Orthopedic Medical Glossary

Hip Procedures

9 terms

A surgical technique for hip replacement that accesses the hip joint from the front of the body, working between muscles rather than cutting through them. This muscle-sparing approach typically allows same-day walking and eliminates post-operative hip precautions.

A muscle-sparing hip replacement approach that accesses the hip from the side (lateral) through a single small incision, sparing key muscles and tendons. It offers some benefits of the anterior approach with a different surgical pathway.

A minimally invasive procedure that uses a small camera (arthroscope) and specialized instruments inserted through small incisions to diagnose and treat hip joint problems such as labral tears, femoroacetabular impingement (FAI), and loose bodies.

A broad term encompassing surgical procedures to rebuild or restore the hip joint, including hip replacement, hip resurfacing, and complex revision surgery. It may also refer to reconstruction after trauma or developmental conditions.

A bone-conserving alternative to total hip replacement where the damaged surface of the femoral head is capped with a metal prosthesis rather than being removed entirely. The acetabulum is still resurfaced with a metal cup.

A hip replacement performed through a smaller incision than traditional surgery, with less disruption to surrounding soft tissues. The direct anterior approach is the most minimally invasive hip replacement technique.

A surgical approach to hip replacement that accesses the joint between muscles rather than cutting through them. The name reflects the rapid recovery — many patients walk the same day and resume light activities within 1–2 weeks.

A complex surgical procedure to replace a failed or worn-out hip implant with new components. Revision surgery may be needed due to implant loosening, infection, dislocation, wear, or bone loss over time.

A surgical procedure that replaces both the femoral head (ball) and the acetabulum (socket) of the hip joint with artificial components made of metal, ceramic, and/or polyethylene. It is performed to relieve pain and restore function in patients with severe hip arthritis.

Knee Procedures

5 terms

A minimally invasive procedure using a small camera and instruments inserted through small incisions to diagnose and treat knee problems such as meniscus tears, cartilage damage, and loose bodies.

A knee replacement that replaces only the damaged compartment of the knee, preserving the healthy cartilage and ligaments. It is appropriate when arthritis is limited to one compartment (medial, lateral, or patellofemoral).

A partial knee replacement that replaces only the patellofemoral compartment — the area where the kneecap (patella) meets the thigh bone (femur). It is used when arthritis is isolated to this compartment.

Surgery to replace a failed or worn-out knee implant. This is a more complex procedure than the original knee replacement, often requiring specialized implants, bone grafts, or augmentation to address bone loss.

A surgical procedure that replaces all three compartments of the knee joint (medial, lateral, and patellofemoral) with artificial components. The damaged cartilage and bone are removed and replaced with metal and polyethylene implants.

Surgical Techniques

8 terms

A surgical procedure that permanently fuses the bones of a joint, eliminating movement. It is typically used as a salvage procedure when joint replacement is not feasible.

The surgical reconstruction or replacement of a joint. Total hip arthroplasty and total knee arthroplasty are the medical terms for total hip and knee replacement, respectively.

Surgical techniques that use computer technology to enhance precision in implant positioning, alignment, and ligament balancing. MAKO robotic surgery is a form of computer-assisted surgery.

A real-time X-ray imaging technique used during surgery to visualize bones and implant positioning. In hip replacement, fluoroscopy allows the surgeon to confirm implant size, position, and leg length during the procedure.

A technology that provides tactile resistance to the surgeon's hands during robotic surgery, preventing the cutting instrument from moving beyond the pre-planned boundaries. This ensures bone removal stays within the planned margins.

The process of adjusting the tension of the ligaments around a joint during knee replacement to ensure proper stability and range of motion. Proper balancing is critical for a natural-feeling knee.

A surgical approach that accesses the joint by working between muscles rather than cutting through them. This technique reduces tissue trauma, post-operative pain, and recovery time.

A surgical procedure that cuts and reshapes bone to realign a joint, typically used to treat angular deformities or early arthritis. High tibial osteotomy (HTO) is used for knee realignment.

Anatomy

10 terms

A ring of cartilage that surrounds the rim of the acetabulum, providing stability and cushioning to the hip joint. Labral tears can cause hip pain and may require arthroscopic repair.

The socket-shaped cavity in the pelvis that forms the socket of the hip joint. In hip replacement, the damaged cartilage is removed and a metal cup with a liner is placed in the acetabulum.

The smooth, white tissue that covers the ends of bones where they meet at joints, allowing frictionless movement. In osteoarthritis, this cartilage wears away, causing pain and stiffness.

The ball-shaped top of the femur (thigh bone) that fits into the acetabulum (socket) of the pelvis to form the hip joint. In hip replacement, the femoral head is removed and replaced with a prosthetic ball.

The thigh bone, the longest and strongest bone in the body. The top of the femur forms the ball of the hip joint, and the bottom forms the upper part of the knee joint.

Two C-shaped pads of cartilage (medial and lateral) in the knee that act as shock absorbers between the femur and tibia. Meniscal tears are common knee injuries that may require arthroscopic treatment.

The small bone in front of the knee that protects the joint and improves the leverage of the quadriceps muscle. In knee replacement, the patella may be resurfaced or left intact depending on the patient's condition.

The tendon that connects the quadriceps muscle to the patella. In knee surgery, the surgical approach may involve this tendon. Some approaches minimize disruption to this tendon for faster recovery.

A group of small muscles behind the hip joint that provide stability. In posterior hip replacement, these muscles are cut and repaired. In the direct anterior approach, they are completely preserved.

The larger of the two lower leg bones (shin bone). The top of the tibia forms the lower part of the knee joint. In knee replacement, the tibial surface is resurfaced with a metal baseplate and polyethylene insert.

Implants & Devices

9 terms

An implant fixed to bone using polymethylmethacrylate (PMMA) bone cement. This technique is often used in patients with softer bone or poor bone quality.

An implant that relies on bone growing into its porous surface for fixation, rather than being held in place with bone cement. Most modern hip and knee implants use cementless fixation.

A hip implant bearing where both the femoral head and the socket liner are ceramic. This combination offers the lowest wear rate of all bearing options but may produce occasional squeaking.

A hip implant bearing combination where the femoral head is ceramic and the socket liner is polyethylene. This combination offers low wear rates and is suitable for most patients.

A metal alloy commonly used in joint replacement implants for its strength, durability, and biocompatibility. It is used for femoral heads, knee components, and hip stems.

A specialized orthopedic operating table designed for direct anterior hip replacement. It allows the operative leg to be positioned for optimal access to the hip joint and includes carbon-fiber components for intra-operative fluoroscopy.

A durable plastic material used as the bearing surface in joint replacements. In hip replacement, it lines the acetabular cup; in knee replacement, it serves as the spacer between metal components.

An artificial device that replaces a missing or damaged body part. In orthopedics, prostheses replace the surfaces of joints such as the hip and knee, typically made of titanium, cobalt-chromium, ceramic, and polyethylene.

A lightweight, strong, and biocompatible metal used in joint replacement implants. Titanium implants integrate well with bone through a process called osseointegration.

Recovery & Rehabilitation

9 terms

The ability to walk. Early ambulation — walking with assistance soon after surgery — is a key goal after joint replacement and is associated with faster recovery and fewer complications.

A machine that gently moves the knee through a controlled range of motion after knee replacement surgery. It helps prevent stiffness and improve flexibility during early recovery.

A blood clot that forms in a deep vein, typically in the leg. It is a risk after orthopedic surgery and is prevented with blood thinners, compression stockings, and early mobilization.

Movement restrictions after posterior hip replacement to prevent dislocation. Patients are told to avoid bending the hip past 90 degrees, crossing legs, or sitting in low chairs for 6–12 weeks.

A structured program of exercises and movements designed to restore strength, range of motion, and function after surgery or injury. PT is essential after hip and knee replacement.

A structured exercise and optimization program completed before surgery to strengthen muscles, improve nutrition, and prepare the body for recovery. Research shows prehab improves post-operative outcomes.

A potentially life-threatening condition where a blood clot breaks free and travels to the lungs. It is a rare but serious risk after joint replacement surgery.

The full movement potential of a joint, measured in degrees of flexion (bending) and extension (straightening). Restoring ROM is a key goal of both surgery and rehabilitation.

The ability to put body weight on the operated leg. After direct anterior hip replacement, patients can typically bear full weight immediately. After traditional approaches, weight bearing may be restricted.

Conditions & Diagnostics

15 terms

A condition where the blood supply to a bone is disrupted, causing the bone to die. In the hip, AVN of the femoral head is a common reason for hip replacement in younger patients.

A lay term for advanced osteoarthritis where the articular cartilage has completely worn away, causing the bones of the joint to rub directly against each other. This is typically the stage at which joint replacement is recommended.

An injection of corticosteroid medication into a joint to reduce inflammation and pain. It is a conservative treatment option for arthritis that may delay the need for surgery.

An imaging test that uses X-rays from multiple angles to create detailed cross-sectional images. In MAKO robotic surgery, a CT scan is used to create a 3D model of the joint for surgical planning.

When the ball of a joint comes out of the socket. After hip replacement, dislocation is a risk, particularly with the posterior approach. The direct anterior approach has a significantly lower dislocation rate.

A condition where the bones of the hip joint have an abnormal shape, causing them to rub against each other during movement. Over time, this can damage the joint and lead to arthritis.

An injection of a gel-like substance into the knee joint to provide lubrication and cushioning. It is used as a conservative treatment for knee arthritis.

A difference in the length of the legs, which can occur after hip replacement. Careful pre-operative planning and intra-operative measurement help minimize this risk.

When an implant loses its fixation to bone, causing pain and instability. Implant loosening is a long-term risk that may eventually require revision surgery.

An imaging test that uses magnetic fields and radio waves to create detailed images of soft tissues such as cartilage, ligaments, tendons, and labrum. It is used to diagnose soft tissue problems in the hip and knee.

The process by which bone grows directly into the surface of an implant, creating a strong biological bond. This is how cementless implants achieve long-term fixation.

The most common form of arthritis, characterized by the progressive wear and tear of articular cartilage in joints. It causes pain, stiffness, swelling, and reduced range of motion. It is the primary reason patients seek joint replacement.

Arthritis that develops after a joint injury, such as a fracture. The damage to cartilage and altered joint mechanics can lead to arthritis years after the original injury.

An autoimmune disease that causes chronic inflammation of the joints, leading to cartilage and bone damage. It can affect the hip and knee and may eventually require joint replacement.

An imaging test that uses radiation to create pictures of bones. X-rays are the primary diagnostic tool for evaluating arthritis and joint damage.

Robotic Technology

4 terms

The use of CT scan data to create a 3D virtual model of the patient's joint before surgery. This model is used to plan implant size, position, and alignment specific to the patient's anatomy.

A robotic-arm assisted surgery system (by Stryker) that uses CT-based 3D modeling to create a personalized surgical plan. The robotic arm guides the surgeon with haptic feedback during bone preparation, ensuring sub-millimeter accuracy.

Another robotic surgery system used in knee replacement, developed by Zimmer Biomet. It uses real-time data rather than pre-operative CT scans for surgical planning.

A pre-defined zone created during MAKO surgical planning that limits the robotic arm's movement. The saw cannot cut beyond this boundary, protecting healthy bone and soft tissue.