What is Osteoid Osteoma? What Are Its Symptoms? How Is It Diagnosed and Treated?

Are you experiencing severe bone pain that wakes you up at night? This could be a symptom of osteoid osteoma, a benign bone tumor commonly seen in young people aged 15-20. Accounting for 10% of benign bone tumors, this condition is 2-3 times more common in males than in females. This tumor, which is usually smaller than one centimeter, can cause serious discomfort.

In this article, you will find everything you need to know about osteoid osteoma symptoms, causes, diagnosis, and treatment.

What is Osteoid Osteoma?

Osteoid osteoma is a type of benign tumor that develops in the bone. It appears as a small, round lesion in the bone tissue. Its size is usually less than one centimeter. Larger similar structures are called osteoblastoma.

Characteristics of Benign Bone Tumors

Although osteoid osteoma, which accounts for 10% of benign bone tumors, is called a tumor, it does not have the property of spreading in the body. Since it is not malignant, it does not turn into bone cancer. Therefore, it does not pose a life-threatening risk.

The tumor usually forms in the outer part of the bone, in the region called the cortex. However, it can also be seen under the cortex or in the middle part of the bone. It is found as a single lesion and is not expected to exist elsewhere.

Osteoid osteoma can cause the formation of an abnormal bone material called osteoid bone in the region where it is located. It has a radiolucent center and a sclerotic structure around it, which is called the nidus. There is no possibility of growth or transformation into a malignant state.

The pain experienced can sometimes be confused with growing pains. However, there is an important difference between them. While growing pains are felt in various parts of the body, osteoid osteoma pain occurs intensely in the same localized spot.

In Which Age Group and Gender Is It More Common?

Osteoid osteoma is a condition more frequently encountered during childhood and adolescence. It is usually seen in individuals between the ages of 10-20. The majority of cases consist of children under 20 years of age. It is especially more common in active and mobile individuals.

There is a significant difference in gender distribution. It is 2-3 times more common in males than in females. For every two or three male patients, approximately one female patient is encountered. Although the exact cause is unknown, it is thought that hormonal factors or minor traumas that boys are more frequently exposed to may be triggers.

In Which Bones Does It Occur?

Osteoid osteoma can develop in any bone of the body. However, it most commonly occurs in long bones. It is especially concentrated in the region between the hip and the knee.

The most common bones where it is seen are:

Thigh bone (femur)

Shin bone (tibia)

Arm bones (humerus)

Spine

Pelvis

In more than half of the cases, the area around the knee is affected. It is usually found around the hip joint at the upper end of the thigh bone. It can also rarely be seen in the jaw, wrist, metatarsal bones, and heel bone.

What Are the Symptoms of Osteoid Osteoma?

Osteoid osteoma symptoms show a characteristic pattern. The pain starts mildly at first, but its intensity increases as weeks and months pass. The patient can clearly point to the location of the pain with a single finger.

Severe Bone Pain That Increases at Night

The most prominent feature is bone pain that increases at night. The person, who does not experience major problems during the day at school, work, or play, wakes up with severe pain when they go to bed at night. When the body rests, the focus within the bone produces pain-causing chemicals called prostaglandins. These chemicals stimulate nerve endings and dilate blood vessels, resulting in pain intense enough to wake one from sleep.

The other important feature of the pain is its response to medication. When aspirin or similar drugs are used, the pain decreases significantly after 20-30 minutes. Patients state that the pain "cuts like a knife" after taking the medication. This is one of the fundamental points that distinguishes osteoid osteoma from other bone conditions.

Regional Swelling and Tenderness

Over time, tenderness that increases with touch develops in the area where the tumor is located. Local tenderness is common in children and adolescents. Also, mild swelling and a bump may be noticed in the area. This swelling accompanies the pain and creates regional sensitivity.

Movement Limitation and Muscle Contractions

If the tumor is located near a joint, movement limitation may occur. Joint stiffness and a decrease in range of motion cause difficulty in daily activities. Similarly, muscle contractions occur due to pain.

In spinal placement, muscle spasms and curvature can be seen. Tumors located in the spine can lead to painful scoliosis in children by causing muscle spasms due to pain. In addition, muscle weakness occurs over time due to constant pain. Muscle atrophy leads to a decrease in movement skills.

Appearance of Leg Shortening and Limping

Limping is one of the common symptoms in children. Muscle contractions can give the appearance of shortening in the leg where the tumor is located. Children who have difficulty using their legs due to pain may walk on their tiptoes. Limping indicates involvement in long bones.

In intra-articular placements such as the hip joint, pain can be felt in other areas. For example, a tumor in the hip can cause pain in the knee.

What Are the Causes of Osteoid Osteoma?

The causes of osteoid osteoma are not fully known. Scientific research conducted to date has not been able to establish a definitive cause. However, some factors that may potentially trigger the tumor can be mentioned.

Trauma and Physical Factors

The relationship between trauma and osteoid osteoma is not clear. Some experts argue that there is no direct link with trauma. However, it is noteworthy that there is a history of trauma before the tumor in many cases.

In a series of 36 cases, a history of trauma was recorded in 15 patients at the beginning. In another study, symptoms started with swelling after trauma in 11 of 46 cases. In the literature review, 15 cases of osteoid osteoma developing after trauma were reported, and it was emphasized that a history of significant trauma should be noted.

In case of pain in areas prone to trauma such as the hands and feet, traumatic bone or soft tissue damage is primarily considered. Therefore, the diagnosis of osteoid osteoma may be delayed in these areas. Seeing osteoid osteoma after trauma is not a common situation in the literature. If the pain persists despite treatment, the possibility of osteoid osteoma should be considered.

Intense physical stress, environmental toxins, and minor bone traumas are also among the external factors that may trigger the process. In addition, some medications used and hyperactivity can be counted as possible triggers.

Genetic Predisposition

Genetic predisposition is among the effective factors in the formation of osteoid osteoma. Observing familial transmission in some individuals suggests that genetic background may play a role in this tumor. However, a definitive genetic cause has not yet been identified.

Disruptions in cellular processes that play a role in bone development may trigger this condition. Skeletal construction errors at the microscopic level may also be effective in its formation. It is noteworthy that this benign bone tumor appears more frequently, especially during periods of rapid bone growth. This suggests that the process is related to growth dynamics.

As a result, there is no clear information about the causes of osteoid osteoma. Although trauma, genetic factors, and errors in bone formation processes are shown among possible causes, a definitive cause cannot be demonstrated. No familial or environmental cause has been identified.

How Is Osteoid Osteoma Diagnosed?

Osteoid osteoma diagnosis is made with clinical findings and imaging methods. Since the size of the tumor is usually as small as a grain of rice, the detection process requires attention. Symptoms must be evaluated correctly, and this benign bone tumor should not be overlooked.

Physical Examination and Patient History

The diagnostic process begins with taking the patient's history and a physical examination. During the examination performed by an orthopedics and traumatology specialist, pressure is applied to the painful area. Tenderness becomes evident, and in some cases, indirect findings such as muscle spasms or mild swelling draw attention. Although patient history and physical examination provide strong clues, advanced imaging methods are needed for a definitive diagnosis.

Initial Evaluation with X-ray

X-ray is the first-line examination, but it is not always sufficient. Some patients come with an X-ray film in their hands and say, "It came out clean, but my pain is not going away." This is a very common situation. In classic cases, thickening in the bone and a small transparent hole in the middle can be seen. However, especially in intra-articular placements or complex bone structures such as hands and feet, X-rays may be insufficient, and the tumor may be overlooked. When X-ray is used alone, osteoid osteoma can be missed.

Detailed Examination with Computed Tomography (CT)

The gold standard method is computed tomography. CT shows the bone structure in the finest detail. It allows for the detection of the exact location, size, and core of the tumor with millimeter precision. With this method, which shows the internal structure of the bone very well, structures smaller than 1 centimeter can be easily examined. CT images are definitely used when planning treatment.

Typically, an intracortical nidus smaller than 2 centimeters, which can be centrally calcified, radiolucent, or low-density, and surrounding cortical thickening with sclerosis are seen on CT. It can fully determine the extent of the lesion and allows for the definition of its dimensions. It is very useful in cases where the nidus cannot be detected radiographically due to intense periosteal reaction.

Magnetic Resonance (MR) Imaging

MR is effective in understanding the relationship between soft tissues and bone. It provides important information, especially for evaluating the environmental effects of the tumor and edema. It enables a detailed examination of the bone marrow and the tissue around the bone. However, MR can sometimes be confusing. Because it shows the edema around the tumor as very extensive, the situation may be perceived as worse than it is. It can be mistakenly confused with bone inflammation or malignant tumors. Diagnostic errors of up to 35% have been reported when used alone. CT is indispensable for definitive diagnosis and detection of the nidus.

Bone Scintigraphy

Bone scintigraphy is a method that can be used if a definitive diagnosis has not been made and a whole-body scan is required. It contributes to the diagnosis by imaging the intense cellular activity in the bone tissue. By showing the area where there is an intense increase in activity, it contributes to the recognition and localization of the lesion. In suspicious cases, a typical 'double density' image can be detected.

How Is Osteoid Osteoma Treated?

After the diagnosis is made, treatment options are determined according to the severity of the patient's complaints and the location of the tumor. There are three basic methods: medication, radiofrequency ablation, and surgical intervention.

Pain Control with Medication

Simple painkillers can control osteoid osteoma pain. Especially the use of aspirin responds well to symptoms. The pain decreases significantly 20-30 minutes after taking the medication.

However, medication does not eliminate the tumor, it only suppresses the pain. Side effects such as heartburn, gastrointestinal bleeding, kidney problems, and hypertension may occur with long-term use. If the pain is not severe and does not affect daily life, the patient can be followed up with medication. Because the tumor can heal spontaneously over the years.

Radiofrequency Ablation (Minimally Invasive Method)

Today, the gold standard treatment method is radiofrequency ablation. The success rate is around 90-95%. It is a minimally invasive procedure and is performed under computed tomography guidance.

During the procedure, the tumor is reached with a special needle through a half-centimeter hole. The tumor is burned at approximately 90 degrees for 6 minutes with the heat energy generated at the tip of the needle. This high temperature destroys the tumor cells and the nerve endings that cause pain.

The advantages of radiofrequency ablation are quite numerous. It does not require incisions or stitches, the procedure time is short, and discharge is provided on the same day. The patient can start walking immediately after the procedure. A rapid and effective decrease in pain complaints is expected. The risk of complications is around 3%.

However, this method cannot be applied in some special cases. If the tumor is very close to nerves, skin, spinal cord, or growth plate, the heat may damage surrounding tissues.

Surgical Treatment (Open Surgery)

Open surgical method is preferred in special cases. Surgery comes into play when radiofrequency cannot be applied due to the location of the tumor or if there is doubt in the diagnosis. It is frequently used in hand, foot, and superficial cases.

The goal of the surgery is to completely eliminate the nidus. A skin incision is made over the tumor area, and the lesion in the bone is removed. Sometimes, 1-2 centimeters of bone may have to be removed along with the tumor. In this case, a screw or platinum may be placed to reduce the risk of fracture.

In cases where the tumor cannot be completely removed, pain may recur after temporary relief. In this case, a re-operation may be required.

Post-Operative Recovery Process

After radiofrequency ablation, the patient is usually discharged on the same day. One can return to daily life without the need for activity restriction. The pain disappears completely in the first 3 days; in some patients, mild aching may continue for up to 2-3 weeks.

In the open surgical method, the patient stays in the hospital for 1-2 days. The recovery period varies between 1-6 weeks depending on the size and location of the tumor. Especially in weight-bearing bones, heavy sports and activities that will strain the bone should be avoided for 3 months after the procedure.

Problems That May Occur If Not Treated

Osteoid osteoma that is not treated in time causes chronic pain. Unrelenting pain makes daily life seriously difficult. Limitation in joint movements and a decrease in range of motion are observed.

Muscle weakness occurs due to constant pain. Due to muscle contractions, an appearance of shortening in the leg may occur, and these contractions may become fixed. Posture disorders and decreases in movement skills emerge.

Usually, the tumor can limit itself until the end of the growth age and can heal within 3-7 years. However, the agony endured during this long period is not acceptable.

Frequently Asked Questions About Osteoid Osteoma

After receiving a diagnosis, patients ask many questions about their condition. These questions are usually about the degree of danger of the disease, long-term risks, and the treatment process.

Is osteoid osteoma dangerous?

No, it is not dangerous. Osteoid osteoma is a benign bone tumor and does not threaten life. It does not show the property of spreading in the body. However, if not controlled, chronic pain and movement limitation may occur. Your life comfort is negatively affected due to severe pain. Therefore, there is no life-threatening risk, but it is recommended to be treated.

Does osteoid osteoma turn into cancer?

There is no risk of this tumor turning into cancer. The possibility of malignancy is negligible. It does not turn into malignant bone tumors and does not spread to the body. However, it can be confused with some malignant bone tumors. Pathological evaluation is required for definitive differentiation.

Does osteoid osteoma go away on its own?

In some cases, symptoms may decrease over the years. It is known that the tumor matures and fades on its own between 3 and 7 years. Usually, this period can take an average of 3 years. The lesion heals by calcifying over time. However, suffering from pain every night during this long waiting period is not acceptable. If not treated, the quality of life is significantly affected. Therefore, treatment is recommended for patients.

Can osteoid osteoma recur?

If the tumor is completely removed, it rarely recurs. When the tumor is completely destroyed by open surgery or radiofrequency ablation, there is no recurrence. However, recurrence risks ranging from 10% to 20% have been reported in the literature. In cases where the tumor cannot be completely removed, pain may recur after temporary relief. When a second radiofrequency ablation session is applied in recurring cases, the success rate is almost 100%. The risk of recurrence is related to the treatment method and the location of the tumor.

How long does osteoid osteoma surgery take?

The surgical procedure is usually completed between 1 and 2 hours. In open surgeries, the time varies between 45 minutes and 1 hour. The radiofrequency ablation procedure takes less than 1 hour. The duration of the operation depends on the location and size of the tumor. Patients are usually discharged on the same day after radiofrequency ablation.

In Summary, Osteoid Osteoma

Although osteoid osteoma is a benign bone tumor, it can seriously affect your quality of life. However, there is no need to worry. It has become quite easy to get rid of this condition with modern treatment methods. Especially thanks to radiofrequency ablation, the procedure is completed within the same day, and your pain disappears rapidly.

If you are experiencing severe bone pain that wakes you up at night, do not ignore the situation. With early diagnosis and correct treatment, you can be protected from complications such as chronic pain, movement limitation, and muscle weakness. If your complaints continue, be sure to consult an orthopedics specialist and have the necessary imaging tests done.