The Bone School

Anatomy

Layers of the medial knee

Layer 1

- sartorius and sartorius fascia

Layer 2

- superficial MCL

- posterior oblique ligament

Layer 3

- deep MCL (meniscofemoral and meniscotibial ligament)

- posteromedial capsule 

MCL

Origin

- 3 mm proximal and 5 mm posterior to the epicondyle

Definition

Hoffa's syndrome

- impingement of the fat pad with knee ROM

Epidemiology

Rare

Diagnosis of exclusion

Theory

May be more prevalent in patients with intact ligamentum mucosum

Diagnosis

Hoffa's sign

- apply pressure to fat pad each side of patella tendon with knee in flexion

- extend knee

Approaches

Medial Parapatellar

Medial

Lateral

Posterior

Modified Posterior

Medial Parapatellar Approach

Indications

Synovectomy 

Patellectomy 

TKR

Technique

Anatomy / Biochemistry

Constituents of cartilage

Indications for Repair

Only 20% repairable

1. Red / Red longitudinal tear

- outer 3mm / meniscocapsular junction

DDx

Baker's Cyst

Popliteal Anerysm

Soft tissue sarcoma

Osteosarcoma / Parosteal OS

Hemangioma / AVM

Note:

Always do xray for calcification

A Bakers cyst / aneurysm can be calcified

Source

OCD

OA - Osteophytes

Meniscus

Symptoms

Pain

Locking

Clicking

Can cause chondral damage

Xray

OA Loose Bodies

Definition

Patellar Tendinitis

Epidemiology

Most common in athletes

- especially if involved in running, jumping and kicking

- over use injury

Basketball players

Aetiology

Chronic overload v inferior patella impingement

Schmidt et al Am J Sports Med

- dynamic MRI in patients with jumper's knee v controls

- no evidence of impingemnt

Principles

Foot

A little equinus is better than calcaneus

A little valgus is better than varus

A little varus is better than severe valgus

TA lengthening is most over used operation in CP

Knee

A little knee flexion is better than recurvatum

Knees

Problems

Tight hamstrings 

Plica 

Jumper's knee / Tendonitis

Bursitis

- prepatellar most common

- Pes anserinus 

Excessive Lateral Pressure Syndrome / Patella Tilt

Hoffa's Disease / Fat Pad Syndrome

ITB Syndrome

RSD

Others

- RA