BackgroundKnee osteoarthritis (KOA) considered as one of the most common degenerative diseases of synovial joint. KOA is mostly managed by physical therapy, focused on pain management, the range of motion and muscle strengthening but muscle flexibility is usually neglected. A study was conducted to evaluate the effectiveness of dynamic soft tissue mobilization (DSTM) in comparison with the proprioceptive neuromuscular facilitation (PNF) stretching in the management of hamstring tightness, reduction of pain intensity and improvement of physical functionality in KOA.MethodsForty eight patients with KOA were randomly allocated to group A receiving DTSM and group B receiving PNF stretching. The cryotherapy and isometric strengthening exercises were also given to both groups. Total treatment duration consisted of 4 weeks, 3 sessions per week and total 12 sessions per patient. Each treatment session comprised of 30 min. At baseline and post treatment, Active knee extension test(AKET), Visual analogue scale (VAS), and Knee Injury and Osteoarthritis Outcome Score (KOOS) were used to assess hamstring flexibility, pain intensity level and physical functional capability respectively. The continuous variables were shown as mean and standard deviations. For the comparison of outcome within and between groups, paired sample and independent t-test was applied. Considerable p value was less than 0.05.ResultsThe between group analysis of VAS, right AKE test, and left AKE test showed non-significant (p > 0.05) mean difference as 0.2 (95% CI= -0.29, 0.70), 1.79 (95% CI= -1.84, 4.59), 1.78 (95% CI= -1.6, 5.19) respectively. KOOS domains of symptom, pain, ADLs, sports and recreational, and quality of life had also non-significant (p > 0.05) mean difference as 1.12 (95% CI= -4.05, 6.3), -5.12 (95% CI= -12.71, 2.46), -2.55 (95% CI= -7.47, 2.38), -2.7 (95% CI= -9.72, 4.3), and − 0.68 (95% CI= -7.69, 6.36) respectively. Significant (p < 0.001) improvement was shown in both groups for all outcome measures after 12 sessions.ConclusionDSTM and PNF stretching, both treatments are equally beneficial in KOA for hamstring flexibility, pain reduction and functional mobility in terms of AKET, VAS, and KOOS respectively.Trial RegistrationClincalTrials.Gov with ID: NCT04925895, 14/06/2021, retrospectively registered.