Right total knee replacement using Smith & Nephew Journey components A size 6 femur was used, a size 6 tibial tray, 10-mm polyethylene insert and a 35-mm cemented polyethylene patellar button Medtronic optical system computer navigation

PREOPERATIVE DIAGNOSIS:                Severe osteoarthritis of the right knee.

POSTOPERATIVE DIAGNOSIS:                         Severe osteoarthritis of the right knee.

OPERATION PERFORMED:                    1.         Right total knee replacement using

                                                                                    Smith & Nephew Journey components.

                                                                                    A size 6 femur was used, a size 6 tibial

                                                                                    tray, 10-mm polyethylene insert and a

                                                                                    35-mm cemented polyethylene patellar

                                                                                    button.

2.                  Medtronic optical system computer navigation.

anesthesia:                                             Regional.

PROCEDURE IN DETAIL:                                    After the smooth induction of anesthesia, the patient was given intravenous Ancef antibiotic prophylaxis.  The right lower extremity was then prepped and draped in the usual sterile manner. After exsanguination with a sterile Esmarch bandage, a previously placed pneumatic tourniquet was inflated to 350 mmHg.

An incision was made starting just proximal to the superior pole of the patella. It extended down to the tibial tubercle. Blunt dissection was carried out. A limited medial arthrotomy was performed.  The proximal border of the tibia was subperiosteally exposed and the medial and parapatellar ligament was released.  A portion of the retropatellar fat pad was sharply dissected from the knee joint. The patella was partially everted and a limited cut was made, paralleling the extensor mechanism. The synovium was then cleared off the anterior aspect of the distal femur. Two parallel pins were placed in the midshaft of the femur and the tibia.

The Medtronic optical computer navigation system was then assembled, calibrated, and preoperative anatomical landmarks were obtained as per protocol. Once alignment was calculated, a standard distal femur cut was made, removing 11 mm of bone, keying off the low point on the medial portion of the distal femur. Alignment was verified. The knee was flexed and the extramedullary alignment jig was positioned in place, paralleling the anterior border of the tibia. Bone was removed, keying off the low point of the medial tibial plateau.

After the bone edges were smoothed, the remains of the posterior horns of the medial and lateral meniscus, anterior and posterior cruciate ligaments were resected. The bone edges were smoothed and with a the presence of spacer blocks, it was confirmed the knee was balanced in extension and that our tibial cut was exactly perpendicular to the anterior border of the tibia in full extension.

Sizing was carried out and appropriate femoral cuts were made. Spacer blocks were used to confirm the knee was balanced in both flexion and extension. The knee was flexed. The tibia was subluxed anteriorly. The size 6 tray was centered over the tibial tubercle. Peg and keel cuts were made. The tray fit nicely. Central portion of the bone was removed from the distal femur with a drill.  Various inserts were trialed and with a 10-mm insert, full extension and nearly 135 degrees of flexion were obtained with excellent varus/valgus stability throughout the range of motion.

After a final patellar cut was made, a 35 lollipop was placed in the proximal and medial position. Peg cuts were made. The patellar button was trialed. The knee was placed through a range of motion and the patella tracked down the center of the femoral trochlea throughout the range of motion using a no-hands technique.

All of the trial components were removed and while cement was being vacuumed premixed, the wound was vigorously irrigated with the pulsatile lavage system and packed with Kerlix soaked with peroxide. In sequential fashion, the tibial tray and femoral component were cemented in place. A trial insert was placed over the tibia. The knee was placed into extension to compress the components and then brought out to 90 degrees, at which point, excess cement was removed. The knee was placed back into extension to allow the cement to harden. After the patellar button was cemented in place, the tourniquet was released. Bleeding sites were cauterized and any extra protruding synovium was trimmed.

The synovium of the distal femur was then closed with #2 Vicryl. The trial insert was removed. The knee was inspected, irrigated, and the real insert was secured in place. Final range of motion was noted to be full extension with neutral alignment and the knee could flex to 140 degrees. There was excellent stability throughout the range of motion.

The medial retinaculum was now closed over a Hemovac with #2 Vicryl. The subcutaneous tissue was closed with 2-0 Vicryl. The skin was closed with staples. The wound was washed and dried. A sterile compression dressing was applied. The drain was then injected with 20 mL of Naropin, 6 mg of Decadron, 0.2 mL of epinephrine, 500 mg of Zinacef and 10 mg of morphine. The drain will be clamped for several hours to allow the fluid to seep into the soft tissue.

At this point, anesthesia was reversed and the patient was brought to the recovery room, having tolerated the procedure well without complications. Sponge count and needle counts were correct. Estimated blood loss was 100 mL.  Tourniquet time was 40 minutes.