Labyrinthine artery
A thin artery, usually from the anterior inferior cerebellar artery, that runs through the internal auditory canal to the inner ear. Its occlusion can cause sudden hearing loss with dizziness.
See also: Anterior inferior cerebellar artery
Lack of drive (avolition)
A change in energy, initiative and activity that can appear as reduced or increased drive. Reduced drive is typical of depression, increased drive of mania.
See also: Bipolar disorder, Apathy, Depression
Lacrimal artery
A branch of the ophthalmic artery that runs along the lateral rectus muscle to the lacrimal gland and also supplies the eyelids and conjunctiva.
See also: Ophthalmic artery
Lateral ankle ligament rupture
A tear of one or more outer ligaments of the ankle, usually from rolling the foot inwards. Most cases heal well without surgery using a splint or brace followed by exercise.
Lateral circumflex femoral artery
A branch of the deep femoral artery that runs outward around the femoral neck and supplies the extensor muscles. Its descending branch feeds the widely used ALT flap.
See also: Deep femoral artery, Medial circumflex femoral artery
Lateral meniscus
An almost circular fibrocartilage disc on the outer side of the knee, more mobile than the medial meniscus. It distributes load between the thigh bone and shin bone and absorbs shocks.
Lateral plantar artery
The larger terminal branch of the posterior tibial artery, crossing the sole obliquely and forming the deep plantar arch.
See also: Posterior tibial artery, Deep plantar arch
Lateral thoracic artery
A branch of the axillary artery that runs down the side of the chest and supplies the serratus anterior muscle and the lateral chest region.
See also: Axillary artery
Lead-pipe colon
An X-ray appearance of a rigid, smooth colon without the typical haustra. It develops in long-standing ulcerative colitis through remodelling of the bowel wall.
See also: Ulcerative colitis
Lead poisoning
Poisoning from ingesting lead, for example from old water pipes, paints or ammunition. Typical are abdominal colic, anaemia, nerve damage and developmental disorders in children.
See also: Basophilic stippling
Leech therapy
The use of medicinal leeches, whose saliva contains anticoagulant and anti-inflammatory substances. It is established in plastic surgery for venous congestion in transplanted tissue; for other uses the evidence is weak.
Left colic artery
The first branch of the inferior mesenteric artery, supplying the descending colon and sometimes connected to the middle colic artery via the arc of Riolan.
See also: Inferior mesenteric artery
Left gastric artery
The artery from the coeliac trunk running along the lesser curvature of the stomach, supplying the stomach and lower oesophagus. Its branches are relevant in ulcer bleeding on the lesser curvature.
Leg holding test (Mingazzini)
A test in which the patient lying on the back holds both legs up with hips and knees bent. If one leg sinks, this indicates a mild central weakness.
See also: Barré arm drift test
Legal guardianship proceedings
A court procedure in which a legal guardian is appointed for specific areas of responsibility for an adult who can no longer manage their affairs because of illness or disability.
Lens of the eye
The elastic, clear lens that focuses light onto the retina; clouding of the lens is called cataract.
Lenticulostriate arteries
Thin end arteries from the first part of the middle cerebral artery that penetrate vertically into the basal ganglia and internal capsule. They are a typical site of hypertensive brain haemorrhages and lacunar infarcts.
See also: Middle cerebral artery, Internal capsule
Ligament tear
A tear of a ligament, usually on the outer ankle after rolling it. Most ligament tears heal with a splint and physiotherapy without surgery.
Lightning injury
Injury from a lightning strike with very high but brief electrical exposure. Typical are cardiac arrest, unconsciousness, fern-like skin patterns and eardrum injuries; casualties should be resuscitated immediately.
Lines of Blaschko
Invisible lines of skin development along which some congenital skin diseases appear in streak- or whorl-like patterns. They reflect the migration routes of skin cells in the embryo.
Lingual artery
The artery from the external carotid that supplies the tongue, floor of the mouth and palatine tonsil. In heavy bleeding from tongue tumours it can be deliberately closed.
See also: External carotid artery
Loss of appetite
Lack of desire to eat, for example with infections, depression, cancer or as a side effect of medicines.
Lumbar arteries
Usually four paired arteries from the abdominal aorta that supply the back muscles, abdominal wall and spinal membranes in the lumbar region. They can bleed during spinal surgery.
See also: Aorta
Lyme disease
A bacterial infection transmitted by ticks. A common first sign is a spreading ring-shaped skin redness (erythema migrans); later the joints, nerves or heart can be affected. It is treated with antibiotics.
Large intestine
Last section of the bowel, in which water is extracted from the stool; most gut bacteria live here.
Lateral geniculate nucleus
Lateral geniculate body of the thalamus, an important relay station of the visual pathway between the optic tract and the visual cortex.
See also: Primary visual cortex (striate area)
Leg length discrepancy
Difference in the length of the legs, either anatomical due to bone length or functional due to misalignment. Small differences are common and harmless; larger ones are treated with insoles, shoe raises or surgery.
See also: Pelvic obliquity
Light-headedness
Mild clouding of consciousness with slowed thinking and a feeling of fogginess in the head. Causes range from tiredness and medication to circulatory problems.
Load-related pain
Pain that occurs when a part of the body is under physical load and eases at rest. Examples are joint pain in osteoarthritis or calf pain when walking in circulatory disorders.
See also: Start-up pain