Examination of Knee Joint – Types, Technique, Procedure

Examination of Knee Joint/The knee examination, in medicine and physiotherapy, is performed as part of a physical examination, or when a patient presents with knee pain or a history that suggests a pathology of the knee joint.

The knee examination, in medicine and physiotherapy, is performed as part of a physical examination, or when a patient presents with knee pain or a history that suggests a pathology of the knee joint. The exam includes several parts: position lighting draping. inspection.

It is important to have a systemic plan for the examination of the knee to 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. Thorough knowledge of the normal anatomy, biomechanics of the knee and the pathology of various knee disorders is a must for proper examination of the 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 a wide range of anatomic and functional variations exist.
The 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 occupational and recreational activities.

HISTORY

Presenting complaints – Give the presenting complaints in chronological order.

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 the 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? The throbbing pain is due to inflammatory causes, burning pain is due to neuropathic causes.
• Radiation – Pain of the hip may radiate to the knee or thigh. Pain radiating below the 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 a patient gets up in the morning. The 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.

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 rigour, severity continued or intermittent and the treatment is taken.

History of trauma

• What was the mechanism of injury? Direct trauma
• Whether the foot was grounded or not?
• Any twisting or hyperextension of the 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 Dyscrasias
• 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, microphthalmos, cornea, pigmentation of the sclera.
• Pinna- Low set, blackish discolouration.
• Cheeks- Malar rash.
• Mouth – Normal dental hygiene, arch of the palate.
• Hair Line- Normal or low
• Neck – Webbing, thyroid swelling.
• Nipples- Normal level or not.
• The shape of the 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 the 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 degrees) with eversion of the foot.
• Neurocutaneous markers

INSPECTION

• Watch how the patient walks into the examination room. Is the gait normal? Is it painful? Is any deformity or shortening? Is there any incoming?
• 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 the quadriceps.
• Make the patient sit on a chair with the knee bend to 90 degrees. Observe the position of the 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 infra it will be more vertical.
• Make the patient lie supine on a couch. Look suprapatellar and parapatellar fullness. Observe the position of the 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 the 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 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 the 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 the appearance of pain and the resistance to the movement should be noted. In acute conditions, the pain appears before resistance to movement. The appearance of pain and resistance to movement appear together in subacute conditions. Resistance to movement occurs before the appearance of pain in chronic conditions.

MEASUREMENTS

Q Angle

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

Circumference

Measure the circumference at the following levels.

• 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 bounces 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 the 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 another hand on either side of the 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 the knee from the superolateral aspect of the 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. Effusion is graded as follows.
• Zero – No wave produced on downstroke
• Trace – Small wave on the medial side with a downstroke
• 1+ – Larger bulge on the medial side with dowstroke\2+ – Effusion spontaneously returns to the 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 the medial glide is less than 25% or <5mm, then there is tightness of the lateral patellar retinaculum. If the medial or lateral glide is more than 75%, then there is a laxity of the 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 the 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 the lateral border can be tilted less than normal then there is tightness of the lateral patellar retinaculum. If the medial border can be tilted more if there is laxity of the 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 the 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 the 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 the patella.
• Interpretation- Normally the patella progressively becomes 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 the trochlea and the position of the patella and the location of tibial tuberosity also influence patellar tracking. J sign is seen if the patella was laterally subluxated 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 of the patient with one hand. On the other hand, stabilize the knee and keep one finger on the joint line. To test for medial meniscus, apply 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. The 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 the 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. Another limb is off the ground. The examiner supports the patient by holding 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%, the positive predictive value of 98.5%, the negative predictive value of 86.0%, the 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 Sports 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 a foot in internal rotation indicate lateral meniscus lesion.

Duck walking test (Childress 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.

Merkel’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.

Peyer’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 the knee indicate medial meniscus lesion.

Helfet’s test

• Patient position – Seated on the couch with a 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 the 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 the medial meniscus.

Tests for ligamentous instability

Valgus stress test

• Purpose – To assess the structural integrity of the 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 the thumb is over the medial joint line to detect the amount of opening of the joint and the other fingers are on the lateral side to act as the fulcrum for the application of valgus stress. Bend the knee to 30 degrees 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 the knee there is an injury to the medial collateral ligament. If there is excessive opening up of medial joint space in 0 extensions as well as in 30-degree flexion, then there is an injury to the MCL and the cruciate ligaments. The laxity is graded as follows. 0-5mm opening in comparison to the opposite side. 5-10mm opening >10mm opening

Varus stress test

• Purpose – To assess the structural integrity of the 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 the thumb is over the lateral joint line to detect the amount of opening of the joint and the other fingers are on the medial side to act as the fulcrum for the application of varus stress. Bend the knee to 30 degrees 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 the knee there is an injury to the lateral collateral ligament. If there is the excessive opening up of lateral joint space in 0-degree extension then there is an injury to the LCL and the cruciate ligaments. The laxity is graded as follows.
• 0-5mm opening in comparison to the 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 degrees. Slight external rotation of the 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 endpoint is suggestive of anterior cruciate ligament injury. Excessive posterior translation of tibia, when compared to the opposite side with a soft endpoint, 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 the patellar tendon with the tip of the 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 falsely 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. The sensitivity of the test is between 20-40% in acute cases and between 40-70% in chronic cases. The 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 the 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 subluxated 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 the 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 subluxated posteriorly due to the effect of gravity. The active contraction of the quadriceps leads to the 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.

Actively resisted extension test

• Keep the knee in 150 flexions. Ask the patient to extend the knee against resistance.

Patellar reflex reduction test

• Keep the knee in 300 flexions. 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. On the other hand, support the limb with the palm over the posterolateral aspect of the 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 subdued and suddenly gets reduced beyond 30-degree flexion with a demonstrable thud. When the knee is flexed the iliotibial band passes posterior to the centre of rotation of the knee exerting a posterior pull reducing the anterior subluxation of the lateral tibial condyle.

Noye’s flexion rotation drawer test

Noyes glide pivot shift test

• Pivot shift test is 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 internal rotation stress on the knee leading to anterior subluxation of the lateral condyle of the tibia.
• Joint position – Knee in extension.\
• Procedure – Lift up the limb by holding the ankle with one hand to apply 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. On the other hand, support the limb with the palm over the lateral aspect of the 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 subdued 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 degrees 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 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.
• The hip flexed to 45 degrees and the knee is flexed to 90 degrees.
• Externally rotate the foot and fix it by sitting over it while the hip flexed to 45 degrees and the knee is flexed to 90 degrees. Do a posterior drawer test. Repeat at 30-degree flexion of the 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 flexions, then there is isolated PLC injury.

Posteromedial rotational instability test

Motion

Assessment of effusion

The absence of normal grooves around the patella may indicate a patellar intra-articular effusion. There are two ways to confirm the effusion. The knee is extended fully before the examination begins. This first way is the patellar tap. It is to squeeze the fluid between the patella and the femur by pressing at the medial patella using a non-dominant hand. Then, using the dominant hand to press on the patella vertically. If the patella is ballotable, then patellar intra-articular effusion is present. Another way is the milking of the patella. First, the effusion is milked at the medial border of the patella from the inferior to superior aspect. Then, using another hand, the effusion is milked at the lateral border of the patella from superior to inferior aspect. If the effusion is present, a bulge will be appearing at the medial border of the patella because the effusion is milked back to the medial patella.^[rx]

Assessment of range of motion

Both the active and passive range of motion should be assessed. The normal knee extension is between 0 to 10 degrees. The normal knee flexion is between 130 to 150 degrees. Any pain, abnormal movement, or crepitus of the patella should be noted. If there is pain or crepitus during active extension of the knee, while the patella is being compressed against the patellofemoral groove, patellofemoral pain syndrome or chondromalacia patellae should be suspected. Pain with active range of motion but no pain during passive range of motion is suggestive of inflammation of the tendon. Pain during active and passive range of motion is suggestive of pathology in the knee joint.^[rx]

Assessment of collateral ligaments

Valgus stress test can be performed with the examined knee in 25 degrees flexion to determine the integrity of the medial collateral ligament. Similarly, varus stress test can be performed to access the integrity of the lateral collateral ligament. The degree of collateral ligament sprain can also be assessed during the valgus and varus tests. In a first degree tear, the ligament has less than 5 mm laxity with a definite resistance when the knee is pulled. In a second degree sprain, there is laxity when the knee is tested at 25 degrees of flexion, but no laxity at extension with a definite resistance when the knee is pulled. In a third-degree tear, there will be 10 mm laxity with no definite resistance either with knee with full extension or flexion.^[rx]

Assessment of anterior cruciate ligament

The anterior drawer and Lachman tests can be used to access the integrity of the anterior cruciate ligament. In the anterior drawer test, the person being examined should lie down on their back (supine position) with the knee in 90 degrees flexion. The foot is secured on the bed with the examiner sitting on the foot. The tibia is then pulled forward by using both hands. If the anterior movement of the affected knee is greater than the unaffected knee, then the anterior drawer test is positive. The Lachman test is more sensitive than the anterior drawer test. For the Lachman test, the person lies down in a supine position with the knee flexed at 20 degrees and the heel touching the bed. The tibia is then pulled forward. If there are 6 to 8 millimetres of laxity, with no definitive resistance when the knee is pulled, then the test is positive thus raising concern for a torn anterior cruciate ligament. A large collection of blood in the knee can be associated with bony fractures and cruciate ligament tear.^[rx]

Assessment of posterior cruciate ligament

Posterior drawer test and tibial sag tests can determine the integrity of the posterior cruciate ligament. Similar to the anterior drawer test, the knee should be flexed 90 degrees and the tibia is pushed backwards. If the tibia can be pushed posteriorly, then the posterior drawer test is positive. In the tibial sag test, both knees are flexed at 90 degrees with the person in the supine position and bilateral feet touching the bed. Bilateral knees are then watched for the posterior displacement of the tibia. If the affected tibia slowly displaced posteriorly, the posterior cruciate ligament is affected.^[rx]

Assessment of meniscus

Those with meniscal injuries may report symptoms such as clicking, catching, or locking of knees. Apart from joint line tenderness, there are three other methods of accessing meniscus tear: the McMurray test, the Thessaly test, and the Apley grind test. In the McMurray test, the person should lie down in a supine position with the knee should in 90 degrees flexion. the examiner put one hand with the thumb and the index finger on the medial and lateral joint lines respectively. Another hand is used to control the heel. To test the medial meniscus, the hand at the heel applies a valgus force and externally rotate the leg while extending the knee. To test for the lateral meniscus, the varus force, internal rotation are applied to the leg while extending the knee. Any clicking, popping, or catching at the respective joint line indicates the corresponding meniscal tear.^[rx]

In the Apley compression test, the person lie down in a prone position with the knee flexed at 90 degrees. One hand is used to stabilise the hip and another hand grasp the foot and apply a downward compression force while external and internal rotates the leg. Pain during compression indicates meniscal tear. Examination for anterior cruciate ligament tear should be done for those with meniscal tear because these two conditions often occur together.^[rx]

References