Exam techniques vary based on specific tendinopathy
Lateral epicondylitis
Medial epicondylitis
Patellar<unk> 
De Quervain tenosynovitis
Rotator cuff<unk> 
Bicipital tendinopathy
Popliteus tendinopathy
Iliotibial band syndrome
Medial tibial stress syndrome ("shin splints")
Consider labs if concern for infection:
CBC
CRP/ESR
CBC
CRP/ESR
Ultrasound
May aid the diagnosis
Findings include tendon disruption, increased blood flow, hypoechoic areas, or tendon thickening
X-Ray
Consider if concern for fracture, foreign body, or avulsion injury
MRI
Not frequently used in ED; may be used by specialist or in outpatient setting
May aid the diagnosis
Findings include tendon disruption, increased blood flow, hypoechoic areas, or tendon thickening
Consider if concern for fracture, foreign body, or avulsion injury
Not frequently used in ED; may be used by specialist or in outpatient setting
Tendonitis
Muscle contusion
Osteomyelitis
Ligamentous Injury
Dactylitis
Nerve compression
Knee fractures
Tumor