Purchase X-Rays and the German Röntgen Classes
Contents
Purchase radiographs are a standardised set of x-ray views taken at the pre-purchase examination — from small sets of the feet, fetlocks and hocks to large sets of eighteen or more views adding stifles, back and neck. The German market historically graded them into classes I–IV (the horse’s “TÜV”), a system officially replaced in 2018 by descriptive, risk-based reporting — but the class vocabulary survives in adverts and conversations, so buyers need to speak both. And they need the system’s most important caveat before any of it: radiographs show structure, not pain, in either direction.
X-rays are the part of the pre-purchase examination that generates the most paper, the most negotiation and the most misunderstanding. This page covers the sets, the classification history, the practical rights and windows, and how the dossier system works at auctions — leaving the interpretation of specific findings (OCD, kissing spines, navicular changes) to common findings decoded.
What gets x-rayed: the standard sets
There is no single mandatory set; clinics offer tiers, and the buyer chooses against price and purpose. The conventional architecture:
Small set (~10–12 views). The classic core: lateral views of all four feet including the navicular region, front fetlomps, and the hocks — the regions where findings most often carry consequences and where the historical German standard sets concentrated.
Medium set (~14–18 views). Adds oblique projections of fetlocks and hocks and typically the stifles — a region increasingly included as its findings gained attention in sport-horse practice.
Large set (18–24+ views). Adds the back (spinous processes, for the kissing-spines question that dressage buyers reasonably ask) and often the neck (cervical facet joints, a topic of growing veterinary attention in dressage horses). Standard at high prices and at the elite auctions, whose dossiers are typically large-set.
Scaling logic mirrors the exam itself: the set should grow with the price and the ambition. A practical floor for a dressage purchase of any seriousness is the small-to-medium set; the marginal cost of additional views while the horse and machine are already together is modest against the information.
The German classes — and what replaced them
For roughly two decades, German purchase radiography ran on the Röntgenleitfaden’s class system, and its vocabulary colonised the whole European market:
| Historical class | Meaning (paraphrased) |
|---|---|
| Class I | Ideal findings — no deviations from the norm |
| Class II | Findings deviating from the ideal, but of no expected clinical significance |
| Class III | Findings where clinical significance is possible but not probable |
| Class IV | Findings where clinical significance is probable |
(Intermediate steps such as II–III were common in practice.) A “class I–II horse” became shorthand for clean x-rays, sellers priced on it, and the classes still appear in adverts today.
The 2018 change. The revised German guideline abolished the classes in favour of descriptive, risk-based reporting: the veterinarian describes each finding and assesses its risk for the intended use, rather than stamping the horse with a grade. The professional reasoning behind the change is worth a buyer’s understanding, because it is a free education in how to read any report: the classes implied a precision the science does not support — the correlation between many radiographic findings and future clinical problems is weak and use-dependent, identical images can mean different risks for different careers, and the single grade invited exactly the pass/fail thinking the examination is not built for.
The buyer’s bilingual rule. When a seller says “TÜV I–II”, translate it as a claim that the report described no significant findings — then ask for the report and images themselves, because the claim is a summary of a document you are entitled to read. When your own vet’s report arrives in descriptive form, resist asking “so what class is that?”; ask instead the question the modern format is designed to answer: what is the risk of this finding for this horse in the career I have described?
Practical rights and mechanics
Who owns the images. The party who commissioned and paid for them — your PPE set is yours; a seller’s existing set is theirs, shared by consent (and quality sellers share readily, since current images defend asking prices, as the price guide notes). Auction dossier images are provided to registered bidders under the auction’s conditions.
Second readings. Any set can — and for remote buyers, always should — be re-read by the buyer’s own veterinarian: interpretation genuinely varies between readers, and two readings convert one opinion into a range (buying from video makes this mandatory practice). Digital DICOM files transfer trivially; ask for them, not screenshots.
Validity windows. Radiographs are a snapshot, and the market convention treats a set as current for roughly six months — older sets are history, useful for comparison (“was this finding present two years ago?”) but not a substitute for current images on a horse being sold today. A seller offering only an old set for a current sale is making an economy the buyer should decline to share.
Sedation and logistics. Horses are lightly sedated for radiography as routine; the session takes an hour or two at a clinic, longer with portable equipment at a yard. Clinic sessions generally produce better images and easier storage/transfer — one reason the exam location question in the PPE guide leans toward clinics for full workups.
The stored-blood pairing. Radiography day is blood day: the stored sample drawn alongside the images covers the possibility that what moved soundly through the exam was pharmacologically assisted — the two protections are a set.
What x-rays cannot tell you
The caveat that governs everything above, in both directions:
Findings without problems. Large numbers of sound, performing horses carry radiographic findings that never trouble them — surveys of warmblood populations and the entire logic of the 2018 reform rest on this fact. An image is not a prognosis; a finding is a question for clinical correlation, use-assessment and, sometimes, a price conversation (common findings, negotiation).
Problems without findings. The inverse is equally true and less advertised: soft-tissue structures — the suspensory apparatus that dressage careers most often strain — barely register on radiographs, and pain has no pixel. “Clean x-rays” is a statement about bone architecture on a given day, not a warranty of soundness; the clinical examination, the flexions, the lunge on the hard circle and the horse’s verifiable history carry information no image contains.
Which returns to the section’s organising idea: the whole examination, images included, prices risk. It does not abolish it.
Frequently asked questions
What x-ray class is acceptable when buying a horse? Under the historical German system, classes I–II were the market’s “clean” standard and III the negotiation zone — but the classes were officially retired in 2018 for descriptive, risk-based reporting, and the modern answer is use-dependent: the question is not the grade but each finding’s assessed risk for your intended career, discussed with the examining vet.
How long are purchase x-rays valid? By market convention, roughly six months — beyond that, a set documents history rather than the horse being sold today. Older sets retain comparison value (showing whether a current finding is old and stable or new), which is a reason to request them alongside, not instead of, current images.
Do clean x-rays guarantee soundness? No. Radiographs show bone structure, not pain, and barely see the soft tissues where dressage careers most often strain. “Clean” images support the price and reduce specific risks; the clinical examination, the horse’s history and the stored blood sample cover what the images cannot.
Should I x-ray the back and neck? Increasingly common for dressage purchases at meaningful prices: spinous-process views address the kissing-spines question directly, and cervical views a region of growing veterinary attention. Two calibrations: radiographic back findings are frequent in symptom-free horses (clinical correlation decides), and the added views cost little once the session exists — the information-per-euro is favourable.