The knee joint contains bony structures like the patella, femoral condyles, and tibial plateaus. It also contains soft tissues like the medial and lateral menisci and anterior and posterior cruciate ligaments. The menisci function to distribute joint fluid, absorb shock, deepen the joint, stabilize the joint, and bear weight. Meniscal tears are most commonly longitudinal tears of the posterior horn of the medial meniscus caused by rotation of the flexed knee. Diagnosis involves history, physical exam including tests like McMurray's and Thessaly, and imaging like MRI. Treatment involves initial immobilization and rehab followed by possible surgical repair, removal, or replacement of torn meniscal tissue.

2. OSSEOUS STRUCTURES
3 components: patella,
distal femoral condyles,
& the proximal tibial
plateaus, or condyles.

3. Medial & lateral menisci & anterior & posterior cruciate lig.
FUNCTION -distribution of joint fluid, nutrition, shock
absorption, deepening of jt, stabilization of jt, & wt-bearing fn.
Cruciate ligaments function as stabilizers of jt & axes around which rotary
motion, both normal & abnormal, occurs.
They restrict the backward & fwd motion of tibia on femur &
assist in control of both MR & LR of tibia on femur.
ER of tibia produces an unwinding of the lig., &
IR produces a winding up of cruciate lig.
INTRAARTICULAR STRUCTURES

4. Posterior view
Anterior view
Superior view
Right knee joint
ACL
PCL
LM
FCL
MM
TCL
Patellar
ligament
FCL

5. MECHANICS
EXTERNAL ROTATION

6. Neutral rotation-

7. In internal rotation-

8. Superior view of tibial condyles after
removal of femur
MENISCI
POPLITEAL
TENDON
Anterior
meniscofemoral lig
PMFL
PCL
MM
LM

9. Posterior view of knee after removal of
femur.
Prevent capsular & synovial
impingement during flexion-
extension movts.
- joint lubrication fn, helping
to distribute synovial fluid
throughout the joint &
aiding nutrition of articular
cartilage
-contribute to stability in all
planes but are especially
important rotary stabilizers
Menisci
PCL
Post.Horn
of lm
popliteus

10. Pattern of collagen
fibres within
meniscus
Radial
Circumferential

11. Vascular supply
FEMUR
TIBIA

12. MENISCAL TEAR
• Mech - Rotation as the flexed knee moves toward an extended
position.
• Medial meniscus, being far less mobile on the tibia, can become
impaled b/n the condyles, & injury can result.
• M/C location for injury - posterior horn of meniscus
• M/C type of injury - longitudinal tears.
• Length, depth & position of tear depends on posterior horn position
in relation to femoral & tibial condyles at the T.O.I.

13. Classification
- based on the type of tear found at surgery.
(1) longitudinal tears,
(2) transverse and oblique tears,
(3) a combination of longitudinal and transverse tears,
(4) tears associated with cystic menisci, and
(5) tears associated with discoid menisci.

14. Meniscial cyst are freq. asso. with tears & are 9 times more
common on lateral than on medial side.
Discoid menisci are abnormal, & because of hypermobility & the
bulk of tissue b/n the articular surfaces, they are vulnerable to
compression & rotary stresses. Degeneration within the discoid
meniscus, as well as tears, may develop.

15. DIAGNOSIS
• Menisci tears can be divided into two groups: those in which there is
locking and the diagnosis is clear, and those in which locking is absent
and the diagnosis is more difficult.
• Locking usually occurs only with longitudinal tears and is much more
common with bucket-handle tears, usually of the medial meniscus.

16. • If a patient does not have locking, the diagnosis of a torn meniscus is
more difficult.
• history of several episodes of trouble referable to the knee, often
resulting in effusion and a brief period of disability but no definite
locking.
• A sensation of “giving way” or snaps, clicks, catches, or jerks in the knee
may be described, or the history may be even more indefinite, with
recurrent episodes of pain and mild effusion in the knee and tenderness
in the anterior joint space after excessive activity.
• a sensation of giving way, effusion, atrophy of the quadriceps, tenderness
over the joint line (or the meniscus), and reproduction of a click by
manipulative maneuvers during the physical examination.

17. Diagnostic test
• McMurray test
• supine
• knee acutely & forcibly flexed
• medial meniscus - palpating posteromedial margin of jt one hand while grasping the foot with
other hand.
• Keeping knee completely flexed, leg is ERknee is slowly extended.
• As the femur passes over a tear in the meniscus, a click may be heard or felt.
lateral meniscus - P/L jt margin, IR leg as far as possible, & slowly extending knee while listening
and feeling for a click. A click produced by the McMurray test usually is caused by a posterior
peripheral tear of the meniscus and occurs between complete flexion of the knee and 90 degrees.
Popping, which occurs with greater degrees of extension when it is definitely localized to the joint
line, suggests a tear of the middle and anterior portions of the meniscus. The position of the knee
when the click occurs thus may help locate the lesion.
• Apley s grinding test

18. Thessaly test
Karachalios et al. described a test for early detection of meniscal tears
Reported diagnostic accuracy rates of 94% in medial meniscus tear
& 96% lateral meniscus tear.
Examiner – holds pt outstretched hands while pt stands flatfooted on floor. Pt
rotates knee & body, internally & externally, 3 times with knee in slight flexion (5
degrees). The same procedure is carried out with the knee flexed 20 degrees.
Patients with suspected meniscal tears experience medial or lateral joint-line
discomfort and may have a sense of locking or catching.
Test - normal knee first to teach the patient how to keep the knee in 5 and 20
degrees of flexion and how to recognize a possible positive result in the
symptomatic knee.
Thessaly test at 20 degrees of knee flexion was suggested to be effective as a first-
line clinical screening test for meniscal tears.

19. IMAGING STUDIES
• RADIOGRAPHY
• AP, lateral, and intercondylar notch views with a tangential view of
the inferior surface of the patella should be routine.
• Ordinary radiographs will not confirm the diagnosis of a torn
meniscus but are essential to exclude osteocartilaginous loose bodies,
osteochondritis dissecans, and other pathological processes that can
mimic a torn meniscus.

20. Normal meniscus sagittal
image—the bow-tie
appearance

21. Normal meniscus coronal.
Note the triangular
appearance and dark
signal

22. Tear of the posterior horn of
the medial meniscus

23. Displaced bucket handle tear with
double posterior
cruciate ligament sign

24. RADIAL TEAR

25. LONGITUDINAL TEAR

27. • High-resolution CT
- sensitivity of 96.5%
- specificity of 81.3%, and
- accuracy of 91%.
- CT for examining the patellofemoral joint because it allows
evaluation of normal & abnormal relation of articulation at various
degrees of knee flexion, with & without quadriceps contraction.

28. Nonsurgical management
• groin-to-ankle cylinder cast or knee immobilizer worn - 4 to 6 weeks.
• Crutch walking with toe touch wt bearing is permitted when pt gains
active control of the extremity in the cast.
• To strengthen the quadriceps, hamstrings, and gastrocnemius and
soleus muscles around the knee as well as the flexors, abductors,
adductors, & extensors around the hip- Progressive isometric exercise
program during the time the leg is in the cast

29. • At 4 to 6 weeks, immobilization is discontinued & rehabilitative
exercise program for the muscles around hip & knee is intensified.
• Patient must be informed that any tear in the meniscus may not have
healed despite this period of immobilization.
• If symptoms recur after a period of nonoperative Rx, surgical repair
or removal of damaged meniscus may be necessary, & more specific
diagnostic procedures, such as MRI & arthroscopy, are used as
indicated.

30. OPERATIVE MANAGEMENT
Total
meniscectomy
Subtotal
meniscectomy
degenerative
changes

31. Operative Mx
• Amt of degenerative change in the articular cartilage is directly
proportional to amt of meniscus removed.
• If the derangement produces almost daily symptoms, frequent
locking, or repeated or chronic effusions, the pathological portion of
the meniscus should be removed because problems caused by
present disability far outweigh the probability or significance of future
degenerative arthritis.
• If a significant portion of the peripheral rim can be retained by
subtotal meniscal excision, the long-term result is improved.

32. • Complete removal of meniscus is justified only when it is irreparably
torn, & the meniscal rim should be preserved if at all possible.
• Total meniscectomy is no longer considered Rx.O.C in young athletes
or other people whose daily activities require vigorous use of the
knee.

33. • OPEN MENISCAL REPAIR
• MENISCAL AUTOGRAFTS AND ALLOGRAFTS

34. THANK U
• Source - campbell