WK9 - Acute Knee and Below Knee Injuries Flashcards
Considerations of sports knee injuries.
- most common sports injury
- frequently misdiagnosed
- can lead to early arthritis
What is the immediate field management of knee (and other sporting) injuries?
-Effective on-field management requires systematic approach for injury recognition, response and referral
TOTAPS
* Talk
* Observe
* Touch
* Active movement
* Passive movement
* Skills
What is the management of knee injuries?
- rapid Ax
- rapid Tx
- rapid rehabilitation
^most athletes want RTP ASAP
What is the Hx for knee injuries?
Swelling
- immediately –> blood within joint, hemarthrosis
- in period after
Snap
- ACL? Any significant ligament injuries
Looking
- to orthopedic surgeon: hear knee locks and unlocks “came undone” –> mobility of the athlete
Give Way
- not just ligamentous rupture, could also refer to atrophied muscles causing knee to collapse
What to examine after checking Hx of knee injury?
- Leg exposed/bare
- Effusion (fluid within joint // may need to sweep hand back and forth to see where the fluid is)
- Tenderness
- ROM (pain, EXT/FLEX)
- Ligament and meniscal tests
What to look for considering tenderness during examination?
- pain (what areas?)
- checking along joint lines and along bones
- tenderness along MED joint line could point to MED joint pathology/meniscal tear
- tenderness of MED joint along collateral ligament line could also indicate ligament injury
What to look for considering ligament and meniscal during examination?
- tenderness
- manoeuvre into full FLEX and adding motion
-McMurrary’s Test –> palpable and audible clunk can indicate meniscal tear - placing strain on various ligaments and looking for laxity (ACL, PCL, MCL)
- shift test –> ACL, checking for shift in ROT attitude of tibia during loaded FLEX and EXT
List a few specific knee injuries.
- MED ligament tear (one of the most common)
- ACL
- PCL
- meniscal tear
- patella instability and dislocation
What is the cause and signs of MCL injuries?
Acute valgus force (distal limb away from body)
- knee in EXT, MED ligament torn, LAT compartment compressed
Signs of MED lig Tears
-Medial pain and swelling in region of medial ligament
-No significant effusion
*MCL sits just outside synovium thus blood doesn’t accumulate within joint
-Tender over MCL insertion on femur or tibia
*May have joint line tenderness – the line of MCL that is painful
-May have laxity on stressing
*Joint opening allows for classification
What are the classifications for MCL injuries?
I –> MJL opens <5mm
* Unlikely that significant damage has occurred
II –> MJL opens 5-10mm
* Partial disruption of fibers
* When opening up joint, there’s an end point to it
* Capacity for ligament to function well in future
III –> MJL opens >10mm
*When opening up joint, no end point
What is the Tx for MCL injuries?
I –> RICE, splint for pain
*Should be able to walk on leg, maybe have compression bandage
II –> Quad drills early
*RTP 4-6 weeks
*If not that severe, it is okay to RTP early as long as their muscles/knee are still in good condition
III –> look for other injuries
*Common to have g3 MCL with associated with ACL or even ACL, PCL
*For just MCL, occasionally may need surgery but rarely need surgical repair because it is difficult to repair
*Conservative treatment for MCL will work just as well as operative unless associated with other injuries
What is the cause of ACL tears?
side step, jumps, tackle
- puts high stress on ACL, when reaches shear stress limit
- tibia subluxes forward
Mya hear snap/pop
May feel knee “slip out of joint”
What are the signs of ACL tears?
-Knee swells quickly (<24h)
-hemarthrosis
*Big swollen knee after acute injury is 70% likely to have torn ACL
-Lack full extension (by a few degrees)
*Torn fibers of ACL have flipped into intercondylar notch and jammed it
How to test for ACL tear?
Lachman’s sign
*Knee bent to 15 degrees
*Pull forward on tibia, back on femur
*Look for translational movement
Pivot Shift Sign
*More complex test
*Patient relaxed
*Flex and extend knee with valgus force
What is the Tx for ACL injuries?
- RICE
- quad drills early
–> quads can atrophy very quickly - orthopedic Ax early on
What are the consequences of ACL tears?
Shorter term
*50% lose a meniscus in 3y
Once you lose meniscus, higher rate/risk of osteoarthrosis
ACL reconstruction reduces risk of meniscal loss to about 10% in 3y
Long term
*Osteoarthritis
What are the effects of ACL reconstruction? Consider long and short term.
Short term
*Restores stability
*protect menisci from damage
Longer term
*Prevent osteoarthritis? Does it really prevent?
What are the indications for ACL reconstruction?
-Most people
-Symptomatic instability
*Giving way because of the rupture
-Repairable meniscal tear with ruptured ACL
*Repair both together
*Just repairing meniscal tear invites higher failure rate of meniscal repair
-Young person with ACL tear
-Anybody intending to remain very active
*Athletes
*General population that wants mobility
What is the ACL reconstruction technique?
Arthroscopic surgery
*Hamstring – semitendinosus and gracilis
*Screw fixation
*Autograft vs allograft (auto is own patient’s tissue, allo is donor tissue)
Auto is preferred
How long for ACL rehabilitation and recovery? Consider results of the surgery.
*1 night in hospital
*2 weeks in brace on crutches then return for consultation before walking
*3-4 months before running
*7-9 months before RTP
Longer periods before RTP to decrease reinjury rates
Ensure dynamics and biomechanics are working well
Results
*95% stable in daily activities
*90% RTP
Not everybody goes back
*Arthritis – long term outcome
*Revision rate (require second surgery)
What are the characteristics of PCL injuries?
-Less common injury
-Rarely results in significant instability
-Strength program (conservative) instead of surgery
-2-3 months before RTP
-Signs are similar to ACL
*Use Lachman’s test, anterior draw test, posterior sag test
-Ensure no other capsular injuries
*Medial ligament
*Posteromedial
*Combination injuries may require surgery
-Hamstring reconstruction rare
-Potentially dangerous area
*Tibial attachment right on the back and top of tibia
*Artery and nerve running outside joint capsule
*Reason why surgery not best option unless very necessary
What considerations are made for PCL reconstruction?
- clear instability
- associated with other ligament tears
- only after good rehab has failed
- usually successful
What is the mechanisms for meniscal tears? What are the signs?
- twisting on planted foot
- ROT forces cause shear stress to meniscous
Signs
-Doesn’t have significant swelling
*Exceptions may be bucket handle tear
-Localized joint line tenderness
*Along meniscus
-Locking or giving way
-Meniscal stress tests
*Pushing knee into flexion with various degrees of rotation
*Produces pain at back of knee
-MRI scan 95% accurate
What are the types of meniscal tears?
- Vertical tear –> progress to bucket handle tear
- radial tear –> progress to parrot beak tear
- horizontal tear –> flap tear
*bucket handle –> can put tear back together
* radial tear –> disrupted fibres, hardest to put back together, considered the worst
What is the Tx for meniscal injuries?
Operative intervention, arthroscopy especially for younger athletes
*Meniscectomy Partial resection (removal)
6-8 weeks recovery
Create a smooth margin so weight-bearing does not cause pain
*Meniscal repair (preferred)
Recovery 2x of resection, 12-16w
First 4 weeks non-weight bearing in knee splint
Week 5-8, knee brace allows 0-90 degrees
*Avoid extreme movements (hyperflexion/extension) but allow strength building
–> After 8 weeks, agility training then another 4-6 weeks to get up to prior level
What is the mechanism and signs of patellar dislocation?
Females 10x more likely
Usually have an underlying predisposition
Mechanism
-Flexed knee under valgus loading (jumping)
Signs
-may stick out
-May reduce spontaneously
*Looks normal but swell afterwards
*Important to look at Hx/observation/patient description
-Lump visible on LAT side
*Patella does not naturally/usually displace MED ALWAYS LAT
-Knee flexed to about 20deg
-Tender MED side of patella
*When patella dislocates, tears MED patella retinaculum
-Knee swells rapidly
*Other cause of big swollen knee after injury (other one is ACL)
What is the Tx for patellar dislocation?
-May reduce with passive extension
*Eg if pick up leg while being carried off field
-Knee splint
*Only leave it on until they feel comfortable again
*Long term splinting is bad
-Should have early movement
-X-ray for loose fragment (or MRI)
*If a piece of patella gets knocked off during displacement
*Will need arthroscopic removal
-Commence quads drill early
What are the statistics for reinjury after patellar dislocation?
- 50% chance after single dislocation of having another one
- 90% chance of redislocation after 2nd one
What is patellar instability?
- realignment is effective
- tibial tubercle transfer –> move tibial tubercle (from LAT position) to change forces
–> align mechanism of patellofemoral joint
–> low rate of redislocation
What is the prevlaence ofl ower limb injuries below the knee?
1 in 5 players sustains an injury every season
- most common hamstrings, ankle, knees
- at least 1 previous injury/reduced lower limb function score has a significant increased risk of sustaining new injury of same kind during 8month follow-up period
*Important for us to RECOGNISE and REMOVE
What is the Ottawa ankle score?
OA Rules
- pain on dorsal side of 1 or both malleoli
- palpation pain at base of metatarsal 5
- palpation pain of navicular bone
-inability to walk at least 4 steps
- rule out fractures and reduce need for x-rays
Sensitivity –> 86-99%
specificity –> 25-46%
What is there to consider about the LAT side of the ankle in the Ottawa Ankle Scores?
- more POS than ANT, around where ligament attaches
- various attachments to one could cause periosteal disruptions and thus pain on palpation but may not be due to fracture
What are the Utrecht Ankle Rules?
pain with axial compression is similar to putting weight on foot –> get xray
- swelling
-inability to weight bear
- deformity, instability, crepitating
RULES
4 - deformity, instability, crepitating
2 - inability to weight bear, axial compression pain
2 - tibia palpation pain and swelling
1 - fibula palpation pain and swelling
1- Achilles tendon palpation pain and swelling
1 - base of 5th metatarsal
1 - haematoma/haemarthrosis
Age divided by 10
Radiography required if >8 when added up
Sensitivity = 59%
Specificity = 84%
What area do we also need to check following injuries to MED side of ankle?
LAT aspect of knee!
Maisonneuvre fracture (prox fibula)
- usually accompanies unstable ankle injury
–> force enters through ankle and travels up to fibular
- likely not weight-bearing, as it is a significant injury
What does the ATFL of the ankle do? Consider injury.
- controls AP draw, taut during PF (restrain against PF)
- primary restraint against pathologic PF
- 2 parts - 1 part is within synovium, usually does not heal well
- if there is no pain on palpation of ATFL, unlikely there is actue LAT ligament rupture
What is the role of the CFL in the ankle?
Calcaneofibular ligamnet
- runs below subtalar joint, holds subtalar joint
- controls inversion, taut in DF
What is the role of PTFL in ankle?
- comes into play with ankle dislocation
Does not have a lot to do with PF?
What is the prevalence of ankle injuries? Consider injury, signs and diagnosis.
-60% of patients with acute LAS have pain on level of medial malleolus
-40% of patients with acute LAS have pain over AITFL without rupture of ligament (anterior inferior tibiofibular ligament)
-Delayed physical examination (4-5 days) is more reliable than physical examination within 48 hours
*In terms of specificity and sensitivity in diagnosing
*Allow for everything to settle
-Only ~50% of individuals who have a LAS will seek medical attention for it
-40% of individuals who sustain LAS will develop chronic ankle instability (CAI) and may not be able to RTP
What is the ANT draw test?
-ATFL disrupted = excessive anterior movement compared to other side positive anterior draw test
-Forward translation of talar dome relative to tibia
*Could potentially be due to old injuries
-Compared to healthy ankle
-Combination with other tests allows for degree of laxity to be determined
*Eg. Prone anterior draw test
What to do during delayed examination of ankle injuries?
-Positive anterior drawer test + pain on palpation of ATFL and hematoma discoloration
*98% Sensitivity
*84% Specificity
-May not need expensive tests like MRI, CT, x-ray etc
-Ultrasonography has similar sensitivity (92%) but lacks specificity (64%) compared with delayed examination
What is the healing process of ankle injuries? Consider duration as well.
Inflammatory phase (immediate)
Proliferative (6WKs-3months)
Remodelling phase (up to 1y post-trauma)
What is the management of ankle injuries?
- PRICE/RICE/POLICE
- bracing // casting
What is the recommendation of PRICE/RICE/POLICE managment?
*No evidence that RICE alone/cryotherapy/compression therapy alone has any positive influence on pain, swelling or patient function
-No role for RICE alone in treatment of acute LAS
*Joint cooling does not adversely affect muscle reaction time or muscle amplitude provided you don’t leave it on too long
*Cooling doesn’t affect other specific components of neuromuscular control such as joint position sense
*Ice can be applied before ankle rehab without adversely affecting dynamic control
-Effects should be limited to 10 minute applications of either wet-ice application or cold-water immersion
What did the Lancet 2019 study find on bracing vs casting?
Lancet 2019 study on simple ankle strains
*The ones who did the best were those in plaster casts
-Min. 4wks in lower leg cast following acute LAS = less optimal outcomes compared with functional support and Ex strategies for 4-6wks
*Maybe max. 10-14 days immobilization, allow other professionals to determine recovery course of action
-Use lace-up or semi-rigid ankle brace = better outcomes compared to other functional types of treatment like sports tape or kinesiotape
*Good for immobilization and preventing reinjury
What is the difference between Copers and Non-Copers in chronic ankle instability?
*Copers are those who suffered ankle sprains and have no residual symptoms
*Non-copers are those who suffer from CAI
What are the implications of chronic ankle instability?
- ankle corrects for small errors in faulty foot placement
- hip corrects for larger errors in faulty foot placement
- poor hip ADB/errors in hip mechanics will alter the way you land and increase likelihood of stress and inversion –> CAI
–> shows how instability or problems at 1 level can affect the ankle
–> injury at 1 level –> can’t control at subtalar joint
–> need to work harder at hip but if can’t control at hip then leads to more ankle instability
What is the difference between Copers and Non Copers: people with CAI vs healthy
- ANT tibialis works less than half compared to healthy people
- CAI people overuse the peroneus longus, MED gastroc and glute medius muscles compared to healthy people
** fibularis longus compensating for lack of ankle stability –> LAT compartment pain, fibularis longus tendonitis
** if muscles are not activating at the right time (e.g. too early in the swing phase) –> potentially more fatigue-aggravated ankle instability/laxity
^^ could be normalised with ankle bracing or taping
What are the impacts of landing movements for ankle injuries?
-Achieving an equilibrium between the combined goals of stopping downward velocity of body and preventing collapse of lower extremity
-Increase hip flexion is one component of a preparatory strategy for CAI group to attempt to reduce risk of impact
-Eg jumping and landing on soft surface –> bend more to compensate for lack of ankle instability and balance
-Even if they don’t have pain but you notice them doing ^, may indicate CAI
What are less common lower limb injuries below the knee?
LAT/Talar Dome Injuries (Mortise and Tenon Joint)
“OCD” fracture
* inversion with PF or atraumatic
- small piece that wasn’t fused on and is jamming/getting caught
- if people complain ankle is giving way but do not have hypermobility/ligamentous laxity, potentially have OCD
What are the common movements that cause Lateral/Talar Dome Injuries?
- inversion with PF or atraumatic (MED side)
- inversion with DF
- forced PF jamming (people who are consistently “on pointe”
- point tenderness over LAT process (ANT and INF to the LAT malleolus) due to fracturing
- fracture at neck of talus
- fracture of ANT calcaneal process (articulates with cuboid) - not common
- Jones fracture
- overuse traction apophysitis
Why are people who are consistently “on pointe” at risk of lateral/talar dome injuries?
*Tenderness to deep palpation anterior to Achille’s tendon over posterolateral talus instead of over Achille’s
*10% of population will experience, may be asymptomatic until plantarflexion
*Plantar flexion may reproduce pain
What sport is point tenderness over LAT process related to?
“Snowboarders ankle” due to forces going through the area in the common snowboarding position
- may require surgical incision if there is non-union
How does the fracture of the ANT calcaneal process (where it articulates with cuboid)?
Chopart Joint
-Between talonavicular and calcaneocuboid midfoot joint/Bifurcate joint between calcaneus, cuboid and navicular ??
-Part of joint process that holds up arch
-Many ligaments in this area
-Dorsal ligaments between cuboid and calcaneus
If ligaments are stretched, could cause disruption and an avulsion fracture
If ligaments are compressed, could cause compression fracture – fracture depends on joint movement
^ may be good to brace
What are the ligaments of the Chopart Joint?
- TN - talonavicular (top bony structure)
- bifurcate ligament (middle)
- DCC - Dorsal Calcaneocuboid Ligament (slightly below bifurcate ligament
What is the Jones Fracture?
*Involves 4th and 5th metatarsal articulation
*Tendon of fibularis tertius and brevis are pulling in opposing directions
*Typically a stress fracture leading to a fracture
*If you miss this fracture, little chance of healing well
*Vascular considerations
-Zone 1 – avulsion not a big deal
-Zone 2 – articulating btw 4th and 5th, differential forces, poor blood supply, don’t heal very well
-Zone 3 – likely overuse, will break
What is overuse traction apophysitis?
*Growth plate and avulsion in different directions
-Avulsion horizontal but growth plate is vertical
*Traction apophysitis of 5th MT
*Usually no surgical options, just conservative in boot
*Can take some time to show evidence of healing
-Clinical signs but radiologically not filled in yet
The medial ankle requires a complex set of ligament to restrain multiple different movements. T or F
T!
MED collateral (deltoid) ligament attaches to the POS tibiotalar, tibiocalcaneal, tibionavicular and ANT tibiotalar
When are the medial collateral (deltoid) ligaments activated?
- ANT deltoid under max. tension when PF
- mid portion of deltoid tension when hyperpronated
- EXT ROT = deep deltoid ligament
- ABD/Eversion = superficial deltoid ligament
Where do medial ankle ligaments attach to?
tibia down to talus, navicular and sustentaculum tali
spring ligament ST to navicular –> sitting underneath, supporting talus/talonavicular head
* creates socket and support for head of talus
* most essential ligament in maintaining MED longitudinal arch
List the ligaments from superior to inferior of the MED ankle
- Spring ligament
- Short plantar ligament
- long plantar ligament
- plantar aponeurosis
List the function of the deltoid ligament?
- Provide med stability to tibiotalar joint by providing a firm fixation between tibia and talus
- Prevent talus shifting into a valgus position or to move anterolaterally or externally rotate
- Prevent talus (med) shifting more than 2mm laterally, even if lat structures aren’t in place
- Pos tibiotalar ligament restricts int rot of talus (deep fibers)
- Sequential cutting of superficial ligament still results in ankle stability
- Gross instability of ankle develops if deeper fibers of ligaments are cut (surgically)
- Difficult to surgically repair
What are the MED ankle considerations of the deltoid ligament?
- Without deltoid ligament forces go through ankle and fracture fibula (Maisonneuve)
- Isolated deltoid ligament injuries are rare (3-4%)
- Usually with deltoid involved, other structures are injured as well
What did a study on medial ankles find?
*47 ankles with chronic lateral ankle instability with no medial ankle pain, deltoid ligament injuries were observed in 72% of ankles
*In subgroup of patients with MRI evidence of lateral ligament injury, incidence of deltoid injury was 35%
signs: tenderness at MED gutter of ankle joint
How to test medial ankle function?
-Movement into supination-external rotation
-Eversion-pronation
^ stress deltoid ligament
-Single heel raise is not indicative or diagnostic for deltoid ligament (test for tibialis posterior or lateral ligaments)
What to further test for If medial pain is more upwards instead of the ‘gutter’, more likely that tibialis posterior is affected?
Think about the line around the pos side of the med ankle bone!!
-Posterior tibial tendonitis
*Unsteady gait
*Difficulty pointing toes inwards
*Failed heel raise
Test for ^:
-Squeeze tennis ball between medial ankles and raise up on toes
-From valgus heel position to varus
-Activation of tibialis posterior
^ excess bit of bone which can be a source of injury, kind of sticks to navicular and can be disrupted during injury pain over navicular
What is the mechanism of a high ankle sprain/syndesmotic sprain?
-Planted foot, pronating + externally rotating then blow at knee
-Rotational forces at mortise and tenon joint – major stress
- EXT ROT mechanisms
- longer recovery
- occurs in sports such as Hockey and Skin
What happens to the talus in DF and PF?
DF: talus snug in joint between malleoli and against trochlear surface
PF: not snug
Implications of high ankle sprain?
-Widening the ankle mortise by 1mm decreases the contact area of tibiotalar by 42% instability and early arthritis (severe)
*Bracing may be a good idea because every time you walk, the tibio-fibular joint springs apart and could cause it to heal in a widened position, leading to instability after recovery
How to test for a high ankle sprain?
External rotation test
* Place knee at 90 degrees with ankle at neutral
* Apply an external rotation force
Squeeze test
* Compress proximal tibia and fibula
* Positive test occurs at level of ankle joint
* Pain more proximally should alert suspicion of proximal fibula fracture
Crossover test
* Pressure applied to externally rotate ankle
Patient pushes down on foot
* Pain will be felt with disruption of syndesmosis (not seen with LAS)
* Patient lead, will stop if pain is too bad
How to treat high ankle sprains?
-Bracing
-Tight-rope (surgical correction)
*Rope holding pieces together
*Tighten rope until it can’t be tightened anymore
*Rope will break eventually but scar tissue should be able to hold it together
-Screw
*But will need to have surgery again to come out, not preferred because ankle should have some degree of mobility
What is pain below the knee and above the ankle called? List out the characteristics for acute and chronic.
Compartment syndrome
Acute
* Direct trauma or fracture
* Compromise neurovascular bundles
Muscles may not be receiving adequate perfusion
Irreversible damage
* Not very common
* Signs:
Pain and swelling in shin, numbness in foot and toes
Chronic
* Fascia thickening
Continuous running can cause muscle hypertrophy but compartment doesn’t expand as well, trigger stimulus to fascia (muscle attaches to it) can cause fascia to thicken
Can be congenitally thicker
* Pressure can decrease after rest
* Exertional compartment syndrome more likely to happen on anterior side
Back of leg is less contained than anterior
How to test for compartment syndrome?
Important:
- Ask about patient history
* Friis’ example – creatine caused increase in muscle size due to water retention causing chronic compartment syndrome
Tests:
- Pressure testing
What is the Tx for compartment syndrome?
Fasciotomy
*Pressure can build up again
*May do fasciectomy instead
Removes attachment site of anterior compartment muscles
Reduces recruitment ability of these muscles
What is the Tx for compartment syndrome?
Fasciotomy
*Pressure can build up again
*May do fasciectomy instead
Removes attachment site of anterior compartment muscles
Reduces recruitment ability of these muscles
What is ANT cortical stress fracture and the mechanism of it?
-Pain when tapping over the shin
-Do not heal properly and can take a very long time
Mechanism:
-Tibial Vara
-Overstriding when running
*Contact/lead foot in front of center of mass
-Others
What is ANT cortical stress fracture and the mechanism of it?
-Pain when tapping over the shin
-Do not heal properly and can take a very long time
Mechanism:
-Tibial Vara
-Overstriding when running
*Contact/lead foot in front of center of mass
-Others
What is the Tx or solution ot ANT cortical stress fractures?
-Change technique for running
-Center of mass over the foot
-Forefoot landing so less forces going through heel
*Reduce stride length, increase step rate
-Nail
What are fibular stress fractures?
-Direct trauma to lateral calf
-Initial x-rays normal
-Torsional stress aggravates periosteal damage
*Particularly in jumping sports
-Serial radiology may be necessary
-Early rest for better long term results
-Presents/diagnosed as calf strain or peroneal tendonitis (associated with lateral ankle ligament injury)
MRI image of fibular stress fracture. Which side is the fracture located?
L (always lateral side of calf)
If you don’t stop torsional forces going through fibular then it will progress to a full fracture.
