Imagine walking with a leg length discrepancy of an inch or more—how would it affect walking, running, and getting around. Now imagine being a child. You walk with a limp. Maybe your spine is curved. Your back hurts, and you’re tired all the time. Other kids might tease you.
Leg length discrepancies, where one leg is noticeably shorter than the other, can happen in children and adults. It can be congenital or caused by illness or injury. In any case, it is at least annoying and can be associated with more severe conditions.
In Part 1 of the leg length discrepancy series, we’ll give you an overview of the condition. Later, in Part 2, we’ll talk about how it is treated.
What is Limb Length Discrepancy?
Limb length discrepancy is a condition in which either the two arms or the two legs are of noticeably different lengths. Many people have arms or legs of different lengths, but the difference is so small that they may not even know there’s a difference at all.
But for those who have a significant limb length discrepancy, there can be functional difficulties and mild to severe medical problems to overcome.
Arm Length Discrepancy
The bones of the arms have two growth plates—one at the shoulder and the other at the elbow. Bone growth occurs around these plates, which become solid bone when a child has reached skeletal maturity. However, sometimes one arm is prevented from growing normally, and it remains shorter than the other.
While it may cause fewer problems than a leg length discrepancy, an arm length discrepancy of two or more inches can become an interference. For example, it can be more difficult to securely hold bicycle handlebars or car steering wheels. In addition, playing a musical instrument may be more of a challenge.
Leg Length Discrepancy
A leg length discrepancy is more problematic. Among other things, leg length can affect one’s ability to walk and move about efficiently, as well as their spinal alignment. Therefore, a length discrepancy of more than one-half inch will need some kind of intervention, from adding lifts to shoes to complicated lengthening procedures.
A leg length discrepancy affects posture and ability to perform daily activities. In addition, significant differences may lead to diseases and ailments such as arthritis, scoliosis, stress fractures, and knee problems.
What are the Two Types of Limb Length Discrepancy?
There are two ways to describe the types of limb length discrepancy—anatomical vs. functional and congenital vs. illness or injury-related.
Anatomical vs. Functional
An anatomical or structural discrepancy means that one leg is physically shorter than the other. A functional discrepancy is due to problems with soft tissues, joints, or ligaments.
Congenital vs. Illness or Injury
A child with a congenital leg length discrepancy develops the condition in the womb and is born with limbs of different lengths. The other type comes from the effects of bone diseases or bodily trauma.
Causes of Leg Length Discrepancy
Congenital (Idiopathic) Leg Length Discrepancy
It is unknown why some babies are born with leg length discrepancy, where one leg never fully developed. For some, the hip alignment is off, or the hip is dislocated. The condition usually becomes noticeable when the baby begins crawling and walking. Clubfoot, hip dysplasia, and other congenital conditions may contribute to the discrepancy.
Leg Length Discrepancy and Bone Defects, Diseases, and Tumors
Bone diseases affecting leg length include Ollier disease, cancer, neurofibromatosis, joint inflammation, and infections. Conditions such as cerebral palsy, paralysis, and spasticity are also contributors.
Any type of bone tumor or its treatment can affect bone growth on one side. For example, osteochondroma may damage growth plates, osteosarcoma affects growth plates and leg bones, and fibrous dysplasia weakens bones. Wilms’ tumor causes hypertrophy on one side, making one leg shorter. Enchondroma grows inside the bone marrow and affects growth.
Leg Length Discrepancy and Broken Leg Bone
Sometimes, a broken leg does not heal properly. A complicated break can lead to a leg length discrepancy. It may happen if:
- The leg was broken in several places.
- Connecting tissues was severely damaged.
- It was an open fracture.
- A growth plate was damaged.
Leg Length Discrepancy and Knee Osteoarthritis
Studies have linked leg length discrepancy to osteoarthritis of the hip or knee. One knee “ages” faster than the other when, many say, there is a difference of 20 millimeters or more. Others claim even 5 millimeters can make a significant difference.
Leg Length Discrepancy and Scoliosis
Scoliosis is both a potential cause and outcome of leg length discrepancy. Scoliosis patients often have uneven legs as a major symptom. The discrepancy can bring about scoliosis in some people when the body attempts to compensate for the difference.
Leg Length Discrepancy after Hip Replacement
It may be difficult to restore a patient’s equal leg length after hip replacement surgery. Arthritis, often the reason for hip replacement, can cause bone loss and leg shortening. Also, to ensure a stable new hip joint, stretching the surrounding soft tissues may be necessary, creating a slightly longer leg.
How is Limb Length Discrepancy Diagnosed?
Diagnosis begins with a medical history of family background and any injuries and illnesses. Next, the doctor observes the patient’s posture and movement. Tests may include X-rays, CT, and MRI. Radiography provides an image of the entire leg, and measurements involve a simple tape measure and manual palpitations. A doctor may place wooden blocks below the shorter leg to measure the extent of the difference.
We’re Looking Forward to Helping You at Our Chiropractic Offices in New Jersey!
At the Bergen Chiropractic and Sports Rehabilitation Center, our chiropractic team, led by Dr. Gregory Doerr, follows the highest and most professional medical standards to provide superior chiropractic help. After all, our mission is to provide unparalleled patient care and services in a comfortable healing atmosphere. Contact us to learn more about our chiropractic services! Our chiropractic offices in Cliffside Park, Hackensack, and Fairfield, New Jersey, are ready to welcome you. Also, feel free to access our blog page for more information on chiropractic treatments!