Trunnionosis is wear and corrosion at the junction where the femoral head connects to the femoral stem in a total hip replacement. It can release microscopic metal debris and metal ions into the hip area. Clinicians most often discuss Trunnionosis when evaluating pain, swelling, or tissue reactions after hip arthroplasty.

Trendelenburg after hip replacement refers to a hip drop or trunk-lean pattern seen when standing or walking after a hip arthroplasty. It is commonly described using the **Trendelenburg sign** (a physical exam finding) or **Trendelenburg gait** (a walking pattern). In plain terms, it usually indicates that the muscles on the outside of the hip are not stabilizing the pelvis well. Clinicians use it in follow-up visits and rehabilitation settings to assess hip abductor function.

Trendelenburg sign is a clinical finding seen during a simple one-leg standing test. It describes a drop of the pelvis on the side of the lifted leg. It usually suggests weakness or poor function of the hip abductor muscles on the standing leg. It is commonly used in orthopedic, sports medicine, and physical therapy exams for hip and gait concerns.

Trendelenburg gait is a walking pattern where the pelvis drops on the “swing” side when a person stands on the affected leg. It usually reflects weakness or impaired control of the hip abductor muscles, especially the gluteus medius and gluteus minimus. Clinicians commonly use it as a visible clue during a gait exam and in physical therapy or orthopedic evaluations. People may notice it as a “hip drop,” a side-to-side sway, or a limp that worsens with fatigue.

Trochanteric tubercle is a small bony prominence on the upper (proximal) femur. It sits near the greater trochanter, along the ridge between the greater and lesser trochanters. Clinicians use it as an anatomic landmark and as a reference point for muscle and tendon attachment. It most often comes up in hip anatomy, imaging interpretation, and hip or femur surgery discussions.

The Trochanteric region is the outer upper area of the thigh where the femur’s bony prominences (the trochanters) sit near the hip. It is best known as the area around the **greater trochanter**, a palpable bump on the outside of the hip. Clinicians use the term to describe pain location, examine tendon and bursa problems, and plan imaging or procedures. Patients often recognize it as “side-of-hip” tenderness or pain when lying on one side.

Trochanteric pain syndrome is a common cause of pain on the outside of the hip. It is a clinical umbrella term for conditions around the greater trochanter (the bony prominence on the side of the upper thigh bone). It is used in orthopedics, sports medicine, and physical therapy to describe lateral hip pain patterns. It often involves the hip abductor tendons and nearby soft tissues rather than the hip joint itself.

Trochanteric nonunion is when a break or surgical cut at the hip trochanter does not heal into solid bone. The trochanter is the bony “bump” on the upper femur where important hip muscles attach. This term is commonly used after hip surgery or a trochanteric fracture when healing is delayed or fails. It can be seen on imaging and may or may not cause symptoms.

Trochanteric fossa is a small hollow on the inner (medial) side of the femur’s greater trochanter near the hip. It serves as an attachment area for a deep hip muscle tendon. Clinicians also use it as an anatomical landmark when reading imaging or planning certain hip and femur procedures. It is discussed in orthopedics, sports medicine, and anatomy because of its proximity to key hip stabilizers.

Trochanteric fixation nail is an internal metal implant used to stabilize certain hip and upper femur fractures. It sits inside the thigh bone (femur) and is anchored with screws into the femoral neck and head. It is most commonly used for fractures around the trochanteric region near the hip. It is placed during orthopedic surgery to support bone healing and restore alignment.