All topics
- What it is
- Who it helps
- Timing
- The procedure
- What a hemiarthroplasty is
- Hemi vs total hip
- Recovery after hip fracture
- Patient journey
- Recovery supplies
- Finding a surgeon
- Insurance and costs
- Questions to ask
- Implant designs
- Side-by-side
- Robotics and navigation
- US manufacturers
- What the evidence says
- Value analysis
- Resources
- Glossary
- References
Terms
Glossary
- Arthroplasty
- Joint replacement surgery. Total hip arthroplasty (THA) is a total hip replacement.
- Acetabulum
- The socket of the hip, part of the pelvis.
- Femoral head
- The ball at the top of the thighbone, or the artificial ball that replaces it.
- Femoral neck fracture
- A break in the narrow part of the thighbone just below the ball. Also called an intracapsular fracture.
- Hemiarthroplasty
- Replacing only the ball side of the hip, keeping the natural socket. Mainly used for hip fractures.
- Unipolar / bipolar
- Two types of hemiarthroplasty head: a single solid ball, or a ball inside a shell that moves at two surfaces.
- Cup (shell) and liner
- The metal hemisphere placed in the socket and the smooth insert inside it.
- Stem
- The metal part fitted inside the thighbone that holds the ball.
- Bearing
- The surfaces that move against each other, such as a ceramic ball on a polyethylene liner.
- Dual mobility
- A bearing with a small ball inside a larger plastic ball, designed to lower the risk of dislocation.
- Cemented / cementless
- Fixing an implant with bone cement, or with a rough surface that bone grows onto.
- Direct anterior approach
- Reaching the hip from the front. The posterior approach is from the back; the lateral approach is from the side.
- Hip precautions
- Movement restrictions, such as not bending past 90 degrees, once routinely given to lower dislocation risk.
- Dislocation
- When the ball comes out of the socket. Usually needs to be put back by a doctor.
- Leg length and offset
- The length of the leg and the distance from the center of the hip to the thighbone, both restored during surgery.
- Osteonecrosis (avascular necrosis)
- Bone death from loss of blood supply, which can collapse the ball of the hip.
- Periprosthetic joint infection (PJI)
- Infection around a joint replacement.
- Periprosthetic fracture
- A break in the bone around an implant.
- Revision
- A second operation to replace or fix part or all of a joint replacement.
- Venous thromboembolism (VTE)
- A blood clot in a vein (DVT) that can travel to the lungs (pulmonary embolism).
- Delirium
- Sudden confusion, common in older adults after surgery or a hip fracture.
- 510(k) clearance
- The FDA pathway for most implants, based on being substantially equivalent to an existing device.