Knee Exam Flashcards
What are the stages involved in this examination?
- INTRODUCTION
- INSPECTION OF BOTH KNEES (PATIENT STANDING)
- EXAMINE FOR EFFUSION WITH PATIENT LYING COMFORTABLY AND LEGS FULLY EXTENDED
- PALPATION OF THE KNEE JOINT
- ACTIVE and PASSIVE MOVEMENT OF THE KNEE JOINT
- EXAMINATION FOR STABILITY
- FOR COMPLETENESS
- CONCLUSION
The standard examination includes inspection, palpation, percussion and auscultation format. The same applies to the examination of a joint, albeit in an adapted form, what is this format?
LOOK, FEEL, MOVE + SPECIAL TESTS
So when examining a joint one inspects for deformity, skin changes, muscle wasting, etc. then feels for temperature, tenderness, deformity, etc. and, finally, one moves the joint to assess both the range of normal movements and also to check for stability e.g. test cruciate ligaments.
What is important to remember in an OSCE situation?
During an OSCE, listen to your examiner’s instructions and tailor your positive and negative findings accordingly. In exam conditions, you might be asked to examine only one knee – in that situation, it is acceptable to carry out a full examination on one side only, before offering to assess the contralateral joint for completeness.
BE ABLE TO EXAMINE BOTH JOINTS AND ALWAYS START WITH THE NON-AFFECTED SIDE!
Where does Knee pain usually come from?
Knee pain is often referred from pathology in the hip joint or even the spine. Arthritides (pleural of arthritis) more often than not affect more than one joint.
What is included in the introduction?
A. Wash hands with water or alcohol gel
B. Introduce self
C. Confirm patient’s name and date of birth
D. Explain procedure and seek informed verbal consent to examine the
knees
E. Ensure patient is comfortable and pain-free
F. Fully expose the patient’s legs. It is important to be able to inspect
quadriceps but allow the patient to maintain their modesty
- As ever before examining a patient (or even introducing yourself) you must wash your hands to prevent transmitting infection from one patient to another.
- Introduce yourself and check their identity to ensure they are the correct patient. Once you have gained verbal consent to examine their knees, ensure they are comfortable and their knees are exposed.
- Ask the patient if they are experiencing any knee pain – if yes, start with the pain-free knee and be very careful when examining the affected side.
- You must be able to see the entire knee and the quadriceps muscle mass. In clinical practice, this will often mean asking the patient to remove their trousers but please remember to maintain their modesty! Examine the knees with the patient standing and lying down.
- The order in which you carry out the examination will depend on the clinical setting. For instance, if the patient walks into a clinic, it is perfect acceptable to assess their gait first, and then carry out the part of the examination that requires them to stand. Conversely, if you’re seeing the patient on the ward, you can assess gait and alignment when standing last.
- This protocol standardizes the steps of the examination, but the order is adaptable to the clinical situation.
What is included in the inspection of both knees??
INSPECTION OF BOTH KNEES (PATIENT STANDING)
A. Look for any mal-alignment of the legs
B. Look for any wasting of the quadriceps muscle bulk
C. Look for any swelling, redness, deformity or scars of the knee
D. Remember to check the back as well as the front of the knees
- Before proceeding to inspect the patient, look around the bedside for any clues such as orthoses and walking aids.
- Alignment is only truly assessed while standing and weight-bearing.
- Remember to inspect the patient from the front, side and back.
A. Look for bow legs (genu varum) and knock knees (genu valgum).
Look for an abnormal unilateral deviation of the tibia either towards or away from the midline in the coronal plane. An abnormal medial deviation may result from arthritis of the medial side of the knee and an abnormal lateral deviation from arthritis of the lateral side of the knee.
B. Look for any wasting of the quadriceps muscle bulk – this muscle is the best place to look for muscle wasting as it is quick to atrophy and even relatively small changes are fairly easily noted due to its large size.
C. Look for any swelling, redness, deformity or scars of the knee - swelling or redness which may indicate inflammation. Scars may indicate previous trauma or surgery – make sure you inspect thoroughly, as arthroscopy scars can be very small.
D. Remember to check the back of the knees – possible pathology affecting the back of the knee includes a Baker’s cyst or a popliteal artery aneurysm.
What is included in the examination for effusion?
EXAMINE FOR EFFUSION WITH PATIENT LYING COMFORTABLY AND LEGS FULLY EXTENDED.
A. Feel for any warmth or skin tenderness over the knee
- Warmth of the knee is best felt with the back of the hand. At this point you may elicit skin tenderness which may be due to joint inflammation (or simply cellulitis which happens to be over the knee).
B. With the knee extended use your left hand to empty any fluid out of the suprapatellar bursa into the knee
- The synovial cavity of the knee lies in continuity with the often large suprapatellar bursa. Therefore effusions of the knee may be ‘masked’ by fluid ‘hiding’ in this bursa. Place your left hand on the patient’s mid- thigh and run it downwards towards the patella so as to empty any fluid within it into the knee.
C. Keep your hand over the suprapatellar bursa to maintain pressure and prevent it refilling
- Keep your hand in position just above the patella to prevent the bursa from refilling. The patella is normally in contact with the femoral condyles. However if there is a significant effusion and the knee is in extension then the pressure of the excess fluid may lift the patella off
the femoral condyles.
D. Attempt to ‘tap’ the patella against the femoral condyles with your right hand
- If this is the case then the patella may be pressed down against the femoral condyles causing a palpable (and occasionally audible) tap.
E. If patellar tap negative, smaller effusions can be demonstrated by cross-fluctuation
- Cross fluctuation (or sweep/ripple test): with one of your hands, firmly stroke along the medial side of the knee joint, distal to proximal – this should shift synovial fluid. Quickly repeat along the lateral side of the knee, proximal to distal – if the fluid bulges on the medial side, this is a positive test.
If the patient is not already seated, position them in a semi-recumbent position on the couch, so that they are comfortable.
What is included in the palpation of the knee joint?
PALPATION OF THE KNEE JOINT
A. With the knee in 90° flexion, palpate over the tibial tuberosity, patellar tendon, the margins of the patella, quadriceps tendon and the fibular head.
- A systematic approach should be used, one suggested method is to begin at the tibial tuberosity, then palpate the patellar tendon, moving to the margins of the patella. The quadriceps tendon should also be palpated (superior pole of the patella). This ensures that there is no palpable deficit in the extensor mechanism of the knee and no localised tenderness.
- The head of the fibula can be palpated as a protuberance on the lateral surface of the knee joint, just inferior to the lateral tibial condyle (when the knee is flexed).
B. Palpate for any tenderness in the joint margins
- The medial and lateral joint lines should be palpated – ideally in slight flexion – as this may elicit tenderness due to meniscal pathology. Do not forget to palpate behind the knee for any tenderness or swellings (i.e. Baker’s Cyst)
C. If quadriceps wasting is suspected measure the thigh circumference 10cm above the superior margin of the patella and compare with the opposite thigh
- It is important to measure at the same site on both thighs for consistent results.
What is included in the introduction?
What is included in the active and passive movement of the knee joint?
A. Active flexion and extension (‘please bring your heel to your buttock’, ‘please now straighten your leg back down’).
- With the patient supine, ask them to bring their heel to their buttock and then extend the leg back down to lie on the couch (normal range 0o – 140o). If there is a fixed flexion deformity of 15o and flexion is possible to 110o, then record the findings as a range of movement of 15o to 110o.
B. Ask patient to lift their leg with the knee kept straight
- Ask the patient to lift the leg with the knee kept straight – if the knee cannot be fully extended, then an extensor lag is present. This indicates quadriceps weakness or other abnormalities of the extensor apparatus.
C. Passive flexion and extension
- tell the patient that you are going to help with these movements and see if any more range of movement is possible. Feel for crepitus between the patella and femoral condyles, suggesting chondromalacia patellae (especially in young females) or osteoarthritis.
Normally, the knee can extend so that the femur and tibia are in longitudinal alignment. Record full extension as 0o. A restriction to full extension can occur with meniscal tears, osteoarthritis and inflammatory arthritis.
D. Assess for hyperextension
- lift both legs by the feet. Hyperextension (genu recurvatum) is present if the knee extends beyond the neutral position. Up to 10o is normal.
The object of the exercise is to assess the range of movement of knee joint to both active and passive movement. It is important to elicit a range of active movements first so that pain is not inflicted by over-zealous passive movements. Lie the bed flat at this point.
What is included in the examination for stability?
A. With the knee in extension, attempt to pull the tibia laterally (medial collateral ligament) then push it medially (lateral collateral ligament)
(If the collaterals are stable in extension, repeat the test with the knee flexed to 20-30o to assess for minor collateral laxity).
- To test the medial and lateral collateral ligaments
Hold the patients right leg between your right arm and trunk (a little below your armpit) use your right hand to stabilise the leg and prevent any rotation. Using your left hand push the knee medially whilst pulling laterally with your right hand and arm. This stresses the medial collateral ligament. Then pull the knee laterally and push the leg medially with your trunk to stress the lateral collateral ligament. To examine the left knee simply perform the opposite manoeuvres standing on the LEFT side of the couch.
- Abnormal movement suggests an extensive ligamentous rupture. If the knee is stable in complete extension, flex the knee to approximately 20-30o (to relax the posterior joint capsule) and repeat the movement. Abnormal laxity in this position suggests a partial or complete tear.
B. With the knee in 90° of flexion attempt to pull the tibia anteriorly (anterior cruciate ligament) then push it posteriorly (posterior cruciate ligament)
- To test the cruciate ligaments
Place the knee in 90° of flexion. Hold the foot in position on the couch by partially sitting on it (explain this to the patient and check if the patient has any pain in their foot first!). Firmly hold the upper tibia with both hands - fingers posterior and thumbs over the tibial tuberosity - and then push (POSTERIOR cruciate) and pull (ANTERIOR cruciate) on the leg to attempt to move the tibia with respect to the femur.
What is included in the for completeness?
To complete your examination you should also offer to compare with the contralateral joint and also offer to examine the hip above as this is often the cause of referred pain to the knee.
Offer to examine the ankle below.
You should also ask if the examiner would like you to assess the gait of the patient.
What pathologies may affect the back of the knees?
Baker’s cyst or a popliteal artery aneurysm.
What is Bakers Cyst?
A Baker’s cyst, also called a popliteal cyst, is a fluid-filled swelling that develops at the back of the knee.
Knee damage caused by a sports injury or a blow to the knee can lead to a Baker’s cyst developing
What is included in the conclusion?
CONCLUSION
A. Thank patient
B. Wash hands
C. Be prepared to orally summarise your findings
