This randomized controlled trial will be conducted at Riphah Rehabilitation Clinic and Spinacure clinic in Lahore over a 9-month period. A sample size of 42 participants, aged 18 to 45, will be selected using convenient sampling. Informed consent will be obtained from all participants. Participants will be divided into two groups: Group A will receive Post-Isometric Relaxation in addition to standard physical therapy, while Group B will receive Post-Facilitation Stretch in addition to standard physical therapy. Outcome measures, including the Numeric Pain Rating Scale (NPRS) for pain, inclinometer for mobility assessment, and Oswestry Disability Index (ODI) Urdu version for disability, will be assessed at baseline and after 4 weeks. Inclusion criteria include patients with CLBP aged 18-45 years, with pain levels between >3 and <7 on the NPRS, and an ODI score between 14% and 50%. Exclusion criteria include any neurological symptoms, systemic soft tissue and bony disease, and previous spinal surgeries. Data will be analyzed using IBM SPSS 25.0.

Low back pain (LBP) is one of the primary causes of physical impairment globally, affecting a significant portion of the population. It is associated with a high rate of absenteeism from work and substantial healthcare costs due to its pervasive nature. Chronic low back pain (CLBP), specifically, is a condition where pain is localized in the lumbar region and persists for more than 12 weeks. In contrast to acute low back pain, which typically resolves within six weeks, CLBP is characterized by a complex interplay of physical, psychological, and social factors that contribute to its persistence and chronicity .

Compared to other diseases, it is the primary cause of medical consultations, affects quality of life and performance at work, and occurs in a proportion that is similar in all cultures and ethnicities. Over 20% of people globally suffer from chronic LBP, and 24-80% of individuals experience a relapse during the first year. The prevalence of chronic low back pain (CLBP) in Pakistan is a significant health concern. A national survey conducted in 2021 found that 18% of individuals experiencing chronic pain reported low back pain as their primary complaint. This survey, involving 4,801 participants, highlighted the substantial impact of CLBP on daily life and the need for better pain management and awareness among patients (Journal of the Medical Association).

Management of CLBP typically involves a combination of pharmacological and non-pharmacological treatments. Pharmacological interventions include nonsteroidal anti-inflammatory drugs (NSAIDs), muscle relaxants, and analgesics to manage pain and inflammation. In some cases, antidepressants and anticonvulsants are prescribed for their pain-modulating effects. Non-pharmacological approaches are crucial for improving mobility and function. Physical therapy, including exercise programs designed to strengthen core muscles and improve flexibility, plays a vital role in rehabilitation. Manual therapy techniques, such as spinal manipulation and massage, and cognitive-behavioral therapy (CBT) to address the psychological aspects of chronic pain are also important. Lifestyle modifications, such as weight management, ergonomic adjustments, and activity modifications, are essential components of a comprehensive treatment plan.

Chronic low back pain (CLBP) is a prevalent and serious problem that affects millions of people, disrupting their daily activities and quality of life. To manage this condition effectively, strategies that reduce pain, improve movement, and lessen disability are needed. Post Isometric Relaxation (PIR) and Post Facilitation Stretch (PFS) are two techniques that can help with these goals. This study aims to compare the effects of PIR and PFS on pain, mobility, and disability in patients with CLBP. By finding out which method is more effective, clinicians can choose better treatments, improve patient outcomes, create better treatment guidelines, and enhance the quality of life for those suffering from chronic low back pain. This approach can also help lower healthcare costs by reducing the need for more invasive treatments and long-term medication use.

Inclusion Criteria:

• Age of patient between 18 to 45 year
• Both gender
• (LBP) for more than 3 months
• Diagnosis of Chronic Low Back Pain (CLBP)
• Negative SLR, negative faber test, negative lumber quadrant
• Lumber extension test positive, positive scobber test
• Having low back pain below the costal margin and above inferior gluteal folds and suffering from low back pain
• Disability level of more than 14% and less than 50% according to Oswestry questionnaire
• NPRS score of >3 to ≤7

Exclusion Criteria:

• Chronic systemic soft tissue and bony disease
• Any neurological symptoms involving Prolapsed Intervertebral Disc, Radiculopathy Back pain with trauma
• History of recent abdominal, back surgeries and pregnancy