillary branch of the trigeminal nerve passes through the foramen rotundum (Carastro 2004). Therefore, despite the lack of intraconal distribution if the EOMC base had good distribution then it was considered likely to provide regional anaesthesia. This approach needs to be evaluated in clinical trials to assess its feasibility and effectiveness in locoregional anaesthesia; moreover, further investigations on equine PBB are mandatory with higher volumes of injectate and different approaches

Multi-band optical micro-variability observations of BL Lacertae

We have observed BL Lacertae in the B, R and I bands for 2 nights in July, 1999, and 3 nights in July, 2001. The observations resulted in almost evenly sampled light curves, with an average sampling interval of ~5 min. The source is significantly variable in all bands. On average, the variability amplitude increases from ~5% in the I band, to ~5.5% in the R and ~6.5% in the B band light curves. The rising and decaying time scales are comparable within each band, but they increase from the B, to R and I band light curves. The optical power spectrum shows a red noise component with a slope of ~ -2. Cross-correlation analysis shows that in most cases the delay between the variations in the B and I band light curves is less than ~ 0.4 hrs. The cross-correlation functions are asymmetric, implying complex delays of the I band variations with respect to the B band variations. Furthermore, in one case we find that the I band variations are significantly delayed (by ~0.2 hrs) with respect to the B band variations. We also detect significant spectral variations: the spectrum becomes steeper as the flux increases, and the flattest spectral index corresponds to the maximum B band flux. Our results imply that the fast, intra-night variations of the source correspond to perturbations of different regions in the jet which cause localized injections of relativistic particles on time scales much sorter that the average sampling interval of the light curves. The variations are controlled by the cooling and light crossing time scales, which are probably comparable.Comment: Accepted for publication in A&

Injuries at the articular surface of the proximal phalanx and third metacarpal/metatarsal bone in horses, detected with low-field magnetic resonance imaging: 13 case (2010-2017)

Introduction Injuries to the fetlock region are common in horses used for athletic purposes and Magnetic Resonance Imaging (MRI) is diffusely used to diagnose bone injuries (1-3). Despite the classification used in human medicine (4), in the equine practice the terms \u201cshort incomplete fracture\u201d, \u201cstress fractures\u201d, \u201cfissure, transchondral fracture\u201d and \u201costeochondral fracture\u201d are often used interchangeably. The purpose of the study was to report the case details, diagnostic imaging findings and outcomes in sport horses with a diagnosis of traumatic injuries at the articular surfaces of metacarpophalangeal and metatarsophalangeal joint (MCPJ/MTPJ) and verify if it is possibile to differentiate between subchondral, chondral and osteochondral fracture using a low-field MRI under general anesthesia. Material and methods Magnetic Resonance examination of horses referred for lameness localised to the fetlock region over a 7-year period were reviewed. Horses were selected for inclusion in the study that had MRI findings suggestive of primary bone lesion involving the articular surface of third metacarpal/metatarsal bone (MCIII/MTIII) or proximal phalanx (P1). Signalment, detailed clinical history, athletic use, MRI findings and follow-up informations were recorded. On the basis of MRI patterns, injuries at the articular surface were classified as osteochondral fractures (OF), chondral fractures (CF), or subchondral fractures (SF) (4). Lesions were identified as an OF when defect of cartilaginous lining and/or signal change of the cartilage layer was observed in association with subchondral bone marrow lesion and arcuate or linear irregular signal change in the subchondral bone. In the SF there was no involvement of the cartilaginous lining, while in the CF there is a displaced fragment and no alteration of the subchondral black line. Results Thirteen horses have been included in the study; five horses were used for show jumping, four for flat race, two for monta vaquera and two for eventing and dressage, respectively. The median age was 8.5 years of age, with a range between 2 and 16 yo. All horses had unilateral lameness, seven horses with acute onset, while six had a chronic lameness (>12 weeks). The degree of lameness varied from grades 2/5 to 4/5. In four horses lameness was localised to the hindlimb. In four horses a subtle, radiolucent, ill-defined line was observed in the radiographic views, suggestive of short incomplete fracture. Six horses had MRI findings suggestive of OF (impacted type) involving the sagittal groove of P1 in three cases, the medial aspect of P1 in one horse and the medial condyle of MCIII/MTIII in two horses. Seven horses had SF at the medial condyle of MCIII/MTIII in three cases, at the lateral condyle of MCIII/MTIII in two cases and involving the sagittal goove of the proximal phalanx in the last two cases. No MRI findings suggestive of CF were observed in the present study. In six horses no other abnormalities were detected while in seven cases additional alterations were observed, including mild desmopathy of MCPJ/MTPJ collateral ligaments, desmopathy of the suspensory ligament branches, oblique sesamoidean ligament alteration or adhesions between deep digital flexor tendon and distal sesamoidean impar ligament. All horses were treated with a period of rest; four horses received a therapy with biphosphonates and one horse was treated with intra-articular jaluronic acid. Median time of the final follow up was 32 weeks (range: 12 to 40 weeks). Of the 13 horses included in the study, nine (69%) were sound and returned to thier previous athletic use. Three horses were still lame due to MCPJ/MTPJ pain while another one was lame due to pain localised to the suspensory ligament origin. Conclusion In equine practice, the terms osteochondral fractures, tranchondral fractures, short fracture and incomplete fracture were used interchangeably. Differentiating between osteochondral and subchondral fractures is mandatory for an accurate prognosis (4). Even if low-field MRI has a low sensitivity in detecting articular surface damage (3,5), in the present study was possible to discriminate between OF and SF in all cases. Fat-suppressed images had the capability to enhance occult bone lesions like bone marrow traumatic damage. Fat-suppressed and T1-Weighted sequences allowed to detect defect in the overlying articular surface. Despite the results reported by Gold et al. (2017) in the present study 70% of cases returned to previous athletic levels (1). Considering that all horses with a diagnosis of subchondral fracture were sound at the time of re-check while horses still lame had osteochondral fracture, we can speculate that subchondral fracture has a better prognosis. In our study all horses underwent a period of rest and none received a surgical management. Differentiating between SF and OF could help the surgeon in the treatment choice, conservative in case of subchondral injuries and surgical when cartilage involvement was detected (6,8). In the report of Smith at all. (2017), of 12 cases with a diagnosis of short incomplete fracture or osteochondral fracture, 11 returned to race after surgical repair. Even if radiographic examination can, in some cases, identify short incomplete fractures, magnetic resonance examination allows to evaluate the presence of cartilage involvement, bone marrow lesions and simultaneous soft tissue abnormalities (6). The early diagnosis of these lesions is mandatory to prevent repetiteve loading on damaged bone and possible extension to the cortex (7) that can led to catastrophic injuries In conclusion, MRI has to be considered the best imaging technique in the evaluation of an incomplete fractures, in order to differentiate between osteochondral and subchondral fractures for the elective treatment of a specific pathological entity

Injuries at the articular surface of bone in horses detected with low-field magnetic resonance imaging: 13 cases (2010-2017)

Aim of the study The purpose of the study was to report the case details, diagnostic imaging findings and outcomes in sport horses with a diagnosis of traumatic injuries (osteochondral, chondral and subchondral fractures) at the articular surfaces of metacarpophalangeal and metatarsophalangeal joint (MCPJ/MTPJ). Material and methods Magnetic Resonance (MRI) examination of horses referred for lameness localised to the fetlock region over a 7-year period were reviewed. Horses were selected for inclusion in the study that had MRI findings suggestive of primary bone lesion involving the articular surface of third metacarpal/metatarsal bone (MCIII/MTIII) or proximal phalanx (P1). Signalment, detailed clinical history, athletic use, MRI findings and follow-up informations were recorded. On the basis of MRI patterns, injuries at the articular surface were classified as osteochondral fractures (OF), chondral fractures (CF), or subchondral fractures (SF) (1). Lesions were identified as an OF when defect of cartilaginous lining and/or signal change of the cartilage layer was observed, in association with subchondral bone marrow lesion and arcuate or linear irregular signal change in the subchondral bone. In the SF there was no involvement of the cartilaginous lining, while in the CF there is a displaced fragment and no alteration of the subchondral black line. Results Thirteen horses have been included in the study; five horses were used for show jumping, four for flat race, two for monta vaquera and two for eventing and dressage, respectively. All horses had unilateral lameness, 12 horses with acute onset, while six had a chronic lameness (>12 weeks). The degree of lameness varied from grades 2/5 to 4/5. In four horses lameness was localised to the hindlimb. In four horses radiographic findings suggestive of short incomplete fractures were observed. Six horses had MRI findings suggestive of OF (impacted type) involving the sagittal groove of P1 in three cases, the medial aspect of P1 in one horse and the medial condyle of MCIII/MTIII in 2 horses. Seven horses had SF at the medial condyle of MCIII/MTIII in 3 cases, at the lateral condyle of MCIII/MTIII in 2 cases and involving the sagittal goove of the proximal phalanx in the last two cases. In six horses no other abnormalities were detected while in seven cases additional alterations were observed, including mild desmopathy of MCPJ/MTPJ collateral ligaments, desmopathy of the suspensory ligament branches, oblique sesamoidean ligament alteration or adhesions between deep digital flexor tendon and distal sesamoidean impar ligament. All horses were treated with a period of rest; four horses received a therapy with biphosphonates and one horse was treated with intra-articular jaluronic acid. Median time of the final follow up was 32 weeks (range: 12 to 40 weeks). Of the 13 horses included in the study, nine (69%) were sound and returned to thier previous athletic use. Three horses were still lame due to MCPJ/MTPJ pain while another one was lame due to pain localised to the suspensory ligament origin. Conclusion In equine practice, the terms osteochondral fractures, tranchondral fractures, short fracture and incomplete fracture were used interchangeably. Differentiating between osteochondral and subchondral fractures is mandatory for an accurate prognosis (1). Even if low-field MRI has a low sensitivity in detecting articular surface damage (2, 3), in the present study was possible to discriminate between OF and SF in all cases. Despite the results reported by Gold et al. (2017) in the present study 70% of cases returned to previous athletic levels (4). All horses with a diagnosis of SF were sound at the time of re-check while horses still lame had OF. In our study all horses underwent a period of rest and none received a surgical management. Differentiating between SF and OF could help the surgeon in the treatment choice, conservative in case of subchondral injuries and surgical when cartilage involvement was detected (5). Even if radiographic examination can identify short incomplete fractures, magnetic resonance examination allows to evaluate the presence of cartilage involvement, bone marrow lesions and soft tissue abnormalities (5). In conclusion, MRI has to be considered the best imaging technique in the evaluation of an incomplete fractures, in order to differentiate between OF and SF and opt for the elective treatment of a specific pathological entity

Injuries at the articular surface of the proximal phalanx and third metacarpal/metatarsal bone in horses, detected with low-field magnetic resonance imaging: 13 case (2010-2017)

Introduction Injuries to the fetlock region are common in horses used for athletic purposes and Magnetic Resonance Imaging (MRI) is diffusely used to diagnose bone injuries (1-3). Despite the classification used in human medicine (4), in the equine practice the terms \u201cshort incomplete fracture\u201d, \u201cstress fractures\u201d, \u201cfissure, transchondral fracture\u201d and \u201costeochondral fracture\u201d are often used interchangeably. The purpose of the study was to report the case details, diagnostic imaging findings and outcomes in sport horses with a diagnosis of traumatic injuries at the articular surfaces of metacarpophalangeal and metatarsophalangeal joint (MCPJ/MTPJ) and verify if it is possibile to differentiate between subchondral, chondral and osteochondral fracture using a low-field MRI under general anesthesia. Material and methods Magnetic Resonance examination of horses referred for lameness localised to the fetlock region over a 7-year period were reviewed. Horses were selected for inclusion in the study that had MRI findings suggestive of primary bone lesion involving the articular surface of third metacarpal/metatarsal bone (MCIII/MTIII) or proximal phalanx (P1). Signalment, detailed clinical history, athletic use, MRI findings and follow-up informations were recorded. On the basis of MRI patterns, injuries at the articular surface were classified as osteochondral fractures (OF), chondral fractures (CF), or subchondral fractures (SF) (4). Lesions were identified as an OF when defect of cartilaginous lining and/or signal change of the cartilage layer was observed in association with subchondral bone marrow lesion and arcuate or linear irregular signal change in the subchondral bone. In the SF there was no involvement of the cartilaginous lining, while in the CF there is a displaced fragment and no alteration of the subchondral black line. Results Thirteen horses have been included in the study; five horses were used for show jumping, four for flat race, two for monta vaquera and two for eventing and dressage, respectively. The median age was 8.5 years of age, with a range between 2 and 16 yo. All horses had unilateral lameness, seven horses with acute onset, while six had a chronic lameness (>12 weeks). The degree of lameness varied from grades 2/5 to 4/5. In four horses lameness was localised to the hindlimb. In four horses a subtle, radiolucent, ill-defined line was observed in the radiographic views, suggestive of short incomplete fracture. Six horses had MRI findings suggestive of OF (impacted type) involving the sagittal groove of P1 in three cases, the medial aspect of P1 in one horse and the medial condyle of MCIII/MTIII in two horses. Seven horses had SF at the medial condyle of MCIII/MTIII in three cases, at the lateral condyle of MCIII/MTIII in two cases and involving the sagittal goove of the proximal phalanx in the last two cases. No MRI findings suggestive of CF were observed in the present study. In six horses no other abnormalities were detected while in seven cases additional alterations were observed, including mild desmopathy of MCPJ/MTPJ collateral ligaments, desmopathy of the suspensory ligament branches, oblique sesamoidean ligament alteration or adhesions between deep digital flexor tendon and distal sesamoidean impar ligament. All horses were treated with a period of rest; four horses received a therapy with biphosphonates and one horse was treated with intra-articular jaluronic acid. Median time of the final follow up was 32 weeks (range: 12 to 40 weeks). Of the 13 horses included in the study, nine (69%) were sound and returned to thier previous athletic use. Three horses were still lame due to MCPJ/MTPJ pain while another one was lame due to pain localised to the suspensory ligament origin. Conclusion In equine practice, the terms osteochondral fractures, tranchondral fractures, short fracture and incomplete fracture were used interchangeably. Differentiating between osteochondral and subchondral fractures is mandatory for an accurate prognosis (4). Even if low-field MRI has a low sensitivity in detecting articular surface damage (3,5), in the present study was possible to discriminate between OF and SF in all cases. Fat-suppressed images had the capability to enhance occult bone lesions like bone marrow traumatic damage. Fat-suppressed and T1-Weighted sequences allowed to detect defect in the overlying articular surface. Despite the results reported by Gold et al. (2017) in the present study 70% of cases returned to previous athletic levels (1). Considering that all horses with a diagnosis of subchondral fracture were sound at the time of re-check while horses still lame had osteochondral fracture, we can speculate that subchondral fracture has a better prognosis. In our study all horses underwent a period of rest and none received a surgical management. Differentiating between SF and OF could help the surgeon in the treatment choice, conservative in case of subchondral injuries and surgical when cartilage involvement was detected (6,8). In the report of Smith at all. (2017), of 12 cases with a diagnosis of short incomplete fracture or osteochondral fracture, 11 returned to race after surgical repair. Even if radiographic examination can, in some cases, identify short incomplete fractures, magnetic resonance examination allows to evaluate the presence of cartilage involvement, bone marrow lesions and simultaneous soft tissue abnormalities (6). The early diagnosis of these lesions is mandatory to prevent repetiteve loading on damaged bone and possible extension to the cortex (7) that can led to catastrophic injuries In conclusion, MRI has to be considered the best imaging technique in the evaluation of an incomplete fractures, in order to differentiate between osteochondral and subchondral fractures for the elective treatment of a specific pathological entity

The use of computed tomography in the diagnosis of traumatic acetabular fractures in a colt

Pelvic fractures are uncommon in horses even if a predisposition in female horses less than 2 years old is reported in literature. Fractures involving the acetabulum are related to a trauma, often a fall. A definitive diagnosis can be reached by standing radiography, ultrasonography, computed tomography (CT), scintig- raphy and diagnostic arthroscopy. This case report describes the radiographic and CT findings in a colt with an acetabular fracture. A five month old Barockpinto colt was referred for an acute severe lameness of the left hindlimb of 3 weeks of duration. The colt was treated by the referring veterinary surgeon with phenylbutazone and box rest for one week with a mild improvement of the lameness. At presentation , the colt showed good body condition and clinical parameters were in normal range. A moderate swelling on the left coxofemoral region was noted. The colt was lame at walk and the abduction of the limb induced a moderate pain. The colt was sedated with alpha2-agonist and latero-lateral and ventro-dorsal radiographic obique views of the hip were taken with the horse in standing position The colt underwent CT of the pelvis in dorsal recumbency, under general anesthesia. Radiographic examination revealed a left coxo-femoral dias- tasis, irregular margins of the acetabulum associated with radiolucent areas and subchondral sclerosis of the fovea capitis. Computed tomography findings consisted in multiple fractures involving the dorsal acetabular margin in association with dorso-cranio-lateral dislocation of the femoral head. In proximity of the caudo- ventral aspect of the acetabular fossa were present several small mineralized fragments. Moderate sclerosis was seen in the fovea capitis and a mild osteopenia of the left femoral head. Despite the radiographic views allowed to recognize the presence of a femoral head luxation and irregularities of the acetabular margings, only CT images revealed the presence of multiple fractures along the acetabular rim improving the prognos- tic value for the patient. Compared with radiography in dorsal recumbency with the limbs in a frog-legged posture, extended positioning of hindlimbs used fot the CT acquisition, induced less stress on the fracture3 In conclusion, on the basis of our experinece and in accordance with other studies, CT examination provides more valuable information than radiographs in the diagnosis of the coxo-femoral joint disease