2025/03/18 | People | Biomechanics

PhD Defense: Christina Wapp Develops Fragility Hip Risk Calculator

On March 18, 2025, Christina Wapp successfully defended her PhD thesis titled: “The Development of a Personalised Fragility Hip Risk Calculator.” In this work, Christina presents a novel hip fracture risk calculator based on a mechanic stochastic framework. By combining an existing model used to describe the occurrence of a fall with a stochastic distribution, she could identify the fall events resulting in a fracture and calculate the fracture risk.

(©Christina Wapp)

Her main findings showed that the calculator models the underlying process of hip fractures by combining the stochastic aspects of a fall with the mechanistic elements of an impact on the hip. Christina’s model reflects key observations from empirical data – such as the influence of the rate of falling, the femoral bone strength and the soft tissues covering the hip on the fracture risk – and is therefore capable of capturing the intrinsic aspects that affect the risk of fragility hip fractures.

Congratulations to Dr. Christina Wapp on this incredible achievement in developing analytical tools for clinical use!

Publications:

Wapp, Christina; Gugler, Yvan; Cameron, Paula Margaret Noonan; Dudle, Alice; Frauchiger, Daniela Angelika; Papageorgiou, Maria; Biver, Emmanuel; Ferrari, Serge; Lippuner, Kurt; Zysset, Philippe (n.d.). A novel fragility hip fracture risk calculator based on a mechanic and stochastic modelling approach (Manuscript in preparation).

Cameron, Paula Margaret Noonan; Dudle, Alice; Gugler, Yvan; Wapp, Christina; Frauchiger, Daniela Angelika ; Ith, Michael; Egli, Rainer Josef; Heverhagen, Johannes; Scheffler, Matthias; Hars, Mélany; Papageorgiou, Maria; Biver, Emmanuel; Ferrari, Serge; Lippuner, Kurt; Zysset Philippe (n.d.). Clinical measurements of trochanteric soft tissue thickness and stiffness in the AFFIRM-CT cohort (Manuscript in preparation).

Dudle, Alice; Ith, Michael; Egli, Rainer Josef; Hevergagen, Johannes; Gugler, Yvan; Wapp, Christina; Frauchiger, Daniela Angelika; Lippuner, Kurt; Jackowski, Christian; Zysset, Philippe (2024). Asynchronous calibration of a CT scanner for bone mineral density estimation: sources of error and correction. JBMR Plus 8(9). Oxford University Press (United Kingdom) 10.1093/jbmrpl/ziae096

Wapp, Christina; Mittaz Hager, Anne-Gabrielle; Rikkonen, Toni; Hilfiker, Roger; Biver, Emmanuel; Ferrari, Serge; Kröger, Heikki; Zwahlen, Marcel; Zysset, Philippe (2024). Validation of a fall rate prediction model for community-dwelling older adults: a combined analysis of three cohorts with 1850 participants. BMC Geriatrics 24(1), p. 287. BioMed Central 10.1186/s12877-024-04811-x

Wapp, Christina; Biver, Emmanuel; Ferrari, Serge; Zysset, Philippe; Zwahlen, Marcel. (2023). Development of a personalized fall rate prediction model in community-dwelling older adults: a negative binominal regression modelling approach. BMC Geriatrics 23(1) p. 200. BioMed Central 10.1186/s12877-023-03922-1

Wapp, Christina; Mittaz Hager, Anne-Gabrielle.; Hilfiker, Roger; Zysset, Philippe (2022/2023). History of falls and fear of falling are predictive of future falls: Outcome of a fall rate model applied to the Swiss CHEF Trial cohort. Frontiers in Aging 3, p. 1056779. Frontiers Media S.A. 10.3389/fragi.2022.1056779. Erratum in: Frontiers in Aging 4, p. 1235431. Frontiers Media S.A. 10.3389/fragi.2023.1235431