probability – the briefest possible review.

P(event A) = relative frequency of Event A / large number of events (where A is possible)
Conditional Probability = p(a) given that b has already happened.  P(a|b)
independent events: event b has absolutely no effect on P(a).  P(a)= (a|b)

if a and b are independent, P(A & B) = P(B)P(A)

dependent events : P(a) is not the same [...]

Biostatistics and Epidemiological Methods

Relative Risk = ratio of rate of disease in those exposed to that rate among those not exposed.

 e.g. RR(lung CA) = rate of lung CA in smokers / rate of lung CA in nonsmokers

Attributable Risk = rate of disease in exposed – rate of disease in non-exposed
Controlled Clinical Trial

 prospective study
split participants into 2 groups (usually [...]

In case of no pulse…

Here’s the ACLS Algorithm (2005)

Rheumatoid Forefoot

Deformity 

 Hallux valgus
 Lesser toe MTP extension and IP flexion
 Distal migration of plantar fat pad

When confronted with a hallux valgus deformity, look and ask about RA
 
Non-operative Rx

 Deep shoe with metatarsal bar and cut outs for prominences

Operative Rx

 Dwyer procedure

1st MTP fusion
 2-5 MT head excision with interposition of divided extensor tendon
2-5 PIP fusion

Hoffman

Same, without the 1st MTP fusion

Elbow Arthroplasty

Constrained – used only in cases of severe bone loss due to high loosening rate
Semi-constrained – eg. Coonrad-Morrey – most commonly used, sloppy hinge providing some varus & valgus motion
Unconstrained – eg. Capitellocondylar – unlinked metal on poly articulation, require normal ligaments
Fascial – coverage of articulation with fascia lata autograft
Complications – in implant arthroplasty, humeral [...]

Congenital Clubfoot overview

Trend toward nonoperative management.

Ponseti

Kite-Lovell

Need well organized approach to surgical Rx of residual deformity

forefoot adductus

cavus

heel valgus or varus

dorsal bunion

dynamic forefoot supination

N.B. different clinical presentations
Specific Rx recommendations for kids at different ages – in evolution

? accepted age for Tib. ant transfer

conventional wisdom  =2.5 years

? 6-12 months

? use of Ponseti method for neglected cases in which children presents at [...]

Patella Fractures / Patellar Tendon Injuries

Q1: draw tension band and describe mechanism by which it works.  (will look for a picture to demonstrate this – if you have one, please email it to me) 
Effect of Total Patellectomy?  20-30% decrease in strength of extensor mechanism.

d/t decrease in moment arm by ~1/3

Patellar tendon avulsion

Repair with Krackow stitch.

Through drill holes in patella (tie over bony bridge)

Protect with [...]

MRI – a quick review

T1

define anatomy (best signal-to-noise ratio)

fat is bright

look at vascularity on fat-suppressed T1 images

T2

used to look for reactive edema

water is bright

variants include spin-echo, fast-spin echo, short tau inversion recovery

fat-suppression allow better discrimination of edema from fat and soft tissue

Kienbock’s Disease

 Kienbock’s is the eponym for AVN of the lunate.
Etiology is not known but thought to be related to ulnar negative variance.
There is often a history of trauma
Men are more commonly affected than women
Age is usually 20-40
Clinical Presentation 
Early: dorsal wrist pain, perhaps limited ROM
Later: Synovitis, worse ROM, grip weakness
Later Still: pain at rest.
 
Management is based on [...]

Lateral approach to the Knee

Position

supine
sandbag under buttock
tourniquet

Landmarks

Lateral border of patella
lateral joint line
Gerdy’s tubercle

Incision

 long hockey stick (err posterior to IT band)

Internervous plane

 Iliotibial band (superior gluteal n. – G.max & TFL) / Biceps Femoris (sciatic)
consider identifying and protecting sciatic nerve (behind biceps femoris) and exposing through more posterior interval if goal is PLC reconstruction.
can also use Vastus Lateralis (femoral n.) / [...]