Uniglide™
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Unicompartmental Knee Replacement Mk III surgical technique

Congruency of the Uniglide mobile bearing Restoring Biomechanics Component stability Instrumentation design Mobile bearing option Fixed bearing option Operative summary Pre-operative assessment Medial procedure Tibial preparation Tibial resection Check tibial alignment Tibial sizing Femoral sizing Femoral drilling Femoral reaming: Measure - Ream - Trial technique 14 Further femoral preparation 15 Mobile bearing option (Steps 12-15) 16 Final femoral preparation 16 Implantation of definitive mobile bearing components 17 Fixed bearing option (Steps 16-18) 18 Fixed bearing final femoral...

Uniglide™ History I Technology I Versatility The unicompartmental knee replacement for any surgical need |3

Uniglide™ Introduction The Uniglide Unicondylar Knee Replacement (UKR) is available as either a mobile or fixed bearing design. Fixed and mobile options are provided for medial compartment UKR. A fixed option is provided for the lateral compartment UKR. The triple radius design of the femoral component offers bone conservation and maintains both the facet and load centres of the natural femur, thereby providing the promise of a more natural kinematic function. The overall design and precise instrumentation make Uniglide an extremely effective and versatile unicompartmental knee system. 18°...

Mobile bearing option The concept of a mobile bearing unicondylar knee system has been established as offering a low contactpressure system without introducing a degree of constraint which would transfer loads to the tibial plateau4,5,6. The design of the Uniglide mobile bearing offers the mobility required to accommodate the rotation and translation of the femoral condyles, while providing the stability against the bearing dislocation required of a modern mobile bearing knee system. The stability against the bearing dislocation is provided by the deep dish produced by the concave...

Uniglide™ Operative summary g. EM alignment of the femoral component d. Check tibial alignment

j. Femoral posterior resection k. Starter reamer for femur

Uniglide™ Indications The Uniglide Mobile Bearing Unicondylar Knee System is indicated for use in patients with osteoarthritis limited to the medial compartment of the knee and is intended to be implanted with high viscosity bone cement. The Uniglide Fixed Bearing Unicondylar Knee System is indicated for replacement of the articulating surfaces of one tibio-femoral compartment of the knee where this has been affected by primary degenerative disease, post traumatic degenerative disease or damage due to previous surgical intervention and the anterior and posterior cruciate ligaments are...

Fixed bearing Uniglide – medial compartment Fixed bearing Uniglide – lateral compartment Preparation The leg should be draped free with the foot exposed, and usually with a tourniquet in place. At least 120° of flexion must be possible, either by hanging the tibia or on the operating table. The X-rays should be templated, but final measurement and sizing are performed intra-operatively. Incision Any of three incisions may be used for a medial bearing: 1. A full medial arthrotomy with the patella dislocated laterally. This allows total inspection of the joint and best access for implant...

Uniglide™ Medial procedure Indication of resection depth Step 1. Tibial preparation Place the tibial alignment cutting block against the anterior aspect of the tibia and align the jig as shown. Initially, correct rotation should be achieved so that the jig rests in the sagittal plane and the tibial clamp points towards the medial malleolus. Surgeons should try to replicate the individual patient’s tibial slope, (distally, the cutting jig should be approximately 1- 2cm further from the front of the tibia than proximally). A 7° posterior slope is built into the jig. Insert the stylus into the...

Step 3. Tibial resection The sagittal cut is made parallel to the guide and down onto the tibial cutting block with the reciprocating saw pointing towards the femoral head. This cut should be made as close as possible to the ACL. The direction of this cut is crucial to avoid later tracking problems. For this reason it is advised that the head of the femur is marked with a clip. Resect the top of the tibia taking great care not to undercut the ACL. Remove the resected bone. This is most easily done with the knee in 20°-30° of flexion. Note: The posterior cortex needs to be cut but this must...

Reference medial malleolus Step 4. Check tibial alignment Check that there is adequate space in flexion for at least a 7mm spacer lollipop to be inserted easily. The 7mm spacer lollipop here represents a combined tibial tray and insert thickness. If the spacer lolliopop cannot be inserted easily, further tibial resection will be required. 7mm = 4mm insert + tibial template thickness Step 5. Tibial sizing Place the check plate on the cut surface and ensure correct alignment using the rod, which should be directed towards the medial malleolus of the tibia and should indicate a 7° posterior...

Point to the femoral head Parallel to femoral canal Step 6. Femoral sizing Step 7. EM femoral alignment Impact the tibial trial firmly using the C-arm impactor. If the joint space is tight, the plastic foot may be removed to ease its insertion. Pre-operative templating should be checked using the femoral sizing guides, and the appropriate size selected. If borderline, choose the smaller size. Note: Choose the appropriate size and use the dedicated fixed or mobile tibial template to prepare the tibia. The fit for the femoral component is referenced off the posterior condyle and the anterior...

Deficiency = Extension gap - Flexion gap Step 8. Femoral drilling Once correct alignment has been achieved, with the knee at 97°, drill the smaller femoral anchorage hole and insert the T-pin or leave the drill in situ. Drill the larger posterior hole to its stopped depth. Remove the femoral alignment jig. Step 9. Femoral reaming: Measure - Ream - Trial technique Step 9 (i). Measuring for deficiency Any deficiency in the distal femoral condyle is determined by measuring the existing flexion and extension gaps using the spacer lollipops. The degree of deficiency is the extension gap minus...