2. Diagnosis of Knee Dislocation
H.Mousavi,MD
Deprtment of Orthopaedic Surgery
Esfahan University of Medical Sciences
May 2015,Esfahan

3. Knee Dislocation
Physical examination of patients with knee dislocations is not always reliable because of pain and guarding, spontaneous reduction, or ipsilateral fractures

4. If any of the following present R/O (Spontaneous reduction UNDERDIAGNOSED)
Hyperextension
Popliteal ecchymosis
Vascular insufficiency
Peroneal nerve deficit
Diffuse tenderness but Absence of hemartrosis (capsular disruption)
Obese pt low energy fall

5. Neurovascular examination
Neurovascular examination are mandatory at the time of initial evaluation,before reduction, and after reduction. The extremity distal to the involved knee should be examined thoroughly for color, temperature, and capillary refill. Posterior tibial and dorsalis pedis pulses are palpated and are compared with the contralateral side.

6. Vascular Status
The presence of distal pulses with a warm foot is not a guarantee that an arterial injury is not present. There are multiple reports of vascular occlusion or intimal tears with normal distal pulses; the incidence is reported to be 5% to 15%.
hypotension in the acutely traumatized patient .
Intimal lesions that may initially present with normal pulses.

7. ABI Index
Even if pulses are present, the ankle-brachial index (ABI) should be calculated and rechecked several times.
If the ABI is more than 0.90, close observation is warranted.
If the ABI is less than 0.85, arteriography is indicated.

8. ANKLE BRACHIAL INDEX

9. Femoral arteriography
Questionable circulation or absent peripheral pulses either before or after reduction of a dislocated knee.
An extremity that originally has no pulses, even though satisfactory pulses are restored after reduction.

10. Vascular status of the extremity
CT angiography
MR angiography
Arterial duplex ultrasonography

11. Algorithm for vascular injury in knee dislocation

12. NERVE DAMAGE Peroneal Nerve Motor: EHL, Tib. Anterior, Peroneals
Sensory: dorsum of the foot and 1st web space
Tibial Nerve
Motor: FHL, Gastrosoleus, Tib Posterior
Sensory: Plantar surface and lateral border of the foot

13. Collateral ligaments
Varus/valgus stress to the knee joint both in full extension and at 30 degrees of flexion

14. Lachman Test
The gold standard for testing of the ACL is the Lachman test, which is performed with the knee in 30 degrees of flexi

15. Posterior Drawer test
The PCL is tested with the posterior drawer and sag tests.

16. Dial test
Dial test (at 30° and 90°) (positive if 10-15° difference)

17. Radiographic evaluation
Direction of dislocation and the presence of any concomitant bony injuries
Anteroposterior, lateral, and oblique views should be obtained before and after reduction

18. MRI Evaluation of soft tissue injuries,
the actual site of cruciate and collateral ligament injury
meniscal disorders or injuries
Status of the popliteal tendon in posterolateral corner injury

19. Thanks