Introduction


The goal of total knee arthroplasty is to give a patient with end stage degenerative joint disease of the knee a painless, stable and functional joint. Broadly speaking, the indications for this operation are radiographically confirmed disease, good rehabilitation potential, a willingness on the part of the patient to assume the risks of surgery and the absence of any contraindications. Poor patient selection and inadequate postoperative rehabilitation can certainly mar an excellent surgical result. These important issues, nonetheless, are not the focus here. Rather, the surgical details will be reviewed—recognizing that mastery of technique is only one facet of the complete package of knowledge, skills and attitudes needed to be a good surgeon.
The surgical operation can be broadly divided into the following sections.

  1. Preparation. The goal of this phase of the operation is to ready the patient for surgery (assuming that all of the prior preparation was adequately completed). This means that the entire extremity must be correctly prepped and draped; the instruments are where they are needed to be; the lighting is aimed correctly; the bumps and bolsters to the table are correctly attached; and that all are ready to proceed.
  2. Soft tissue Exposure. The soft tissue exposure of the knee is a phase of the operation perhaps most underrated by novices. The surgical incision must be correctly placed relative to the palpable landmarks. Next, the sharp dissection must be carried down to the layer of the extensor mechanism, but not through it. Dead space must be avoided. An arthrotomy must be created with enough soft tissue remaining to repair it, and without unnecessarily violation of the longitudinal fibers of the quadriceps. The patellar tendon must not be avulse. Ligaments, blood vessels and nerves must be preserved and protected. Soft tissues must be balanced.
  3. Tibial preparation. The bony resection of the proximal tibia must be done with precision. The goal is to create a platform perpendicular to the shaft of the tibia to accept the tibial tray. If there is minimal bone or cartilage loss on one side, tibial preparation typically requires a 10 millimeter cut off the less-affected side with a small amount of bone taken off the side with more extensive loss. Chasing bony defects with large cuts creates far more problems than simply using blocks, wedges or even bone grafts. Preservation of bone stock is mandatory, as many patients will live long enough to need revision.
  4. Femoral preparation. This part of the operation involves cutting small amounts of bone off all surfaces of the distal articular femur to prepare the bone for the prosthesis. Not only size but orientation, alignment and rotation are determined.
  5. Patellar preparation. The patella is resurfaced routinely. The goal here is to resect enough bone to avoid “overstuffing” the joint, but not to resect so much bone that the remaining patella is prone to fracture. Also, attention to tracking is essential: placing the patella prosthesis slightly medially, relative to the bone underneath, or performing a lateral release may improve tracking.
  6. Implanting and Cementing. Implanting and cementing are not particularly difficult, but make sure that the surfaces are dry and clean; the components are as close to the bone as possible; and that all excess cement is removed.
  7. Closure. Rehabilitation of the newly reconstructed knee demands motion. Thus, the repair of the arthrotomy and the closure of the overlying soft tissues must be robust. The knee joint itself must be “water tight.” Avoid dead space. Last, all absorbable sutures must be placed sufficiently far from the skin that they won’t “spit” from the wound.

There are many ways to perform a knee replacement. What follows is an annotated operative note on how we like to do it.

Operative Note

Note 1
What should be listed here? The operative report should also include a brief comment [not rendered in the text here] that you obtained informed consent by reviewing with the patient the nature of the diagnosis, the alternatives to treatment and the risks and benefits of the various options. You should also note that you re-examined the patient just prior to surgery; confirmed that no contra-indication had arisen and that the patient reiterates consent for the procedures; and that you signed the operative site.

Patient: XXXXXXXX

Diagnosis: End stage degenerative joint disease, left knee

Procedure: Total Knee Arthroplasty

Note 2

In a genuine operative note, you would list here the manufacturer of the implant and the size of the components used. In fact, retrieving that information may be the only reason a op-note is ever read.
Surgeon: Craig Israelite, MD

Anesthesia: General, supplemented by femoral nerve block

Perioperative antibiotics: Ancef, 2 gm

Tourniquet: 58 minutes at 350 mm Hg

Complications: None.

Preparation

The patient was taken to the operation room, it confirmed that the left side was the affected side and pre-operative antibiotics were administered. general anesthesia supplemented by a femoral nerve block was established . The patient was placed in the supine position. A small bump was positioned underneath the buttock of the operative extremity . A tourniquet was placed high on the thigh and pre-set to 350 mmHg for 60 minutes. A “paint-roller” bump was placed on the operative side of the operating room table at the level of the tibial tubercle.

Photo 1


Table set up. A bump is placed under the ipsilateral hip (obscured by the sheet) and the paint-roller under the knee at the level of the tibial tubercle. This device allows the knee to be held in flexion with minimal support form assistant necessary.
The opposite lower extremity was taped to the OR table The leg was then scrubed with iodine soap and then painted it with Betadine and draped.

Video 1
Include Video

Soft tissue Exposure

The four corners of the patella and the tibial tubercle we marked, and two horizontal lines, 3 finger breadths above and below the patella were drawn . The leg was exsanguinated with an Esmarch , and the tourniquet was inflated.

The knee was slightly flexed and a straight midline incision was made using 10- blade, coursing from 5cm proximal to the patella to 5 cm distal to it. The incision was taken through the subcutaneous tissues to the depth of the extensor mechanism beginning proximally.

Photo 2


The skin is marked, and the incision is make while the knee is flexed, from points approximately 3 finger-breadths above and below the patella.
A medial soft tissue sleeve was developed using a blade from mid-patella and swept up to expose the quadriceps tendon and then downward from mid-patella to the tubercle.

Photo 3

Use the posterior surface of the blade to identify the medial border of the retinaculum. Make one sweep superiorly and one inferiorly keeping the flap of subcutaneous tissue thick.
 
An arthrotomy incision was begun just medial to the tibial tubercle and advanced directly on bone, to the patella; and then proximally coursing 3 mm medial to the patella itself; and, finally, it coursed up the body of the quadriceps tendon in line with its fibers.

Photo 4
Arthrotomy of the joint is perfomed with sufficient tissue left along the medial border of the patella for closure. This is facilitated by placing the knife parallel to the posterior surface of the patella.


The bump was then moved from behind the knee to the ankle, placing the leg in full extension . The patella was retracted laterally, and a small amount of fat and synovium was removed from the distal femur .

The posterior (deep) surface of the patellar tendon was freed of any soft tissues adherent to the tibia.

The bovie was then used to elevate a subperiosteal flap around the proximal medial tibia. This flap was begun at the tibial plateau just medial to the patellar tendon, coursing distally for two centimeters.

Photo 5

The medial release is performed by elevating a sub-periosteal flap with a Bovie, starting just medial to the tibial tubercle and continued subperiosteolly in a medial direction. When you reach the anteromedial corner, switch to a Cobb elevator, which bluntly dissects the plane to reach the posterior medial corner of the tibia.

Once the flap was initiated, a Cobb elevator was placed under it and tapped into the space to release the posterior medial capsule, with care taken to protect the overlying medial collateral ligament. The patella was then gently everted and the knee flexed to 90 degrees . The fat pad was then excised .

Attention was then directed at removing the remnants of medial and lateral menisci. Then, beginning in the intercondylar notch, a 1/2 inch osteotome was utilized to remove the osteophytes obscuring the cruciate ligaments.

Photo 6

Osteotomes are used to open up the intercondylar notch by removing osteophytes allowing easy access to the cruciate ligaments.

The anterior and posterior cruciate ligaments were completely resected with a Bovie .

A blunt Homan retractor was then placed through the notch to rest posterior to the tibial plateau . The PCL attachment was released

Photo 7

Use a Bovie electrocautery to remove the PCL attachment off the posterior surface of the tibia.

NO SUCH PICTURE YET


and by levering the Homan, the tibia was subluxated anteriorly and gently externally rotated as well.

Photo 8

Gentle leverage on the blunt Homan retractor coupled with external rotation of the tibia will deliver the posterior-medial corner of the tibia forward, and allows for easy resection of the medial meniscus.


The now-exposed medial meniscus was then grabbed with a Kocher clamp and removed nearly in its entirety .

Attention was then directed toward the lateral joint where a Z-retractor was placed lateral to the meniscus along the lateral proximal tibia. The lateral meniscus was then removed.

Photo 9

Excision of the lateral meniscus, from anterior to posterior.


Attention was then directed toward making the bone cuts.

Tibial preparation

A left sided extramedullary cutting guide was placed on the tibial plateau with the drop bar parallel to the tibial shaft and aimed at the second metatarsal and secured to the tibia with three pins.

Photo 10

The extra-medullary guide is used to resect approximately 10 mm of tibia perpendicular to the shaft. JB: A BETTER PICTURE WOULD SHOW GUIDE IN PLACE PRIOR TO SAWING
 
The guide was positioned to remove 10 mm of bone from the lateral side .

An oscillating saw was used to make the tibial cut sloping posteriorly beginning on the lateral side.

The cutting block and resected bone was removed and the tibial sizing tray was secured with two pins. A medullary drill followed by punch was used to broach the tibial metaphysis .

Photo 11

After drilling, the tibial broach is impacted in appropriate position.

NO PICTURE OF THIS IN SLIDESHOW 

Femoral preparation

The knee was then flexed and a distal femoral retractor was then set on the cut superior surface of the tibia to place the flexion gap in tension and to verify aligment .

Photo 12

The distal femoral retractor is placed to protect the cut tibial surface and apply tension to the soft tissues. Thus the flexion gap can be accurately assessed. Further balancing may be performed here using lamina spreaders. JB: NOT THE RIGHT PICTURE. ONE DESCRIBED NOT IN SHOW

The Z-retractors were then placed at the margins of the joint and a Bovie used to mark Whiteside’s line .

A drill was used to begin the femoral canal which was widened with a T-handled reamer.

Photo 13

The T- handle reamer is placed retrograde into the distal femur to decompress the canal and confirm alignment.

A femoral component sizing guide was placed on the distal femur making sure that it was flush with the anterolateral cortex of the femur.

Photo 14

Proper sizing assessed with a guide

NO SUCH PICTURE IN SLIDE SHOW 
The sizing guide was replaced with the intra-medullary femoral alignment guide set at 5 degrees valgus.

Photo 15

An intramedullary cutting guide is placed in fixed 5 degrees of valgus.

The distal femoral bone cuts were made using the jig for guidance.

Photo 16

The use of a 5 in 1 cutting guide allows for efficient and reproducible bone cuts. Details for the particular cutting guides are available in monographs supplied by the various manufacturers.
 
A box cutting guide was placed and medial, lateral and superior box cuts were made with a reciprocating saw.

Photo 17

The cutting guide to remove bone for a posterior cruciate-substituting knee is placed completely flush with the femur and slightly lateral from the midline

Trial components were implanted and correct flexion and extension gap balancing was determined .

Photo 18

Observe correct balance in flexion and extension with the trials in place.
JB NOT PARTICULARLY ILLUSTRATIVE

Patellar preparation

A 10 mm wafer of cartilage and bone was cut from the patella starting at its “nose” leaving ~15 mm of bone .

Photo 19

The patellar cut is made on the everted patella beginning inferiorly on the ‘nose’ of the patella

After sizing, three eccentric drill holes were made in the patella to accommodate the polyethylene patellar implant.

Tracking was assessed with full flexion and extension range of motion testing using the “no thumbs” technique .

Photo 20

No thumbs tracking through full range of motion is crucial to success of the clinical result.

NO PICTURE OF THIS IN SLIDESHOW

Implanting and Cementing

The wound and bone surfaces were then copiously irrigated with saline and dried .

The cement was mixed and placed in the femoral canal, on the femoral condyles, and on the femoral component itself. The femoral component was impacted into place and all excess cement was removed.

A Homan retractor was placed behind the tibia, and cement was inserted into the tibial hole and on the tibial surface, leaving the edges without cement. The tibial component was appropriately rotated , impacted and all excess cement was removed.

Photo 21

After the femur is cemented and excess cement removed from around the component, a sponge is placed to protect the femoral component from the homan retractor. The homan retractor is then placed to gently lever the tibia forward to allow impaction of the tibial component in proper orientation.

NO PICTURE OF THIS IN SLIDESHOW 
The knee was held in full extension.

Photo 22

Use the patellar clamp to secure the patella while holding the knee in full extension and the foot dorsiflexed to compress the cement under pressure.

NO PICTURE OF THIS IN SLIDESHOW
Cement was placed into the three holes for the patellar insert, and the polyethylene component is secured and held in place with a patellar clamp . The knee was irrigated but not drained.

Closure

The prosthesis and the wounds were copiously irrigated.

A medium Hemovac drain was placed in the proximal patellar pouch.

A #1 figure of eight Ethibond stitch was used to suture the sides of the arthrotomy into apposition and a ‘drop test’ was performed to confirm full flexion.

Photo 23

After the retinaculum is closed, allow gravity to flex the knee fully. This maneuver will ensure that full post-operative flexion can be achieved.
 
An 0 Vicryl suture approximated Scarpa’s Fascia followed by 2-0 Vicryl for the subcutaneous tissue. Staples were used for the skin. A dressing was applied.

Photo 24

The finished product.

 

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