• Biopsy tools: arthroscopic-ready small gouge and/or small ring curette

• Biopsy medium and containers

• Shipping specimen process or storage arrangements

• The setup is identical to that used for routine arthroscopy.

• The patient is placed supine on the operating table.

• Maximal knee flexion should be possible.

• A tourniquet should be available but is not routinely used.

• Biopsy is harvested from lesser or non-weight bearing, nonarticulating surfaces.

• Superior lateral cartilage margin of lateral femoral condyle

• Superior medial cartilage margin of medial femoral condyle

• Intercondylar trochlear notch

• A ring curette or curved notchplasty gouge is used.

• Cartilage biopsy is “peeled off” with the harvest tool and is left attached on one edge.

• A grasper is used to break away the remaining attachment of the cartilage biopsy (prevents specimen from becoming a loose body).

• Two to three slivers of full-thickness normal appearing cartilage tissue (measuring 4 to 5 mm × 7 to 9 mm) are removed down to subchondral bone.

• The approximate weight of specimen is 200 to 300 g.

• The biopsy specimen is placed in sterile medium, and the container is properly marked with all appropriate patient information.

• With ex vivo culture, a 12-fold increase in total autologous chondrocytes takes about 3 to 4 weeks, although culture can be cryopreserved to allow optimal patient timing for reimplantation.

• Cultured chondrocytes (delivery arranged and verified)

• Fibrin glue preparation

• Specialty absorbable sutures (6-0 Vicryl)

• Small curettes

• Fine instrument needle holder, scissors, nontoothed pickups

• Absorbable type I/III collagen membrane, sterile packaged, 50 × 40 mm

• Available micro-absorbable anchors that can be reloaded with absorbable 5-0 Vicryl sutures

• Standard supine positioning for knee arthrotomy.

• Maximal knee flexion should be possible.

• A tourniquet should be available; it is used only during exposure and defect debridement and then is let down (<60 minutes at lowest pressure possible).

• Depends on defect location

• Influenced by any concomitant procedures

• Adequate exposure is vital for any successful cartilage repair; however, the degree of exposure varies by defect location, size, and chondrocyte implantation technique.

• Medial or lateral parapatellar incision and arthrotomy can be used.

• An incision is created that could be extended and reused for future procedures such as total knee arthroplasty.

• The patella is everted for more posterior condyle lesions or multiple lesions.

• For patellofemoral lesions, the tubercle can be detached as part of a concomitant realignment procedure and reflected proximally by cutting the fat pad just anterior to the transverse intermeniscal ligament and performing lateral retinacular lengthening and medial capsular incision superiorly up to the vastus medialis obliquus (VMO) without violating its insertion.

• Fibrous tissue and damaged chondral tissue are removed with small curettes down to the level of subchondral bone (Fig. 60-1).

• Once exposure is obtained, the defect is demarcated by scoring the periphery of the defect with a no. 15 blade.

• This creates a delineation between damaged, injured cartilage, and healthier surrounding cartilage tissue.

• The cut should be to bone level and should create a distinct 90-degree wall at the defect margin (Fig. 60-2).

• Small curettes are used to debride the defect to remove the calcified cartilage, fibrocartilage, and damaged cartilage.

• Penetration or damage to the subchondral bone should be avoided.

• Because blood may dilute the concentration of chondrocytes, any bleeding from the base of the defect needs to be controlled.

• Thrombin spray and/or epinephrine soaked neuropatty sponges with pressure

• Gelfoam hemostatic sponge and fibrin glue

• Electrocautery with needle point and low voltage

• The goal of this preparation is to have a dry bed of clean subchondral bone and a firm healthyappearing, sharply demarcated, surrounding cartilage border at the periphery.