anatomy

Definition

Bunion

- medial prominence of head of 1st MT

Hallux Valgus

- medial deviation 1st MT

- lateral deviation of great toe

Anatomy

Metatarsal head

- has 2 grooves separating ridge (cristae)

Anatomy

3 facets

1.  Posterior facet (STJ)

2.  Middle facet (sustenaculum tali)

3.  Anterior facet (on distal medial aspect)

Anterior process 

- forms calcaneocuboid (CCJ) articulation

Thalamic portion 

- under lateral process talus

Tuberosities

Posterior tuberosity 

- posterior process / T Achilles attachment

Epidemiology

Incidence isolated deltoid ligament injury 2.5%

Anatomy

Strong fan-shaped structure 

- composed of a deep and superficial layer

Superficial layer 

- inserts as one continuous structure 

- navicular anteriorly, spring ligament (calcaneonavicular), sustentaculum, and calcaneum 

- measures 10 mm wide at its origin and 2 to 3 mm thick

Incidence

1 - 2 %

Anatomy

Medial Aspect of foot

- proximal to navicular

- part of T posterior tendon

Usually will fuse with navicular (50%)

Issues

1.  Probably not a cause of flat foot

- excising accessory navicular / rerouting / reattaching tibialis posterior

- will not help pes planus

2.  Pain

- may fracture

Definition

Repeated dislocation of patella with minimal trauma

- 15-20% of paediatric acute patella dislocations

- more common girls 

- often bilateral

Dislocation occurs unexpectedly when quadriceps contracted with knee in flexion 

Direction

Anatomy

Unusual anatomic convergence of ilium, pubis and ischium

- covered entirely by hyaline cartilage

- except at acetabular fossa, which is the site of attachment of the ligamentum teres

- deepened by peripheral fibrocartilage labrum

2 column theory (Letournel and Judet)

Anterior Column 

- superior pubic ramus

- anterior acetabular wall, anterior dome

Anatomy

Pelvis is a true ring

- any anterior fracture must have a posterior injury as well

- integrity of the posterior sacroiliac complex is key

Bony Anatomy

2 innominate bones + sacrum

Symphysis pubis < 5mm

SI joint 2-4 mm

Anatomy

Size

2 x as strong as ACL

About the same length as ACL 38 mm

Cross sectional area 150% of ACL

13 mm diameter (thicker) 

2 Bundles

1.  Anterolateral

- most important

- double the size of the posteromedial

- tight in flexion

- try to reconstruct this bundle

Function

LHB primary function is humeral head depressor

Also accelerate / decelerate arm in overhead sports

Problems

Biceps problems usually occur with other pathology 

- rotator cuff / instability

3 main problems

1.  Degeneration

Epidemiology

Second most common  hindfoot after calcaneal fractures

Aetiology

Aviators Astragalus

Fall from height

- hyper-dorsiflexion injury

- neck of talus strikes the anterior tibia

Anatomy

More than half surface covered by articular cartilage

- medial articular wall straight

- lateral articular wall curves posteriorly