Hip+Bursitis+Diagnosis

flat =__ Introduction __= **Our Purpose:** Developing a pragmatic approach to diagnosing greater trochanteric hip bursitis.

In 1923, palpable tenderness to the lateral aspect of the hip was named trochanteric bursitis. Today it is commonly mistaken for other conditions. In order for an injury to be bursitis there needs to be inflammation of the bursae. In short, edema, redness, and erythema should all be present. Currently, due to the amount of symptoms that may occur at the greater trochanter, pain in that area is referred to as greater trochanteric pain syndrome. [31]  Greater Trochanteric Pain Syndrome (GTPS) is clinically defined as when there is pain over the greater trochanter during palpation when the patient is side-lying. [27]
 * Greater Trochanteric Bursitis vs. Greater Trochanteric Pain Syndrome **



GTPS includes greater trochanteric bursitis, external coxa saltans (snapping hip), and tears of the gluteus medius and minimus. This syndrome is relatively common and is present in the general population somewhere between 10-25%. [30]  The population at a higher risk for GTPS are females, and individuals with osteoarthritis of the knee, low back pain and IT Band tenderness. 17.6% of individuals with knee osteoarthritis are diagnosed with GTPS. [27] In adults with low back pain the prevalence is 20-35%. [11]

Greater trochanteric bursitis is very difficult to diagnose amongst other components of GTPS. Dynamic ultrasound and MRIs may be used as an exclusion tool for other diagnoses. [30] In their study on 24 females diagnosed with GTPS, Bird et al. found that only 2 patients had evidence of greater trochanteric bursitis. 15 women had gluteus medius tendonits and 11 had gluteus medius tears. [2] <span style="font-family: Arial,Helvetica,sans-serif;">In another study using MRIs, 14% of adults showed degenerative tears or tendonosis of the hip abductors, mostly gluteus medius. However, only 5% of the subjects showed bursal fluid accumulation. Of those subjects who did show accumulation there were also other factors contributing to their pain. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[14]



<span style="font-family: Arial,Helvetica,sans-serif;">Diagnosing and treating the specific contributors to GTPS may be difficult, and imaging is being used to detect abnormalities. X-rays can be used to see calcific tendinopathy or bursopathy. MRIs can detect changes to the gluteus medius and minimus. Ultrasonography is becoming more popular due to its cost, but it is very operator dependent. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[11] <span style="font-family: Arial,Helvetica,sans-serif;">Fearon et al. found that ultrasound can visualize bursal discharge, gluteus tendinopathy and tears. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[7] <span style="font-family: Arial,Helvetica,sans-serif;">Understanding the patient’s pathology will help one individualize a therapeutic plan appropriately.

=__ Pathophysiology & Epidemiology __= <span style="font-family: Arial,Helvetica,sans-serif;">Greater trochanteric bursitis refers to pathologic conditions occurring within the bursa located around the greater trochanter. Three to four main bursa are typically located in this area. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31] <span style="font-family: Arial,Helvetica,sans-serif;">These are the gluteus minimus, the subgluteus maximus, and the subgluteus medius bursa. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31] <span style="font-family: Arial,Helvetica,sans-serif;">The largest of these is the subgluteus maximus bursa, and it is the most commonly reported in GTB2. The location of these bursa as well as their pain referral patterns differ from person to person making it difficult to distinguish GTB from other relating conditions. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31] <span style="font-family: Arial,Helvetica,sans-serif;">In addition, the etiology of this condition is not well known, and signs of inflammation associated with bursitis have not been well documented. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31,1,29]
 * <span style="font-family: Arial,Helvetica,sans-serif;">Pathophysiology **



<span style="font-family: Arial,Helvetica,sans-serif;">Most commonly occurs from trauma or overuse. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31] <span style="font-family: Arial,Helvetica,sans-serif;">Trauma such as falling on the hip can cause injury to the bursa. Overuse of the muscles of the hip results in repetitive movements that increase friction and can irritate the bursa. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31,23] <span style="font-family: Arial,Helvetica,sans-serif;">Commonly associated muscles include the gluteus medius, minimus, and maximus, and the TFL. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31,23] <span style="font-family: Arial,Helvetica,sans-serif;">Other causes included leg length discrepancy, muscle dysfunction, and infection. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 60%; vertical-align: super;">[31,23]
 * Mechanism of Injury**


 * <span style="font-family: Arial,Helvetica,sans-serif;">Epidemiology **
 * Most common in adults age 40-60<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[27,31]
 * 10-20% reported occurrence is adults 60 years or older<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[27,31]
 * 1.8 out of 1000 cases per year involve greater trochanteric pain in primary care settings
 * Higher reported prevalence in women than men.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[27]
 * Increased occurrence associated with lower back pain, osteoarthritis, ilio-tibial band tenderness, and obesity.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[27,31]
 * Reported 20-35% occurrence of GTPS in patients with musculoskeletal related lower back pain.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[27,31]

=__Signs & Symptoms__= There are four main types of hip bursitis, but the most common area where bursitis occurs is in the greater trochanteric region, which will be the main focus of this section. This condition affects as many as 5.6 out of every 1,000 adults, but is most commonly observed in the middle-aged population (40-60 years of age).<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[3] It is more commonly observed in women as opposed to men at about a 4:1 ratio.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[24] There are numerous signs and symptoms associated with greater trochanteric hip bursitis. A common way this condition presents itself is as chronic, but non-constant pain over the lateral hip. Tenderness and pain will be felt by the patient when the clinician palpates over this trochanteric region in the lateral hip. The patient might especially be sensitive to pain when palpation occurs over the superior and posterior regions of the greater trochanter.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[4] A good amount of tenderness can usually be noted over the iliotibial band as well as the insertion point for the gluteus medius muscle.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[4] A patient might complain of pain in the lateral hip traveling down the lateral portion of the leg and ceasing at the knee as well feeling pain when walking and/or running, pain when climbing stairs, or a generalized feeling of weakness in the affected leg.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[4,22] Of these aforementioned complaints, the activity that has been noted to induce the most pain related to the hip bursitis is stair climbing.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[22] An additional sign that bursitis is the cause of the pain in the lateral hip is if the patient reports a popping or snapping sensation in the hip when walking, running, or stair climbing.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.60000038146973px; vertical-align: super;">[26] <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.60000038146973px;"> In addition to these movements, kinesiological motions that can aggravate a patient’s pain is either actively performing abduction or passively moving the patient through adduction.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[3,25]

Hip bursitis is correlated with other activities not specifically related with physical activity. For example, a common complaint from patients suffering from greater trochanteric bursitis is that it is too painful to lie down on the affected side.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[24] Bursitis in the hip is also an observed side effect of having a hip arthroplasty. One study has noted that the incidence of this post-operative complication to be noted in anywhere from 4-15% of hip arthroplasty patients, with the range being accounted for by the pain in the greater trochanteric region being possibly associated with issues other than bursitis specifically.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[12] Another important factor to note is that hip bursitis can be associated with low back pain.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[18] With PT referrals relating to low back pain being so common in this day and age, the clinician should ask if any back pain or tenderness is also present.

=__Diagnostic Tests__= Greater trochanteric bursitis is hard to find clinically. It's symptoms co-exist with a multitude of other injuries, and therefore the literature combines greater trochanteric bursitis with gluteus medius tears/strains and gluteus minimus tears/strains. These combined pathologies are called greater trochanteric pain syndrome (GTPS), and the bulk of research uses clinical tests to find GTPS and gives specificity and sensitivity of these clinical tests. The tests used to find greater trochanteric bursitis more specifically are palpation "jump sign", single leg stance test (Trendelenburg), and resisted external derotation in the supine position.

By far in literature the palpation ("jump sign") of the lateral hip over the greater trochanter is stated as the key clinical sign for greater trochanteric bursiti s. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[31,21,20,8] Thi s is simply done by placing the patient prone, flexing the knee, and rotating the knee internally and externally. While completing the sequence stated above use the other hand to palpate the greater trochanteric region feeling for the rotating greater trochanter. If this is were the patient describes the pain and your palpation reproduces pain then it is considered a positive finding. As much as this has been noted in literature, not much research has been done on the specificity or sensitivity of palpation. Inter-tester error for finding the greater trochanter as a landmark is 15mm or greater, which is bigger than the area of the bursa itself.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[21] This could lead to evidence for a low specificity, but a study by Martin, R., & Sekiya, J., 2008 showed a Kappa score of .66 which is classified as good inter-tester reliability to find tenderness over the trochanter. They did, however, state that although testers could identify tenderness over the trochanter, it did not identify the underlying condition. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[19]
 * Jump Sign**

Arguably the best test, statistically, for greater trochanter bursitis is the Trendelenburg or single leg stance test. It is performed by simply having the patient stand on the affect side for 30 seconds and look for the pelvis to drop or the lumbar spine to side bend in compensation for weak hip abductors secondary to pain. If this stance reproduces the pain in the lateral hip, it is considered a positive finding. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[16] Lequesne, et. al. found that the sensitivity and specificity for this test is 100% and 97.3% respectively. It is appropriate to note that Trendelenburg test is also a fairly sensitive and fairly specific test for tendon tears in the lateral hip with statistics of 72.7% sensitive and 76.9% specific. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[2]
 * Trendelenburg**

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Lastly, the resisted external derotation in the supine position test is also a good test for greater trochanter bursitis. It is performed by starting the patient in the supine position, flexing the hip 90%, flexing the knee 90%, and externally rotating the hip. Then the tester will instruct the patient to try and return their leg to the anatomical position on the table (return to normal). As the patient is trying to return the affected leg to the table, the tester will provide resistance and ask if the maneuver reproduces the hip pain, confirming a positive test. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[16] This particular test has a sensitivity of 88% and a specificity of 97.3%. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[16]
 * Resisted External Derotation**

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It is important to note that a myriad of other tests are used to try and find greater trochanter bursitis, including resisted abduction and Obers, but this have shown poor sensitivity and specificity percentages. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[2,21] Once again it is important to state that greater trochanter bursitis is a difficult condition to find clinically, but with signs and symptoms coupled with the few diagnostic tests and some imaging, this condition should not be missed. More research on the topic is warranted.
 * Other Diagnostic Tests**

=__Medical Imaging__= <span style="font-family: Arial,Helvetica,sans-serif;">The physical exam plays the primary role in diagnosing trochanteric bursitis but imaging will often play a part. There are three types of medical imaging that are commonly used and they include: magnetic resonance imaging (MRI), ultrasound, and x-ray. Bird et al stated that several authors have described a limited role for imaging in confirming a trochanteric bursitis diagnosis. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[2] <span style="font-family: Arial,Helvetica,sans-serif;">Silva et al similarly state that t <span style="color: #0a0905; font-family: Arial,Helvetica,sans-serif;">he diagnosis of trochanteric bursitis remains a clinical one. The role for MRI is increasing in this condition but mainly in cases that do not respond to local corticosteroid injections and physical therapy. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[29]

<span style="font-family: Arial,Helvetica,sans-serif;">A T2 weighted MRI is considered the most beneficial when diagnosing trochanteric bursitis due to its ability to detect edema and asymmetric sites of fluid accumulation. A fluid sensitive T2 would be beneficial to detect muscular strain, tears, or soft tissue lesions that may accompany trochanteric bursitis. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[28] <span style="font-family: Arial,Helvetica,sans-serif;"> MRI can be effective at detecting fluid accumulation it is important to note that Oakley et al performed a retrospective review of MRIs obtained in patients with trochanteric bursitis as defined by lateral hip pain plus tenderness. While almost all patients had gluteus medius abnormalities, swelling of the trochanteric bursae was remarkably uncommon. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[1]
 * <span style="font-family: Arial,Helvetica,sans-serif;">Magnetic Resonance Imaging **<span style="font-family: Arial,Helvetica,sans-serif;">(What is MRI?)

<span style="font-family: Arial,Helvetica,sans-serif;">Reading a MRI for trochanteric bursitis:
 * <span style="font-family: Arial,Helvetica,sans-serif;">Asymmetrical collection of fluid
 * <span style="font-family: Arial,Helvetica,sans-serif;">Presence of bursal distension <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[28]

**Ultrasound** (What is ultrasound?) Ultrasound can provide dynamic images of the joints, muscles, tendons, or soft tissues. These images can be used to examine muscles and tendons for tears, damage or erosion of the joint, and fluid collections. Ultrasound can be used to rule out several other hip pathologies while at the same time examining for bursitis. A normal bursa of the hip are imperceptibly thin but trochanteric bursitis will be evident through a distended bursa. <span style="color: #343434; font-family: Arial,Helvetica,sans-serif;">The advantages over MRI include lower cost, greater accessibility, and the ability to compare imaging findings with tenderness at the time of the examination. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[32] <span style="font-family: Arial,Helvetica,sans-serif;"><span style="font-family: Arial,Helvetica,sans-serif;">Mayordormo et al reported ultrasound examination findings in 15 patients with GTPS compared with 13 controls. Bursal enlargement was identified in 85% of symptomatic patients and 30% of the patients in the asymptomatic control group. The authors noted that the mean thickness of the bursa was significantly greater in the symptomatic group (mean ± SD: 4 ± 1.6 mm) than in the asymptomatic group (mean ± SD: 2.6 ± 0.9 mm). <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[2] Ultrasound can also be used to guide the placement of a needle directly into the bursa to inject corticosteriod and local anasethetic medication. This is not only a form of treatment but can be seen as a diagnostic test. If symptoms temporarily subside after injection then that could be a positive test for trochanteric bursitis.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[32]

**X-ray** (What is x-ray?) <span style="font-family: Arial,Helvetica,sans-serif;">Normally, x-ray of the hip is suggested to rule out other conditions of the bone and joints, such as arthritis and fractures. At times it can be <span style="color: #050505; font-family: Arial,Helvetica,sans-serif;">difficult to tell whether the pain you are suffering is from trochanteric bursitis or underlying arthritis of the hip joint. For this reason, an x-ray may give more information about the condition of the hip joint itself. On occasion with trochanteric bursitis calcifications around the greater trochanter may be seen (approximately 40% of patients with greater trochanteric bursitis). <span style="font-family: Arial,Helvetica,sans-serif;">These areas of calcification indicate a past history of inflammation of the bursa. An x-ray has the ability to highlight areas of calcium deposits in an inflamed bursa. These calcifications vary in size and shape from a few millimeters to 3 to 4 centimeters in diameter. On the x-ray they appear as linear or small, rounded masses that are separated or grouped together. These irregularities are seen on the surface of the greater trochanter.<span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[8] <span style="font-family: Arial,Helvetica,sans-serif;">Bird et al stated that calcification adjacent to the greater trochanter has been reported on x-rays of patients with GTPS, but this finding has thought to be nonspecific and it is not clear whether the calcification noted on x-rays is located in the tendon insertion or within the bursa. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[2] =__Conclusion__= <span style="color: #0a0905; font-family: Arial,Helvetica,sans-serif;">There are not a validated set of diagnostic criteria for trochanteric bursitis that have been developed. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 9.6px; vertical-align: super;">[1] There is no gold standard in diagnosing trochanteric bursitis which causes the examination to be multi-faceted. Diagnosing trochanteric bursitis is guided by the patient's presentation of signs and symptoms, a range of possible tests, screening differential diagnosises, and possible imaging. It is important to keep in mind that for this diagnosis it will be rare to have the trochanteric bursa involved in isolation. Other structures are often the cause of trochanteric bursitis and will need to be assessed in the examination. A diagnosis of trochanteric bursitis involves a multi-faceted approach that needs to take a comprehensive examination of the hip.

It is important to remember that lateral hip pain can stem from numerous causes, not all of which are specifically related to hip bursitis. The following audio file is a tool that can be utilized to not only guide you through a patient's symptoms, but also details what kind of tests one can observe to confirm this diagnosis. This tool has been officially approved by the APTA and medical institutions around the world.

media type="file" key="Hip song good.m4a" align="center" width="300" height="50"

media type="file" key="Hip song good.mp3" width="312" height="26" = __References__ =
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