Hip Replacement Dislocation

A Possible Complication of Hip Replacement Surgery

Table of Contents
View All
Table of Contents

Among the most frequently seen complications of hip replacement surgery is dislocation of the hip replacement. Hip replacement dislocations occur in about 4% of first-time surgeries and about 15% of revision hip replacements. This complication is uncommon, but it does occur—sometimes in unforeseen circumstances.

A dislocated hip replacement is considered a medical emergency. If you suspect that your replacement may be dislocated you should seek medical treatment.

This article takes you through the risk factors, symptoms, diagnosis, and treatment options for a hip replacement dislocation, as well as some preventative steps to avoid this complication.

Dislocated hip replacement, X-ray
ZEPHYR / Getty Images

Dislocations of Hip Replacements

Normal hip joints have many surrounding structures that help to stabilize the hip joint. These structures include muscles, ligaments, and the normal bony structure of the hip joint. Together, these structures keep the ball (the femoral head) within the socket (the acetabulum).

When the hip replacement surgery is performed, the hip can become less stable. By losing some of these stabilizing hip structures, the metal and plastic hip replacement can, in some cases, be prone to coming out of joint, or dislocating.

People who have a hip replacement may be instructed to take hip precautions. Hip precautions are various maneuvers a patient who has undergone a hip replacement needs to avoid and are based on the type of surgery they had. These physical activities place the hip joint in a position where the ball could fall out of the socket.

Hip Precautions

Posterior hip precautions include the following:

  • Do not cross your legs.
  • Do not bend your legs up beyond 90 degrees.
  • Do not sit on sofas or in low chairs.
  • Do not sleep on your side.

Most physicians ease these precautions after rehabilitation, but total hip replacements can be less stable than normal hips even years after surgery.

Signs of a Dislocated Hip Replacement

A dislocated hip replacement is painful and you will very likely be unable to bear weight on the affected leg.

If you have engaged in any of the hip precaution behaviors listed above, or have had a fall or other impact injury (such as from a car accident) and your hip is very painful, you should contact your orthopedic surgeon right away or go to an emergency department.

Risk Factors for Dislocated Hip Replacement

Sometimes hip replacements are more prone to dislocation. Factors that can contribute to hip replacement dislocations include:

In some circumstances, patients have no identifiable cause for sustaining a dislocation of their hip replacement.

When to See a Healthcare Provider

A dislocated hip replacement is a medical emergency. People suffering from a hip dislocation will know immediately that something has gone wrong with their implant. Any movement or effort at weight bearing will be painful and difficult.

Medical treatment should be sought as soon as possible.

Diagnosing a Dislocated Hip Replacement

Typical clinical signs of dislocation include:

  • Severe pain
  • Inability to walk or place weight on the affected leg
  • Leg appears shortened
  • Internally or externally rotated hip

People seeking treatment for dislocated hip replacements often describe a snapping sensation, followed by sudden pain.

If a replacement dislocation is suspected, an orthopedist will do a physical exam and order an X-ray to confirm that diagnosis. Sometimes an MRI or a CT scan may be needed.

Treating a Dislocated Hip Replacement

Hip replacement dislocation treatment depends on several factors. The first step is usually to reposition the hip joint.

This procedure, called a reduction of the hip replacement, is performed under anesthesia—either light sedation in the emergency room or general anesthesia in the operating room. During the procedure, your orthopedic surgeon will pull on the leg to reposition the hip within the socket.

Most often the hip "pops" back into position. Pain relief is almost immediate after the hip implants have been repositioned. X-rays will be obtained to ensure the hip is repositioned and to see if there is any identifiable reason for the dislocation.

If multiple dislocations occur, surgery may be necessary to prevent further dislocations. The implants can be repositioned, or special implants can be used to try to prevent dislocations. You will need to discuss with your orthopedic surgeon the cause of your dislocation and what treatments are available for the problem.

New Prevention Approaches

Recent developments in the design of hip replacement implants and the surgical technique of performing a hip replacement may also lower the chance of developing this complication. Implant design can be changed to create a more stable implant.

Implant Design

The most common design changes of implants that help prevent dislocation include:

  • Larger implants: When the ball of the ball-and-socket hip joint is larger, it is less likely to come out of the socket. Some newer implants use a ball that is over 3 centimeters in diameter. The downside of using a larger ball may be some trade-off in the longevity of the implants.
  • More mobile implants: There are implants designed to allow for a broader range of motion of the ball and socket. One of these implants is called a dual mobility cup. These implants allow motion at two separate segments, increasing the mobility needed for the ball to come out of the socket.
  • More constrained implants: Constrained implants are seldom used, but in situations where dislocation is a recurrent problem, they may be helpful. These implants are linked together so that the ball is connected within the socket. The downside of these implants is that the risk of significant failure is increased.

Changes in implant design need to be approached with caution, as there can be problems with newer implants, which may not have a long track record of use in patients. While these implants may lower the chance of dislocation, you'll also want to be sure they don't cause other problems.

There have been some high-profile implant recalls affecting implants that were specifically designed to last longer with less chance of dislocation. Ultimately, these implants were unfortunately shown to be less successful.

Anterior Approach

Anterior approach hip replacement is a surgery performed to minimize the trauma to some of the structures that stabilize the hip joint. Many surgeons feel that the risk of dislocation may be lower after this surgery compared to a traditional posterior hip replacement.

As a result of a lower likelihood of dislocation after anterior hip replacement, often surgeons will recommend against, or provide alternatives to, hip precautions.

Summary

Hip dislocation can be a major complication of total hip replacement surgery and is considered a medical emergency. Fortunately, the chance of dislocation after hip replacement is small, but when it does occur, additional surgical intervention may be required. Minimizing the risk of this complication can be accomplished with certain precautions and the use of specialized implants and surgical techniques.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Dargel J, Oppermann J, Brüggemann GP, Eysel P. Dislocation following total hip replacement. Dtsch Arztebl Int. 2014;111(51-52):884-90. doi:10.3238/arztebl.2014.0884

  2. Jones SA. The prevention and treatment of dislocation following total hip arthroplasty: efforts to date and future strategies. Hip Int. 2015 Jul-Aug;25(4):388-92. doi:10.5301/hipint.5000273

  3. Kunutsor SK, Barrett MC, Beswick AD, et al. Risk factors for dislocation after primary total hip replacement: meta-analysis of 125 studies involving approximately five million hip replacements. Lancet Rheumatol. 2019;1(2):e111-e121. doi:10.1016/s2665-9913(19)30045-1

  4. Medmastery. How to diagnose a prosthetic hip dislocation.

By Jonathan Cluett, MD
Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams.