The purpose of this study is to see whether power Doppler sonography (PDS) can be used to diagnose synovitis in patients with inherited bleeding disorders.

Aim #1 - To determine if PDS can be used to diagnose synovial hypertrophy and inflammation in joint disease associated with inherited bleeding disorders. MRI will be used as a reference standard.

Aim #2 - To determine if PDS can be used to assess therapeutic response to treatment.

Aim #3 - To determine if PDS can be used as a screening tool for diagnosing early synovitis.

Inclusion Criteria:

• Diagnosis of inherited bleeding disorder

For Aim 1:

• Age of at least 6 years
• History of at least 4 bleeds in the same joint in the preceding 6 months
• Joint swelling, synovitis or deformity

For Aim 2:

• Meet inclusion criteria for Aim 1 and will be having a synovectomy

For Aim 3:

• Age of at least 1 year
• Have had at least 2 joint bleeds

Exclusion Criteria:

• Not meeting inclusion criteria