Please confirm topic selection

Are you sure you want to trigger topic in your Anconeus AI algorithm?

Please confirm action

You are done for today with this topic.

Would you like to start learning session with this topic items scheduled for future?

Osteochondral Plug Allograft Transfer of the Knee

Preoperative Patient Care
Operative Techniques
E

Preoperative Plan

1

Determine pathology using MRI

  • radial tear
  • horizontal cleavage tear
  • displaced bucket handle tear
  • meniscal root tear
  • discoid meniscus

2

Execute surgical walkthrough

  • describe steps of the procedure verbally to the attending prior to the start of the case
  • describe potential complications and steps to avoid them
F

Room Preparation

1

Surgical Instrumentation

  • standard arthroscopy pump
  • motorized meniscal shaver
  • toothed grasper
  • double loaded 2-0 or 0 nonabsorbable sutures with long flexible needles

2

Room setup and Equipment

  • standard OR table with leg holder

3

Patient Positioning

  • supine
  • leg holders
  • place leg holder 5 to 8 cm proximal to the superior pole of the patella to maximize control of the limb
  • contralateral leg is placed in a well leg holder
  • for the diagnostic portion of the procedure is placed at the foot of the bed
  • for the remainder of the procedure, the foot of the bed is dropped
G

Scope Insertion

1

Mark out the anatomy of the knee

  • draw out the patella, patellar tendon, medial and lateral joint lines and the posterior contours of the medial and lateral femoral condyles

2

Place anterolateral portal

  • use 22 gauge needle on syringe and bury the needle
  • make wheal at skin and then 11 blade in same direction as the needle
  • place scope in same direction as needle and blade
  • hug the patellar tendon

3

Place anteromedial portal

  • place knee in 30 degrees of flexion with valgus moment applied
  • use a spinal needle to assess direction and appropriate superior/inferior direction.
  • visualize with lateral portal
H

Diagnostic Arthroscopy

1

Visualize

  • suprapatellar pouch
  • patellofemoral joint (take picture)
  • place bump under heel prn
  • lateral gutter
  • look for loose bodies and peripheral tears of LM
  • get MFC in view
  • bring knee into slight flexion and valgus as you go into medial compartment.
  • foot goes on to opposite hip and use standee to stabilize your foot
  • medial meniscus (take picture)
  • drop leg to flexion (bump should be under knee)

2

Establish far anteromedial portal

  • use 18-gauge needle to make sure that you clear the MFC and can get to the 2 o’clock (LEFT) or 10 o’clock (RIGHT) knee

3

Visualize

  • medial compartment - probe medial meniscus, articular cartilage
  • intercondylar notch – ACL/PCL (take picture)
  • lateral compartment – probe lateral meniscus, articular cartilage (take picture)
  • assess the full thickness articular lesion
I

Lesion Evaluation and Preparation

1

Plan the best perpendicular approach

  • place a 16 gauge needle to plan the best perpendicular approach to both the defect and the donor sites

2

Prepare the defect

  • prepare the defect by removing loose debris
  • freshen the edges with a curette or an arthroscopic nife to create perpendicular chondral walls
  • clear the subchondral bone of any residual articular cartilage
  • avoid generalized bone bleeding
J

Determining the Number of Grafts

1

Measure the defect size and shape

  • use a probe to obtain a preliminary measurement of the defects shape and dimensions

2

Determine the number of grafts needed to fill the defect

  • when more than one graft is used, maintain a 2-3 mm bone bridge between the recipient sites to ensure a good press fit

3

Measure depths of the lesions

  • measure the depths of the lesion using a 2 mm mark on the harvester
  • 6 mm grafts hav been shown to fill the diameter of the defects the best
  • larger plug harvesters are available but may require an arthrotomy and are more likely to encroach on weightbearing areas at harvest sites

4

Place grafts in the appropriate order

  • place the grafts starting at the periphery of the defect so that the articular cartilage matches the adjacent chondral edge after transplantation

5

Measure the depth of the lesions

  • analyze the depth of the defect
  • in most cases a standard 10.5-12 mm harvester is sufficient
  • osteochondral lesions or lesions with significant bone loss may require the use of variable depth harvester and placement of grafts that have cancellous sections standing above the crater base
K

Defect Preparation

1

Debride the subchondral bone

  • remove any residual articular cartilage from the subchondral bone

2

Drill the recipient site

  • drill the recipient site before harvesting the donor autograft plugs
  • this allows the selection of the best match on the femoral surface between the donor grafts and the articular cartilage adjacent to the recipient sites
  • using the COR perpendicularity system reproducibly identifies the best orientation for drilling the recipient site
  • this also makes it feasible to drill the recipient site before harvesting the grafts

3

Insert the drill guide

  • insert the drill guide with the perpendicularity rod through the portal and into position at the recipient site

4

Disengage the drill guide

  • with the drill guide positioned in a perpendicular orientation, turn the perpendicularity rod counterclockwise until it disengages
  • remove the rod

5

Drill the recipient sites

  • drill the recipient sites with the corresponding COR drill bit under direct arthroscopi visualization
  • keep the drill perpendicular to the articular surface
  • the projecting tooth at the drill keeps the drill from walking
  • this allows precise recipient site placement by creating a starter hole

6

Drill to the appropriate depth

  • advance the drill to the appropriate depth using the markings 5 mm, 8mm,10 mm, 12 mm and 15 mm and 20 mm that is found on the side of the drill
  • compare this line to the adjacent articular cartilage
  • the fluted drills concave sides remove bone during drilling and reduce both friction and heat
  • in the cases of subchondral bone loss the depth should be used and the depth underdrilled to restore the contour and height of the articular surface
  • this is done by aligning the laser mark with the desired articular cartilage height
  • the recipient holes can be drilled at the same time or sequentially after autograft insertion

7

Maintain the bony bridge

  • care should be taken to maintain a bone bridge between the recipient sites 2 to 3 mm and avoid recipient site convergence

8

Insert the harvester into the disposable cutter

9

Remove the retropatellar fat pad

  • completely debride the retropatellar fat pad to improve visualization and to avoid soft tissue entrapment

10

Insert the perpendicularity rod

  • insert the perpendicularity rod into the harvest cutter assembly before the insertion into the joint
  • the perpendicularity rod will function as an obturator and minimize both soft tissue capture and fluid loss as the assembly is inserted into the knee

11

Prepare the graft harvest

  • position the harvester delivery guide/cutter/perpendicularity rod assembly on the donor site in preparation of the graft harvest
  • use the perpendicularity rod to confirm the perpendicular position of the cutter and then remove
  • rotate the arthroscope to confirm alignment from many angles

12

Cut to the desired depth

  • use a mallet to tap the harvester delivery guide/cutter to the desired depth

13

Remove the plug

  • remove the plug by gently twisting the T-Handle while withdrawing the plug
  • avoid toggling the donot hole

14

Place the harvest delivery system

  • insert the harvester delivery guide system/cutter into the graft loader
  • push down firmly until it makes contact with the bottom of the loader
  • push the harvest graft from the cancellous bone side of the graft plug upwards into the harvester/delivery system guide and out of the cutter section

15

Remove the harvester from the cutter

  • the graft plug will remain inside the harvester until it is transplanted
L

Graft Insertion and Backfilling

1

Disassemble the harvester tube from the cutter

2

Place the harvester tube in the clear plastic insertion tube with depth markings

  • place the plastic plunger in the harvester delivery system before insertion of the delivery into the joint

3

Place in the knee

  • insert the loaded harvester-clear plastic delivery guide system into the knee
  • the portal may need to be enlarged for passage of the delivery guide system
  • place the clear end of the delivery system with the graft tip slightly projecting perpendicularly at the recipient site outlet

4

Position the autograft

  • align the articular cartilage of the autograft with the adjacent articular cartilage
  • implant with gentle tapping until it is flush with the articular cartilage
  • the 8mm side is recommended for 4 mm and 6 mm grafts
  • the 12 mm side is recommended for 8 mm and 10 mm grafts
  • use a universal tamp to fine tune the graft placement

5

Fill the donor sites

  • especially for harvested plugs greater than 6 mm in diameter or if multiple plugs have been harvested from a single area
  • larger diameter and deep defects can cause excessive stress on the surrounding cartilage and degeneration
N

Wound Closure

1

Use 3-0 and 4-0 biosyn for closure

  • apply steristrips

2

Cover with tegaderm and occlusive dressings

Postoperative Patient Care
Private Note

Attach Treatment Poll
Treatment poll is required to gain more useful feedback from members.
Please enter Question Text
Please enter at least 2 unique options
Please enter at least 2 unique options
Please enter at least 2 unique options