The diagnosis of osteochondral fractures and medial patellar retinaculum injuries that originate as a result of Traumatic Patellar Dislocation (TPD) appears to be crucial for establishing the treatment strategy. Those injuries may be efficiently recognized by means of ultrasonography (USG).
Material and methods: The analysis of the USG patterns in 22 knees after TPD in 21 patients treated between 2004 and 2007 was proceeded. In all children knee USG examination followed its clinical examination and X ray imaging. The standard USG knee assessment was supplemented by patellar articular cartilage assessment according to the author's technique and dynamic examination of the functional efficiency of the Medial Patello-Femoral Ligament (MPFL). 15 patients were treated surgically and 7 conservatively.
Results: The following USG patterns of TPD--concomitant injuries were observed: avulsion fracture of the patellar insertion of MPFL (16), injury of MPFL fibres (17), injury of MPFL femoral insertion (4), intramuscular hematoma of the quadriceps muscle (3), osteochondral fracture with presence of the intraarticular loose body and corresponding fracture-site leasion of the articular surface of the lateral femoral condyle or patella (12), and non-full thickness articular cartilage injury (8). The sonographic diagnoses were confirmed in 20 out of 22 knees (91%), including 13 out of 15 patients operated.
Conclusions: TPD may result in numerous injuries of the knee extensor apparatus and articular cartilage. The authors' experiences displayed usefulness of the USG in diagnosis of these damages. Using dynamic assessment the patellar articular cartilage as well as a function of the MPFL can be examined.