Posterior acetabular rim refers to the back edge of the acetabulum, the “socket” part of the hip joint. It is a key bony boundary that helps contain and stabilize the femoral head (the “ball”). Clinicians commonly mention it in hip imaging reports, hip injury descriptions, and surgical planning. It is also discussed when evaluating hip instability, impingement, and certain acetabular fractures.

Pipkin fracture is a specific type of fracture of the femoral head, the “ball” of the hip joint. It is most often discussed in the setting of a traumatic hip dislocation, especially a posterior dislocation. The term is commonly used in orthopedic trauma to describe the fracture pattern and associated injuries. Clinicians use it to communicate severity and help plan evaluation and treatment.

Pincer morphology describes a hip shape where the socket (acetabulum) covers the ball (femoral head) more than expected. This extra coverage can contribute to femoroacetabular impingement (FAI), where hip motion causes abnormal contact in the joint. The term is most commonly used in orthopedic clinics, sports medicine, radiology reports, and hip preservation care. It is a description of anatomy, not a diagnosis by itself.

Pincer morphology imaging is the use of medical imaging to evaluate acetabular “overcoverage” of the hip socket. It helps clinicians see whether the rim of the socket may contact the femoral head-neck region during hip motion. It is commonly used when hip or groin pain raises concern for femoroacetabular impingement (FAI) or related labral injury. It is also used to plan treatment and to distinguish similar conditions that can look alike on symptoms alone.

A Pincer lesion is a hip joint shape problem where the socket side of the hip (the acetabulum) covers the ball side (the femoral head) too much or in the wrong orientation. This extra coverage can cause the rim of the socket to “pinch” the femoral neck during motion. It is most commonly discussed in the setting of femoroacetabular impingement (FAI) and related hip pain. Clinicians use the term in exams, imaging reports, and surgical planning conversations.

Pincer impingement is a type of hip “pinching” problem caused by extra coverage of the femoral head by the acetabulum (hip socket). It is commonly discussed under the broader term femoroacetabular impingement (FAI). It can contribute to hip or groin pain, limited motion, and mechanical symptoms in some people. It is used in orthopedics, sports medicine, radiology, and physical therapy to describe a specific hip shape and contact pattern.

Pincer deformity is a hip shape variation where the socket (acetabulum) covers the ball (femoral head) more than typical. It is commonly discussed as a cause of femoroacetabular impingement (FAI), a mechanical conflict during hip motion. The term is used in orthopedic clinics, sports medicine, and hip imaging reports to describe a structural finding. It can be associated with hip pain, labral injury, and cartilage wear in some people.

Piriformis tendon is the strong, fibrous end of the piriformis muscle where it attaches to bone. It sits deep in the buttock and typically connects the piriformis muscle to the upper femur near the greater trochanter. Clinicians discuss it in hip anatomy, deep buttock pain evaluations, and some hip and sciatic-nerve–related conditions. It may also be referenced during certain hip surgeries where the short external rotators are exposed or repaired.

Piriformis stretch is a general term for movements that lengthen the piriformis muscle in the deep buttock. It is commonly used in physical therapy and sports medicine for buttock pain and certain patterns of sciatica-like symptoms. It can be performed in several positions, such as lying on the back, sitting, or standing. Clinicians often pair it with an exam of the hip, pelvis, and lower back to identify the likely source of symptoms.

Piriformis syndrome is a clinical term used when buttock pain and sciatica-like symptoms are thought to come from the piriformis muscle region. It is most commonly discussed in orthopedics, sports medicine, and physical therapy when hip-area structures may be irritating the sciatic nerve. The idea is simple: a deep buttock muscle may contribute to nerve irritation and referred pain down the leg. Because several conditions can look similar, Piriformis syndrome is often considered a working diagnosis after other causes are assessed.