Knee and Lower Leg

Proximal Tibia Fx

Plateau fractures or condylar, spine, tuberosity, subcondylar, epiphyseal

AP/LAT/Oblique

Proximal Fibula

Indicative of significant knee injury, also associated c medial malleolar fx. Common peroneal or anterior tibial art injury

TIB/FIB Shaft Fxs

Consider Compartment Syndrome

Long Leg Splint-2 slabs

Patella Fxs

Assoc c soft tissue disorders of knee

Jumpers Knee

Patella tendonitis

Bakers Cyst

Swelling behind knee, if ruptures, can get swelling of lower legs appears like a dvt. If sx of coincident arthritis of knee and thrombophlebitis of calf should have bakers cyst ruled out by arthrogram

Knee

Exam

Thorough history

Examine good leg first

Inspection-examine quads for atrophy

Palpation: for temperature, An effusion can be detected by noticing the loss of the peripatellar groove and by palpation of the fluid. Smaller effusions may be detected by compressing the medial and superior aspects of the knee, then pressing or tapping the lateral aspect to create a fluid wave. A perceptible bulge on the medial aspect suggests a small effusion; this sign may not be present with larger effusions. Ballottement of the patella may also be a useful technique for detecting an effusion. The examiner quickly pushes down on the patella. In the normal knee joint with minimal free fluid, the patella moves directly into the femoral condyle and there is no tapping sensation underneath the examiner’s fingertips. However, in the knee with excess fluid, the patella is “floating”; thus, ballottement causes the patella to tap against the femoral condyle. This sensation is transmitted to the examiner’s fingertips. Localized swelling over specific knee structures, such as the MCL or LCL, can also be noted. Crepitus, a palpable grating sensation, may be produced during certain motions in joints with cartilage disruption The maneuvers producing crepitus, the location of the crepitus, and any pain elicited should be recorded. Joint line tenderness can also be detected by palpating medial and lateral to the patella in the groove between the femoral condyle and the tibia.

Lachman-is typically performed while the patient lies supine with the knee flexed to 20° to 30° The examiner stands to the side of the patient’s leg with the patient’s heal on the examination table. The femur is grasped with one hand just above the knee. While the examiner grasps the femur firmly to prohibit motion of the upper leg and to relax the hamstrings, the other hand grasps the proximal tibia. The lower leg is then given a brisk forward tug and a discrete end point should be felt. A positive test is one in which the end point is not discrete or there is increased anterior translation of the tibia.

Finally, meniscal integrity is assessed using several specific examination maneuvers, including McMurray test, the Apley compression test, and the medial-lateral grind test (Figure 2). McMurray test is performed with the patient supine. The examiner stands on the side of the affected knee and places one hand on the heel and another along the medial aspect of the knee, providing a valgus force. The knee is extended from a fully flexed position while internally rotating the tibia. The test is repeated while externally rotating the tibia. A positive sign is indicated by a “popping” and sensation of symptoms along the joint line, often accompanied by an inability to fully extend the knee.

The Apley compression test is performed with the patient laying in a prone position on a low examination table. The examiner applies his/her knee into the posterior thigh of the leg to be examined, then flexes and externally rotates the tibia while gripping the ankle. The examiner then compresses the tibia downward. If this compression produces an increase in pain, the test is considered positive.

The medial-lateral grind test is performed with the patient supine on the examination table. The examiner cradles the affected leg’s calf in one hand and places the index finger and thumb of the opposite hand over the joint line. Valgus and varus stresses are applied to the tibia during flexion and extension. If a grinding sensation is palpated by the hand placed over the joint line, the medial-lateral grind test is deemed positive.

(JAMA 286:13 Oct 2001 JB24)

Medial Collateral Ligament Testing is done by applying valgus stress with the knee in full extension and then in 30 of flexion. If there is laxity in full extension, then there is a complete rupture of the MCL.

Ottawa Knee Rules

Age>55

Fibular Head Tenderness

Isolated Tenderness of Patella

Inability to flex 90 degrees

Inability to weight bear for four steps after injury and in the ED

Validated in children age 2-16 (Annals EM 42:1, 2003)

X-Rays

AP/LAT

Sunrise to better evaluate the patella

Tunnel view for the intercondylar notch for tibial spine fractures or loose foreign bodies

KNEEPlain radiographs of the knee usually include an AP and lateral view. With this two-view imaging protocol, the sensitivity of detecting knee fractures is only 79%. The addition of two oblique views for a four-view imaging protocol increases this sensitivity to 85% (22). To reduce the number of overlooked knee fractures, consider obtaining oblique plain radiographs and possibly even CT imaging for high-risk patients. The normal AP and lateral anatomy of the knee is shown in Figures 19 and 20.Figure 18. AP radiograph and diagram of normal right knee Figure 19. Lateral radiograph and diagram of normal right knee Using the DOH mnemonic again, a knee Dislocation is not a clinically or radiographically subtle diagnosis (Figure 20). The radiographic pitfall is not considering an associated popliteal artery injury. They occur in 23-60% of knee dislocations (23-25).Figure 20. Anterior dislocation of knee (Lateral view) There are three high-risk, Occult fractures of the knee. The first is a tibial plateau fracture, which alone accounts for one-third of all knee fractures. These fractures usually occur after a valgus force is applied with axial loading, such as when a pedestrian is struck by the bumper of a car. Because of the relative insensitivity of two-view plain radiographs, if a high-risk patient is unable to bear weight on the affected knee, two additional oblique views will help elucidate the injury. Figure 21 radiographically appears grossly normal on the two-view series but one can appreciate the impressive fracture pattern through the medial tibial plateau on one of the oblique views. CT imaging is necessary to evaluate the extent of any tibial plateau fracture and should be considered in the rare high-risk patient who has a normal four-view radiographic series. Such a high-risk patient might be a pedestrian struck in the knee by a car, has significant point-tenderness over the medial or lateral joint line, and is unable to bear any weight on the leg.Figure 21. Tibial plateau fracture of left knee (A) AP view, (B) Lateral view, (C) Oblique view, (D) Diagram

A B C D

The second Occult knee fracture is a Segond fracturea proximal lateral tibial avulsion fracture (Figure 22). The fractured piece was the insertion site of the lateral capsular ligament. Although the fracture piece appears clinically insignificant, be wary that Segond fractures have a significant concurrent risk for anterior cruciate ligament (ACL) tears. These patients should be discharged with a knee immobilizer and urgent follow-up with an orthopedist. Figure 22. Segond fracture of the left knee (AP view) For further images of a Segond fracture visit the EMedHome.com Archives for the clinical case discussing this injury.

And the third Occult fracture is a patella fracture, which comprises 40% of all knee fractures. It is usually the result of direct blunt trauma to the patella. Because of the overlapping femoral condyles, the AP view is poor in detecting patellar fractures. The best radiographic perspective is the lateral view. Figures 23 and 24 show the AP and lateral views of a patella fracture, respectively. Additional images such as the sunrise view, which is a tangential view of the patella with the knee flexed approximately 60 degrees, may be helpful especially in visualizing vertical patella fractures.Figure 23. Left transverse patella fracture (AP view) Figure 24. Left transverse patella fracture (Lateral view)

The primary Half pathology for the knee is a Maisonneuve fracture (Figures 25 and 26). In this injury, a fracture of the proximal fibula is associated with a fracture of the medial malleolus or deltoid ligament of the ankle. Often the ankle mortise is widened, and the tibiofibular syndesmosis is disrupted. Finding a proximal fibula fracture necessitates the need for an ankle exam and radiograph, and conversely finding a medial malleolus fracture and/ or widened mortise necessitates the need for a tibia-fibular exam and radiograph.Figure 25. Maisonneuve fracture: Right knee proximal fibula fracture (AP view of knee)

Figure 26. Maisonneuve fracture: Right ankle medial malleolus fracture (AP view of ankle)

The following proposed algorithm is a very reasonable approach (1): When the patient is first seen, if the peripheral circulation in the extremity is deficient, the dislocation should be reduced as quickly as possible and the circulatory status of the limb carefully re-assessed. Arteriography is routine for any patient having questionable circulation or absent peripheral pulses either before or after reduction of a dislocated knee. Arteriography should be done in an extremity that originally has no pulses, even though satisfactory pulses are restored after reduction, because intimal tears may be present even though the patency of the popliteal artery is sufficient for satisfactory circulation. An arteriogram is not routinely done when there is no sign of peripheral circulatory embarrassment before or after reduction. During the first 48 to 72 hours after injury, the extremity is closely monitored for an intimal tear that may progress and cause thrombosis. Selective arteriography is becoming the standard, as stated in a recent study: In the group of patients who present with knee dislocations and normal peripheral vascular examination arteriograms are not helpful. Most now recommend early ligament repair or reconstruction of the knee and aggressive rehabilitation, especially in young, active patients (1). References: (1) Canale: Campbell’s Operative Orthopaedics, Ninth Edition, Copyright 1998 Mosby, Inc. Selective arteriography is becoming the standard, as stated in a recent study: In the group of patients who present with knee dislocations and normal peripheral vascular examination arteriograms are not helpful. Most now recommend early ligament repair or reconstruction of the knee and aggressive rehabilitation, especially in young, active patients (1). References: (1) Canale: Campbell’s Operative Orthopaedics, Ninth Edition, Copyright 1998 Mosby, Inc. (2) Roberts DM Emergency department evaluation and treatment of knee and leg injuries Emerg Med Clin North Am 2000 Feb; 18: 67-84 (3) Martinez D, et. al. Popliteal artery injury associated with knee dislocations Am Surg 2001; 67:165-7

Osgood Schlatter

8-15 y/os

Pn/swelling at tibila tuberosity

Dislocation of the Knee

Box the peroneal nerve-get foot drop

Anterior disloc-popliteal injury

Posterior-can be reduced

Medial/Lat/Rotational-must go to OR

Patellar Dislocation-can be easily reduced, do patella apprehension test, push patella laterally, if pt reacts or tenses quad then positive

Ankle/Brachial pressure ratio less than 0.8 (using doppler) requires arteriography.

The presence of pulses and equal ankle-brachial indices is nearly 100% sensitive in excluding operative vascular injury (Am J EM, 2/07, pg. 241)

(Injury 2008;39:710)

Quadriceps Tendon Rupture

Can not do straight leg raise. Need surgical repair within 58-72 hours. Put in immobilizer

Osteoarthritis

Popliteal (Baker’s) Cyst

there is no way to differentiate it from DVT on clinical grounds, get an ultrasound.

if the cyst is ruptured and you give heparin, can get massive bleeding and even one case of posterior compartment syndrome

may see hemorrhagic ring surrounding ankle

you almost never will feel a mass

since the cyst contains inflammatory fluid, if it ruptures, entire calf will get red, swollen and painful. Knee pain which gets relieved but then the calf begins to hurt is classic

Differential: thrombophlebitis, baker’s cyst, muscle tear (gastroc), plantaris tendon rupture, cellulitis, fasciitis, compartment syndrome, popliteal aneurysm, ganglia, neural tumors, sarcoma, hemangioma

Shin Splints

Here are my tips re shin splints and exhaustion: 1) While you can usually acutely double your short duration exercise time, a marathon does not “scale” the same way for many, if not most people. Next time take your training up to 2/3rds of the marathon distance. 2) Shin splints and stitches usually come either early or late in a run. If early it is usually because you haven’t warmed up properly or are trying to increase the pace to fast. They also are almost universal in new runners or reconditioning ones. In both cases slowing down and running or walking through them is fine. When they occur late in the run they usually indicate an acute electrolyte disturbance. I had good results with continuous supplementation with magnesium (oxide) which most diets (including middle class Indian ones) are sorely deficient in and which is associated with atherosclerosis and SCD. Trying to maintain a fairly constant sodium in addition to hydration level is also important. Some runners with persistent problems report relief with Mg++ plus 400 IU q.d. vitamin E and at least 100 mg q.d. of CoQ10. If, as you say, you were completely drained and exhausted you may want to not only increase the length of your training runs (and take the supplements I list above), but also consider tanking up your muscle fuel reserves with p.o, creatine supplementation. I once employed a guy who was both a superb athlete and did consulting with big name athletes on nutrients. I can tell you that ALL world class athletes are stuffed full of legal performance enhancing nutrients and that these nutrients do make a positive difference. Creatine supplementation can have a dramatic effect on muscle mass and endurance and seems very safe (and also to reduce injury). While I realize you are not aspiring to be a professional athlete, I think that improving adaptation and tolerance for training through good nutrition (including judicious use of supplements) is both good sense and good for the body. It is interesting to note that superb athletes rarely live to anywhere near the maximum lifespan for humans. There are no great centenarian athletes, yet. One clue as to why this is the case is to look at the T-Bar levels and free radical adducts in the urine and serum of athletes after a good workout: they are astronomical — often higher than seen after 10 minutes of global systemic ischemia! Years before it was being considered as a marker of ischemia-reperfusion injury the cytochrome C levels of conditioned athletes after exercise were shown to be elevated. Runners also get a blast of Fenton reaction mediated radicals as a result of the release of free hemoglobin due to hemolysis (in part from foot impact on the pavement).

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