Cam impingement is a hip joint shape difference where the femoral head–neck junction is less round than usual. It is commonly discussed as a cause of femoroacetabular impingement (FAI) and hip pain in active people. It can contribute to labral tears and cartilage wear when the hip moves into certain positions. Clinicians use the term to describe imaging findings and to guide evaluation and treatment planning.

Cam deformity is a shape change at the femoral head–neck junction (the “ball” of the hip joint). It creates a bony bump that can reduce the normal roundness of the femoral head. It is commonly discussed in femoroacetabular impingement (FAI), a cause of hip pain and limited motion. Clinicians use the term when evaluating hip symptoms, interpreting imaging, and planning treatment.

Calcar femorale is a thickened ridge of dense bone inside the upper femur (thigh bone) near the hip. It helps support the femoral neck, which is the narrow bridge between the femoral head and the shaft. Clinicians most often discuss it when interpreting hip imaging and planning hip fracture or hip replacement care. It is an anatomic structure, not a device or a standalone treatment.

Bursitis is inflammation or irritation of a bursa, a small fluid-filled sac near a joint. A bursa helps tissues glide smoothly when you move. Bursitis is commonly discussed in orthopedics, sports medicine, and physical therapy when evaluating joint-area pain. It can occur in the hip, shoulder, elbow, knee, heel, and other regions.

Buttock refers to the soft-tissue region on the back of the pelvis, below the waist and above the upper thigh. In everyday use, Buttock describes the rounded area formed mainly by the gluteal muscles and overlying fat. In clinical care, Buttock is a common location for pain descriptions, physical exam findings, and procedural landmarks. It is also an important area for movement, posture, and load transfer between the trunk and legs.

Brooker IV is the most severe grade in the Brooker classification system for heterotopic ossification around the hip. It describes extensive abnormal bone formation that appears to “bridge” the hip joint on X-ray. It is most commonly referenced after hip surgery, especially total hip arthroplasty (hip replacement). Clinicians use it as a shared language to describe severity and guide discussion of functional impact.

Brooker III is a grading term used in the Brooker classification for heterotopic ossification around the hip. It describes a more advanced level of extra bone formation seen on hip X-rays. It is most commonly used after total hip replacement and after significant hip trauma or surgery. Clinicians use it to communicate severity and to guide discussion about stiffness and function.

Brooker II is a radiographic (X-ray–based) grade used to describe heterotopic ossification around the hip. Heterotopic ossification means bone forms in soft tissues where bone does not normally belong. Brooker II is most commonly referenced after hip surgery, especially total hip arthroplasty (hip replacement). It helps clinicians communicate how much extra bone is present and how close it is to limiting motion.

Brooker I is the mildest grade in the Brooker classification for heterotopic ossification around the hip. It describes small “islands” of extra bone seen in the soft tissues near the hip joint on X-ray. It is most commonly used after hip surgery, especially total hip arthroplasty (hip replacement). It helps clinicians describe and track post-operative bone formation in a consistent way.

Brooker classification is a grading system used to describe **heterotopic ossification** around the hip. Heterotopic ossification means **extra bone forming in soft tissues** where bone normally does not grow. The Brooker classification is most commonly applied on **plain X-rays** after hip surgery or hip trauma. It helps clinicians and researchers communicate how extensive the bone formation looks on imaging.