What is osteolysis?

Osteolysis is a progressive condition where bone tissue is destroyed. In this process, bones lose minerals (mostly calcium), softens, degenerates and become weaker.

What causes osteolysis?

Osteolysis occurs when cells in the bone called osteoclasts increase their activity and break down the surrounding minerals. There are different types of osteolysis, and each has specific mechanisms that lead to this increase in osteoclast activity and the resulting condition of demineralization.

What are the different types of osteolysis?

The most common types of osteolysis, which are generally unrelated to one other, include:

• distal clavicular osteolysis – commonly called “weight lifter’s shoulder”
• periprosthetic osteolysis – which affects some people who have had joint replacement surgeries
• acro-osteolysis (rare) – in which bone in the distal phalanges (fingers or toes) of the hand or feet erode and degenerate

Distal clavicular osteolysis: What is weight lifter's shoulder?

Distal clavicular osteolysis – also known as osteolysis of the shoulder (distal clavicle), AC joint osteolysis or “weight lifter’s shoulder” – affects the acromioclavicular joint (AC joint), at the top of the shoulder. This progressive condition destroys bone tissue in the clavicle. The AC joint is where the acromion – a part of the scapula (shoulder blade) meets the clavicle (collarbone) at its distal (outer) end. They are connected by the acromioclavicular ligament. The connection by this ligament enables you to raise your arm above your head. In some people, the distal end of the clavicle at the AC joint can begin to lose calcium, soften and erode.

Osteolysis of the AC joint is most common among weight lifters and other athletes who do significant weight training. But it can also affect people who frequently lift heavy objects overhead (such as construction or factory workers) or otherwise exert force on the shoulder by repetitive overhead movement (such as tennis or squash players, competitive swimmers, etc.).

What causes weight lifter's shoulder?

The specific cause of distal clavicular osteolysis is not fully understood. However, it is thought to be caused by one or a combination of predisposing factors, such as:

• repetitive injuries to the AC joint or distal clavicle
• repetitive motions with heavy weights (hence the name “weight lifter’s shoulder”)
• a combination of the long-term wear on the shoulder joint combined with some predisposing joint condition, such as rheumatoid arthritis
• other underlying diseases or chronic conditions that can affect the AC joint, such as infections
  (rarely) a single blunt force trauma to the clavicle (impact such as by a fall or physical blow)

Among weight lifters, it is thought that certain activities overload the joint, causing microtrauma where the damage doesn’t have time to heal between lifting sessions. This leads the bone to dissolve rather than heal.

What are the symptoms of weight lifter's shoulder?

Key symptoms of this condition include:

sharp pain in the AC joint or collarbone during activity
continued dull aching or tenderness of these same areas during inactivity
inflammation (swelling) in the shoulder or collarbone area

Distal clavicular osteolysis tends to progress rather slowly and starts with dull pain, tenderness, or stiffness in the shoulder that worsens over time. The pain typically presents in the anterior region of the shoulder at the AC joint, and becomes worse with activities that involve heavy lifting, pushing, or throwing. Over time, up to approximately three centimeters of bone may erode.

How do I know if I have weight lifter's shoulder?

The diagnosis of distal clavicle osteolysis can be usually made by physical examination, although imaging tests may be used to confirm the diagnosis or rule out other causes of shoulder pain.

What is the treatment for weight lifter's shoulder?

Treatment is usually nonsurgical, and includes icing and resting the shoulder, taking anti-inflammatory medications, and undergoing physical therapy. In some instances, surgery may be needed. Treatment focuses on reducing pain and minimizing activities that exacerbate the condition while allowing time for the bone to rebuild (remineralization).

Standard conservative treatment includes:

• rest
• icing
• NSAIDs (nonsteroidal anti-inflammatory drugs)

It is also recommended that patients who are smokers quit to help with the bone remineralization process (this means the restoring of calcium in the bone). It may take several months for the bone to recover.

What is the surgery for weight lifter's shoulder?

If conservative treatments do not effectively remineralize the clavicle, surgery to remove part of the end of the clavicle may be required to alleviate symptoms.

Periprosthetic osteolysis

A second type of osteolysis can occur as a complications of joint replacement surgery. Most patients recover from joint replacement surgery with no complications. But occasionally, polyethylene or other materials in a joint implant can wear down. When this happens, debris can accumulate in the surrounding joint tissue. This, in turn, causes inflammation that can result in degeneration of the bone.

In people who have had hip, knee or other joint replacements, a key sign of periprosthetic osteolysis is an aseptic loosening of the joint prosthesis (that is, a loosening of the implant without any indication of infection).

This condition often causes no symptoms until very late, after there has been extensive bone loss. For this reason, joint replacement patients should have periodic follow-up X-rays of their joint. When they do occur, symptoms of osteolysis around a joint prosthesis are generally related to the associated loosening of the implant. They include:

• pain
• weakness
• Stiffness

If you have had a joint replacement, and after time begin experiencing the above symptoms, your surgeon may first order tests, X-rays and MRI imaging to see if you have a postsurgical infection which, separate from periprosthetic osteolysis, can also lead to joint pain and loosening of an implant.

If caught early, various treatments may be used to treat the inflammation and prevent further osteolysis. If bone loss is deemed extensive, the treatment may require surgery to revise the joint replacement (for example hip revision or knee revision).

Acro-osteolysis

Acro-osteolysis is where bone in the distal phalanges (fingers or toes) of the hand or feet erode and degenerate. Osteolysis may be caused by an underlying inflammatory condition. This can include infections, genetic disorders and problems with the endocrine system. Acro-osteolysis is seen frequently in patients who have certain underlying rheumatic and inflammatory conditions, including:

• dermatomyositis
• juvenile idiopathic arthritis
• psoriatic arthritis
• Raynaud’s phenomenon
• scleroderma

Acro-osteolysis is also found in people who have:

• experienced extensive use of vibratory power tools (such as pneumatic drills)
• been exposed to vinyl chloride
• elevated levels of parathyroid hormone

Acro-osteolysis, in some cases (such as in people who have inflammatory conditions such as scleroderma or severe Raynaud’s disease), may be accompanied by an associated condition known as digital ischemia. This is where the tissue is not getting enough blood flow, and there can be death of skin cells which could lead to ulcerations of the extremities. In other cases, acro-osteolysis may not be associated with digital ischemia.

The most prevalent symptom is pain in the fingers or toes. If there is associated digital ischemia, there can also be color change or breaks in the skin. X-rays are the standard method used to diagnose acro-osteolysis.
Treatment for acro-osteolysis mainly relates to treating the underlying condition. In cases where there is both acro-osteolysis and decreased blood flow to the extremities, local wound care and treatments that can increase blood flow to the extremities can be used.
 

The hip is a ball-and-socket joint. The ball, at the top of your femur (thighbone) is called the femoral head. The socket, called the acetabulum, is a part of your pelvis. The ball moves in the socket, allowing your leg to rotate and move forward, backward and sideways. A hip fracture is a break in either the upper portion of the femur or of the pelvis.

Femoral hip fractures

The term "broken hip" usually refers to a fracture of the ball side of the hip joint, that is, a break in the upper femur, generally in one of three areas:

• the femoral neck (just below the femoral head) – called an intracapsular fracture (most common)
• immediately below the femoral neck – called an intertrochanteric fracture
• the upper femoral shaft below the femoral neck – called a subtrochanteric fracture (least common)

Hip fractures frequently occur in the elderly, people affected by disease, or from direct trauma. Femoral hip fractures can be treated relatively easily, with our without surgery, depending on the severity of the injury.

Pelvic and acetabular hip fractures

A fracture of the acetabulum or other portion of the pelvis is often a more serious injury that requires prompt surgery (in some cases, multiple surgeries). These types of breaks are often the result of high-impact trauma such as a car vehicle accident or a bad fall. However, they can occur during a lower-impact fall, primarily in older adults who have fragile bones due to osteoporosis.

In fractures of this type, the femoral head is often driven through the acetabulum because of the impact of the fall or accident. If the fracture causes the femoral head to pop outside the acetabulum, this is known as a dislocated hip.

Treating acetabular fractures is complex because this section of bone is very close to:

• the major blood vessels to the legs
• the sciatic nerve (the major nerve that arises from the lower spine and provides sensation and movement to the leg and foot)
• the intestines, the ureter and the bladder
   

A subchondral cyst is a fluid-filled space inside a joint that extends from one of the bones that forms the joint. This type of bone cyst is caused by osteoarthritis. It may require aspiration (drawing the fluid out), but the arthritis condition usually must also be addressed to prevent further cyst formation.

Hip impingement, also known as femoroacetabular impingement, is a condition in which there is abnormal alignment of and contact between the bones that form the ball and socket of the hip joint. The result is increased friction during hip movements that may damage the joint.

Patients often complain of pain in the groin after prolonged sitting or walking. Many athletes often describe pain in the groin with deep flexion or rotation of the hip during activity. Occasionally, a popping or clicking in the front of the hip is described. Pain may also radiate along the side of the thigh and in the buttocks. It is important to rule out other causes of pain in this area which may originate in the low back or abdomen.

Treatment of hip impingement begins with conservative, nonsurgical methods. Rest, activity modifications, careful use of anti-inflammatory medications, and a course of physical therapy are often successful in alleviating symptoms. An injection of the hip joint with anesthetic and steroid can also provide some relief, as well as diagnostic information in patients with symptoms which are unresponsive to treatment. When surgery is necessary, hip impingement can usually be treated with arthroscopic hip surgery.
 

Hip replacement is highly successful surgery in which portions of the hip joint are replaced with prostheses (implants).

What is hip replacement surgery?

Hip replacement is the removal and replacement of portions of the pelvis and femur (thighbone) that form your hip joint. It is performed primarily to relieve hip pain and stiffness caused by hip arthritis.

This procedure is also sometimes used to treat injuries such as a broken or improperly growing hip, and for other conditions.

How do you know if you need a hip replacement?

If you have these arthritis symptoms, you should consider a hip replacement:

• severe hip pain that is not relieved by medication and that interferes with your work, sleep or everyday activity
• hip stiffness that restricts motion and makes it difficult to walk

Hip anatomy

The hip is a ball-and-socket joint. The ball, at the top of your femur (thighbone) is called the femoral head. The socket, called the acetabulum, is a part of your pelvis. The ball moves in the socket, allowing your leg to rotate and move forward, backward and sideways.

In a healthy hip, soft-tissue called cartilage covers the ball and the socket to help them glide together smoothly. If this cartilage gets worn down or damaged, the bones scrape together and become rough. This condition, osteoarthritis, causes pain and restricts motion. An arthritic hip can make it painful to walk or even to get in or out of a chair. If you have been diagnosed with hip arthritis, you may not need surgery. Nonsteroidal anti-inflammatory drugs (NSAIDs) and/or physical therapy may provide relief. But, if these efforts do not relieve symptoms, you should consult an orthopedic surgeon.

What are the different types of hip replacement surgery?

The three major types of hip replacement are:

• total hip replacement (most common)
• partial hip replacement
• hip resurfacing

The most common type of hip replacement surgery is called a total hip replacement (also called total hip arthroplasty). In this surgery, worn-out or damaged sections of your hip are replaced with artificial implants. The socket is replaced with a durable plastic cup, which may or may not also include a titanium metal shell. Your femoral head will be removed and replaced with a ball made from ceramic or a metal alloy. The new ball is attached to a metal stem that is inserted into the top of your femur. (Learn more about types of hip implants.)

Two other types of hip replacement surgeries are each generally appropriate for patients of specific age groups and activity levels:

• Partial hip replacement (also called hemiarthroplasty) involves replacing only one side of the hip joint – the femoral head – instead of both sides as in total hip replacement. This procedure is most commonly done in older patients who have fractured their hip.
• Hip resurfacing of the femoral head and socket is most commonly done in younger, active patients.

Hip replacement surgical methods

There are two major surgical approach methods for performing a total hip replacement:

• the posterior approach (more common)
• the anterior approach (sometimes called the "mini-anterior approach" or "muscle-sparing hip replacement")
   

To begin the operation, the hip replacement surgeon will make incisions on either the back (posterior) or front (anterior) of the hip. Both approaches offer pain relief and improvement in walking and movement within weeks of surgery. In some instances, the orthopedic surgeon may choose to employ robotic technologies during the surgery.

How should I prepare for hip replacement surgery?

There are certain steps patients can take both before and after surgery to improve recovery time and results. It is important to follow the instructions and guidance provided by your orthopedic surgeon, medical team and rehabilitation therapist.

Can hip replacement be done as an outpatient?

Most patients will stay in the hospital one or two nights after surgery. Some patients may be able have same-day hip replacement and return home after an outpatient procedure.

How long does hip replacement surgery take?

Total hip replacement surgery takes about one and a half hours. Most patients also stay in the hospital for one or two days after the procedure.

How long does it take to recover from a hip replacement?

Your rehabilitation will begin within 24 hours after surgery. Most hip replacement patients progress to walking with a cane, walker or crutches within day or two after surgery. As the days progress, you will increase the distance and frequency of walking. Full recovery generally takes anywhere from two to eight weeks, depending on the patient's general health and other factors.

Can I have both hips replaced at the same time?

Yes, healthy patients younger than 75 years old who have no history of cardiopulmonary disease may be able to have both hips replaced at once. In some cases, however, it may be better to stage the surgeries.

What are the risks in hip replacement surgery?

The surgery is very safe, but every surgery has risks, and infection is the most serious. You should ask your surgeon what the surgical infection rate is for hip replacements at the hospital or facility where you will have your surgery.

What are hip implants made of?

There are three separate implants: the stem, the ball and the socket.

• The stem, made out of metal (usually titanium or cobalt-chrome) is inserted into your natural thighbone.
• The ball is usually made out of polished metal or ceramic, and fits on top of the stem.
• The socket is usually a combination of a plastic liner and a cobalt-chrome or titanium backing.

Will my new hip set off the metal detector at the airport?

Today's sensitive screening machines will detect the implant but can also effectively identify it. The machine operator will know that it is an implant rather than an unauthorized metal object contained outside the body.

It is still helpful to tell airport security that you have had a hip replacement before entering the screening machine. You may also ask your doctor's office if they can provide a card that identifies that you have received a hip implant that contains metal.

How long do hip implants last?

Generally speaking, a hip replacement prosthesis should remain effective for between 10 and 20 years, and some can last even longer.

Results vary according to the type of implant and the age of the patient. In a 2008 study of more than 50,000 patients who had THR surgery at age 55 or older, between 71% and 94% still had well-working implants after 15 years.

When a hip implant does need to be replaced because it has loosened or worn out over time, this requires what is called hip revision surgery.

How soon after surgery can I resume driving?

Most patients can resume driving by six weeks after surgery.

What should I look for in a hip replacement surgeon?

When looking for an orthopedic surgeon to perform your hip replacement surgeon, it’s important to do your research and check the surgeon’s credentials, experience and reputation. It is also important to research the hospital or facility where you will have your operation, as well as its supporting staff, such as the anesthesiologists.