One hundred and forty-five patients with subacromial pain syndrome (SAPS) who were complaining of anterolateral shoulder pain for >6 weeks and had a positive Neer impingement test were randomized to undergo spinal thrust manipulation and electrical dry needling (TMEDN) (n=73) or non-thrust peripheral joint/soft tissue mobilization, exercise, and interferential current (NTMEX) (n=72). Primary outcomes of interest included pain measured with a numeric pain-rating scale (NPRS) and disability measured using the shoulder pain and disability index (SPADI). Secondary outcomes of interest included the global rating of change scale (GROC), as well as medication consumption. The incidence of adverse events was also measured. All outcomes were measured at 2 weeks, 4 weeks, and 3 months follow-up. Results demonstrated that both disability and pain were statistically significantly improved in the TMEDN group at all timepoints compared to the NTMEX group (p<0.05 for all). No adverse events were observed in either groups. 74% of patients in the TMEDN group and 32% in the NTMEX group stopped taking pain medication at 3 months follow-up which was statistically significantly in favour of the TMEDN group (p<0.001). Moreover, 71% of patients in the TMEDN group and 25% of patients in the NTMEX group achieved the cutoff score of +5 for GROC at 3 months follow-up, which was statistically significantly in favour of the TMEDN group (p<0.001). Furthermore, patients in the TMEDN group experienced muscle soreness after administering the needle (n=37; 50.1%), mild bruising (n=15; 20.5%), and drowsiness/headache/nausea (n=2; 2.7%).