A 35-year-old patient presents with complaints of low back pain that has been progressively worsening over the past few weeks. The pain radiates to the groin and anterior thigh. The patient reports a history of prolonged sitting due to work. On physical examination, the patient exhibits an antalgic gait and tenderness to palpation over the lumbar paraspinals. There is also a positive Thomas test. Based on the patient’s history and examination findings, what is the most likely diagnosis?