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? [4]
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
How do we treat a ACL tear?
ACL rehab first
ACL reconstruction if needed
How do we treat an osteochondral injury?
- Debridement
- Reattach fragment
- Remove loose bodies
- Microfracture chrondroplasty
- ACI
What is Autologous chondrocyte implantation
Treatment for osteochondral injury
It involves growing cartilage from stem cells that can be implanted onto the injured area to regrow damaged tissue
What non-surgical treatments do we have for knee injuries?
Physio
Analgesia
Swelling reduction
ACL rupture features [2]
2 clinical tests
Crack, pop sound
Rapid swelling
Anterior drawer test
Lachman’s test
PCL rupture mechanism [2]
Hyperextension
Flexed knee hitting dashboard in RTA
Collateral ligaments features [3]
Bruising
Crack
Minimal swelling
Meniscal tear [3]
Clinical test
Delayed knee swelling
Squelch
Joint locks
Thessaly’s test
Knee Osteoarthritis [4]
> 50, overweight
Intermittent swelling
Crepitus
Limited ROM
What are occupations are these associated with and what is the difference in the presentation of knee pain:
Infrapatellar bursitis
Prepatellar bursitis
Infrapatellar bursitis - Clergyman's knee - Associated with kneeling Prepatellar bursitis - Housemaid-s knee - Associated with upright kneeling
Chondromalacia patellae
Ax
Ep
Pain characteristic
Ax: Softening of the cartilage of the patella
Ep: Common in teenage girls
Characteristically anterior knee pain on walking up and down stairs and rising from prolonged sitting
Osteochondritis dissecans
Pain after exercise
Intermittent swelling and locking
