Heel lifts, also known as shoe inserts, are commonly used as

therapy A therapy or medical treatment (often abbreviated tx, Tx, or Tx) is the attempted remediation of a health problem, usually following a medical diagnosis. As a rule, each therapy has indications and contraindications. There are many differe ...

for leg-length differences leading to

knee In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the ...

, hip, and

back pain Back pain is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common ...

. They attempt to reduce stress on the Achilles' tendon during healing, and for various

rehabilitation Rehabilitation or Rehab may refer to: Health * Rehabilitation (neuropsychology), therapy to regain or improve neurocognitive function that has been lost or diminished * Rehabilitation (wildlife), treatment of injured wildlife so they can be retur ...

uses. The intent of a heel lift is not to absorb

shock Shock may refer to: Common uses Collective noun *Shock, a historic commercial term for a group of 60, see English numerals#Special names * Stook, or shock of grain, stacked sheaves Healthcare * Shock (circulatory), circulatory medical emerge ...

or spread pressure on the

foot The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg mad ...

, but to raise one foot in order to shift balance and

gait Gait is the pattern of movement of the limbs of animals, including humans, during locomotion over a solid substrate. Most animals use a variety of gaits, selecting gait based on speed, terrain, the need to maneuver, and energetic efficiency. ...

. As such, these products should be firm and not compressible, in order to add a constant amount of height without causing the heel to rub vertically in the

shoe A shoe is an item of footwear intended to protect and comfort the human foot. They are often worn with a sock. Shoes are also used as an item of decoration and fashion. The design of shoes has varied enormously through time and from cultur ...

. A commonly used formula for calculating the amount lift necessary for short leg syndrome was presented by David Heilig:

L < BU / + C /math>

where 
Duration (D) is 0-10 years = 1 pt

10-30 years = 2 pts

30+ years = 3 pts

SBU is Sacral Base Unleveling (SBU), and L is the amount of Lift required (L). and Compensation (C)> is absent (none) = 0 pts
Sidebending and rotation (of the

spine Spine or spinal may refer to: Science Biology * Vertebral column, also known as the backbone * Dendritic spine, a small membranous protrusion from a neuron's dendrite * Thorns, spines, and prickles, needle-like structures in plants * Spine (zoolo ...

) = 1 pt
Wedging, facet size changes, endplates with horizontal growths, spurring = 2 pts The maximum lift measure within the shoe (i.e., between the

heel The heel is the prominence at the posterior end of the foot. It is based on the projection of one bone, the calcaneus or heel bone, behind the articulation of the bones of the lower leg. Structure To distribute the compressive forces exer ...

and the insole) is ¹/₄ inch, while the maximum lift from the heel to the floor is ¹/₂ inch.Ward RC, ed. Foundations for Osteopathic Medicine. 2nd ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2003.

References

Physical therapy Footwear {{treatment-stub