Knee Problems Flashcards
What is a meniscus?
A crescent-shaped piece of fibrocartilage that partially divides some synovial joints to provide stability
There are 2 - medial is semi-circular and lateral is almost circular
Describe the structure of a meniscus?
Type 1 collagen - fibrocartilage
Contain both radial and circumferential fibres
Describe the vasculature of a meniscus? Specifically the knee
Inf Medial geniculate & Lateral geniculate arteries –> Perimeniscal capillary plexus –> Circumferential & penetrating radial vessels.
Further from the periphery (where the plexus is) it gets less vascular, tears here won’t heal even if you stitch them back together
What are the most common acute knee problems?
- Fracture
- Acute on Chronic Degenerative disorders
- Meniscal injury
- Ligament injury
- Tendon injury
What questions are important to the history in the context of a knee injury?
1) Environment i.e. specific sport, workplace & activity at moment of injury?
2) Energy of injury
3) Systemic Symptoms
4) Chronology incl. onset and previous events
5) Hear or feel a pop/crack?
6) Swelling & how early?
What does early swelling mean?
Probably Haemarthrosis i.e. blood in the joint suggesting:
- Certain meniscal tears
- Tearing certain vascularized ligaments
- Broken into the bone
What would you check for on exam of an injured knee?
- Scars, bruising or swelling
- Joint line irregularity
- Effusion
- Crepitus
- Heat
- Tenderness
- Lumps/defects
- Movement, both passive and active
What tests can be used for knee injuries?
X-ray
US
MRI
What would an X-ray detect?
Fracture
Loose Body
Ligament Avulsion
Osteochondrol defect (both bone/cartilage torn off)
Degenerative e.g. OA
Lipohaemarthrosis due to fracture
What would an US detect?
Tendon Rupture
Meniscal tears
Swelling
Cysts
Young sporty patient describes twisting their knee and hearing a painful “squelch”.
Its painful to weight bear and some time later began to swell.
On exam the knee is locked i.e. can’t extend?
Characteristic of a meniscal tear
A twisting motion along with slow swelling and the locked knee are typical
Patient describes landing after a jump, changing direction and hearing a pop followed by swelling of their knee.
They can weight bear but its painful?
ACL tear
Sudden direction changes with forward momentum such as stopping suddenly or landing a jump along with rotation cause ACL tear.
Being highly vascularised this tear causes quick swelling
Patient presents with sharp pain on the lateral knee along with bruising. They say they heard a crack?
Lateral Collateral Ligament Tear
Sharp lateralised pain, feeling a crack and bruising with no effusion is characteristic of a collateral ligament tear.
Because tearing the ligament tears the capsule the effusion leaks into the surrounding tissues causing bruising and none/minimal effusion
When would we consider surgical therapy for a knee injury?
- Conservative Rx fails
- Work or sporting demands
- Daily activity difficulties
- Preventing further injury
- Preventing falls
What types of repair are there for meniscal tears?
- Meniscal repair, best technique is the All-inside technique
- Partial meniscectomy
- Meniscal Transplant
