- See:
Classification and Column Theory
- Discussion:
- anterior column extends from symphysis pubis & obturator foramen thru acetabulum toASIS and up through the iliac crest;
- anterior column is less frequently fractured than
posterior column due to the frequency of posteriorly directed forces;
- frxs of the anterior column may comprimise any portion of the column;
- fracture line may extends from the middle of the pubic ramus to any point above the anterior segment of the iliac crest;
- most commonly, the anterior column fracture exits below the anterior inferior iliac spine;
- distal anterior column fractures:
- from exam of CT scan, look for frxs of superior pubic ramus which may enter inferior portion of acetabulum, violating joint;
- frx of anterior column frequently occur in middle or articular segment;
- in this region bone is relatively thin and overlies the joint;
- there is often comminution into quadrilateral plate surface;
- area is less accessible becuase of overlying iliopsoas muscle & obturator internus muscle;
- associated injuries:
anterior hip dislocation;
- Radiographs:
-
Internal (Obturator) Oblique View:
- visualizes iliopubic / iliopectineal line of pelvis & posterior acetabular rim;
- disruption of the iliopectineal line indicates anterior column frx;
- technique:
- patient is supine w/ involved side of pelvis rotated anteriorly 45 deg;
- central beam directed vertically toward the affected hip;
- Indications for Operative and Non Operative Treatment:
- CT scan can give an indication of the amount of involvement of the wt bearing dome;
- in the study by Vrahas et al 1999, a cadaveric biomechanical study was performed to determine the relative stability of anterior column,
posterior column, and transverse fractures;
- they noted that anterior column fractures with an anterior roof-arc angle (obturator oblique radiograph) of 25 degrees or less were unstable and required ORIF;
- fractures which fall outside of this zone can potentially be treated non operatively;
- ref: The Effects of Simulated Transverse, Anterior Column, and Posterior Column Fractures of the Acetabulum on the Stability of the Hip Joint.
MS Vrahas MD et al.
JBJS Vol 81-A. July 1999.
- Non Operative Treatment:
- fractures must fall outside of the danger zone (roof-arc angle on obturator oblique radiograph of 25 degrees) and hip reduction must be congruent;
- in some cases, traction is necessary to maintain the reduction;
- if once the patient is mobilized, new radiographs can be taken to ensure that the frx postion has not shifted;
- Surgical Treatment:
- frx of anterior column are exposed using
ilioinguinal approach w/ supine positioning;
- initial fixation of anterior column may require interfragmentary screws
& plates to stabilize frx of
iliac wing, depending on frx type;
- during reduction, reestablishment of pelvic brim allows reconstruction of entire anterior column (realize that the iliac
fossa is more concave than is often appreciated);
- initial reduction reduction may be obtained w/ lateral traction applied by a half pin inserted in the femoral neck;
- early application of precurved plates simplifies the reduction;
- plate is slide underneath musculature of
iliopsoas and femoral vessels;
- plate attached to body of pubis w/ a screw & then plate is rotated along superior
pubic ramus until it sits congruently on iliopectineal line and pelvic brim;
- plate extends posteriorly along pelvic brim from posterior part of iliac fossa and
anteriorly to the pubic symphysis;
- screw purchase is best obtained far medially on superior pubic ramus and posteriorly, in iliac wing;
- because frx of ischiopubic ramus are difficult to reach & do not appear to significantly influence end results,
no attempt is made to stabilize this component of the fracture;
- Case Example:
25 year old male involved in MVA, sustaining an iliac wing fracture and a low transverse acetabular frx;
- Danger Zone: (from Benedetti et. al. 1996)
- diagram shows danger zone at 1, 2, and 3 cm above the inferior acetabulum rim;
- in general the danger zone extends about 2.5 cm medially from the acetabular rim;
- Screw Placement into the Anterior Column:
- applicable for
T-type frx,
transverse frx, and
both column frx;
-
1 cm above the inferior edge of the acetabulum:
- at 0.5 mm lateral to the pelvic brim, screw are inserted at 25 deg of medial angulation (screw length 20 mm);
- at 1.0 cm lateral to the pelvic brim, screw are inserted at 35 deg of medial angulation (screw length 20-25 mm);
- at 1.5 cm lateral to the pelvic brim, screw are inserted at 45 deg of medial angulation (screw length 25 mm);
-
2 cm above the inferior edge of the acetabulum:
- at 0.5 mm lateral to the pelvic brim, screw are inserted at 30 deg of medial angulation (screw length 20 mm);
- at 1.0 cm lateral to the pelvic brim, screw are inserted at 40 deg of medial angulation (screw length 20-25 mm);
- at 1.5 cm lateral to the pelvic brim, screw are inserted at 50 deg of medial angulation (screw length 25 mm);
-
3 cm above the inferior edge of the acetabulum (level of ASIS):
- at 0.5 mm lateral to the pelvic brim, screw are inserted at 20 deg of medial angulation (screw length of 45 mm);
- at 1.0 cm lateral to the pelvic brim, screw are inserted at 30 deg of medial angulation (screw length of 45-50 mm);
- at 1.5 cm lateral to the pelvic brim, screw are inserted at 40 deg of medial angulation (screw length of 50 mm);
- Percutaneous Screw Placement:
Anterior column fractures of the acetabulum.
Anatomic Considerations of Plate Screw Fixation of the Anterior Column of the Acetabulum;
J.A. Benedetti, N.A. Ebraheim, R. Xu, and R.A. Yeasting.
J. Orthop Trauma, Vol 10. No. 4. 1996.
Acetabular fracture fixation via a modified Stoppa limited intrapelvic approach. Description of operative technique and preliminary treatment results.
Technical Tricks. Percutaneous Fixation of the Columns of the Acetabulum. A New Technique.
AJ Starr et al.
J. of Orthopaedic Trauma. Vol 12. No 1. p 51-58.
- PreOp Planning: 
