II. Precautions
- Hip XRay may miss non-displaced Femoral Fractures
- Consider MRI or CT for negative XRay with higher index of suspicion
- Parker (1992) Arch Emerg Med 9(1): 23-7 [PubMed]
- Hakkarinen (2012) J Emerg Med 43(20: 303-7 +PMID:22459594 [PubMed]
III. Imaging: Views
- Standard Views
- Anteroposterior Pelvis XRay (AP Pelvis XRay)
- Cross-Table Lateral Hip XRay
-
Hip Avascular Necrosis
- Frog-leg Xray
-
Hip Stress Fracture
- Maximal internal rotation hip
IV. Evaluation: Findings
-
Pelvic Fracture
- XRay identifies 90% of bony pelvic injuries
- Evaluate "rings and lines"
- Three pelvic rings
- Lines (iliopectineal line, ilioischial line, Shenton line, arcuate line)
- Anterior and posterior wall
- Acetabulum roof
- Extra views (largely replaced by pelvic CT)
- Inlet View, Outlet View and Judet View may identify subtle Fractures
-
Hip Stress Fracture
- Trace medial and lateral cortical margins of the femoral neck
- Follow S-shaped curve (where femoral head meets the femoral neck)
- Observe for sharp angle along the S-curve suggestive of Stress Fracture
- Trace medial (compressive) and lateral (tensile) trabecular lines through femoral shaft and into femoral head
- Observe closely for subtle disruptions in trabecular lines suggestive of Stress Fracture
- Trace medial and lateral cortical margins of the femoral neck
-
Hip Osteoarthritis
- Osteophytes (at acetabulum or femoral head)
- Subchondral cysts
- Bony sclerosis
-
Hip Avascular Necrosis
- Crescent sign (inconsistently seen on Xray)
- Femoral head flattening of the superior aspect
- Subchondral Fracture parallel to articular surface
- Crescent sign (inconsistently seen on Xray)
- Other findings
- Hip lesions (e.g. tumors)
V. References
- Shahideh (2013) Crit Dec Emerg Med 27(9):10-18