Most of us are familiar with older adults who fall and break a hip — or break a hip and fall. It’s an unfortunate event that adds insult to injury. But young adults are also at risk for hip dislocation from trauma. This time it’s more likely as a result of a high-speed car crash. The incidence of hip dislocations is on the rise, not just from motor vehicle accidents, but also from falls, sports injuries, and getting hit by a moving vehicle if you are a walker.
At first, you might think, Oh, that’s no problem. They can heal easily and quickly and go their merry way. But, in fact, the risk of hip joint arthritis on that side goes way up after a traumatic hip dislocation at a young age. Even more so when there are other injuries along with the dislocation. Bone fractures, torn ligaments, and damaged joint cartilage are often present when the force of the injury is enough to dislocate the hip.
What’s the best way to treat this type of injury with an eye toward future complications like osteoarthritis? In this article, two orthopedic surgeons from the Indiana University School of Medicine discuss what the evidence is for the surgical management of traumatic hip dislocations of this type.
The first thing we learn is that a simple hip dislocation (without a fracture) only results in hip arthritis in one out of every four patients. It’s the dislocations accompanied by a fracture of the joint surface called an acetabular fracture that present later with problems including arthritis. About 88 per cent of those complex fracture-dislocations damage the joint resulting in death of the bone (osteonecrosis) and osteoarthritis.
Can anything be done to prevent these serious complications? The first step is to get the patient to an emergency department or orthopedic surgeon for immediate care. After an examination, X-rays, or other imaging studies, the full extent of the injury may be revealed and the proper care can be given. Damage to the nearby blood vessels, nerves, and soft tissues (such as tendons, ligaments, and muscles) can affect recovery as well.
Anytime the surgeon thinks there might be a loose body (fragment of cartilage, bone, or other soft tissue floating inside the joint), there is reason to do an arthroscopic exam. The surgeon uses an arthroscope to look inside the joint, confirm the diagnosis, and remove the object. CT scans may be done before arthroscopy to show the location and size of any debris in the joint. In fact, studies show that CT should be done because many times loose bodies are present but unseen even with arthroscopic exam.
Dislocations can be (and should be!) reduced. Joint reduction means the surgical team put the hip back in the socket. The goal is to avoid further trauma to the bones and joint. The combination of a dislocated hip and loose body is certainly a recipe for long-term problems. Loss of blood supply to the joint should also be identified and corrected. In the process of reducing the hip, every effort is made to protect the already damaged joint from further stretching injury.
The specific reduction technique used depends on the specific injury. Dislocations can occur forward (anterior), back (posterior), out to the side (lateral), or halfway between (e.g., anterolateral, posterolateral). The technique for putting the joint back in place is specific to the direction of the dislocation. Photos of the maneuver used for reducing a posterior hip dislocation are included. The techniques used for other types of reduction (e.g., Bigelow technique, Allis maneuver, East Baltimore lift) are also described in detail.
The patient must be relaxed (usually asleep under anesthesia) for the reduction to take place. The sooner the better for the best result. Chances of a closed reduction (without making a surgical incision to open the leg) are greater if the attempt is made right after the injury. The longer it takes to get the right kind of emergency medical care, the more time the muscles have to tighten up in pain — and that increases the difficulty of resetting the joint.
When the hip doesn’t go back in easily and/or when there are other injuries present that need attending, then open reduction (surgery with an incision) may be required. Rehab after closed or open reduction is the final step in the management of traumatic hip dislocations. There isn’t a lot of evidence to support one rehab protocol over another. Points of controversy include whether the patient should remain on bedrest or can put weight on the leg, how much, and how soon after surgery.
Sometimes the best management approach is determined by looking at the results patients get using different types of protocols. Right now, based on available results from current studies, it appears that simple dislocations treated quickly with reduction have the best chance of a good-to-excellent result. Anterior dislocations seem to yield the best results. Anyone with multiple problems and/or complications is at risk for delayed recovery with less than excellent outcomes.
And patients aren’t out of the woods if they recover quickly. Reports of osteonecrosis (death of bone from loss of blood) have been reported up to eight years after the initial injury. Osteonecrosis is more common when there is both a hip dislocation and a bone fracture involving the hip socket.
All-in-all, the evaluation and treatment/management of traumatic hip dislocations requires a skilled surgeon who can take charge, identify what’s wrong and the best way to treat it, and get folks into the operating room sooner than later. The authors conclude that much more study is needed to provide surgeons with evidence as to the best approach to take to get the best results in the long-run.