Why Leg Length Discrepancy after THA Matters – and How It Can Be Prevented
One of the keys to a successful total hip arthroplasty (THA) is restoration of appropriate leg length and offset.
Why does this matter? At the 7th Annual ICJR South Hip & Knee Course, Bryan D. Springer, MD, from OrthoCarolina Hip & Knee Center in Charlotte, North Carolina, gave 3 very good reasons:
- Leg length discrepancy is a common cause of patient dissatisfaction after THA. 
- Leg length discrepancy has been found to cause poorer functional outcomes after THA. 
- Leg length discrepancy is the leading cause of litigation after THA. 
What can the surgeon do to prevent leg length discrepancy? Dr. Springer broke it down into preoperative, intraoperative, and postoperative interventions.
The surgeon should identify patients who are at risk for leg length discrepancy, Dr. Springer said, counsel them about the risk and possible outcome, and then document the conversation. Risk factors include:
- Short stature
- Hypermobile female
- Bilateral hip osteoarthritis
- Patients who say their operative leg feels “long”
- Spine/pelvis relationship
- Short femoral neck
The surgeon should also template the hip, preferably electronically, and make it part of the medical record. This shows that thought went into how the leg length will be handled intraoperatively. It also allows the surgeon to refer to the plan during the procedure.
Numerous techniques are available for measuring leg length intraoperatively, each of which has its strengths and weaknesses, Dr. Springer said. The technique the surgeon chooses to measure leg length intraoperatively is not as important as documenting that it was done.
Often, patients’ perception of leg length discrepancy does not correlate with actual leg length, and the discussion about it can be challenging and emotional, Dr. Springer said. The patient may not want to believe the surgeon.
Although it may be difficult, the surgeon should urge patience with the healing process. Moderate leg length discrepancy will usually lessen after a few months as tension on the abductor complex decreases and correction of early pelvic obliquity resolves.
Early physical therapy should be avoided. Dr. Springer shows his patients a simple abductor stretch that helps to correct apparent leg length discrepancy.
Also avoid the temptation to use a shoe lift immediately. Dr. Springer waits at least 6 months before prescribing a shoe lift if the patient is still complaining of leg length discrepancy.
Finally, revision surgery is very rarely needed in leg length discrepancy: It accounts for only about 0.3% of revision procedure, Dr. Springer said.
Click the image above to watch Dr. Springer’s presentation and learn more about leg length discrepancy.
Disclosures: Dr. Springer has no disclosures relevant to this presentation.
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- Clark CR, Huddleston HD, Schoch EP 3rd, Thomas BJ. Leg-length discrepancy after total hip arthroplasty. J Am Acad Orthop Surg. 2006 Jan;14(1):38-45. Erratum in: J Am Acad Orthop Surg. 2006 May;14(5):35A.
- Maloney WJ, Keeney JA. Leg length discrepancy after total hip arthroplasty. J Arthroplasty. 2004 Jun;19(4 Suppl 1):108-10.