Comparison of clinical, radiological and functional outcomes of screw proximal femoral nail (PFN) and helical PFN in management of unstable trochanteric fractures. Methods: This prospective randomised comparative study included 60 patients with closed unstable intertrochanteric fractures (AO classification-A2.2eA2.3 & A3.1eA3.3). Patients were randomised to 2 treatment groups using simple random sampling method utilizing computer based randomisation. Screw PFN and helical PFN were used for internal fixation with 30 patients in each group. Results: Both groups were similar in respect of age, gender, fracture classification, quality of fracture reduction, duration of hospitalization, post-operative complications, residual/late deformity as well as functional assessment. However, mean duration of surgery was significantly lower (23.1%) in helical PFN group as compared to screw PFN group (43.32 ± 8.20 min vs. 35.20 ± 6.03 min, p < 0.001). Furthermore, mean blood loss was not significant in either of the study groups but it was significantly lesser (30.1%) in helical PFN group as compared to screw PFN group (77.80 ± 17.39 ml vs. 59.80 ± 14.96 ml, p < 0.001). Also, mean number of images taken was significantly lower (58.7%) in helical PFN group as compared to screw PFN group (29.52 ± 4.85 no vs. 18.60 ± 3.12 no, t ¼ 9.47; p < 0.001). Conclusion: Both screw PFN and helical PFN are equally effective implants in internal fixation of unstable trochanteric fractures with no statistically significant difference (p > 0.05) in any of the outcome measures. However, helical PFN group fared marginally better in terms of operative time, blood loss and imaging required.