What is the MC knee injury in service members?
Meniscal tears are 10x more common
Which meniscus is most commonly torn?
Medial meniscus
Medial meniscus shape and what is it attached to?
It is semilunar and adherent to MCL
Shape and location of the lateral meniscus?
Circular
Covers more of the tibia
What is the purpose of a meniscus?
Distributes the load of the joint via circumferential or hoop stress
How much does lateral meniscus decrease compartment loads by>?
70%
Medial meniscus decreases compartment loads by___?
50%
Common tears of meniscus?
Vertical longitudinal (moon in the middle)
Vertical radial (a cut)
Horizontal (wear on the inside of the c)
Oblique (oblique cut)
Complex/degenerative (shit show)
Slide 8
What is the effect of a meniscal tear?
It disrupts the mechanics of the knee, leading to degenerative arthritis
Blood supply in meniscuses?
The more peripheral the higher the blood supply
The higher the blood supply the higher the chance of of healing
MOA for meniscus tear?
Usually pivot or twist
Meniscus warning signs
Joint line tenderness of medial or lateral side of knee
Pains worsens w twisting or squatting
Mechanical symptoms (locking, catching and popping)
Effusion >12hrs (slow leak)
PE for meniscal tear?
Joint line tenderness
Decreased ROM (esp w locked knee)
Special tests for meniscus tear?
McMurrays
Thessaly
Apley’s
Pt has a displaced “bucket handle” meniscal tear?
Surgery ASAP
What do radiographs show?
Eval for loose bodies/bone fragments
What grades of meniscus tear are visible on arthroscopy?
III and IV
You’re getting surgery
You get a meniscus tear and it gets fixed (or doesnt) what do you win?
Osteoarthritis will develop
Who should not get surgery?
Conservitavie management for:
- 40+ w pain but no mechanical symptoms
- degenerative tears and/or middle 1/3 (avascular)
Who should get surgery?
Young population Tears between 1 and 4cm Vertical tear Red-red tears Meniscal root tear Failure of nonopp Bucket handle/locked knee
We decide not to get surgery how do we treat your meniscal tear?
The same as any other musculoskeletal inj
Acute Rehab
Subacute rehab
Bracing
Back to life
96% of the time what are the surgeons doing for meniscus tears?
Debride
Only 4% repair
(Civilians)
How does the military handle surgery for meniscal tears?
The military does many more repairs than the civilian sector does
What meniscus tears get referred?
Trauma, mechanical symptoms or instability
Failed non-opp
All bucket handle tears
Young people
What is an OCD?
Osteochondritis dissecans : osteonecrosis of subchondral bone
Usually occurs in the knee but not always
MC location for OCD?
Posterolateral side of the medial femoral condyle
What causes OCD?
Repetitive small stress to the subchondral bone that disrupts the blood supply to an area of bone
Osteonecrotic bone separates
Shear forces fracture the articular surface
What happens to the osteonecrotic fragment once it breaks free?
It can become a loose body in the joint
Clinical presentation of OCD?
Gradual onset of knee pain
Knee effusion and catching or locking symptoms
MC site for OCD?
Medial femoral condyle, palpated with the knee flexed at 90*
What is the best x-ray to view OCD?
Tunnel and lateral views
What is the treatment goal for OCD?
Reduce shear forces allowing new bone formation
Requires creeping substitution of new bone
How well does surgery work for OCD?
It may slow down the damage, but youre probably eventually getting a new knee
Does nonoperative tx work?
If the cartilage is still intact
however…
Doesnt really work after skeletal maturity
What do the surgeons do for the bone with OCD?
They will do microfracture
Or drilling
Can also do autograft (but thats not in the slides)
Another option is temporary internal fixation (peads)
Does the physis matter?
Yes if the physis is still open the prognosis for healing is significantly higher (kids)
What is a plica?
A normal fold in the synovium
There are 5 potential places for them but most are asymptomatic
Where is the medial plica?
Extends from the medial joint capsule to the medial anterior fat pad
How does plica present?
It becomes inflammed or thickened from trauma or overuse
Aching over anterior or anteromedial aspec of knee
Painful snapping or popping
Buckling or instability may occur
Where are most symptomatic plicas?
Usually the medial plica
How stable are plicas?
Though buckling or sense of instability may occur the true giving way, locking or obvious effusion is uncommon
Can you palpate plica?
Sometimes you can palpate a “thickened band” with the knee flexed
Does radiology show anything?
They are usually normal but you get them to r/o other stuff (i.e. to bill insurance)
Management of plica?
Decrease inflammation and thickening
NSAIDS or Tylenol
Modify activities
Local anesthetic and corticosteroid
What is diagnostic and therapeutic of plica?
Injection of local anesthetic and corticosteroid into the plica
Surgery for plica?
Not usually but in extreme cases you can do an arthroscopic resection
What is bipartite patella?
One or more secondary centers of ossification fail to fuse
Mc the superolateral pole
Basically 2 patellas
How are bipartite patellas usually diagnosed?
Typically its an incidental finding
Differentiating bipartite patella from a fx?
Remember fractures dont have smooth edges
PE for bipartite patella?
You may feel a prominence over the superolateral pole of the patella
5 bursal sacks of the knee?
- Pre-patellar
- Supra-patellar
- Infra-patellar
- Pes anserine
- Iliotibial tract
What causes bursitis?
Chronic friction causes thickening of the synovial lining and subsequent excessive fluid formation -> localized edema and pain
Prepatella bursa aka?
Housemaids knee
Bursitis presentations?
Inflamed (bursitis)
Infected (septic bursitis)
MC infection agent in prepatellar bursitis?
Staph aureus
Where is the prepatellar bursa?
In front of the patella
Where is the suprapatellar bursa?
Between anterior surface of lower part of femur and the deep surface of the quadriceps femoris
Above the knee
Where is the infrapatellar bursa?
Between the upper part of the tibia and patellar ligament
Below the knee
Where is the pes anserinus bursa?
Under the insertion site of the sartorius, gracilis, and semitendinosus muscles on the medial flare of the tibia just below the tibial plateau
Who gets pes anserine bursitis?
Usually its pts w early osteoarthritis in the medial compartment
What causes iliotibial tract bursitis?
Repetitive flexion and movement of the knee inflames it
Also causes iliotibial band friction syndrome
How does bursitis present?
At first pain w activity
Gets worse after being sedentary
Localized swelling over structure
What is pes anserine bursitis often confused with?
Medial meniscal pain
But pes anserine is distal to the joint line
Difference infected bursitis from septic joint arthritis?
Septic knee arthritis has:
- intense pain
- large effusion
- erythema
- guarding w motion
- limited ROM
- low grade fever
Infected bursitis is usually not super painful or erythematous
Which bursitis can cause numbness distal to the patella?
Pes anserine bursa can compress the saphenous nerve and its infrapetellar branch
Radiographs presentation of bursitis vs septic arthritis?
Anterior soft-tissue swelling w prepatellar bursitis
Septic arthritis has an effusion most compressed in the suprapatellar pouch
What needs to be done with suspected septc bursitis?
The slides say aspirate but dont stick the needle into the erythematous skin
He says cut them to drain and take sample
What labs does the sample for septic bursitis need?
Gram stain
Culture
Crystal analysis
Synovial fluid analysis
Treatment for bursitis?
NSAIDS, RICE, stretching
Corticosteroid
Ultrasound phonophoresis (prob wont help)
Surgery for bursitis?
Rarely done but the slides say you can do a needle decompression or a surgical drainage
He says dont do this
Abx for bursitis?
Early onset septic bursitis can be managed with oral abx
More sever gets IV abx
What bursitis gets referred?
Dont respond to tx
Recurrent pes anserine bursitis
Prepatellar bursa that are recurrent
What does a rupture of the quad or patella tendon result in?
It disrupts the extensor mechanism of the knee
What causes quad and patella ruptures?
Trauma
Usually a fall or MVA
Who usually gets a quad or patella ruptures?
Men 40-60 (weekend warriors)
Prolonged use of fluoroquinolones
Presentation of quad and patella rupture?
Significant pain after acute injury
Limited walking
(Can ambulate w incomplete rupture)
PE for quad and patella rupture?
Large effusion
Palpable defect
Fx is obvious but rupture may be harder to find
What is the key to diagnosis for quad and patella ruptures?
Patients inability to extend the knee against gravity or perform a straight leg raise
Diagnostic tests for quad and patella ruptures?
Plain radiographs
(Patella is lower or higher than it should be)
MRI can confirm rupture of the tendon but is rarely necissary
Patella alta and patella baja?
Patella alta: high riding patella
Patella baja: low riding patella
Blumensaat line?
Line drawn along the roof of the intercondylar notch of the femur as seen on lateral radiograph of the knee joint
Do we need to fix quad and patella ruptures?
Unless you surgically fix this they will become disabled
Delay in tx is makes the outcome much worse
What do quad and patella ruptures get? (he never gives these to anyone else)
Knee immobilizer
Clinical triad for quad and patella rupture?
- Inability to actively extend knee
- Patella alta/baja
- Palpable defect
How fast do they need surgery?
With in 1 week
I awaken.
I consume oxygen, then bacon eggs and black coffee.
Then my wife
Then bacon
Nick offerman