There are many reports describing fractures in the bony elements of the equine fetlock joint and a few of these discuss possible relationships of these fractures to the mechanical loading of these bones. The likelihood of fracture must be related to the size and shape of bones involved, but information concerning the normal range in size and shape of these bones in horses is lacking. This study aimed to identify morphometrical variations of these bones within different groups of horses. Right and left metacarpal, proximal phalangeal and proximal sesamoid bones were collected from 10 Thoroughbreds (TB), five Standardbreds (SB) and eight Ponies (P) euthanized for non-orthopaedic reasons. All bones were boiled, cleaned and dried. Dimensional parameters were measured using a custom-built apparatus, calliper and plastic tape. The width and depth of the medial condyles of Mc3 were greater than the lateral condyles in all groups. The length to the lateral condyle was greater than the length to the medial condyle of Mc3, and the lengths of the lateral sides of the Mc3 and P1 bones were greater than the lengths of the medial sides in both forelimbs of all groups. The lateral sesamoids were similar to, or larger than, the medial sesamoids in all dimensions. There were some morphometrical variations in the bony elements of the equine fetlock joints in all groups.
Abdulrhman Mohamed Salah Alrtib, C J Philip, Aiman Hussein Saleh Oheida, Helen M S Davies(4-2012)

Several reports have discussed possible bony morphological causes of fetlock pathology but without relating them to its morphometry. Radiographic measurement is widely used in constructing numerical databases of bone morphometry. Such measurements would not be reliable unless all factors affecting the radiographs were considered. Therefore, this study aimed to establish a specific dorsopalmar view (DP) for fetlock radiographic measurements, and then to develop reliable and repeatable fetlock parameters that represent fetlock conformation on those DP radiographs. Ten cadaveric forelimbs from ten adult horses were cut at the distal third of the radius and mounted in a normal posture for DP radiography. Specific features on fetlock bones were used as landmarks to identify the DP at zero degrees. Other bony features were selected as landmarks for developing fetlock parameters on these radiographs. Twenty-seven parameters were designed in the form of angles (12) and ratios (15). The repeatability and consistency of each parameter was tested. A specific fetlock DP view was determined at zero degrees based on certain landmarks. All angular and ratio parameters showed high reliability and consistency in their measurements. The established parameters provide an opportunity to test the relationship between fetlock morphometrics and performance, or the likelihood of certain pathologies.
Abdulrhman Mohamed Salah Alrtib, Aiman Hussein Saleh Oheida, Mohamed Hamrouni S. Abushhiwa, Helen M S Davies(3-2019)

Carpal conformation is thought to contribute to the frequency of carpal pathology so non-invasive measurement of carpal morphometry would be useful to identify joints at risk. However, there are scant radiographic morphometrical details for the carpals of Thoroughbred (TB) and Standardbred (SB) racehorses even though these breeds differ in the incidence of carpal damage. This study aimed to identify morphometrical similarities and differences in carpal conformation in TB and SB. Thirty carpal dorsopalmar radiographs (DP) were collected from 15 TB and 15 SB. All DP radiographs were at zero degrees or within the acceptable range of rotation. Twelve carpal radiographic parameters were selected and measured on each radiograph. Statistical analysis found significant differences in four carpal parameters. These parameters revealed that the middle carpal joint in SB was significantly more angled distomedially whereas the radial distal metaphysis showed a greater distolateral inclination in TB. The radiocarpal and the carpometacarpal articulations exhibited common features in the two groups of horses. These carpal traits in TB and SB highlight their potential association with loading distribution and pathology. Measuring carpi from untrained and injured horses is necessary to establish breed specific features for the ideal carpal conformation in each of these breeds.
Aiman Hussein Saleh Oheida, Abdulrhman Mohamed Salah Alrtib, Aiman Abdulghader Salim Shalgum, Mansur Ennuri Moftah Shmela, Mohamed A Marzok, Helen M S Davies(4-2019)

The forelimb fetlock joint and its bony components are a common site of injury in racing horses. We hypothesized that the variations in relative density of these bones might correspond to their mechanical properties. This study aimed first to identify the relative density of third metacarpal bone (Mc3), proximal phalanx (P1) and proximal sesamoid bones (PSBs) of Thoroughbred race horses. Second, to determine whether there was any difference and/or similarity in the relative density between and within the bones. Bones from right and left forelimbs of 10 horses were collected and prepared by boiling and drying. Dry weight and volume for each bone were measured and the relative density was then calculated. Relative density of Mc3 was substantially greater than the other two bones with a mean of 1.7 ± 0.06. Relative density of P1 and PSBs showed a high similarity especially between P1 and the medial PSBs. Neither the comparisons between right and left sides nor between lateral and medial PSBs showed any significant differences. P1 had the most consistent relative density within right and left sides. Larger relative density in Mc3 and the similarity between P1 and PSBs presume a more important role of the bone mass on their properties than the volume.
Abdulrhman Mohamed Salah Alrtib, Aiman Hussein Saleh Oheida, Ali Omar Alarif Boker, Aiman Abdulghader Salim Shalgum, Helen M S Davies(12-2018)

Relationships between carpal morphology and carpal pathology might assist in identifying horses at risk of carpal pathology. This study was aimed to investigate the hypothesis that carpal morphology is related to the incidence of carpal pathology in racing Thoroughbreds. Ten carpal parameters were used to measure carpal morphology on dorsopalmar (DP) carpal radiographs. Radiographs were collected from 19 experienced Thoroughbred race horses with no evidence of carpal damage(normal)and 72 horses with carpal damage (clinical). All radiographs were at a defined position called zero degrees (ZDP) or within an acceptable rotational range. Based on a P-value of < 0.05 and using the false discovery rate method to control Type I error, two parameters showed significant differences between normal and clinical horses. The angulation of the radial metaphysis and distal radius in relation to the angulation of the radial facet of the third carpal bone (C3) was significantly related to the occurrence of pathology in the bones of the middle carpal joint in Thoroughbred race horses. This study presented important features on DP radiographs that allowed identification of a carpal conformation associated with carpal damage in Thoroughbred race horses. Using such a highly specific, cost-effective and safe technique as a routine for examining yearling Thoroughbreds would assist in identifying horses with carpal conformation unsuited to racing.
Aiman Hussein Saleh Oheida, Abdulrhman Mohamed Salah Alrtib, Mohamed Hamrouni S. Abushhiwa, Christopher J. Philip, Helen M.S. Davies(1-2022)

Objective: Metacarpophalangeal joint (MCPJ) radiographic parameters were developed to evaluate MCPJ conformation of equine forelimbs, but the effect of joint rotation during radiography on these parameters has not been reported. The current study examined the effect of the rotation around the vertical axis of MCPJ on 27 MCPJ parameters (12 angles and 15 ratios) and identified the acceptable range of rotation at which minimal amount of changes occurred in these parameters. Design: Descriptive study Animals: MCPJs of seven right forelimbs from seven different horses with no MCPJ abnormalities. Procedures: MCPJs of seven right equine forelimbs were loaded in a load cell to obtain the normal MCPJ angle. They were frozen at −20C° and then scanned using a CT-scan machine. The collected slices were reconstructed to obtain a 3D model of MCPJs, and the dorsopalmar view at zero angle (ZDP) were identified. The view was then rotated around the vertical axis of MCPJ. Snapshots were taken for MCPJ at −10°, −5°, Zero, +5° and +10° angles. All the parameters were measured on the total 35 radiographs and statistically analysed. Differences were estimated per 5° of MCPJ rotation for all the parameters. Results:Generally, the ratio parameters were less affected than the angular parameters during MCPJ rotation. Conclusion and clinical relevance: Rotational angles of vertical ±10° from ZDP were considered as an acceptable range for reliable radiographic measurements of MCPJ parameters. Keywords Equine; fetlock; morphometry; radiology; rotation
Abdulrhman Mohamed Salah Alrtib, Aiman Hussein Saleh Oheida, Mohamed Hamrouni S. Abushhiwa, Helen M.S. Davies(12-2021)

Background: Orthopedic diseases involving the forelimb fetlock joint of horses other than those used in professional racing have not been widely reported in the literature. One of these problems is the exostosis on the proximal forelimb phalanx (P1), which has not been reported previously in Western Libya. Aim: The study aimed to investigate the prevalence of P1 exostosis in traditional equestrian horses (known locally as Sarj horses) of different breeds in Libya that participated in a special social event and described its clinical findings radiographic appearance. Methods: The current study involved 60 horses admitted to private veterinary clinics with varied fetlock orthopedic problems. The studied horses were aged between 6 and 11 years old and galloped on hard grounds. Clinical and radiographic examinations were carried out on all horses. Lateromedial radiographs for one or both forelimb fetlock joints were acquired for each horse. Results: Clinical examination revealed that 21 horses (35%) had hard non-painful swelling on the dorsal aspect of fetlock with joint stiffness during flexion. In 19 of them, the swelling was bilateral. No forelimb lameness was noticed. Radiographically, hard swelling was diagnosed as bone exostosis, with various sizes, on the proximo-dorsal aspect of P1. There was also a new bone formation on the disto-dorsal part of third metacarpal bone in two cases. Conclusion: This study has documented the first report on bone exostosis on the proximo-dorsal aspect of the forelimb proximal phalanx as a common problem in Sarj horses that galloped on hard grounds in Western Libya. Although this bone lesion did not cause lameness in all reported cases, further investigations are warranted to identify its histopathological nature, potential etiology, and proper treatment. Keywords: Exostosis, Fetlock, Forelimb proximal phalanx, Horse, Radiography.
Mohamed Hamrouni S. Abushhiwa, Taher N. Elmeshreghi, Abdulrhman Mohamed Salah Alrtib, Emad M R Bennour, Aiman Hussein Saleh Oheida(1-2022)