What is a limb-length discrepancy?
A limb-length discrepancy is when one leg or arm is shorter than the other leg or arm. The difference in length can range from a fraction of an inch to several inches. Some children are born withcongenital limb differences这会导致他们的腿或手臂以不同的速度生长。其他肢体长度差异是由严重的断裂, a fracture that does not heal properly, a bone infection such as骨髓炎, orbone tumors or bone cysts.
Compared to differing arm lengths,leg-length discrepanciesare more likely to affect a child’s daily activities. Legs of two different lengths require children to change their normal posture and walking patterns. Depending on the degree of difference, leg-length disparities can lead to a variety of problems, such as functional脊柱侧弯，臀部，膝盖和脚踝问题。
Children with mild臂长差异often adapt well to the difference. However, a difference in arm length of two to three inches or more can interfere with activities of daily life and should be addressed.
肢体长度差异的类型
- 结构差异 - 一条腿或手臂的骨头比另一个肢体中的骨头短。
- Functional discrepancy – bone lengths are equal in both legs or arms, but a joint contracture (low joint mobility) in a knee, hip, shoulder, elbow, or other joint throws off the symmetry in the limbs.
What are the symptoms of a limb-length discrepancy?
The symptoms of a limb-length discrepancy vary widely from child to child based on whether a leg or arm is affected, the degree of difference in length, and the cause of the condition.
一些常见症状包括：
- one leg or arm is shorter than the other (this is not always obvious)
Signs of leg-length discrepancy
- problems with posture, such as a tilting shoulder
- 步行问题，例如林或脚趾行走
- a knee that's chronically hyperextended on the short side and flexed on the long side
- 背部，臀部，膝盖或脚踝疼痛
手臂长度差异的其他迹象
- 难以在骑自行车上到达两个车把
- 难以用双手握住汽车的方向盘
- 难以坐在椅子上坐在椅子上站立
是什么导致肢体长度差异？
Congenital (present at birth) limb-length discrepancies develop during pregnancy. Others are caused by illness or trauma.
先天性肢体长度差异
- Some children are born with limb-length discrepancies when one or more of the long bones in a leg or arm do not develop fully during pregnancy. In most cases, there is no known cause for this.
- Some leg-length discrepancies occur when a child is born with a problem that changes the alignment of their hips, such as coxa vara or developmental dislocation of the hip.
受伤或与疾病有关的肢体长度差异
- 复杂的骨折或无法正确愈合的骨折可以减慢受影响的骨骼的生长。在愈合过程中，一些骨折也会导致骨骼过度生长。这在大腿（股骨）受伤中最常见。
- Damage to the growth plate through injury or a bone infection such as osteomyelitis can affect growth. Growth plates are soft areas at each end of the long bones in the arms and legs where bone growth takes place. When a teen or young adult reaches adult height, the growth plates harden into solid bone. If the growth plate in one limb is damaged, the other limb will continue to grow and a difference in length will develop over time.
- Bone tumors and bone cysts can block bone growth. Depending on the location and size of the tumor or cyst, removal through surgery,radiation, or化学疗法可能导致骨骼生长更慢或完全停止生长。
- 脑瘫and other neuromuscular problems can cause problems with a child’s alignment and overall posture, possibly leading to a limb-length discrepancy.
我们如何照顾肢体长度差异
TheLimb-Lengthening and Reconstruction Program在波士欧宝彩票平台顿，儿童医院为患有腿或手臂差异的儿童和年轻人提供综合护理，这些儿童和胳膊或手臂差异在出生时或受伤或疾病引起。我们的团队，借鉴了我们两者的专家下肢计划andHand and Orthopedic Upper Extremity Program，在非手术护理和肢体延长和重建程序方面具有深厚的专业知识。
Our clinicians have treated thousands of babies, children, and young adults with conditions that range from routine to highly complex limb differences. We also offer the benefits of the extensive services available at Boston Children’s, as well as some of the most advanced clinical and scientific research in the world.
我们将与您和您的孩子一起审查可用的选择，并根据孩子的个人需求来确定最佳的治疗方法。
肢体长度差异|Diagnosis & Treatments
How is a limb-length discrepancy diagnosed?
诊断肢体长度差异的第一步是骨科医生的完整病史和身体检查。在考试期间，医生将测量孩子的肢体，以计算他们的长度不同。
If your child has a leg-length discrepancy, the doctor may watch your child walk to look for signs that they are compensating for their different leg lengths. Their doctor may also ask your child to stand with a block under their shorter leg to measure the amount of correction needed to bring their hips and the rest of their body into alignment.
您孩子的医生也可能会订购x-rayor other imaging tests for a more precise measurement of the discrepancy.
How are limb-length discrepancies treated?
Limb-length discrepancies can be treated in several different ways. Some treatments involve surgery while others don’t. Your child’s orthopedic surgeon will talk with you about the options for your child based on:
- your child's age, overall health, and medical history
- 四肢受影响（腿或手臂）
- the amount of discrepancy
- your child's tolerance for specific medications, procedures, or therapies
- 您和您的孩子的期望和偏好
Some treatments to equalize limb length are simple and safe. Others, especiallylimb-lengthening surgery,是复杂的,有患并发症的风险。
Non-surgical treatments for leg-length discrepancy
几种非手术治疗可能有助于提高功能，尤其是如果您的孩子的长度差异轻度（腿不到一英寸；手臂小于两英寸）。
- Ashoe lift在孩子短腿的鞋子内，可以平整腿部长度的差异。鞋子升降机可以帮助您的孩子走路和跑步更轻松，减轻背部疼痛。
- Physical therapyincludes special stretches and exercises that can help reduce pain and increase overall function.
- Occupational therapyfocuses on developing your child’s fine motor skills, such as handwriting.
- 自适应设备can help your child with everyday activities, such as tying their shoes, buttoning their shirt, and holding a book.
- 假肢可以设计成适合短的肢体。它们还可以替换已截肢的肢体的全部或部分。
肢体长度差异的手术治疗
Leg-shortening surgery
如果您的孩子的腿长差异预计将在您的孩子达到成人身高时（两到六厘米之间），则他们的外科医生可能建议缩短更长的腿。缩短程序缓慢增长较长的腿，因此较短的腿可以追赶。通常，这比肢体延长手术更安全，并导致并发症更少。您的孩子在成人身高会比如果没有腿部差的手术要短。
- Epiphysiodesis在孩子上执行尚未完成生长ing. The surgeon fuses the growth plate, either temporarily or permanently, to prevent growth in the longer limb. Timing is important in order to avoid over- or under-correction of the leg’s length.
- Epiphyseal staplinguses staples that are surgically inserted on each side of the growth plate. Once the legs are of equal length, the staples are removed.
- Bone resectioninvolves removing a section of bone in the longer leg. This can be performed on adults or adolescents who have reached their adult height.
Limb-lengthening surgery
Limb-lengthening surgery stimulates new bone growth in the shorter leg or arm. Limb lengthening is performed only on patients with significant limb-length discrepancies that interfere with activities of daily life. It is typically performed when patients are in their late teens or early adulthood.
Lengthening surgeries take several months and may need to be repeated, depending on your child’s stage of growth and the extent of their limb-length difference.
- 在肢体延长的第一阶段，骨科外科医生切断了要延长的骨头（一种称为截骨切开术的过程）。然后，他们连接一个延长的设备，您的孩子将佩戴几个月。下面更详细地描述了延长设备的类型。
- 在接下来的几个月中，您或您的孩子每天都会调整设备，以增加骨头两端之间的间隙。这将刺激人体的自然愈合过程，以创建新的骨头以填补空间。
- While the lengthening is taking place, your child will need to have regular visits with their orthopedic surgeon to ensure the lengthening is going smoothly and address any possible complications before they become serious.
Types of limb-lengthening devices
There are two types of limb-lengthening devices. One type is worn on the outside of the arm or leg. The other is an internal device that is more precise and reduces the risk of complications and infection.
External fixatorsare worn on the outside of the limb and are attached to the bone by pins. The patient or family adjusts the device daily to increase the distance between the two ends of bone. Once the correct length is reached, the device remains on the leg or arm while the new bone hardens and becomes strong. The device is then surgically removed.
Theinternal fixator (PRECICE Nail)is a nail that is surgically inserted inside the bone after the osteotomy. Using an external magnet that causes the nail to expand, the patient or family slowly lengthens the bone a tiny amount each day until the desired length is reached. Like the external fixator, the internal fixator is removed once the limb has been lengthened and new bone has formed.
Left humerus: A. prior to lengthening; B. one year after initial lengthening of ~4.5 cm using a PRECICE nail; C. immediately after second lengthening of ~4.5 cm; D. six months after second lengthening.