Comprehensive Guide to Clinical Medicine

Musculo-Skeletal Examination

Detailed examination of the joints is usually not included in the routine medical examination. However, joint related complaints are rather common, and understanding anatomy and physiology of both normal function and pathologic conditions is critically important when evaluating the symptomatic patient. By gaining an appreciation for the basic structures and functioning of the joint, you'll be able to "logic" your way thru the exam, even if you can't remember the eponym attached to each specific test!

I have included detailed descriptions of the shoulder, knee, and low back examinations as these are the most commonly affected areas. In addition, a review of relevant anatomy, function, and common disorders are described for most of the other major joints. This is not meant to be an all-inclusive list.

A few general comments about the musculoskeletal exam

Historical clues when evaluating any joint related complaint:

What is the functional limitation?
Symptoms within a single region or affecting multiple joints?
Acute or slowly progressive?
If injury, what was the mechanism?
Prior problems with the affected area?
Systemic symptoms?

Common approach to the examination of all joints:

Make sure the area is well exposed - no shirts, pants, etc covering either side - gowns come in handy
Carefully inspect the joint(s) in question. Are there signs of inflammation or injury (swelling, redness, warmth)? Deformity? As many joints are symmetric, compare with the opposite side
Must understand normal functional anatomy - what does this joint normally do?
Observe the joint while patient attempts to perform normal activity - what can't they do? What specifically limits them? Was there a discrete event (e.g. trauma) that caused this? If so, what was the mechanism of injury?
Palpate the joint in question. Is there warmth? Point tenderness? If so, over what anatomic strucutres?
Assess the range of motion, both active (patient moves it) and passive (you move it) if active is limited/causes pain.
Strength, neuro-vascular assessment.
Specific provocative maneuvers related to pathology occurring in that joint (see descriptions under each joint).
In the setting of acute injury and pain, it's often very difficult to assess a joint as patient "protects" the affected area, limiting movement and thus your examination. It helps to examine the unaffected side first (gain patient's confidence, develop sense of their normal).

The Knee Exam

Observation:

Make sure that both knees are fully exposed. The patient should be in either a gown or shorts. Rolled up pant legs do not provide good exposure!
Watch the patient walk. Do they limp or appear to be in pain? When standing, is there evidence of bowing (varus) or knock-kneed (valgus) deformity? There is a predilection for degenerative joint disease to affect the medical aspect of the knee, a common cause of bowing.

Varus Knee Deformity, more marked on the left leg.

Make note of any scars or asymmetry. Chronic/progressive damage, as in degenerative joint disease, may lead to abnormal contours and appearance. Is there obvious swelling as would occur in an effusion? Redness suggesting inflammation?

Is there evidence of atrophy of the quadriceps, hamstring, or calf muscle groups? Knee problems/pain can limit the use of the affected leg, leading to wasting of the muscles.

While both legs have well developed musculature,
the left calf and hamstring are bulkier than the right.

Look at the external anatomy, noting structures above and below the knee itself:

Patella
Patellar tendon
Quadriceps/Hamstring/Calf muscles
Medial and lateral joint lines.
Femur and Tibia
Tibial tuberosity

University of Washinton, Ananatomy of Knee 1
University of Washinton, Ananatomy of Knee 2
University of Washinton, Ananatomy of Knee 3

Palpation and Examination for Degenerative Joint Disease:

If the knee is injured, start by examining the unaffected side. This allows for comparison and relaxes the patient as you are not performing maneuvers that cause discomfort from the outset.
Ask the patient to bend the knee, gauging whether they can fully extend and flex. This is referred to as their active range of motion. Full extension is 0 degrees, full flexion ~ 140.

Knee Flexion (Left) and Extension (Right)

Place one hand on the patella. Note any warmth, which if present, would suggest inflammation. Grasp the ankle or calf with your other hand and gently flex the knee. Note the extent to which you can flex and extend the knee, referred to as its passive range of motion. Also, using the hand on the patella, feel for crepitus. This is a crackling/grinding sensation that occurs with movement. If present, it's suggestive, but not diagnostic, of degenerative joint disease (DJD). It reflects a loss of the normal smooth movement between the articulating structures (femur, tibia, and patella). DJD is suggested by the presence of pain with activity that gets progressively more limiting over time. There may be a history of antecedent injury, which caused the inciting damage to the articulating surface. And co-existent damage to ligaments or menisci may also be present (see below). When defining the extent of DJD, the knee is broken into 3 compartments: Medial, central, and lateral. DJD can occur in any or all regions. The precise location of the DJD can be hard to determine on examination and is more accurately defined via x-rays.

X-Ray of Normal Knee (Left) and Knee With DJD (Right)

If any of the above maneuvers elicits pain, stop and note at what point in the range of motion this occurs.
It's important to note that many patients report noises (e.g., creaking, popping, cracking) associated with joint movement. The vast majority of these sounds are not clinically significant. Rather, pain or functional limitation are the subjective complaints which carry clinical relevance.

Tests for an effusion:

An effusion is the accumulation of fluid within the joint space. If there is a large collection, the knee will look swollen. Lesser amounts of fluid can be a bit more subtle. Patient's symptoms are often related to whatever caused the fluid to accumulate in the first place. The effusion itself makes the knee feel as if it's somewhat unstable or floating and may limit range of motion. Effusions resulting from inflammatory arthritis (e.g. infection, gout, rheumatoid arthritis) are associated with other signs of inflammation, including: warmth, redness, pain with any movement.

Large Effusion, Right Knee.

Ballotment (helpful if the effusion is large)

Slightly flex the knee which is to be examined.
Place one hand on the supra-pateallar pouch, which is above the patella and communicates with the joint space. Gently push down and towards the patella, forcing any fluid to accumulate in the central part of the joint.
Gently push down on the patella with your thumb.
If there is a sizable effusion, the patella will feel as if it's floating and "bounce" back up when pushed down.

Balloting the Left Knee.

Milking (helpful for detecting small effusions)

Gently stroke upwards along the medial aspect of the patella, pushing fluid towards the top and lateral aspects of the joint.
Gently push on the lateral aspect of the joint. If there's a small effusion, the fluid which was milked to the lateral aspect will be pushed back towards the medial area of the joint, causing the medial skin to bulge out slightly.

Video demonstrating technique for milking an effusion.

Inflammatory Arthritis and Effusions:

Intense inflammatory processes within the joint space can also cause an effusion. Infection, gout, and rheumatoid arthritis are a few of the conditions that can lead to an inflammatory arthritis (IA) and effusion. The joint and overlying skin is usually warm and red. In addition, there is significant pain with any active or passive movement. The more intense the inflammation, the more severe the pain and the more limited the range of motion. Identifying the precise cause of IA is critical as it directs the clinician towards the best treatment, limiting permanent damage to the joint. This usually requires aspiration and examination of the joint fluid. Inflammatory fluid has a high white cell count and should contain other clues as to its origin (e.g. gout --> crystals on microscopy; infection --> bacteria on gram stain and culture; etc). Fluid from those with degenerative effusions has relatively few white cells. Clinically, patients with DJD have few signs of inflammation and some degree of preserved range of motion (ROM). Historical information also helps distinguish DJD from IA. DJD is usually slowly progressive while those with IA more often have an acute presentation. Additionally, those with IA may have characteristic patterns of recurrence (e.g. great toe MTP in gout, MCPs of hands in RA), systemic symptoms, suggestive joint deformities (e.g. ulnar deviation of the hands in RA), and particular radiographic changes. Of course, it's possible to have element of both IA and DJD. DJD, for example, can result from joint damage that occurred secondary to past episodes of gout or infection.

Gouty Inflammation of Metatarsal-Phalangeal Joint, Left Great Toe

Specific Maneuvers for the Knee Exam

Tests for Meniscal Injury

Normal anatomy and function: The menisci sit on top of the tibia and provide a cushioned articulating surface between the femur and tibia. Symptoms occur when a torn piece interrupts normal smooth movement of the joint. This can cause a sensation of pain, instability ("giving out") or locking in position. Injury may also cause swelling. If the meniscus has been injured and no longer adequately covers the tibia, damage can occur to the underlying bone, leading to degenerative arthritis.

Anatomy of Menisci, Right Knee (patella has been removed).

Joint Line Tenderness:

Have the patient slightly flex their knee. The knee is slightly flexed when performing all of the functional tests that are described below. This positions the joint such that other stabilizing elements do not interfere with the structure that is being tested.
Define the joint space along its lateral and medial margins. The joint line is perpendicular to the long axis of the tibia.
Gently palpate along first the medial and then the lateral margins. Pain suggests that the underlying meniscus is damaged. Osteoarthritis can also cause joint line tenderness

Palpation Along Lateral (picture on left) and Medial (picture on right) Joint Lines. The Joint Line is Marked by Purple Line.

Note that only a portion of the meniscus lies near the joint line. The remainder of the meniscus cannot be assessed with this technique.

	Video Demonstrating Assessment of Medial Joint Line Tenderness.
	Video Demonstratinag Assessment of Lateral Joint Line Tenderness..

McMurray's Test

When examining the right knee, place your left hand so that your middle, index, and ring fingers are aligned along the medial joint line.
Grasp the foot with your right hand and fully flex the knee.
Gently turn the ankle so that the foot is pointed outward (everted). Then direct the knee so that it is pointed outward as well (valgus stress).
While holding the foot in this everted position, gently extend and flex the knee. If there is medial meniscal injury, you will feel a "click" with the hand on the knee as it is extended. This may also elicit pain.

Simulated McMurray's Test With Foot Everted (picture on left). Close-up (picture on right) Reveals How This Maneuver Streeses The Medial Meniscus.

McMurray's Test: Assessment Of Medial Meniscus Demonstrated In Picture On Left, Lateral Meniscus In Picture On Right.

Now, return the knee to the fully flexed position, and turn the foot inwards (inversion). Then direct the knee so that it is pointed inward as well (varus stress).
Place the index, middle, and ring fingers of your left hand along the lateral joint line.
Gently extend and flex the knee. If the lateral meniscus has been injured, you may feel a "click" with the hand palpating the joint line. You may also elicit pain.

Video showing McMurray's Test.

Appley Grind Test

Have the patient lie on their stomach.
Grasp one ankle and foot with both of your hands and gently flex the knee to ninety degrees. Hold the patients leg down by gently placing your leg over the back of their thigh.

Appley Grind Test

Push down gently while rotating the ankle back and forth.
This maneuver places direct pressure on the menisci. If injured, it will cause pain.
Test the opposite leg in the same fashion.

Tests for Injury to the Ligaments

Normal anatomy and function

The ligaments are very strong tissues that connect bone to bone. In the knee, they assure stability and correct alignment. There are 4 main ligaments in the knee: Medial collateral (MCL), lateral collateral (LCL), anterior cruciate (ACL) and posterior cruciate (PCL). The medial and lateral ligaments provide stability in response to medial and lateral joint stress. The cruciate ligaments limit anterior and posterior movement of the femur on the tibia and limit the degree to which the knee can rotate. Injury usually requires significant force. Following a ligamentous injury, there is generally acute pain, swelling and the injured person will often report hearing a "pop" (the sound of the ligament tearing). After the acute swelling and pain have dissipated, the patient may report pain and instability (sensation of the knee giving out) during any maneuver that would expose the deficiency created by the damaged ligament (e.g. rotation, during which there is nothing to "check" the movement of the femur on the tibia).

Anatomy of Ligaments, Right Knee (Patella Has Been Removed).

The following are common mechanisms of injury for each of the major ligaments:

ACL: Most commonly injured when the foot is planted while extreme rotational force is applied (e.g. a cleated foot caught in the turf while an athlete attempts to rotate towards that side). The ACL may also be injured from a direct force on the lateral knee while the foot is planted.
PCL: Much less commonly injured then the ACL. Posterior force on the tibia (e.g. the tibia striking against the dashboard in a motor vehicle accident) can lead to disruption.
LCL: Direct force on the medial aspect of the knee while the foot is planted.
MCL: Direct force on the lateral aspect of the knee while the foot is planted.

Given the forces required to tear a ligament, menisci are often damaged at the same time. It is also possible to tear more then one ligament at once. When testing any ligament, remember the following:

Always begin your exam with the asymptomatic knee. This gives you some sense of the individual normal degree of laxity. That is, the "tightness" of everyone's ligaments varies somewhat. By working on their unaffected side, you will define "normal." It also helps to generate a sense of trust between you and the patient.
If you're unsure as to whether there is really an abnormality, check back and forth between the normal and abnormal sides. This will enhance your ability to identify differences.
It can be difficult to examine patients with large joints, particularly if you have small hands!
Detecting subtle abnormalities takes lots of practice, particularly if you don't have a great sense for the range of normal.
It can be extremely difficult to examine the acutely injured knee. Movement often causes significant pain. The patient is understandably apprehensive and will use surrounding muscles to prevent movement. This inability to relax is a normal response and may limit the extent of your exam. It may be necessary to simply wait until the acute inflammation resolves (with rest, elevation, anti-inflammatory medications, and time) before being able to perform an accurate exam.

Specifics of Ligament Testing

Medial Collateral Ligament

Slightly flex the right knee (~30 degrees).
Place your left hand along the lateral aspect of the knee.
Place your right hand on the ankle or calf.
Push steadily inward with your left hand while supplying an opposite force with the right.

Stressing the MCL

If the MCL is completely torn, the joint will "open up" along the medial aspect.

Simmulated Torn MCL--Note How Joint Line Opens Up Along Medial Aspect

Reverse hand position to assess the left knee.
Additionally, palpation along the course of the ligament may also elicit pain if it has been injured.

Video Demonstrating Medial Collateral Ligament Testing.

Lateral Collateral Ligament

Slightly flex the right knee (~30 degrees).
Place your right hand along the medial aspect of the knee.
Place your left hand on the ankle or calf.
Push steadily outward with your right hand while supplying an opposite force with the left.

Stressing the LCL

If the LCL is completely torn, the joint will "open up" along the lateral aspect.

Simmulated Torn LCL--Note How Joint Line Opens Up Along Lateral Aspect

Reverse hand position to assess the left knee.
Additionally, palpation along the course of the ligament may also elicit pain if it has been injured.

Video Demonstrating Lateral Collateral Ligament Testing.

Alternative method for stressing the medial lateral collateral ligaments:

Extend the patient's knee and cradle the heel between your arm and body. The knee should be slightly flexed.
Place your index fingers across the medial and lateral joint lines.
Using your body and index fingers, gently provide first medial and then lateral stress to the joint.

Stressing the MCL and LCL

Video demonstrating technique stressing the MCL and LCL.

Anterior Cruciate Ligament

Lachman's Test

For testing the right leg, grasp the femur just above the knee with your left hand and the tibia with your right.
Flex the knee slightly.
Pull up sharply (towards your belly button) with your right hand while stabilizing the femur with the left. The intact ACL will limit the amount of distraction that you can achieve. The intact ACL is described as providing a firm end point during Lachman testing.

Stressing the ACL

If the ACL is completely torn, the tibia will feel unrestrained in the degree to which it can move forward (see above for image of simulated ACL tear).
Compare this to the other leg, reversing your hand position.
The patient must be able to relax their leg for this test to work. If they cant, then compensatory muscles will limit the degree of motion, making it very difficult to assess the integrity of the ACL.
If the thigh is too big in circumference (or your hand too small) to stabilize, you can perform the Lachman's test with the leg hanging off the side of the table (see picture below). It may also help to further stabilize the leg by holding their ankle between your legs.

Variation On Lachman's Test For Patients With Large Legs.

Video Demonstrating Lachman's Test.

Video Demonstrating Positive Lachman's Test.

Anterior Drawer Test (Note: This test has largely fallen out of favor. It is included for the sake of completeness).

Have the patient lie down, with the right knee flexed such that their foot is flat on the table.
Gently sit on the foot. Grasp below the knee with both hands, with your thumbs meeting along the front of the tibia.
Gently pull forward, gauging how much the tibia moves forward in relation to the femur. The ACL, if intact, will provide a discrete end point.

Stressing the ACL

If the ACL is completely torn, the tibia will feel unrestrained in the degree to which it can move forward.

Simmulated Torn ACL--Note How Far The Tibia Is Distracted Relative To The Femur

Compare this to the other side by simply shifting your hands to the same position on the opposite leg and repeating.

Video Demonstrating Anterior Drawer Test.

Video Demonstrating Positive Anterior Drawer Test.

Posterior Cruciate (PCL)

Posterior Drawer Test

Have the patient lie down, the right knee flexed to 90 degrees, foot flat on the table.
Gently sit on the foot. Grasp below the knee with both hands, with your thumbs meeting along the front of the tibia.
Gently push backward, gauging how much the tibia moves in that direction in relation to the femur. The intact PCL will give a discrete end point.

Stressing the PCL (Because Of Its Posterior Location, The Actual Ligament Cannot Be Seen In Picture On Right)

Compare this to the other side by simply shifting your hands to the same position on the opposite leg and repeating.
If the PCL is completely torn, the tibia will feel unrestrained in the degree to which it moves backwards.

Simmulated Torn PCL--Note How Far Back The Tibia Moves Relative To The Femur

If the PCL is completely torn, the tibia may appear to "sag" backwards even before you apply any force.

Video Demonstrating Posterior Drawer Test.

Assorted Other Testing

Patello-Femoral Syndrome: A problem with the way in which the patellar articulates with the femur and moves (tracks) during flexion and extension. As a result, cartilage lining the undersurface of the patella becomes irritated and worn down. Known as Chondromalacia, this process causes anterior knee pain with activity and often after prolonged sitting. Several ways of assessing for this condition are described below:

Have the patient slightly flex the leg to be tested.
Gently push down on the patella with both thumbs, which may elicit pain in the setting of Chondromalacia.
Now, gently move the patella from side to side and try to palpate its undersurface. This may elicit pain in the setting of Chondromalacia.
Hold the patella in place with your hand and ask the patient to contract their quadriceps muscle. This will force the inferior surface of the patella onto the femur, eliciting pain in the setting of Chondromalacia.

Assessing For Chondromalacia

Bursitis

Bursa are small pouches of fluid that lie between bony prominences and the tendons that surround joints. Their presence allows the tendons to move without generating a lot of friction. The bursa do not communicate with the joint space itself. Inflammation of the bursa, most commonly due to overuse of the tendon or direct trauma, can cause pain and swelling. Examination of the affected area reveals focal pain. Swelling, warmth, and redness may be prominent if there is concurrent infection, another cause of bursitis. Bursitis can be distinguished from an intra-articular process because of the location of the pain and the fact that movement of the joint itself does not cause discomfort. The major bursa surrounding the knee include:

Pre-patella: Located directly on top of the patella. Most frequently affected due to direct trauma, as may occur with people who spend a lot of time on their knees (e.g. carpet layers, carepenters).
Infrapatella (a.k.a. anserine): Below the knee. Also affected by direct trauma, as with the prepatella bursa.