Figure 2: Area of actual debridement

Figure 3: Area following debridement

Figure 4: MFC Defect after debridement

4. The base of the defect is gently debrided of fibrous tissue. The calcified cartilage layer should be exposedm however, the subchondral plate must not be violated. Ideally, the defect base is lightly debrided to allow a pinkish hue appearance without causing any bleeding.

Figure 5: MFC defect with fibrinous debris present

Figure 6: MFC defect following debridement. Tourniquet deflated.

5. Following debridement, the size of the defect is measured. At this point, a template is cut. Be sure to oversize the template by 2 mm in all directions. Usually, a piece of sterile paper (such as from the surgical glove wrapper) is obtained. A skin marker is used to mark the size of the defect on the paper. The paper template may be marked in several different ways:

Figure 7: Defect measurement

a. A simple rectangle may be cut using the length and width of the widest portions of the defect. Later the excess periosteal tissue may be trimmed to allow matching of the patch to the actual defect.

b. A template may be fashioned that more approximates the actual shape of the defect. In this case, later trimming of the patch is not necessary. However, if the harvested patch is not perfectly matched to the defect, it will be difficult to compensate for any discrepancies.

Figure 8: Template used for case in fig.6

6. At this point, the defect is packed with epinephrine soaked neuro sponges. Alternatively, thrombin (5000 Units), or thrombin spray, or a Bovie tip turned to 5-8 watts may be used on the point of bleeding at the base of the defect. Ideally, the defect base needs to be dry and without any bleeding points. The knee is brought to full extension and attention directed to the periosteal patch harvesting.

7. A longitudinal second incision is made at the medial aspect of the tibial crest. Dissection allows identification of the anteromedial tibial border, which is the donor site. Using a damp sponge, the overlaying fat and fibrous tissue is gently swept from the site of the proposed graft. The periosteal tissue should not be violated. Aggressive soft tissue debridement is contraindicated.

Figure 9: Recommended incision site for periosteal harvesting

8. At this point the previously prepared template is place in the depths of the incision, overlaying the anteromedial tibial periosteum. The extent of the harvested tissue is marked and the template is removed from the wound. The outer layer of the proposed periosteal patch is marked with a blue dot to allow later identification of the outer layer and the cambium layer of the patch.

Be aware of the fact that as a person's age increases, the periosteum becomes progressively thinner and more susceptible to accidental tearing.

9. Using a sharp periosteal elevator, the periosteum is gently elevated from the anteromedial tibial border as previously marked. The elevation of this tissue requires meticulous dissection. The tissue layer must be intact and be as large as the template. The further distal that one goes on the tibia, the less satisfactory the periosteal tissue is, as it becomes increasingly thin. The more proximal that one goes on the tibia, the more difficult it is to obtain only a layer of periosteal tissue. The expansions of the pes tendon insertion begin to blend with the periosteum making the harvested periosteal patch too thick.

When using the rectangular template method, a #15 blade should be used to score the anterior, posterior and distal margins of the proposed periosteal patch. Using the periosteal elevator, elevation of the patch is started distally and progresses proximally. By harvesting in this distal to proximal fashion, if the patch tears distally, then extending the harvesting in a proximal direction will still allow an intact periosteal patch to be harvested. This alleviates the need to oversew or repair a torn periosteal patch. By beginning the harvesting distally, where the periosteum is structurally the thinnest, if a tear occurs, the proximal margins may be extended. However, if the harvesting begins proximally and extends distally, then any tear in the structurally thin distal aspect of the periosteal patch will require repair prior to implantation.

10. Once harvested, the patch should be placed on a plastic skin graft transport carrier. This allows the periosteal graft to be handle minimally. It needs to be covered with a damp sponge to prevent drying out. The patch is placed on the carrier with the cambium side up. (The previously placed skin maker dot should be face down.)

11. At this point, attention is redirected towards the knee joint. The tourniquet is deflated, soft tissue hemostasis is obtained, and the neuro sponges are removed from the defect. The bed of the defect should be dry. If this is not the case, thrombin (5000 Units), or thrombin spray, or a Bovie tip turned to 5-8 watts may be used on the point of bleeding at the base of the defect. Ideally, the defect base needs to be dry and without any bleeding points.

12. At this point, the plastic carrier with the periosteal graft is trimmed to the same size as the graft. The carrier with the graft may then be placed over the defect to determine the amount of trimming that needs to be done. If necessary, the graft and carrier may be trimmed and the excess periosteal patch removed. The carrier is then placed over the defect, and the patch gently peeled from the carrier and placed on the defect. (This process is similar to placing a meshed split thickness skin graft in place.) The carrier is then carefully removed.

13. Ideally, the periosteal patch fits into the defect without overlapping the edges of the defect. The graft is sewn in place by using 6-0 vicryl suture on a P-1 cutting needle. Prior to the passage of each suture line, the suture should be lubricated with mineral oil. Shortening the suture to approximately 12 inches facilitates passage of the suture. The technique for graft sewing is very specific.

a. Using forceps without teeth (so that the periosteal patch is not punctured), the needle enters that graft and then enters the adjacent articular cartilage. The entrance of the needle is into the periosteal patch is approximately 3-5 mm from the margin of the patch. The needle should enter the articular cartilage wall approximately 2 mm below the articular surface. The exit of the needle from the articular cartilage is approximately 3-5 mm from the margin of the defect. The sutures are spaced approximately 3-4 mm apart (Figure 12).



Figure 10: Notice suture needle placement, direction of suturing, and depth of bite in the adjacent articular cartilage

b. Gently holding the patch in place, the suture is gently pulled through the graft and the articular cartilage. It is necessary to pull the suture through the articular cartilage and the periosteal patch in line with the suture track so that the suture does not pull through the articular cartilage or tear the periosteal graft.



Figure 11: Suturing of patch.

c. Once the suture has been pulled through, the suture is tied with the knot manipulated so that it is lying on top of the periosteal patch. It should not be on top of the articular cartilage.

Figure 12: Notice suture knot placement on the periosteal patch

Figure 13: Patch after being sewn into place.

d. Although individual circumstances may require different suturing techniques, normally, placement of the sutures at diagonals from each other allows for proper tensioning of the graft during suture attachment.

e. In general, it is usually easier to do the suturing if the suture is trimmed to a length of about 12 inches and coated with mineral oil after each suture pass. Be sure to use smooth tipped forceps. Begin suturing in the most difficult corner of the defect initially. Be sure to leave a superior opening for later saline injection.

f. Suturing is continued in this fashion in a circular fashion around the graft until the graft is satisfactorily attached.

Figure 14: Sewn patch

14. Once suturing has been completed, testing for watertight integrity is performed. This is done by using a TB syringe, which has been filled with sterile saline and is attached to a 21 gauge IV plastic catheter. The blunt tipped catheter is carefully inserted through the remaining opening at the top of the periosteal patch. The catheter is advanced to the bottom of the defect and the saline is gently injected. Careful observation is done to determine if there are any areas of saline leakage around the periosteal patch. The areas of leakage are carefully closed with additional suture and the leakage test is repeated. Be careful not to overdistend the patch and artificially create areas of leakage or rents in the patch. Once watertight integrity has been obtained. The catheter is gently reintroduced into the defect, and advanced to the bottom of the defect. In this position, the saline is then aspirated from beneath the patch.

Figure 15: Testing for watertight integrity.

Figure 16: Injection of saline for watertight integrity.

15. The fibrin sealant is now applied. It may be prepared from autologous blood previously donated, or Tisseel sealant may be used. Following the appropriate preparations, the sealant is carefully applied to the suture line. As the sealant is applied, it will form a sticky substance and adhere to the suture line. Be sure to leave the superior opening (for injection) unsealed.

If autologous blood is donated, it is essential that a double spin-down be performed to obtain a supernatant "slush" of fibrinogen. Red Cross blood banks do this as a standard operating procedure.

Figure 17: Application of fibrin sealant at margins of patch.

16. Moving to a separate sterile Mayo stand, the Carticel graft is prepared. The container containing the graft is not sterile. After wiping the seal of the container, a TB syringe with the supplied needle is gently advanced into the Carticel preparation. Ideally a luer lock syringe is used to prevent inadverdent separation of the needle from the syringe with loss of the suspended cells.

Figure 18: Carticel preparation.

The Carticel preparation has two layers of material. The cells have settled into the bottom of the container while the fluid has collected in a fluid layer above the cells. It is necessary to mix these two layers. This is done by:

a. Advancing the needle into the supernatant fluid layer and gently withdrawing the fluid into the syringe. Once the fluid has been removed, the needle is advanced into the container and advanced to the bottom of the container. Once here, the aspirated supernatant is gently injected into the container. This allows for the gradual mixing of the cells with the fluid. After injecting the fluid, the container is again aspirated and gently reinjected to allow for further mixing. This process is repeated several times. Finally, the fluid and cells are again withdrawn into the TB syringe.



Figure 19: Mixing of cells and supernatant fluid



Figure 20: Mixing of cells and supernatant fluid

b. At this point, the catheter and the syringe should be held at their junction to prevent separation and subsequent loss of the Carticel cells. The nonsterile Carticel container is removed. Always keep the syringe in the upright position (with the tip pointing down). The surgical team may elect to change gloves on a PRN basis.

17. The Carticel graft is then gently injected under the periosteal patch using a 2 inch 18 gauge blunt tipped angiocath.

Figure 21: Injecting Carticel under periosteal patch.

18. Once injected, the superior opening is gently sewn closed and sealed with the fibrin sealant or Tisseel. Alternatively, prior to injection of the Carticel implant, the surgeon may elect to place the closing suture, but leave the suture loose and untied until following Carticel injection.

Figure 22: Completed graft

19. Following completion of this part of the procedure, the arthrotomy and accessory incisions are closed in the standard fashion.

20. Postoperatively, a knee immobilizer is applied and the appropriate post op Carticel rehab protocol is followed.

21. Drain usage is at the option of the surgeon. However, the drain must NOT be placed in an intra-articular position.

For Additional Information on Carticel Rehabilitation Procedures: PHYSICAL THERAPY PROTOCOLS

For a REALAUDIO/VIDEO presentation of the Carticel Surgical Procedure: CARTICEL SURGICAL PROCEDURE

EMAIL THIS SITE TO A FRIEND

Questions, Comments or Tips on ACI/Knee Injuries: Post Them at: Orthopedic & Arthroscopic Message Board

THIS MATERIAL DOES NOT CONSTITUTE MEDICAL ADVICE. IT IS INTENDED FOR INFORMATIONAL PURPOSES ONLY. PLEASE CONSULT A PHYSICIAN FOR SPECIFIC TREATMENT RECOMMENDATIONS.

THE CENTER FOR ORTHOPAEDICS AND SPORTS MEDICINE
1211 JOHNSON FERRY RD.; MARIETTA, GA., 30068
770-565-0011
http://www.arthroscopy.com

Last Update: 04/03/2003
Copyright ©1999 by The Center for Orthopaedics & Sports Medicine - ALL RIGHTS RESERVED