Varus deformity
Encyclopedia
In orthopedics
, a varus deformity is a term for the inward angulation of the distal segment of a bone or joint. The opposite of varus is called valgus
.
The terms varus and valgus always refer to the direction that the distal segment of the joint points.
For example, in a varus deformity of the knee, the distal part of the leg below the knee is deviated inward, resulting in a bowlegged appearance. Conversely, a valgus deformity at the knee results in a knock-kneed appearance, with the distal part of the leg deviated outward.
If this is confusing, just remember that "varus = inward" and "valgus = outward" and always refers to the direction that the distal part of the joint points.
The English-speaking orthopedist's mnemonic is: valgus with a g as in gum means knees that stick together, and varus means a variance or divergence. Another mnemonic is that varus (which sounds like "v-AIR-us") means "more AIR between your legs".
When the terminology refers to a bone rather than a joint, the distal segment of the bone is being described. Thus, a varus deformity of the tibia (i.e. a mid-shaft tibial fracture with varus deformity) refers to the distal segment in a varus alignment compared to the proximal segment.
Varus and Valgus
It gets even more confusing when using the term in relation to the most distal segment in the lower limb (that is not part of the mid foot or forefoot); the calcaneus (heel). The calcaneus is articulated with the fibula, and with the tibia and talus, and thus is part of the ankle and part of the lower leg. Calcaneal varus can be a fixed or flexible deformity. The other terminology is calcaneal inversion. Specifically, calcaneal varus = calcaneal inversion. However, frame of reference is relevant. It is optimal to speak in terms of frames of reference. Example: a posterior view of the frontal plane image of the right heel in weight-bearing positions as measured by an "Acme 2000 foot and ankle goniometer (an arbitrary non-existent piece of equipment)" using their equipment protocol in a biomechanics lab at UNLV Physical Therapy and Athletic Training Gait Lab, was 11 degrees varus/inversion.
To take it further, some use one term when the heel is in contact with the ground, and the other term for a non-weight-bearing context. I choose not to elaborate, and for the sake of ease accept either term as meaning the same in relation to the bones above the calcaneus, as long as all of relevant contextual parameters are communicated.
Calcaneal varus is of course the opposite of calcaneal valgus.
Orthopedics
Orthopedics is the study of the musculoskeletal system. The Greek word 'ortho' means straight or correct and 'pedics' comes from the Greek 'pais' meaning children. For many centuries, orthopedists have been involved in the treatment of crippled children...
, a varus deformity is a term for the inward angulation of the distal segment of a bone or joint. The opposite of varus is called valgus
Valgus deformity
In orthopedics, a valgus deformity is a term for outward angulation of the distal segment of a bone or joint. The opposite deformation, medial deviation of the distal bone, is called varus....
.
The terms varus and valgus always refer to the direction that the distal segment of the joint points.
For example, in a varus deformity of the knee, the distal part of the leg below the knee is deviated inward, resulting in a bowlegged appearance. Conversely, a valgus deformity at the knee results in a knock-kneed appearance, with the distal part of the leg deviated outward.
Terminology
The terminology is made confusing by the etymology of these words.- In Latin, varus actually means "bow legged" and valgus , "knock-kneed".
- Application of these words in adjectival form to other portions of the body by the medical community has resulted in their definitions changing so that they now refer to the angle of the distal segment (i.e. valgus impaction in a Garden I femoral neck fracture).
- It is correct for a knock-kneed deformity to be called both a varus deformity at the hip (coxa vara) and a valgus deformity at the knee (genu valgum); although the common terminology is to simply refer to it as a valgus knee.
If this is confusing, just remember that "varus = inward" and "valgus = outward" and always refers to the direction that the distal part of the joint points.
The English-speaking orthopedist's mnemonic is: valgus with a g as in gum means knees that stick together, and varus means a variance or divergence. Another mnemonic is that varus (which sounds like "v-AIR-us") means "more AIR between your legs".
When the terminology refers to a bone rather than a joint, the distal segment of the bone is being described. Thus, a varus deformity of the tibia (i.e. a mid-shaft tibial fracture with varus deformity) refers to the distal segment in a varus alignment compared to the proximal segment.
Examples
- Hip: coxa varaCoxa varaCoxa vara is a deformity of the hip, whereby the angle between the ball and the shaft of the femur is reduced to less than 120 degrees. This results in the leg being shortened, and therefore a limp occurs. It is commonly caused by injury, such as a fracture...
— the angle between the head and the shaft of the femur is reduced, resulting in a limp. - Knee: genu varum (from Latin genu = knee) — the tibia is turned inward in relation to the femur, resulting in a bowlegged deformity.
- Ankle: talipes equinovarus (from Latin talus = ankle and pes = foot) — inward turning of the heel, resulting in clubfoot with the person walking on the outer part of the foot.
- Toe: hallux varusHallux varusHallux varus is a deformity of the great toe joint where the hallux is deviated medially away from the first metatarsal bone. The hallux usually moves in the transverse plane....
(Latin hallux = big toe) — inward deviation of the big toe away from the second toe. - Elbows: cubitus varusCubitus varusCubitus varus is a common deformity in which the extended forearm is deviated towards midline of the body ....
(Latin cubitus = elbow) — turned inward elbows
Varus and Valgus
It gets even more confusing when using the term in relation to the most distal segment in the lower limb (that is not part of the mid foot or forefoot); the calcaneus (heel). The calcaneus is articulated with the fibula, and with the tibia and talus, and thus is part of the ankle and part of the lower leg. Calcaneal varus can be a fixed or flexible deformity. The other terminology is calcaneal inversion. Specifically, calcaneal varus = calcaneal inversion. However, frame of reference is relevant. It is optimal to speak in terms of frames of reference. Example: a posterior view of the frontal plane image of the right heel in weight-bearing positions as measured by an "Acme 2000 foot and ankle goniometer (an arbitrary non-existent piece of equipment)" using their equipment protocol in a biomechanics lab at UNLV Physical Therapy and Athletic Training Gait Lab, was 11 degrees varus/inversion.
To take it further, some use one term when the heel is in contact with the ground, and the other term for a non-weight-bearing context. I choose not to elaborate, and for the sake of ease accept either term as meaning the same in relation to the bones above the calcaneus, as long as all of relevant contextual parameters are communicated.
Calcaneal varus is of course the opposite of calcaneal valgus.