Due to scapulothoracic articulation disorder
1. Neurological Origin
A. Spinal Accessory Nerve / Trapezius palsy
B. Long Thoracic Nerve / Serratus Anterior palsy
C. Dorsal Scapular Nerve / Rhomboids palsy (rare)
2. Osseous Origin
Instability in at least 2 planes
- postero-inferior
- antero-inferior
- antero-postero-inferior
Recognised as a common problem
- often misdiagnosed
Most patients athletic
Supracondylar fracture of humerus
Both bone forearm fractures
Parosteal OS
- bone is not continuous with cortex in MO
3% incidence in elbow joint trauma to some degree
Adolescents & young adults
Usually between 12 - 21 years
Throwing athletes / gymnasts
Little Leaguer's Elbow
- combination of capitellar OCD and MCL injury
- a repetitive throwing injury / seen in pitchers
1. Trauma & Overuse
Common throwing sports / gymnastics
10% of elbow tendonitis
Overuse injury
- poor swing in golf
- poor throwing technique
- overuse of topspin in tennis
- occupational (repetitive hammering / screwing)
Some patients also have lateral epicondylitis
Tenderness CFO
Stimulate pain
- flexion of WJ with fingers resisting
Lateral : Medial 9:1
4th & 5th decades
- M = F
- 75% dominant arm
50% of regular tennis players
- especially > 2 hrs / week
Insertion pathology / Enthesopathy
Over-extension of the elbow with supination / pronation
Lateral epicondyle
- anconeus from posterior face
- ECRB and EDC from anterior face (CEO)
Relatively rare
Average age 50
Men 4:1 Women
Usually dominant arm
Primary
- associated with strenuous manual labour
Secondary
- trauma
- OCD
- synovial chondromatosis
- valgus extension overload / MCL insufficiency
Occurs 10% of supracondylar humeral fractures
- varus malunion
Lateral condyle fracture
- AVN trochlea
Growth arrest of medial aspect physis
- rare
- post traumatic
A valgus knee has a tibiofemoral angle of > 10o
Inflammatory
- RA