Knee Contusions and Stress Injuries. Laura W. Bancroft, M.D.

Transcription

1 Knee Contusions and Stress Injuries Laura W. Bancroft, M.D.

2 Objectives Review 5 types of contusion patterns Pivot shift Dashboard Hyperextension Clip Lateral patellar dislocation Demonstrate various stress injuries, including patellofemoral stress syndrome

3 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

4 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

5 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

6 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

7 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

8 Pivot Shift Knee valgus, femur internally rotated Deceleration-rotational-valgus stress ACL rupture Impaction of lateral femoral condyle against posterolateral tibial plateau Location of femoral condylar edema depends on degree of flexion Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

9 Children Tibial Eminence Fractures 90% - subchondral bone contusions Lateral femoral condyle 80% Lateral tibial plateau 80% Medial femoral condyle 60% Medial tibial plateau 30% Shea KG et al. Bone bruises and meniscal tears on MRI in skeletally immature chidlren with tibial eminence fractures. J Pediatr Orthop 2011; 31:150-2.

10 Children Tibial Eminence Fractures 90% - subchondral bone contusions Lateral femoral condyle 80% Lateral tibial plateau 80% Medial femoral condyle 60% Medial tibial plateau 30% Shea KG et al. Bone bruises and meniscal tears on MRI in skeletally immature chidlren with tibial eminence fractures. J Pediatr Orthop 2011; 31:150-2.

11 Children May have intact ACL with typical pivot shift bone contusions 28% of cases Ligamentous laxity Snearly WN et al. Lateral-compartment bone contusions in adolescents with intact anterior cruciate ligaments. Radiology 1993; 198:205-8.

12 Dashboard Injury Force applied to anterior proximal tibia while knee in flexed position Disruption of PCL and posterior capsule Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

13 Dashboard Injury Force applied to anterior proximal tibia while knee in flexed position Disruption of PCL and posterior capsule Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

14 Dashboard Injury Force applied to anterior proximal tibia while knee in flexed position Disruption of PCL and posterior capsule Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

15 Dashboard Injury Force applied to anterior proximal tibia while knee in flexed position Disruption of PCL and posterior capsule Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

16 Dashboard Injury Force applied to anterior proximal tibia while knee in flexed position Disruption of PCL and posterior capsule Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

17 Subacute Dashboard Injury

18 Hyperextension Direct force is applied to anterior tibia while foot is planted Indirect force - forceful kicking Direct injury (car bumper hitting anterior tibia of pedestrian) Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

19 Hyperextension Anterior aspect of tibial plateau strikes anterior femoral condyle Kissing contusion +/- ACL, PCL or meniscal injury Dislocation + popliteal neurovascular injury Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

20 Hyperextension Anterior aspect of tibial plateau strikes anterior femoral condyle Kissing contusion +/- ACL, PCL or meniscal injury Dislocation + popliteal neurovascular injury Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

21 Clip Injury Contact injury Pure valgus stress applied to knee while knee is mildly flexed American football players Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

22 Clip Injury Bone marrow edema Most prominent in lateral femoral condyle - direct blow Second smaller area of edema in the medial femoral condyle - avulsive stress to the MCL Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

23 Clip Injury Bone marrow edema Most prominent in lateral femoral condyle - direct blow Second smaller area of edema in the medial femoral condyle - avulsive stress to the MCL Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

24 Clip Injury +/- MCL sprain or disruption Most common proximal ligament near femoral attachment Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

25 Clip Injury +/- MCL sprain or disruption Most common proximal ligament near femoral attachment Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

26 Clip Injury +/- MCL sprain or disruption Most common proximal ligament near femoral attachment Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

27 Lateral Patellar Dislocation Most common mechanism of first-time patellar dislocation Flexed, internally rotated knee Planted foot Valgus component Sanders TG et al. Bone contusion patterns of the knee at MR imaging. RadioGraphics 2000; 20:S

28 Lateral Patellar Dislocation Most common mechanism of first-time patellar dislocation Flexed, internally rotated knee Planted foot Valgus component Diederichs G et al. MR imaging of patellar instability. RadioGraphics 2010; 30:

29 Acute Traumatic Patellar Dislocation Contusions 100% - lateral femoral condyle 96% - patella 30% - medial femoral condyle * 12 month follow-up 22% - femoral condylar contusion 39% - patellar contusion Paakkala A et al. Bone bruise in acute traumatic patellar dislocation. Skeletal Radiol 2010; 39:

30 Acute Traumatic Patellar Dislocation Contusions 100% - lateral femoral condyle 96% - patella 30% - medial femoral condyle * 12 month follow-up 22% - femoral condylar contusion 39% - patellar contusion Paakkala A et al. Bone bruise in acute traumatic patellar dislocation. Skeletal Radiol 2010; 39:

31 Acute Traumatic Patellar Dislocation Contusions 100% - lateral femoral condyle 96% - patella 30% - medial femoral condyle * 12 month follow-up 22% - femoral condylar contusion 39% - patellar contusion Paakkala A et al. Bone bruise in acute traumatic patellar dislocation. Skeletal Radiol 2010; 39:

32 PDRS patellofemoral ligament rupture

33 PDRS cartilage sheared

34 * PDRS cartilage sheared

35 PDRS osteochondral fragment

36 PDRS osteochondral fragment

37 PDRS osteochondral fragment

38 PDRS osteochondral fragment

39 PDRS osteochondral fragment

40 Stress Injuries

41 Stress changes throughout medullary canal

42 Stress fracture excessive jump roping

43 Avulsive injury at MCL origin valgus stress

44 Stress fracture - runner

45 Stress fracture

46 Stress fracture

47 Stress fracture

48 Insufficiency fracture

49 Insufficiency fracture

50 Patellofemoral Stress Injuries - Children Sinding-Larsen-Johannson disease Osgood-Schlatter Patellar sleeve avulsion Tibial Tuberosity Avulsion

51 Sinding-Larsen-Johannson Disease Umbrella term for syndrome that causes pain at inferior pole of patella Fragmentation or calcification of inferior pole Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

52 Osgood-Schlatter Disease Traction apophysitis Strong forces from quadriceps mechanism Insertion of patellar tendon on tibial tuberosity Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

53 Osgood-Schlatter Disease Common causes of anterior knee pain y/o boys 8-12 y/o girls Repeated jumping/squatting Local pain, swelling and tenderness at tuberosity Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

54 Osgood-Schlatter Disease T2 - High signal within and surrounding tendon Deep infrapatellar bursitis

55 Osgood-Schlatter Disease T2 - High signal within and surrounding tendon Deep infrapatellar bursitis

56 Patellar Sleeve Avulsion Acute counterpart to Sinding-Larsen Johannson Acute jumping injury 8-12 y/o Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

57 Patellar Sleeve Avulsion Anterior soft tissue swelling Small fragment of bone avulsed from inferior tip or anterior inferior patella Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

58 Patellar Sleeve Avulsion Osseous fragments - tip of the iceberg Much larger cartilage fragment unseen on radiographs MR identify size of cartilage fragment Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

59 Patellar Sleeve Avulsion Adolescent boy jumpers near skeletal maturity Sharp fragments are visible and elevated on radiographs Davis KW. Imaging pediatric sports injuries. Radiol Clin N Am 2010; 48:

60 Tibial Tuberosity Avulsion

61 Tibial Tuberosity Avulsion

62 Conclusion Pivot shift injury is caused by decelerationrotational-valgus stress, has associated ACL rupture, and impaction contusions of lateral femoral condyle and posterolateral tibial plateau Dashboard injuries are caused by forces applied to the anterior proximal tibia while knee is in flexed position, and leads to disruption of the PCL and posterior capsule

63 Conclusion Hyperextension injuries are caused by the anterior tibial plateau striking the anterior femoral condyle, leading to kissing contusions, with or without ACL, PCL and meniscal injury Clip injuries result from pure valgus stress applied to mildly flexed knee, resulting in large lateral femoral condylar contusion and smaller medial femoral condylar avulsive injury

64 Conclusion Lateral patellar dislocation occurs when valgus force is applied to the flexed, internally rotated knee when the foot is planted. Lateral femoral condylar and medial patellacontusions occur, often in conjunction with patellofemoral ligament sprain or tear.

65 Conclusion Linear stress and insufficiency fractures occur commonly in the proximal tibia, fibula or subchondral femur. Patellofemoral stress syndrome (Sinding- Larsen-Johannson disease, Osgood-Schlatter disease, patellar sleeve avulsion and tibial tuberosity avulsion) is the most common cause of chronic anterior knee pain in adolescents.