Lateral Pivot shift test

• It is also known as the test of the maclntosh .

• This test is dynamic but passive test of the knee stability .
• It is to carried out by the examiner without the any activity of to patient.
• It id show the dys-regulation between the rolling & gliding into the knee joint.
• Patient Position is supine.
• In this test movement is do the combination with axial load & valgus force which is apply by to examiner, during of this time knee is do flex from to in extended position.
• When the test is positive, it is indicates injury of the ACL [ anterior cruciate ligament] .

What is Purpose of this test?

• This test is used to detect the anterolateral rotary instability of the knee.
• It is a primary test for the assess of the ALRI .
• It is an excellent test for rupture Means third – degree of sprain of the ACL [ anterior cruciate ligament].

Technique of pivot shift test :

• Patient position for test is supine.
• In this position legs are relaxed.
• Then examiner is grasps heel of to involved leg & opposite hand is place to laterally means externally on to proximal tibia like as to just distal of to knee.
• The examiner is apply to valgus stress & axial load while to do internally rotate means medial rotate of the tibia & knee is move into the flexion from of fully extended position.

Result of pivot shift test :

• During this test ,the tibia moves away form the femur on the lateral side but rotates medially & moves to anteriorly in relation to the femur.
• Positive test is indicated to sub-luxation of to tibia while to femur is do to externally rotates means laterally rotates followed by to reduction of to tibia at 30-40 degrees of flexion.

What is the research of pivot shift test?

• This test is attempts to reproduce rotary & translator instability in the anterior cruciate ligament [ ACL ] deficient of knee.
• This test is clinically relevant & reproduces of functional movement of to knee joint.
• This test is reliable for in both condition ; self-assessment of laxity of patient & with the surgical performance.
• Sensitivity of test = from 0.18 to 0.48
• Specificity of test = from 0.97 to 0.99

Grading of pivot shift test :

• This grade is according to the rotation.

Grade I pivot shift test :

• When to tibia is held in maximal medial means internal rotation, it is a abnormal movement which is feel in small & gentle sliding of reduction.
• It is occur into neutral / lateral rotation.
• It is palpable when the patient is awake but it is more obvious for to under general anesthesia.
• Grade I of knee is to result of the residual laxity / partial cruciate injury.

Grade II pivot shift test :

• It is a define by to clunk when to tibia is in to medially means internal rotated position.
• There is to abnormal movement in to neutral position.
• Test is negative when to tibia is held into position of the definite lateral means external rotation.
• Because of to clunk & do the abnormal movement into neutral position.
• It is a difference between to grade I & grade II.
• Into grade II knee is do the more obvious to anterior instability, due to non- functioning of ACL.
• Grade of to pivot shift test is seen after to fresh the isolated rupture of to anterior cruciate restraints & also into chronic instability of to moderate degree.

Grade III pivot shift test :

• When the tibia is held in to neutral/moderate lateral means external rotation & abnormal movement is do with the pronounced clunk is to takes place.
• Tibia is follow path of maximal anterior laxity.
• Due to the gravity, femur is falls onto posteriorly.
• Tibia is located in the anteriorly translate position with the lateral means external rotation.
• With medial means, internal rotation to shift is less obvious.
• With acute injury knee is moderate to severe damage to posteromedial & posterolateral structures, including complete anterior cruciate ligament injury, we find a grade III pivot shift.
• It is also to case when to knee is in severe chronic instability & consequent stretching of the secondary posterior restraints.

• Table 1 :
• It shows displacement of to medial & lateral plateau of to knee.
• Comparing different grades of to severity of injured knee in accordance with to pivot shift test.

Pivot shift test	Normal of knee	Grade I	Grade II	Grade III
Medial plateau	3mm	5mm	10mm	15mm
Lateral plateau	5mm	12mm	18mm	22mm

Remark of this table = lateral side of to tibia plateau is always more mobile.

Which is the structure is affected during this positive test?

1. Anterior cruciate ligament
2. Posterolateral capsule
3. Arcute – popliteus complex
4. Lateral collateral ligament
5. Iliotibial band

Clinical Bottom Line of pivot shift test :

• Meaning of this test is in determine to clinical significance .
• Which is do the different grades of test for to define the level & direction of laxity, which is called to anteromedial or posterolateral & anterolateral .
• It is results into visualization of to progression in to chronic anterior cruciate injury.
• It is due to successive use of three positions of tibial rotation .

Other part of pivot test

• If the patient is tense or apprehensive , the test is modified which is called to soft pivot shift test.

• The patient lies supine & examiner supports the test foot with one hand while placing the other hand over the calf muscle 10 to 20 cm means 4 to 8 inches distal to the knee joint .
• Examiner is flexes & extends the knee slowly & gently to relax the patient.
• After do the three to five cycles, the examiner apply axial compression while the other hand over the calf exerts anterior pressure.

Result of this test

• Positive test is indicate to tibia sublaxates & reduces but not with the same apprehensive.