40 Fun Facts About The Spine

A giraffe's neck is built from how many vertebrae, exactly the same number as a human neck?

Seven is the limit for almost every mammal, so the giraffe's neck grew by stretching each bone instead of adding more. Every one of them is over 28 cm long.

Which Greek Titan, condemned to hold up the heavens, names the vertebra that supports the skull?

Atlas bore the weight of the sky, and the topmost vertebra bears the head in the same way. Unlike the bones below, it is a simple ring with no solid body.

Measured standing, at what time of day is a healthy person usually tallest, by a centimetre or more?

Morning wins, because hours of lying down add length that a day spent upright takes away again. In one study, 100 children averaged 1.54 cm shorter by late afternoon.

Which birds can swivel their heads about 270 degrees each way, thanks to fourteen neck vertebrae?

Owls also have extra-wide artery channels in those bones, so twisting the neck that far never cuts off the blood supply to the brain.

What do astronauts gain within a month in orbit, thanks to what weightlessness does to the spine?

Height increases by about 2.5 cm, roughly an inch, once gravity stops pressing the spine and the rest of the skeleton together.

Which shelled animal can never leave its armour, because its spine and ribs are fused into it?

Turtle shells are part of the skeleton, not a mobile home: the upper dome, called the carapace, is fused with the vertebrae and ribs.

The coccyx, the last few bones of the human spine, is named after the Greek word for which bird?

Cuckoo is kokkyx in Greek, and ancient Greek physicians gave the bone that name because its tip resembles the bird's beak when seen from the side.

Which English king's skeleton, found under a Leicester car park, had a spine bent sharply sideways?

Richard III had a curve that left one shoulder higher than the other, yet researchers concluded clothing could have disguised it. DNA from his sister's descendants matched the bones.

Seen from the side, the three natural curves of a healthy spine form the shape of which letter?

S is the shape, and its bends work as shock absorbers. The neck's curve is not there at birth: it forms once a baby can hold up its head.

Christopher Reeve, paralysed when a riding fall broke his top two vertebrae, played which hero?

Superman made Reeve a star in 1978. After the fall at an equestrian event in Virginia he used a wheelchair and a ventilator for the rest of his life.

Which predatory fish have a backbone of cartilage, like the rest of their boneless skeleton?

Sharks get a bargain from the swap: cartilage is flexible and durable yet only about half as dense as bone, so a lighter skeleton saves energy.

Nearly all mammals, even giraffes, share a neck vertebra count; which tree-dweller breaks the rule?

Sloth necks ignore the mammal standard: two-toed species have five or six vertebrae there and three-toed species nine. The only other rule-breaker is the manatee, with six.

Which German dog breed is so prone to spinal disc disease that about a quarter develop it?

Dachshund backs pay for the sausage shape: vets put the problem down partly to an extremely long spinal column paired with a short rib cage.

Which Batman villain wore the hero down, then broke his back, in the comic storyline Knightfall?

Bane first freed Arkham Asylum's most dangerous inmates, leaving his exhausted enemy an easy target. The back-breaking scene was restaged in the film The Dark Knight Rises.

Which hunchbacked bell-ringer did Victor Hugo name after the Sunday the foundling was discovered?

Quasimodo was left at Notre-Dame on the first Sunday after Easter, which carries that name. A real hunchbacked stone carver may have worked at the cathedral while Hugo was writing.

Which Mexican artist painted her damaged spine as a crumbling pillar in The Broken Column?

Frida Kahlo was 18 when a bus accident broke her backbone in three places. She painted the picture in 1944, when doctors had put her in a steel corset.

Which future US president had several spinal operations as a senator and was given the last rites?

John F. Kennedy turned his convalescence to good use, publishing Profiles in Courage, the book that won him a Pulitzer Prize in 1957.

Which therapy based on adjusting the spine did Daniel David Palmer found in Iowa in the 1890s?

Chiropractic grew from the belief of Palmer, a magnetic healer, that manipulating the spine by hand could cure disease. His first patient worked in the same building as his office.

Which neck injury, caused when the head jerks back and forth, is typical of rear-end car crashes?

Whiplash is older than the car: before motoring the same injury was called railway spine, because doctors saw it mostly after train collisions.

Which condition, felt as pain shooting down one leg, shares its name with the body's longest nerve?

Sciatica is caused about nine times in ten by a bulging spinal disc pressing on a nerve root, and most cases clear up by themselves in under six weeks.

Which sideways curve of the spine usually appears between the ages of ten and twenty?

Scoliosis did not slow Usain Bolt, who wrote that it left his right leg half an inch shorter than his left. Girls tend to be affected more severely than boys.

Which region of the spine has the largest vertebrae, built to help carry the body's weight?

Lumbar vertebrae, the five in the lower back, are the largest segments of the whole column, and they lack the rib joints found on the bones higher up.

Which term means an excessive rounding of the thoracic spine, nicknamed dowager's hump in old age?

Kyphosis in its most common form is postural, put down to slouching, and in the young it can be reversed by correcting muscle imbalances.

Which triangular bone, made of five fused vertebrae, sits at the back of the pelvis?

Sacrum is short for the Latin os sacrum, meaning sacred bone, a translation of the Greek name used by the physician Galen. Why he called it that is unclear.

Counting those that fuse at its base, how many vertebrae does a typical human spine contain?

33 is the usual total: 24 separate bones stacked above nine that fuse into two solid blocks at the base. The count at the very tip varies a little between people.

Which British princess chose a wedding dress cut to show the scar from her childhood spinal surgery?

Princess Eugenie had titanium rods fixed either side of her spine at the age of 12, and showed the scar to inspire others living with the same condition.

Which childbirth pain relief is injected just outside the membrane around the spinal cord?

Epidural comes from the Greek for upon plus dura mater, the membrane's name. A thin tube can stay in place throughout, so the medicine keeps flowing for as long as it is needed.

Which automatic response, like jerking a hand off a hot stove, is triggered within the spinal cord?

A reflex takes a shortcut: the incoming signal fires motor nerves inside the cord, and the brain only analyses what happened once the muscles are already moving.

Which bone-thinning disease, common after the menopause, can crush vertebrae and cause a stoop?

Osteoporosis usually gives no warning: there are typically no symptoms until a bone breaks, and the vertebrae are among the bones that most commonly give way.

Which B vitamin, taken before and during pregnancy, can prevent most cases of spina bifida?

Folic acid is the manufactured form of folate, vitamin B9, and more than 80 countries have it added to certain foods, such as flour, to cut the number of cases.

The World Health Organization ranks low back pain as the single leading cause of what worldwide?

Disability from low back pain can begin at any age, childhood included, and the number of cases peaks at 50 to 55 years old, well before old age.

Besides staying active, which habit does the WHO list to help prevent repeat bouts of low back pain?

Not smoking tobacco is on the list along with a healthy body weight, good sleep and a well set-up workplace. Most people get low back pain at least once in their lives.

Which term means loss of movement or feeling in the legs, usually after spinal cord damage?

Paraplegia spares the arms because the damage lies below the neck. An injury in the neck itself can take away movement and feeling in all four limbs.

X-rays of advanced ankylosing spondylitis show a rigid, fused spine named after which plant?

Bamboo spine appears when the outer rings of the discs turn to bone, bridging each vertebra to the next. This form of arthritis typically starts in young adults.

The bundle of nerves fanning out below the spinal cord is named after which animal's tail?

Horse hair is what the trailing nerve roots resemble, so the French anatomist André du Laurens called the bundle the cauda equina, the Latin for that animal's tail.

Spinosaurus, the spine lizard, carried what on its back, held up by rods growing from its vertebrae?

A tall sail of skin most likely joined the spines, which grew to at least 1.65 metres. Ideas for its purpose include display and controlling body temperature.

Spinal nerves C3, C4 and C5, which leave the cord in the neck, join to control which vital muscle?

Diaphragm control belongs to the phrenic nerve, built from those three roots, so a neck broken higher up can leave a person unable to breathe without a ventilator.

Which ancient Greek gives his name to a traction bench once used to stretch injured spines?

Hippocrates is credited with the bench, which used tension to set dislocations and fractures and is a forerunner of modern orthopaedic traction. Whether he designed it himself is uncertain.

Through which opening in the base of the skull does the spinal cord pass into the spine?

Foramen magnum position is a clue for fossil hunters: in species that walk on two legs it sits further forward, so the head balances on top of the spinal column.

A break through both sides of the second neck vertebra is commonly named after which occupation?

Hangman's fracture is a misleading label: one study of judicial hangings found that only a small minority produced it. Falls and road accidents are the usual causes today.