Is a mild leg length discrepancy, with the right lower limb measuring 13mm shorter than the left, an indication for a simple osteotomy (surgical cutting and realignment of a bone)?

From the Guidelines

Osteotomy is not indicated for a mild leg length discrepancy of 13mm (right leg 783mm vs left leg 796mm) due to the risks associated with the procedure and the availability of effective conservative management options. This small difference (less than 2cm) is generally considered clinically insignificant and usually doesn't require surgical intervention. Conservative management is the preferred approach for discrepancies under 2cm, including shoe lifts or heel inserts in the shorter limb's footwear to equalize leg lengths. These non-surgical options effectively address any potential gait abnormalities or back pain that might result from the discrepancy.

• Key considerations in managing leg length discrepancies include:
  • The size of the discrepancy: smaller discrepancies (less than 2cm) are typically managed conservatively
  • The presence of symptoms: patients with significant symptoms such as pain or gait abnormalities may require more aggressive management
  • The availability of effective non-surgical options: shoe lifts, heel inserts, and physical therapy can effectively manage many cases of leg length discrepancy
• The provided evidence does not directly address the management of mild leg length discrepancies, but it does highlight the importance of non-pharmacological treatments and self-management in patients with musculoskeletal symptoms 1.
• In the context of real-life clinical medicine, it is generally recommended to avoid surgical interventions like osteotomy for minor leg length differences due to the associated risks and the lengthy recovery period involved.

From the Research

Leg Length Discrepancy and Osteotomy

• The given leg length discrepancy is 13 mm (783 mm - 796 mm), which is relatively mild.
• According to 2, the evidence base on the indications for treatment of leg-length discrepancy is poor, and only informal consensus recommendations are available.
• The study 2 suggests that the final extent of a leg-length discrepancy can be estimated with predictive algorithms to within 2 cm, and treatments can include shoe inserts, orthosis, or surgically induced slowing of growth.

Treatment Options for Leg Length Discrepancy

• The study 3 found that shoe lifts can effectively reduce pain and improve function in patients with leg length discrepancy and common painful musculoskeletal conditions.
• However, the quality of the evidence is low, and high-quality research is needed to evaluate the threshold leg length discrepancy to correct and the strategy to do so.
• Osteotomy is mentioned as a treatment option in 2, but it is not specified as the preferred treatment for mild leg length discrepancy.

Biomechanical Effects of Leg Length Discrepancy

• The study 4 found that mild leg length discrepancy can cause compensatory changes during gait, which can affect pelvic motion and lead to musculoskeletal disturbances.
• The study 5 suggests that leg length discrepancies greater than 20 mm can alter biomechanics and loading patterns, resulting in functional limitations and musculoskeletal disorders.

Decision to Treat Leg Length Discrepancy

• According to 2, the decision to treat leg length discrepancy is always elective, and the extent of the discrepancy is not the sole determining factor for the mode of treatment.
• The study 6 emphasizes the importance of careful clinical and radiologic assessment, and repeated analysis of past growth in order to predict future growth and make informed treatment decisions.
• In the case of a 13 mm leg length discrepancy, the decision to treat with osteotomy-simple would depend on individual factors, including the patient's symptoms, functional limitations, and personal preferences, as well as the surgeon's professional judgment 2, 6.