What Is Leg Length Discrepancy (LLD)?
If you have a Leg Length Discrepancy, one of your legs is shorter than the other by at least 3mm. (It may be less than that, but the difference must be 3mm to be considered significant.) Leg length difference may just be in appearance, due to pelvis rotation or misalignment. The difference may also be structural, with one of the bones in your leg (or both of them) being truly shorter than the other leg. Making the determination between functional and anatomical will make all the difference in the type of treatment you should receive and your expected results.
Receiving an accurate measurement by a doctor that focuses on this problem can make all the difference in how quickly your body can adapt to the new change and prevent some of the secondary conditions and symptoms associated with a leg length discrepancy. While most people with LLD have no idea they have it, they certainly experience the pain and discomfort that can happen due to an imbalance in the body that commonly affects the spine and extremities.
Upon learning that they have a short leg, patients can be left wondering why this wasn’t diagnosed before and if it’s a rare and unusual condition. This condition is far more common than most people realize, but it’s left undiagnosed because of often inaccurate measurement methods.
Common Signs of Leg Length Imbalance
Could a short leg be causing your pain? You might have a leg length discrepancy if you:
- Always wear out one shoe faster than the other
- Feel like one hip is higher or rotated
- Consistently feel tight on just one side of your back
- Experience SI joint pain, especially after standing
- Can't get your squat or stride to feel symmetrical
- Have chronic lower back pain with no clear cause
How Do I Know If I Have A Short Leg?
There are often no symptoms associated with LLD until you’ve reached 25-35 years of age. Most often, low back pain is what first draws attention to the potential problem (although rarely does the patient believe it’s due to a short leg). While the patient may have experienced chronic lower back pain due to LLD, it’s not uncommon for mid or upper back pain to be present as well.
Another common symptom is pain or injuries that keep occurring on the same side of the body. Repeated injuries to the same-sided hip, knee, ankle is a classic example of an untreated or undiagnosed short leg. Radiating pain (pain that shoots down the leg) but goes away when you lay down may also be present.
Many patients notice a short leg because when they lay on their back with their knees bent, they can see that one knee is higher than the other. Or when they get pants altered, they have to have both sides measured to avoid uneven pant legs or arguments with the tailor about a bad alterations job.
Here are some other things to check:
- Look in the mirror: Does your head tilt to one side? Do your shoulders or collarbones seem uneven? Does one knee cap seem higher than the other?
- Do skirts seem to hang or fall unevenly? Or have you had problems with clothes coming back from alterations uneven?
- Has a massage therapist commented that one side of your body has much tighter muscles than the other? Have you noticed that one of your thighs or legs seems much stronger than the other?
- Has a podiatrist suggested that you should get orthotics, or do you notice that you always wear out one heel of your shoe over the other?
- Do you find that if you have to stand for any length of time, you constantly shift from one leg to the other?
All of these are non-pain related signals that you may have a discrepancy. While we most often wait for pain to be the trigger to take action, you don’t have to wait for that. Like any health problem, the sooner it is detected, evaluated and treated, the easier and faster the recovery.
Does Having A Short Leg Affect Your Neck Too?
In our office, we’ve seen people with a short leg suddenly have their headaches go away once the length differential is corrected. It makes sense that if you think of your feet as the foundation when you walk around, a tilted foundation will have effects all the way up the spine. While a neck problem is usually aggravated based on poor posture, not everyone sits at a computer all day. Neck pain, particularly when your main activity is walking around, may be due to leg length discrepancy.
Which symptoms someone feels with a short leg will vary depending on how different the length is, how active they are, and age. The more active a patient is, the healthier they should get. However, just like having a car with the wheels out of alignment, you may not even notice the problem traveling at slow speeds. Once you’ve had LLD and have maintained an active lifestyle for years, you can start to feel the effects with even a minor leg difference.
The imbalance at the base of your body leads to compensation in weight distribution and spinal curves. The lumbar spine (lower back) can shift laterally over the side of the short leg with curves that compensate for this deviation all the way up the spine. It’s even possible that the jaw (TMJ) can be affected!
Functional vs Structural Leg Length Difference
Functional Short Leg:
Definition: A difference in the alignment of the pelvis and surrounding soft tissue that draws the femur head up and back or forward and away on one side. No significant anatomical measurement difference is found in the lower extremities but symptoms associated with a leg leg discrepancy is noted. Can happen with imbalanced daily activities, trauma, or minor injuries left untreated.
Treatment: Evaluation and treatment via chiropractic adjustments to realign the pelvis. Any heel lift recommendations will be temporary and only to assist in keeping the pelvis in line during the initial phase of adjustments. Additional home recommendations, stretches and strengthening exercises recommended to keep muscle imbalances from pulling the pelvis back out of alignment.
Anatomical Short Leg:
Definition: A difference in the size or length of the upper leg (femur) or lower leg (tibia) usually due to asymmetry in the growth of the leg. Sometimes caused by a fracture, injury, or surgery to one of those bones.
Treatment: We typically do not recommend any action be taken by the patient when the measured difference is less than 3mm. We can add a heel lift inside the shoe for measured differences up to 7mm. Any leg leg discrepancy greater than 7mm is recommended to be treated with a combination of inside the shoe and outside the shoe modifications.
Using a heel lift greater than 7mm can cause changes to ankle biomechanics and should be monitored for patient comfort. Use of heel lifts greater than 7mm can also be challenging, as finding a comfortable shoe that can accommodate the lift without the shoe slipping off can be an issue. Long-term, the short leg should be treated with orthotics with the heel lift built into the custom insert.
Is It Possible To Have Both?
Yes. In fact, most often we do find that the patient’s leg length discrepancy is a combination of functional and anatomical factors. They can be treated simultaneously and usually complement each other in the speed of the patient’s results.
Why Runners, Lifters, and Active Adults Should Pay Attention to Leg Length Imbalances
- Runners: A leg length difference can lead to overuse injuries on one side of the body, IT band tightness, and hip or knee pain. You may notice the problem getting worse the more you run.
- Weightlifters: Imbalances during squats or deadlifts can cause poor load distribution, lower back pain, or even disc injuries. Do you feel like you're fighting to stay straight?
- CrossFit Athletes & Gym-Goers: Without symmetry, performance suffers and injury risk increases -- especially with repetitive movement patterns. You will notice one leg tends to be stronger than the other.
Why Isn’t A Leg Length Difference Found In More People?
Only about 10% of the population regularly seeks chiropractic care, and not all chiropractors look for LLD as a possible factor in achieving the best results. In our office, we have found that of those patients suspected of having a short leg have a measured difference on x-ray of at least 3mm.
LLD may affect 60 – 90% of people, which is why it should be evaluated and considered a factor in patients seeking chiropractic care. Measurement by x-ray is the most accurate measurement method and since we’re looking at millimeters of difference, it is what we recommend.
How Is Leg Length Discrepancy Evaluated & Treated?
In our office, we start with a case history. We will learn more about your symptoms, health history, and daily activities among many things. We are initially looking to determine if your problem can be helped with chiropractic care, but we are also evaluating signs of LLD.
After a physical examination, we will determine if x-rays are necessary. If we end up taking x-rays of the lumbar spine and pelvis, we will take measurements of the height of the femur heads to look for a measured difference. If a leg length difference greater than 3mm is present on x-ray, we will make note that the patient is a good candidate for a leg length discrepancy x-ray.
After several weeks of treatment, we will proceed with a leg length x-ray if warranted. Appropriate heel lifts or orthotics are recommended at that time. If the measured difference is greater than 5mm, the patient will start with a smaller heel lift and gradually increase to the closest possible difference.
Could A Short Leg Be The Cause Your Pain? Let Us Find Out
Let us do an evaluation and find out if you have a leg length discrepancy. Once we know your measurement, we can help you get back to a life free of back pain, sciatica, and hip pain.
Frequently Asked Questions About Leg Length Discrepancy
If your leg length discrepancy is greater than 7mm, you may need to wear “special” or modified shoes. You can still wear most of your regular shoe styles, with a skilled cobbler making modification that are nearly indiscernible to the unsuspecting eye. This can run $50 – $70 per shoe. Some insurance companies will reimburse for this service if deemed medically necessary.
Many patients find just decreasing the leg difference with a heel lift up to 7mm makes a big difference in how they feel and don’t bother to increase their shoes to correct the entire leg length difference. However, if you do decide to modify your shoes, start with just a couple of shoes to see how you feel before investing in more modifications.
Your exercise shoes, your daily work shoes, and possibly a pair of dress shoes are good shoes with which to start. A separate prescription is usually required for each pair of shoes you want to modify. You can also get custom orthotics in our office for $250 that will allow for a heel lift added. This allows for easy transfer from shoe to shoe as needed. A good set of orthotics can last several years and may save you from tons of pain related to leg length discrepancy.
A heel lift typically works well up to 7 mm. When it gets higher than that, the entire shoe should be modified. The patient can still wear a heel lift up to 7mm, with the shoe modification making up the difference. For example, a 12mm difference can be treated with a 7mm heel lift and a 5mm shoe modification.
Since the back of most shoes is often too short to accommodate heel lifts greater than 7mm, the patient may choose to stop wearing the lift if it doesn’t match their lifestyle. Also, heel lifts greater than 7mm may lead to a change in ankle biomechanics and possibly shortening of the Achilles tendon.
Other practitioners will use a tape measure and look to see if you have a difference. This works with major differences, but not when the difference is smaller.
There's also indication that this method is unreliable. That is, one person can get one measurement and another person checking the same patient will get a different measurement. X-rays are the most reliable way of measuring for a leg length difference.
Adjustments work great for functional leg length differences, but won't make your leg grow longer to fix an anatomical difference. We check to see how much of your leg length difference can be adjusted out and how much will need a shoe insert or heel lift.
Absolutely! A long-term imbalance can lead to more wear and tear on one side of the body, but will also cause the pelvis and surrounding muscles to change as well. This imbalance continues to create more pressure on one side of the body until the sciatic nerve becomes inflammed.
.There is leg lengthening surgery that's available, but it's invasive and way more involved and expensive than most people would want to pursue. It's not necessary for smaller leg length differences.