Collateral Ligaments - KaNee Flashcards
What is the main way the ACL gets injured?
Through non-contact injuries
- usually a combination of hyperextension and valgus
What is the function of the ACL?
as the primary stopper to anterior movement of the tibia on the femur
secondary stopper of IR and ER of a NWB knee
What are the subjective findings regarding ACL injuries?
- women are 2-8x more at risk (!!)
- twisting or hyperextion as a mechanism of injury
- that popping or giving out feeling
- pain and onset dysfunction
- instability of the affected knee and can’t walk w/o assistance
- swelling right away (acute hemarthosis)
What is seen in the objective findings for ACL?
- increased swelling
- pain
- (+) anterior stability tests
- other knee structures are affected
What are the special tests conducted for ACLs?
Anterior drawer (Sn = 0.41 / Sp = 0.95)
Lachman (Sn = 0.82 / Sp = 0.97)
Pivot shift (Sn = 0.82 / Sp = 0.98)
Lelli’s
What is the gold standard for ACL special test?
The lachman’s test with the most sensitivity for acute ACL rupture
- (+) in 80% of nonanesthetized pts and 100% in anesthetized
What is the difference between an intact vs sprained ligament?
intact = abrupt and firm end-feel
sprained = soft or distinct end feel depending on the injury
What is the typical prognosis of an ACL tear?
Usually has other structures that are affected
- a post-op = 8-12 months for return to activity
What is the process of ACL reconstruction surgery?
It doesn’t fix the damanged/torn ligament but creates a new ligament using other tissues in the leg
can use their autograft or allograft
What is an autograft?
using own tissue which is usually, patellar tendon, hammies and quad tendon
What is an allograft?
using a tissue from a cadaver
What are the pros of allografts?
- lack of harvest morbidity
- less trauma and quicker surgery (due to less cutting)
- decreased post-op pain
- easier and early rehab
- sizing limits
What are the cons for allographs?
slower rate of biologic adaptation
longer inflammatory response
be able to “stretch”
slower revascularization and recellularization
What is the biggest problem for allographs?
HIGH fail rate (~ 25%) in youth
What are the usually load failures for native and autographs for ACL reconstruction?
Native = 1725 to 2160 N
Hammies = 2640 N
Patellar = 1580 N
Quads = 2185 N
Patellar -> Quads -> Hammies (strongest)
What is the overall graft failure rate?
11%
- the graft choice has no effect on the failure rate
What is the contralateral ACL injury rate?
13%
- possible compensations and just the worse luck ever
What are the major goals of rehab for ACL-injuries?
get good functional stability
bring back muscle swoleness
return to functional level
↓ the possibility for re-injury
using proper techniques like closed and open chain for proper rehab and progression
What is the most important movement
factors for ACL recovery?
getting full knee extension and good quad activation
What is the “general” time frame for ACL?
most people agree on a minimum of 6 months before getting back out there
the assumption is around 7-10 months with around a year recovery
4-5 months is jogging :)
What is the concern for return to sports for ACL injuries?
81% = return to some sport
65% = pre-injury level
55% = back to competitive sports
the risk of the second ACL is GREATER in both knees BUT more likely to happen on the opposite side :0
What is the main characteristic that differentiates the PCL from the ACL?
THAT BIH STRONG AS HELL
- the strongest and largest intra-articular ligament in the human knee
- it usually is either a stretch or complete rupture
What is the function of the PCL?
Primary stopper for posterior translation of the tibia onto the femur
How prevalent is a PCL injury?
less common than ACLs
- 3% of OP knee injuries
- 38% of acute traumatic knee hemarthroses
- 95% happens with other injuries (how bad the causes are for this thang)
What is the mechanism of injury for PCL?
“dashboard injury” = force towards posterior on the anterior surface of the tibia with knees flexed
or
blow to anterior tibia or fall onto the knee w/ PF
What sport has the highest incidence of PCL tears?
Football (Lamar Jackson)
Soccer
Rugby
Skiing
What are the clinical sx seen for PCL injuries?
effusion in 24hrs
limited ROm (10-20deg of restriction = pain)
Pain and instability w/ WB
What are the special tests for the PCL?
Posterior drawer (most sensitive)
Sag sign
What is the Sag sign?
No injury = the tibial plateau woll be 1cm in front of the femoral condyles
with the sag sign, that thang is DROPPY
- the tibia will be in a posterior position
What is the treatment for PCL injuries?
Most need surgical reconstruction
- most return to sports in ~9-12 months
What is more commonly injured between the LCL and MCL?
MCL is more commonly injured
- usually by itself or can have an added meniscus problem or even PCL issue
What is the subjective findings found in collateral ligaments sprain?
localized swelling or stiffness
either medial or lateral pain and tenderness
most are able to walk after an injury
What are the objective findings of an MCL?
tender along the entire course
- specific tenderness at the most proximal or distal attachment of the MCL = avulsion
can palpate quite clearly in knee flexion
What are the objective findings of an LCL?
anywhere where it runs along its attachment and origin
Can palpate quite clearly in a figure four position
What is the special test for the LCL?
Varus stress test
1. test at full extension
2. 30 deg of flexion
30 deg of flexion helps to relax the cruciate ligaments and posterior capsule
What is the special test for MCL?
Valgus stress test
1. test at full extension
2. 30 deg of flexion
What does a laxity in full extension in both MCL and PCL stress test indicate?
Shows a more extensive injury that might have ACL and/or PCL injuries :0
What is the function of the MCL?
prevents valgus (UwU) movement
What is the mechanism of injury for MCL injuries?
Since its common in contact sports:
- hit on the outside of the knee with the foot planted
- associated injuries are common which is also dependent on how bad it is
What are the sx for MCL injuries?
- pain over medial knee
- gets worse in flexion/extension of the knee
- pain can be constant or present during moving only
- feeling of unstable
- soft tissue swelling
What is indicated for a grade 1 MCL?
- tenderness on the medial femoral condyle or medial plateu
- min swelling
- pain but no laxity on valgus stress test @ 30 deg
What is indicated by a grade 2 MCL injury?
- specific tenderness @ the MCL
- mild to mod swelling and pain
- laxity on valgus stress test
for just MCL, knee should be stable during full extension stress test
What is indicated by a grade 3 MCL injury?
- tender over MCL
- LOTS of laxity on valgus stress w/o a stop
- if its that bad - usually has laxity in full extension as well
- ↓ pain = damange to nociceptive fibers
What structure is associated with a grade 3 MCL?
rarely includes the medial meniscus but instead - LCL because of the mechanism
= creating a compressing and shear of lateral compartment
What is indicated in the imaging for MCL?
ruling out fractures
MRI will show other involved structures or ensure the dx
What is the prognosis for a grade 1 MCL injury?
around 10 days
What is the prognosis for a grade 2 MCL injury?
around 3 to 4 weeks for a low end
What is the prognosis for a grade 3 MCL injury?
around 6-8 weeks
What is the assumed treatment theme for MCL recovery?
- because of the great blood supply, recovery for grade 3s can be nonsurgical
- intially, will focus on controlling that knee edema while ↑ ROM and quad strength
- area of injury on the MCL = determines where to start exercises
- Fast implementation of the stationary bike
