• Deltoid ligament (DL) injuries are common in ankle trauma, yet their optimal management remains debated.

• Most trauma literature considers DL injury as an isolated ankle problem, whereas foot-and-ankle specialists view the
ankle and the foot as a complex. This disconnect leaves a critical knowledge gap that our work aims to address.

• As we know, every post-traumatic collapsing foot deformity involves a DL injury, but not every DL necessarily
progresses to such a deformity.

• We introduce the concept of the DL as a tri-articular stabilizer within the medial ankle ligament complex, contributing to
the stability of the tibio-talar, subtalar (ST), and talo-navicular (TN) joints.

• Neglecting this broader stabilizing role may lead to irreversible foot sequelae, such as post-traumatic plano-valgus or
plano-abductus deformities. Therefore, DL injuries should be systematically recognized in both acute and chronic
settings, whether treated conservatively or surgically.

• In this expert opinion, we synthesize current anatomical, biomechanical, and clinical evidence together with our
experience to outline key diagnostic principles and therapeutic considerations for the management of DL injuries.

Abstract

Background: Middle facet subluxation (MFS) of the subtalar joint is a key indicator of peritalar subluxation in progressive
collapsing foot deformity (PCFD). Although its assessment relies on weightbearing computed tomography (WBCT),
it remains unclear which weightbearing radiographic (WBR) measurements correlate with MFS. We hypothesize that
radiographic parameters assessing hindfoot alignment are correlated with MFS.
Methods: Seventy-three feet diagnosed with PCFD were evaluated using WBR and WBCT. Five parameters were
measured in both modalities: talonavicular coverage (TNC) angle, hindfoot moment arm (HMA), talo–first metatarsal
angle, calcaneal pitch angle, and sinus tarsi impingement. MFS was then measured on WBCT. Multivariate and bivariate
regression analyses were used to identify which WBR measurements predict or correlate with MFS. Partition analysis was
used to identify cutoff values for WBR measurements linked with MFS.
Results: Multivariate regression identified TNC angle and HMA as combined MFS predictors (R² = 0.524, P < .0001). In the
bivariate analysis, TNC angle demonstrated a moderate individual correlation with MFS (r = 0.68), whereas HMA showed
a weak individual correlation (r = 0.39). Partition analysis identified practical radiographic thresholds (TNC angle ≥ 38
degrees, HMA ≥ 11.4 mm) for MFS ≥18% yet these thresholds explained only 27.3% of variability (R² = 0.273).
Conclusion: TNC angle and HMA are the most useful WBR measurements for identifying MFS in PCFD. In settings without
WBCT access, these offer a practical assessment tool, associated with MFS ≥18%; however, these cutoffs accounted for
only 27.3% of variance (R² = 0.273), underscoring residual unexplained factors.
Level of Evidence: Level III, retrospective comparative study.

Aims
Assessment of lower limb alignment is a cornerstone of orthopaedics. Few studies look
at rotational alignment in the axial plane as measured by femoral version (FV) and tibial
torsion (TT), both of which have implications for hip, knee, and ankle pathology. This
review provides an overview of the axial rotation and evaluates CT-b ased measurement
methods for FV and TT to identify the most reliable and reproducible techniques for use in
clinical practice.

Methods
A systematic PRISMA- guided review assessed original CT-b ased methods, examining
inter- and intraobserver reliability (intraclass correlation coefficient (ICC)), frequency of
use, and validation.

Results
Seven FV and nine TT CT- based techniques were identified. FV had a weighted mean of
17.8° anteversion (-9 ° to 60°). TT had a weighted mean of 30.8° (2° to 82°). ICCs ranged from
good to excellent. The Murphy method (FV) and Goutallier method (TT) had the highest
reliability and clinical utility.

Conclusion
Lower limb axial rotational profile plays an important role in the management of hip, knee,
and ankle arthroplasty surgery as well as many other orthopaedic pathologies. The Murphy
and Goutallier methods should be adopted as standard for measuring FV and TT. Their high
reproducibility and validation make them ideal for consistent clinical and research use.