Diagnostic Characteristics of Standard Radiographs and Magnetic Resonance Imaging of Ruptures of the Tibialis Posterior Tendon

Diagnostic efficacy of posterior tibialis tendon dysfunction: a systematic review of literature

OBJECTIVE

To perform a systematic review to examine the diagnostic accuracy of magnetic resonance imaging, ultrasonography, and radiography in the evaluation of posterior tibial tendon dysfunction (PTTD).

MATERIALS AND METHODS

Medline, Scopus, Embase, and The Cochrane Central Register of Controlled Trials (CENTRAL) were searched for relevant studies through April 2023. The study quality was assessed using the QUADAS-2 scoring system.

RESULTS

Of the initial 634 studies, 12 studies met the quality criteria and were included, with 645 PTTs evaluated with MRI, 133 with US, and 97 with radiography. MRI was found to be more sensitive and specific than ultrasound, radiography, and clinical evaluation for detecting PTTD, with a sensitivity of up to 95%, specificity of up to 100%, and accuracy of 96% for detecting PTT tears. US showed a sensitivity of 80% and specificity of 90% for diagnosing tendinopathy, and a sensitivity of 90% and specificity of 80% for diagnosing peritendinosis when compared to MRI. Weight-bearing radiographs had a sensitivity of 71.4%, specificity of 88.9%, and diagnostic accuracy of 81.3% when diagnosing PTT ruptures. Various radiologic measurements were also found to have a significant relationship with PTT tears but were poorly correlated with PTT tendinosis and isolated tenosynovitis.

CONCLUSION

Magnetic resonance imaging is the preferred imaging tool for evaluating patients with posterior tibial tendon dysfunction, with higher diagnostic accuracy, sensitivity, and specificity compared to ultrasound and radiographic imaging. However, initial imaging with ultrasound and radiographs may be used due to their availability and cost-effectiveness.

CLINICAL RELEVANCE

PTTD affects 3% of women ≥ 40 years and 10% of adults ≥ 65 years globally. Using the appropriate imaging study, MRI ensures that patients suffering from PTTD are diagnosed and treated in a timely manner.

KEY POINTS

• This review aimed to determine the diagnostic accuracy of MRI, ultrasonography, and radiography in evaluating PTTD. • MRI outperformed ultrasound and radiography, with higher sensitivity, specificity, and accuracy in detecting PTT tears. • MRI is the preferred imaging modality for the initial diagnosis of PTTD.

Tibial Retro-Malleolar Groove Morphology in Patients With Posterior Tibialis Tendon Dysfunction

The posterior tibial tendon is a gliding tendon which courses around the medial malleolus and fails in posterior tibialis tendon dysfunction (PTTD) leading to a flat foot deformity. Distal tibial bone spurs have been identified as a secondary sign of PTTD although they have not been quantified in detail. The aim of this study was to assess the association of tendon dysfunction with the bony morphology of the tibial retro-malleolar groove. We performed a retrospective review of the clinical presentation, plain radiographs, and 103 magnetic resonance imaging (MRI) scans in 82 consecutive patients with PTTD compared with a non-PTTD group. We carried out a quantitative and qualitative assessment of the presence of plain radiographic bone spurs, stage of PTTD and MRI imaging of the morphology of the tibial bony malleolar groove. Plain radiographic bone spurs, as a secondary sign of PTTD, were present in 21.3% of ankle radiographs. MRI bone spurs were identified in 26/41 (63.4%) for all high-grade partial and complete tears and 7/41 (17.1%) for isolated complete tears compared with only 3.9% of the non-PTTD group. There was a significant association between the presence of bone spurs on MRI imaging and high-grade partial and complete tibialis posterior tears (p < .001; odds ratio of 4.98). Eleven of 103 (10.7%) of spurs were large and in 4/103 (3.9%) were substantial enough to create a tunnel-like hypertrophic groove not previously reported. There is variation in the bony structure of the malleolar groove in PTTD not observed in the non-PTTD group. Further investigation over time may elucidate whether the groove morphology may lead to mechanical attrition of the tibialis posterior tendon and contribute to failure of healing and progressive tendon degeneration.

Understanding Radiographic Measurements Used in Foot and Ankle Surgery

Given the high volume of patient visits for foot and ankle complaints, developing a systematic approach to evaluation of foot and ankle pathology is important for orthopaedic providers. A thorough evaluation of weight-bearing radiographs is essential to differentiate acute and chronic injury from normal findings to dictate treatment. Radiographic changes and varying degrees of deformity can influence surgical considerations. The purpose of this article was to review and define radiographic measurements relevant to surgical decision making for common foot and ankle pathologies and treatment.

Is Advanced Imaging a Must in the Assessment of Progressive Collapsing Foot Deformity?

Advanced imaging modalities have, in very recent years, enabled a considerable leap in understanding progressive collapsing foot deformity, evolving from a simple confirmation of clinical diagnostic using basic measurements to minute understanding of soft tissue and bone involvements. MRI and weight-bearing cone-beam computed tomography are enabling the development of new 3-dimensional measurement modalities. The identification of key articular and joint markers of advanced collapse will allow surgeons to better indicate treatments and assess chances of success with conservative therapies and less invasive surgical procedures, with the hope of improving patient outcomes.

Reproducibility of radiographic methods for assessing longitudinal tarsal axes: Part 1: Consecutive case study

INTRODUCTION

Calcaneal pitch angle and Meary's angle are commonly used to assess longitudinal foot arches on lateral-view radiographs. However, the methods used to obtain the talar, first metatarsal, calcaneal, and plantar axes differ across multiple reports, and no study has evaluated the reproducibility of these approaches. The aim of this study was to determine the most reproducible methods for radiographically evaluating longitudinal axes.

METHODS

Standing radiographic images of 40 feet from 21 consecutive outpatients were obtained to measure longitudinal axes of the talus, first metatarsal, calcaneus and plantar surface, which were defined using six, five, four and three different methods, respectively, selected from previous reports. Intraobserver and interobserver correlation coefficients were calculated.

RESULTS

The best intraobserver and interobserver correlation coefficients for the talar, first metatarsal, and calcaneal axes were obtained using methods involving a line bisecting the angle formed by the lines tangential to the superior and inferior margins of the talus, a line connecting the centre of the first metatarsal head and the midpoint of the visualized base of the first metatarsal, and a line drawn tangential to the inferior surface of the calcaneus, respectively. For the plantar axis, a method that used the horizontal plane (as a reference axis) was regarded as the best approach, although intraobserver and interobserver correlation coefficients could not be calculated because all values were zero.

CONCLUSIONS

The aforementioned methods were considered to be optimal for the radiographic assessment of longitudinal foot arches. This study could contribute to more accurate assessments of foot deformities.