The navicular bone is a small, boat-shaped bone located in the hoof of a horse, specifically situated behind the coffin bone and beneath the deep digital flexor tendon. It plays a role in the biomechanics of the equine foot by acting as a fulcrum for the deep digital flexor tendon, aiding in the horse's movement and weight distribution. The navicular bone is part of the navicular apparatus, which includes surrounding ligaments and the bursa, a fluid-filled sac that reduces friction. Issues with the navicular bone and associated structures can lead to a condition known as navicular syndrome, which is characterized by lameness and pain in the front feet. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, function, and pathophysiology of the navicular bone, as well as diagnostic and treatment options for navicular-related conditions in horses.
Rowan C, Puggioni A, Hoey SE, O'Leary JM, Kearney C, Connolly SE, Skelly C.The requirement to pack the sulcus of the equine foot as an aid to diagnostic interpretation before acquisition of dorsoproximal-palmarodistal oblique projections is debatable. The purpose of this study was to investigate the benefit of packing the sulcus in the assessment of normal anatomy. 23 cadaver limbs were radiographed in a podoblock (https://www.podoblock.com/products-page/podoblock/podoblock/) A non-packed image (NP) and a packed image (P) of the same foot were acquired. The image quality of P was graded against the reference NP by five observers, where -1=P was superior, 0=no differe...
Rijkenhuizen AB, Nèmeth F, Dik KJ, Goedegebuure SA, Van den Brom WE.Clinical, radiographical, scintigraphical and histological effects on the navicular bone after resection of the medial and lateral palmar digital arteries in the pastern of one forelimb in ponies are evaluated. The acute disruption of the main blood supply of the distal extremity causes lameness due to the suddenness of the resection in which the collateral circulation is insufficiently developed. Because of the compensatory collateral circulation, no permanent symptoms of ischaemia occur despite the partial resection of both palmar digital arteries. Histologically the percentage of relative o...
Yorke EH, Judy CE, Saveraid TC, McGowan CP, Caldwell FJ.Distal border fragments of the navicular bone are increasingly being detected due to the improved capabilities of magnetic resonance imaging (MRI), but their clinical significance remains unclear. The purpose of this retrospective study was to describe the location, size, and frequency of fragments in a cohort of horses presented for MRI of the foot and to compare MRI findings with severity of lameness. Archived MRI studies and medical records were searched from March 2006 to June 2008. Horses were included if a distal border fragment of the navicular bone was visible in MRI scans. Confidence ...
Fuss FK.The horse's navicular bone is located inside the hoof between the deep flexor tendon (DDFT) and the middle and end phalanges. The aim of this study was to calculate the stress distribution across the articular surface of the navicular bone and to investigate how morphological variations of the navicular bone affect the joint forces and stress distribution. Joint forces normalised to the DDFT force were calculated from force and moment equilibria from morphological parameters determined on mediolateral radiographs. The stress distribution on the articular surface was determined from the moment ...
Larsen EA, Williams MR, Schoonover MJ, Jurek KA, Young JM, Duddy HR.Navicular syndrome is a common cause of forelimb lameness in horses. Beyond changes to the navicular bone itself, horses with a clinical diagnosis of navicular syndrome often have pathology associated with other components of the navicular apparatus, including the navicular bursa, deep digital flexor (DDF) tendon, collateral sesamoidean ligaments, and impar ligament. Palmar digital neurectomy (PDN) is often used as a salvage procedure for horses diagnosed with navicular syndrome that become unresponsive to medical management. There are many potential complications associated with PDN, some of ...
Pudert T, Fries GF, Lotz H, Röcken M, Cruz AM.To assess the use of a newly developed aiming compression device (ACD) for screw insertion in non-fractured navicular bones (NB) in cadavers. Methods: Cadaveric study. Methods: A total of 10 cadaveric front limbs of adult horses. Methods: Placement of a 3.5 mm cortical screw in non-fractured NB under radiographic guidance was performed in 10 cadaver limbs in a standing position. An ACD was used to stabilize the NB and to guide the drilling process. Preparation and surgical time as well as the number of radiographic images were noted. A postoperative scoring system was used to assess screw pl...
Stutsel M, Jordan L, Smith C, Lee WY, Symonds N, Bell R, Young A.Foot-related lameness is common in Standardbred and Thoroughbred racehorses. Magnetic resonance imaging (MRI) provides information on both the soft tissue and osseous structures of the distal extremity. The aim of this study was to determine whether abnormalities identified on distal limb MRI differed between these two racehorse populations. Methods: The records of Standardbred and Thoroughbred racehorse distal extremity MRI examinations conducted at Camden Equine Centre and Ballarat Veterinary Practice between 2013 and 2023 were retrieved. Horses were included if pain causing lameness had bee...
Maleas G, Werpy N, Joostens Z, Bladon B, Gerlach K, Mageed M.Navicular intrabursal pathology (NIP) is a common cause of forelimb lameness in horses. An accurate diagnosis of which structure is involved is essential for therapy and prognosis. Objective: The study aimed to compare the diagnostic performance of ultrasonography, bursography and standing magnetic resonance (MRI) imaging as diagnostic tools of the proximal NIP using bursoscopy as the gold standard. Methods: Prospective blinded study. Methods: A total of 21 feet from 17 horses were included. The feet underwent ultrasonography, followed by MRI, and thereafter bursography and bursoscopy. The i...
Folgmann MS, Stock KF, Feige K, Delling U.Current studies on the health status of young German Warmblood stallions are lacking. Objective: To evaluate the prevalence of radiographic findings at licensing examinations of Warmblood candidate stallions and quantify the environmental influences on the distribution of recorded findings. Methods: In this retrospective observational study, records of 1693 radiographic examinations performed on 1678 German Warmblood stallions presented for licensing in 2018-2020 were reviewed. Data were provided by all German Warmblood horse-breeding associations and their official veterinarians. The collecti...
Giessen EJM, Stas EKL, Grinwis GCM, Veraa S.A 3-month-old Friesian colt presented with severe, progressive distal limb lameness in two limbs. Radiographic and postmortem full-body CT imaging revealed severe articular deforming osteolysis and osteoproliferation at the dorsodistal navicular bone margin and the adjacent distal phalanx proximo-palmar/proximo-plantar margin in two limbs, with the remainder of the distal interphalangeal joint being unaffected. Multiple other joints showed small osteolytic subchondral defects. Postmortem histopathological examination confirmed focal joint disease of both distal interphalangeal joints, without ...
Marcatili M, Kalinovskiy A, Christoph L.To describe the additional information provided by computed tomography (CT) in planning and assisting repair of comminuted fractures of the middle phalanx (MP) in Warmblood horses. Methods: Case series. Methods: Six adult Warmblood horses. Methods: The case records of horses undergoing CT examination prior to internal fixation of comminuted MP fractures were reviewed. All horses underwent radiographic and preoperative CT examination. A standardized fast protocol (SFP) to assess CT images was used. Surgical repair consisted of fracture repair and proximal interphalangeal joint arthrodesis using...
Honnas DH, Fiske-Jackson AR, Fulkerson CV, Wilhite DR.An injury of a tendon or ligament of the equine foot is frequently a cause of lameness. The optimal radiographic projections delineating the entheses of five commonly injured tendons and ligaments of the foot should be described. Methods: The entheses of the collateral ligaments of the distal interphalangeal joint, the collateral sesamoidean ligaments of the navicular bone, the deep digital flexor tendon, the common digital extensor tendon and the distal sesamoidean impar ligament were isolated from a thoracic foot of three cadavers. Three standard radiographic projections (60-degree, dorsopro...
