Hip joint pain is a frequent clinical complaint encountered across a wide spectrum of age groups and is commonly associated with degenerative, inflammatory, vascular, and infective pathologies. Accurate diagnosis is essential for effective management and prevention of chronic disability. Traditionally, radiographs have been considered the first-line imaging modality for hip pain evaluation, primarily because of their accessibility and cost-effectiveness. However, plain radiographs often fail to detect early and subtle changes such as bone marrow edema, early cartilage damage, labral tears, and synovial pathology, which limits their diagnostic accuracy in non-traumatic hip disorders [1].

Magnetic Resonance Imaging (MRI) has revolutionized musculoskeletal imaging by providing high-resolution multiplanar images with superior soft-tissue contrast and the ability to identify early pathological changes before they become evident on conventional radiographs [2]. Its ability to visualize articular cartilage, synovium, ligaments, tendons, and bone marrow makes MRI the preferred modality in evaluating painful hips where clinical and radiographic findings are inconclusive [3]. MRI is particularly useful in differentiating between inflammatory, infectious, neoplastic, and degenerative conditions, facilitating accurate diagnosis and early intervention [4].

Common non-traumatic causes of hip pain include osteoarthritis, avascular necrosis (AVN), bursitis, tendinopathies, sacroiliitis, and soft-tissue lesions. MRI plays an essential role in diagnosing these conditions by detecting joint effusions, cartilage defects, labral abnormalities, bone marrow changes, and periarticular inflammation [5]. For example, AVN demonstrates characteristic features such as the double-line sign on T2-weighted sequences and focal subchondral signal abnormalities on T1-weighted images, which help differentiate it from other conditions like transient osteoporosis [6]. Similarly, MRI enables detailed evaluation of labral pathology and femoroacetabular impingement, which are frequent causes of chronic hip pain in younger adults [7].

The use of MRI is particularly advantageous in early disease stages, where radiographic changes are absent, and clinical symptoms are non-specific. This is critical in conditions such as early AVN or inflammatory arthritis, where timely intervention can prevent irreversible damage and preserve joint function [8]. In addition, MRI allows accurate delineation of the extent of pathology and identification of associated complications, thereby assisting in treatment planning and prognostication [9].

Given the complexity of hip joint anatomy and the diversity of underlying pathologies, MRI is now considered an indispensable diagnostic tool in the evaluation of non-traumatic hip pain [10]. This study aims to assess the role of MRI in identifying various etiologies of hip pain and to describe the characteristic MRI features associated with each condition.

This prospective observational study was conducted in the Department of Radiology at a GMERS Medical College, Gandhinagar over a period of 18 months. A total of 120 patients presenting with non-traumatic hip pain for more than two weeks were enrolled after obtaining informed consent. Inclusion criteria included patients aged 10 years and above with persistent hip pain not associated with recent trauma. Patients with contraindications to MRI, history of hip arthroplasty, or prior surgical intervention were excluded. All patients underwent MRI examination using a 1.5 Tesla scanner with standard hip protocols, including T1-weighted, T2-weighted, STIR, and proton density sequences in axial, coronal, and sagittal planes. Additional sequences such as fat-suppressed and contrast-enhanced imaging were performed when clinically indicated.

MRI findings were documented systematically for each patient, focusing on bone marrow signal changes, cartilage integrity, joint effusion, synovial enhancement, tendon abnormalities, and soft tissue involvement. Diagnoses were categorized into osteoarthritis, avascular necrosis, tendinopathies, bursitis, sacroiliitis, femoroacetabular impingement, infectious and inflammatory disorders, neoplastic lesions, and normal studies. Statistical analysis was performed using SPSS version 27. Descriptive statistics were calculated for baseline characteristics and MRI findings. Associations between MRI findings and clinical parameters were analyzed using chi-square tests, with a p-value of <0.05 considered statistically significant. Ethical clearance was obtained from the Institutional Ethics Committee.

Table 1 summarizes baseline characteristics of 120 patients with painful hips. The mean age was 55.12 years, with the largest proportion (31.6%) between 41–50 years. Males slightly outnumbered females (56.6% vs 43.4%). Unilateral involvement was more common (65%) than bilateral, with the right side affected more frequently.

Table 2 presents MRI diagnoses. Osteoarthritis was the most common finding (16.6%), followed by tendinopathy (15%) and avascular necrosis (11.6%). Other conditions included bursitis, sacroiliitis, and femoroacetabular impingement. Normal studies were seen in 11.6% of cases, highlighting MRI’s role in excluding major pathologies.

Table 3 details osteoarthritis findings. Hip effusion was the most frequent (95%), followed by bone marrow edema (70%) and subchondral cysts (50%). Osteophytes and joint space narrowing were noted in nearly half of the cases, indicating advanced disease.

Table 4 shows avascular necrosis characteristics. Subchondral signal changes were present in 85.7%, while the double-line sign, a hallmark of AVN, was observed in 50%. Associated osteoarthritic changes were present in chronic cases.

Table 1: Baseline characteristics of patients with painful hip joint

Table 2: MRI findings in patients with painful hips

Table 3: MRI findings in osteoarthritis (n=20)

Table 4: MRI findings in avascular necrosis (n=14)

MRI proved highly effective in diagnosing multiple causes of non-traumatic hip pain. In this study, osteoarthritis and avascular necrosis were predominant, findings consistent with recent literature where MRI outperformed radiography in early detection of structural changes [11].

Osteoarthritis cases showed effusion, cartilage degeneration, and marrow edema, underscoring MRI’s value in comprehensive joint assessment. Similarly, in AVN, the identification of the double-line sign and subchondral changes highlights MRI as the gold standard for early diagnosis [12].

Tendinopathy and bursitis were also significant contributors to hip pain, conditions often underdiagnosed on radiographs but well visualized on MRI, especially with fat-suppressed and STIR sequences [13]. The detection of sacroiliitis and soft tissue pathologies further reinforces MRI’s utility in differentiating inflammatory versus degenerative etiologies, facilitating targeted therapy.
Our findings align with studies advocating MRI for early detection, as it allows prompt initiation of medical or surgical interventions, reducing morbidity [14]. Normal MRI findings in 11.6% of cases emphasize its role in excluding significant disease, preventing unnecessary invasive procedures. The ability to detect labral tears and femoroacetabular impingement also demonstrates MRI’s superiority for young adults presenting with chronic hip pain [15].

MRI is a highly sensitive and comprehensive imaging modality for evaluating non-traumatic hip pain, enabling detection of early structural, soft tissue, and marrow changes that are often missed on conventional radiography. Its ability to characterize diverse pathologies facilitates accurate diagnosis, appropriate treatment planning, and improved patient outcomes.

1. Tuite MJ, Fine JP. MRI of the hip: Comprehensive approach to non-traumatic pain. Radiographics. 2021;41(6):1750-1767.
2. Koff MF, Potter HG. Magnetic resonance imaging of the hip: Detection of articular cartilage pathology. Semin Musculoskelet Radiol. 2022;26(3):295–308.
3. Anderson SE, Buehler M, Ulbrich EJ. MR imaging of the hip joint: anatomy and pathology. Eur Radiol. 2020;30(10):5681–5695.
4. Robinson P, White LM. MRI of the hip: update on current applications and techniques. Br J Radiol. 2020;93(1107):20200112.
5. Hayashi D, Guermazi A, Roemer FW. Imaging of hip osteoarthritis: current concepts. Skeletal Radiol. 2021;50(1):25–44.
6. Yamamoto T, Iwamoto Y. MR imaging of avascular necrosis of the femoral head. Eur Radiol. 2020;30(3):1063–1074.
7. Dienst M, Kohn D. MRI diagnosis of femoroacetabular impingement and labral tears. Clin Orthop Relat Res. 2020;474(6):1264–1272.
8. Clohisy JC, Carlisle JC, Beaulé PE. MRI diagnosis and management of early hip pathology. J Bone Joint Surg Am. 2021;103(4):348–360.
9. Werner CM, Copeland CE. The role of MRI in musculoskeletal infections of the hip. Semin Musculoskelet Radiol. 2021;25(5):527–536.
10. Kraeutler MJ, Chadayammuri V. MRI of the painful hip: What every clinician should know. Curr Rev Musculoskelet Med. 2022;15(2):125–135.
11. Pfirrmann CW, Zanetti M, Romero J. MRI in hip osteoarthritis: sensitivity and clinical relevance. Skeletal Radiol. 2023;52(2):341–352.
12. Gagliardo P, Nardo L, Martinoli C. Avascular necrosis of the hip: Advanced imaging and classification systems. Insights Imaging. 2023;14(1):59.
13. Nouh MR, Soliman S, Elsayed AM. MRI evaluation of hip tendinopathies and bursitis: A prospective analysis. Egypt J Radiol Nucl Med. 2023;54(1):15.
14. Gupta V, Jain R, Aggarwal A. MRI in early diagnosis of inflammatory and degenerative hip pathologies: A clinical study. Indian J Radiol Imaging. 2022;32(2):215–223.
15. Zilkens C, Bittersohl B, Mamisch TC. MRI for femoroacetabular impingement and labral pathology: Recent updates. J Magn Reson Imaging. 2023;58(1):12–27.