Avascular Necrosis FAQ’s

What is avascular necrosis?

Avascular necrosis describes a process through which bony tissue dies due to not receiving an adequate blood supply. This can occur anywhere in the body, however, there are certain locations that are known to be more prone to develop avascular necrosis – for example, femoral head, talus and scaphoid.

What causes avascular necrosis?

There are a number of different potential causes of avascular necrosis: it has been shown to be associated with the use of certain drugs (e.g. prednisone), it can occur as a result of trauma, be associated with other medical conditions such as antiphospholipid syndrome or protein C or S deficiency, has been linked to excessive smoking, is associated with certain chemotherapy drugs and has even been shown to be associated with deep sea divers who experience “the bends”

However, there are a good number of cases of avascular necrosis that occur without an obvious identifiable cause.  We refer to these cases as “idiopathic”.

How long does it take for avascular necrosis to develop?

The period of time that it takes to develop avascular necrosis will largely depend on the cause.  For example, for drugs such as prednisone or chemotherapy drugs to be present in sufficient quantities in a person’s bloodstream to be able to cause avascular necrosis, they need to be taking such drug for an extended period of time (usually over a number of months). 

However, if the cause is related to physical trauma then avascular necrosis can be detected as early as four to six weeks after the injury (e.g. talar avascular necrosis, where “Hawkins sign” can be used as a radiographic marker of the development of avascular necrosis in this area). 

Can you reverse avascular necrosis?

While the process of avascular necrosis is not reversable per se, it is possible to undergo treatment to prevent the progression of avascular necrosis from its early stages to full-blown tissue death and as such preserve some function in the joint that is affected.  Traditionally, early stages of avascular necrosis of the femoral head are thought to have benefited from a procedure known as a core decompression, which essentially involves drilling into the avascular necrotic lesion to allow blood to reach the area and to prevent worsening of the hypoperfusion of the areas of the femoral head undergoing avascular changes.

There are other areas of the body that do benefit from treatments of a similar type, for example in the talus retrograde drilling of an avascular necrotic lesion is a widely recognized treatment option with varying degrees of success.

How to diagnose avascular necrosis?

For many people the first sign that they may be suffering from avascular necrosis will be development of pain in or around the affected area.  For patients with avascular necrosis of the femoral head this will present as hip pain, for patients with avascular necrosis of the talus this will present as ankle or foot pain and broadly speaking whichever area of the body has undergone avascular necrosis will begin to become quite sore and painful, particularly with movement or weight-bearing.

It is important to seek medical attention for any pain of this type, as avascular necrosis can show up on plain film x-rays even in its early stages.  However, even if it does not, there are other ways to be able to diagnose the early stages of avascular necrosis that have not yet shown signs of developing on a plain film x-ray.  CT scans and, more commonly, MRI scans are used to give your physician more information regarding the bone itself as well as the overlying cartilage in bones that form joints and the fluid content of the bone which may indicate an abnormal process. 

For patients with any type of persistent and refractory joint pain, consultation with a specialist orthopedic surgeon early on is beneficial in assessing avascular necrosis as it allows us to both diagnose the condition and establish, if any, the cause.

How to treat avascular necrosis?

As previously mentioned, there are a number of surgical procedures that have been shown to yield some benefit in patients who have developed avascular necrosis in a bone, particularly in bones that form joints.  However, while treating the patient surgically is often the best option, it is also important to try (wherever possible) to establish a clear cause of the avascular necrosis.  If this is possible, cessation of the offending drug or treatment plays just as important a role in the treatment of the patient as does any possible surgical procedure that they may have to undergo. 

This presents challenges, as patients are often taking these medications in relation to other medical conditions, and it may be unfavorable to stop taking these medications with due consideration to the condition that they are treating.  At this point in time it becomes important to discuss with your orthopedic surgeon as well as your treating physician for any other medical condition the development of avascular necrosis and the consequences of both continuing to take the medication as well as the consequences of stopping the medication and any possible alternatives to the medication that your physician may be able to offer you.

Unfortunately, in cases where avascular necrosis has reached its advanced stages, it may not be possible to halt the progression of avascular necrosis further, or it may have caused destruction of the bone anatomy to such a point that more invasive surgery may be necessary.  These surgical procedures can include osteochondral allograft, resections, arthroplasty and possibly even fusion.  

Can you die from avascular necrosis?

The development of avascular necrosis in and of itself will not pose a threat to a patient’s life.  Although it is death of bony tissue, it is most commonly bony tissue alone that is affected by his phenomenon.  All of the basic human functions will go unaffected by this condition and as such this is not an emergency and there is no immediate threat to life.  It does pose a risk, however, of decreasing the patient’s quality of life to a point that may exacerbate certain other conditions. 

For example, in avascular necrosis of the hip, if left untreated and undetected, patients may experience severe and debilitating hip pain that they are unable to exercise with or even comfortably ambulate with, and this may cause the patient to choose to become more sedentary.  This sedentary lifestyle is often detrimental to cardiovascular health and in patients with diabetes it can significantly change the dynamics of their blood sugar control. 

Can stem cell research cure avascular necrosis?

While significant and important developments are being made in the area of stem cell research, to date there have been no high quality studies that have demonstrated the ability of stem cells to regrow deficient bony anatomy as a result of avascular necrosis.  At this point in time we simply cannot recommend stem cell therapy for avascular necrosis as it is not known if this type of therapy holds any benefits for avascular necrosis patients. 

Is arthritis the same as avascular necrosis?

Although avascular necrosis around the joint can ultimately lead to the development of arthritis, not everybody who suffers from avascular necrosis will go on to develop arthritis necessarily. The term arthritis simply refers to inflammation within a joint and can happen for a great number of reasons, one of which is recognized to be avascular necrosis.

However, avascular necrosis itself is the death of bone tissue related to poor blood supply, and although if left untreated and undiagnosed it can lead to arthritis in its later stages, there are a great number of patients who present to medical professionals in early stages of avascular necrosis and are able to be successfully treated so that they do not go on to develop arthritis as a result of this condition.

Will avascular necrosis spread?

The possibility of suffering from avascular necrosis in multiple different parts of the body will entirely depend on the cause of avascular necrosis. For patients who suffer from this phenomenon due to a traumatic injury, the development is unrelated to any systemic issue and as such will be isolated to the area which was initially injured.

However, if the cause is systemic (e.g. related to chemotherapy or corticosteroid use) then the possibility does exist that a patient will undergo avascular necrosis in different parts of the body. This is, however, exceedingly rare and it is most commonly only one area of the body that tends to be affected by avascular necrosis even from systemic causes.

That being said, once avascular necrosis is diagnosed in one area of the body, it is important to continually monitor other areas of the body for pain so that, if avascular necrosis develops elsewhere, it can be caught and treated early in order to minimize risk of requiring invasive surgery.

What is laminectomy and what is the purpose?

Laminectomy involves removal of the back of the vertebrae so as to remove pressure from the spinal cord or the spinal nerves in the vertebral column. This can be performed in the neck, chest, or lower back area depending on the location of the compression over the neural elements.

Who does the laminectomy?

A laminectomy is performed by spine surgeons or surgeons who specialize in doing spine surgeries.

Will the laminectomy remove all my pain?

Laminectomy in the lower back is very helpful in patients who have radicular pain going down their legs. In most of the patients, the symptoms are well resolved, and these patients are able to get back to their normal life within six to ten weeks after the surgery.

What if, during my surgery, you encounter a different issue other than expected?

Usually, before the surgery, we discuss with the patient regarding all the possible spine issues that we may expect and how to manage them. If there is an unexpected issue, which has not been discussed earlier, we would go ahead and discuss it with the patient’s relative and treat it accordingly from there. If there is something which can wait, and is not detrimental to the patient, and relatives are not able to make decision on it, we may leave it for a later date to be discussed with the patient after the surgery.

How long is it possible to stay for back surgery?

Most of the patients with back surgery can be discharged within one to four days after the surgery depending on the type of surgery and the type of recovery that they have. Patients who undergo complex spine surgeries may need longer period of hospitalization and recovery.

Which pain medications will I be sent home with? What are the possible side-effects of these prescriptions?

Most of the patients with cervical spine surgery, will be sent with some narcotic pain medication to take care of their pain. These medications do have their multiple side-effects, which may be constipation, nausea, vomiting, impaired judgement, drowsiness, headache. Though patients who are treated with narcotic pain medication for acute pain, mostly do not lead to addiction, but these medications do have addiction potential.

Will you know before the surgery if I need a brace afterwards? If so, will I be fitted for one before the surgery?

Most of the patients with spine surgery do not need a brace. If we expect that the patient will need a brace, we will get the patient pre-fitted with a brace so that it is available immediately after the surgery. Occasionally the need for brace may be decided at the time of surgery. In such cases a brace is arranged in immediate post-operative period.

Will I need any other medical equipment like a walker when I go home? Should I get an adjusted bed or sleep downstairs?

Patient may need other medical equipment like walker or a stick. If that is required, patients are provided with such equipment in the hospital before their discharge and are trained how to use them by the physical therapist and occupational therapist. If the patient needs to use stairs, patients are trained by the physical therapist before they are let go home. If the patient needs an adjustable bed, they are informed about that. That can be done prior to the surgery. It is desirable for patients to stay downstairs for a few weeks if possible.

Who can I call if I have questions after the surgery?

In case patient has routine questions regarding after the surgery or regarding the surgery, they can call the physician’s office and talk to the nurse or secretary or the physician. If they’re not available on the phone, they can leave a voice mail and they will be answered later. In case the patient has a medical emergency, then they should not call the physician office but rather call 911 or get to the hospital ER as soon as possible.

How often will I see you after my surgery?

Patients are usually followed at two weeks, six weeks, three months, six months, and a year after surgery.

What symptoms would warrant a call to your office after the surgery?

If the patient develops problems like chest pain, breathing problems, sudden neurological deterioration, or any other emergency they should call 911, or go to the emergency room directly. Patients who develop worsening pain at the surgery site, discharge from the wound, fever; they should call in the office.

How long should I wait to bathe after the surgery?

Patients are usually asked to avoid bathing, until the incision heals, which may take two to three weeks. Patient can take shower after 72 hours of surgery with an impervious dressing in place. The dressing can be changes if the wound is visibly soaked. Patients are asked not to rub the area of surgery for about two to three weeks. They can gently dab it dry with a towel.

How long will I be out of work?

Patients with low demand work and desk job, can be back to work as soon as three to six weeks after the surgery depending on patient pain control as well as recovery. Patients who are in heavy lifting or control of heavy machinery or handyman job, may take three to four months, or even more to get back to work depending on their recovery from the surgery.

How soon after the surgery can I start physical therapy?

Patients after back surgery are usually started on physical therapy, if they need, depending on physician’s advice, at two to four weeks after the surgery. Many of the patients do not need physical therapy. A decision to go into physical therapy will depend on the surgery as well their recovery.

What if I get an infection?

If the patient has a superficial infection, few days of antibiotics will help heal these infections. Occasionally patient may develop deep infection. In these patients may need IV antibiotics for a longer period. If despite all efforts or in patients with rapid deterioration due to infection, surgery may be needed to help clean off the infection.

How common is surgery?

Most of the patients do not need surgery and can be treated with conservative means. When the patients do not respond to conservative measures, or if they have worsening neurological deficit, or worse pain, they may need surgery.

Will I have irreversible damage if I delay surgery?

Patients who develop neurological deficit in the form of weakness or involvement of bowel or bladder may have irreversible damage if the surgery is delayed enough.

When do I need fusion?

When patient has back pain or has a surgery in which enough bone is removed to destabilize the spine, in these cases patient may need a fusion surgery to stabilize the spine, as well as to alleviate the symptoms.

What are my risks of low back surgery?

General surgical risks of low back surgeries include bleeding, infection, persistence of pain, reversible/irreversible nerve damage leading to tingling, numbness, or weakness down the legs or involvement of bowel or bladder, failure of resolution of symptoms, failure of fusion, failure of implants. Most of the patients can undergo a safe surgery due to the development of vision magnification as well as refined surgical techniques. There are anesthesia risks also associated with this surgery.

When will I be back to my normal activities?

Though these things depend on the type of surgery patient has undergone, patient can usually be progressively back to their normal activities, starting from three to five days from surgery. Patients are encouraged to take care of their activities of daily living, as well as light household activities. Patients can get back to driving once they are free from pain medication and are able to sit for a duration of period for driving, which may take upto 2-3 weeks or more.

What type of surgery is recommended?

The type of surgery depends on the presenting complaint, examination findings, as well as imaging findings in the form of x-ray and MRI. Some patients may need to undergo just discectomy, or laminectomy, while others may need a fusion surgery on their back to relieve their symptoms. To know more about the type of surgery, the patient needs to discuss this with their spine surgeons.

How long will the surgery take?

Spine surgeries like discectomy and laminectomy usually last about one to one and a half hours. Spine fusion surgeries, may take longer periods, up to two and a half to four hours or more. It depends on type of surgery, and as well as the level of spine to be operated upon.

What is degenerative disc disease?

Degeneration means gradual damage of the tissue. Degenerative disc disease represents aging of the disc, either appropriate to the normal age of the patient, or maybe accelerated due to injury or chronic disease, or other factors like smoking, obesity.

What is Lumbar instability?

Lumbar instability means that the spine is not stable and there is excessive abnormal movement between two vertebrae. This is usually diagnosed by imaging in the form of X-rays, CT scan, or MRI of the patients. Instability may lead to compression of nerve roots causing radiculopathy with or without back pain.

What is Spinal Stenosis?

Spinal Stenosis means narrowing of the spinal canal. It is can be at the cervical or thoracic or lumbar level. Most common spinal stenosis is at lumbar level and it, when narrowed, can compress nerves, causing pain going down the legs, with or without tingling, numbness, weakness, or involvement of bowel or bladder.

What is sciatica?

Sciatica is another name for lumbar radiculopathy, in which patient has pain going down their legs. The pattern of pain depends on the nerve root involved, but the most common is pain going down the outer side of the thigh and leg into the foot.

What is lumbar disc disease? How is this problem diagnosed?

The diagnosis of Lumbar disc disease is made by history and examination of the patient. The confirmation of diagnosis is done by imaging in the form of X-rays and MRI. Occasionally the patient is having contraindication to MRI, patient may need to undergo a CT scan. When a CT scan is done, occasionally the patient may need to get injected with a dye before the CT scan and this is called CT myelography. Occasionally patient may need a CT scan along with MRI also.

When should I consider surgery for the back pain?

Most of the patients get treated with conservative means. In case the patient is not getting relief despite continuous conservative measures, or if there is worsening of pain associated with or without weakness or involvement of bowel or bladder, the patient may need surgical intervention in the form of surgery.

Am I a candidate for minimal-invasive spine surgery?

Some patients are good candidates for minimally-invasive spine surgery and they can get better with that. History, physical examination, as well as special investigations like X-ray and MRI, are needed in order to discuss regarding options of minimal invasive spine surgery. Some patients are not good candidates for minimal invasive spine surgery and doing such a surgery in such patients may lead to non-resolved solution of the symptoms or worsening.

Are there any warning symptoms?

Warning symptoms of lumbar disc disease include worsening pain, tingling and numbness, development of weakness, or worsening of weakness, involvement of bowel or bladder in the form of incontinence of urine or stools, presence of fever, unintentional weight loss. In such conditions patients should immediately seek medical attention.

Do you need any tests?

General blood workup is needed in most patients before the surgery. This will include blood counts as well as metabolic profile. Special tests may be needed in some patients if the physician has suspicion of some other disease. Most of the patients will have to undergo X-ray and MRI, or a CT scan before the surgery to confirm their diagnosis.

What are the possible surgical complications from a low back surgery?

Common complications of a low back spine surgery are bleeding, infection, leak of cerebral spinal fluid temporary or permanent neurological deficits, blindness, worsening of pain, failure of fusion, failure of implants. There may be risks due to the anesthesia also.

What is foraminotomies?

Foraminotomies is the surgery done from the back in the neck or the lower back area in which a small amount of bone is removed to increase the size of the foramen where the nerve roots pass to give more space to the nerve root and to relieve the symptoms. These surgeries do not involve removal of enough bones to require insertion of screws and rods to fuse the spine.

What are the risks of laminectomy?

Apart from the usual risks of having some back surgery, the risk of laminectomy includes injury to the nerve roots of the spinal cord, bleeding, injury to the sac, covering the spinal root or spinal cord leading to leakage of the fluid, persistence of pain or worsening, temporary or permanent worsening of symptoms. It may also lead to delayed restenosis as well as destabilization of the fragment leading to forward bending of the spinal column.

What is post laminectomy pain syndrome?

Post laminectomy pain syndrome usually involves the lower back and presents in patient who have undergone laminectomy for spinal stenosis. These patients, due to worsening of their degenerative condition or osteoarthritis of the back, start having pain involving the disc in their lower back. They may also develop flattening of the back due to weakness and muscle spasm.

Is laminectomy an outpatient surgery?

One or two level laminectomy of the lower back can be done through outpatient. Laminectomies more than two levels or laminectomies of the cervical spine or thoracic spine are usually performed in a hospital setting due to the complexity of the surgery.

What is the difference between a laminectomy and discectomy?

The disc is present in the front of the spinal cord or nerve roots and the lamina are present behind the spinal cord of the nerve roots. Discectomy involves surgery usually from the front, though it can also be performed from the back especially in the lower back and involves removal of the disc to remove the pressure from the front of the neural elements. Laminectomy on the other hand is performed from the back and involves removal of pressure from the neural elements from the back. Sometimes especially in the lower back area, both the surgeries can be combined and usually performed from the back.

What is laminectomy of the neck?

Laminectomy of the neck involves removing the lamina from the vertebrae or the bones of the neck. These laminae are present on the back of the neck and the surgery is done through the back of the neck. These patients also need to undergo fusion with screws and rods so as to prevent later complications of laminectomy. This is usually done for patients who have impingement of their nerves in the neck from the back side rather than the commoner form that is from the front.

What is thoracic laminectomy?

Thoracic laminectomy involves removal of the lamina from the back of the vertebrae or bones of the thoracic spine or the chest region. The surgery is done from the back and may or may not involve fixation with screws and rods. This surgery is usually performed for patients who have compression on their spinal cord in the thoracic spine.

What is cervical decompressive surgery?

Cervical decompressive surgery is removal of pressure that is on the spinal column or the spinal cord in the neck region. This can be performed from the front or from the back depending on the location of the compression on the spinal cord. This surgery may or may not be accompanied with fixation of the vertebrae using screws, rods or plates.

What is laminectomy and what is the purpose?

Laminectomy involves removal of the back of the vertebrae so as to remove pressure from the spinal cord or the spinal nerves in the vertebral column. This can be performed in the neck, chest, or lower back area depending on the location of the compression over the neural elements.

Who does the laminectomy?

A laminectomy is performed by spine surgeons or surgeons who specialize in doing spine surgeries.

What is laminoplasty of the neck?

The laminoplasty involves cutting of lamina on one side so as to open it up and fixing it in an open position with the use of mini plates so as to increase the size of the spinal canal and decrease the pressure on the spinal cord. This surgery is performed from the back of the neck and does not involve fusion of the neck thereby decreasing the restriction of movement of the neck as may be present after laminectomy and fusion surgery.

What is cervical spine foraminotomy?

Cervical spine foraminotomy is a minimal invasive surgery which is performed from the back of the neck for pinched nerve in the neck. These patient’s usually have radiating pain into the arm and the surgery helps in decreasing the pressure over the cervical spine nerve root to allow space for the nerve and eliminate the symptoms. This surgery if done in suitable candidate can avoid fusion surgery that is traditionally needed to decrease the pressure of the spinal roots.

These questions have been personally answered by:

Dr. Sebastian Heaven
Orthopedic surgeon at London Health Sciences Centre (LHSC)

I provide Orthopaedic patient care at several different locations, including a Regional Joint Assessment Centre, a Level 1 Trauma Centre and a District General Hospital. My scope of practice is broad and includes Trauma, Arthroplasty and Sports Orthopaedics.

My areas of special interest include Primary and Revision Arthroplasty, Periprosthetic Fracture Management and general orthopaedic trauma management in isolation and in the context of complex polytrauma patients. I also have clinical research interests in these areas, as well the development of interprofessional relationships between trauma team members and fellow healthcare professionals.

I have personally written all or most of what's on this page for Complete Orthopedics, and approve the use of my content.

Dr. Sebastian Heaven
Orthopedic surgeon at London Health Sciences Centre (LHSC)

I provide Orthopaedic patient care at several different locations, including a Regional Joint Assessment Centre, a Level 1 Trauma Centre and a District General Hospital. My scope of practice is broad and includes Trauma, Arthroplasty and Sports Orthopaedics.

My areas of special interest include Primary and Revision Arthroplasty, Periprosthetic Fracture Management and general orthopaedic trauma management in isolation and in the context of complex polytrauma patients. I also have clinical research interests in these areas, as well the development of interprofessional relationships between trauma team members and fellow healthcare professionals.

I have personally written all or most of what's on this page for Complete Orthopedics, and approve the use of my content.