ࡱ> ` %bjbjss .%TTTTtThU X X X X XYtY<!!!!!!$hpE_c X X_c_cE X XZvvv_c X Xv_cvvR!Q XtU P*dT5sjKp03v<QQ'$Yr\v`^_sYYYEEv YYY_c_c_c_cD(-$&- COMMON INJURIES TO THE KNEE ACL INJURIES: Alan Horn, MD http://www.emedicine.com/radio/topic853.htm The anterior cruciate ligament (ACL) is the most commonly injured of the major knee ligaments. Injuries occur frequently in both athletes and nonathletes. The ACL is a vital ligamentous stabilizer of the knee that resists anterior translation and secondarily resists varus and valgus forces (Swenson, 1995). The ACL also functions as a mechanoreceptor that relays information about knee tension to the central nervous system. Patients with ACL injury have variable knee instability that may limit even ordinary daily activities. They report particular difficulty with cutting and pivoting. The torn ACL undergoes limited healing. Long-term morbidity is common with sequelae including articular cartilage injury, secondary meniscal tears, and osteoarthritis. Diagnosis ACL injury is usually diagnosed on the basis of the patient's history and physical findings or MRIs. Arthroscopy and arthrotomy are the criterion standards for diagnosis, but they are invasive and costly. The skilled clinician can diagnose as many as 90% of ACL tears by reviewing the history and physical findings (Johnson, 1993; Lee, 1998). Patients typically report an audible pop and giving way at the time of injury. A knee effusion usually develops over the next 24 hours. A tear is confirmed at physical examination primarily by the Lachman test (Swenson, 1995). The anterior drawer and pivot shift tests are often helpful, and arthrometric examination may be contributory. Role of MRI As described above, MRI may alter the treatment of patients by allowing confident diagnosis or exclusion of an ACL tear in patients with equivocal physical exams. However, the greatest contribution of MRI in ACL-injured patients is in the evaluation of coexisting internal derangements (Munk, 1998). Diagnosis or exclusion of these coexistent injuries often alters the treatment of patients Treatment Treatment of ACL tears ranges from conservative therapies to surgical ACL reconstruction. The patient's activity level (and expectations for activity in the future) is the most important factor guiding the choice of treatment (Swenson, 1995). Associated meniscal and ligamentous injuries, the degree of laxity, and the patient's age and willingness to pursue vigorous postoperative physical therapy are other major determinants. ACL-graft reconstruction stabilizes the ACL-deficient knee, increasing activity levels, and preventing reinjury resulting from repeated subluxation. However, ACL-reconstruction however has not yet been proven to prevent long-term osteoarthritic deterioration. (Swenson, 1995; Dye, 1998) It is generally believed that late ACL reconstruction decreases postprocedural stiffness and improves outcomes. Surgery is delayed until swelling has subsided and range of motion is restored (Swenson, 1995). Surgery Overview http://health.yahoo.com/ency/healthwise/hw28289 Surgery for  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" anterior cruciate ligament (ACL) injuries involves reconstructing or repairing the ACL. ACL reconstruction surgery uses a  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" graft to replace the ligament. The most common grafts are autografts using part of your own body, such as the tendon of the kneecap (patellar tendon) or one of the hamstring tendons. Other good choices include allograft tissue, which is donor material. In repair surgery, the ends of the torn ligament are sewn back together. Most ACL surgery is done by reconstructing the ACL because reconstruction gives better results than repair surgery. Repair surgery generally is only used when the ACL has been torn from the upper or lower leg bone. This type of injury is uncommon. In the case of an avulsion fracture, the bone fragment connected to the ACL is reattached to the bone. ACL surgery is done by making small incisions in the knee and inserting instruments for surgery through these incisions ( HYPERLINK "http://health.yahoo.com/ency/healthwise/hw198580/hw198583;_ylt=A9htfowoM0hE0h0BNQzogrMF" arthroscopic surgery) or by cutting a large incision in the knee (open surgery). Arthroscopic surgery Many health professional use arthroscopic surgery rather than open surgery for ACL injuries because: It is easy to see and work on the knee structures. It uses smaller incisions than open surgery. It can be done at the same time as diagnostic arthroscopy (using arthroscopy to determine the injury or damage to the knee). It may have fewer risks than open surgery. Rehabilitation is often faster after arthroscopy than after open surgery. Arthroscopic surgery is performed under  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" spinal or  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" general anesthesia. During arthroscopic ACL reconstruction, the surgeon makes several small incisionsusually two or threearound the knee. Sterile saline (salt) solution is pumped into the knee through one incision to expand it and to wash blood from the area. This allows the health professional to see the knee structures more clearly. The surgeon inserts an arthroscope into one of the other incisions. A camera at the end of the arthroscope transmits pictures from inside the knee to a TV monitor in the operating room. Surgical drills are inserted through other small incisions. The surgeon drills small holes into the upper and lower leg bones where these bones come close together at the knee joint. The holes form tunnels through which the graft will be anchored. The surgeon will take the autograft (replacement tissue) at this point. If it comes from the knee, it will include two small pieces of bone called "bone blocks" on both ends. One piece of bone is taken from the kneecap and the other piece is taken from a part of the lower leg bone near the knee joint. If the autograft comes from the hamstring, bone blocks are not taken. The graft may also be taken from a deceased donor (allograft). See an illustration of a  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" bone and tissue graft. The graft is pulled through the two tunnels that were drilled in the upper and lower leg bones. The surgeon secures the graft with screws or staples and will close the incisions with stitches or tape. A temporary surgical drain may be put in place. The knee is bandaged, and you are taken to the recovery room for 2 to 3 hours. During ACL surgery, the surgeon may repair other injured parts of the knee as well, such as  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" ligaments,  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" cartilage, or broken bones. What To Expect After Surgery Arthroscopic surgery is often done on a 1-day, outpatient basis. Other surgery may require staying in the hospital for a couple of days. To  HYPERLINK "http://health.yahoo.com/ency/healthwise/tc4128;_ylt=A9htfowoM0hE0h0BOwzogrMF" \l "tc4128-sec" care for your incision while it heals, you need to keep it clean and dry and watch for signs of infection. Physical rehabilitation after ACL surgery may take several months to a year. The length of time until you can return to normal activities or sports is different for every person; it may range from 6 to 12 weeks. Why It Is Done The goal of ACL surgery is to restore normal stability in the knee and the level of function you had before the knee injury, limit loss of function in the knee, and prevent injury or degeneration to other knee structures. Not all ACL tears require surgery. You and your health professional will decide whether rehabilitation only or surgery plus rehabilitation is right for you. You may choose to have surgery if you: Have completely torn your ACL or have a partial tear and your knee is very unstable. Have gone through a rehabilitation program and your knee is still unstable. Are very active in sports or have a job that requires knee strength and stability (such as construction work), and you want your knee to be as strong and stable as it was before your injury. Are willing to complete a long and rigorous rehabilitation program. Have  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw27231;_ylt=A9htfowoM0hE0h0BPAzogrMF" \l "hw27231-sec" chronic ACL deficiency that is affecting your quality of life. Have injured other parts of your knee, such as the  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" cartilage or  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" meniscus, or other  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" knee ligaments or  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" tendons. You may choose not to have surgery if you: Have a minor tear in your ACL (a tear that can heal with rest and rehabilitation). Are not very active in sports and your work does not require a stable knee. Are willing to stop doing activities that require a stable knee or stop doing them at the same level of intensity. You may choose to substitute other activities that don't require a stable knee. (In sports, these other activities can include cycling or swimming.) Can complete a rehabilitation program that stabilizes your knee and strengthens your leg muscles to reduce the chances that you will injure your knee again and are willing to live with a small amount of knee instability. Do not feel motivated to complete the long and rigorous rehabilitation program necessary after surgery. How Well It Works Between 80% and 90% of people who have ACL surgery have favorable results, with reduced pain, good knee function and stability, and a return to normal levels of activity.  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "uh1097#uh1097" 1 ACL repair is usually successful for an ACL that has torn away from the upper or lower leg bone (avulsion). Between 3% and 10% of people who have ACL surgery still have knee pain and instability and may need another surgery (revision ACL reconstruction).  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "uh1099#uh1099" 2 Revision ACL reconstruction is generally not as successful as the initial ACL reconstruction. Risks ACL reconstruction surgery is generally safe. Complications from surgery or that may arise during rehabilitation and recovery include: Problems related to the surgery itself. These are uncommon but may include: Numbness in the surgical scar area. Infection in the surgical incisions. Damage to structures, nerves, or blood vessels around and in the knee. Blood clots in the leg. The usual risks of anesthesia. Problems with the graft tendon (loosening, stretching, reinjury, or scar tissue). The screws that attach the graft to the leg bones may cause problems and require removal. Limited range of motion, usually at the extremes. For example, you may not be able to completely straighten or bend your leg as far as the other leg. This is uncommon, and sometimes manipulation under anesthesia can help. Rehabilitation usually attempts to restore a range of motion between 0 degrees (straight) and 130 degrees (bent or flexion). You may lack a few degrees at either end of the range of motion after surgery and rehabilitation. Grating of the kneecap (crepitus) as it moves against the lower end of the thighbone (femur), which may develop in people who did not have it before surgery. This may be painful and may limit your athletic performance. Rarely, the kneecap may be fractured while the graft is being taken during surgery or from a fall onto the knee soon after surgery. Pain or swelling during activities ranging from daily activities to strenuous sports. About 40% to 80% of people have some pain or swelling only when they play strenuous sports. The remaining people may have some pain or swelling with milder amounts of activity.  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "aa54334#aa54334" 3 A thorough rehabilitation program and a slow, gradual return to activities will reduce the likelihood of pain and swelling. Pain and swelling that persist may indicate a possible  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" cartilage or  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" meniscus injury that happened when the ACL was torn. Pain, when kneeling, at the site where the tendon graft was taken from the patellar tendon or at the site on the lower leg bone (tibia) where a hamstring or patellar tendon graft is attached. Repeat injury to the graft (just like the original ligament). Repeat surgery is more complicated and less successful than the first surgery. Rarely, chronic pain, tenderness, and swelling ( HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "#" reflex sympathetic dystrophy) after the injury is healed. What To Think About In an avulsion fracture, repair surgery is always performed as soon as possible. In reconstruction of a partial or complete tear of the ACL, the best time for surgery is not known. Surgery immediately after the injury has been associated with increased fibrous tissue leading to loss of motion (arthrofibrosis) after surgery.  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "ug2543#ug2543" 4 Some experts believe that surgery should be delayed until the swelling goes down, you can move your knee again, and you have regained any lost strength in the muscles in the front of your thigh (quadriceps).  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "ug2543#ug2543" 4 Many experts recommend starting exercises to increase range of motion and regain strength shortly after the injury. In adults, age is not a factor in surgery, although your overall health may be. Surgery may not be the best treatment for people with medical conditions that make surgery a greater risk. These people may choose nonsurgical treatment and try to change their activity level to protect their knee from further injury. Current research on the surgical treatment of ACL injuries includes different techniques and places to attach grafts; different types of screws; different types of grafts, such as tendon, muscle, or fascial grafts from your body (autograft); and grafts from a donor (allograft). Grafts made of synthetic materials, such as Gore-Tex or Stryker Dacron (prosthetic ligaments), are rarely used anymore. When choosing a graft, consider the following: The success of surgery may be more dependent on the surgeon's skill and preference than the type of graft used. Replacement tissue from the kneecap (patellar) tendon is one of the strongest grafts available to replace the ACL. A kneecap graft may result in pain when kneeling. A hamstring graft may result in some hamstring weakness. There is no difference in how the knee functions between a kneecap and hamstring graft. However, a kneecap graft is overall more stable in the long term. A recent study indicates that kneecap and hamstring grafts resulted in a similar level of knee function after 3 years.  HYPERLINK "http://health.yahoo.com/ency/healthwise/hw28289" \l "ug2571#ug2571" 5 A kneecap graft entails more rehabilitation considerations than a hamstring graft, such as increased pain and swelling that may limit exercises for the thigh muscles. References Citations Fu FH, et al. (2000). Current trends in anterior cruciate ligament reconstruction. American Journal of Sports Medicine, 28(1): 123130. Noyes FJ, Barber-Westin SD (2001). Revision anterior cruciate ligament reconstruction: Report of 11-year experience and results in 114 consecutive patients. AAOS Instructional Course Lectures, 50: 451461. Barber-Westin SD, et al. (1997). A rigorous comparison between the sexes of results and complications after anterior cruciate ligament reconstruction. American Journal of Sports Medicine, 25(4): 514-526. D'Amato MJ, Rach BR Jr (2003). Anterior cruciate ligament reconstruction in the adult section of Anterior cruciate ligament injuries. In JC DeLee, D Drez Jr, eds., Orthopaedic Sports Medicine, 2nd ed., vol. 2, pp. 20122067. Philadelphia: Saunders. Feller JA, Webster KE (2003). A randomized comparison of patellar tendon and hamstring tendon anterior cruciate ligament reconstruction. American Journal of Sports Medicine, 31(4): 564573. Credits Author Paul LehnertEditor Kathleen M. Ariss, MSAssociate Editor Lila HavensPrimary Medical Reviewer William M. Green, MD - Emergency MedicineSpecialist Medical Reviewer Freddie H. Fu, MD - Orthopedic SurgerySpecialist Medical Reviewer Ryan Ritchie, MS, PT - Physical TherapyLast Updated April 23, 2004 COLLATERAL LIGAMENT TEARS http://www.zimmer.com/ctl?op=global&action=1&id=8053&template=PC Causes Torn collateral ligaments usually occur during contact sports like football or hockey. A blow to the outside of the knee while the foot is planted can push the knee inward toward the opposite leg, tearing the MCL. A blow to the inside of the knee that forces the lower leg to bend out can damage the LCL. Symptoms You may experience pain, tenderness, swelling, and stiffness, followed by instability (the knee may give way and not support your body weight). If the torn ligament heals but is not strong enough to support the knee, you may experience chronic instability. Diagnosis As discussed in the Diagnosis section of Arthritis and other Joint Problems, a history and physical exam will help the doctor make the diagnosis. Your doctor will order x-rays to rule out bone damage and a stress x-ray, which takes a picture of your leg pushed slightly outwards, to confirm a collateral ligament tear. An MRI scan can make the diagnosis, too. Treatment The mainstay of treatment for most collateral ligament injuries is rest, ice, compression, and elevation (RICE). Resting the knee gives the ligament time to heal. Ice applied 2 or 3 times a day for 15 to 20 minutes may decrease pain and swelling. Compressing the knee with a bandage or brace can limit swelling, as can elevating the knee whenever possible. You'll also need to start a physical therapy program that includes exercises to restore range of motion and strengthen the thigh (quadriceps) muscle. Most collateral ligament tears heal well with RICE and exercise. However, if the collateral ligament is completely torn or is accompanied by other injuries (like damage to the ACL), surgery may be required. The surgeon makes an incision in the area of the torn portion of the ligament. A ligament that's been pulled away from a bone is then reattached with sutures or a special staple. Chronic instability may need surgical reconstruction, which involves tightening up the loose ligament or replacing it with a graft. Patellofemoral Pain Syndrome: A Review and Guidelines for Treatment MARK S. JUHN, D.O., University of Washington School of Medicine, Seattle, Washington  HYPERLINK "http://www.aafp.org/afp/991101ap/991101b.html"  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/arrow.gif" \* MERGEFORMATINET A patient information handout on patellofemoral pain syndrome, written by the author of this article, is provided on page 2019. Managing patellofemoral pain syndrome is a challenge, in part because of lack of consensus regarding its cause and treatment. Contributing factors include overuse and overload of the patellofemoral joint, biomechanical problems and muscular dysfunction. The initial treatment plan should include quadriceps strengthening and temporary activity modification. Additional exercises may be incorporated as dictated by the findings of the physical examination. Footwear should be closely evaluated for quality and fit, and the use of arch supports should be considered. (Am Fam Physician 1999;60:2012-22.) Patellofemoral pain syndrome can be defined as retropatellar or peripatellar pain resulting from physical and biochemical changes in the patellofemoral joint. It should be distinguished from chondromalacia, which is actual fraying and damage to the underlying patellar cartilage. Patients with patellofemoral pain syndrome have anterior knee pain that typically occurs with activity and often worsens when they are descending steps or hills. It can also be triggered by prolonged sitting. One or both knees can be affected. Consensus is lacking regarding the cause and treatment of the syndrome.1  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  The etiology of patellofemoral pain syndrome may be multifactorial. Causes include overuse/overload, biomechanical problems and muscular dysfunction.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  Pathophysiology and Etiology The patella articulates with the patellofemoral groove in the femur. Several forces act on the patella to provide stability and keep it tracking properly (Figure 1). A common misconception is that the patella only moves in an up-and-down direction. In fact, it also tilts and rotates, so there are various points of contact between the undersurface of the patella and the femur.2,3 Repetitive contact at any of these areas, sometimes combined with maltracking of the patella that is often not detectable by the naked eye, is the likely mechanism of patellofemoral pain syndrome. The result is the classic presentation of retropatellar and peripatellar pain. This pain should not be confused with pain that occurs directly on the patellar tendon (patellar tendonitis).  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/2012_f1.jpg" \* MERGEFORMATINET  FIGURE 1. Stabilizers of the patella on the right knee. Various forces are responsible for patellar movement. The iliotibial band (not shown) has some fibers that attach to the lateral aspect of the patella.Many theories have been proposed to explain the etiology of patellofemoral pain. These include biomechanical, muscular and overuse theories. In general, the literature and clinical experience suggest that the etiology of patellofemoral pain syndrome is multifactorial. Overuse and Overload Because bending the knee increases the pressure between the patella and its various points of contact with the femur, patellofemoral pain syndrome is often classified as an overuse injury.4-8 However, a more appropriate term may be "overload," because the syndrome can also affect inactive patients. Repeated weight-bearing impact may be a contributing factor, particularly in runners.3 Steps, hills and uneven surfaces tend to exacerbate patellofemoral pain. Once the syndrome has developed, even prolonged sitting can be painful ("movie-goer's sign") because of the extra pressure between the patella and the femur during knee flexion. Biomechanical Problems and Muscular Dysfunction No single biomechanical factor has been identified as a primary cause of patellofemoral pain,9,10 although many have been hypothesized. Some of the more popular theories are discussed in the following sections. Pes Planus (Pronation). The terms "flat feet" and "foot pronation" are often used interchangeably. Technically speaking, foot pronation is a combination of eversion, dorsiflexion and abduction of the foot. This condition often occurs in patients who lack a supportive medial arch (Figure 2). Foot pronation causes a compensatory internal rotation of the tibia or femur (femoral anteversion)11 that upsets the patellofemoral mechanism. This is the premise behind using arch supports or custom orthotics in patients with patellofemoral pain.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/2012_f2.jpg" \* MERGEFORMATINET  FIGURE 2. Pes planus, or flat foot (left), in a nonweight-bearing state. Loss of the medial arch with weight-bearing (right) causes the ankle to "roll" medially. To compensate, the femur or tibia rotates internally, increasing valgus and stressing the patellofemoral mechanism. Arch supports can help with this problem.Pes Cavus (High-Arched Foot, Supination). Compared with a normal foot, a high-arched foot provides less cushioning for the leg when it strikes the ground. This places more stress on the patellofemoral mechanism, particularly when a person is running.3 Proper footwear, such as running shoes with extra cushioning and an arch support, can be helpful. (It is preferable to purchase such footwear from a reputable athletic shoe store with knowledgeable staff.) Q Angle. Although some investigators believe that a "large" Q angle (Figure 3) is a predisposing factor for patellofemoral pain, others question this claim. One study12 found similar Q angles in symptomatic and nonsymptomatic patients. Another study6 compared the symptomatic and asymptomatic legs in 40 patients with unilateral symptoms and found similar Q angles in each leg. Furthermore, "normal" Q angles vary from 10 to 22 degrees,3 depending on the study, and measurements of the Q angle in the same patient vary from physician to physician.13 Therefore, the physician should be wary of placing too much emphasis on such biomechanical "variants," as this can lead patients to believe that nothing can be done about their pain.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/2012_f3.jpg" \* MERGEFORMATINET  FIGURE 2. Q angle. The relevance of this measurement in patients with patellofemoral pain syndrome has been questioned.Muscular Causes. The potential muscular causes of patellofemoral pain can be divided into "weakness" and "inflexibility" categories (Table 1).3,4,6,7,9-11,14-23 Weakness of the quadriceps muscles is the most often cited area of concern. However, each potential cause should be evaluated and addressed appropriately to help guide conservative care. Treatment A review of the literature yields few quality randomized, controlled trials on the treatment of patellofemoral pain syndrome.1,24 Prospective long-term follow-up studies provide the most useful data.8-10,25,26 Until long-term randomized, controlled clinical trials are conducted, the treatment of patellofemoral pain syndrome must be guided by the available literature and clinical experience. Exercises and Physical Therapy Exercises for patellofemoral pain are based on the muscular causes listed in Table 1.3,4,6,7,9-11,14-23 Quadriceps strengthening is most commonly recommended because the quadricep muscles play a significant role in patellar movement. Hip, hamstring, calf and iliotibial band stretching may also be important. The decision to incorporate these additional exercises depends on an accurate physical examination. (Exercises used in the treatment of patellofemoral pain are illustrated in a patient information handout that follows this article.) Dedicated patients can often manage physical therapy on their own, with 20 minutes per day being a reasonable expectation. Guidance from a physical therapist can be helpful, but patients need to adhere to the therapist's recommended home program and should not expect overnight success. Patients may not experience improvement of symptoms for six weeks or much longer, and the syndrome may recur. Good physician-therapist communication is important but unfortunately is lacking in many medical settings. The physician can improve communication by asking for regular, written updates from the therapist, similar to the reports expected from a subspecialist referral. Relative Rest Initially, knee activity should be reduced, at least relatively, because the theory that patellofemoral pain is an overuse/overload syndrome has merit.5-8 A patient with the movie-goer's sign can benefit from straightening the leg or walking periodically as needed. If the patient is a runner or engages in impact activity and insists on continuing some rigorous activity, swimming or another nonimpact aerobic activity is a reasonable recommendation. For example, the so-called "elliptical" nonimpact exercise machines at health clubs have become quite popular for providing nonimpact aerobic activity.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  The most commonly recommended exercise for the treatment of patellofemoral pain syndrome is quadriceps strengthening.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  Ice and Anti-Inflammatory Drugs Ice is the safest anti-inflammatory "medication," but its successful use requires discipline. Applying ice for 10 to 20 minutes after activity is reasonable. A common complaint is the inconvenience of holding an ice bag on the knee, but a simple elastic wrap solves this problem. A frozen gel pack, crushed ice in a plastic bag or a bag of frozen vegetables also work well. Patients with patellofemoral pain syndrome have not been conclusively shown to benefit from anti-inflammatory drugs (NSAIDs). Although the same statement can be made about many treatments for patellofemoral pain, the drawback of NSAIDs is that their potential side effects may be more significant than any adverse effects of ice application or rehabilitative exercises. However, considering the convenience of NSAID therapy, a judicious trial may be worthwhile. Knee Sleeves and Braces The use of knee sleeves and braces in patients with patellofemoral pain is controversial.1,5,27 Typically, knee braces have a C-shaped lateral buttress that keeps the patella from deviating too far laterally. However, the patellofemoral mechanism is not that simple, for the patella moves in several planes.2,3 Knee braces are probably best reserved for use in patients with lateral subluxation that can be seen with the naked eye and can be easily palpated. A simple elastic knee sleeve with a patellar cut-out may provide some benefit, although this remains unproved. The use of a knee brace or sleeve should not be considered a substitute for therapeutic exercises. Taping the Knee Taping the patella into a certain position to reduce friction may be helpful, although the results of studies have varied.18,28-32 A technique embraced by some physical therapists is known as "McConnell taping."31 Although this taping method is helpful in selected patients,28,31,32 the original study that claimed efficacy31 was severely limited by the lack of a control group. A prospective randomized study30 found that McConnell taping plus physical therapy was no better than physical therapy alone. Still, when performed correctly in selected patients, taping may offer short-term pain relief. Most physical therapists are trained in taping and can teach patients to tape themselves.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  TABLE 1 Muscular Etiologies of Patellofemoral Pain Syndrome and Their Pathophysiology  Etiology  Pathophysiology  Weakness of the quadriceps The "quads" include the vastus medialis, vastus medialis obliquus (VMO), vastus intermedius, vastus lateralis and rectus femoris. Weakness may adversely affect the patellofemoral mechanism. Quad-muscle strengthening is often recommended.3,4,7,9,10,14-17 Weakness of the medial quadiceps, specifically VMO dysplasia Weakness of the VMO allows the patella to track too far laterally. Although the role of the VMO is controversial,18-20 VMO strengthening is often recommended.6,7,11,15,16 However, the VMO is a difficult muscle to isolate,21 and most patients find general quadriceps strengthening easier to accomplish. Tight iliotibial bands A tight iliotibial band places excessive lateral force on the patella and can also externally rotate the tibia, upsetting the balance of the patellofemoral mechanism.22,23 This problem can lead to excessive lateral tracking of the patella. Tight hamstring muscles The hamstring muscles flex the knee. Tight hamstrings place more posterior force on the knee, causing pressure between the patella and femur to increase.7,15,16 Weakness or tightness of the hip muscles (adductors, abductors, external rotators) The VMO originates on the adductor magnus tendon. This is the anatomic basis for recommending adductor strengthening.11,14,16 Abductor (gluteus medius) strengthening helps to stabilize the pelvis. Dysfunction of the hip external rotators results in compensatory foot pronation; a simple stretch can improve muscular efficiency.4 Tight calf muscles Tight calves can lead to compensatory foot pronation and, like tight hamstrings, can increase the posterior force on the knee.11,15,16  NOTE: Exercises to treat the various muscular causes are illustrated in the  HYPERLINK "http://www.aafp.org/afp/991101ap/991101b.html" patient information handout that follows this article. Information from references 3, 4, 6, 7, 9 through 11, and 14 through 23.  INCLUDEPICTURE "http://www.aafp.org/afp/991101ap/spacer.gif" \* MERGEFORMATINET  Footwear Athletic and walking shoes have improved significantly in the past decade, perhaps to the point of confusion as so many choices are now available. Generally speaking, the quality and age of footwear are more important than the brand name. It is not uncommon to hear patients state that a new, quality shoe helped alleviate their knee pain. Most runners, for example, change their shoes every 300 to 500 miles. It would benefit the physician to become familiar with one or two reputable footwear stores that provide good customer service. Arch Supports and Custom Orthotics Arch supports or custom orthotics can be helpful in patients with a wide variety of lower extremity complaints, including patellofemoral pain.33,34 Although the reasons are not entirely clear, an arch support may improve lower extremity biomechanics by preventing overpronation in pes planus and by providing a broader base of support for the normal or pes cavus foot. Over-the-counter arch supports are a reasonable and relatively inexpensive initial suggestion. Custom orthotics may be worth a try if an over-the-counter insert is not helpful, although the expense is greater and superior efficacy has not been clearly established. Surgery Surgery for patellofemoral pain syndrome is considered a last resort. True chondromalacia (fraying of the retropatellar cartilage) may be amenable to an arthroscopic surgical procedure to smooth out the undersurface of the patella.35 Unfortunately, the chondromalacia may return. If the problem is clearly caused by excessive lateral tracking, a "lateral release" is sometimes appropriate. This procedure involves cutting the lateral retinaculum to reduce the amount of lateral pull. Before the decision is made to perform a lateral release, other options and treatments should be considered. For example, the physician should consider whether the lateral tracking could simply be due to a tight iliotibial band or weak quadriceps muscles. Taping the knee to enhance medial glide should be tried. Having the patient wear a quality running shoe or arch support is another measure to try before surgery is contemplated. Although the lateral release is effective in a select group of patients, it is often considered an overused procedure, even among some orthopedic surgeons.3 Spontaneous Resolution Spontaneous resolution of patellofemoral pain may occur,5,25,36 although many patients have already tried a "wait and see" approach by the time they seek medical treatment. Patellofemoral pain may be related to normal musculoskeletal development in some children and adolescents.25,26 For this reason, a conservative approach is preferred in the skeletally immature patient. Imaging Imaging should be considered to rule out unusual conditions such as osteochondritis dissecans, infection or neoplasm. In general, six weeks of no improvement in a compliant patient, particularly if the symptoms are unilateral, is a reasonable period to wait before ordering plain-film radiographs. Treatment Recommendations An initial conservative approach to patients with patellofemoral pain syndrome should include the following measures: (1) relative rest with consideration of a temporary change to nonimpact aerobic activity; (2) quadriceps strengthening; (3) evaluation of footwear; and (4) icing, especially after activity. Definitive treatment should be individualized. The addition of hip strengthening and stretching or stretching of the iliotibial band, hamstrings and calves should be based on a physical examination. Consideration should also be given to use of over-the-counter or custom orthotics. Patient education is essential, and patients need to be given realistic treatment expectations. Even though the etiology and treatment of patellofemoral pain syndrome remain uncertain, the good news is that most patients do well with conservative treatment, particularly if they maintain a disciplined approach.  The Author MARK S. JUHN, D.O., is a clinical instructor in the Department of Family Medicine at the University of Washington School of Medicine, Seattle. He is also a preceptor of family medicine residents and a staff physician in the sports medicine clinic at the university's Hall Health Primary Care Center. A graduate of the University of Medicine and Dentistry of New Jersey School of Osteopathic Medicine, Stratford, he completed a residency in family medicine at Garden City (Mich.) Osteopathic Hospital and a fellowship in primary care sports medicine at San Jose Medical Center/ Stanford University. He is board-certified in family medicine and holds a Certificate of Added Qualifications in sports medicine. Address correspondence to Mark S. Juhn, D.O., Hall Health Primary Care Center, University of Washington, Box 354410, Seattle, WA 98195-4410. Reprints are not available from the author. REFERENCES Cutbill JW, Ladly KO, Bray RC, Thorne P, Verhoef M. Anterior knee pain: a review. Clin J Sport Med 1997;7:40-5. Koh TJ, Grabiner MD, De Swart RJ. In vivo tracking of the human patella. J Biomech 1992;25:637-43. Reid DC. Sports injury assessment and rehabilitation. New York: Churchill Livingstone, 1992:345-98. Brukner P, Khan K. Clinical sports medicine. Sydney, Australia: McGraw-Hill, 1993:372-91. Finestone A, Radin EL, Lev B, Shlamkovitch N, Wiener M, Milgrom C. Treatment of overuse patellofemoral pain. Prospective randomized controlled clinical trial in a military setting. Clin Orthop 1993;(293):208-10. Thomee R, Renstrom P, Karlsson J, Grimby G. Patellofemoral pain syndrome in young women. I. A clinical analysis of alignment, pain parameters, common symptoms and functional activity level. Scand J Med Sci Sports 1995;5:237-44. Tria AJ Jr, Palumbo RC, Alicea JA. Conservative care for patellofemoral pain. Orthop Clin North Am 1992;23:545-54. Milgrom C, Finestone A, Shlamkovitch N, Giladi M, Radin E. Anterior knee pain caused by overactivity: a long term prospective followup. Clin Orthop 1996;331:256-60. Kannus P, Niittymaki S. Which factors predict outcome in the nonoperative treatment of patellofemoral pain syndrome? A prospective follow-up study. Med Sci Sports Exerc 1994;26:289-96. Natri A, Kannus P, Jarvinen M. Which factors predict the long-term outcome in chronic patellofemoral pain syndrome? A 7-yr prospective follow-up study. Med Sci Sports Exerc 1998;30:1572-7. Zappala FG, Taffel CB, Scuderi GR. Rehabilitation of patellofemoral joint disorders. Orthop Clin North Am 1992;23:555-66. Caylor D, Fites R, Worrell TW. The relationship between quadriceps angle and anterior knee pain syndrome. J Orthop Sports Phys Ther 1993;17:11-6. Tomsich DA, Nitz AJ, Threlkeld AJ, Shapiro R. Patellofemoral alignment: reliability. J Orthop Sports Phys Ther 1996;23:200-8. Callaghan MJ, Oldham JA. The role of quadriceps exercise in the treatment of patellofemoral pain syndrome. Sports Med 1996;21:384-91. Doucette SA, Goble EM. The effect of exercise on patellar tracking in lateral patellar compression syndrome. Am J Sports Med 1992;20:434-40. LaBrier K, O'Neill DB. Patellofemoral stress syndrome. Current concepts. Sports Med 1993;16: 449-59. O'Neill DB, Micheli LI, Warner JP. Patellofemoral stress. A prospective analysis of exercise treatment in adolescents and adults. Am J Sports Med 1992; 20:151-6. Cerny K. Vastus medialis oblique/vastus lateralis muscle activity ratios for selected exercises in persons with and without patellofemoral pain syndrome. Phys Ther 1995;75:672-83. Powers CM, Landel R, Perry J. Timing and intensity of vastus muscle activity during functional activities in subjects with and without patellofemoral pain. Phys Ther 1996;76:946-55. Laprade J, Culham E, Brouwer B. Comparison of five isometric exercises in the recruitment of the vastus medialis oblique in persons with and without patellofemoral pain syndrome. J Orthop Sports Phys Ther 1998;27:197-204. Mirzabeigi E, Jordan C, Gronley JK, Rockowitz NL, Perry J. Isolation of the vastus medialis oblique muscle during exercise. Am J Sports Med 1999; 27:50-3. Puniello MS. Iliotibial band tightness and medial patellar glide in patients with patellofemoral dysfunction. J Orthop Sports Phys Ther 1993;17: 144-8. Winslow J, Yoder E. Patellofemoral pain in female ballet dancers: correlation with iliotibial band tightness and tibial external rotation. J Orthop Sports Phys Ther 1995;22:18-21. Arroll B, Ellis-Pegler E, Edwards A, Sutcliffe G. Patellofemoral pain syndrome. A critical review of the clinical trials on nonoperative therapy. Am J Sports Med 1997;25:207-12. Nimon G, Murray D, Sandow M, Foodfellow J. Natural history of anterior knee pain: a 14- to 20-year follow-up of nonoperative management. J Pediatr Orthop 1998;18:118-22. Sandow MJ, Goodfellow JW. The natural history of anterior knee pain in adolescents. J Bone Joint Surg [Br] 1985;67:36-8. Greenwald AE, Bagley AM, France EP, Paulos LE, Greenwald RM. A biomechanical and clinical evaluation of a patellofemoral knee brace. Clin Orthop 1996;324:187-95. Bockrath K, Wooden C, Worrell T, Ingersoll CD, Farr J. Effects of patella taping on patella position and perceived pain. Med Sci Sports Exerc 1993;25:989-92. Gilleard W, McConnell J, Parsons D. The effect of patellar taping on the onset of vastus medialis obliquus and vastus lateralis muscle activity in persons with patellofemoral pain. Phys Ther 1998;78:25-32. Kowall MG, Kolk G, Nuber GW, Cassisi JE, Stern SH. Patellar taping in the treatment of patellofemoral pain. A prospective randomized study. Am J Sports Med 1996;24:61-6. McConnell JS. The management of chondromalacia patellae: a long-term solution. Aust J Physiotherapy 1986;32:215-23. Powers CM, Landel R, Sosnick T, Kirby J, Mengel K, Cheney A, et al. The effects of patellar taping on stride characteristics and joint motion in subjects with patellofemoral pain. J Orthop Sports Phys Ther 1997;26:286-91. Gross ML, Davlin LB, Evanski PM. Effectiveness of orthotic shoe inserts in the long-distance runner. Am J Sports Med 1991;19:409-12. Eng JJ, Pierrynowski MR. Evaluation of soft foot orthotics in the treatment of patellofemoral pain syndrome. Phys Ther 1993;73:62-70 [Published erratum in Phys Ther 1993;73:330]. Federico DJ, Reider B. Results of isolated patellar debridement for patellofemoral pain in patients with normal patellar alignment. Am J Sports Med 1997;25:663-9. Thomee R. A comprehensive treatment approach for patellofemoral pain syndrome in young women. Phys Ther 1997;77:1690-703. Copyright 1999 by the American Academy of Family Physicians. This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP. Contact  HYPERLINK "mailto:afpserv@aafp.org" afpserv@aafp.org for copyright questions and/or permission requests.  Physical Therapy Corner: Iliotibial Band Friction Syndrome Treatment http://www.nismat.org/ptcor/itb_stretch/ What is iliotibial band friction syndrome? It is a condition characterized by pain localized over the lateral femoral epicondyle that occurs during vigorous walking, hiking or running. The pain is usually relieved by rest and by walking with the knee held in full extension. However, when ambulation and knee flexion are resumed, symptoms return. What is the iliotibial band (ITB)? The iliotibial band is a tendinous extension of the fascia covering the gluteus maximus and tensor fascia latae muscles proximally. It descends distally to attach to the lateral condyle of the tibia. It also sends fibers to the lateral aspect of the patella (knee cap). Essentially, the ITB is the linkage between the pelvis, upper leg, and lower leg. Pathology to any structure linked to one of these areas may cause ITB contracture. What is a possible cause of iliotibial band friction syndrome? Overuse may cause shortening of the ITB. The knee goes from flexion to extension and excessive pressure from the ITB causes friction over the lateral femoral epicondyle. This repeated motion produces inflammation of the underlying structures and causes pain. What are the facts concerning iliotibial band friction syndrome? Pain localized over lateral femoral condyle Discomfort initially relieved by rest Pain may radiate toward the lateral joint line and proximal tibia Worse if a person continues to run No symptoms of internal derangement Symptoms frequently develop during downhill running Inadequate stretching program Which anatomic factors may be associated with iliotibial band friction syndrome? Hip abduction contracture (ITB tightness) Genu varum (Bow legging) Heel and foot pronation Tight heel cords Internal tibial torsion (Inward rotation of the leg) What are the treatments of iliotibial band friction syndrome? 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