Circumstances of occupational same-level falls and risk of hip fracture in women over 45 years of age who fell at work

Objectives: This case control study examined the association between circumstances of falls and the risk of hip fracture in women over 45 years of age who suffered a same-level fall at work.

Method: 373 cases of hip fracture and 1360 matched controls who suffered injuries other than fracture from same-level falls were selected from a large workers compensation database using ICD-9 codes. Cases and controls were matched on age (+/- 3 years), season, industry and state with the goal to achieve 1:4 case control ratio. Injury event narratives were coded by two trained investigators blinded to injury outcome. Information was obtained about manual material handling at the time of fall, falling on ice, initiating event, and whether the fall occurred outdoors. To control for information bias, length of the injury event narrative was included in the multivariable model.

Result: The mean age of hip fracture for cases and controls was 63.2 (9.59) and 61.7 (8.74) years respectively. 35.7% of cases were from the service industry, 30.0% from retail trade and 13.4% from manufacturing. Falling outdoors was associated with 37% reduced risk of hip fracture (OR 0.63, 95% CI 0.42-0.93). Falling on ice was marginally associated with increased risk of hip fracture (OR 1.59, 95% CI 0.85-2.98.). Slipping, as opposed to tripping, manual material handling, and length of injury event narrative were not significantly associated with risk of hip fracture.

Conclusion: Circumstances of falls could significantly affect the risk of hip fracture in working women over 45 years of age.