Cavalier King Charles Spaniel Joint Problems: What Is Usually Not the Joints

If your Cavalier has started yelping when you lift him, refusing the sofa, flinching when you touch his neck, or scratching at the air near his shoulder, the most likely explanation is not his joints. It is his skull and spinal cord. Chiari-like malformation and secondary syringomyelia are close to universal in this breed on imaging, they cause neck pain and reluctance to jump long before they cause anything that looks like a limp, and they are treated by a neurologist rather than by a supplement. This page is about telling the two apart, because in a Cavalier the orthopedic reading is the one that costs you time.

The build, and what it costs#

Every breed page on this site starts with conformation, because conformation is the only thing that is genuinely breed-specific. In a Dachshund it is the disc. In a Great Dane it is the growth plate. In a Cavalier King Charles Spaniel it is the back of the skull.

The Cavalier has a shortened, rounded head — a brachycephalic skull — but the brain inside it did not shorten by the same proportion. The result is crowding at the junction where the brain meets the spinal cord. The cerebellum is pressed against, indented by, or pushed through the opening at the base of the skull. That is Chiari-like malformation, and it obstructs the normal flow of cerebrospinal fluid at exactly the point where the fluid has to move between the skull and the spine.

Researchers have measured which parts of the skull are actually different. Using morphometric mapping on MRI scans of Cavaliers, one group found that dogs with Chiari-associated pain had the greatest flattening of the front of the brain and the shortest basioccipital bone — the small bone that forms the floor of the skull base — while dogs that went on to develop a syrinx showed the tip of the second neck vertebra sitting closer to the brainstem and a more rotated, ventrally displaced olfactory bulb.^[1] Two different shapes, two different problems: one crowds the skull base and hurts, the other narrows the fluid pathway and fills the cord.

Because when fluid cannot move freely past that junction, pressure finds somewhere else to go. It forces its way into the spinal cord itself and hollows out a fluid-filled cavity. That cavity is a syrinx, and the condition is syringomyelia.

Here is the part that matters for a page about joints. A syrinx in the neck sits alongside the sensory pathways that carry pain, temperature and itch. Damage there does not produce weakness first and it does not produce a limp first. It produces pain in the neck and shoulders, hypersensitivity to touch, and a distorted sensation the dog tries to answer by scratching at nothing. From outside, a small spaniel who will not jump onto the sofa and yelps when you scoop him up looks exactly like a small spaniel with a sore back. He is not.

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What this breed actually gets, ranked by how likely it is#

Chiari-like malformation: effectively all of them. This is not a hedge. When Dutch researchers re-evaluated 1,249 screening scans from 1,020 Cavaliers over twelve years, Chiari-like malformation was present in every single dog, leading them to conclude it has become a breed characteristic rather than a disease some Cavaliers have.^[2] That same lack of variation is why they could only estimate its heritability at 0.02 to 0.03: you cannot measure the inheritance of a trait when nothing in the population is normal.

Syringomyelia: somewhere between a third and seven in ten, depending on age. The figures you will see quoted are real, and they differ because the populations differ.

Read the first row again, because it is the most important number on this page. Those 555 dogs were not brought in because something was wrong. Their owners said they were fine. Seven in ten of the ones aged six and over had a syrinx anyway.

Patellar luxation and osteoarthritis: real, and much less common than the internet implies. In a VetCompass study of 1,875 randomly selected Cavaliers attending English primary-care practices, patellar luxation was recorded in 3.3 percent and osteoarthritis in 2.6 percent.^[5] Those are recorded veterinary diagnoses, not survey answers.

We want to be straight about the figure you will meet everywhere else. Several breed-health sites state that around 20 percent of Cavaliers have luxating patellas and that the breed is roughly nine times more likely to be affected than a crossbreed. We could not trace either figure to a peer-reviewed source, so we are not repeating it as fact. The largest primary-care study of patellar luxation in England — 210,824 dogs across 119 clinics, overall prevalence 1.30 percent — reported its highest-risk breeds as the Pomeranian, Chihuahua, Yorkshire Terrier and French Bulldog, and did not list the Cavalier among them.^[6] That is not proof the breed is unaffected. It is a reason to treat the 20 percent claim as unverified.

Hip dysplasia: no published prevalence figure for this breed that we could find. The Orthopedic Foundation for Animals maintains screening statistics by breed, built from radiographs that breeders choose to submit, and hip evaluation is one of the requirements for a Cavalier to earn a CHIC health number. We are not reproducing OFA's tables here — they ask that people read them at the source, and they are right to. Go and look. Then hold the number lightly, because a database fed by voluntary submissions is missing most of the films that looked bad on the screen.

And the one that is not orthopedic or neurological at all. In that same VetCompass cohort, a heart murmur was the single most common finding in the breed, in 30.9 percent of dogs, and cardiac disorders were the most common disorder group at 31.7 percent.^[5] A Cavalier who is slowing down, tiring on walks and reluctant to climb stairs may be telling you about his heart. That is a third possible reading of the same behaviour, and it needs a stethoscope rather than an X-ray.

When it shows up#

The timeline is the reason this gets misfiled. Orthopedic disease in small dogs is mostly a story of middle and old age. This is not.

The sentence worth carrying out of that table: arthritis does not usually start at two. If a two- or three-year-old Cavalier has stopped jumping onto the bed, the age alone should push the investigation toward the neck and away from the knees.

The earliest sign, in this breed specifically#

Generic advice tells you to watch for limping. In a Cavalier that is close to useless, because the earliest signs are about sensation, not locomotion.

The best data we have on what owners actually see comes from a 2019 study of 130 Cavaliers with MRI-confirmed Chiari-like malformation or syringomyelia, grouped by how wide the syrinx was.^[7] These are the reported frequencies:

Look at rows three and four. Reduced activity and refusing stairs and jumps — the two behaviours that send owners to the internet typing about joints — are reported by more than a third of dogs with a confirmed neurological diagnosis.

The study's most useful finding is about which signs track syrinx size and which do not. Vocalisation, spinal pain, reduced activity, behavioural change and sleep disruption occurred across every group, including the dogs with no syrinx at all. Pain in this breed is therefore not proof of a syrinx; it can come from the crowded skull base on its own. But four signs belonged almost entirely to the group with a syrinx 4 mm or wider: phantom scratching, in 67 percent of that group, weakness in 39 percent, scoliosis or a twisted neck posture in 27 percent, and deficits in postural responses. Phantom scratching was recorded in every dog whose syrinx measured 6.4 mm or more.

Phantom scratching is the one to learn#

It looks like this: the dog is walking, often on the lead, and a hind foot comes up and works rhythmically at the air beside the neck or shoulder without landing on skin. It is not the satisfied, contact-making scratch of an itchy dog.

That distinction has been imaged. Researchers compared 19 Cavaliers who phantom-scratched with 18 who did not, and found the scratchers had a large syrinx in the upper outer quadrant of the cord reaching the superficial dorsal horn at the C3 to C6 cord segments, under roughly the C2 to C5 vertebrae. The syrinx in that quadrant measured between 2.5 and 9.5 times larger in the scratchers.^[8] Their proposed explanation is that the movement is not really itch at all but a hijacked spinal reflex, closer to the automatic scratching a spinal cord can generate on its own — which would explain why a dog can phantom-scratch without appearing to be in pain, and be in pain without phantom-scratching.

A Danish and UK group then tested whether owner observations alone could predict a large syrinx, using structured interviews about 89 Cavaliers. Four things came out as significantly more frequent in dogs with a syrinx 4 mm or wider: phantom scratching, scratching at the neck or shoulder on both sides, aversion to being touched in that area, and signs that get worse when the dog is excited or upset. Combining them raised the predictive value further.^[9]

That last one is worth its own line, because it is the detail owners tend to apologise for rather than report: signs that flare when the dog is excited, anxious or aroused point toward the spinal cord, not the joints. A sore stifle does not care that the doorbell rang.

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The table to take to your appointment#

None of that is a diagnosis. It is a way of giving your vet the right five sentences in the first minute of a ten-minute appointment. Our guides to reading pain in a dog who cannot tell you and to telling a limp from weakness go through the same distinction from the other direction, without the breed lens.

“Because your dog can't tell you how much pain he or she is in.”

Screening, and what the numbers actually mean#

MRI is the only test that finds a syrinx. There is no blood test, no X-ray substitute, and no clinical sign reliable enough to make the scan unnecessary — which is precisely why the Pedersen study went looking for owner-observable predictors for situations where MRI is not available.^[9]

For breeding stock, the British Veterinary Association and Kennel Club run a formal CM/SM scheme. Chiari-like malformation is graded 0 to 2: grade 0 is no malformation, grade 1 is a cerebellum that is indented rather than rounded, grade 2 is a cerebellum impacted into or herniated through the opening at the back of the skull. Syringomyelia is graded 0 to 2 as well: 0 is normal, 1 is a central canal dilation under 2 mm, 2 is a syrinx or pre-syrinx. Results carry an age letter — c for one to three years, b for three to five, a for over five.^[10]

Those age letters are the part buyers misunderstand, so here is what they are for. A clear scan on a young dog is a much weaker guarantee than a clear scan on an older one, because the syrinx may simply not have formed yet. That is the whole meaning of the age gradient: 25 percent at one year, 70 percent by six.^[3] A grade 0 with a c beside it means "clear at an age when clear is common." A grade 0 with an a beside it means something.

Two further honesty notes on screening.

First, it is not obviously working yet at population level. The Australian study looked at 386 dogs scanned across sixteen years and found no significant change in prevalence or severity over that period, despite voluntary screening running throughout, and concluded that scanning beyond three years of age and stricter breeding decisions would be needed to shift it.^[4] The Dutch analysis found the classic BVA grading gave a heritability of 0.13 for syringomyelia, while measuring central canal dilation exactly gave 0.30 — meaning selection responds better to a measurement than to a grade.^[2]

Second, a small practical finding with an outsized effect. In that Dutch series, microchip artefacts obscured the images in 60 percent of scans, and the authors' explicit recommendation was to site microchips somewhere other than the standard neck position in breeds prone to syringomyelia.^[2] If you are buying a Cavalier puppy, that is a sentence worth saying to the breeder and to your own vet before the chip goes in.

The gap between imaging and the medical record is worth naming too. In the VetCompass primary-care cohort, MRI-confirmed syringomyelia, Chiari-like malformation, or both were recorded in about 2 percent of Cavaliers, with syringomyelia ranking 28th among recorded diagnoses.^[5] Those two figures — around half on MRI, around 2 percent on the chart — are not contradictory, and it would be dishonest to present them as though they were. Most Cavaliers never have an MRI, and a large number of dogs with a syrinx never develop signs that trouble anyone. What the gap does tell you is that your dog's clinical record is not evidence of absence. Nobody looked.

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What actually helps#

We are not going to sell you anything on this page. There is no bed, no supplement, no brace and no joint injection that treats a crowded skull base or a cavity in the spinal cord, and a Cavalier who is put on a glucosamine product while the real problem goes unexamined has lost months, not just money. That is the single most useful thing this page can say.

What does help, in order:

A neurological examination, described correctly. Book the appointment and lead with the scratching, the yelping and the touch aversion — not with "he's not jumping any more." Ask directly whether the signs could be neurological. If the picture fits, ask about referral to a veterinary neurologist. Our list of questions to ask a specialist is written for orthopedic consultations, but the structure of it transfers.

Video, taken before you go. Phantom scratching is intermittent and almost never obliges in the consulting room. Thirty seconds of your dog walking on a lead, filmed from the side, is worth more than any description you can give. Film it on a normal walk, on flat ground.

A harness instead of a neck collar. This is standard advice from neurologists working with the condition, and the mechanical logic is obvious in a dog whose problem sits at the craniocervical junction and who flinches when touched at the neck. We want to be accurate about its status: we could not find any trial comparing harnesses with neck collars in affected dogs, so this is reasoned clinical practice rather than tested intervention. It costs very little to follow and there is no plausible downside.

Removing the jumps rather than asking for them. Steps or a ramp to the sofa and bed take the repeated impact out of the day. That is worth doing for a Cavalier whether the underlying problem turns out to be neurological or orthopedic, and it is the one piece of household equipment that earns its place in this breed. A blanket over a slippery floor does similar work for free; our floor traction guide covers the cheap version properly.

Lean body condition. This is the largest modifiable factor in genuine joint disease and it is free. It will not shrink a syrinx. Say both of those things at once and you have the truth.

Medication is the vet's decision, and the evidence is thinner than you would hope. Neuropathic pain in this condition is generally managed with prescription drugs, and we are not going to name doses. What we will report is the state of the evidence: the most relevant recent trial compared amitriptyline against gabapentin in 90 dogs with Chiari-like malformation or syringomyelia, and found amitriptyline moderately but not statistically significantly better, with the addition of furosemide bringing no benefit. Those 90 dogs were Pomeranians, not Cavaliers.^[11] That is the best comparative drug evidence in this area, and it is in a different breed and did not reach significance. Anyone who tells you confidently which drug is best is going beyond what has been shown.

Surgery exists, and its results are honest rather than triumphant. Foramen magnum decompression aims to relieve the crowding at the skull base. In the longest-followed series we could verify, 15 Cavaliers had cranial cervical decompression: 80 percent improved and 20 percent were unchanged, with low mortality and morbidity — but the syrinx did not collapse or resolve on follow-up imaging, and 7 dogs, 47 percent, deteriorated again between 0.2 and 2.3 years after the operation, on average at 1.3 years.^[12] That is a small, old series, and technique has moved since. It is also the number a family deserves before they make the decision: most dogs improve, and roughly half slip back within a couple of years.

What we still do not know#

We would rather write this section than leave the gaps as implied confidence.

Nobody has published how often Chiari-like malformation or syringomyelia in this breed is first treated as an orthopedic or dermatological problem. The mechanism for the confusion is well documented and the sign frequencies above make it near-inevitable, but the misdiagnosis rate itself is not a number anyone has measured, and we are not going to invent one.

There is no published prevalence figure for hip dysplasia in Cavaliers that we could locate in the peer-reviewed literature. The commonly quoted patellar luxation figure of around 20 percent is likewise untraceable to a primary source.

And the biggest one: nobody can yet tell you which asymptomatic Cavalier with a syrinx will develop signs and which will live a full life untroubled by it. Age raises the odds of having a syrinx and size raises the odds of the myelopathy signs, but the individual prediction does not exist.

Where to go next#

If the picture on this page fits your dog, the next click is a phone call, not another article. If it does not — if your Cavalier is genuinely lame, favouring one limb, worse on cold mornings and better once he is moving — then the joint pages are the right ones: arthritis in dogs for the mechanics and management, hip dysplasia for the hip specifically, and muscle wasting in one back leg for the measurement that tells you how long it has been going on.

For a sense of how a spinal problem in a small breed unfolds and what the urgency looks like, IVDD in dogs and our Dachshund page are the closest neighbours to this one, though the disease is different in kind.

What to do this week#

Film thirty seconds of your dog walking on a lead, from the side, on flat ground. Do it twice on different days, because the scratching does not perform on demand.

Then write down four answers, because these are the four that were shown to predict a large syrinx: does he scratch without making contact; does he scratch at both sides of the neck or shoulder; does he object to being touched there; and do the signs get worse when he is excited or upset.^[9]

Then book the appointment and open with those four answers rather than with the sofa. Swap the neck collar for a harness on the way.

The delay in this breed is rarely caused by an owner who was not paying attention. It is caused by an owner who was paying very close attention to the wrong body part, because the behaviour genuinely looks like a sore back. Naming it correctly is most of the work, and it is work you can do tonight with a phone camera and a piece of paper.

Sources#

1. Knowler SP, Cross C, Griffiths S, McFadyen AK, Jovanovik J, Tauro A, Kibar Z, Driver CJ, La Ragione RM, Rusbridge C. "Use of Morphometric Mapping to Characterise Symptomatic Chiari-Like Malformation, Secondary Syringomyelia and Associated Brachycephaly in the Cavalier King Charles Spaniel." PLoS ONE. 2017;12(1):e0170315. doi:10.1371/journal.pone.0170315 — 130 dogs in the hindbrain study, 72 in the whole-brain study; the CM-pain group showed the greatest rostral forebrain flattening and the shortest basioccipital bone; the SM group showed proximity of the dens and a smaller, more ventrally rotated olfactory bulb.
2. Wijnrocx K, Van Bruggen LWL, Eggelmeijer W, Noorman E, Jacques A, Buys N, Janssens S, Mandigers PJJ. "Twelve years of chiari-like malformation and syringomyelia scanning in Cavalier King Charles Spaniels in the Netherlands: Towards a more precise phenotype." PLoS ONE. 2017;12(9):e0184893. doi:10.1371/journal.pone.0184893 — 1,249 screenings of 1,020 dogs re-evaluated; CM present in all dogs; SM in 39% with a clear age effect; middle ear effusion 19–21% under three years and 32–38% over three; microchip artefacts noted in as much as 60%, prompting a recommendation to place chips elsewhere in susceptible breeds; heritability of CM 0.02–0.03, SM 0.13 by the classical BVA/KC method versus 0.30 for exact central canal dilation measurement.
3. Parker JE, Knowler SP, Rusbridge C, Noorman E, Jeffery ND. "Prevalence of asymptomatic syringomyelia in Cavalier King Charles spaniels." Veterinary Record. 2011;168(25):667. doi:10.1136/vr.d1726 — 555 Cavaliers declared by their owners to be showing no clinical signs; only increased age had a significant effect; prevalence 25% at 12 months rising to a peak of 70% at 72 months and older.
4. McLeay L, Child G. "Syringomyelia in Australian Cavalier King Charles spaniels: prevalence and changes over 16 years of magnetic resonance imaging screening." Australian Veterinary Journal. 2026;104(1-2):50-56. doi:10.1111/avj.70013 — MRI screening data from 386 Australian CKCS between 2008 and 2024; syringomyelia detected in 50.5%; prevalence increased significantly with age; black and tan dogs more severely affected than Blenheim; no significant change in prevalence or severity across the 16-year period.
5. Summers JF, O'Neill DG, Church DB, Thomson PC, McGreevy PD, Brodbelt DC. "Prevalence of disorders recorded in Cavalier King Charles Spaniels attending primary-care veterinary practices in England." Canine Genetics and Epidemiology. 2015;2:4. doi:10.1186/s40575-015-0016-7 — 1,875 CKCS randomly selected, 1,749 with clinical records; heart murmur most common specific finding at 30.9%; patellar luxation 3.3%; osteoarthritis 2.6%; MRI-confirmed syringomyelia, CM or both recorded in approximately 2%; cardiac the most common disorder group at 31.7%.
6. O'Neill DG, Meeson RL, Sheridan A, Church DB, Brodbelt DC. "The epidemiology of patellar luxation in dogs attending primary-care veterinary practices in England." Canine Genetics and Epidemiology. 2016;3:4. doi:10.1186/s40575-016-0034-0 — 210,824 dogs across 119 clinics; overall patellar luxation prevalence 1.30%; highest breed odds ratios reported for Pomeranian (6.5), Chihuahua (5.9), Yorkshire Terrier (5.5) and French Bulldog (5.4); the Cavalier King Charles Spaniel was not among the breeds reported with elevated odds.
7. Rusbridge C, McFadyen AK, Knower SP. "Behavioral and clinical signs of Chiari-like malformation-associated pain and syringomyelia in Cavalier King Charles spaniels." Journal of Veterinary Internal Medicine. 2019;33(5):2138-2150. doi:10.1111/jvim.15552 — 130 dogs grouped by maximum syrinx transverse diameter; vocalisation 65.4%, spinal pain 54.6%, reduced activity 37.7%, reduced stairs/jumping 35.4%, touch aversion 30.0%, head scratching/rubbing 28.5%, altered emotional state 28.5%, sleep disruption 22.3%; phantom scratching, weakness, scoliosis and postural deficits confined largely to the group with syrinx ≥4 mm; phantom scratching recorded in all dogs with syrinx width ≥6.4 mm; head scratching inversely associated with syrinx size (P = .005).
8. Nalborczyk ZR, McFadyen AK, Jovanovik J, Tauro A, Driver CJ, Fitzpatrick N, Knower SP, Rusbridge C. "MRI characteristics for 'phantom' scratching in canine syringomyelia." BMC Veterinary Research. 2017;13(1):340. doi:10.1186/s12917-017-1258-2 — 19 Cavaliers with phantom scratching compared with 18 without; phantom scratching associated with a large dorsolateral syrinx extending to the superficial dorsal horn at C3–C6 spinal cord segments; estimated dorsal quadrant syrinx sizes 2.5 to 9.5 times larger in affected dogs; the authors propose the behaviour resembles fictive scratch and may be distinct from neuropathic pain.
9. Pedersen TR, Bach MBT, Stougaard CL, Gredal H, Rusbridge C, Finnerup NB, Berendt M. "Clinical predictors of syringomyelia in Cavalier King Charles Spaniels with Chiari-like malformation based on owners' observations." Acta Veterinaria Scandinavica. 2024;66:5. doi:10.1186/s13028-024-00725-1 — 89 CKCS classified by MRI into CM without syrinx or <2 mm (n = 13), small syrinx 2.00–3.99 mm (n = 26) and large syrinx ≥4 mm (n = 50); phantom scratching, bilateral neck or shoulder scratching, aversion to touch in that area and exacerbation with emotional arousal were significantly more frequent in dogs with a large syrinx, with combined signs increasing predictive value.
10. British Veterinary Association / Kennel Club. "Chiari Malformation/Syringomyelia Scheme." bva.co.uk — CM graded 0 (no malformation), 1 (cerebellum indented, not rounded) and 2 (cerebellum impacted into or herniated through the opening at the rear of the skull); SM graded 0 (normal), 1 (central canal dilation under 2 mm) and 2 (syrinx or pre-syrinx); age qualifiers a (over five years), b (three to five years), c (one to three years).
11. Maat RT, van Heusden K, Hoogervorst-Spek L, Płonek M, Mandigers PJJ. "The Effectiveness of Amitriptyline and Gabapentin in Treating Pomeranians with Chiari-like Malformation and/or Syringomyelia." Animals. 2025;15(7):992. doi:10.3390/ani15070992 — 90 Pomeranians, 62 treated with amitriptyline and 28 with gabapentin; amitriptyline showed a moderate but not statistically significant more favourable effect on CM/SM pain; addition of furosemide where pre-syrinx was present did not improve outcomes. Conducted in Pomeranians, not Cavaliers.
12. Rusbridge C. "Chiari-like malformation with syringomyelia in the Cavalier King Charles spaniel: long-term outcome after surgical management." Veterinary Surgery. 2007;36(5):396-405. doi:10.1111/j.1532-950X.2007.00285.x — 15 Cavaliers undergoing cranial cervical decompression; all dogs either improved (80%) or were unchanged (20%); syringomyelia persisted on follow-up imaging; 7 dogs (47%) subsequently deteriorated between 0.2 and 2.3 years after surgery, mean 1.3 years.

The hero illustration on this page is a generated likeness of the breed, not a photograph of a specific dog, and nothing here should be read as a judgement about any individual dog's conformation.

This article is educational and does not replace veterinary advice. Chiari-like malformation and syringomyelia can only be confirmed by MRI, and treatment decisions — including whether to scan at all — belong to a veterinary neurologist who has examined your dog.