Knee Injuries in Sport

What are the 6 movements of the knee joint?
Flexion, extension, internal rotation, external rotation, Valgus (abduction) and varus (adduction)
1 of 60
Define Muscle
contains contains contractile filaments which change the size if the muscle, therefore producing muscular force
2 of 60
Define Tendon
connects muscle to bone. It has to withstand tensions as it transfer the muscle force to the bone to initiate movement
3 of 60
What is the musculotendinous unit/junction?
The muscle and tendon connection: tendon transfering the muscle force to the bone for movement
4 of 60
Define ligament
Connects bone to bone. Maintains joint stability
5 of 60
Structure of the knee: What are the 4 bones of the knee joint?
Femur, Tibia, Fibula and Patella
6 of 60
Structure of the knee: What are the 4 ligaments of the knee?
Anterior cruciate ligament (ACL), Posterior cruciate ligament (PCL), Medial collateral ligament (MCL) and Lateral collateral ligament (LCL)
7 of 60
Structure of the knee: what are the 2 areas of the meniscus?
Medial Meniscus and Lateral Meniscus
8 of 60
Structure of the knee: What part of the knee ensures supple joint movement?
Cartilage
9 of 60
What is the main purpose of the ACL?
Major stabilising ligament for the knee. Strong internal brace for the knee.
10 of 60
How is the ACL commonly injured?
Violent pivoting and twisting of the knee joint.
11 of 60
Whats sports is an ACL injury common?
Football, handball, rugby, americal football, skiing
12 of 60
What are symptoms of an ACL injury?
Pain, locking of joint, reduced ROM, acute inciting event, 'pop' sound, cannot continue plat, Anterior tibial translation, severe haemarthrosis (bleeding), immediate swelling
13 of 60
What is the difference in swelling beterrn an ACL injury and a meniscus injury?
ACL injury has immediate swelling, Meniscus injury swelling takes up to 24 hours to show as limited blood supply
14 of 60
Describe the functions of a meniscus?
Acts as the shock absorber for the knee, reduce the stress applied to the articular cartilage
15 of 60
Why is the meniscus difficult to heal?
Limited blood suppy to the peripheries of the meniscus.
16 of 60
When is the meniscus usually injured?
Pivoting and twisting motion of the knee.
17 of 60
What are symptoms of a meniscus injury?
Swelling occuring over a longer time (e.g. 24 hours), locking sensation caused by the torn meniscus jamming into the joint.
18 of 60
Why is it important to opperate quickly if there is loss of joint motion?
Arthroscopy meniscus repain or partial menisectomy within 2 weeks (once swelling is gone) or the joint may suffer from long term loss of joint motion (e.g contracture). Especially important if the knee cannot extend fully.
19 of 60
What does a 'knee-in-toe-out' injury effect?
The ACL, Lateral Meniscus and MCL
20 of 60
What is the clinical prevalance of a 'knee-in-to-out' injury?
49.5%
21 of 60
What does a 'knee-out-toe-in' injury effect?
ACL, Medial meniscus and LCL
22 of 60
What is the clinical prevalance of a 'knee-out-toe-in' injury?
8.9%
23 of 60
What are other possible knee injuries with rotation?
Internal/external, adduction(valgus)/abduction(varus), and flexion/extension
24 of 60
What are other possible knee injuries with translation?
Distraction/compresstion, medial/lateral, posterior/anterior
25 of 60
What is a key element of all knee injuries?
Excessive motion in either translation or rotational directions
26 of 60
Who are Tron Krosshaug and Roald Barh and what did they develop?
Researchers based in Oslo. Developed a model-based image-matching (MBIM) motion analysis technique.
27 of 60
What did their study involve?
Collecting video data on injuries, scale a skeleton model to patient and then conduct MBIM analysis to obtain knee joint kinematics data.
28 of 60
What did they find?
In 10 ACL rupture injuries; there was excessive abnormal secondary (internal.external rotation) and tertiary (adduction/abduction) joint motion observed within 40ms after foot strike.
29 of 60
What were the 3 movements they found to change causing injury?
Abduction (valgus) increased 10-13 degrees at 40ms, External rotation of 5 degrees on foot strike internally rotated to 8 degrees at 40ms. Knee externally rotated to 17 degrees at 40ms.
30 of 60
What is 'Genu Valgum'?
'knock-knees' where the knees bend inwards towards each other
31 of 60
What is 'Genu Varum'?
'Bow-legged' where the knees point outwards
32 of 60
What are the 3 tests for an ACL injury?
Lachmans test, anterior drawer test and pivot shift test
33 of 60
Describe the Lachmans Test
Knee flexed at 30 degrees, apply anterior stress to the tibia, signs of anterior subluxation
34 of 60
Describe the Anterior Drawer Test
Knee flexed at 90 degrees, apply anterior stress to the tibia, signs of anterior subluxation
35 of 60
Describe the Pivot Shift Test
Patient supine and hip flexed to 30 degrees. Hold lower leg + ankle + maintain 20-degree internal tibial rotation. Apply valgus force + flex knee to feel subluxation. Reduction of subluxed tibia with flexion - iliotibial band goes extensor to flexor
36 of 60
How can you diagnose an ACL rupture?
Magnitic Resonance Imaging (MRI)
37 of 60
What does a normal ACL look like under MRI?
Solid black band showing the intact ACL
38 of 60
What does a torn ACL look like on an MRI?
Disrupted ligament appears lighter in colour. Sometimes ou may see breakage or a disorganised pattern
39 of 60
Name and describe the Physical examination test for a Meniscus Injury
McMurray Test = examine focal joint line tenderness by holding heel and twisting lower leg (knee flexed to 90 degrees). Look at patients reaction. feel for clicking and ask patients if it feels tender.
40 of 60
What level of MRI is necessary for diagnosis meniscus and cartilage?
Meniscus/ACL = 1.5T (tesla). Cartilage = 3T
41 of 60
What 3 things does a partial menisectomy do?
1) Preserve the un-injured meniscus, 2) repair the injured meniscus, 3) remove the debris which restricts the joint motion
42 of 60
What are the 4 main goals for ACL injury management?
1) restore knee joint stability (prevent giving way), 2) restore knee joint motion, 3) restore muscle function (atrophy after dis-use, 4) Return to pre-injury activity level
43 of 60
What are the 4 steps in ACL reconstruction?
1 - remove the torn ACL, 2 - drill tunnels at femur and tibia, 3 - pass the graft through the tunnels, 4 - fix the graft with screws
44 of 60
What is an autograft?
From one site to another on the same patient
45 of 60
What is an Allograft?
From one patient to another patient (e.g. organ transplant)
46 of 60
What is an Xenograft?
From one species to another (e.g. from animal to human)
47 of 60
What is the comparative strength of a 'Bone-patellar tendon-bone (BPB, BTB) graft to ACL strength?
140% of ACL strength
48 of 60
What is the comparative strength of a hamstring tendon graft (semitendinosis, gracilis) to ACL strength?
70% of ACL strength
49 of 60
Describe progressive bone-to-tendon healing
progressive mineralisation of the interface tissue occurs. Bone grows into outer tendon. Collagn fibers re-establish and tendon-bone junction restored
50 of 60
What are the 3 cellular level modalities to promote bone-to-tendon healing?
1) transforming growth factor (beta 1), 1) Bone morphogenetic proteins-2 (BMP2), 3) Mesenchymal stem cells
51 of 60
What are the 2 biometerial modalities to promote bone-to-tendon healing?
1) Demineralised bone matrix, 2) injectable calcium phosphate cement
52 of 60
What are the 3 biophysical intervention modalities to promote bone-to-tendon healing?
1) low-intensity pulsed ultrasound (LIPUS), 2) shockwave therapy, 3) Ultrasound guided shock wave therapy
53 of 60
What can periosteum do?
It is a new modality containing multipotent mesodermal cells, as well as chondro-progenitor and osteo-progenitor cells which can form cartilage and bone under appropriate conditions
54 of 60
What is a double-bundle ACL reconstruction?
Two bundles: Antero-medial (AM) bundle for translation and postero-lateral (PL) bundle for rotational stability (proposed by Freddie Fu)
55 of 60
What does a static rotational stability test involve?
Attach torque sensor to book, measure applied stress (torque), attack motion trackers to measure tranverse plane rotation.
56 of 60
What did the experiment test?
Measures the total internal-to-extermal rotation while appling 5Nm internal and 5Nm external rotational torque. data collection ongoing to establish threshold.
57 of 60
What does the dynamic function test aim to do?
show how the patient could cope with a demanding task. it is good for gross evaluation but perhapps not in-vivo joint motions.
58 of 60
What is a Biplanar x-ray motion analysis with C-arm?
2 cameras view the bone boundary. Determine kinematics data with patient-specific 3D model. C-arm not designed with room for measurement, only good for static or squatting measurement.
59 of 60
What does computational modelling allow physicians to try?
the fine element analysis allows physicians to 'try' different surgical methods (i.e. graft size, tunnel position, tunnel angles, single/double bundle etc)
60 of 60

Other cards in this set

Card 2

Front

Define Muscle

Back

contains contains contractile filaments which change the size if the muscle, therefore producing muscular force

Card 3

Front

Define Tendon

Back

Preview of the front of card 3

Card 4

Front

What is the musculotendinous unit/junction?

Back

Preview of the front of card 4

Card 5

Front

Define ligament

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Human Biology resources:

See all Human Biology resources »See all Knee Injury resources »