We aimed to investigate the clinical consequences of intraoperative acetabular fractures. Between 2003 and 2012, a total of 3391 cementless total hip arthroplasties (THA) were performed at the Dept. of Orthopaedics, Innsbruck Medical University. Of those, a total of 160 patients underwent a CT scan within 30 days postoperatively. The scans of 44 patients were not suitable for analyse due to thick scan layers. Of the remaining 116 patients, 76 had a fracture. Reasons for CT-scans were suspected bleeding, hip pain, abdominal symptoms, etc. The fractures included 59 isolated acetabular fractures, the rest of fractures was in the superior or inferior pubic ramus or the tuber ischiadicum. Four cases out of the 59 acetabular fractures underwent revision surgery due to periprosthetic joint infection after 0, 2, 10 and 23 months. Four patients underwent revision due to cup loosening after 13 and 14 days as well as after 16 and 24 months. Of those, three showed a central acetabular fracture with protrusion. In 33 of the remaining 51 patients, a minimum of 3 x-rays was available for migration analysis with EBRA. In 6 patients, the x-rays were not comparable to each other. The 27 remaining acetabular fractures were categorised according to AO classification in 62A1 (1; posterior wall), 62A2 (16; posterior column), 62A3 (6; anterior wall), and others (4). Four hips showed initial migration of more than 3 mm in the first 6 months. One had a central fracture, and was lost for follow-up after 8 months. Two had an anterior column fracture and showed no further migration after 6 months. One showed also a radiolucency of more than 2 mm in all 3 zones and was lost for follow-up. We conclude that intraoperative acetabular fractures occur more often than we expected. Fractures of the acetabular ring involving one column do not seem to compromise the long-term stability of the implant. Central fractures required revision or showed loosening proved by high cup migration.
Penetration of the dorsal screw when treating
distal radius fractures with volar locking plates is an avoidable complication
that causes lesions of the extensor tendon in between 2% and 6%
of patients. We examined axial fluoroscopic views of the distal
end of the radius to observe small amounts of dorsal screw penetration,
and determined the ideal angle of inclination of the x-ray beam
to the forearm when making this radiological view. Six volar locking plates were inserted at the wrists of cadavers.
The actual screw length was measured under direct vision through
a dorsal approach to the distal radius. Axial radiographs were performed
for different angles of inclination of the forearm at the elbow. Comparing axial radiological measurements and real screw length,
a statistically significant correlation could be demonstrated at
an angle of inclination between 5° and 20°. The ideal angle of inclination
required to minimise the risk of implanting over-long screws in
a dorsal horizon radiological view is 15°. Cite this article:
