Low back pain is one of the most commonly treated conditions by outpatient orthopedic physical therapists. The management of low back pain is also responsible for a large economic burden in the United States and internationally, which highlights one of the many reasons why appropriate medical screening and referral is important in the physical therapy setting. The purpose of this case report is to describe the successful physical therapist screening and subsequent medical differential diagnosis of a 36- year-old male with chronic lower back and toe pain. Initial physical therapy evaluation supported a diagnosis of mechanical low back pain, but symptom progression through two treatment sessions indicated that a non-mechanical source of pain was instead the likely cause of the patient's symptoms. The referring physician was contacted by the physical therapist and the patient was scheduled for further medical examination. A consult to rheumatology was placed and through compilation of clinical, laboratory, and imaging findings, a diagnosis of human leukocyte antigen B-27-positive spondyloarthropathy was made. Even with physician referral, it is imperative for clinicians to be proficient in screening for non-mechanical low back pain that may mimic a musculoskeletal origin of symptoms.
Keywords: Medical screening; Non-mechanical back pain; Physical therapy; Psoriatic arthritis; Spondyloarthropathy.