Transient Synovitis

Definition

 

Transient synovitis of unknown aetiology with complete resolution

 

Epidemiology

 

Most common cause of hip pain

- 1 /1000

 

May occur in 3% of children with majority not seeking medical attention

 

Wide range of age

- from 9 / 12 to teenagers

- usually 3 - 8 years

- peak 6 years / same as Perthes

 

More common in

- boys 2:1

- caucasian

- never bilateral

 

Aetiology

 

1/3 viral 1/3 trauma 1/3 unknown

 

1. Infection

 

? Infectious condition

- supported by frequent association with current or antecedal illness

- viral or bacterial

- most commonly ENT

- no specific viral antibodies found

 

2. Trauma

 

May be contusion of hip

- history of trauma in 30%

 

3. Allergic hypersensitivity

 

May be hypersensitivity response

- 25% have atopia

- dramatic response to antihistamines & steroids

 

Pathology

 

Culture negative synovial effusion

 

Synovial hypertrophy 2° to non-pyogenic inflammatory reaction

 

NHx 

 

Limited duration of symptoms

- average 10 days

- may be 8 weeks

 

Recurrence uncommon < 10%

 

Associated with Perthes Disease in 1.5%

- probably not causative

 

Clinical

 

Acute onset of unilateral hip pain

- usually hip & groin

- may be thigh & knee

 

Findings

 

Limp

Inability to weight bear

Hip held in flexion & ER

Protective muscle spasm

Restricted ROM especially IR

May be low-grade fever < 38°

 

Blood Tests

 

May be mild elevation of 

- WCC

- ESR

- CRP

 

Xray

 

Usually normal

- exclude other conditions

 

May be mild changes in hip

- coxa magna / femoral neck widening

- ? 2° to hypervascularisation

- not symptomatic

 

US

 

May show effusion

 

Differential Dx

 

Septic Arthritis

- see Miscellaneous / Infection / Septic Arthritis

- Kocher criteria (WB / ESR / fever / WCC)

Osteomyelitis

 

Perthes / SUFE / JRA 

 

Management

 

Important to rule out other pathology

 

Symptomatic only

- rest in bed and analgesia until FROM shown to decrease recovery time & recurrence

- traction only for severe cases that fail to settle

- NSAID

- PWB on crutches until limp resolves