Wiberg's 1953 paper formalizes the CE (center-edge) angle as the radiographic tool for quantifying acetabular coverage in adults and children. It then reports outcomes of the shelf acetabuloplasty in 85 hips with dysplasia, subluxation, and dislocation. The paper answers two questions: how do we measure the problem, and when should we operate?
Roughly one in four hips that develops osteoarthritis does so because of dysplasia or subluxation — a natural history finding from this paper that justifies treating radiographic undercoverage before patients become symptomatic.
The CE angle is the tool Wiberg gave us to act on that rationale. When you see a CE angle below 20° on a pelvis film in an adult, that is a dysplastic hip. In a child aged 3–17, the threshold drops to below 15°. These numbers belong on a flashcard.
For subluxation, operate early: results are 85% excellent/good before age 11, versus 71% overall. Every year of delay narrows the remodeling window and moves the patient closer to irreversible cartilage damage.
For unreduced dislocations presenting after age 7–8, do not attempt reduction. The risk of femoral head necrosis is prohibitive. A high shelf without repositioning the head is the appropriate salvage.
This paper is the conceptual ancestor of every modern periacetabular osteotomy indication: the CE angle it defined is still the primary radiographic criterion used today to decide when acetabular coverage is inadequate enough to warrant surgery.
Wiberg's 1953 paper formalizes the CE (center-edge) angle as the radiographic tool for quantifying acetabular coverage in adults and children. It then reports outcomes of the shelf acetabuloplasty in 85 hips with dysplasia, subluxation, and dislocation. The paper answers two questions: how do we measure the problem, and when should we operate?
Roughly one in four hips that develops osteoarthritis does so because of dysplasia or subluxation — a natural history finding from this paper that justifies treating radiographic undercoverage before patients become symptomatic.
The CE angle is the tool Wiberg gave us to act on that rationale. When you see a CE angle below 20° on a pelvis film in an adult, that is a dysplastic hip. In a child aged 3–17, the threshold drops to below 15°. These numbers belong on a flashcard.
For subluxation, operate early: results are 85% excellent/good before age 11, versus 71% overall. Every year of delay narrows the remodeling window and moves the patient closer to irreversible cartilage damage.
For unreduced dislocations presenting after age 7–8, do not attempt reduction. The risk of femoral head necrosis is prohibitive. A high shelf without repositioning the head is the appropriate salvage.
This paper is the conceptual ancestor of every modern periacetabular osteotomy indication: the CE angle it defined is still the primary radiographic criterion used today to decide when acetabular coverage is inadequate enough to warrant surgery.