meniscal injuries

Dr . SAYF ALDEEN HUSSAMDr . SAYF ALDEEN HUSSAMALAL-WASITY TEACHING HOSPITAL-WASITY TEACHING HOSPITAL

●Menisci is a crescentric

shaped fibrocartilagenous

structures between the

condyles of femur & tibia

●Peripheral edges are thick,

convex& fixed to inner

surface of capsule.

●Triangular in cross section

●Covers peripheral 2/3 rd of

articular surface.

●Each menisci has

2 ends---- anterior and posterior

horns

2 borders----outer and inner border

2 Surfaces ---upper and lower

C shaped, larger in radius than lateral

meniscus Anterior horn: Attached anterior

to intercondylar eminence and to the ACL

Posterior horn: Attached in front of

attachment of PCL, posterior to the

intercondylar eminence

Entire peripheral border firmly

attached to the medial capsule and through

coronary ligament to the upper border of

tibia

Smaller, More circular, thicker in

periphery, wider in body and

more mobile than medial

meniscus

ANTERIOR HORN: attached medially in

front of the intercondylar

eminence POSTERIOR HORN:

inserts into the posterior aspect

of the intercondylar eminence

Attached posteriorly to the

medial femoral condyle by

either the ligament of Humphry

or the ligament of wrisberg

●outer one-third: supply from the peripheral meniscal plexus, in turn formed from the medial, lateral and middle genicular arteries 

●inner two-thirds: no vascular supply; diffusion dependent 

VASCULAR ZONES

●Red-red zone: fully vascular

●Red-white :minimal blood

supply

●White-white: fully avascular

●outer one-third innervated by posterior articular branch of the tibial nerve and terminal obturator and femoral nerve branches 

●posterior horns have highest concentration of mechanoreceptors

●The inner two-thirds has no nerve fibers.

1-Joint lubrication2-Joint stability- ( rotary)

3-Shock absorbers-reduce the stress on articular cartilage

4-Load bearing function5-Deepening the cavity

6 -Prevents impingement during joint motion.7-Medial meniscus – provides stability to Anterior

Cruciate Ligament deficient knees.(ACL)

●occur with rotational force ,on a partially flexed knee

like Foot ball players

●Most common site- posterior horn

●Most common type- longitudinal tear

●Length ,depth, position of tear depend on the position

of the meniscus in relation to condyles at the time of

injury.

1-Trauma

2-Meniscal cyst

3-Decreased mobility of the meniscus

4-Discoid meniscus

5-Aging- degeneration

6-Abnormal mechanical axis- ligamentous laxity.

7-Congenitally relaxed joints

8-Inadequate tone and musculature.

1-Longitudinal tears

2-Horizontal tears

3-Oblique tears

4-Radial tears

5-complex tears

●Most common type

●affect young pt.

●Post trauma

●2 types:

- Vertical incomplete tear

- Vertical complete: Displaced

tear (bucket handle)

●Extend from inner margin to

capsule horizontally

●Common in posterior horn

of medial meniscus & lateral

meniscus

●Full thickness tear extending obliquely

from the inner margin into the body

●Types:

-Anterior oblique

-posterior oblique

●Commonly seen at the junction of

middle & posterior 1/3 of medial

meniscus

●Extend radially from inner margin into

the body

●Common in middle 1/3 of lateral

Meniscus

: ●types-complete

-incomplete

-parrot beak tear-(Radial tear

with longitudinal or oblique extension)

●Combination of all the above

●Common in chronic meniscal lesions & degenerative

menisci

●Predisposing conditions:

* Discoid lateral meniscus

* Meniscal cyst

* Calcium pyrophosphate deposition

●History :

*May be asymptomatic

*Pain

*Sports injuries

*Trauma

*Giving way

*Locking

●Physical signs:

*Effusion

*Quadriceps wasting

*Joint line tenderness

*Limitation of movements.

●Mc Murray test .

●Apley’s grinding test

●For medial meniscus tear

Fully flex the knee

Externally rotate the leg

Keep the fingers on the medial joint line.

Then Slowly abduct and external rotate the

knee.

Click and pain is indicative

●For lateral meniscus tear:

Fully flex knee ,internally rotate and extend the leg.

If a click or pain is indicative

●confirms this after examining the other normal knee for clicks of other

origins like tendon and soft tissues snapping etc.

*Prone position

*Bend examiner knee and press the

patients thigh.

*Hold the ankle and the foot by both

hands

*Compress the leg downwards and

rotate internaly and externally.

*If patient elicit pain it indicated

meniscal tear

*X-Ray-Antero posterior ,lateral view of knee &

intercondylar notch view

*MRI

*Arthroscopy

*Arthrography

Grade I –increase in signal,not extending to articular surfaceGrade II- linear increased density, not extending to articular surface

GradeIII- signal extending to articular surface

*Gold standard for diagnosis and treatment

*Thorough inspection of menisci, ligaments &cartilage

is possible

*Anteromedial or anterolateral portals

*Full extent ,type, site of tears & degenerative changes

can be seen

NON- SURGICAL

SURGICAL

Indications:

1-Incomplete meniscal tear

2-A small stable peripheral tear (5mm) without any

other injuries.

*Grion-ankle cylindrical cast 4 - 6 weeks

*Toe-touch partial weight bearing

*Rehabilitative exercise program for 6 weeks to

strengthen quadriceps, hamstrings, gastro-soleus

&hip.

Meniscal repair

Meniscectomy

Meniscal transplant

*Depend on the location of the tear, its morphology and patients factors

*indications:1-Peripheral tear(Red on Red region Also on red on

white region)2-Size <1-2 cm

3-Vertical longitudinal tears are ideal*young patient shows better outcome

*Can be done Open or Arthroscopicaly

1-Tear>3 cm

2-Transverse tear even in periphery

3-Flap tear, radial tear, vertical tear with secondary

lesions.

4-Ligament instability

1-inside out technique -considered gold standard

-medial approach to capsule-lateral approach to capsule

2-all inside technique (suture devices with plastic or bioabsorbable anchors)

-most common-many complications (device breakage, iatrogenic chondral

injury) 3-outside in repair

–useful for anterior horn tears-open repair

*Limit knee flexion to 90 degree

*Low impact activity for 3months

*Full activity after 6months

3 types:

1-Partial

2-Subtotal

3-Total

Methods:

Open

Arthroscopic

*Excision of only torn portion of meniscus. :*Indications

1-Tears >5mm from menisco-synovial junction .2-Flap tears

3-Complex and horizontal tears.*Treatment of choice in young adults who require

vigorous activities.:Advantage

Short operating time.

 *requires excision of portion of peripheral rim of meniscus

- Most of the anterior horn and a portion of middle 3 rd of

the meniscus are not resected

*used in complex tears of posterior horn

Indications:

1-if Meniscus is detached from its periphery.

2-extensive meniscal tears and degenerative

Early:1-Haemarthrosis

2-Chronic Synovitis3-Synovial fistulae4-Painful neuromas5-Thrombophlebitis

6-Infection 7-Reflex sympathetic dystrophy

Retained meniscal fragment 8-

Late changes :Degenerative changes within the joint. Fairbank described three changes :

1-Narrowing of joint space

2-Flattening and squaring of femoral

condyle

3-Antero-posterior  ridge formation

By using either meniscal allografts

or autograft fascial material or synthetic menisci scaffolds

Aim: To prevent degenerative changes, in the

post meniscectomy patient Indications :

Patient less than 45 yrs age, with pain and discomfort associated with early OA, without ACL deficiency or significant malalignment

Contraindications :1 -Age more than 60 yrs.

2 -Bony architectural changes.3 -Prior infection .

4 -Significant malalignment .5 -Instability.