How To Evaluate For Leg Length Discrepancy

Volume 17 - Issue 6 - June 2004
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Start Page: 68

Continuing Education Course #120 — June 2004

I am very pleased to introduce the latest article, “How To Evaluate For Leg Length Discrepancy,” in our CE series. This series, brought to you by the North American Center For Continuing Medical Education (NACCME), consists of regular CE activities that qualify for one continuing education contact hour (.1 CEU). Readers will not be required to pay a processing fee for this course.

Patients may notice a leg length discrepancy (LLD) but ignore it. Left untreated, discrepancies can lead to further biomechanical problems. In this article, David Levine, DPM, CPed, details how to identify a LLD using various methods and also dicusses how shoe lifts can aid patients.

At the end of this article, you’ll find a nine-question exam. Please mark your responses on the postage-paid postcard and return it to the North American Center For Continuing Medical Education. This course will be posted on Podiatry Today’s Web site (www.podiatrytoday.com) roughly one month after the publication date. I hope this CE series contributes to your clinical skills.

Sincerely,

Jeff A. Hall
Editor-In-Chief
Podiatry Today

INSTRUCTIONS: Physicians may receive one continuing education contact hour (.1 CEU) by reading the article on pg. 69 and successfully answering the questions on pg. 74. Use the postage-paid card provided to submit your answers or log on to www.podiatrytoday.com and respond electronically.
ACCREDITATION: The North American Center For Continuing Medical Education is approved by the Council on Podiatric Medical Education as a sponsor of continuing education in podiatric medicine.
DESIGNATION: This activity is approved for 1 continuing education contact hour or .1 CEU.
DISCLOSURE POLICY: All faculty participating in Continuing Education programs sponsored by The North American Center For Continuing Medical Education are expected to disclose to the audience any real or apparent conflicts of interest related to the content of their presentation.
DISCLOSURE STATEMENTS: Dr. Levine has disclosed that he has no significant financial relationship with any organization that could be perceived as a real or apparent conflict of interest in the context of the subject of his presentation.
GRADING: Answers to the CE exam will be graded by The North American Center For Continuing Medical Education. Within 60 days, you will be advised that you have passed or failed the exam. A score of 70 percent or above will comprise a passing grade. A certificate will be awarded to participants who successfully complete the exam.
TARGET AUDIENCE: Podiatrists.
RELEASE DATE: June 2004.
EXPIRATION DATE: June 30, 2005.
LEARNING OBJECTIVES: At the conclusion of this activity, participants should be able to:
• differentiate among the causes of leg length discrepancy (LLD);
• diagnose LLDs based on observation, gait analysis, X-rays and the use of crepes;
• recognize patient characteristics that can impede the diagnosis of LLDs; and
• prescribe appropriate lifts for patients with a LLD.

Sponsored by the North American Center For Continuing Medical Education.

One can see an obvious LLD in this photo. When these patients stand with their legs together, one leg is forced to bend in order to compensate for the difference in lengths. However, most LLDs are not as obvious.

When patients have an LLD, there are many ways compensation can occur, whether it is through postural changes or development of pathomechanical imbalances anywhere from the back down to the foot.

Even with the largest lifts, trying to save the sole is worthwhile. This provides a more cosmetically appealing result. In order to do this, one may need to stretch the outer sole and add material to fill the areas where it comes up short.

Here one can see a 1/2-inch lift added to an athletic shoe. If it is done properly, it will not only be cosmetically acceptable, but functional. Note that the forefoot of the shoe is beveled to the toe, providing a rocker sole and a lift at the same time.

Here is an excellent example of how not to use a lift. The lift should be separate from the orthotic device. If it is added to the orthotic device, the balance of the orthosis in the sagittal plane will be affected as well as the fit of the shoe for which

A lift can be added to any shoe, even a woman''s dress shoe. Another creative way to add a lift to a shoe like this is to reduce the heel height of the longer side and make no addition to the shorter side. Many people may feel as though a lift will be a c

Author(s):

By David Levine, DPM, CPed

Small, seemingly inconsequential leg length differences (LLD) can lead to symptomatic biomechanical asymmetry. Without careful examination, subtle LLDs can go undetected as can the etiology of the pathology they create. Differences in leg lengths vary from the subtle to the obvious. Once one identifies LLD, practitioners also need to know how to treat it. Understanding the patient’s lifestyle and activity level will help you determine when to address his or her LLD.
Whether it is a difference in appearance of the two feet or a difference in function, asymmetry is often obvious if we know what to look for and why to look for it. For example, a patient may present with hallux limitus. While there are many causes of hallux limitus, if the finding is asymmetric and no trauma was involved in the deformity, then looking for a LLD would be worthwhile.
Another example is assessing the range of motion within each foot. If there are joints that move or feel different between feet, then a LLD may be present. Since the foot is the mobile adapter for the body, it will compensate for the differences more proximally. Asymmetry is often the first clue that the patient has a LLD. Understanding the prevalence of LLD and how these differences can contribute to pathomechanics will yield important clues in helping you provide successful treatment outcomes for your patient’s biomechanical problems.
Addressing the injured joint or chief complaint only without looking at the interrelationship between the injury and the rest of the body can allow some problems to slip by without being properly identified. The injury, ache or pain may improve with the prescribed treatment, but then may resurface if the underlying cause is a LLD that was not properly identified. This may then lead to a pattern of injuries, injuries that may perhaps affect one side of the body from the back down to the foot. The LLD assessment can be an easy addition to your biomechanical exam. Integrating this assessment into your diagnostic work-up will yield beneficial results.

There are many types of LLD such as congenital, developmental and acquired. Congenital leg length discrepancies can have several causes with the most common one being hemihypertrophy. This condition involves one side of the body developing faster than the other. This is an isolated finding most of the time but can, in some instances, affect the kidneys as well. Other causes of LLDs in children include trauma, neurologic conditions and talipes equinovarus. When there is significant LLD in children, leg lengthening procedures (including recent advances in external fixation) are within the realm of possibility for some patients.
When one sees LLD among adult patients, it may be due to leftover differences that were never addressed or identified at a younger age, arthritic processes and surgery such as joint replacement.
LLDs can be a challenge to treat, but even more challenging to identify. The challenging cases are not necessarily those that have a large difference from one side to the other. In these cases, the difference is usually known and of longstanding duration. Fine-tuning may be needed but these patients come in with the awareness and knowledge that a difference exists. The more challenging cases are the adults of any age who come in with a mechanically related chief complaint that needs to be solved.
One of the best ways to determine whether a LLD is present is to ask the patient. Since your patient is the one who has the difference, a little savvy prompting and asking the right questions will give you important clues. Does the patient favor one leg over the other when standing? Does the patient find it generally uncomfortable to stand? Do certain activities such as washing dishes aggravate the condition? If the answers to these questions provide information consistent with an imbalance, then you know where to direct your examination.