Knee injuries are common. They include
ligament sprains, torn meniscus, disloca-
tionof the patella, and fracture of any of
the bones in the joint. Chondromalacia
patellaeis common in adolescents.
kneecapSee patella.
knee-joint replacement Surgery to re-
place a diseased knee joint with an
artificial substitute, usually a metal or
plastic implant. Knee-joint replacement
is most commonly carried out in older
people whose knees are severely affected
byosteoarthritisor rheumatoid arthritis.
knock-kneeInward curving of the legs
so that the knees touch, causing the
feet to be kept further apart. Knock-
knee is common in toddlers and may be
part of normal development. In adults
or children, it may be caused by a dis-
ease such as ricketsthat softens the
bones; osteoarthritis or rheumatoid arth-
ritisof the knee; or a leg fracturethat
has not healed correctly. In children, the
condition usually disappears by age 10.
Knock-knee that persists, or is caused
by a disorder, may require osteotomy,
in which the tibia(shin) is cut and re-
aligned to straighten the leg. In adults,
knee-joint replacementmay be needed.
knuckle The name for a finger joint.
koilonychiaA condition in which the
nails are dry, brittle, and thin, eventually
becoming spoon-shaped. It may be
caused by injury to the nail, and may
also be associated with iron-deficiency
anaemiaor lichen planus.
Koplik’s spotsTiny, grey-white spots
that appear in the mouth during the
incubation period of measles.
Korsakoff’s psychosisSee Wernicke–
Korsakoff syndrome.
kraurosis vulvaeSee vulvitis.
kuruA rare, fatal infection of the brain
that affects some inhabitants of New
Guinea. The disease is caused by a “slow”
virus or prion, which has a long incuba-
tion period and is spread by cannibalism.
Symptoms include progressive difficulty
in controlling movements and dementia.
The study of kuru led to the identifica-
tion of prions, which also play a role in
Creutzfeldt–Jakob diseaseand BSE.
kwashiorkorA severe form of malnutri-
tion in young children that occurs
principally in poor rural areas in the
tropics. Affected children have stunted
growth and a puffy appearance due to
oedema. The liver often enlarges, dehy-
drationmay develop, and the child
loses resistance to infection, which may
have fatal consequences. The more
advanced stages are marked by jaundice,
drowsiness, and a fall in body tempera-
ture. Initially, the child is frequently fed
with small amounts of milk, and vita-
min and mineral tablets. A nutritious
diet is then gradually introduced. Most
treated children recover, but those less
than 2 years old may suffer from perma-
nently stunted growth.
kyphoscoliosisA combination of kyph-
osisand scoliosis.
kyphosisExcessive outward curvature of
the spine. Kyphosis usually affects the
spine at the top of the back, resulting in
a hump or pronounced rounding of the
back. The condition may be caused by
any of a variety of spine disorders.In
some cases, a congenitalabnormality
may be the cause. Treatment, which is
rarely successful, is of the underlying
disorder. When combined with a curva-
ture of the spine to one side (scoliosis),
the condition is known as kyphoscoliosis.KNEECAP KYPHOSIS
K
External
ligamentsCruciate
ligamentsFibulaFemurFatMeniscusSynovial fluid
in bursa
Synovial
membraneKNEEPatellaQuadriceps