Direct versus indirect posterior malleolar fixation in the treatment of trimalleolar ankle fractures: Is there a difference in outcomes? 

SLR - June 2023 - Emily Lobos 

Title: Direct versus indirect posterior malleolar fixation in the treatment of trimalleolar ankle fractures: Is there a difference in outcomes? 

Reference: Sadd B, Rampertaap Y, Menken L, Whitlock K, Crook B, Baker R, Keller D, Liporace F, Gage M, Yoon R. Direct versus indirect posterior malleolar fixation in the treatment of trimalleolar ankle fractures: Is there a difference in outcomes? OTA International: The Open Access Journal of Orthopaedic Trauma. December 2022;5(4):e219 

Scientific Literature Review 

Level of Evidence: III 

Reviewed by: Emily Lobos 

Residency Program: West Penn Hospital, Allegheny Health Network, Pittsburgh, PA 

Podiatric Relevance: An ongoing debate surrounding ankle fracture management is the efficacy of direct fixation of a posterior malleolar fracture versus an indirect stabilization of this fragment via syndesmotic fixation. This article compares these two approaches in terms of the patients’ total pain and total function. Furthermore, the authors analyze some factors that affect both total pain and total function in their entire population of trimalleolar fractures giving a greater understanding of ankle fracture patient trends. 

Methods: This was a retrospective cohort study with 117 trimalleolar ankle fracture patients with at least one year of follow-up, 40 of which had direct fixation of the posterior malleolus and 77 with indirect fixation of the posterior malleolus through syndesmotic stabilization. The primary outcome of interest was short-term patient reported PROMIS scores for total pain (TP) and total function (TF). Secondary outcomes were finding factors that increased or decreased pain and function in the overall trimalleolar ankle fracture population. Variables collected included, but were not limited to, age, BMI, sex, complications, tobacco use, tourniquet time, if the fracture was open, and if an external fixator was used. 

Results: There was no significant difference found between the direct fixation (D) and indirect fixation (I) groups in terms of TP (D = 47.9 ± 8.0, I = 48.7 ± 9.8; p = 0.65) and TF (D = 47.0 ± 12.6, I = 44.5 ± 10.6; p = 0.19). On univariate analysis of the overall variables affecting TP, increased TP was seen in thosewith higher BMI, open fracture, tobacco use and higher tourniquet times. On univariate analysis of the overall variables affecting TF, decreased scores were seen in those of an older age, a higher BMI, Diabetes Mellitus and higher tourniquet times. In those who underwent external fixation prior to final internal fixation, incresaed TF scorews were noted. 

Conclusions: This study concluded there is no significant difference in the PROMIS scores of TP and TF for direct fixation versus indirect fixation of the posterior malleolar component of trimalleolar ankle fractures. It is important to note that the outcomes studied are short term and the study had limited power regarding the PROMIS score comparison. The secondary outcomes of the qualitative variables that significantly affected TP and TF are helpful to keep in mind while educating patients on what to expect after an injury and subsequent surgery as well as how to medicate patients for expected post-operative pain.