Examination of the knee joint

INTRODUCTION

It is important to have a systemic plan for the examination of knee arrive at the correct diagnosis, to identify its impact on the patient, to understand the patients’ needs and concerns and then to formulate a treatment plan that is individualized for the particular patient. A thorough knowledge of the normal anatomy, biomechanics of knee and the pathology of various knee disorders is a must for proper examination of knee and for the interpretation of physical findings.
First listen to the patient carefully to understand his concerns and needs and also to gain his confidence.
The involved and the normal knee should be adequately exposed to examine the knee. Always examine the spine and the hip to rule out conditions that lead to referred pain in the knee and any associated hip and spine disorders.
Always compare with the uninvolved side as wide range of anatomic and functional variations exist.
Examination should be gentle and as painless as possible to avoid worsening of injury and to ensure a cooperative patient.
The function of the knee is assessed by the patient’s ability to weight bear, walk, ability to squat, sit cross-legged, run, stair climb and the level of restriction of activities of daily living and the occupational and recreational activities.

HISTORY

Presenting complaints – Give the presenting complaints in the chronological order.

History of presenting complaints

Pain

Duration – How long the pain is present?

Onset – How it started? Symptoms may begin after a traumatic event, after unaccustomed activity. It may start suddenly or gradually. Acute onset of symptoms is seen with trauma, infections and crystal deposition disorders.

Progress – What has happened to the pain after it started? Has it increased, decreased or remain in the same intensity. Is it constant or intermittent? What is its present status?

Site- Ask the patient to pinpoint the site of pain with a single finger. Note down whether in the joint line medially or laterally, around the patella or popliteal fossa. Don’t use vague terms like pain in the hip. Remember that a patient with hip disease may present with knee pain.

Severity- How disabling is the pain? What is its effect on routine activities, self-care, locomotion, occupation and recreational activities?

Character – What is the nature of pain? Throbbing pain is due to inflammatory causes, burning pain is due to neuropathic causes.

Radiation- Pain of hip may radiate to knee or thigh. Pain radiating below knee is due to sciatica.

Aggravating and relieving factors- Mechanical pain due to osteoarthritis or impingement is aggravated by activity and relieved by rest. Pain due to inflammatory arthritis is aggravated by rest and partially relieved by activity.

Diurnal variation- Pain of osteoarthritis is more towards the evening and less when patient gets up in the morning. Pain of inflammatory arthritis is more in the morning and less in the evening. Nocturnal pain that interferes with sleep is an ominous sign of malignancy or infection.

What other symptoms are associated with pain?

Deformity

How long the deformity is present?
How did it start?
How is it progressing?
Any associated symptoms such as giving way, locking, popping, catching, grinding?

Is there any history of trauma or infection?
Is there any history of patellar instability?

Limb length discrepancy

How long it is present?
Is it static or progressive?
Associated symptoms?
Any history of infection or trauma?

History to assess function

Walking ability
Normal or altered
Restricted or unrestricted
Aided or unaided
If aided; which aid is used
Ability to stand, squat and kneel
Ability to sit cross legged
Ability to jog, sprint, go up or down the hill, go up or down the stairs
Pivoting and cutting ability
Ability to stand, squat and kneel

Fever

Whether associated with chills and rigor, severity, continued or intermittent and the treatment taken.

History of trauma

What was the mechanism of injury?
Direct trauma
Whether the foot was grounded or not?
Any twisting or hyperextension of knee?
What were the symptoms immediately after trauma?
Was the patient’s knee deformed?
Was there a loud pop?
Was he able to walk or use the limb?
Was there knee swelling? If yes when it appeared? Effusion of meniscus injury develops late.
What was the emergency treatment given?
How long the patient was immobilised or advised rest at that time?
Did the joint return to pre-injury status after initial treatment?
What are the present symptoms? Instability? Locking? Abnormal sounds? Pain? Deformity?
What brings the patient now? What does he want?

Past history

History of similar episodes in the past
Past injuries and their treatment
Hypertension
Diabetes mellitus
Inflammatory arthropathy
Septic arthritis
Tuberculosis
Umbilical sepsis
H/o prolonged IV infusion in childhood
Blood Dyscriasis
Frequent episodes of bleeding
Frequent episodes of infection
H/o Childhood limping
Previous hospital admission
Previous surgery
Previous trauma

Personal history

Prolonged drug intake
Alcohol abuse
Smoking
Diet
Menstrual history
Occupational history
Recreational activities
Treatment History
Family history
Any family history of dwarfism
Any family history of angular deformities
Metabolic disorders
Similar illness
Tuberculosis

GENERAL EXAMINATION

Head to foot examination
Eyes- Blue sclera, iritis ,uveitis, squint, microophtalmos, cornea, pigmentation of sclera.
Pinna- Low set, blackish discoloration.
Cheeks- Malar rash.
Mouth – Normal dental hygiene, arch of palate.
Hair Line- Normal or low
Neck – Webbing , thyroid swelling.
Nipples- Normal level or not.
Shape of chest wall- Pectus carinatum/ excavatum.
Abdomen- Protuberant , undescended testis , hernias.
Nails- Pitting.
Palms and soles- Hyperkeratosis.
Thickening of lower end radius, malleoli and costochondral junctions.
Ligamentous laxity (Wynne-Davis Criteria- 3 out of 5 needed for diagnosing generalized laxity)
Apposition of thumb to flexor aspect of forearm
Passive extension of fingers so that they lie parallel to the forearm.
Hyperextension of elbow at least 10 degrees
Hyperextension of knee at least 10 degrees
Excessive passive dorsiflexion of ankle (45 degree) with eversion of foot.
Neurocutaneous markers

INSPECTION

Watch how the patient walks into the examination room. Is the gait normal? Is it painful? Is the any deformity or shortening? Is there any intoeing?

Make the patient stand with his feet and knee together. Look for any varus or valgus deformity by observing the patient from the front. Observe from the side to identify any flexion deformity or hyperextension deformity. Look at the popliteal fossa from behind. Observe muscle bulk and symmetry especially of quadriceps.

Make the patient sit on a chair with the knee bend to 90 degrees. Observe the position of patella. In the normal the anterior surface of patella will be at an angle of 45 degrees to the floor and it will be placed centrally within the femoral trochlea. In patella alta, it will be more horizontal and in patella infera it will be more vertical.

Make the patient lie supine on a couch. Look suprapatellar and parapatellar fullness. Observe the position of tibial tuberosity.

Look at the shape of the bones of the knee and the soft tissues to detect any swelling or muscle wasting.

Observe the medial and lateral surfaces of the knee from either side.

Make the patient prone and observe the back of thigh, popliteal fossa and the calf.

PALPATION

First feel for elevated temperature with the dorsum of examiners fingers at the joint line, patella, suprapatellar pouch, femoral and tibial condyles, popliteal fossa and the calf. Many a times it helps to pinpoint the area of pathology.

When palpating anatomic structures, feel for tenderness, break in continuity, swelling, thickening and their position in relation to normal location.

First flex the knee to 90 degrees to locate the joint line. Palpate the joint line on the medial and lateral side, palpate the medial and lateral femoral condyles, then palpate the tibial condyles and the tibial tuberosity. From the tibial tuberosity palpate up the patellar tendon to the inferior pole of patella. Extend the knee, displace the patella laterally and medially and then insinuate the examiner’s fingers to feel the undersurface of patella.

Palpate the superior border of patella and then roll the fingers superolaterally and superomedially to detect synovial thickening. Palpate the suprapatellar pouch for any synovial thickening and loose bodies. Milk the suprapatellar pouch down to evacuate the fluid to the area beneath the patella and do the Patellar tap test
Palpate down towards the tibia. Palpate the fibular head and the common peroneal nerve winding around it. Place the knee into the figure 4 position and feel the cord like fibular collateral ligament from the fibular head to the lateral epicondyle.

Make the patient prone, palpate the back of thigh, popliteal fossa and the calf. Palpate the hamstrings and feel for the popliteal pulse.

MOVEMENTS

Movements of the knee occur in the sagittal plane. Normal range of movements of the knee is from 5-10 degrees of hyperextension to 135 degree flexion. Movements should be assessed actively and passively and should be measured with a goniometer. During passive movements the amount of joint play and the quality of end point should be assessed. The end point may be of six types; tissue approximation, capsular feel spasm, springy block, empty feel or bone to bone.

If movement is painful then the relationship between appearance of pain and the resistance to movement should be noted. In acute conditions, the pain appears before resistance to movement. Appearance of pain and resistance to movement appear together in subacute conditions. Resistance to movement occurs before appearance of pain in chronic conditions.

MEASUREMENTS

Q Angle

It is the angle between the axis of pull of the quadriceps and the axis of the patellar tendon. Normally is 10-200. It should be measured in full extension, 300 flexion and in the sitting position with knee flexed to 900 (tubercle-sulcus angle). Mark the centres of patella, tibial tuberosity and the anterior superior iliac spine (ASIS). Draw a line from the centre of ASIS through the centre of patella and beyond. Draw another line from the centre of tibial tuberosity to the centre of patella and beyond. Measure the angle between the lines.

Circumference

Measure the circumference at the following levels.

1- At the joint line
2- 5 cm above the joint line to assess effusion or vastus medialis obliquus wasting
3- 15 cm above the joint line to assess quadriceps bulk
4- 15 cm below the joint line to assess the calf muscle bulk

SPECIAL TESTS

Special tests are done to detect specific disorders or to detect injury to specific anatomic structures. Four sets of tests are usually done; one set each for evaluation of knee joint effusion, patellofemoral disorders, meniscus or articular cartilage lesions and ligamentous instability.

Special tests to detect knee effusion

Patellar tap test
Patient position- Supine.
Joint position- Knee maximally extended. Quadriceps relaxed.
Procedure- Milk the suprapatellar pouch to displace the fluid collected there into the retropatellar area. Sharply tap the patella posteriorly towards the femoral trochlea.
Interpretation- If there is moderate effusion the patella will be floating with no contact with the femur. When tapped it will move posteriorly till it contacts the femur and bounce back. It needs about 50 ml of fluid within the joint to make the patellar tap test positive.

Fluctuation test

Patient position- Supine.
Joint position- Knee maximally extended. Quadriceps relaxed.
Procedure- Milk the suprapatellar fossa to displace maximal amount of fluid into the rest of the joint cavity. Place index finger and thumb of one hand on either side of patella superiorly. Place the index finger and thumb of other hand on either side of patella inferiorly. Alternatively press the fingers of either hand to elicit fluctuation.
Interpretation- In presence of effusion, fluctuation can be elicited between the fingers.

Stroke test

Patient position- Standing.
Joint position- Knee fully extended. Quadriceps relaxed.
Procedure- Gently stroke the lateral aspect of knee from the superolateral aspect of patella to the lateral joint line. Observe the medial side for a wave like displacement of fluid. Repeat the same on the medial side.
Interpretation- Will be positive in presence of effusion. Efffusion is graded as follows.
Zero – No wave produced on downstroke
Trace – Small wave on medial side with downstroke
1+ – Larger bulge on medial side with dowstroke
2+ – Effusion spontaneously returns to medial side after upstroke (no downstroke necessary)
3+ – So much fluid that it is not possible to move the effusion out of the medial aspect of the knee

Special tests for patellofemoral disorders

Fairbank Apprehension Test

Patient position- Supine on the examination couch.
Joint position- Knee extended. Quadriceps relaxed.
Procedure- Hold the patella by placing the examiner’s fingers on the medial and lateral border of the patella. Try to displace the patella. Note the response of the patient.
Interpretation- Discomfort or apprehension during the test indicates patellar instability.

Patellar glide test

Patient position- Supine on the examination couch
Joint position- Knee flexed to 300. Quadriceps relaxed.
Procedure- Hold the patella by placing the examiner’s fingers on the medial and lateral border of the patella. Try to displace the patella medially and laterally. Note the amount of displacement possible as the percentage patellar width or in millimetres.
Interpretation- If medial glide is less than 25% or <5mm, then there is tightness of lateral patellar retinaculum. If medial or lateral glide is more than 75%, then there is laxity of parapatellar retinaculum. Discomfort or apprehension during the test indicates patellar instability.

Patellar tilt test

Patient position- Supine on the examination couch

Joint position- Knee kept in extension. Quadriceps relaxed.

Procedure- Hold the patella by placing the examiner’s fingers on the medial and lateral border of the patella. Try to lift the medial border of patella off the femur while depressing the lateral border and vice versa. Note the amount of tilt possible.

Interpretation- Normally lateral border can be tilted slightly beyond the horizontal. If lateral border can be tilted less than normal then there is tightness of lateral patellar retinaculum. If the medial border can be tilted more if there is laxity of medial patella retinaculum.

Clarke’s patellar grind test

Patient position- Supine on the examination couch

Joint position- Knee extended. Quadriceps relaxed.

Procedure- Examiner places his hand on the patella and compresses the patella against the femur. Ask the patient to contract his quadriceps muscle actively.

Interpretation- Pain indicates disease of the articular cartilage of patella.

McConnell’s test

Patient position- Seated on the couch with legs hanging down the edge of the table.

Joint position- Knee bend to 90 degrees.

Procedure- Ask the patient to externally rotate the limb while performing resisted isometric contractions of the quadriceps at 0, 30, 600, 90 and 120 degrees. During these resisted isometric quadriceps contractions, apply a medially directed pressure and laterally directed pressure on the patella.

Interpretation- Pain or discomfort during isometric contractions when applying laterally directed pressure indicates symptoms due to patellar maltracking.

Patellar tracking

Patient position- Seated with knee flexed and limb hanging freely

Procedure- Ask the patient to move the knee joint actively through the entire arc of flexion-extension several times. Observe the movement of patella.

Interpretation- Normally the patella progressively become engaged in the trochlea with increasing degrees of knee flexion. Patella is pulled axially by the rectus femoris and the vastus intermedius and obliquely by the vastus lateralis and the vastus medialis. Static stabilization is provided by the medial and lateral parapatellar retinaculum. The shape of trochlea and the position of patella and the location of tibial tuberosity also influence patellar tracking. J sign is seen if the patella was laterally subluxed in full extension and suddenly moves medially and engages the trochlea during flexion.

Special tests for meniscus pathology

McMurray’s test

Patient position- Supine on the examination couch.

Joint position- Knee flexed fully. Quadriceps relaxed. Procedure- Hold the foot the patient with one hand. With the other hand, stabilize the knee and keep one finger on the joint line. To test for medial meniscus, apply a valgus and external rotation stress on the knee. Gradually extend the knee fully. To test lateral meniscus, apply a varus and internal rotation stress.

Interpretation- If clicks or thud from the joint, or if the patient complains of pain then the test is positive for the meniscus injury.

Bragard’s test

Patient position- Supine on the examination couch

Joint position- Knee flexed to 90 degrees.

Procedure- Palpate the medial joint line for tenderness in neutral rotation. Extend the knee and externally rotate the knee and palpate for medial joint line tenderness. Interpretation- If there is no tenderness in flexion and neutral rotation and if there is tenderness in the medial joint line on extension and external rotation, the test is positive for the medial meniscus injury. Reason is that the medial meniscus becomes more anterior in extension and external rotation.

Steinman’s first test

Patient position- Supine

Joint position- Hip flexed. Knee flexed to 90.

Procedure- Rotate the tibia externally and internally. Interpretation- Pain on external rotation indicate medial meniscus injury and pain on external rotation indicate lateral meniscus injury.

Bounce home test

Patient position- Supine.

Joint position- Knee fully flexed.

Procedure- Keep the heel of the patient’s foot in the palm and allow the knee to extend.

Interpretation- Normally the knee will extend fully. Limitation of full extension with a rubbery end feel is suggestive of a locked knee due to bucket handle tear of meniscus.

Steinman’s second test

Patient position- Supine on the examination couch.

Joint position- Knee flexed fully.

Procedure- Palpate the joint line for tenderness with the knee in flexion and in extension.

Interpretation- If the area of tenderness moves posteriorly with knee flexion and anteriorly with knee extension then the test is positive for the meniscus Injury.

Apley’s grinding test

Patient position- Prone

Joint position- Knee flexed to 90 degrees.

Procedure- Fix the limb by placing the knee of the examiner on the patient’s thigh. Hold the foot of the patient. Distract the knee and rotate internally and externally. Give axial compression and rotate internally and externally. Note any restriction or excessive rotation and pain during these manoeuvres.

Interpretation- More pain during compression indicate meniscus injury and more pain during distraction indicate ligamentous injury.

Bohler’s test

Patient position- Supine on the examination couch.

Joint position- Knee extended.

Procedure- Apply valgus stress and varus stress.

Interpretation- Pain felt at the medial joint line on varus stress indicate medial meniscus injury and pain felt at the lateral joint line on valgus stress indicate lateral meniscus injury.

Thessaly test

Patient position- Standing on the affected limb. Other limb is off the ground. The examiner supports the patient by holding the extended hands.

Joint position- Knee flexed to 5 degrees and then to 20 degrees.

Procedure- Ask the patient to twist the body to the left and the right side to rotate the weight bearing knee internally and externally.

Interpretation- Pain felt at the joint line indicate meniscus or chondral lesion.

Reliability of Thessaly test- Sensitivity of 90.3%, specificity of 97.7%, positive predictive value of 98.5%, negative predictive value of 86.0%, likelihood ratio for a positive test of 39.3, likelihood ratio for a negative test of 0.09, and diagnostic accuracy of 88.8%.

Harrison BK, Abell BE, Gibson TW- The Thessaly test for detection of meniscal tears: validation of a new physical examination technique for primary care medicine. Clin J Sport Med.  2009 Jan;19(1):9-12. doi: 10.1097/JSM.0b013e31818f1689.

Squat test (Ege’s test)

Patient position- Standing on both lower limbs.

Joint position- Hip and knee extended.

Procedure- Ask the patient to squat first with the foot turned in internal rotation and then in external rotation.

Interpretation- Pain on squatting with the foot externally rotated indicate medial meniscus lesion and pain with foot in internal rotation indicate lateral meniscus lesion.

Duck walking test (Chidress test)

Patient position-Sitting in the deep squatting position.

Joint position- Hip and knee in maximum flexion.

Procedure- Ask the patient to duck walk in deep knee flexion.

Interpretation- Pain felt at the joint line suggestive of meniscus lesion.

Merke’s test

Patient position- Standing on the affected lower limb with the other limb off the ground.

Joint position- Knee in extension.

Procedure- Ask the patient to slightly bend the knee and then rotate the body to the left and right.

Interpretation- Pain felt at the joint line indicate meniscus pathology.

Peyr’s test

Patient position- Sitting in the cross legged sitting position (Turkish or Indian sitting position)

Joint position- Hip in flexion and external rotation. Knee fully flexed.

Procedure- Ask the patient to sit in the Turkish sitting position.

Interpretation- Pain on the medial aspect of knee indicate medial meniscus lesion.

Helfet’s test

Patient position- Seated on the couch with limb hanging over the edge of the couch.

Joint position- Knee flexed to 90 degrees.

Procedure- Ask the patient to extend the knee. Note the position of tibial tuberosity in relation to the midline of the patella.

Interpretation- During extension, the tibia externally rotates during the final degrees of knee extension as the medial femoral condylar articular surface is longer than the lateral femoral condyle. Hence the tibial tuberosity becomes more laterally placed in full extension. If the normal external rotation is absent it indicates injury to medial meniscus.

Tests for ligamentous instability

Valgus stress test

Purpose- To assess the structural integrity of medial collateral ligament.

Patient position- Supine on the examination couch.

Joint position- Initially the knee is flexed to 30 degrees. Then the knee is kept in 0 degree extension.

Procedure- Hold the leg with one hand at the ankle. With the other hand hold the knee in such a way that thumb is over the medial joint line to detect amount of opening of the joint and the other fingers are on the lateral side to act as the fulcrum for application of valgus stress. Bend the knee to 30 degree and apply valgus stress. Note the amount of widening of the medial joint line. Repeat the test at 0 degree extension. Do the test on the other limb and compare the amount of widening.

Interpretation- If there is widening of the medial joint space in excess to the normal side in 30 degree flexion of knee there is injury to the medial collateral ligament. If there is excessive opening up of medial joint space in 0 extension as well as in 30 degree flexion, then there is injury to the MCL and the cruciate ligaments. The laxity is graded as follows. 0-5mm opening in comparison to opposite side. 5-10mm opening >10mm opening

Varus stress test

Purpose- To assess the structural integrity of fibular collateral ligament.

Patient position- Supine on the examination couch.

Joint position- Initially the knee is flexed to 30flexion. Then the knee is kept in 0 degree extension.

Procedure- Bring the lower limb of the patient beyond the edge of the table. Hold the leg with one hand at the ankle. With the other hand hold the knee in such a way that thumb is over the lateral joint line to detect amount of opening of the joint and the other fingers are on the medial side to act as the fulcrum for application of varus stress. Bend the knee to 30 degree and apply varus stress. Note the amount of widening of the lateral joint line. Repeat the test at 0 degree extension. Do the test on the other limb and compare the amount of widening.

Interpretation- If there is widening of the lateral joint space in excess to the normal side in 30 degree flexion of knee there is injury to the lateral collateral ligament. If there is excessive opening up of lateral joint space in 0 degree extension then there is injury to the LCL and the cruciate ligaments. The laxity is graded as follows.
0-5mm opening in comparison to opposite side.
5-10mm opening
>10mm opening

Cabot manoeuvre

Patient position- Supine.

Joint position- Knee kept in “figure of 4” position.

Procedure- Feel the lateral collateral ligament as a cord like structure between the lateral epicondyle and fibular head.

Interpretation- Inability to feel the lateral collateral ligament as a cord like structure indicate injury.

Lachmann- Tillat test

Patient position- Supine

Joint position- Knee flexed to 15 degree. Slight external rotation of hip helps in relaxing the quadriceps muscle.

Procedure- Stabilize the distal femur with one hand and stabilize the proximal tibia with the other hand. If the patient’s thigh is of large size, then the examiner places his bend knee under the patient’s thigh and one hand over the distal femur to stabilize the knee. Apply anteriorly directed and then posteriorly directed force on the proximal tibia.

Interpretation- Excessive anterior translation of tibia when compared to the opposite side with a soft end point is suggestive of anterior cruciate ligament injury. Excessive posterior translation of tibia when compared to the opposite side with a soft end point is suggestive of posterior cruciate ligament injury.

Validity- Sensitivity ranges from 80-99%. Specificity under anaesthesia is 95%.

Anterior drawer test

Patient position- Supine.

Joint position- Hip flexed to 45° and knee flexed to 90°.

Procedure- Sit on the patient’s foot in neutral rotation to stabilize it. Palpate the hamstring tendons to ensure that they are relaxed. Observe from the side to rule out any posterior sagging of tibia suggestive of posterior cruciate ligament tear. Place the hands behind the proximal tibia and thumbs on either side of patellar tendon with the tip of thumb over the femoral condyles. Apply an anteriorly directed force to the proximal tibia. Should be done in neutral rotation, 30 degree internal rotation and 30 degree external rotation.

Interpretation- Increased anterior displacement of tibia when compared with the opposite side is indicative of an anterior cruciate ligament tear. It may be false negative in patients with bucket handle meniscus tear with locking. External rotation tightens the PCL and the posterolateral corner and if they are intact the test is negative in external rotation.

Validity- Sensitivity increases when performed under anaesthesia. Sensitivity is less in acute injuries. Sensitivity of the test is between 20-40% in acute cases and between 40-70% in chronic cases. Sensitivity of the test is between 60-95% when examined under anaesthesia.

Posterior drawer test

Patient position- Supine.

Joint position- Hip flexed to 45° and knee flexed to 90°.

Procedure- Examiner sits on the subject’s foot in neutral rotation to stabilize it. Palpate the hamstring tendons to ensure that they are relaxed. Place the hands around the proximal tibia and thumbs on the tibial tuberosity. Apply a posteriorly directed force to the proximal tibia.

Interpretation- Increased posterior tibial displacement compared with the opposite side is indicative of posterior cruciate ligament tear.
Validity-

External rotation recurvatum test

Sag test

Patient position- Supine.

Joint position- Hip flexed to 45° and knee flexed to 90°. Stabilise the foot in neutral rotation.

Procedure- Observe the position of tibia in relation to the femoral condyles. Normally the tibial tuberosity lies one centimetre anterior to the femoral condyles resulting in a step-off.

Interpretation- When the posterior cruciate ligament is torn, the tibia is subluxed posteriorly due to the effect of gravity.

Validity-

Godfrey’s test

Patient position- Supine.

Joint position- Hip flexed to 90° and knee flexed to 90°. Stabilise the foot in neutral rotation. Ask the patient to extend the knee.

Procedure- Observe the position of tibia in relation to the femoral condyles. Normally the tibial tuberosity lies one centimetre anterior to the femoral condyles resulting in a step-off.

Interpretation- When the posterior cruciate ligament is torn, the tibia is subluxed posteriorly due to the effect of gravity. The active contraction of quadriceps leads to reduction of gravity induced posterior subluxation of tibial condyles.

Quadriceps active test– Knee flexed to 150 ask the patient to contract the quadriceps keeping the knee in flexion.

Active resisted extension test– Keep the knee in 150 flexion. Ask the patient to extend the knee against resistance.

Patellar reflex reduction test– Keep the knee in 300 flexion. Elicit patellar tendon reflex. Active quadriceps contraction leads to correction of posterior sag.

McIntosh’s Pivot shift test

Patient position- Supine

Joint position- Knee extended.

Procedure- Examiner lifts up the patient’s leg with the knee in extension by holding at the ankle with one hand. Apply an internal rotation force. With the other hand, support the limb with the palm over the posterolateral aspect of knee close to the fibular head. Apply a strong valgus force and flex the knee.

Interpretation- Pivot shift is anterior subluxation of lateral tibial condyle when the knee is extended and the reduction of subluxation when the knee is flexed. Internal rotation exaggerates the subluxation and the valgus force prevents easy reduction of subluxation. When the knee is flexed with valgus force initially the lateral tibial condyle remains subluxed and suddenly gets reduced beyond 30 degree flexion with an demonstrable thud. When the knee is flexed the iliotibial band passes posterior to the centre of rotation of knee exerting a posterior pull reducing the anterior subluxation of lateral tibial condyle.

Noye’s flexion rotation drawer test

Noyes glide pivot shift test

Pivot shift test done with axial compression and without internal rotation.

Hughston’s jerk test

Pivot shift demonstrated from flexion to extension. It demonstrates the subluxation of the lateral tibial condyle anteriorly during extension. It is done with valgus stress and internal rotation while the knee is moved from flexion to extension.

Losee’s test

Slocum’s Anterolateral Rotary Instability (ALRI) Test /Larson’s test

Patient position- Patient lies in the lateral position with the affected limb up. The pelvis is tilted slightly posteriorly. The affected limb rests with only the heel in contact with the examination couch with the knee in extension. This will exert an internal rotation stress on the knee leading to anterior subluxation of lateral condyle of tibia.

Joint position- Knee in extension.

Procedure- Lift up the limb by holding the ankle with one hand to apply a valgus stress on the knee. Keep the other hand on the joint line. Flex the knee.

Interpretation- If there is rotatory instability due to ACL deficiency, the knee can be felt to reduce at about 400 of flexion.

Reverse pivot shift test

Patient position- Supine

Joint position- Knee flexed.

Procedure- Examiner lifts up the patient’s leg with the knee in flexion by holding at the ankle with one hand. Apply an external rotation force. With the other hand, support the limb with the palm over the lateral aspect of knee. Apply a strong valgus force and extend the knee.

Interpretation- Reverse pivot shift is posterior subluxation of lateral tibial condyle when the knee is flexed and the reduction of subluxation when the knee is extended. External rotation exaggerates the subluxation and the valgus force prevents easy reduction of subluxation. When the knee is extended with valgus force, initially the lateral tibial condyle remains subluxed and then suddenly gets reduced with extension with a demonstrable thud.

Tests for posterolateral corner injuries

Tibial external rotation test (Dial test)

Patient position- Prone.

Knee tested in 30 degree flexion and 90 degree flexion

Procedure- Hold the foot and externally rotate the knee on both sides. Compare the amount of external rotation present on both sides.

Interpretation- If the amount of external rotation on the affected side exceeds the other side by more than 10 degree then there is PLC injury.

External rotation recurvatum test

Patient position- Supine.

Joint position- Knee in full extension

Procedure- Examiner stands at the foot end of the examination couch. The limb is lifted up by holding the big toe which hill exert a varus-external rotation-extension stress on the knee. Assess the amount of hyperextension, external rotation and varus that is present on both limbs.

Interpretation- In patients with PLC injury, the affected knee goes into excessive varus hyperextension and external rotation in comparison to the opposite side.
 

Posterolateral external rotation drawer test

Patient position- Supine.

Hip flexed to 45 degree and the knee is flexed to 90 degree.

Externally rotate the foot and fix it by sitting over it while the hip flexed to 45 degree and the knee is flexed to 90 degree. Do a posterior drawer test. Repeat at 30 degree flexion of knee. Look for posterior subluxation of lateral tibial condyle.

Interpretation- If there is posterior subluxation of lateral tibial condyle when the test was done at 300 knee flexion and is absent at 900 flexion, then there is isolated PLC injury.

Posteromedial rotational instability test

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s