- SPECIALIST ORTHOPAEDIC SURGEON | MELBOURNE, VIC | ALBURY, NSW | MORNINGTON, VIC |
- 03 9421 6133
- Melbourne & Mornington VIC |
- Albury, NSW
Medial Pivot Implants Total Knee Replacement
Designed to replicate natural knee motion for a more stable, confident recovery
Your knee is not just a simple hinge, it’s a highly complex joint that rolls, glides, and pivots through a wide range of movements. In a healthy knee, the medial (inner) side serves as a stable pivot point, while the lateral (outer) side moves more freely to allow rotational motion. Traditional implants often ignore this distinction, replacing it with a more mechanical or symmetrical design. This can result in unnatural movement patterns, instability, or difficulty trusting the joint during everyday activities.
Medial pivot implants, like the GMK Sphere used by Dr Jason Hockings, are designed to more closely mimic this natural motion, helping to deliver a more stable and confident outcome after total knee replacement surgery.
What are medial pivot implants?
Medial pivot implants are a modern class of total knee replacement prosthesis engineered to replicate the natural kinematics of your knee. These implants create a fixed pivot point on the medial (inner) side and allow controlled motion on the lateral (outer) side, recreating the natural rolling and gliding your knee performs when walking, bending, or turning.
The GMK Sphere by Medacta is a leading example of this design with key features including:
- A stable ball-and-socket interaction on the medial side
- A lateral side that allows rotational freedom
- Anatomical shaping for a more natural fit
- Deep-dish inserts for enhanced stability during movement
This design helps restore confidence in your knee’s performance whether you’re walking on uneven ground, turning quickly, or climbing stairs.
Why Dr Jason Hockings uses medial pivot implants
Dr Hockings has chosen medial pivot technology for most of his total knee replacement surgeries because of the clear advantages it offers in replicating native knee biomechanics. He often uses the GMK Sphere implant because:
- It supports kinematic alignment, restoring your pre-arthritic joint lines
- It improves joint stability across the full range of motion
- It reduces mid-flexion instability, which can occur with traditional implants
- It is associated with higher patient satisfaction, particularly with activities that involve twisting, turning, or kneeling
Dr Hockings’ use of medial pivot implants is always personalised, carefully matched to your anatomy, goals, and lifestyle using advanced planning and surgical technologies.
Key design features of medial pivot implants
Medial pivot designs differ significantly from older-generation implants in the way they interact with your bone and soft tissue. Notable features of the GMK Sphere include:
- Spherical medial compartment: Mimics the natural “ball-in-socket” pivot of the inner knee, reducing side-to-side wobble.
- Freedom of movement on the lateral side: Accommodates natural gliding and rotation as your knee bends and straightens.
- Deep-dished polyethylene insert: Offers improved stability and reduces long-term wear.
- Anatomically contoured femoral and tibial components: Allow for a more accurate fit and smoother tracking during movement.
Medial Pivot Implant materials and fixation methods
Medial pivot implants used by Dr Hockings are made from high-performance materials, including:
- Cobalt-chromium or titanium for the femoral (thigh bone) component
- Highly porous titanium for the tibial baseplate, designed to promote bone ingrowth
- Cross-linked polyethylene for the insert, engineered for durability and low wear
In most cases, Dr Hockings prefers cementless (press-fit) fixation, which allows your bone to naturally grow into the porous surface of the implant. This method may offer better long-term fixation, especially in patients with strong bone quality.
How medial pivot implants support better outcomes
Clinical research and 10+ years of global patient data support the benefits of medial pivot technology. Reported outcomes include:
- Increased mid-flexion stability, improving function during activities like rising from a chair
- More natural-feeling motion, reducing awareness of the implant during everyday tasks
- Improved proprioception, helping patients better perceive joint position and movement
- Lower revision rates compared to some traditional implant designs
- High patient satisfaction, particularly with low-impact, functional activities like walking, swimming, and gardening
A personalised approach with every surgery
Dr Hockings combines medial pivot technology with the latest surgical innovations to maximise outcomes for each patient. His approach includes:
- Kinematic alignment: Tailors the positioning of your implant to match your original, pre-arthritic joint anatomy
- Patient-specific instrumentation (PSI): Custom 3D-printed cutting guides based on your CT scan for precise bone preparation
- Subvastus surgical approach: A minimally invasive, muscle-sparing technique that helps speed up recovery
This combination ensures that your knee replacement is tailored, accurate, and designed to help you regain confidence in your movement.
Is a medial pivot implant right for you?
Not every implant suits every patient. During your consultation, Dr Hockings will carefully assess your imaging, bone quality, knee alignment, and activity goals. If a medial pivot design is determined to be the most appropriate for restoring your function and achieving a natural-feeling knee, it will be included in your personalised surgical plan.
If you’re experiencing ongoing pain, stiffness, or reduced movement that is affecting your daily activities or quality of life, a thorough orthopaedic assessment can help determine the cause and guide the most appropriate treatment options for your situation.