LIVRE JDG 2012

S. Parratte, M. Ollivier, J.M.Aubaniac, J.N. Argenson

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survivorship as in our early experience all the

un-cemented femoral implants of the patella-

femoral have been revised.

Indication

The patient profile analysis for this type of

procedure is an important factor. Most of the

time, potential candidates are active and want

to stay active after the surgery and this is one of

their main expectations after the relief of the

pain (ref mobile bearing TKA). The first criteria

is the location of the pain. In fact, the physical

exam should analyse exactly the location of the

pain. When the lateral compartment is painful,

there is no indication for a combined medial-

UKA and patella-femoral arthroplasty. There is

also no indication in inflammatory arthritis of

the knee and post-traumatic arthritis may be an

indication as long as surgeons and patient alike

are aware of the higher rate of complication in

post-traumatic arthritis. The age, gender or the

weight of the patient should be considered but

are not represented strict limitations.

The indications for the procedure are: a

confirmed diagnosis of painful bicompartmental

osteoarthritis (Ahlback Grade 2 or greater) and

a preserved status of the lateral compartment

joint (based on clinical evaluation and stress-

radiographs). A preoperative range of knee

flexion greater than 100º associated with a full

range of knee extension, and finally a knee

clinically stable in the frontal and sagittal planes

are also considered as crucial for the indication.

A valgus or a varus deformity greater than ten

degrees as measured on the long-leg X-rays, or

a metaphysal tibial varus greater than 7 degrees

are also considered as a contra-indication. Varus

and valgus stress radiographs are systematically

performed to evaluate the lateral compartment

and the correction of the deformities. A full loss

of cartilage on the lateral compartment or a

fixed deformity observed on the stress

radiograph are considered as contra-indications.

We do perform an MRI to check the status of

theACL if there is any doubt during the physical

exam. Following this analysis, there is two

types of potential candidates. The first type is a

patient with a varus knee and a bone on bone

arthritis of the medial compartment and a

significant arthritis of the medial facet of the

patella-femoral joint. Most of this type of

patients are active male around sixty or younger.

The second type of patients has a bone on bone

patella-femoral arthritis of the lateral patella-

femoral joint with a patellar subluxation

associated with a painful arthritis (most of the

time albhack 2 or 3) of the medial compartment.

Most of the time, this type of patient are female

a little less active, around sixty or younger.

When the indication is confirmed following the

physical and radiological exam, the discussion

with the patient is important. We should take

the time to explain that the philosophy is to

conserve the cruciate ligaments and to replace

only the concerned compartment. It’s important

to note that the progression of the arthritis in the

lateral compartment is exceptional but not

impossible.

Approach

We perform a medial skin incision. The upper

limit is around two cm above the patella, the

knee in extension. The distal limit of the skin

incision is around two cm below the joint line,

the knee in flexion, medial to the anterior tibial

tubercule. The dissection should then be

performed against the superficial part of the

vastus medialis as deep as possible against the

muscle. The fatty “yellow line” between the

muscle and the retinaculum should be found

and open using a piker. A Homan retractor is

then inserted in the plane to reach the anterior

cortex of the femur and the anatomical plane

into the muscle fascia is opened proximally.

Distally, the electric cautery is used to prolong

the incision following the distal border of the

vastus medialis until the patella and then the

vertical part of the incision is performed until

around two cm below the joint line. Like for a

standard medial UKA, it’s important to not

perform any release of the MCL. The knee is

then brought in extension, the patella is sub-

luxed and the anterior cortex of the femur is

cleaned using the cautery. We do mark the

Whiteside line at this step using the cautery.

The knees in flexion, the osteophytes of the

intercondylar notch are removed to avoid any