Limb length discrepancy, or LLD, isn’t as rare as some people think. In fact, up to 90% of the general population has it.
On average, people have a difference of just over five millimeters of LLD, which can then cause poor weight distribution.
However, in some cases, limb length discrepancy can be a significant problem that may affect a person’s overall health.
What Is Limb Length Discrepancy?
Limb length discrepancy is loosely described as a difference between lengths in the right and left leg.
In most cases, it’s a very unnoticeable difference. In others, though, it can be challenging to live with.
Also known as LLD, this discrepancy can develop as a person ages and get worse without treatment.
What Causes Limb Length Discrepancy?
Most humans are born with limb length discrepancy, and it’s highly likely to be unnoticeable.
Still, in more severe cases, it can occur due to infection, trauma, and disease.
A few of the most common causes of LLD include:
Bone infections that happen during an individual’s early childhood may cause limb length discrepancy, resulting in poor bone development.
Previous Leg Bone Injury
Broken leg bones can cause limb length discrepancy if allowed to heal in a shortened position than pre-break.
This issue is most likely to occur if the bone breaks into several pieces or if the muscle tissue was exposed. For example, open fractures can be a common cause of LLD.
There’s an even higher chance of LLD if the bone break occurs during a person’s younger years.
As children’s bones grow faster, it can cause the bone to be longer than the other non-broken side.
Alternatively, the bone can also grow back slower than expected, causing shortness.
Also known as dysplasias, bone diseases can also cause LLD, the most common being:
- Ollier disease
- Multiple hereditary exostoses
Other Common Causes
- Juvenile arthritis
- Neurological conditions
- Joint inflammation during growth
- Idiopathic (unknown) causes
What Is the ICD 10 Code for Limb Length Discrepancy?
ICD codes can provide vital information for patients about their medical charts, bills, hospital records, and more.
Using these codes, doctors can ensure patients get the appropriate treatment and charges for received care.
Limb length discrepancy has an ICD 10 code of M21.70 under the Rheumatology specialty.
How Common Is Limb Length Discrepancy?
As mentioned, limb length discrepancy is widespread among adult and pediatric populations. Up to 90% of the general population has some inequality in their limbs.
With that said, the average discrepancy is typically one or fewer centimeters and is often undetectable.
The Growth Study Center of Children’s Hospital in Boston found that out of 376 patients, 95.5% had significant LLD.
It’s often considered a normal finding; however, it’s not optimal for musculoskeletal development and function.
How Do I Know if I Have Limb Length Discrepancy?
Limb length discrepancy can present itself in many ways outside of being visible to the human eye.
Several of the most common symptoms and findings include:
- Lower back pain
- Sciatica pain
- Disc herniation
- Hip and knee pain
- Degenerative knee disorders
- Altered gait patterns
How To Measure Limb Length Discrepancy
Tape measures are most commonly used in clinical settings to measure limb length discrepancy.
Doctors will measure between the anterior superior iliac spine and the medial malleolus. It’s best to consider the length from the pelvis to the heel’s bottom for measuring at home.
It’s important to record both the right and left legs’ length to determine if there’s a significant difference.
Some clinicians also prefer to measure from the medial malleoli of the ankle to the umbilicus.
Limb Length Discrepancy Treatment
As with any other ailment, the treatment for limb length discrepancy differs based on severity.
Specific treatments could also be recommended for children versus adults and vice versa.
Common Treatments for Children
As long as the LLD isn’t significant, the majority of treatment options for children are non-surgical.
With the help of an orthopedic surgeon, a treatment plan can be developed by considering:
- The size of the discrepancy
- The parents’ expectations
- Child’s tolerance for specific therapies
- The age of the patient and medical history
The most common non-surgical treatments for children include:
- Shoe Lifts
Shoe lifts are a type of orthotic that is to be placed inside the shoe to assist with back pain.
They add height to one leg so that walking can be done quickly and, therefore, assist with realignment.
More severe LLD cases can be assigned prosthetics, especially when patients won’t benefit from surgery.
With prosthetics, they will be custom-fit to the patient’s size and can be worn to accommodate length differences.
Some of the common surgical treatments for children and adults include:
- Leg-Shortening Surgery
There are three different types of leg-shortening surgeries for patients.
Most surgical options are reserved for LLD cases that are between two and six centimeters by the time the patient’s mature.
Leg-shortening surgeries are often seen as the “safer” option because they have fewer complications.
The three types of surgeries include:
Using this procedure, surgeons can slow the rate of growth in the longer leg.
2. Epiphyseal stapling
Another option for slowing growth is epiphyseal stapling, which requires the insertion of surgical staples on the growth plate.
3. Bone Resection
By removing a small bone section in the longer leg, both limbs will become equal in size.
- Leg-Lengthening Surgery
On the other hand, leg-lengthening procedures are only used for LLD cases with more than four centimeters of difference.
These surgeries can take several months to be fully completed, and they include:
1. External fixation
Using an external fixator, two surgically separated bones will be attached by pins, allowing for gradual adjustments for lengthening.
2. Internal fixation (PRECICE Nail)
This procedure requires the surgeon to cut the shorter leg bone in two and then placing a motorized magnetic nail in the bone. Doing this allows for slow lengthening.
Does Limb Length Discrepancy Have To Be Treated?
More often than not, if the difference in length is insignificant, treatment isn’t necessary.
Unless the individual begins to experience significant symptoms and signs of discomfort, treatment isn’t required.
On the other hand, with regular doctor’s appointments, most cases of limb length discrepancy can be treated early on.
If treatment is required, there are plenty of surgical and non-surgical options available.
The majority of treatments are safe and effective, requiring minimal danger to the patient.
Depending on the individual’s health, an orthopedic surgeon can provide an accurate treatment plan for long-term viability.
What Are Signs My Limb Length Discrepancy Is a Problem?
Unlike other disorders and diseases that get worse silently, knowing when to seek help with LLD is simple.
Often, general discomfort in the hip, pelvis, and lower back regions could suggest that medical intervention is required.
Also, if children are noted to have significant differences in leg length, treatments could be required.
Plantar fasciitis is another early sign of LLD, especially in patients with LLD between one and two centimeters.
Getting medical assistance is essential for a select few, mainly because it can lead to significant health problems.
Osteoarthritis is one of the most common symptoms of limb length discrepancy, which is more commonly found in the knees.
Adding an excessive load to one knee prevents healthy weight distribution and more wear and tear on the joints.
To prevent the likelihood of osteoarthritis, both limbs should be at equal or near-equal length with functional symmetry.
Limb Length Discrepancy Products
The Original EVENup Shoe Balancer helps the body to experience even weight distribution.
After wearing the balancer, the wearer will begin to experience reduced body strain and added length.
It’s designed to fit over the base of shoes using rubber hook and loop straps to hold it in place.
With a non-skid rubber outsole, there are two layers of added protection to ward off slips and falls.
They are specifically designed to even the legs’ length from the sole to the hip to aid with walking.
The product has also been tested by two podiatrists and has won the 2013 Merit Award and Top 10 Innovation Award.
Depending on the wearer’s needs, there are two thicknesses to choose from: half an inch and one inch. Also, each lift comes in sizing from small to extra large.
The Procare ShoeLift Shoe Balancer has a similar design to the Original EVENup Shoe Balancer.
Wearers will have an extra inch of lift to help balance LLD and reduce body strain. The bottom of the shoes features a special rubber sole for anti-skid properties.
The unique design of the leveler allows the wearer to use it on either the left or right foot. Also, it’s easy to put on, as it can be adjusted using the user-friendly strapping.
To help with heel pain, I highly recommend the Premium Adjustable Orthopedic Heel Lift.
In each pack, two lifts can help fight leg length discrepancies, injuries, heel pain, and more. The lifts are made from high-quality rubber to ensure there’s plenty of healthy foot support.
Fortunately, these lifts can be put inside sports shoes, dress shoes, and work shoes for all-day comfort. There are three different adjustments at ⅛-inch each for more precise support.
Another option for adjustable heel lifts is the Dr. Foot’s Adjustable Orthopedic Heel Lift Inserts.
There are two- and three-layer designs available, depending on the level of required adjustability.
Wearers can add or remove layers at home using a strong self-adhesive. Once the adhesive wears down, the lifts can be washed, air dried, and reapplied.
The high-quality medical-grade PU gel is incredibly soft and durable for years of wear. Also, it features moisture-wicking and complete washability.
The innovative design of these lifts makes them comfortable to wear without crowding shoes. They also fit inside all shoes, including work shoes, dress shoes, and casual sneakers.