Abstract
Introduction: The possibility of occult hip fracture in older patients after a fall is a common problem. The value of various clinical signs to determine which patients require further investigation has not been reported.
Methodology: MRI register was hand searched to identify all patients who had MRI scan between July 2000–June 2006 for suspected occult hip fracture. 64 patients were identified. 33 patients had occult proximal femoral fractures. 27 patients had no fracture.
Results: More patients with fracture were living in their own home (20/26), were independent for daily living (20/26) and were not independently mobile(19/26) compared to patients without a fracture (14/22, 11/22 and 6/22 respectively). 7 patients with fracture and 2 patients without fracture were able to weight bear. 13 patients with fracture and 10 patients without fracture had unrestricted straight leg raise ability. 7 patients with fracture and 16 patients without fracture had no pain on axial loading. The value of individual tests was evaluated using Fisher exact and chi square analysis; with Bonferroni correction for multiple comparisons (10 tests) p< 0.005 was deemed significant. Pain on axial loading of the limb and pre-fracture patient mobility were both associated with the presence of a fracture (p< 0.005).
Discussion: These data indicate that although patients who were independently mobile before the fall and who do not have pain on axial compression of the limb are less likely to have a fracture, these signs alone or in combination will not exclude a fracture. Other widely used signs (eg ability to straight leg raise) appear of little predictive value. On the basis of our data, we believe it is essential to have a policy of MRI scanning of patients with severe hip pain but normal x rays after a fall as it does not seem possible to clinically exclude a fracture.
Correspondence should be addressed to Mr John Hodgkinson, BHS, c/o BOA, The Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.
