Bent – knee stretch test :

• This test is also known as the BK stretch test.
• This test is applied by a doctor or therapist to check the tightness of proximal hamstrings.
• This test is applied in examine part of the assessment.

Purpose of bent – knee stretch test :

• Demonstration of the Bent Knee Stretch Test
• This test is used to Evaluates Hamstrings as to the cause of hip or thigh pain.

The technique of this test :

• The patient lies supine with the AISI level.
• The examiner is try to balance the pelvis of both legs.
• The balancing implies a line that is joining the ASIS perpendicular to the two lines formed by straight legs.
• If a contracture is present, the affected leg forms an angle of less than 90′ with the line joining the two ASISs.
• When the examiner tries attempts to balance the lower limb with the pelvis, the pelvis is shifted down on the unaffected.
• Side / the unaffected side & so balancing is not possible.

Result of this test :

• Normally, hip abduction should be 30′ to 50′ before the ASIS moves.
• If the ASIS means anterior superior iliac spine moves before this degree means before 30′ to 50′ degree, it indicates the tightness of adductors muscle & also feels the muscle stretch in end feel.
• This type of contracture leads to functional shorting of the limb rather than of true shorting.

Pathology of the bent-knee stretch test :

• Proximal Hamstring Tendinopathy
• Hamstring Strain

Evidence of the bent-knee stretch test :

• Sensitivity of this bent-knee stretch test : 0.84
• Specificity of this bent-knee stretch test: 0.87
• PPV of this bent-knee stretch test: 0.86
• NPV of this bent-knee stretch test: 0.85
• LR+ of this bent-knee stretch test: 6.5
• LR- of this bent-knee stretch test: 0.18

Modification of bent-knee stretch test :

• For the Modification, the patient is lying supine, with the hip & knee are into extension.
• The therapist takes the heel into one hand & holds the knee with the other hand.
• The therapist brings the hip & knee in maximal flexion & then rapidly straightens the knee.
• This modification of tests is used to identify a hamstrings origin tendinopathy, but do not replace with an MRI