PMC6854257_01
Preoperative radiographs and magnetic resonance images. (a-c) Preoperative standard radiographs of the patella. (d, e) Preoperative magnetic resonance images. The arrowheads indicate the neglected osteochondral fracture dislocation of the patella.
CRIOR2019-2904782.001.jpg
PMC6854257_01_CRIOR2019-2904782.001.jpg
fig1
Initial radiographs showed lateral subluxation of the right patella with one fragment in the knee joint (Figures 1(a)-1(c)). Magnetic resonance imaging (MRI) demonstrated an osteochondral defect over the central aspect of the patella with a large loose body (Figures 1(d) and 1(e)).
(a) Intraoperative view of osteochondral fracture dislocation of the patella. (b) The arrowhead indicates the fractured fragment. The fragment is perfectly reduced and fixed by two cannulated screws. The screw head is totally embedded.
CRIOR2019-2904782.002.jpg
PMC6854257_01_CRIOR2019-2904782.002.jpg
fig2
Finally, reduction was performed, and the fracture was fixed with two headless screws (Acutrak , Acumed, Beaverton, Oregon) (Figure 2(a)). Intraoperative findings revealed the osteochondral fragment (30 x 25 x 10 mm3) from the central aspect of the patella (Figure 2(b)), an intra-articular loose body, hemarthrosis, and rupture of the medial patellofemoral ligament, which caused lateral subluxation of the patella.
Postoperative status at 3 months. (a, b) The patient can do squats and sports activities as well as she could before the injury.
CRIOR2019-2904782.003.jpg
PMC6854257_01_CRIOR2019-2904782.003.jpg
fig3
She could do squats and sports activities as well as she could before the injury (Figures 3(a) and 3(b)).
(a) Postoperative standard radiographs at the 1-week follow-up. Note that the dislocation and articular surface are corrected. (b) Postoperative standard radiograph showing a healed fracture site and the implant in situ at 9 months.
CRIOR2019-2904782.004.jpg
PMC6854257_01_CRIOR2019-2904782.004.jpg
fig4
Follow-up radiographs also demonstrated healing of the osteochondral fracture (Figures 4(a) and 4(b)).
(a) Postoperative second-look arthroscopy at 1-year follow-up showing blurring of the cartilage and metallosis but no obvious degenerative changes in the cartilage. (b, c) Postoperative radiograph shows the healed fracture.
CRIOR2019-2904782.005.jpg
PMC6854257_01_CRIOR2019-2904782.005.jpg
fig5
There were no significant degenerative changes in the cartilage (Figures 5(a)-5(c)).