A giraffe’s hoof hides much of the machinery that makes a step possible. Inside are bones, joints, tendons and layers of tissue that anchor the hoof wall. Damage in any of these places can be difficult to disentangle from changes nearby. An X-ray helps reveal the interior, but it compresses overlapping structures into one view. Understanding what has happened inside a troubled foot requires another level of detail.
Liza Dadone, radiologist Seng Wai Yap and their colleagues brought two kinds of evidence together in a 2026 study in PLOS One. They scanned preserved feet from giraffes that had died, then examined selected tissues microscopically. The scans located abnormalities throughout the foot; the tissue sections showed disrupted attachments, altered bone and degeneration within tendons and ligaments. Together, they made it possible to see a damaged foot as a set of connected structures.
Looking through the hoof
Each giraffe foot has two weight-bearing digits, corresponding to two toes. Each contains a bone enclosed by the hoof, called the distal phalanx. Tendons help control movement, ligaments hold joints stable, and interlocking tissue layers called laminae help anchor the hoof wall to the structures beneath it. Their arrangement matters because the animal’s weight must pass through a foot that remains both supportive and able to move.
Conventional radiographs are useful for examining this framework, but one bone can obscure part of another. Computed tomography, or CT, produces a series of cross-sectional images that can be viewed in different planes. A researcher can follow a defect through the bone or locate a mineral deposit within a tendon without the same overlap.
Scanning the feet of a living adult giraffe is impractical in most clinical settings. The team instead assembled 73 preserved lower limbs from 21 giraffes at 12 North American zoos. The animals had died or been euthanized for their own health and welfare reasons between 2004 and 2023; none was killed for the study. The available feet contained 146 digits.
This collection was especially useful for studying established damage. Many of the adults had histories of lameness, hoof overgrowth or suspected foot disease. The selected group contained three juveniles under three years old and 18 adults aged 11 or older. Its findings describe the lesions in those animals, rather than how common foot disease is among giraffes in zoos today.
Yap assessed the scans without the animals’ clinical histories. A veterinary pathologist examined selected tissue samples from six of the giraffes. That second stage, histopathology, could test whether a suspicious appearance on a scan corresponded to recognizable tissue damage. It was targeted examination of particular sites, rather than a microscopic survey of every digit.
Three forms of damage inside the foot
The clearest contribution of combining the methods is visible in the paper’s paired scans and tissue images. They connect a change in shape or density with a change in the material doing the supporting.
In the hoof attachment, CT showed irregular margins where the laminae should form an orderly arrangement. Under the microscope, affected laminae were widened, blunted and less regularly aligned, with larger spaces between them. These changes were consistent with chronic laminitis, injury to the hoof’s laminar tissues. The finding concerns a connection that helps keep the hoof wall securely attached as the foot bears weight.
Most of these changes were mild on the team’s CT grading scale: 57 of the 64 digits with laminar abnormalities received the mildest positive score. That distinction matters. Detecting an abnormal attachment does not mean that every affected foot has suffered severe structural failure, and the clinical meaning of mild scan changes remains uncertain.
Within the distal phalanx, a different pattern appeared. CT revealed irregular loss of bone and thinning of its outer layer, categorized as pedal osteitis. Microscopy showed that the internal bony struts, which form a supporting network, were thinned and disorganized in affected samples. Areas of bone removal and increased porosity helped explain why the scan looked abnormal. The damage involved the bone’s architecture, rather than merely a change in its outline.
Tendons and ligaments added a third part of the story. CT detected mineral deposits in some of these normally soft structures. Tissue examination found disrupted collagen fibres, fibrosis—the formation of scar-like connective tissue—and areas where cartilage or bone had developed within affected tendons. Those findings supported longstanding degeneration in structures that normally transmit force or stabilize joints.
Figures 3–5 in the paper show these comparisons directly. The microscope does more than magnify the scan: it reveals what kind of tissue alteration lies behind it.
The two methods also have different blind spots. CT is less effective at revealing subtle soft-tissue changes that lack mineral deposits. These limbs were scanned frozen, which can change tissue appearance. Because the microscope samples were selected and limited, they corroborate particular lesions without establishing how reliably CT detects every form of foot disease.
Fractures belonged to a wider pattern of bone damage
All 18 adults had pedal osteitis and bony outgrowths around the lowest toe joint in at least one digit. Those changes were absent from the three juveniles. This contrast fits the authors’ interpretation of a chronic process, but the missing ages between three and ten years leave a large gap: the study did not follow a healthy young foot as lesions developed.
Fractures provided a more specific connection. The bone inside the hoof was fractured in 25 of the 146 digits, belonging to nine giraffes. Every fractured digit also showed pedal osteitis. Bone damage was much more widespread than fracture, however: it occurred in 117 digits overall, including 92 without a fracture.
That comparison suggests why bone quality deserves attention. The scans and tissue samples showed ways in which the distal phalanx’s supporting structure could be compromised, and the fractured digits tended to have more severe osteitis scores. A bone with less intact structure may tolerate loading differently. The authors suggest that progressive damage could make fracture more likely.
The images capture an endpoint, so the sequence remains unresolved. A fracture could also alter loading and contribute to later degeneration. Several measurements came from the same animal, and the statistical analyses of digits did not account fully for that grouping. The association identifies a plausible relationship to follow over time; it does not provide an individual animal’s fracture risk.
The broader pattern reinforces this point. Fractured digits frequently also contained abnormalities in neighbouring joints and bones. Looking for a single lesion to explain the whole foot would miss part of the evidence.
A small bone draws attention to the front feet
One structure stood out in the comparison of front and hind feet: the navicular bone, a small bone near the back of each digit associated with the deep flexor tendon and nearby supporting tissues. CT revealed changes including erosion, unusually dense bone and cavities within it.
Eighteen giraffes had both front and hind feet available. Among these animals, 14 had navicular changes in at least one front foot, compared with seven in at least one hind foot. Comparing the two ends of the same animals made this a useful clue about where lesions were concentrated.
Dadone and colleagues suggest that differences in mechanical loading could help explain the pattern. They also draw attention to navicular changes occurring alongside degeneration in the nearby tendon and ligaments. Their proposal is that this whole region deserves closer attention in investigations of chronic foot problems.
The study did not measure forces during walking, so it cannot establish why the front feet differed. Its contribution is to identify a specific anatomical region for further investigation, with CT resolving details that overlapping radiographic views can obscure.
What comparatively intact feet add
Interpreting a damaged giraffe foot is easier when researchers know what its tissues normally look like. In a separate 2025 study, Dadone, Steve Foxworth, Jacqueline Goedhals and colleagues examined foot anatomy from six adult southern giraffes living on a South African reserve. The animals had been culled for reserve management before the research project was conceived.
Microscopic work on one front-foot digit from each animal showed orderly laminar attachments and a digital cushion containing regions rich in fat and fibrous tissue. The cushion sits behind the deep flexor tendon; its organization helps researchers understand the structures involved in distributing loads through the foot. No significant lesions were detected in the bone and tendon samples examined.
That anatomical reference gives the 2026 images something concrete to be compared with. It does not establish a disease rate for wild giraffes, and it is not an age-matched control group: the reserve animals’ exact ages were unknown, and sampling covered limited sites. Its value is showing tissue arrangements that can be contrasted with disruption.
An earlier study adds a different perspective. During a 2017 conservation translocation in Uganda, Dadone and colleagues obtained foot radiographs from 24 apparently healthy young Nubian giraffes. Three had mild pedal osteitis, while no distal-phalanx fractures were detected. These were selected living animals examined with field radiography, whereas the 2026 collection largely comprised older animals with foot concerns examined after death. The two studies help define questions about age, environment and detection; they cannot isolate the effect of zoo management.
Our giraffe health guide places foot imaging alongside other forms of assessment. This new work supplies the internal pathology behind one part of that wider picture.
Following the changes back into living animals
The practical opportunity lies in connecting this detailed view after death with observations that are feasible during life. The authors call for studies following giraffes over time under contemporary care conditions. Repeated radiographs and hoof observations, considered alongside veterinary records, could establish whether particular changes precede more extensive damage.
One useful question is whether changes in the hoof bone appear before fractures. Following the same feet would add the missing order of events, while comparable records from animals without foot concerns would help separate disease progression from variation associated with age. A scan collected only after death cannot supply either comparison on its own.
Another is how hoof shape and the surfaces an animal uses relate to changes inside its feet. The authors discuss altered loading, diet and historical care practices as possible influences. Those records were too inconsistent in this cohort to test the explanations. Tracking them alongside repeated observations would let researchers assess which relationships persist when age and other differences are considered.
The immediate achievement is a more detailed account of what an affected foot contains. The team connected irregular scan appearances with damaged hoof attachments, altered bone and degenerating soft tissues. That gives future work a clearer task: determine which observable changes signal a developing problem early enough to improve assessment and care.
Sources
Focal research: Liza Dadone, Steve Foxworth, Matthew S. Johnston, Sushan Han, Priya Bapodra-Villaverde, Erika Crook, Jill Erzar, John Griffioen, Kimberly L. Rainwater, Shirley LLizo, Joseph A. Smith, Kami Alvarado, Logan Wood, Heather Schwartz, Trevor T. Zachariah and Seng Wai Yap (2026). Postmortem computed tomography and histopathology of distal limb lesions in giraffe (Giraffa spp.) under managed care. PLOS One 21(6), e0352507. Published 26 June 2026. DOI: 10.1371/journal.pone.0352507. Read the full paper.
Anatomical reference: Liza Dadone, Steve Foxworth, Jacqueline Goedhals, Sushan Han, Priya Bapodra-Villaverde, Seng Wai Yap, Thato Radile and Francois Deacon (2025). Anatomy and baseline histology of the hoof capsule, corium, and digital cushion in free-ranging southern giraffe (Giraffa giraffa). PLOS One 20(12), e0339972. DOI: 10.1371/journal.pone.0339972.
Living wild giraffes: Liza Dadone, Steve Foxworth, Robert Aruho, Amy Schilz, Andrea Joyet, Myra Barrett, Peter Morkel, Garrett Crooks, Julian Fennessy and Matthew S. Johnston (2021). Foot shape and radiographs of free-ranging Nubian giraffe in Uganda. PLOS One 16(12), e0252929. DOI: 10.1371/journal.pone.0252929.
