Mobilization Effect on Hamstring Length

Knee Osteoarthritis is a type of joint disease or common rheumatologic disease that result from breakdown of joint cartilage and underlying bone which is characterized by pain, stiffness, and decreased range of motion. Knee OA is more important not only for its high prevalence rate compared with other types of OA but also for its presentation at earlier age groups particularly in younger age groups of obese women. Symptoms of knee OA progress slowly over years. The incidence of knee OA increases by age and further increase with longer lifetime and higher average weight of the population.

Symptoms of knee OA progress slowly over years. Pain and other symptoms of OA may have a profound effect on quality of life affecting both physical function and psychological parameters. Knee OA is not a localized disease of cartilage alone but is considered as a chronic disease of the whole joint, including articular cartilage, meniscus, ligament, and peri-articular muscle that may result from multiple pathophysiological mechanisms. It is painful and disabling disease that affects millions of patients.

Common symptoms are progressive knee stiffness, pain, difficulties in performing activities such as walking, stair climbing, squatting. Reduction in functional capacity associated with muscular imbalance of lower extremity with pain. Muscles act as brace for knee joint, quadriceps muscle weakness and hamstring inhibition effect this bracing. Muscle dysfunction may actually precede and accelerate the cartilage deterioration. Evidence showed muscle dysfunction is involved in pathogenesis of knee OA. Osteoarthritis (OA) is the most prevalent joint disease and a leading source of chronic pain and disability in the United States. Knee OA accounts for more than 80% of the disease's total burden and affects at least 19% of American adults aged 45 years and older.

Clinical strategies exist for treatment of knee osteoarthritis with aim to reduce symptoms like pain, delay disease progression i.e. pharmacological, physiotherapy and surgical strategies. Patients experience chronic pain that cause reduction in ability to use their joint. Due to prolong inactivity of joint to move through complete range cause muscle shortness along with capsule tightness that leads for further increasing pain and disability. Physical therapy interventions are first line of choice for the treatment of knee OA. Treatment varieties i.e. modalities, therapeutic exercises, manual therapy along with neuromuscular training to improve mechanical environment of knee joint

It is indicated at least 15-30 degree loss of active knee extension with 90 degree of hip flexion account as hamstring shortening. Hamstring muscle tightness and poor flexibility is associated with knee OA. Hamstring flexibility is higher in healthy individual as compared to subjects with knee OA.A statistically significant relationship was found between hamstring tightness and proximal tibiofibular joint grade of arthritis (χ2 test, p=0.004) Recent study reported 97.6% of middle aged men with hamstring muscle tightness Hamstring flexibility is greater in females than males. Research showed that ischio-tibial flexibility reduce pain stiffness and significant functional limitation in knee OA. Joint mobilizations are most widely used in treatment of knee OA having various neuro-physiological effects including decrease in pain, stiffness, activation and inhibition of muscles.The muscular system reflects sensorimotor system it receives information from musculoskeletal and central nervous systems. Changes occur in tone within the muscle are the first responses to nociception by the sensorimotor system. Many studies reported effect of joint pathology on muscle tone for example the presence of knee effusion causes reflex inhibition of the vastus-medialis and multifidus has been shown to atrophy in patients with chronic low back pain. In this study we aim to increase hamstring muscle length through activation of mechanoreceptors by mobilizations.

There is no study conducted yet to determine effect of joint mobilization on adjacent muscle length other than soft tissue techniques which are mainly stretches.

Literature review: randomized control trail (2019) conducted for comparing effectiveness on Proprioceptive Neuromuscular Facilitation(PNF) stretching verses static stretching on hamstring flexibility in knee OA patients showed PNF stretching was better in outcome measures

A study compared static verses intermittent stretching for increase of hamstring muscle length concluded that intermittent stretching is more effective for hamstring flexibility.

A pre-post study (2019) find out effect of unilateral posteroanterior mobilization(UPA) on lumbar spine observed in his study that UPA lumbar mobilizations increased lumbar Range of Motion and hamstring extensibility by a moderate magnitude and this effect remained for 10-15 minutes post treatment.

Study reported Joint manipulations reduce nociceptor stimulus, depress responsiveness of alpha motor neurons causing changes in muscle tone.

Study on active stretching and passive mobilization of cervical spine for neck pain concluded there was increase range of motion in both groups.

comparing Muscle Energy Technique(MET) with conventional treatment for hamstring flexibility in knee OA patients reported that MET was better than conventional treatment.

A randomized control trail(2014)compared immediate effects of neurodynamics slider technique verses static stretch concluded neurodynamics slider technique is more effective for improving hamstring flexibility.

Therapeutic effect of joint mobilization that joint mobilization may promote muscles relaxation thereby increasing joint range of motion

Joint mobilization and traction allows for selective stretching of selected tissue and can be expected to change both elastic and plastic component of stiffness. The intermittent compression and distraction of joint distribute fluid into soft tissue decreasing spasm allowing for easier movement and increase range of motion.

Joint mobilization cause stimulation of Golgi tendon organ activity, and reflex inhibition of the muscle at the end of the passive joint mobilization.

A study concluded that joint mobilization decreases muscle activity, reducing muscle concentric activation, pain, and muscle tension in periarticular-tissue