Prospective assessment of key factors influencing treatment strategy and outcome of fragility fractures of the pelvis (FFP)
Authors: Rommens Pol Maria , Hopf Johannes Christoph , Arand Charlotte , Handrich Kristin , Boudissa Mehdi , Wagner Daniel 
Published: February 2022

Abstract
Background
Fragility fractures of the pelvis (FFP) are a clinical entity with an increasing significance in clinical practice. Little is known about the conditions, which influence decision making and outcome.

Setting
Level I trauma center.

Material and methods
Prospective assessment of selected parameters of patients, who were admitted with a FFP in a 2-year period. Fractures were classified in accordance with the Rommens and Hofmann classification. Living environment, level of autonomy (independent walking), type of treatment (conservative versus operative), type of surgical technique, European Quality of Life-5 Dimensions-5 Levels (EQ-5D-5L), Short Form-8 Physical Component Score (SF-8 PCS) and Short Form-8 Mental Component Score (SF-8 MCS), Barthel Index, Parker Mobility Score (PMS) and Numeric Rating Scale (NRS) were collected at primary presentation (t1), at discharge (t2) and after 3 (t3) and 12 months (t4). Length of hospital stay, in-hospital complications, surgery-related complications, new osteoporotic fractures and mortality rate within the first year were also registered. The key factors influencing the choice of therapy and outcome were looked for.

Results
110 patients, 99 women (90%) and 11 men (10%), were included in the study. Their mean age was 79.2 years (SD 10 years). Fourteen patients had FFP type I (12.7%), 59 FFP type II (53.6%), 11 FFP type III (10%) and 26 FFP type IV fractures (23.6%). All patients with FFP type I were treated conservatively. 48 patients with FFP types II-IV were treated conservatively and 48 operatively. Patients, who got a conservative outpatient treatment first and were hospitalized later, had higher FFP fracture types at admission. Operatively treated patients were hospitalized at a median of 33.5 days after the beginning of complaints, whereas the median day of admission of the conservative group was the day of trauma (p < 0.001). The operatively treated patients were hospitalized in a worse clinical condition (SF-8 PCS, EQ-5D-5L, autonomy). Length of stay (LoS) of operatively treated patients was significantly longer than of conservatively treated (p < 0.001). There was a tendency to more in-hospital complications in the operative group (p = 0.059). The rate of surgery-related complications (8.3%) was low with only one revision needed. Selected outcome parameters improved during the observation period nearly reaching the level before FFP after 1 year. SF-8 PCS, Barthel index and rate of patients living home were higher in the operative group at t4. The improvement of autonomy (independent walking) between t1 and t4 was significant in the operated group (p = 0.04) but not in the conservative group (p = 0.96). One-year mortality rate was 11.7% with no difference between the fracture types. One-year mortality rate of conservatively treated patients with FFP type II-IV was 13.5% versus 6.9% in the operative group (p = 0.38).

Conclusion
Conservative treatment is appropriate in patients with FFP type I as well as in patients with FFP type II, provided that the last ones are hospitalized immediately after the traumatic event. Surgical treatment is recommended in patients with higher fracture types, with delayed presentation or after unsuccessful conservative treatment. In the conservative and operative group, all selected parameters considerably improved between t1 and t4 with a steeper increase in the operative group. The rate of postoperative complications is low. The 1-year mortality rate is the lowest in the operative group. Surgical stabilization of FFP is safe and reliable provided it is performed with care and in the appropriate target group.