examination of knee joint.docx

7/29/2019 examination of knee joint.docx

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P. NEYRET, G. LE BLAY, T. AIT SI SELMI

Centre Livet, Department of Orthopaedic Surgery - F-69300 Caluire

We owe our knowledge in this field to Henri Dejour. Our grateful thanks are due toMatrise Orthopdique for providing us with the opportunity to translate what has so farbeen an oral tradition into a written record.

This review article is intended to familiarize orthopaedic surgeons with the methodologyrequired for a systematic and logical examination of the knee joint.

The knee needs to be examined systematically, since so much can go wrong with theknee, and so many signs and symptoms may be produced, that only a systematic techniquewill ensure that nothing of importance is missed.

Equally, a logical approach is required, since the best way to remember a technique is toknow why it is being applied. We will, therefore, attempt to explain what the various signsand symptoms mean in terms of knee pathology or pathophysiology.

The detailed examination of the knee will need to be preceded by taking the patient'shistory. This aspect of the clinical approach is vital, since it will often be found that a

properly taken history will permit at least a presumptive diagnosis to be made. In fact, wemight go so far as to say that good history-taking is "non-invasive arthroscopy."

This article also presents the IKDC (International Knee Documentation Committee) KneeEvaluation Form, under the various headings, in order to allow the more junior surgeons tofamiliarize themselves with international rating systems. The IKDC form itself was explainedby P. Chistel, in the Revue de Chirurgie Orthopdique (1993, 79:473). It is used mainly inanterior cruciate ligament (ACL) surgery, to facilitate comparisons of results obtained indifferent studies of knee ligament trauma, in Europe and in the United States.

1 - HISTORY-TAKING

After establishing the nature of the principal complaint (or reason for consulting a doctor), asystematic history should be obtained, with questions grouped under three headings: History of

present complaint; signs and symptoms; and life style (level of activity).

No. 1 HISTORY OF PRESENT COMPLAINT


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As a rule, three questions should suffice to obtain all the information required under this heading.

The first two concern the onset of the present complaint.

1.1 When?This first question allows the examiner to distinguish between two patterns - complaints with an

identifiable starting point, a known accident (traumatic or post-traumatic knee disorders); andcomplaints that appear to have come on more insidiously, which would be more suggestive of

inflammatory or degenerative disease.

1.2 How?The examiner should try to elicit the exact circumstances of how the disorder occurred -

obtaining a description of how the accident happened or of how the problem has developed overtime. Thus, in a trauma case, the examiner would seek to find out the nature of the contact

(violent/non-violent; in valgus; in varus; in hyperextension) or whether the knee "went" after

kicking a ball or "missing a kick." It would also be important to establish whether there was an

audible "pop" in the joint, whether the knee swelled rapidly, and whether the athlete needed help

to come off the pitch: - An affirmative answer to these questions would be highly suggestive of atorn ACL (Figs. 1-5).

Figure 2 Figure 3


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Figure 4 Figure 1 Figure 5

1.3 What happened after that?This question needs to be asked in order to obtain information on any medical or surgical

treatments already applied, on rehabilitation (if any), and on the course of the condition up to the

time of consultation.

No. 2 SIGNS AND SYMPTOMS

A complete picture of the patient's signs and symptoms should be obtained, since anything

elicited under this heading may be of diagnostic value.

There are four categories of cardinal signs and symptoms in the knee joint:-

2.1 PainThe examiner should establish the way in which the pain developed, its character, and its

severity; the patient should be asked to point to the site of the pain.

Pain at night suggests an inflammatory cause, while pain that gets worse towards evening, or

during/after exercise, would be more likely to be mechanical in origin.

Pain when going up or down stairs, or aching in positions where the knee is kept flexed for

prolonged periods of time (car journeys, visits to the cinema), are indicative of patellar problems,while pain that occurs when the knee is hyperflexed is usually caused by meniscal pathology.

The patient should also be questioned about pain in other parts of the body (low back pain, hip

pain).

Bar- or vice-like pain below the patella is highly suggestive of a low-riding patella.


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2.2 LaxityA certain amount of confusion has occurred in the international literature, since the French usethe term instabilit to denote what in English would be called laxity, and speak of laxit in the

sense of the English term instability.

"Going out": This is the term used by many lay persons to describe what will usually be found

to be a torn ACL or a dislocation of the patella.

"Giving way": This term is used to describe the sensation of the knee suddenly failing to

provide proper support, especially when walking on uneven ground. The symptom may be due tothree mechanisms:

- Interposition: If, during weight-bearing, a third structure (meniscus, synovial membrane,

cartilage, etc.) is placed between the opposing cartilage surfaces of the joint, a protective reflexwill be triggered. This reflex will make the quadriceps relax and unlock the knee, to allow the

joint to clear itself.

- Cartilage damage: If one or both of the cartilage surfaces are damaged, and the surfaces come

into contact, the quadriceps may also be made to relax.

- Muscle weakness: This may occur in quadriceps wasting, in polio, after surgery, etc.

2.3 LockingA proper knowledge of this clinical feature is vital, since patients have often been misdiagnosed

because of the examining physician's imperfect understanding of this symptom. There are two

types of locking, which must be carefully distinguished:

Meniscal locking (true locking): This is what a physician would consider to be locking. It isthe impossibility fully to extend the knee for an appreciable period of time (more than a few

minutes). This "passive flexion deformity" is brought on by a mechanical obstacle which makes

the knee stop short of full extension (Fig. 6). The cause may be a bucket-handle tear of themeniscus, or a bulky flap that has dislocated forwards in the joint; a loose body or an ACL stumpmay also be to blame.

Patellar catching (false locking): This is what the patient would consider to be locking. It is a

momentary "sticking" of the knee, during a flexion-extension movement, with the knee incapable

of flexing or extending beyond that particular point. Catching is relieved as soon as weight istransferred to the other side (Fig. 7). Usually, patellar cartilage damage will be found to havecaused this fleeting episode of "locking."


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Figure 6 Figure 7

2.4 EffusionThe knee swells up. Swelling of the knee is always indicative of a genuine lesion of the joint.

Sometimes, its character will already have been established by aspirating the joint. The features

of the aspirated fluid (colour, viscosity, protein content, cellularity) make it possible to ascertainwhether the condition is mechanical or inflammatory; a search for microcrystals should always

be made.

Hydroarthrosis: The accumulation of clear, straw-coloured fluid is the result of irritation of the

synovial membrane, which may be primary (inflammatory disease) or secondary to cartilage

damage (osteoarthritis), meniscal lesions, or the presence of a loose body (osteochondritis

dissecans; osteochondral fractures). Hydroarthrosis may also be seen following ligament lesions.

Blood in the joint (haemarthrosis) without a history of trauma could mean two things:

haemophilic arthropathy, or pigmented villonodular synovitis. In the latter condition, the fluidmay be amber-coloured rather than frankly bloody (Fig. 8).


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Figure 8

2.5 Other clinical features

Subjective sensation of internal derangement: The patient feels that there is something

moving in the knee (joint mouse); something "funny"; "a lump." This feature suggests a meniscallesion or a loose body.

Noises in the joint: Crepitus is a faintly audible and often palpable sensation of grating duringflexion-extension. Clunks and clicks are much louder, and suggestive of meniscal lesions.

For evaluation with the IKDC score, the patient will need to indicate the highest activity levelthat his or her knee will tolerate, even if (s)he does not practise the activities at that level. The

levels are as follows:-

I - Strenuous activity

(contact sports involving pivoting and cutting)

II - Moderate activity(pivot sports without contact; manual work)

III - Light activity(jogging, running)

IV - Sedentary activity

Patients who report symptoms at level I but not at level II are rated B = "nearly normal."

The lowest grade within a group determines whether the patient is group-graded A, B, C, or D inthe last column in Table 1.

Table 1


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No. 3 LEVEL OF ACTIVITY

History-taking also involves obtaining information on the patient's present and desired levels of

activity. This information is important for two reasons: Firstly, it gives an idea of the degree of

disability produced by the knee disorder; and, secondly, it shows what the patient would like tobe able to do with his or her knee.

The questions to be asked will be a function of the patient's age:

Young, active, or athletic patients should be questioned about the sports they practise, andabout their ability to run, jump, or cut.

Elderly or sedentary subjects should be asked about the use of walking aids, their walkingdistance, ability to go up and down stairs without holding on to a handrail, and whether they can

get up from a sitting position without using their hands.

2 - EXAMINATION

The patient should be examined standing up, walking, and lying supine. It is essential that a

comparison be made throughout with the unaffected side.

1 - In the STANDING PATIENT, a study should be made of

Lower limb pattern: The lower limb is said to be in normal alignment if, when seen head-on,

with the patellae pointing forwards, the medial malleoli and the femoral condyles touch. Genuvarum describes a condition in which the femoral condyles are apart when the feet are together,

while in genu valgum the ankles are separated when the knees touch. The distances should bemeasured; they may be expressed in centimetres (or in fingerbreadths), with the knees in

extension (Figs. 9-10). With the knees in hyperextension, a varus deformity may be seen to

worsen. Genu varum and genu valgum are not, in themselves, abnormal conditions. This is why

"normally aligned" is not synonymous with "normal."


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Figure 9 Figure 10

Muscle wasting: With the patient standing "to attention",. the muscle bulk is checked.Quadriceps wasting shows up as wasting of the vastus medialis. Looking at the vastus medialis

will give an immediate idea of whether the quadriceps is wasted. Wasting may be the result of

under-use of the knee joint. It may be quantified by measuring the circumference of the thigh.

2 - In the WALKING PATIENT, the following features are checked:-

The toeing angle is the angle between the axis of the foot and the direction in which the

subject is walking. Normally, the axis will be seen to point in a slightly lateral direction,

enclosing an angle of 10 to 15. In the normal postural pattern, this angle will be the same on

both sides.

Tilting of the knee with single-leg stance: This is seen where bone wear has occurred as aresult of osteoarthritis (OA). The feature does not manifest itself until several years have elapsed.

Where the tilt is due to ligamentous problems, it will be seen early on.

(a) With wear in the medial compartment, the tilt will chiefly be into varus, in a position of near-

extension. It is best seen from behind the patient (Fig. 11).


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Figure 11

(b) With lateral compartment wear, on the other hand, the tilt will be into valgus and flexion; it isbest appreciated from in front.

(c)A tilt into recurvatum is rare; it is not well tolerated by the patient.

3 - EXAMINATION OF THE SUPINE PATIENT

3.1 General appearanceThere are two cardinal features with which the examiner has to be familiar, since they are as

important in the examination of the knee joint as the temperature and pulse rate are in the generalexamination of a patient. They make it possible for a "spot diagnosis" of a genuine, organic knee

lesion to be made by the examiner.

(a) Looking for an effusion: The examiner's hands are placed on either side of the patella, with

the thumb and middle to little fingers stroking the synovial fluid towards the patella, while the

index finger is used to elicit the patellar tap: The patella is at first pressed down and submerged

under the synovial fluid, and will strike the trochlea, producing a tap. As the pressure is relieved,the patella will bob up like an ice cube in a drink(Fig. 12).

(b) Looking for a fixed flexion deformity: The patient is positioned supine and made to relax.

The examiner grasps both the patient's heels and supports them at a height of 10 cm above the

examination couch. This is the best position for screening for a flexion deformity, which is a

major feature of knee pathology. This sensitive and straightforward method is ideal for screeningpurposes. It does not, however, lend itself to a quantification (in degrees) of the deformity. Also,

since the patient's feet are braced against the examiner's abdomen, the examiner may seek to

reduce the flexion deformity by pressing down on the patient's knees (Fig. 13).


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Figure 12

Figure 13

- Knee pattern in the supine patient: As the patient goes from two-legged stance into the

supine position, the deformity may or may not correct itself. If a lower limb malalignment was

found with the patient standing on both feet, the examiner should check whether the deformitycan be reduced in the supine patient, which would suggest that the deformity is articular (rather

than extra-articular and bony) in origin.

Another way of checking for a flexion deformity consists in positioning the patient prone, on a

firm table, with the knees supported on the table and the legs protruding beyond the table's edge.

One heel is seen to be higher than the other. The distance between the two heels may bemeasured. It provides direct evidence of the flexion deformity. The test is reproducible, and the

result is numerical (in cm). However, it requires a firm surface, and the patient must be

positioned prone (Fig. 14).


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Figure 14

In order to be able to tell whether a finding is abnormal, the affected side will have to becompared with the presumably healthy limb (the reference knee). This comparison will show

whether there is a fixed flexion deformity or a genu recurvatum.

- The range of movement (ROM) is tested at this stage of the examination (which also involves

screening for quadriceps wasting). Three figures are used to denote the ROM. The first indicates

flexion; the second, full extension; and the third, recurvatum.

Thus, 140, 0, 5 means that flexion is 140; the knee can be extended fully; and there is 5 of

recurvatum. 120, 5, 0 would mean that flexion is 120, there is a flexion deformity of 5; and no

recurvatum.

For evaluation with the IKDC score, the passive ROM is recorded in both knees. Values aregiven in 3-figure form: Extension/Flexion / Lack of extension (from 0) / Lack of flexion (Fig.

15) (Table 2).


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Figure 15

Table 2

3.2 Extensor apparatus

Inspection- The bayonet sign: This term describes the pattern produced by the patella, the patellar tendon,

and the tibial tubercle. The line resembles a bayonet fixed to a rifle.

Pathophysiology: The bayonet results from a lateral position of the tibial tubercle. It was

thought for a long time that this was an organic factor contributing to patellar instability. It is

now known that it is the resultant of the forces produced by the lateral position of the tibialtubercle that tends to pull the patella sideways.

Reliability: Not very good. A more reliable picture may be obtained from measuring the

distance from the tibial tubercle to the inside of the trochlea on CT scans.

- Squinting of the patella

Palpation- Looking for tender points is particularly useful if the patient has also reported symptoms of

pain (Fig. 16).

* Tibial tubercle: In adolescents, the tibial tubercle may be affected by apophysitis, with

fragmentation of the apophysis (the accessory ossification centre). The patient will complain of

pain in the tibial tubercle, and the examiner will be able to elicit tenderness over that structure(Osgood-Schlatter disease).

* Patellar tendon: This structure may be the site of repetitive strain injuries (jumper's knee); thepatient will complain of pain in the patellar tendon, and extension against resistance will be

painful.


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* Apex of the patella: In adolescents, inflammation of the distal pole of the patella may occur as

a very rare condition (Sinding-Larsen-Johansson syndrome).

* Medial facet of the patella (Fig. 17a): The medial facet of the patella may be tender to

palpation, and the patient may report pain at that site. The feature is usually part of an anterior

knee pain syndrome.

* Lateral facet of the patella (Fig. 17b): The examiner pushes the patella in a lateral direction,and palpates the lateral facet. Patellofemoral dysplasia will produce lateral impingement and pain

and tenderness along the lateral border.

Figure 16 Figure 17

* A search should also be made for a mediopatellar plica, which appears as a tender cord thatrolls under the palpating finger, on the medial femoral condyle. It sweeps along the condyle

during flexion, and may give rise to pain symptoms.

* Patellar tilt: The examiner holds the edges of the patella between the thumb and index finger,

thereby establishing the axis of the patella, which should differ only slightly (10 lateral tilt)

from the horizontal plane of the knee seen head-on.

The patella may be said to squint (convergent or divergent squint) (Fig. 18). Broadly speaking, aconvergent squint tends to occur in anterior knee pain syndrome, while a divergent squint would

be more likely in recurrent dislocation.


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Figure 18

Patellar tests

- Apprehension signThe patient is positioned supine, with the knee flexed between 0 and 30. The examiner firmlypushes the patella in a lateral direction. The patient, who knows and apprehends the dislocation

that will be produced by this manoeuvre, will stop the examiner. Results are recorded as + or 0.

Pathophysiology: Between 0 and 30 of flexion, the patella is at its highest point in the

trochlea. Pressure from the medial side will push the patella in a lateral direction, causing it to

dislocate from the trochlear groove. This will cause not only pain, but apprehension on the part

of the patient (Fig. 19).

This sign may be elicited in recurrent dislocation; it is highly suggestive, and particularly usefulin patella alta. As Henri Dejour puts it, "You can't get near their kneecaps." (Fig. 20)


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Figure 19 Figure 20

The test must be stringently performed and analyzed.

- Patellar grind testThe examiner's hand is placed on the front of the knee. The patient performs flexion-extension.The examiner will feel a crepitus, and may even notice the patella catching. The crepitus is

difficult to interpret. If there is nothing more than a positive grind test, a diagnosis of OA or of

cartilage damage cannot be made.

Patellofemoral joint crepitus should be sought over the entire ROM from flexion to extension,

against slight resistance. Crepitus in the tibiofemoral compartments is sought from flexion to

extension, against resistance, as well as in valgus-flexion-external rotation (to test the lateralcompartment) and in varus-flexion-internal rotation (to elicit medial compartment crepitus).

Gradation depends on the loudness of the crepitus and on the pain produced by the manoeuvre(Table 3).

Table 3


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3.3 The menisci

Broadly speaking, the menisci should be examined with the knee in flexion. There must be

tenderness (i.e. the patient must respond to palpation with pain). There are various ways in which

the sensitivity of the tests can be enhanced. However, all the tests for meniscal lesions rely on the

same principle: Stressing an injured medial or lateral meniscus will cause pain.

Tenderness to palpation is elicited with the knee flexed 90 and the patient's foot resting onthe table. The examiner's index finger probes the meniscus along the joint line. The most

frequently encountered sites of tenderness are over or behind the medial collateral ligament, at

the medial meniscal tender point (Fig. 21). Less often the tender point will be anterior, in whichcase the phenomenon may be part of a patellar disorder, a bucket-handle tear of the medial

meniscus, or a lesion of the anterior horn of the lateral meniscus. The lateral meniscal tender

point may be anywhere along the joint line (Fig. 22).

Figure 21


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Figure 22

Meniscal tenderness on mobilization: Compression of the different parts of the meniscus bythe femoral condyle occurs as the meniscus glides backwards on the condyle during flexion, and

forwards during extension.

This means that the posterior horn will be compressed when the knee is in hyperflexion (Fig.23); while the anterior horn will be compressed in hyperextension.

The diagnostic accuracy of the tests is improved by adding a component of tibial rotation to the

simple flexion-extension manoeuvres. This rotation tends to bring the posterior horns forward.

Medial pain will be elicited in external rotation, and lateral pain in internal rotation.

- McMurray's test: Forced flexion and external rotation with compression of the medial joint

line will elicit pain in the medial meniscus. The hand pressed over the joint line will feel a click.The test may be reversed, to examine the lateral meniscus.

- Apley's grinding test: For this test, the patient is positioned prone, with his or her knee flexed.Compression and external or internal rotation may be painful, showing that the medial or the

lateral meniscus are torn. This test is always checked, by performing rotation without

compression. This manoeuvre should not cause discomfort, unless the collateral ligaments are

affected (Fig. 24).

Figure 23 Figure 24

- Cabot's manoeuvre: The heel is placed on the tibial crest of the opposite leg. The knee is

gradually flexed, while the heel runs along the tibial crest. This movement may produce lateral

pain, when the knee is in 90 of flexion with the heel resting on the other leg (Cabot's position).The lateral compartment is distracted by pressure on the medial side of the knee; this, too, may

be painful.


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Cysts of the lateral meniscus will be seen in extension, and disappear in flexion. They are on

or near the lateral joint line. They are best seen in semiflexion. The cysts will disappear inhyperflexion, and reappear as the knee is gradually extended; in full extension, they will once

again be out of sight.

(In children, a malformation of the lateral meniscus may give rise to snapping when the knee istaken through flexion and extension. This abnormal movement is associated with a clicking

noise, which may be very pronounced.)

3.4 Stability testing

3.4.1. Medial/lateral instability in extension

(a) Medial instability in extension

The examiner grasps the patient's heel (not the ankle or the leg) with one hand, while the otherhand is placed against the lateral aspect of the patient's knee. A brisk valgus stress is impartedand immediately released. Medial instability is demonstrated if the medial joint line opens up

(Fig. 25). Sometimes the most characteristic phenomenon is a little click as the knee reduces

after the stress test. Sometimes, it is difficult to decide whether there is instability.

Figure 25

Several points need to be borne in mind: The abnormal feature is the asymmetrical pattern of the instability. The examiner may also ask

the patient, "Do you think your right knee is different from your left knee?"

The leg may be supported halfway between the knee and the ankle, by pressing it against the

examiner's body. That way, a greater valgus thrust may be applied. The third point of support

produces better leverage.


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The instability will be due to a lesion of the ligaments on the medial side and/or to medial

tibiofemoral compartment wear.

(b) Lateral instability in extension

The examiner grasps the patient's heel with one hand, while exerting pressure against the insideof the knee with the other hand. The varus stress applied will cause lateral gaping in the laterally

unstable knee. Lateral joint gaping is physiological. It is the asymmetry of the gaping thatconstitutes the abnormal finding.

3.4.2. Medial/lateral instability in 30 flexion

Description: The leg is held as described above, but the knee is unlocked by putting it in 20-30

flexion.

(a) Medial instability

The movement imparted is one of valgus-flexion rather than valgus-flexion-external rotation.Instability in valgus-flexion-external rotation would be a sign of an injured medial collateral

ligament.

(b) Lateral instabilityVarus-flexion-internal rotation is used to investigate the lateral collateral ligaments. Once again,

asymmetry would have to be demonstrated to qualify the result as abnormal (Fig. 26).

Figure 26

In the United States, examiners prefer to sit on the couch, between the patient's knees, for theperformance of this test (Fig. 27).

The lateral collateral ligament is palpated with the knee in Cabot's position (see above), where itwill be felt as a tense band. It is possible to explore both knees simultaneously, with the patient

in the "frog position" described by Henri Dejour (Fig. 28).


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Figure 27 Figure 28

3.4.3. Anterior instability

(a) Lachman-Trillat testIt is important to ensure that the patient is relaxed. This is all the more vital in recent traumacases. In order to obtain relaxation, the patient is made to rest his or her head on the couch. It

may be useful to roll the thigh in and out, to get the muscles to relax (Fig. 29).

For the test, the knee is unlocked in 20 flexion. The patient's heel rests on the couch. The

examiner holds the patient's tibia, with the thumb on the tibial tubercle. The examiner's other

hand is placed on the patient's thigh, a few centimetres above the patella. The hand on the tibia

applies a brisk anteriorly directed force to the tibia (Fig. 30).

Figure 29 Figure 30


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The quality of the endpoint at the end of the movement is described as either "firm" or "soft."

Grading depends on the quality of the endpoint observed, and on whether there is a difference of3-5 mm between the affected and the unaffected knee. A soft endpoint will make the grading

"abnormal" rather than "nearly normal."

If the movement of the tibia on the femur comes to a sudden stop, this is described as a firmendpoint. If it does not, the endpoint is described as soft. A soft endpoint is pathognomonic of a

torn ACL. It is easier to demonstrate a firm endpoint, which is also recognized by the patient. Ifthe ACL is torn in one knee, the patient will be perfectly aware of the difference between the

firm endpoint in the healthy, and the soft endpoint in the cruciate-deficient knee. Sometimes, the

endpoint will be firm, but translation will be seen to be asymmetrical. This is known as a"delayed firm endpoint" (increased excursion and a good endpoint). It is indicative of a torn and

partially healed ACL (ACL adherent to PCL), of a stretched ACL graft, or a torn PCL (changing

the "starting point" of the test). A firm endpoint results from the sudden tensioning of the ACL

(Fig. 31). The test is of lesser value in knees affected by OA, with a large number of osteophytes.

Figure 31

Lachman used to perform the test with the thumb of the distal hand on the medial joint line, so asto feel the displacement of the tibia on the femur.

In Trillat's modification of the test, the thumb is placed on the tibial tubercle, so as to get visualevidence of the translation. In our practice, we prefer Trillat's method.

The Lachman-Trillat test, the drawer test in 70 flexion, and the medial and lateral joint openingtests may be performed manually or using an arthrometer (KT-1000, KT-2000) or stress

radiography. If an arthrometer is used, a force of 134 N (30 lbs.) will need to be applied.

Measurements are performed on both sides. The difference between the affected side and theopposite side is recorded. Usually, only one value is recorded. The absolute value is also of

interest, and should be recorded for prospective study purposes.


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If, after ACL surgery, the operated side is found to be tighter than the healthy side, the graft will

be at increased risk of failure.

Active resisted extensionIn obese patients or subjects with bulky muscles, it may be difficult for the examiner to encircle

the patient's thigh with his or her hand. In such cases, the examiner may place a fist under theknee, hold the ankle against the couch with the other hand, and ask the patient to lift the leg

against resistance (Fig. 31b). This resisted quad setting will move the tibial tubercle forward.This is a useful screening test, which will not, however, be positive unless there is major

instability. It would be preferable to obtain stress radiographs (134 N stress) on which to base the

diagnosis.

Figure 31b

(c) Pivot shiftsTests screening for pivot shift were first described by M. Lemaire, in 1968. Since then, manysuch tests have been devised, of which we shall only list the main ones. According to Noyes, the

phenomenon is potentiated when the hip is abducted. At present, attempts are being made to

substantiate the diagnostic value of these tests. However, they should not be expected to providemore than they can: A shift means that the ACL has gone. Sometimes, though, the ACL may be

deficient without a pivot shift occurring during the relevant tests.

Screening for pivot shift must be done systematically, using the customary techniques. The

IKDC form records only the greatest shift found. The scoring system is conventional: + = glide;

++ = clunk; +++ = gross.

- Pivot shift in extension (Dejour's test) (1978)Description:

(1) The patient's foot is wedged between the body and the elbow of the examiner. The examiner

places one hand flat under the patient's tibia, pushing it forwards (force applied in an anterior

direction), with the knee in extension. The other hand is placed against the patient's thigh,pushing the other way (force applied in a posterior direction) (Fig. 32).


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Figure 32

(2) The lower limb is taken into slight abduction, by the examiner's elbow, with the examiner'sbody acting as a fulcrum to produce the valgus.

(3) The examiner maintains the anterior tibial translation and the valgus, and imparts flexion.

At 20-30 flexion, pivot shifting will occur, with a clunk as the lateral tibial plateau suddenly

reduces (Fig. 33).

Figure 33

Significance: The valgus stress associated with the anterior tibial drawer makes the lateral tibialplateau sublux on the lateral femoral condyle and compresses the structures. The sudden

reduction of the convex lateral tibial plateau compressed under the lateral condyle is responsible

for the clunk. Sometimes, a clunk may be elicited with compression, rather than any major


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valgus stress. The pivot shift is easy to produce, and causes no discomfort. It is a mixture of shift

and Lachman, and provides evidence of ACL tears and damage to posteromedial structures.

- The glide pivot shift test described by Henri Dejour is the equivalent of Noyes' test. It

produces a glide (a minor form of shift) rather than a proper clunk. The patient is unaware of the

slip of the plateaus on the femoral condyles. The valgus component is less pronounced than arethe compression and anterior drawer applied by the examiner. It produces joint play rather than a

pivot shift. It can be seen in patients with a torn and partially healed ACL, as well as after ACLgrafts or other ACL surgery (Fig. 34).

Figure 34

- The pivot shift test of MacIntosh

"When I pivot, my knee shifts." This is how a hockey player described his symptoms - hence thename of the test.

MacIntosh realized that the sensation of shifting or slipping was related to rupture of the ACL.

He devised a test to reproduce the sensation reported by patients, involving stress applied to the

knee in valgus and flexion, with or without internal rotation (Fig. 35).


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Figure 35

Description of the test: The patient is positioned supine, with the examiner standing on theaffected side. The examiner uses one hand to hold the patient's foot in very slight internal

rotation. With the other hand, (s)he applies a valgus stress to the posterolateral aspect of the

proximal calf. At this point, flexion is started. The lateral tibial plateau will be seen to sublux

forwards during the first degrees of flexion. As flexion progresses, the anterolaterally subluxedtibia will suddenly reduce, at 30 of flexion. This reduction is associated with a characteristic

clunk, which the patient will readily recognize.

- Hughston's jerk testThe patient is positioned supine, with the examiner holding the lower limb in such a way as to

have the hip flexed 45, the knee flexed 90, and the leg in internal rotation. The distal hand

grasps the foot and places it in internal rotation, while the left hand applies valgus stress to theupper end of the leg.

A jerk is defined as a sudden change in the relationship between the joint surfaces. The

phenomenon occurs as the subluxation reduces near full extension.

Hughston thought that rotational phenomena were more important (hence his defence of the

concept of rotary instability).

- Slocum's ALRI test (1976)The patient is placed in a semilateral position, with the knee unsupported, and the lower limb

resting only on its heel. This allows internal rotation of the foot, to produce translation of thelateral tibial plateau. The examiner stands behind the patient's back, with the distal hand holding

the upper end of the leg, and the proximal hand around the lower end of the thigh. The test is

started in extension, using vertical pressure. Next, flexion is commenced. Translation occurs at20, and the pivot shifts at 40 (Fig. 36).


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Figure 36

- Losee's test (1969)Over the years, Losee has described five tests: The first is identical with the MacIntosh test; the

second uses external rotation of the tibia to elicit the pivot shift; the third (deceleration test) uses

the quadriceps slingshot effect; while the fourth and the fifth test the anti-pivot shift effect of

extra-articular ligament reconstructions.

(c) Anterior drawer in 90 flexion, or direct anterior drawerThe examiner sits on the patient's foot, which has been placed in neutral position. The knee is in

90 flexion. The index fingers are used to check that the hamstrings are relaxed, while the other

fingers encircle the upper end of the tibia and push the tibia forwards (Fig. 37).

Figure 37

If a direct anterior drawer is obtained, the ACL will be torn. However, for this sign to be elicited,

peripheral structures such as the medial meniscus or the meniscotibial ligament must also be


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damaged. This ligament forms a wedge, in 90 flexion, preventing anterior tibial translation. The

finding of an anterior drawer is conclusive evidence of an ACL tear. However, not every ACLtear will be associated with a positive anterior drawer test.

Drawer in external rotation (foot in external rotation). This test examines the posteromedial

structures (posteromedial corner, posterior horn of medial meniscus). The results are recorded as+++/0.

Drawer in internal rotation (foot in internal rotation). The diagnostic value of this test is less

well established.

Table 4

One-leg hop functional test (Dale Daniel)This test investigates the greatest distance the patient can hop on one leg.

The test is performed three times, and the mean value achieved is recorded. It is a comparative

test, the result of which is expressed as a percentage of the value achieved on the healthy side.

Table 5

3.4.4. Posterior instability

- Posterior tibial sag in 90 flexionIn the IKDC form, the posterior tibial sag is recorded in 70 flexion; a comparison is made with


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the opposite side, looking sideways at the knees to establish the amount by which the tibial

tubercle has dropped backwards. Posterior tibial translation may be confirmed if it is seen thatquadriceps contraction pulls the tibia forward.

- Straight posterior drawer

With the patient supine, the test is performed with the knee in 70-90 flexion and the foot inneutral rotation. The examiner sits on the patient's foot, placing both thumbs on the tibial

tubercle, and pushing the tibia backwards. A positive test (i.e. one in which the tibial plateaumoves in a posterior direction) means that the PCL is torn.

Oddly enough, this is a difficult test to perform, since the patient's tibia may often sagspontaneously, requiring this posterior translation to be reduced before the test is started, since

otherwise the result may be erroneously given as an anterior drawer. The quality of the endpoint

(firm or soft) is of no significance in the posterior drawer test.

To check the knee pattern, the knees should be inspected side-on, to see whether the tibial

tubercle has sagged backwards. The knees should be in 90 flexion, with the patient's feet restingon the couch. It is preferable to use Godfrey's drop back test.

There are three tests that can be used to demonstrate a posterior drawer, and which may beresorted to in case of doubt:

- Godfrey's drop back test: The patient is supine, with the thighs and knees flexed 90, legshorizontal, and heels held by the examiner in such a way as to have the legs parallel to the table.

The test is positive if the upper end of the tibia on the affected side is seen to drop backwards

(Fig. 38).

Figure 38

- Muller's test: Patient positioning is identical to that for the posterior drawer test in 90 flexion.Tibial sag is observed. The patient is asked to set his or her quadriceps: Before the heel will have

had time to lift off the couch, the posterior displacement of the tibia will have reduced.


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- Active extension against resistance: This is the same as Muller's test, but in 20 of flexion.

This test is of lesser practical value.

- Posterior drawer in external rotationThe foot is placed in external rotation. This test is equivalent to the straight posterior drawer test

in patients with PCL deficiency. The result is more pronounced in cases of posterolateral lesions.

- Posterior drawer in internal rotationThe foot is placed in internal rotation. Translation is usually 4 mm less than in the straight

posterior drawer test. If the same value is obtained, this would be indicative of a lesion of the

medial meniscofemoral or even the medial collateral ligament.

- Whipple's test: In order to rule out tibial translation as a result of gravitational sag, the patient

should preferably be examined prone. "This test is difficult. It has not yet gained wideacceptance." (B. Moyen). The information provided is the same as that obtained with the

conventional posterior drawer test performed with the patient supine, feet resting on the couch.

Apart from the fact that sag is eliminated, this test is completely unconstrained.

- Posterior translation in 20 flexion: Posterior displacement may be observed with the knee in

20 of flexion. If the result is the same as that of the straight posterior drawer test, there will beassociated posterolateral lesions.

3.4.5. Posterolateral instability

(a) External rotation recurvatum testDescription: The patient is supine. The examiner stands at the foot of the couch, and grasps the

patient's big toes, lifting the feet off the couch. The affected knee will go into varum-plus-

recurvatum (Fig. 39).

Figure 39


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According to Hughston, this test provides information on major disabling peripheral instabilities;

it cannot be positive unless the PCL is also torn: A positive recurvatum test shows that at leastone cruciate is torn and that there is a posterolateral lesion. Of the cruciates, the ACL is more

often involved than the PCL.

(b) Jakob test (reverse pivot shift test)The patient lies supine. The examiner stands at the patient's feet, and places his or her distal hand

on the patient's ankle, with the patient's leg braced against the examiner's pelvis. The proximalhand supports the upper third of the calf on the lateral side, and imparts a valgus force so as to

compress the lateral compartment. The lateral tibial plateau will drop back under its own weight,

with the foot in external rotation.

This test starts with the knee in flexion. The joint is gradually taken into extension by its own

weight.

At a given point, the subluxation will reduce with a snap, and the foot will go into neutral

rotation. The test involves a pivot shift manoeuvre, but since it starts from a subluxed position ofthe lateral tibial plateau, with reduction in extension, it is known as a reverse test.

The jolt is produced by the reduction of the posterior subluxation through the action of the lateralhead of the gastrocnemius, the capsule, and the pull of the iliotibial band, which, past 40 of

flexion, moves from a flexor to an extensor function. All these factors will tend to pull the tibialplateau forward, out of its posteriorly subluxed position. Since there cannot be any rolling-

sliding, the plateau will snap back into reduction.

Significance: This test provides evidence of a posterolateral instability which may or may not be

associated with a lesion of the PCL. The test is not very specific.

Posterior subluxation of the lateral tibial plateau may occur without any PCL deficiency, since,in external rotation, the PCL is relaxed and will allow a certain amount of posterior displacement

of the tibial plateau. However, where the PCL is torn, the pivot shift will be very much more

pronounced.

(c) Increased external rotationIt is indicative of lateral lesions. The test is performed as a side-to-side comparison:-

External rotation in 20 flexion: The examiner stands at the foot of the couch, and looks for

unequal rotation. The difference found may be expressed in degrees (Fig. 40).


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Figure 40

External rotation in 90 flexion.

(d) Lateral hypermobilityThis test has been described by Gilles Bousquet. It is performed with the knee flexed at 90, withthe examiner's hands around the top of the tibia (tibial tubercle), applying external rotation (Fig.41). A positive test shows that the posterolateral structures have been injured.

To complete the test, the examiner should

Look for stiffness of the hamstrings,. With the hip flexed at 90, the popliteal angle is measured

(Fig. 42). The examiner tries to take the knee into extension, maintaining the foot in dorsiflexion.

Figure 41 Figure 42

Look for stiffness of the rectus femoris. For this, the patient is positioned prone. The heel isbrought towards the buttock, with the hip in extension. The heel-to-buttock distance is measured


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(Fig. 43). While the patient is supine, a check should also be made for popliteal (Baker's) cysts.

This test should always form part of the general examination of a knee patient; in particular, itmust always be borne in mind that knee pain may be due to problems in the hip or the spine.

Figure 43

3 - FURTHER INVESTIGATIONS

The following techniques are available for the further workup of knee patients:

1 - Scout radiographs

A.p. single-leg stance; lateral in 30 of flexion; axial views in 30 of flexion.

Instability should be investigated using the radiological Lachman test. For the instrumented test,

a Telos device may be used (varus, medial/lateral instability, a.p. instability).

Long films may be used to measure limb length and study the axes of the lower limb.

Rosenberg views (p.a. weight-bearing views in flexion) may be used to detect incipient OA or to

screen for osteochondritis dissecans of the medial femoral condyle.

2 - Other imaging techniques

Arthrography: This is a useful technique in peripheral meniscal detachment, or when there is

a suspicion of recurrent meniscal lesions.

CT is essential in cases of patellar instability and of bone disease (tumour, trauma).


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MRI shows meniscal lesions, injuries of the cruciates, villonodular synovitis, and necrosis of

the femoral condyles.

Radionuclide bone scans should be requested if it is thought that the patient may be suffering

from a tumour, from incipient avascular necrosis of a femoral condyle, or from reflex

sympathetic dystrophy; or if an infection is suspected.

3 - Blood tests

Sed rate, blood count, CRP, and rheumatological tests (latex fixation, Rose-Waaler, complement,

ANA, antimitochondrial antibodies, Lyme serology, etc.) should be ordered in inflammatoryknee conditions.

5 - Arthroscopy and biopsy

These modalities are rarely indicated in the diagnostic workup of knee patients. They may

occasionally be used in inflammatory conditions.

The various signs observed may be grouped together to distinguish a number of knee disorderpatterns:-

- Complete isolated anterior instability = Lachman-Trillat +; pivot shift +

- Incomplete isolated anterior instability = Lachman-Trillat: Delayed firm endpoint +; glide

pivot shift +

- Advanced anterior instability = Lachman-Trillat +; pivot shift +, straight anterior drawer +

- Posterior instability = Lachman-Trillat: Delayed firm endpoint +; posterior drawer +, tibial

sag +, pivot shift 0

- Organic patellar instability = Apprehension +

- Anterior knee pain syndrome = Medial facet tenderness + (quad/hamstring stiffness )

- Medial meniscus lesions = Effusion +, medial joint line tenderness +, McMurray +, Grinding

+

- Lateral meniscus lesions = Effusion +, lateral joint line tenderness +, Grinding +, Cabot +

- Isolated peripheral lesions:Medial collateral ligament = Instability in valgus-flexion-external rotation

- Associated peripheral lesions:Medial triad (ACL + MCL + IM )


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Lachman-Trillat +, direct anterior drawer +, valgus-flexion-external rotation +,

instability in extension-valgus +

- Posterolateral lesions: Posterior drawer +, reverse pivot shift +

- Pentads:Posterior drawer +, straight anterior drawer +, Lachman-Trillat +, pivot shift +, external rotation

recurvatum +(in lateral pentad);

Medial instability in extension, valgus-flexion-external rotation, varus-flexion-internal rotation +

(in medial pentad)

PS: The authors would appreciate hearing from other colleagues, in order toexpand and augment the present list of tests. Please send your suggestions,

descriptions of tests, etc. toProf. Philippe Neyret

Centre Livet8, rue de Margnolles

F-69300 CaluireFrance

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