Atypical Presentation of Gout: Idiopathic Retrocalcaneal Pain in 400 Patients

Introduction: Idiopathic retrocalcaneal pain is frequently linked to overuse injuries or inflammation around the Achilles tendon and surrounding bursae. However, systemic conditions such as gout, characterized by monosodium urate crystal deposition, can also present as retrocalcaneal pain. Gout commonly affects the first metatarsophalangeal joint, but atypical presentations like retrocalcaneal involvement are increasingly recognized. This study aims to assess the presentation, diagnosis, and treatment outcomes of gout in patients presenting with idiopathic retrocalcaneal pain. Materials and Methods: This retrospective study analysed clinical data from 400 patients diagnosed with gout and presenting with idiopathic retrocalcaneal pain between 2019 and 2023 at a tertiary care centre. Diagnosis was based on clinical examination, serum uric acid levels, imaging, and in some cases, synovial fluid analysis. Patient demographics, diagnostic methods, and treatment outcomes, including pain (VAS) and functionality (FADI) scores, were evaluated. Results: Of the 400 patients, 290 (72.5%) were male, and 110 (27.5%) were female, with a mean age of 56.8 ± 12.3 years. Pre-existing gout was present in 58% of patients, and serum uric acid levels were elevated in 75%. Synovial fluid analysis, performed in 65 patients, confirmed monosodium urate crystals in 92.3% of cases. Treatment resulted in significant reductions in pain (VAS: 7.8 ± 1.4 to 3.2 ± 1.1, p < 0.05) and improved functionality (FADI: 58.4 ± 5.7 to 85.7 ± 6.3). Recurrence of symptoms occurred in 25% of patients, particularly in those who did not adhere to urate-lowering therapy. Conclusion: This study emphasizes the importance of considering gout in the differential diagnosis of idiopathic retrocalcaneal pain. Early diagnosis and appropriate management can lead to favourable outcomes and lower recurrence rates. Clinicians should remain vigilant for atypical presentations of gout to prevent prolonged discomfort and functional impairment. Keywords: Idiopathic retrocalcaneal pain, gout, hyperuricemia, monosodium urate crystals, Achilles tendon, atypical gout, urate-lowering therapy