The knee.

Mark Clathworthy, Patrick Djian, Bjorn Engstrom, Bent Wulff Jakobsen

Contents

Position of the patientStandard portals

anatomy

Additional portalsRoutine travel through knee

Supra patellar pouchPatello femoral jointMedial gutterMedial compartmentIntercondylar notchLateral compartmentLateral gutterPosterior cavity

Variation of normalmediale plicaanterior plica

Take home message

Positioning of the patient

Supine

Draped

Lat support

Prepared

Tourniquet and irrigation

Pressure tourniquet 280-350 mmHg

Irrigation options:Arthroscopic pump

Gravity

Pressure saline bags

Standard portals

Courtesy to Pao Golano

Antero-lateral (1)the a-l portal is used as the standard viewing portal, through which you can access most of the joint

Antero-medial (2)the a-m portal is used as the standard working portal through which you can probe the majority of the joint

Superior-lateral (3)The s-l portal is used for optional outflow cannula and for probing the suprapatellar cavity

Posterior-medial (4)The p-m portal is used accessing the posterior cavity

2

Antero-lateral (1)the a-l portal is used as the standard viewing portal, through which you can access most of the joint

Antero-medial (2)the a-m portal is used as the standard working portal through which you can probe the majority of the joint

Superior-lateral (3)The s-l portal is used for optional outflow cannula and for probing the suprapatellar cavity

Posterior-medial (4)The p-m portal is used accessing the posterior cavity

1

3

Antero-lateral (1)the a-l portal is used as the standard viewing portal, through which you can access most of the joint

Antero-medial (2)the a-m portal is used as the standard working portal through which you can probe the majority of the joint

Superior-lateral (3)The s-l portal is used for optional outflow cannula and for probing the suprapatellar cavity

Posterior-medial (4)The p-m portal is used accessing the posterior cavity

2

4

Antero-lateral (1)the a-l portal is used as the standard viewing portal, through which you can access most of the joint

Antero-medial (2)the a-m portal is used as the standard working portal through which you can probe the majority of the joint

Superior-lateral (3)The s-l portal is used for optional outflow cannula and for probing the suprapatellar cavity

Posterior-medial (4)The p-m portal is used accessing the posterior cavity

Courtesy to Pao Golano

Anatomy

The subcutaneous nerve around the knee of importance related to the arthroscopic portals is the infrapatellar branch of the saphenus nerve.

The antero-medial portal is closely related to the branch.

The antero-lateral portal is only related to subcutaneous nerve branches in cases of abnormal anatomical arrangement.

The postero-medial portal is placed immediately proximal to the hamstring tendons thereby avoiding the nerve branch of the saphenus nerve and the vessels.

The subcutaneous nerve around the knee of importance related to the arthroscopic portals is the infrapatellar branch of the saphenus nerve.

The antero-medial portal is closely related to the branch.

The antero-lateral portal is only related to subcutaneous nerve branches in cases of abnormal anatomical arrangement.

The postero-medial portal is placed immediately proximal to the hamstring tendons thereby avoiding the nerve branch of the saphenus nerve and the vessels.

The subcutaneous nerve around the knee of importance related to the arthroscopic portals is the infrapatellar branch of the saphenus nerve.

The antero-medial portal is closely related to the branch.

The antero-lateral portal is only related to subcutaneous nerve branches in cases of abnormal anatomical arrangement.

The postero-medial portal is placed immediately proximal to the hamstring tendons thereby avoiding the nerve branch of the saphenus nerve and the vessels.

The subcutaneous nerve around the knee of importance related to the arthroscopic portals is the infrapatellar branch of the saphenus nerve.

The antero-medial portal is closely related to the branch.

The antero-lateral portal is only related to subcutaneous nerve branches in cases of abnormal anatomical arrangement.

The postero-medial portal is placed immediately proximal to the hamstring tendons thereby avoiding the nerve branch of the saphenus nerve and the vessels.

Additional portals

Courtesy to Pao Golano

Middle patella medial (5)Additional portal convenient for viewing anterior of medial meniscus

Middle patella lateral (6)Additional portal convenient for viewing anterior horn of lateral meniscus

Postero-lateral (7)Additional portal convenient for viewing and exploring postero-lateral compartment

Middle patella medial (5)Additional portal convenient for viewing anterior of medial meniscus

Middle patella lateral (6)Additional portal convenient for viewing anterior horn of lateral meniscus

Postero-lateral (7)Additional portal convenient for viewing and exploring postero-lateral compartment

Middle patella medial (5)Additional portal convenient for viewing anterior of medial meniscus

Middle patella lateral (6)Additional portal convenient for viewing anterior horn of lateral meniscus

Postero-lateral (7)Additional portal convenient for viewing and exploring postero-lateral compartment

56

7

Left knee

Routine knee arthroscopy

1. Insert the blunt trocar through the antero-lateral portal to the patello femoral pouch. Attach 30° arthroscope and look through suprapatellar pouch by rotating the scope 180° back and forward and scan the area.

2. Pull back gently scope overlooking patellofemoral joint on the extended knee from lateral and from medial side. If you drain the joint you can examine the patellofemoral joint stability better.

3. Reopen water supply and return to suprapatellar pouch. Follow capsular fold medial through the medial gutter to overlook the synovium and the medial femoral condyle.

4. Note the anterior horn of the med meniscus and apply a gentle valgus load on the lower leg to open medial compartment. Mark externally the spot for the medial portal with finger on skin or with a needle.

Routine travel

1

3

2

46

8

7

95

1. Insert the blunt trocar through the antero-lateral portal to the patello femoral pouch. Attach 30° arthroscope and look through suprapatellar pouch by rotating the scope 180° back and forward and scan the area.

2. Pull back gently scope overlooking patellofemoral joint on the extended knee from lateral and from medial side. If you drain the joint you can examine the patellofemoral joint stability better..

3. Reopen water supply and return to suprapatellar pouch. Follow capsular fold medial through the medial gutter to overlook the synovium and the medial femoral condyle.

4. Note the anterior horn of the med meniscus and apply a gentle valgus load on the lower leg to open medial compartment. Mark externally the spot for the medial portal with finger on skin or with a needle.

1. Insert the blunt trocar through the antero-lateral to the patello femoral pouch. Attach 30° arthroscope and look through suprapatellar pouch by rotating the scope 180° back and forward and scan the area.

2. Pull back gently scope overlooking patellofemoral joint on the extended knee from lateral and from medial side. If you drain the joint you can examine the patellofemoral joint stability better.

3. Reopen water supply and return to suprapatellar pouch. Follow capsular fold medial through the medial gutter to overlook the synovium and the medial femoral condyle.

4. Note the anterior horn of the med meniscus and apply a gentle valgus load on the lower leg to open medial compartment. Mark externally the spot for the medial portal with finger on skin or with a needle.

1. Insert the blunt trocar through the antero-lateral portal to the patello femoral pouch. Attach 30° arthroscope and look through suprapatellar pouch by rotating the scope 180° back and forward and scan the area.

2. Pull back gently scope overlooking patellofemoral joint on the extended knee from lateral and from medial side. If you drain the joint you can examine the patellofemoral joint stability better.

3. Reopen water supply and return to suprapatellar pouch. Follow capsular fold medial through the medial gutter to overlook the synovium and the medial femoral condyle.

4. Note the anterior horn of the med meniscus and apply a gentle valgus load on the lower leg to open medial compartment. Mark externally the spot for the medial portal with finger on skin or with a needle.

10

1. Insert the blunt trocar through the antero-lateral portal to the patello femoral pouch. Attach 30° arthroscope and look through suprapatellar pouch by rotating the scope 180° back and forward and scan the area.

2. Pull back gently scope overlooking patellofemoral joint on the extended knee from lateral and from medial side. If you drain the joint you can examine the patellofemoral joint stability better.

3. Reopen water supply and return to suprapatellar pouch. Follow capsular fold medial through the medial gutter to overlook the synovium and the medial femoral condyle.

4. Note the anterior horn of the med meniscus and apply a gentle valgus load on the lower leg to open medial compartment. Mark externally the spot for the medial portal with finger on skin or with a needle.

5. Rotate the scope looking centrally while flexing the knee to 90° examining the anterior cruciate from distally to proximally carefully probing the femoral attachment site. Next rotate the scope more medial to check the posterior cruciate often covered with synovium.

6. Rotate the scope looking laterally while applying a light varus stress to the slightly flexed knee – thereby overlooking and probing anterior horn of the lateral meniscus. Go to the ”figure of 4” position while keeping the scope parallel to tibial surface overlooking the middle third and posterior horn of meniscus.

7. Extend the knee and go directly to the lateral gutter, flex the knee and examíne the popliteus tendon and hiatus.

Routine travel

1

3

2

46

8

7

95

10

5. Rotate the scope looking centrally while flexing the knee to 90° examining the anterior cruciate from distally to proximally carefully probing the femoral attachment site. Next rotate the scope more medial to check the posterior cruciate often covered with synovium.

6. Rotate the scope looking laterally while applying a light varus stress to the slightly flexed knee – thereby overlooking and probing anterior horn of the lateral meniscus. Go to the ”figure of 4” position while keeping the scope parallel to tibial surface overlooking the middle third and posterior horn of meniscus.

7. Extend the knee and go directly to the lateral gutter, flex the knee and examíne the popliteus tendon and hiatus.

5. Rotate the scope looking centrally while flexing the knee to 90° examining the anterior cruciate from distally to proximally carefully probing the femoral attachment site. Next rotate the scope more medial to check the posterior cruciate often covered with synovium.

6. Rotate the scope looking laterally while applying a light varus stress to the slightly flexed knee – thereby overlooking and probing anterior horn of the lateral meniscus. Go to the ”figure of 4” position while keeping the scope parallel to tibial surface overlooking the middle third and posterior horn of meniscus.

7. Extend the knee and go directly to the lateral gutter, flex the knee and examíne the popliteus tendon and hiatus.

8. Return to the ”figure of 4” position guiding the movement with the scope centrally in the notch looking laterally. Rotate the scope while probing the lateral meniscus. Note popliteus tendon above and below the meniscus runnning though the popliteus hole.

9. While in the ”figure of 4” position mark the triangular shape given from lateral femoral condyle, tibial plateau and anterior cruciate. Looking parallel to the tibial plateau pass gentle the scope through the triangle to the posterior cavity. Check posterior horn of lateral meniscus, posterior cavity by rotating the the scope 360°. Retract the scope while overlooking the posterior cruciate and the proximal part of the anterior cruciate.

Routine travel

1

3

2

46

8

95

8. Return to the ”figure of 4” position guiding the movement with the scope centrally in the notch looking laterally. Rotate the scope while probing the lateral meniscus. Note popliteus tendon above and below the meniscus runnning though the popliteus hole.

9. While in the ”figure of 4” position mark the triangular shape given from lateral femoral condyle, tibial plateau and anterior cruciate. Looking parallel to the tibial plateau pass gentle the scope through the triangle to the posterior cavity. Check posterior horn of lateral meniscus, posterior cavity by rotating the the scope 360°. Retract the scope while overlooking the posterior cruciate and the proximal part of the anterior cruciate.

7

10

Routine travel

1

3

2

46

8

95

7

10

10. Put the knee 90 degrees of flexion. There will then be a triangle given from the medial femoral condyle, tibialplateau and the anterior cruciate ligament. Looking parallel to the tibial plateau pass gently the scope through the triangle to the posterior cavity. Sometimes you need to push the cruciate ligaments laterally and rotate the scope smoothly to pass this area. Check the posterior horn of the medial meniscus, posterior cavity by rotating the scope 360 degrees. Retract the scope while overlooking the posterior cruciate.

Supra patellar pouch

Superior view of supra patellar pouch; 30° arthroscope

32

46

87

9

1

510

Supra patellar pouch

Superior view of supra patellar pouch; 30° arthroscope

32

46

87

9

1

5

Vastus lateralis of the quadriceps muscle

10

Patello femoral joint

Femoral condyle lateral

Femoral condyle lateral view; 30° arthroscope

32

46

87

9

1

510

Patello femoral joint

Femoral trochlea

Femoral trochlea lateral view; 30° arthroscope

Patello femoral joint

32

46

87

9

1

510

Patello femoral joint

Femoral trochlea

Patello femoral joint proximal lateral view; 30° arthroscope

Patella

32

46

87

9

1

510

Medial gutter

Medial view of medial gutter; 30° arthroscope

Medial femoral condyle

Gutter

Patella

32

46

87

9

1

510

Medial gutter

Medial distal view of medial gutter; 30° arthroscope

Medial fem

oral condyle

Gutter3

246

87

9

1

510

Medial compartment

Distal view of medial meniscus anterior horn, knife producing a-m portal; 30° arthroscope

Medial femora

l condyle

Tibial plateau

Medial meniscus

32

46

87

9

1

5

Knife in a-m portal

10

Medial compartment

Distal view of medial meniscus anterior horn, probe through ant-med portal; 30° arthroscope

Medial femoral condyle

Tibial plateauM

edial meniscus

32

46

87

9

1

510

Medial compartment

Antero medial view of medial meniscus anterior horn underside, probe through ant-med portal; 30° arthroscope

Medial femoral condyle

Tibial plateau

Medial meniscus,

undersurface

32

46

87

9

1

510

Medial compartment

Medial view of medial meniscus central third; 30° arthroscope

Medial femoral condyle

Tibial plateau

Medial meniscus

32

46

87

9

1

510

Medial compartment

Medial view of medial meniscus central third, probe through anteromedial portal; 30° arthroscope

Medial femoral condyle

Tibial plateau

Medial meniscus

32

46

87

9

1

510

Medial compartment

Posteromedial view of medial meniscus posterior horn; 30° arthroscope

Medial femoral condyle

Tibial plateau

Medial meniscus

32

46

87

9

1

510

Medial compartment

Posteromedial view of medial meniscus posterior horn, tested with a probe; 30° arthroscope,

Medial femoral condyle

Tibial plateau

Medial m

eniscus

32

46

87

9

1

510

Medial compartment

Inferomedial view of anterior part of joint, femoral condyles, trochlea and Hoffa’s fat; 30° arthroscope

Medial femoral condyle

32

46

87

9

1

510

Intercondylar notch

32

46

87

9

1

5

Lateral femoral c

ondyle

Anterior cruciate

Inferior view of distal tibial attachment of anterior cruciate ligament, knee near extension; 30° arthroscope

10

Intercondylar notch

32

46

87

9

1

5

Late

ral f

emor

al c

ondy

le

Anterior cruciate

Posterior cruciate

Postero-central view of distal tibial attachment of anterior cruciate ligament, knee flexed 80°; 30° arthroscope

10

Intercondylar notch

32

46

87

9

1

5

Late

ral f

emor

al c

ondy

le

Anterior cruciate

Postero-central view of proximal femoral attachment of anterior cruciate ligament; 30° arthroscope

10

Intercondylar notch

32

46

87

9

1

5

Postero-central view of posterior cruciate, knee flexed 80°, PCL covered with synovium; 30° arthroscope

Anterior cruciate

Posterior cruciate

10

Intercondylar notch

32

46

87

9

1

5

Postero-central view of posterior cruciate, knee flexed 80°, PCL release from synovium; 30° arthroscope

Anterior cruciate

Poste

rior c

rucia

te

Med

ial f

emor

al c

ondy

le

10

Lateral compartment

32

46

87

9

1

5

Lateral meniscus

Anterior view of lateral meniscus anterior horn; 30° arthroscope

10

Lateral compartment

32

46

87

9

1

5

Lateral femoral condyle

Popliteustendon

Lateral meniscus

Antero-lateral view of lateral meniscus; 30° arthroscope

10

Lateral compartment

32

46

87

9

1

5

Lateral femoral condyle

Lateral meniscus

Antero-lateral view of lateral femoral condyle; 30° arthroscope

10

Lateral compartment

32

46

87

9

1

5

Lateral femoral condyle

Popliteus tendon

Lateral m

eniscus

Postero-lateral view of posterior horn of lateral meniscus and popliteus hole; 30° arthroscope

10

Lateral gutter

32

46

87

9

1

5

Lateral view on lateral gutter; 30° arthroscope

Late

ral g

utte

r

10

Lateral gutter

32

46

87

9

1

5

Lateral view on lateral gutter; 30° arthroscope

Late

ral f

emor

al c

ondy

le

Poplite

us te

ndon

Late

ral m

enis

cus

10

Lateral gutter

32

46

87

9

1

5

Lateral view on lateral gutter; 30° arthroscope

Late

ral m

enis

cus

Pop

liteu

s te

ndon

Popliteus h

ole

10

Posterior compartment

32

46

87

9

1

5

Medial view, scope along posterior cruciate to posteromedial pouch; 30° arthroscope

Medial fem

oral condyle

Poste

rior h

orn

Med

ial m

enisc

us

10

Variation of normal

32

46

87

9

1

5

Medial fem

oral condyle

Medial femoral condyle

Plica

Plica

Patella

Medial view of the medial plica; 30° arthroscope

10

Variation of normal

32

46

87

9

1

5

Medial fem

oral condyle

Plica

Posterolateral view of the anterior plica, ligamentum Mucosum; 30° arthroscope

10

Anterior

cruciate

Variation of normal

32

46

87

9

1

5

Lateral femoral condyle

Discoid lateral meniscus

Postero lateral view of a discoid meniscus (this on 80% discoid); 30° arthroscope

10

Always mark the involved side and relevant anatomical structures.Never use sharp trocars, always bluntly instruments.Prior to surgery pressure the tourniquet at 350 mmHg on the involved upper leg, use gravity, pressure saline bags or arthroscopic pumps for irrigation.Always perform an examination of the knee including stability testing prior to arthroscopy.Start the arthroscopy with applying the antero-lateral portal and insert the scope along the lateral edge of the patella with the knee in extension and while lifting the patella.Apply the following portals guided by the arthroscopic view, using a needle if convenient.Always perform the arthroscopic evaluation of all parts of the knee before performing any arthroscopic surgery.Always use a probe to examine menisci, joint cartilage and ligements while overlooking the different structures.

Take home points

Questionnaire

What is the importance of the antero-lateral portal

Explain how to identify the antero-medial portal

Which subcutaneous nerve is at risk applying the antero-

medial portal

Which anatomical structures are the landmarks when applying

the postero-medial portal

What intraarticular structure should not be mistanken for the

anterior cruciate ligament