A leg length discrepancy (LLD) occurs when one leg is measurably shorter than the other. Even differences as small as 5–10 mm can cause the body to compensate through altered gait mechanics, leading to pain and injury at the foot, ankle, knee, hip, or lumbar spine. LLD is more common than many people realise, and identifying and managing it can provide significant relief from long-standing or unexplained musculoskeletal pain.
Types of Leg Length Discrepancy
Structural (anatomical) LLD – A true physical difference in bone length - either in the femur (thigh bone) or tibia (shin bone). This may be congenital, post-fracture, or post-surgical.
Functional LLD – The bones are the same length, but muscle imbalance, joint stiffness, pelvic tilt, or foot pronation asymmetry creates an apparent leg length difference.
Signs and Symptoms
Uneven pelvis or shoulder height – One hip or shoulder visibly higher than the other.
Chronic low back pain – The lumbar spine compensates for the discrepancy by bending towards the shorter side.
Hip pain – Increased loading on one hip can lead to early-onset arthritis.
Knee pain – Asymmetrical loading can cause knee problems, typically on the longer limb.
Foot and ankle pain – The shorter limb may pronate excessively to compensate, causing foot problems.
Recurrent injuries on one side – Consistently injuring the same leg or side may indicate an underlying LLD.
How We Assess Leg Length Discrepancy
Clinical measurement – Using standardised techniques to measure limb length from the anterior superior iliac spine to the medial malleolus.
Postural assessment – Observing pelvic tilt, spinal deviation, and shoulder asymmetry.
Gait analysis – Identifying compensatory patterns such as hip drop, excessive pronation, or shortened stance phase on one side.
Referral for imaging – Where appropriate, we refer for leg standing X-rays to quantify structural LLD precisely.
Treatment Options
Heel lifts – For structural LLD, a measured heel raise placed in the shoe of the shorter leg compensates for the difference and corrects pelvic alignment.
Custom orthotics – Where foot function is asymmetrical, orthotics address pronation differences and optimise gait symmetry.
Footwear modification – For larger discrepancies (>15 mm), shoe modifications or specialist footwear may be required.
Exercise rehabilitation – Addressing muscle imbalances - particularly hip abductors, core stability, and calf flexibility asymmetry.
Referral – Physiotherapy, orthopaedics, or sports medicine for associated musculoskeletal problems.
Related Treatments at Deal Podiatry
Deal Podiatry in Deal, Kent provides the following treatments for leg length discrepancy:
Book Your Leg Length Assessment at Deal Podiatry
Undiagnosed leg length discrepancy is a common and correctable cause of chronic back, hip, and knee pain. Contact Deal Podiatry in Deal, Kent for an expert assessment and personalised treatment plan.