Vira Simhavaloka · by Virasimha
Chapter 40 · Urustambha and Amavata: past deeds
ऊरुस्तंभ-आमवात — कर्मविपाकः
ऊरुस्तंभामवातोपसृष्टस्य कर्मविपाकमाह हुताग्निनिर्वापक आमवातवान् इति स्मरणात् तदुक्तदोषोपशांतयेऽयुतसंख्याको गायत्र्या जपस्तिलैराज्येन च होमः सुवर्णान्नदानम् ॥
The text tells the past-deed cause for one struck by urustambha (stiff thighs) and amavata (joint pain). This comes from a saying of the Smriti (law book). One who put out a fire kept alive for rites may get amavata. To ease the dosha (fault) so told, he should do japa (repeating a mantra) ten thousand times. The japa is of the Gayatri (gayatri mantra). He should do homa (fire offering) with sesame and clarified butter. He should give gold and food.
Classical view, not medical advice.