Intra-articular fragments

Intra-articular fracture fragments  are a form of intra-articular bodies that result from traumatic injuries as fractures or dislocations.

Clinical presentation

Symptoms are variable and also depend on the underlying cause and extent of the injury, but usual complaints are pain, limited motion clicking, locking, snapping, swelling.

Pathology

Intra-articular fracture fragments consist of bone, cartilage and bone or pure cartilage again depending on the extent and aetiology of the injury.  

If intra-articular chondral or osteochondral fragments are not identified and removed, they can progress to early osteoarthritis ¹.

Aetiology

Typical aetiologies of intra-articular fracture fragments: 

• articular fractures especially if multifragmentary or even comminuted
• dislocations and fracture-dislocations
• osteochondral fractures
• chondral fractures

Radiographic Features

Plain radiograph and CT

Osseous fragments are usually  radiodense with sharp edges located within the joint space and easily detected on CT, but under many occasions difficult to detect on plain radiography ^1,2. Computed tomography scans should therefore always performed before and after surgery in case of fracture-dislocations ^1,2 or complex and/or comminuted articular fractures.

Pure chondral fragments are not easily detectable neither on plain radiograph nor on conventional CT.

MRI

Osseous or osteochondral fragments  show thin sclerotic edges and may have parts of trabecular bone. Pure chondral fragments are of intermediate signal intensity in T1 and PD and are hypointense in T2 and PDFS. They are best detected on normal not fat-saturated proton density or T2-weighted images due to the improved contrast versus synovial fluid ³.

Treatment and prognosis

Intra-articular fracture fragments are usually treated operatively or athroscopically ^{1,2 4-7} and need to be removed or adapted if they are suitable for rescue and technical fixation ^4,7. Otherwise they cause chondral damage and perhaps even more chondral or osteochondral fragments and early osteoarthritis ².

See also

• intra-articular loose bodies
• articular fractures
• osteochondral fractures
• chondral fractures