Leg Length Discrepancy Update

LEG LENGTH DISCREPENCY TIPS UPDATE

In our previous newsletter we discussed some of the research around Leg length discrepancy, what causes it and what measures can be taken to help manage it. If you missed our previous newsletter please click here. Today we will take a closer look at how you can get the most benefit from heel lifts (if you have been prescribed one) & what other adjustments you can make. But before we begin, Cameron wanted to share this latest research study!

A new study just published (not yet in print) found a direct correlation between LLD and the severity of scoliosis in adolescents. This Japanese study followed 23 children with significant LLD and observed that in all cases the scoliosis curve (convex side) occurred on the short leg side.

The study concluded the following:
“LLD is a common paediatric condition that can cause scoliosis of the spine. Severe scoliosis may develop if the LLD is ≥30 mm. Long-term studies are needed to examine the effect of LLD resolution on the elimination of scoliosis.”

**TAKE HOME: Have your children checked for leg length discrepancy, especially if there is known scoliosis in the family.


LLD DURING SPORTING ACTIVITIES

Cycling: Those with LLD should also use a raise in the ‘forefoot’ to address asymmetrical pedaling technique.  It is the authors opinion that low back pain and mid-back pain in cyclists can be caused by LLD.  Raises can be secured underneath the cleat, or for recreational cyclists the pedal itself can be altered.

Running:  Those doing a lot of running may consider full sole shoe lifts to reduce asymmetry and back/pelvic malalignment during the various phases of the running action.

Horse Riding: Like cycling, adjustment of stirrup length will help center the rider on the horse and reduce back tension caused by asymmetry.


AUTHORS NOTE

Many athletes and recreational sports people do not associate their sport with back pain as during the activity joint movement and an increase in circulation most often reduces their pain.  When tissues cool down pain may return or worsen in the days following.


IF YOU HAVE BEEN PRESCRIBED A SHOE LIFT - READ THIS SECTION TO GET THE BEST RESULTS!

Although leg length discrepancy (LLD) correction can result in dramatic improvements for some people, for others the changes are slow and progressive. If your symptoms are related to a LLD and you do not experience improvement with a shoe lift correction the following factors should be considered:

Consistency is key! For maximum benefit from your shoe lift it should be worn most of the time you are on your feet. Many clients take their shoes off at home but may still spend a few hours per day on their feet. A slipper with a lift glued to the sole or a thong with an adhesive lift are good options.  It may also be practical to secure the heel lift in place beneath a tight fitting sock rather than wearing slippers or thongs. When changing footwear shoe lifts are often forgotten.  Installing a heel raise in each pair of frequently worn shoes is the best solution.

Older or well-used footwear compromises the beneficial effects of heel raises.  It is common for the inner cushioning and rubber soles of regularly worn shoes to compress (and wear) over time. When LLD is present the effect is magnified on the side which strikes the ground more forcefully (you might remember Usain Bolt in our last newsletter!). Compaction dramatically reduces the effectiveness of a shoe lift.  A good rule of thumb for regularly used walking/running shoes is to replace them every 9-12 months. If you wear a heel raise and are unsure whether your shoes need changing we can easily assess this for you. Give our reception staff a call. We do not charge for this service. In our experience, purchasing new footwear can make a big difference to back pain driven by LLD.

Poor footwear can also compromise LLD correction.  Although comfortable, some shoes have very soft, and spongy soles and inner cushioning.  Implementing a heel lift into these types of shoes is usually ineffective due to the compressibility of the foam or rubber structure.. Sketches are one such brand notorious for this issue. Generally, the firmer the sole and shoe structure, the more effective your heel lift will be.

Purchasing Heel Lifts: The heel lifts prescribed at Warragul Chiropractic have been selected for their ability to resist compression.  Beware of purchasing heel raises which can be easily compressed. They are not an effective solution for leg length correction.

Foot Orthotics do not correct LLD!  There is often confusion as to whether custom orthotics correct LLD.  Orthotics are primarily designed to support collapsed arches. Whilst it is not unusual to find a greater degree of arch collapse (pronation) on one foot when LLD is present, generally most podiatrists will design the orthotic for arch support rather than to also correct LLD. A higher arch support on one side should not be confused with leg length correction at the heel.  We regularly work with podiatrists and advise on building non-compressible heel lifts into custom made orthotics. If you don't have an orthotic specially made to include your heel raise, make sure you always place your heel raise underneath your orthotic.

When LLD exceeds 10-12 mm, wearing a shoe lift can become impractical and somewhat ineffective. Building up the entire sole of the shoe is usually the best option. For a 10 mm leg length difference a combination of a 5 mm sole lift and 5 mm in shoe lift is a good solution. A skilled shoe repairer can resole your shoe.

Compensation for LLD is often lifelong and relearning to walk and weight bear differently can be a challenge, especially in more advanced age groups. As your body adjusts to a shoe lift it may not always be smooth sailing so we strongly encourage regular follow-up visits for treatment, exercises, advice and support.   Remember, your body needs time to adapt to a heel lift.  Whilst some bodies adapt quite quickly, we observe that between 3 and 12 months is a typical readjustment period.


MY BACK PAIN HAS GONE.

CAN I THROW AWAY MY HEEL LIFT?

Whilst your pain may reduce or even disappear with leg length correction, unfortunately you are not cured of LLD.  When a heel raise is removed, or even under-utilized,it is our experience that your previous symptoms will more than likely return. The good news is that less pain means you will be more comfortable exercising and this is one of the best medicine's for your back!  We encourage all clients with LLD to take the opportunity to do your prescribed back strengthening exercises, walking, gym sessions, Pilates, yoga or whatever you prefer to do to maintain your strength and fitness.  Improving your fitness and strength will make your back more resilient to future episodes of pain.

REFERENCES

Knutson GA. Anatomic and functional leg-length inequality: a review and recommendation for clinical decision-making. Part I, anatomic leg-length inequality: prevalence, magnitude, effects and clinical significance. Chiropr Osteopat. 2005;13:11.

Tallroth K, Ylikoski M, Lamminen H, et al. Preoperative leg-length inequality and hip osteoarthrosis: a radiographic study of 100 consecutive arthroplasty patients. Skeletal Radiol. 2005;34:136–139.

Murray KJ, Molyneux T, Le Grande MR, et al. Association of mild leg length discrepancy and degenerative changes in the hip joint and lumbar spine. J Manipulative Physiol Ther. 2017;40:320–329.

Harvey WF, Yang M, Cooke TD, et al. Association of leg-length inequality with knee osteoarthritis: a cohort study. Ann Intern Med. 2010;152:287–295

Campbell TM, Ghaedi BB, Tanjong Ghogomu E, et al. Shoe lifts for leg length discrepancy in adults with common painful musculoskeletal conditions: a systematic review of the literature. Arch Phys Med Rehabil. 2018;99:981.e2–993.e2.