MRI Evaluation of Traumatic and Non-traumatic Pathologies of the Ankle Joint and Hindfoot: A Single-Center Observational Study

Background Pathologies affecting the ankle joint and hindfoot can present with a variety of clinical symptoms and etiologies, necessitating accurate diagnostic tools for effective management. Magnetic resonance imaging (MRI) is a valuable imaging modality for assessing these pathologies, providing detailed visualization of bone, joint, tendon, and other soft tissue abnormalities. Objectives To evaluate MRI findings in a diverse cohort of 105 participants with pathologies affecting the ankle joint and hindfoot, focusing on the prevalence and types of bone, joint, tendon, and soft tissue abnormalities. Materials and methods A single-center observational descriptive study was conducted at Dr. D. Y. Patil Medical College and Hospital and Research Centre, Pune, India, over a period from August 2022 to July 2024, involving 105 participants (54.3% male, 45.7% female) with a mean age of 39.04 years. MRI scans were analyzed to assess the prevalence of bone, joint, tendon, and soft tissue pathologies. Clinical profiles, symptom duration, and etiological classifications were documented. Results Analysis of the results obtained from 105 (N = 105) study participants revealed that pain (94.3%, or 99 cases) was the most common symptom, followed by restricted movement (86.7%, or 91 cases), trauma history (75.2%, or 79 cases), and swelling (73.3%, or 77 cases). Traumatic causes (76.2%, or 80 cases) predominated, while inflammatory (48.3%, or 14 cases) and infective (34.5%, or 10 cases) causes were also significant. MRI findings showed marrow edema in 41.9%, or 44 cases, subchondral cysts in 22.9% (24 cases), fractures in 17.1% (18 cases), and erosions in 10.5% of participants (11 cases). Joint involvement was most frequent in the tibiotalar (76.2%, or 80 cases) and subtalar joints (58.1%, or 61 cases). Tendon pathologies included peritendonitis (55.2%, or 58 cases) and tendinosis (23.8%, or 25 cases), with the Achilles tendon being the most frequently affected (39%, or 41 cases). Ligament injuries were predominantly sprains (46.7%, or 49 cases), with less frequent partial (18.1%, or 19 cases) and complete tears (7.6%, or eight cases). Soft tissue findings included subcutaneous edema (76.2%, or 80 cases) and bursitis (24.8%, or 26 cases). Among the study participants who presented with non-traumatic pathologies, inflammatory pathologies (48.3%, or 14 cases) were the most common, followed by infective (34.5%, or 10 cases) and neoplastic (17.2%, or five cases) pathologies. Conclusion MRI effectively identifies a wide range of pathologies in the ankle and hindfoot, with marrow edema, joint effusion, and tendon pathologies being prevalent. The study underscores the utility of MRI in diagnosing and assessing various conditions in the ankle joint complex and highlights the need for accurate imaging to guide treatment decisions. Future research should focus on correlating MRI findings with clinical outcomes to enhance diagnostic accuracy and management strategies.


Introduction
Magnetic resonance imaging (MRI) is highly effective in promptly identifying and evaluating various bone abnormalities, including stress fractures, bone contusions, osteochondral fractures, transient bone marrow edema, and osteonecrosis [1].
The ankle joint and hindfoot are crucial anatomical regions subjected to significant mechanical stress, often leading to a variety of traumatic and non-traumatic pathologies.These areas play a pivotal role in mobility, bearing weight, and providing balance, making them susceptible to injuries and degenerative conditions [2].MRI has emerged as an invaluable tool in the diagnostic evaluation of these pathologies, due to its superior soft tissue contrast and multiplanar imaging capabilities [3].
Traumatic injuries to the ankle joint and hindfoot are common, especially among athletes and individuals engaged in physical activities.These injuries can range from ligament sprains and tendon tears to fractures and dislocations.Accurate and timely diagnosis is essential to guide appropriate management and rehabilitation, preventing long-term complications and ensuring optimal functional recovery [4].MRI's ability to visualize soft tissues, cartilage, and bone marrow in detail makes it the modality of choice for detecting subtle injuries that may not be apparent on conventional radiographs [3].
Non-traumatic pathologies of the ankle and hindfoot, such as osteoarthritis, rheumatoid arthritis, and congenital deformities, also pose significant challenges in clinical practice.These conditions often lead to chronic pain, stiffness, and functional impairment, impacting the quality of life [5].MRI is particularly useful in identifying early degenerative changes, inflammatory processes, and other subtle abnormalities, allowing for early intervention and improved patient outcomes [6].
The anatomy of the ankle joint and hindfoot is complex, comprising bones, ligaments, tendons, and other soft tissue structures.A thorough understanding of this anatomy is essential for accurate interpretation of MRI findings [2].The ankle joint includes the tibiotalar, subtalar, and transverse tarsal joints, each with specific biomechanical functions.Ligamentous structures, such as the lateral collateral ligaments, medial collateral ligaments, and syndesmotic ligaments, provide stability, while tendons, including the Achilles tendon, facilitate movement [7].
The biomechanics of the ankle joint further complicate the diagnostic evaluation of pathologies [8].The ankle joint permits dorsiflexion and plantar flexion, while the subtalar joint allows for inversion and eversion movements.Stability is maintained through the intricate interplay of ligamentous and tendinous structures, and any disruption can lead to significant functional impairment.Understanding these biomechanical principles is crucial for identifying the underlying causes of pain and dysfunction in the ankle and hindfoot [9].The medial collateral ligament, or deltoid ligament complex, is the principal ankle ligament responsible for stabilizing the ankle when it is subjected to axial loading.It has five bands -the anterior and posterior tibiotalar, tibiospring, tibiocalcaneal, and tibionavicular ligaments.Injury to this structure is quite rare and occurs in just 5% of cases of ankle sprains [10].
Ankle sprains are anatomically classified according to the number of ligaments that are affected.A complete or partial tear of the anterior talofibular ligament (ATFL) characterizes a first-degree sprain.A partial or full tear of the ATFL, as well as the calcaneofibular ligament (CFL), characterizes a second-degree sprain.CFL, ATFL, and posterior talofibular ligament (PTFL) are all involved in third-degree sprains [11].
Among the prevalent infectious pathologies, MRI is the preferred modality for early detection of joint tuberculosis.Musculoskeletal tuberculosis affects 1-3% of patients with TB, with axial skeletal involvement being more frequent.Peripheral arthritis is reported in approximately 60% of cases, while osteomyelitis occurs in about 38% of cases [12].Tuberculous osteomyelitis is more common in the bones of the extremities.Changes in the bone marrow are visualized as regions of decreased and increased signal intensity on T1-weighted and T2-weighted images, respectively, and exhibit notable enhancement after contrast administration.Deep soft tissue alterations, such as sinus tracts or abscess formation, are more effectively depicted on gadolinium-enhanced images [13].
The literature reveals extensive use of MRI in diagnosing ankle joint and hindfoot pathologies.Numerous studies have demonstrated MRI's superiority in detecting both acute injuries and chronic conditions, often leading to changes in clinical management.By compiling and analyzing existing research, this paper underscores the importance of MRI in the diagnostic process and its impact on treatment outcomes.Through a comprehensive review of traumatic and non-traumatic pathologies, this study aims to highlight the indispensable role of MRI in modern clinical practice, ultimately contributing to better patient care and outcomes [3,6].
The objective of this study is to evaluate MRI findings in a diverse cohort of 105 participants with pathologies affecting the ankle joint and hindfoot, with a focus on the prevalence and classification of bone, joint, tendon, and soft tissue abnormalities on MRI.

Technical protocols
The MRI sequences employed are shown in Table 1.

Statistical analysis
Data were collected and recorded over a two-year period and subsequently analyzed using Microsoft Excel (Microsoft® Corp., Redmond, WA, USA) and IBM SPSS Statistics for Windows, Version 26.0 (Released 2019; IBM Corp., Armonk, NY, USA).Categorical variables were summarized using frequencies and proportions, while continuous variables were analyzed with means and standard deviations.

Results
The study comprised 105 participants, of whom 57 were male (54.3%) and 48 were female (45.7%).The age distribution was diverse, with the majority of participants falling within the 21-30 age group (28.6%), followed by the 31-40 age group (23.8%) (   The etiological classification revealed that traumatic causes were predominant, accounting for 76.2% of cases.Among the non-traumatic causes, inflammatory pathologies were the most common (48.3%, or 14 cases), followed by infective causes (34.5%, or 10 cases) and neoplastic causes (17.2%, or five cases).
Regarding non-traumatic pathologies, the most frequently observed conditions were inflammatory (48.3%, or 14 cases) and infective (34.5%, or 10 cases), with neoplastic causes being less common (17.2%, or five cases).This data emphasizes the importance of differentiating between various non-traumatic conditions to  4).

Non-traumatic cause of lesion Frequency (N = 29) Percentage
Infective   The most common MRI finding in patients with bone involvement was marrow edema, identified in 44 cases, which represents 41.9% of the study population.Subchondral or intraosseous cysts were found in 24 cases, or 22.9%.Fractures and erosions were also relatively common, observed in 18 (17.1%)and 11 (10.5%)cases, respectively.Contusions were noted in nine cases (8.6%), while serpiginous areas of altered signal intensity and subchondral compression were less frequent, appearing in two cases (1.9%) and one case (1%), respectively.Other findings, such as the Stieda process, osteophytes, and sclerotic lesions, were observed in eight cases (7.6%), eight cases (7.6%), and one case (1%), respectively.Neoplastic lesions, periosteal reactions/periostitis, sequestrum, abscess, and apophysitis were among the least common findings, each noted in fewer cases (  We further analyzed the joint involvement among the participants (Table 7).The tibiotalar joint was the most frequently affected, with abnormalities observed in 76.2% (80 cases) of the participants, followed by the subtalar joint (talocalcaneal), with 58.1% (61 cases) of participants showing abnormalities.Other joints showed less frequent involvement.The distal tibiofibular joint was affected in 20% (21 cases) of participants, reflecting its role in ankle syndesmosis injuries.The talonavicular joint had a 9.5% (10 cases) involvement rate, which is important for the flexibility and movement of the midfoot.Less common joint involvements included the calcaneonavicular joint (5.7%, or six cases), the calcaneocuboid joint (4.8%, or five cases), the cuneonavicular joint (4.8%, or five cases), and the tarsometatarsal joint (  The MRI findings in the patients with joint involvement showed that effusion was the most prevalent finding, present in 86 cases, or 81.9% of the sample.Reduced joint space was observed in 12 cases (11.4%).Synovial thickening was noted in 14 cases (13.3%), while subchondral erosions and cartilage loss were found in 10 (9.5%) and nine (8.6%) cases, respectively.Dislocations and loose bodies each appeared in four cases (3.8%).Periarticular collections were seen in three cases (2.9%), and synovial cysts were the least common, present in just one case (1%) (Table 8).We also studied the tendons involved.The Achilles tendon was the most frequently observed, with 41 cases, representing 39% of the total.The tibialis posterior tendon followed closely, with 45 cases, accounting for 42.9%.Flexor tendons were also notably prevalent, appearing in 40 cases, or 38.1% of the study.In contrast, the tibialis anterior tendon was the least frequently observed, with only four cases, making up just 3.8%.The extensor tendons were seen in 11 cases, equating to 10.5%, while the peroneus tendons were present in 34 cases, which is 32.4% of the total (Table 9).The MRI findings in study participants with tendon involvement showed that peritendonitis or tenosynovitis was the most frequently observed condition, present in 58 cases, which accounts for 55.2% of the study population.Tendinosis was also relatively common, found in 25 cases (23.8%).Partial tears were noted in 12 cases (11.4%), while complete tears were less frequent, occurring in seven cases (6.7%).Hematomas, ganglion cysts, abscesses, and encased tendons were among the least common findings, each observed in one to three cases, representing between 1% and 2.9% of the total (Table 10).

MRI findings* Frequency (N = 105) Percentage
Peritendonitis  The CFL was the most frequently involved, seen in 91 cases, which constitutes 86.7% of the study sample.
The PTFL and ATFL were also commonly injured, with 39 (37.1%) and 37 (35.2%)cases, respectively.Involvement of the deltoid complex was seen in 15 cases, representing 14.3% of the sample.Pathologies of the posterior inferior tibiofibular ligament and the spring (calcaneonavicular) ligament were observed in 10 (9.5%) and seven (6.7%) cases each, respectively.The anterior inferior tibiofibular ligament was involved in seven cases (6.7%).Involvement of other ligaments, including the tibiocalcaneal, dorsal talonavicular, calcaneofibular, dorsal calcaneocuboid, and tibionavicular, was seen in very few cases, ranging from one to three cases each, indicating their relatively lower prevalence in the study (Table 11).The most frequently identified finding in the patients with ligament involvement was sprain, observed in 49 cases, which accounts for 46.7% of the study population.Partial tears were noted in 19 cases (18.1%), while complete tears were found in eight cases (7.6%).This distribution highlights sprains as the predominant type of ligament injury among the cases studied, with partial and complete tears being less common.The involvement of the soft tissue was also analyzed in this study (Table 12).Subcutaneous tissue and skin were the most commonly affected, each observed in 79 cases, representing 75.2% of the sample.The retrocalcaneal bursa and Kager fat pad were also frequently involved, appearing in 26 (24.8%) and 16 (15.2%)cases, respectively.The calcaneal spur was seen in 18 cases (17.1%).In contrast, other soft tissues had much lower prevalence rates: the plantar fascia was involved in eight cases (7.6%), and the flexor hallucis longus muscle in nine cases (8.6%).Muscles such as the tibialis posterior, peroneus brevis, flexor hallucis brevis, extensor hallucis longus, and flexor digitorum longus were affected in one to five cases each, representing between 1% and 4.8%, indicating less frequent involvement.
Frequency (N = 105)  The MRI findings in participants with soft tissue involvement (Table 13) reveal that edema was the most common finding, present in 80 cases, which constitutes 76.2% of those with soft tissue issues.Bursitis was the next most frequent, identified in 26 cases, or 24.8%.Other notable findings included ulceration in nine cases (8.6%) and thickening in 11 cases (10.5%).Both abscesses and myositis/muscle edema were observed in seven cases each, representing 6.7% of the participants.Neoplastic lesions were found in three cases (2.9%), while muscle strain was the least common finding, seen in just one case (1.0%).Notably, there were no instances of foreign bodies or cystic lesions.Although the prevalence of fractures across both studies was comparable, the prevalence of contusions observed on MRI in Turky et al.'s study was significantly higher.Nearly 55 study participants (91.7%) exhibited joint effusion, while 11 (18.3%)showed symptoms of sinus tarsi syndrome in the previous study [14].In the current study, 81.9% of the study participants showed joint effusion, and only four cases (3.8%) showed findings of sinus tarsi syndrome.The higher proportion of contusions, joint effusion, and sinus tarsi syndrome in Turky et al.'s study is probably due to the inclusion of only patients with post-traumatic ankle joint pathology.

MRI findings*
Sayed et al. studied 50 patients with severe ankle pain in 2021.Among them, 28% were found to have ligament tears, with the ATFL being the most frequently torn.The study also observed Achilles pathology (14%), retrocalcaneal bursitis (4%), and various osseous lesions in 54% of patients.Bone marrow edema was observed in 32% of cases [17].The present study revealed that 35.2% of cases had an ATFL, 25% had bursitis, and 41.9% had marrow edema.The prevalence of deltoid pathology observed in the previous study (12%) was similar to the findings of the current study.
In 2021, Bajwa et al. conducted an observational study among 61 participants, with the majority in the younger age group of 21-30 years (27.87%).Half of them had trauma.Twelve participants exhibited MRI evidence of infection, while five revealed neoplastic pathologies [18].In the present study, among the nontraumatic lesions, 48% were due to inflammatory etiology, 34% were attributed to infective causes, and the remaining 17% were neoplastic.The prevalence of neoplastic and inflammatory etiologies in the present study was higher than in the Bajwa et al. study.
Although the present study contributes valuable insights to the field, it has several limitations.The relatively small sample size may not be representative of broader populations.Additionally, the study lacks long-term follow-up data on the progression of the pathology, its treatment, and outcomes.The inclusion of both traumatic and non-traumatic lesions may complicate the findings, and potential confounding factors, such as pre-existing conditions, could not be fully controlled.

Conclusions
MRI excels in diagnosing ankle and hindfoot pathologies due to its superior soft tissue contrast, surpassing conventional radiography and CT in detecting tendon, ligament, and osseous abnormalities.It effectively identifies conditions such as osteomyelitis, plantar fasciitis, and neoplasms, which are generally benign.MRI is crucial for evaluating injuries, particularly to the lateral ankle ligaments and Achilles tendon, and is essential for diagnosing trauma-related osteoarthritis.This study highlights the frequent involvement of the talus and calcaneum, with the tibiotalar and subtalar joints being the most affected.Future research should focus on correlating MRI findings with intraoperative observations to assess diagnostic accuracy.
declared that there are no other relationships or activities that could appear to have influenced the submitted work.
Published via Dr. D Y Patil Medical College, Hospital and Research Centre, Dr. D Y Patil Vidyapeeth (Deemed to be University), Pune ensure appropriate diagnosis and treatment (Table

TABLE 1 : MRI sequences employed
WI: Weighted imaging; FSE: Fast spin echo; STIR: Sagittal short tau inversion recovery; PDFS: Proton density fat suppression; TR: Repetition time; TE: Time to echo; FoV: Field of view; GRE: Gradient echo; FS: Fat suppression

Table 2
).The mean age of the participants was 39.04 years, with a standard deviation of 18.77 years.Percentage

TABLE 2 : Distribution of study participants on the basis of age
The clinical profile of the study participants showed that pain was the most common symptom, reported by 94.3% (99 cases) of the participants.Other prevalent symptoms included restricted movement (86.7%, or 91 cases), history of trauma (75.2%, or 79 cases), and swelling (73.3%, or 77 cases).Less common symptoms included twisting injuries (34.3%, or 36 cases), fall from height (19%, or 20 cases), and discharging sinus (10.5%, or 11 cases) (Table3).The duration of symptoms varied, with 31.4% (33 participants) experiencing acute symptoms (less than or equal to four weeks) and 68.6% (72 participants) experiencing chronic symptoms (more than four weeks).

TABLE 3 : Clinical profile of study participants
* Multiple responses for each study participant allowed

TABLE 4 : Distribution of non-traumatic pathologies among study participants
Includes infections and inflammatory pathologies following a history of traumaThe MRI findings in this study revealed significant involvement of various bones in the ankle joint and hindfoot, underscoring the importance of MRI in identifying osseous abnormalities.The talus was the most frequently involved bone, with abnormalities detected in 41% of participants, highlighting its central role in ankle joint mechanics and the common occurrence of talar pathologies.The calcaneum, or heel bone, was the second most commonly affected, observed in 29.5%, or 31 cases, indicating the prevalence of calcaneal injuries that often result in heel pain and mobility issues.The lower tibia and lower fibula were also notably affected, found in 21% (22 cases) and 15.2% (16 cases) of participants, respectively, underscoring their susceptibility to both traumatic and non-traumatic pathologies.Less commonly involved bones included the navicular (4.8%, or five cases), cuboid (5.7%, or six cases), and cuneiform (6.7%, or seven cases), each playing critical roles in foot stability and function.Additionally, accessory ossicles were identified in 3.8%, or four cases, which, although often asymptomatic, can sometimes cause pain and require precise diagnosis (Table5). *

TABLE 5 : Bone involvement among study participants
* Multiple responses for each study participant allowed

TABLE 6 : MRI findings in study participants with bone involvement
* Multiple responses for each study participant allowed

TABLE 7 : Joint involvement among study participants
* Multiple responses for each study participant allowed

TABLE 8 : MRI findings in study participants with joint involvement
* Multiple responses for each study participant allowed

TABLE 9 : Tendon involvement among study participants
* Multiple responses for each study participant allowed

TABLE 10 : MRI findings in study participants with tendon involvement
* Multiple responses for each study participant allowed

TABLE 11 : Ligament involvement among study participants
* Multiple responses for each study participant allowed

TABLE 12 : Soft tissue involvement among study participants
* Multiple responses for each study participant allowed