This exercise sheet provides a systematic framework for analysing an AP pelvis radiograph. Work through each section in order — pelvic orientation must be confirmed first, as rotation and tilt affect all subsequent measurements.
1. Pelvic Orientation
Confirm adequate positioning before measuring anything else.
- Rotation — neutral / left / right
- Tilt — sacrococcygeal joint to pubic symphysis: ___ cm
- Obliquity — neutral / right high / left high
2. Acetabular Version
- Cross-over sign — Right: positive / negative Left: positive / negative
Present = acetabular retroversion (anterior wall crosses posterior wall line) - Ischial spine sign — Right: positive / negative Left: positive / negative
Ischial spine projects medially into the pelvis = retroversion
3. Tear Drop
- Shape — normal / thin / reversed / wide
Thin or absent tear drop suggests medial wall deficiency; wide suggests protrusio
4. Degenerative Changes
- Osteophytes — location / severity: ___
- Cysts — location / size: ___
- Joint space — ___ mm (normal ≥ 3–4 mm)
5. Subluxation
- Medial widening — present / absent
- Shenton's line break — present / absent
- Rim fracture — present / absent
6. Sourcil (Acetabular Roof)
The sourcil is the sclerotic weight-bearing dome of the acetabulum. Assess shape, coverage, and inclination.
- Lateral coverage (LCE angle) — ___° (normal ≥ 25°; approximately 80% femoral head coverage)
- Medial coverage (MCE angle) — ___° (normal ≥ 25°)
- Shape — concave / flat / convex (normal = concave)
- Tönnis angle (sourcil inclination) — ___° (normal 0–10°; >10° suggests instability)
- Labral ossification — present / absent
7. Wall Coverage
- Anterior wall — coverage ___% (normal ~20%)
- Posterior wall — coverage ___% (normal ~50%)
- Posterior wall LCE — ___° (normal 25–35°)
8. Femoral Head
- Epiphyseal extension — normal / abnormal
- Subchondral fracture — present / absent
- Collapse — present / absent
9. Proximal Femur Geometry
- Alpha angle (AP view) — ___° (normal < 50°; >55° suggests cam impingement)
- Alpha angle (lateral view) — ___°
- Trochanteric height — normal / high / low
- Neck length — normal / short / long
- Fovea angle — ___°
10. Summary — Morphological Variations Affecting
- Cartilage space — ___
- Dysplastic features — ___
- Impingement risk factors — ___
- Abductor function — ___