Background and Purpose: There have been few published studies regarding the treatment of patients with non-ossifying fibromas (NOFs), either conservatively or operatively. The purpose of this case report is to discuss the clinical presentation and conservative management of a teenage athlete diagnosed with a proximal humerus NOF. Case Description:The subject was a 13-year-old male middle school student with a diagnosis of left shoulder pain over the prior year preventing him from participating in sports activities. The combination of radiological findings revealing a NOF and a thorough physical examination allowed for the development of a physical therapy plan of care to address impairments and functional limitations. The subject was seen for eight visits where a combination of manual therapy techniques, neural mobilizations, and therapeutic exercises were administered to the cervical and upper quarter regions. The subject's progress was tracked by measuring pain-free shoulder active range of motion (AROM) and monitoring changes using the Numerical Pain Rating Scale (NRPS) values throughout sessions.Outcomes: After four sessions, AROM shoulder flexion and abduction increased from 123º and 119º to 160º and 180º respectively, and worst NRPS decreased from 9/10 to 3/10. Upon discharge after the eighth visit, the subject's DASH improved from 11.66 to 2.5. The subject remained pain free at an eight month follow up and returned to activity. Discussion: Thorough assessment of both neuromechanical sensitivity and musculoskeletal impairments may provide for the utilization of conservative treatment options for individuals with symptomatic NOFs.