Soft Tissue Knee injuries Flashcards
If a patient reports an injury on twisting which ligament is likely to be affected?
ACL
If the injury was caused by a valgus force which ligament is likely to be affected?
MCL
If the injury was caused by a varus force which ligament is likely to be affected?
LCL
If an effusion is present what injury is likely?
Meniscal or cartilage
What is a haemarthrosis?
Blood in joint space caused by ACL injury or a fracture
What recurrent symptoms must you ask about?
Locking
Swelling
Clicking/catching
Patellar dislocation
At what angle of degrees do you do anterior drawer for?
90
At what angle of degrees is the Lachmans test done?
30
What kind of patients tend to get meniscal tears?
Sporting injury in young patients or spontaneous in >40
If a patient has an ACL injury what must you also keep in mind?
Half will have a meniscal tear
What are the 4 types of meniscal tear?
Longitudinal
Radial
Bucket handle
Parrot beak tear
Which type of meniscal tear will not heal?
Radial tears
Why do meniscal tears not heal well in general?
Only the peripheral third has a blood supply
High failure rate in arthroscopic repair
What would an acutely locked knee signify?
Displaced bucket handle meniscal tear
What needs to be kept in mind with a bucket handle tear?
It is potentially repairable and if the knee remains locked an FFD may develop
What would you do if you have a meniscal tear that hasn’t healed or wont heal?
Arthroscopic menisectomy
What can degenerate tears be a sign of?
OA
How are knee ligament injuries graded?
1- sprain. Tears some fibres but total structure intact
2- partial tear with some fascicles disrupted
3- complete tear
Usualyly an MCL tear will heal well.
When might it be complicated?
If combined with ACL or PCL rupture.
What is the rule of thirds of ACL rupture?
1/3 will compensate and function well
1/3 will avoid instability by avoiding activities
1/3 will have frequent instability
What percent of ACL ruptures need reconstruction?
40%
What reconstruction is available for repair of ACL?
Autograft from patellar tendon or hamstrings
Allograft from the achilles
Synthetic graft
What is the rehab time for an ACL reconstruction?
3/12 to 12/12
How does an LCL affect the patient?
Relatively uncommon
Can cause varus and hyperextension
High incidence of fibular nerve palsy
What treatment is needed for an LCL?
Urgent (2-3 wk) repair then reconstruction
When does a PCL injury occur?
Direct blow to anterior tibia
What can occur with a knee dislocation?
Popliteal artery tear
Fibular nerve damage
Compartment syndrome
Who is more likely to get a patellar dislocation?
Females, adolescents with ligamentous laxity
How does a patellar dislocation occur?
Rapid turn or direct blow
What can be clinically seen with an extensor mechanism rupture?
Palpable gap
Unable to straight leg raise
What atraumatic cartilage defects exist?
Osteochondritis dissecans
OA
Why will only cartilage injuries which are full thickness heal?
Blood vessels are only after the tidemark. If the tear is above the tidemark it will not heal.
What kind of cartilage is present when healed?
Fibrocartilage.
Usual cartilige is hyaline
What is osteochondritis dissecans?
Where an area of knee loses its blood supply.
Bone can fragment off
What age group is osteochondritis most common in?
Adolescents
What surgical treatment can be given for osteochondritis?
If detached then can remove.
If detaching then can pin in place
What is cartilage regeneration?
Stem cells found within the bone and grown to produce new cartilage
How long will a cartilage regeneration last?
Around 5 years
What is the risk of multiple steroid injections with OA?
May accelerate the arthritic process
When would an osteotomy be a good idea for control of OA?
If heavy manual worker and needs 10 years to retire.
What is an osteotomy?
The arthritic bone is removed and replaced with another bit of bone
Why wouldn’t a TKR be given in painful OA?
If young then will wear out the new joint too quickly and the second TKR is never as good.
How long can a TKR last in older patients?
20 years
What are common presentations to GP regarding knee?
Anterior, localised pain Stiffness Swelling Giving way Deformity Loss of function
What must you always keep in mind regarding knee pain?
Could actually be pain from hip
What is Osgood-Schlatter’s disease?
Inflammation of patellar ligament at tibial tuberosity.
Most common in adolesents
What are the most common knee problems?
Ligament strain- most commonly medial collateral
Bursitis
OA
What kind of cartilage tear are you thinking if you hear a pop and develop a haemoarthrosis?
ACL
What is a chronic complaint with an ACL rupture?
Rotatory instability with giving way on turning
When would a complete knee dislocation occur?
All 4 ligaments torn
What is an extensor mechanism injury?
Rupture of patellar tendon or quadriceps tendon
What are predisposing factors to an extensor mechanism injury?
Tendonitis
Chronic steroid (ab)use
DM
RA
What direct does the patella dislocate?
Laterally
A valgus misaligment predisposes to OA of which part of the knee?
Lateral since valgus misalignment puts a bigger stress on lateral bones
