(1) Generate empirical knowledge of a Musculoskeletal (MSK) Advanced Practice Physiotherapist (APP) Service in Scottish Primary Care; (2) Identify the incidence and baseline time to diagnosis of Axial Spondyloarthropathy (AxSpA); (3) Identify APP Rheumatology referral fulfilment of the NICE 2017 Guidelines and Spondylarthritis Diagnosis Evaluation (SPADE) Tool; (4) Calculate APP Rheumatology referral conversion rates for AxSpA diagnosis and further investigation; (5) Contribute towards the current body of literature for informing analysis of MSK APP services within Scottish Primary Care. An audit and evaluation approach was undertaken over a 3-year period (May 2019-April 2022). Relevant clinical cases from the whole-service data-set were identified and analysed, using retrospective electronic healthcare record review and descriptive statistical techniques. A total of 37,656 primary care MSK APP consultations took place, with N=19 suspected AxSpA referrals made to Rheumatology. N=6 cases of AxSpA were diagnosed by a Rheumatologist (31.6%). The mean age of individuals diagnosed with AxSpA was 39.6±8.8, and 66.7% (4/6) were female. Mean time to diagnosis was 3.4years, and incidence per-10,000 person-years was 1.6. Compliance of referrals with the NICE 2017 Guidelines and SPADE Tool Criteria was 78.9%. Of those diagnosed with AxSpA, 66.7% met both referral criterion sets. Those referred by an MSK APP from primary care had a 5.1year shorter time to diagnosis than the previous reported UK average of 8.5years. APPs identified relevant AxSpA features in referring to Rheumatology, and supported effective implementation of the local secondary care pathway.