Subchondral Cysts

What are subchondral cysts?

Acetabular subchondral cysts, also known as acetabular cysts or simply hip cysts, are a relatively uncommon but significant medical condition affecting the hip joint. These cysts develop within the subchondral bone, which is the layer of bone just beneath the cartilage in the hip joint’s acetabulum—the cup-shaped socket of the pelvis where the thigh bone (femur) articulates. Understanding acetabular subchondral cysts involves exploring their causes, symptoms, diagnosis, and treatment options.

What are the causes of subchondral cysts?

The exact cause of acetabular subchondral cysts remains uncertain, although they are commonly associated with degenerative joint diseases such as osteoarthritis. In osteoarthritis, the protective cartilage within the joint gradually wears away, leading to increased stress on the underlying bone. This increased stress can trigger various responses within the bone, including the formation of cysts.

Additionally, acetabular subchondral cysts may develop due to trauma or injury to the hip joint. Such injuries can cause damage to the cartilage and underlying bone, initiating the cyst formation process.

Other contributing factors to the development of acetabular subchondral cysts may include anatomical abnormalities of the hip joint.

What are the symptoms of subchondral cysts?

The symptoms of acetabular subchondral cysts can vary depending on their size, location, and severity. Some individuals may experience no symptoms at all, while others may have significant hip pain and mobility issues.

Common symptoms associated with acetabular subchondral cysts include:

1. Hip Pain: Persistent or intermittent pain in the hip joint, which may worsen with weight-bearing activities such as walking or standing.
2. Limited Range of Motion: Difficulty moving the hip joint through its full range of motion, often accompanied by stiffness.
3. Joint Stiffness: A feeling of stiffness or tightness in the hip joint, particularly after periods of inactivity.
4. Swelling: Swelling around the hip joint, which may be accompanied by warmth or redness.
5. Clicking or Catching Sensation: Some individuals may experience a clicking or catching sensation within the hip joint during movement.

It’s essential to note that the presence of acetabular subchondral cysts does not always correlate with the severity of symptoms. Some individuals may have extensive cyst formation but minimal symptoms, while others may experience significant pain and functional impairment with only small cysts present.

How are subchondral cysts diagnosed?

Diagnosing acetabular subchondral cysts typically involves a combination of medical history review, physical examination, and imaging studies. During the physical examination, Dr. Shane J. Nho will assess the range of motion of the hip joint and palpate the area for tenderness or swelling.

Imaging studies are crucial for confirming the presence of acetabular subchondral cysts and evaluating their size and location. Common imaging modalities used in the diagnosis of hip cysts include:

1. X-rays: X-rays provide detailed images of the bones and can reveal areas of bone loss or abnormal bone formation associated with cysts.
2. Magnetic Resonance Imaging (MRI): MRI scans offer high-resolution images of the soft tissues surrounding the hip joint, allowing for the detection of cysts and assessment of their impact on nearby structures.
3. Computed Tomography (CT) Scan: CT scans provide detailed cross-sectional images of the hip joint, offering additional information about the size and location of cysts.

In some cases, Dr. Shane J. Nho may pursue a diagnosis hip injection, involving the injection of a local anesthetic and/or a steroid into the hip joint to evaluate if and how the hip pain is alleviated.