- The patient is a 54-year-old female who was in a motorcycle accident 4 hours prior where her motorcycle was hit on the side causing her to fall and injure her left leg. - On examination, she had swelling and deformity of her left knee and thigh with tenderness and limited range of motion. X-rays showed a posterolateral dislocation of the left knee. - She underwent closed reduction of the knee dislocation. A CTA showed no evidence of vascular injury. She was diagnosed with a posterolateral left knee dislocation and given splinting and pain management.

1. Extern
Conference
Ext. ศิริลักษณ์ วศินะจินดาแก้ว
วันที่ 14 ธันวาคม 2559

2. Patient Profile
• ผู้ป่วยหญิง อายุ 54 ปี
• ภูมิลาเนา อาเภอพิมาย จังหวัดนครราชสีมา
• อาชีพ ค้าขาย

3. Chief complain
 ปวดขาซ้าย 4 ชั่วโมง ก่อนมาโรงพยาบาล

4. Present illness
4 ชั่วโมงก่อนมาโรงพยาบาล ขับ MC ถูกMC ชนที่บริเวณด้านข้าง
ล้ม ได้รับบาดเจ็บที่ขาซ้าย มีขาซ้ายผิดรูป ไม่มีแผลฉีกขาด หลังล้มไม่
สามารถยืนหรือเดินได้ ไม่สามารถงอเข่าซ้ายได้ ปวดที่ขาซ้ายมาก ไม่
ชา ไม่มีประวัติสลบ จาเหตุการณ์ได้ ผู้พบเหตุการณ์โทรแจ้งรถกู้ภัย
นาส่งโรงพยาบาล

6. Primary survey
A : Can speak , c-spine not tender, full ROM
B : Equal breath sound both lungs, CCT- neg
C : BP 122/75 mmHg , PR 72 bpm , PCT- neg
no active external hemorrhage
D : E4V5M6 , Pupil 3 mm RTLBE
E : Lt. thigh and Lt. knee swelling ,tenderness,
deformity,limit ROM of Lt.knee due to
pain,instability

7. Secondary survey
• A : No drugs and food allergy
• M : No current medication
• P : Unknown underlying disease
• L : 16.00 , 12/12/2559
• E : ขับ MC ถูกMC ชนที่บริเวณด้านข้างล้ม ได้รับบาดเจ็บที่ขาซ้าย
มีขาซ้ายผิดรูป คู่กรณีได้รับบาดเจ็บมีกระดูกแขนหัก รักษาที่รพช. ไม่มี
ผู้เสียชีวิตจากเหตุการณ์ดังกล่าว

8. Head to Toe examination
• Head and Maxillofacial :
– LW 0.5x2 cm at upper eyelid, not tear canaliculi,
no subconjunctival hemorrhage
– AW 5x5 cm at Lt.side of face , tenderness,swelling, no stepping
• Cervical spine and Neck :
– Not tender at posterior midline of neck
• Chest :
– Clear and Equal breath sound both lungs
• Abdomen :
– No distension,normoactive bowel sound soft,not tender
• Extremities : as picture

9. • Inspection:
– Lt. knee and Thigh marked swelling ,deformities, ecchymosis at popliteal fossa
– Abrasion wound 3x3 cm at posterior of Lt. thigh
• Palpation :
– Tenderness at Lt. patellar, along j
– Ballotment cannot examine due to pain
• Range of motion :
– Limit ROM of Lt.Knee and Lt. Hip
• Neurovascular :
– Dorsalis pedis 2+ both side
– ABI = 1

10. Problem lists
• Lt. knee fracture and deformity
• R/o vascular injury
• Mild head injury ( low risk )
• LW at Left upper eye lid

11. Differential diagnosis
• Fracture Left patella
• Fracture Left distal femur
• Fracture Left proximal tibia
• Left Knee dislocation
• Ligament injury

12. Film Left knee ( AP )

13. Film Left knee ( lateral )

14. Diagnosis
• Posterolateral Left Knee dislocation with R/O
vascular injury
• Mild head injury ( low risk )
• LW at Left upper eye lid

15. Management
• Initial management At ER
Consult trauma R/O vascular injury
- วัด ABI = 1 (ทั้งก่อนและหลัง closed reduction)
– Closed reduction
– On posterior long leg slab
– CTA Lower extremities : No evidence of vascular
injury

16. Knee Dislocation

17. Anatomy

19. Epidemiology
• Rare
• high-energy :
– usually from MVC or fall from height
– commonly a dashboard injury resulting in axial
load to flexed knee
• Low – energy:
– Athletic injury

20. Associated injuries

21. Associated injuries

22. Classification
• based on direction of displacement of the tibia

23. • Anterior
- most common type of dislocation (30-50%)
– due to hyperextension injury
– usually involves tear of PCL
– arterial injury is generally an intimal tear due to
traction
• posterior
– 2nd most common type (25%)
– due to axial load to flexed knee (dashboard injury)
– highest rate of complete tear of popliteal artery
Classification

24. • Lateral
- 13% of knee dislocations
– due to varus or valgus force
– usually involves tears of both ACL and PCL
– highest rate of peroneal nerve injury
• Medial
– varus or valgus force
– usually disrupted PLC and PCL
• Rotational
– posterolateral is most common rotational dislocation
– usually irreducible
Classification

25. Presentation
• Symptoms
– history of trauma and deformity of the knee
– knee pain & instability

26. Sign
• appearance
• 50% spontaneously reduce before arrival to ED
(therefore underdiagnosed)
• swelling, effusion, abrasions
• Deformity (do not wait for radiographs, reduce
immediately, especially if absent pulses )
• "dimple sign"

27. Dimple sign

28. Sign
• vascular exam
– palpate the dorsalis pedis and posterior tibial pulses
• if pulses are present and normal
– does not indicate absence of arterial injury
– measure Ankle-Brachial Index (ABI)
• If pulses are absent or diminished
– perform immediate reduction and reassessment
– immediate surgical exploration if pulses are still absent
following reduction
ischemia time >8 hours has
amputation rates as high as 86%

29. Imaging
• Radiographs
– may be normal if spontaneous reduction
• look for asymmetric or irregular joint space
• look for avulsion fxs (Segond sign - lateral tibial condyle
avulsion fx)
• osteochondral defects
• MRI
– required to evaluate soft tissue injury (ligaments,
meniscus) and for surgical planning
– obtain MRI after acute treatment

30. Managemant
• Initial Treatment
– reduce knee and re-examine vascular status
• considered an orthopedic emergency
• splint knee in 20-30 degrees of flexion
• confirm reduction is held with repeat radiographs in
brace/splint

31. • Operative
– emergent surgical intervention
• indications
– vascular injury repair (takes precedence)
– open fx and open dislocation
– irreducible dislocation
– compartment syndrome
Managemant

32. Delayed ligamentous reconstruction/repair
• indications
– patients can be placed in a knee immobilizer for 6 weeks for
initial stabilization
» improved outcomes with early treatment (within 3
weeks)
Managemant

33. ขอบคุณค่ะ