Urine congophilia associated with preeclampsia does not persist 6-months postpartum.

INTRODUCTION: Preeclampsia is a common hypertensive disorder of pregnancy. Several studies have demonstrated that protein aggregates, detected through urine congophilia, is associated with preeclampsia; however, it has yet to be investigated whether urine congophilia remains postpartum in these women. In this study, we aimed to augment prior studies and determine whether urine congophilia is present postpartum. METHODS: Women were recruited from Lyell McEwin Hospital, South Australia. Urine samples were collected during pregnancy and 6-months postpartum from women with non-preeclampsia pregnancies (n = 48) and women with pregnancies complicated by preeclampsia (n = 42). A Congo Red Dot blot test, total protein and creatinine levels from urine, as well as serum Soluble fms-like tyrosine kinase 1 to placental growth factor ratio (sFlt-1:PlGF), were assessed and correlated. RESULTS: Preeclamptic women exhibited increased urine congophilia (P < 0.01), sFlt-1:PlGF ratio (P < 0.0001) and total protein (P < 0.01) during pregnancy; with a positive correlation between urine congophilia and total protein across the entire cohort (P < 0.0001). Although urine congophilia was no longer detected 6-months postpartum in preeclamptic women, total protein remained elevated (P < 0.05). sFlt-1:PlGF ratio during pregnancy was positively correlated with congophilia across the cohort (P = 0.0007). Serum creatinine was also higher in preeclamptic women during pregnancy (P < 0.001). DISCUSSION: These results support that urine congophilia is significantly elevated in pregnancies complicated with preeclampsia and show that it does not continue postpartum, although larger cohort studies are needed to determine its feasibility as a diagnostic marker.

Radiographic and arthroscopic features of third carpal bone slab fractures and their impact on racing performance following arthroscopic repair in a population of racing Thoroughbreds in the UK.

BACKGROUND: Slab fractures of the third carpal bone (C3) are a common injury of Thoroughbred racehorses. Results of arthroscopically guided repair have not been reported since the initial description of the technique in 1986. Additionally, fracture details and racing outcomes in a population of Thoroughbreds racing under UK jurisdiction have not previously been described. OBJECTIVES: To report the frequency distribution of C3 slab fractures and to determine the impact on racing performance following arthroscopically guided repair in a population of Thoroughbred racehorses. STUDY DESIGN: Retrospective case series. METHODS: Case records of Thoroughbred racehorses undergoing arthroscopically guided repair of C3 slab fractures at Newmarket Equine Hospital between 2006 and 2015 were retrieved. Radiographs and arthroscopic studies were reviewed. The effect of demography and fracture morphology on racing outcome was evaluated. RESULTS: C3 slab fractures occurred most commonly through the radial facet in a frontal plane (45/71 63.4%). Comminution was identified during arthroscopy in 42/71 (59.2%) fractures and occurred most frequently at the palmar margin of the fracture. Forty-one out of 65 horses (63.1%) raced at least once post-operatively. Females were less likely to return to racing compared to males (P<0.001). Horses that had raced before injury were more likely (OR 4.4, 95% CI 1.4-13.5, P = 0.01) to race after injury compared to horses that were unraced at the time of injury. After injury horses had a small but significant reduction in racing performance. MAIN LIMITATIONS: The series is a preselected population of Thoroughbred racehorses which referring veterinary surgeons considered potential candidates for surgical repair. CONCLUSION: Fracture configurations can be identified radiographically but is not a reliable predictor of comminution or other intra-articular lesions. Arthroscopy not only directs repair but also identifies and facilitates management of concurrent lesions. The results reported should assist in formulating appropriate prognoses for Thoroughbred horses racing in the UK.

Surgical management of marginal tears/avulsions of the suspensory ligament branches in 29 Thoroughbred racehorses.

BACKGROUND: Suspensory ligament branch injuries are common in horses. Most of these injuries are grouped together and considered as a single pathologic entity. OBJECTIVES: To report a specific injury of the abaxial margin of the suspensory ligament branches and to report its surgical management and outcome. STUDY DESIGN: Retrospective case series. METHODS: All horses with suspensory ligament branch injuries over a 9-year period (2007-2015) were identified. Horses with injuries which, on ultrasonographic examination, appeared to have defects in the abaxial margin of the suspensory ligament branch, that were subsequently confirmed during surgery were selected. RESULTS: Twenty-nine cases fulfilled the inclusion criteria with a specific lesion location on the abaxial margin of the suspensory ligament branch. Nineteen horses raced successfully after surgery, nine returned to training but failed to race and one was lost to follow-up. MAIN LIMITATIONS: The absence of a comparable population of non-surgically managed horses in this study means that the contribution of removing torn tissue cannot confidently be assessed. CONCLUSIONS: The location and morphology of injuries described in this study is consistent, which suggests aetiopathogenic commonality. This case series suggests this type of injury has an identity of its own, differs from other types of suspensory ligament branch injuries and represents a previously undescribed subgroup.

A review of international clinical practice guidelines for the use of oxygen in the delivery room resuscitation of preterm infants.

AIM: To collate and assess international clinical practice guidelines (CPG) to determine current recommendations guiding oxygen management for respiratory stabilisation of preterm infants at delivery. METHODS: A search of public databases using the terms 'clinical practice guidelines', 'preterm', 'oxygen' and 'resuscitation' was made and complemented by direct query to consensus groups, resuscitation expert committees and clinicians. Data were extracted to include the three criteria for assessment: country of origin, gestation and initial FiO2 and target SpO2 for the first 10 minutes of life. RESULTS: A total of 45 CPGs were identified: 36 provided gestation specific recommendations (<28 to <37 weeks) while eight distinguished only between 'preterm' and 'term'. The most frequently recommended initial FiO2 were between 0.21 and 0.3 (n = 17). Most countries suggested altering FiO2 to meet SpO2 targets recommended by expert committees, However, specific five-minute SpO2 targets differed by up to 20% (70-90%) between guidelines. Five countries did not specify SpO2 targets. CONCLUSION: CPG recommendations for delivery room oxygen management of preterm infants vary greatly, particularly in regard to gestational ages, initial FiO2 and SpO2 targets and most acknowledge the lack of evidence behind these recommendations. Sufficiently large and well-designed randomised studies are needed to inform on this important practice.

Frequency distribution of osteochondral fragmentation of the dorsoproximal articular surface of the proximal phalanx in racing Thoroughbreds in the UK.

BACKGROUND: Osteochondral fragmentation of the dorsoproximal margin of the proximal phalanx is commonly recognised in racing Thoroughbreds. Frequency distribution has been documented in racing Thoroughbreds and Quarter Horses in the USA and in European Warmbloods but no data have been published from the UK. Concurrent intra-articular soft tissue lesions and radiographic accuracy of fragment distribution in racing Thoroughbreds have not previously been reported. OBJECTIVES: To document frequency distribution of dorsoproximal fragmentation of the proximal phalanx in a UK population of racing Thoroughbreds and to compare this with published data. To document concurrent intra-articular lesions identified arthroscopically and radiographic accuracy of fragment distribution. STUDY DESIGN: A retrospective single centre-based, observational study. METHODS: Surgical reports and radiographs of all racing Thoroughbreds that underwent arthroscopic surgery for removal of fragmentation from the dorsoproximal margin of the proximal phalanx at Newmarket Equine Hospital between 2011 and 2015 were reviewed. RESULTS: Two hundred and forty-two (85.8%) horses were in or being prepared for flat racing. Osteochondral fragmentation of the dorsoproximal aspect of the proximal phalanx was present in 428 fetlock joints of 282 horses, consisting of 194 (45.3%) left and 188 (43.9%) right metacarpophalangeal joints, and 20 (4.7%) left and 26 (6.1%) right metatarsophalangeal joints. Fragmentation was located dorsomedially in 316 (73.8%), dorsolaterally in 32 (7.5%) and biaxially in 80 (18.7%) joints. Concurrent soft tissue lesions were identified in 168 (39.3%) joints. Radiographic evidence of fragmentation was visible in 320 joints (74.8%). MAIN LIMITATIONS: Limited numbers preclude conclusions with respect to yearlings and horses in jump race training. CONCLUSION: Dorsoproximal fragmentation of the proximal phalanx occurred most frequently medially and in the forelimbs. Sidedness was not demonstrated. Although similar to previously reported data, variance in limb distribution is evident. Further research is required to determine whether concurrent intra-articular soft tissue lesions are aetiopathogenic or an additional result of the pathological changes leading to fragmentation. Fragmentation site was not always accurately identified radiographically. The Summary is available in Spanish - see Supporting information.

Short frontal plane fractures involving the dorsoproximal articular surface of the proximal phalanx: Description of the injury and a technique for repair.

BACKGROUND: Chip fractures of the dorsoproximal articular margin of the proximal phalanx are common injuries in racehorses. Large fractures can extend distal to the joint capsule insertion and have been described as dorsal frontal fractures. OBJECTIVES: To report the location and morphology of short frontal plane fractures involving the dorsoproximal articular surface of the proximal phalanx and describe a technique for repair under arthroscopic and radiographic guidance. STUDY DESIGN: Single centre retrospective case study. METHODS: Case records of horses with frontal plane fractures restricted to the dorsoproximal epiphysis and metaphysis of the proximal phalanx referred to Newmarket Equine Hospital were retrieved, images reviewed and lesion morphology described. A technique for repair and the results obtained are reported. RESULTS: A total of 22 fractures in 21 horses commencing at the proximal articular surface exited the dorsal cortex of the proximal phalanx distal to the metacarpophalangeal/metatarsophalangeal joint capsule in 17 hind- and five forelimbs. All were in Thoroughbred racehorses. In 16 cases these were acute racing or training injuries; 20 fractures were medial, one lateral and one was midline. All were repaired with a single lag screw using arthroscopic and radiographically determined landmarks. A total of 16 horses raced after surgery with performance data similar to their preinjury levels. MAIN LIMITATIONS: The study demonstrates substantial morphological similarities between individual lesions supporting a common pathophysiology, but does not identify precise causation. There are no cases managed differently that might permit assessment of the comparative efficacy of the treatment described. CONCLUSIONS: Short frontal plane fractures involving the dorsoproximal margin of the proximal phalanx that exit the bone distal to the metacarpophalangeal/metatarsophalangeal joint capsule have substantial morphological similarities, are amenable to minimally invasive repair and carry a good prognosis for return to training and racing.

Parasagittal fractures of the proximal phalanx in Thoroughbred racehorses in the UK: Outcome of repaired fractures in 113 cases (2007-2011).

BACKGROUND: Thirty years have elapsed since the last published review of outcome following fracture of the proximal phalanx in Thoroughbred racehorses in the UK and contemporary results are needed to be able to advise of expected outcome. OBJECTIVES: Collect and analyse outcome data following repair of fractures of the proximal phalanx in Thoroughbred racehorses in the UK. STUDY DESIGN: Retrospective case series. METHODS: Case records of all Thoroughbred racehorses admitted to Newmarket Equine Hospital for evaluation of a parasagittal fracture of the proximal phalanx during a 5 years period were reviewed. Follow-up data regarding racing careers was collected for horses that underwent repair. Following exclusion of outliers, cases with incomplete data sets and comminuted fractures, mixed effect logistic regression was used to identify variables affecting returning to racing and odds ratios and confidence intervals calculated. RESULTS: Of 113 repaired cases, fracture configurations included short incomplete parasagittal (n = 12), long incomplete parasagittal (n = 86), complete parasagittal (n = 12) and comminuted (n = 3). A total of 54 (48%) cases raced after surgery. Horses that fractured at 2 years of age had increased odds of racing following surgery than those older than 2 years of age (OR 1.34; 95% CI 1.13-1.59, P = 0.002). Horses sustaining short incomplete parasagittal fractures had increased odds of racing following surgery compared with those with complete parasagittal fractures (OR 2.62; 95% CI 1.36-5.07, P = 0.006). No horses with comminuted fractures returned to racing. MAIN LIMITATIONS: Data are relevant only to Thoroughbred racehorses in the UK. CONCLUSIONS: Approximately half of the cases in this series raced following surgical repair. More 2-year-old horses raced following surgery, but this likely reflects horses, specifically older horses, passing out of training from unrelated factors. Fracture configuration affects odds of racing, which is relevant to owners when deciding on treatment.

Development of Real-Time RT-PCR Assays for Detection and Typing of Epizootic Haemorrhagic Disease Virus.

Epizootic haemorrhagic disease virus (EHDV) is an emerging arboviral pathogen of wild and domestic ruminants worldwide. It is closely related to bluetongue virus (BTV) and is transmitted by adult females of competent Culicoides vector species. The EHDV genome consists of ten linear double-stranded (ds)RNA segments, encoding five non-structural and seven structural proteins. Genome-segment reassortment contributes to a high level of genetic variation in individual virus strains, particularly in the areas where multiple and distinct virus lineages co-circulate. In spite of the relatively close relationship between BTV and EHDV herd-immunity to BTV does not appear to protect against the introduction and infection of animals by EHDV. Although EHDV can cause up to 80% morbidity in affected animals, vaccination with the homologous EHDV serotype is protective. Outer-capsid protein VP2, encoded by Seg-2, is the most variable of the EHDV proteins and determines both the specificity of reactions with neutralizing antibodies and consequently the identity of the eight EHDV serotypes. In contrast, VP6 (the viral helicase), encoded by Seg-9, is highly conserved, representing a virus species/serogroup-specific antigen. We report the development and evaluation of quantitative (q)RT-PCR assays targeting EHDV Seg-9 that can detect all EHDV strains (regardless of geographic origin/topotype/serotype), as well as type-specific assays targeting Seg-2 of the eight EHDV serotypes. The assays were evaluated using orbivirus isolates from the 'Orbivirus reference collection' (ORC) at The Pirbright Institute and were shown to be EHDV pan-reactive or type-specific. They can be used for rapid, sensitive and reliable detection and identification (typing) of EHDV RNA from infected blood, tissue samples, homogenized Culicoides, or tissue culture supernatant. None of the assays detected RNA from closely related but heterologous orbiviruses, or from uninfected host animals or cell cultures. The techniques presented could be used for both surveillance and vaccine matching (serotype identification) as part of control strategies for incursions in wild and domestic animal species.

Slab fractures of the third tarsal bone: Minimally invasive repair using a single 3.5 mm cortex screw placed in lag fashion in 17 Thoroughbred racehorses.

REASONS FOR PERFORMING THE STUDY: A technique for minimally invasive repair of slab fractures of the third tarsal bone has not previously been reported. Results of third tarsal bone slab fracture repair in Thoroughbred racehorses are lacking. OBJECTIVES: To report the outcomes of repair of uniplanar frontal slab factures of the third tarsal bone using a single 3.5 mm cortex screw in lag fashion. STUDY DESIGN: Retrospective case series. METHODS: Case records of horses that had undergone this procedure were reviewed. RESULTS: Seventeen horses underwent surgery. Eighteen percent of cases had wedge shaped third tarsal bones. A point midway between the long and lateral digital extensor tendons and centrodistal and tarsometatarsal joints created a suitable entry site for implants. The fracture location, configuration and curvature of the third tarsal bone and associated joints requires a dorsolateral proximal-plantaromedial distal trajectory for the screw, which was determined by preplaced needles. There were no complications and fractures healed in all cases at 4-6 months post surgery. Seventy-nine percent of horses returned to racing and, at the time of reporting, 3 are in post operative rehabilitation programmes. CONCLUSION: The technique reported provides a safe, appropriate and repeatable means of repairing slab fractures of the third tarsal bone. Surgical repair is a viable alternative to conservative management.

Peri-anaesthetic complications in an equine referral hospital: Risk factors for post anaesthetic colic.

REASONS FOR PERFORMING STUDY: Peri-anaesthetic complications are relatively common in equine patients and further investigations are warranted to identify manageable risk factors. OBJECTIVES: To report morbidity and mortality rates and identify associated risk factors for horses undergoing general anaesthesia, within a predominantly racing Thoroughbred (TB) population. STUDY DESIGN: Single centre retrospective observational study. METHODS: Anaesthetic and case records of all horses ≥12 months old undergoing general anaesthesia at Newmarket Equine Hospital between August 2010 and April 2012 were analysed, excluding emergency abdominal/dystocia procedures or traumatology cases with cardiovascular compromise. Mortality and morbidity rates were calculated and described. Uni- and multivariable analyses were used to investigate the relationship between the principal complication, post anaesthetic colic (PAC) and risk factors. RESULTS: A total of 1067 anaesthetic records of 1021 horses were included in the study; of these, 702 horses (65.8%) were TB, 169 (15.8%) developed a complication within 7 days of general anaesthesia and 10 (0.94%) died as a result. The most prevalent morbidity was PAC, 111 horses (10.5%) developed colic within 7 days of general anaesthesia. Thoroughbred horses (odds ratio [OR] 2.93, 95% confidence interval [CI] 1.73-4.96) and horses receiving sodium benzylpenicillin (NaBP) (OR 2.77, 95% CI 1.69-4.50) were at increased risk of PAC. CONCLUSIONS: Thoroughbred racehorses were identified as at increased risk of PAC in this study and might benefit from more critical evaluation of post anaesthetic gastrointestinal function. An alternative to the administration of NaBP for prophylactic antimicrobial therapy needs to be further investigated if its role in PAC is confirmed by other studies.

Resuscitating preterm infants with 100% oxygen is associated with higher oxidative stress than room air.

AIM: The starting fraction of inspired oxygen for preterm resuscitation is a matter of debate, and the use of room air in full-term asphyxiated infants reduces oxidative stress. This study compared oxidative stress in preterm infants randomised for resuscitation with either 100% oxygen or room air titrated to internationally recommended levels of preductal oxygen saturations. METHODS: Blood was collected at birth, two and 12 hours of age from 119 infants <32 weeks of gestation randomised to resuscitation with either 100% oxygen (n = 60) or room air (n = 59). Oxidative stress markers, including advanced oxidative protein products (AOPP) and isoprostanes (IsoP), were measured with high-performance liquid chromatography and mass spectrometry. RESULTS: Significantly higher levels of AOPP were found at 12 hours in the 100% oxygen group (p < 0.05). Increases between two- and 12-hour AOPP (p = 0.004) and IsoP (p = 0.032) concentrations were significantly higher in the 100% oxygen group. CONCLUSION: Initial resuscitation with room air versus 100% oxygen was associated with lower protein oxidation at 12 hour and a lower magnitude of increase in AOPP and IsoP levels between two and 12 hours of life. Correlations with clinical outcomes will be vital to optimise the use of oxygen in preterm resuscitation.

Morphologic and morphometric features of the calcaneal insertions of the superficial digital flexor tendon in the horse.

INTRODUCTION: Accurate description of the calcaneal insertions of the superficial digital flexor tendon (SDFT) is lacking and inconsistent. The aim of this study was to undertake morphologic and morphometic evaluations of these structures to assist in elucidating their functional and pathogenic roles in displacement of the SDFT from the calcaneal tuber. METHOD: Dissections were performed on 10 normal cadaveric hindlimbs. The anatomy was photographed to allow measurements at repeatable locations and differences in SDFT dimensions at the various locations were compared using a paired student t-test. RESULTS: This study demonstrated that the calcaneal insertions of the SDFT are independent from the overlying tarsal insertions of the biceps femoris and semitendinosus, which blend into the plantar surface of the fibrocartilaginous cap (FCC) of the SDFT before inserting dorsal to the insertion of the SDFT on the calcaneal tuber. The lateral insertion of the SDFT is larger in cross-sectional area (median: 219 mm²) at its origin from the FCC than its medial counterpart (median: 159 mm², p = 0.004) and has a more complex fibre alignment. The lateral site of attachment of the SDFT on the calcaneal tuber is dorsolateral to the insertion of the gastrocnemius tendon and is larger (median: 525 mm²) than the medial insertion (median: 428 mm², p = 0.036), which inserts distal to the insertion of the gastrocnemius tendon. CONCLUSION: The features identified in this study suggest that the calcaneal insertions of the SDFT are complex and their morphological and morphometric differences are likely to contribute to clinical lesions identified at this site.

Do maternal opioids reduce neonatal regional brain volumes? A pilot study.

OBJECTIVE: A substantial number of children exposed to gestational opioids have neurodevelopmental, behavioral and cognitive problems. Opioids are not neuroteratogens but whether they affect the developing brain in more subtle ways (for example, volume loss) is unclear. We aimed to determine the feasibility of using magnetic resonance imaging (MRI) to assess volumetric changes in healthy opioid-exposed infants. STUDY DESIGN: Observational pilot cohort study conducted in two maternity hospitals in New South Wales, Australia. Maternal history and neonatal urine and meconium screens were obtained to confirm drug exposure. Volumetric analysis of MRI scans was performed with the ITK-snap program. RESULT: Scans for 16 infants (mean (s.d.) gestational age: 40.9 (1.5) weeks, birth weight: 3022.5 (476.6) g, head circumference (HC): 33.7 (1.5 cm)) were analyzed. Six (37.5%) infants had HC <25th percentile. Fourteen mothers used methadone, four used buprenorphine and 11 used more than one opioid (including heroin, seven). All scans were structurally normal whole brain volumes (357.4 (63.8)) and basal ganglia (14.5 (3.5)) ml were significantly smaller than population means (425.4 (4.8), 17.1 (4.4) ml, respectively) but lateral ventricular volumes (3.5 (1.8) ml) were larger than population values (2.1(1.5)) ml. CONCLUSION: Our pilot study suggests that brain volumes of opioid-exposed babies may be smaller than population means and that specific regions, for example, basal ganglia, that are involved in neurotransmission, may be particularly affected. Larger studies including correlation with neurodevelopmental outcomes are warranted to substantiate this finding.

Reduced nephron endowment in the neonates of Indigenous Australian peoples.

Rates of chronic kidney disease (CKD) among Indigenous groups in Australia exceed non-Indigenous rates eight-fold. Using kidney volume as a surrogate for nephron number, we carried out a study to determine if Indigenous neonates have a smaller kidney volume (and thus a reduced nephron number) from birth compared with non-Indigenous neonates. We recruited term and preterm neonates (<32 weeks) at a tertiary care neonatal unit over a 12 months period. Preterm neonates were assessed (renal sonography and renal function measurement) at 32 weeks corrected age (CA) and again at 38 weeks CA when blood pressure was also measured. All term neonates were assessed in the first post-natal week, including renal sonography, renal function and blood pressure measurement. The primary outcome measured was total kidney volume (TKV) and estimated glomerular filtration rate (eGFR) was a secondary outcome. Data was available for 44 preterm (11 Indigenous) and 39 term (13 Indigenous) neonates. TKV of Indigenous neonates was significantly lower at 32 weeks [12.0 (2.0) v. 15.4 (5.1) ml; P=0.03] and 38 weeks CA [18.6 (4.0) v. 22.6 (5.9) ml; P=0.04] respectively. Term Indigenous neonates also had smaller kidney volumes compared with non-Indigenous neonates. Despite a smaller kidney volume (and reduced nephron number), Indigenous neonates did not have a significantly lower eGFR. Indigenous neonates achieve similar eGFRs to Non-Indigenous neonates, presumably through a higher single nephron filtration rate. This places Indigenous neonates at a greater risk of long-term kidney damage later in life.

Are there radiologically identifiable prodromal changes in Thoroughbred racehorses with parasagittal fractures of the proximal phalanx?

REASONS FOR PERFORMING STUDY: Fractures of the proximal phalanx are generally considered to result from monotonic supraphysiological loads, but radiological observations from clinical cases suggest there may be a stress-related aetiology. OBJECTIVES: To determine whether there are radiologically identifiable prodromal changes in Thoroughbred racehorses with confirmed parasagittal fractures of the proximal phalanx. STUDY DESIGN: Retrospective cross-sectional study. METHODS: Case records and radiographs of Thoroughbred racehorses with parasagittal fractures of the proximal phalanx were analysed. Thickness of the subchondral bone plate was measured in fractured and contralateral limbs, and additional radiological features consistent with prodromal fracture pathology documented. RESULTS: The subchondral bone plate was significantly thicker in affected than in contralateral limbs. Evidence of additional prodromal fracture pathology was observed in 15/110 (14%) limbs with parasagittal fractures, and in 4% of contralateral limbs. CONCLUSIONS: The results of this study are not consistent with monotonic loading as a cause of fracture in at least a proportion of cases, but suggest a stress-related aetiology. Increased thickness of the subchondral bone plate may reflect (failed) adaptive changes that precede fracture. POTENTIAL RELEVANCE: Better understanding of the aetiology of fractures of the proximal phalanx may help develop strategies to reduce the risk of fracture.

Radiographic configuration and healing of 121 fractures of the proximal phalanx in 120 Thoroughbred racehorses (2007-2011).

REASONS FOR PERFORMING STUDY: Although fractures of the proximal phalanx are one of the most common long bone fractures of Thoroughbred horses in training, limited details on variations in morphology and radiological progression have been published. OBJECTIVES: To describe in detail the configuration of parasagittal fractures of the proximal phalanx in a group of Thoroughbred racehorses, to report fracture distribution within this group of horses and to document radiological progression of fracture healing in cases treated by internal fixation. STUDY DESIGN: Restrospective case series. METHODS: Case records and radiographs of Thoroughbred racehorses with parasagittal fractures of the proximal phalanx admitted to Newmarket Equine Hospital between 2007 and 2011 were analysed. RESULTS: One hundred and twenty-one fractures were identified in 120 Thoroughbred racehorses. Fractures were frequently more complex than was appreciated immediately following injury; a feature that has not been reported previously. There was seasonality of fractures in 2- and 3-year-old horses, but not in older horses. CONCLUSIONS AND POTENTIAL RELEVANCE: Fractures of the proximal phalanx may be more complex than recognised previously, although often their complexity cannot be identified radiographically immediately following injury. The seasonality observed in 2- and 3-year-old horses is most likely to be a consequence of the timing of the turf-racing season in the UK. The Summary is available in Chinese - see Supporting information.

A new technique for subtotal (cranial wedge) ostectomy in the treatment of impinging/overriding spinous processes: description of technique and outcome of 25 cases.

REASONS FOR PERFORMING STUDY: Surgical management for overriding spinous processes of the thoracolumbar vertebrae (SPs) is often favoured when conservative therapies have failed, pathology is severe, or in competition horses constrained by drug withdrawal periods. OBJECTIVES: To evaluate whether subtotal (cranial wedge) ostectomy represents an effective treatment for overriding SPs, with short surgery time and low complication rates, maintains the contour of the spine and produces a functionally and cosmetically better outcome than previously reported surgical techniques for management of overriding/impinging SPs. STUDY DESIGN: Retrospective study. METHODS: A new technique is described and records were retrieved for 25 cases that had undergone the procedure at Newmarket Equine Hospital between 2009 and 2011. Case records were evaluated for anamnesis, clinical findings and details of surgical and post operative management. Outcome of surgery was assessed by telephone questionnaire with owners, relating to both functional and cosmetic results. RESULTS: Of cases treated using the described technique, 78.9% had resolution of clinical signs and returned to full work and a further 18.2% were improved. Outcome was unrelated to number of SPs resected or mean radiographic grade of impingement. Cosmetic outcome was described as excellent in 81.8% and good in the remainder. Surgery time ranged from 20 to 70 (median 30) min and there were no intra- or post operative complications. CONCLUSIONS: In contrast to previously described amputation techniques, subtotal (cranial wedge) ostectomy removes only impinging portions of SPs. General anaesthesia and lateral recumbency facilitate access and enable a short surgery time. The procedure maintains the contour of the back and has fewer complications, but produces functional outcomes similar to more invasive procedures.

Identification and treatment of osteochondritis dissecans of the distal sagittal ridge of the third metacarpal bone.

REASONS FOR PERFORMING STUDY: Osteochondritis dissecans (OCD) of the distal sagittal ridge of the third metacarpal bone (McIII) has not previously been described in the literature. OBJECTIVES: To describe the clinical, radiological and arthroscopic features of OCD of the distal sagittal ridge of the McIII and to report outcome in a series of cases. STUDY DESIGN: Retrospective case series. METHODS: Case records and images of horses with OCD of the distal sagittal ridge of the McIII admitted to a single referral centre between February 2006 and February 2013 were reviewed. Follow-up information was obtained by telephone questionnaire and/or racing performance. RESULTS: Osteochondritis dissecans of the distal sagittal ridge of the McIII was found in 16 lame horses; 9 unilaterally and 7 bilaterally. Lesions were consistently identified with flexed lateromedial radiographs and in 21 joints in dorsopalmar projections also. These were arthroscopically accessible from the dorsal compartment with metacarpophalangeal joints maximally flexed. This permitted fragment removal and lesion debridement. Thirteen of 14 horses with follow-up of ≥12 months post surgery performed athletically including 11 of 12 Thoroughbreds that raced. CONCLUSIONS: Unlike more proximal lesions, OCD of the distal sagittal ridge appears to affect the McIII preferentially. Lesions were identified on dorsopalmar and flexed lateromedial radiographs only and are amenable to arthroscopic surgery. Clinicians should be aware of the potential for OCD to affect the distal sagittal ridge of the McIII together with the radiographic projections needed to identify its presence. A modified arthroscopic approach to the dorsal metacarpophalangeal joint is necessary in order to access lesions.

Frontal plane fractures of the accessory carpal bone and implications for the carpal sheath of the digital flexor tendons.

REASONS FOR PERFORMING STUDY: Accurate radiological and ultrasonographic descriptions of frontal plane fractures of the accessory carpal bone (ACB) are lacking, and implications of these fractures for the carpal sheath and its contents have not previously been reported. OBJECTIVES: Aims were as follows: 1) to describe the location and radiological features of frontal plane fractures of the ACB; 2) to document communication of displaced fractures with the carpal sheath and consequent injury to the deep digital flexor tendon (DDFT); 3) to describe ultrasonographic identification of lesions; and 4) to report tenoscopic evaluation and treatment. STUDY DESIGN: Retrospective case series. METHODS: Analysis of frontal plane fractures of the ACB referred to a single hospital between 2006 and 2012, including review of radiographic, ultrasonographic and tenoscopic images. RESULTS: Nine fractures were identified, of which 8 displaced fractures all communicated with the carpal sheath. Comminuted fragments and/or protruding fracture margins lacerated the lateral margin of the enclosed DDFT. This was identifiable ultrasonographically and confirmed at tenoscopy in 7 cases. Treatment in these horses consisted of removal of torn tendon tissue together with fragmentation and protuberant fracture edges, and 7 of 7 cases returned to work. One horse with a nondisplaced fracture was managed with immobilisation; the fracture healed, and the horse returned to work. One horse with a displaced fracture was retired to stud. CONCLUSIONS: Frontal plane fractures of the ACB occur palmar to the groove in its lateral margin for the tendon of insertion of ulnaris lateralis. Comminuted fragments can displace distally within the carpal sheath to a mid-metacarpal level or abaxially to lie extrathecally, lateral to the parent bone. Displaced fractures communicate with the carpal sheath and traumatise the DDFT.