Abstract
Purpose of the study: To determine usefulness of skyline x-ray in diagnosis of patellofemoral osteoarthritis.
Materials and Methods: 50 patients scheduled to undergo knee surgery, had standard antero-posterior, lateral and skyline x-rays of their affected knee. At operation, their patellofemoral joints were graded into two groups according to presence or absence of osteoarthritis. Their lateral and skyline x-rays were also graded into the same two groups, according to presence or absence of patellofemoral osteoarthritis. The two x-ray views were then compared individually against operative findings.
Results: The skyline view had sensitivity of 79% (95% confidence intervals (C.I.) 66% to 93%) and specificity of 80% (95% C.I. 62% to 98%). The lateral view had sensitivity of 82% (95% C.I. 69% to 95%) and specificity of 65% (95% C.I. 44% to 86%).
Conclusion: There was no statistically significant difference between the two x-ray views in terms of sensitivity and specificity in the diagnosis of patellofemoral osteoarthritis of the knee joint. Hence, we cannot recommend the skyline view as a routine radiological investigation in all cases of suspected patellofemoral osteoarthritis.
Honorary Secretary – Mr Roger Smith. Correspondence should be addressed to BASK at the Royal College of Surgeons, 35 - 43 Lincoln’s Inn Fields, London WC2A 3PN
