Anatomic Variance of the Iliopsoas Tendon

The American Journal of Sports Medicine (Impact Factor: 4.36). 01/2014; 42(4). DOI: 10.1177/0363546513518414
Source: PubMed


BACKGROUND:The iliopsoas tendon has been implicated as a generator of hip pain and a cause of labral injury due to impingement. Arthroscopic release of the iliopsoas tendon has become a preferred treatment for internal snapping hips. Traditionally, the iliopsoas tendon has been considered the conjoint tendon of the psoas major and iliacus muscles, although anatomic variance has been reported. HYPOTHESIS:The iliopsoas tendon consists of 2 discrete tendons in the majority of cases, arising from both the psoas major and iliacus muscles. STUDY DESIGN:Descriptive laboratory study. METHODS:Fifty-three nonmatched, fresh-frozen, cadaveric hemipelvis specimens (average age, 62 years; range, 47-70 years; 29 male and 24 female) were used in this study. The iliopsoas muscle was exposed via a Smith-Petersen approach. A transverse incision across the entire iliopsoas musculotendinous unit was made at the level of the hip joint. Each distinctly identifiable tendon was recorded, and the distance from the lesser trochanter was recorded. RESULTS:The prevalence of a single-, double-, and triple-banded iliopsoas tendon was 28.3%, 64.2%, and 7.5%, respectively. The psoas major tendon was consistently the most medial tendinous structure, and the primary iliacus tendon was found immediately lateral to the psoas major tendon within the belly of the iliacus muscle. When present, an accessory iliacus tendon was located adjacent to the primary iliacus tendon, lateral to the primary iliacus tendon. CONCLUSION:Once considered a rare anatomic variant, the finding of ≥2 distinct tendinous components to the iliacus and psoas major muscle groups is an important discovery. It is essential to be cognizant of the possibility that more than 1 tendon may exist to ensure complete release during endoscopy.Clinical Significance:Arthroscopic release of the iliopsoas tendon is a well-accepted surgical treatment for iliopsoas impingement. The most widely used site for tendon release is at the level of the anterior hip joint. The findings of this novel cadaveric anatomy study suggest that surgeons should be mindful that more than 1 tendon may be present and require release for curative treatment.

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    • "The CT scan shows part of the illiopsoas attached to each part of the bisected lesser trochanter with the proximal fragment locked in between. These patients may probably have a bifid illiopsoas tendon; a variant which is now well described [9] [10] [11]. We believe an important step to reduce this fracture is to section the illiopsoas attached onto the distal fragment and then reduce the flexed proximal fragment. "
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    ABSTRACT: To define the unique radiographic features, operative treatment, and complications of pertrochanteric fractures (AO/OTA 31-A1 and A2) which are not amenable to the usual closed reduction manoeuvres. During a 2-year period (from August 2011 until December 2013), 212 patients with pertrochanteric fractures were treated at our level I trauma centre. A retrospective review was undertaken to determine which of these fractures were not reducible via the routine closed reduction manoeuvres and required some form of open reduction. These fractures were assessed for radiographic markers of irreducibility, surgical findings, reduction techniques, and perioperative complications. Twenty-four patients had fractures, which were not amenable to closed reduction and underwent open reduction. These fractures could be grouped into four patterns. A preoperative CT scan was available for at least two cases of each pattern, which provided further insights into the cause of irreducibility by closed means. These included a variant where the proximal fragment is locked underneath the shaft fragment (3 cases), bisected lesser trochanter with a locked proximal fragment (3 cases), irreducibility due to entrapped posteromedial fragment at the fracture site (6 cases) and a variant where the proximal fragment is flexed passively by the underlying lesser trochanter (12 cases). Pertrochanteric fractures, which are not amenable to closed reduction, are uncommon, but are heralded by unique radiographic features. These patients warrant special consideration in terms of recognition and management. The specific radiographic markers should alert the surgeon to this injury pattern and its related difficulty encountered during closed reduction. Once reduction is achieved, however, these fractures follow an uneventful course. Copyright © 2014 Elsevier Ltd. All rights reserved.
    Injury 10/2014; 45(12):1950-1957. DOI:10.1016/j.injury.2014.10.007 · 2.14 Impact Factor
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    • "It is our own intraoperative observation that a bifid iliopsoas tendon is frequently present. This surgical observation has only been supported by scattered case reports in the international literature until recently [10, 18–20]. A fatty cleft between the iliopsoas tendon and a distinct tendon within the lateral part of the iliacus muscle has previously been described on MR hip arthrograms in adults [21]. "
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    ABSTRACT: Objective The variation in the anatomy of the iliopsoas tendon is important information for orthopaedic surgeons operating around the hip. The aim of this study was to identify the prevalence of bifid iliopsoas tendons in children on magnetic resonance imaging (MRI). Methods MRI hip and pelvis images of 50 sequential children aged 7–15 years were retrieved from our radiology database at the Evelina London Children’s Hospital from 2007 to 2013. Included were 37 children with imaging of both hips and 13 children with imaging of one hip only. Therefore, our study was based on a total of 87 hips. Results At least 1 bifid tendon was noted in 13 children (26 %). Five children from a total of 37 (14 %) with both hips adequately imaged had bilateral bifid tendons. Among all 87 adequately imaged hips, 18 (21 %) were found to have two discrete distal iliopsoas tendons. Conclusions Bifid iliopsoas tendon is noted anecdotally by surgeons but was only reported in scattered case reports and a few anatomical studies until very recently. Our finding is that a bifid iliopsoas tendon with two distinct tendinous components at the level of the hip joint is quite common. This has clinical significance, particularly in children’s orthopaedic surgery when an adequate iliopsoas release is important.
    Journal of Children s Orthopaedics 06/2014; 8(4). DOI:10.1007/s11832-014-0596-x
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    ABSTRACT: There is sparse information about the anatomy and function of the psoas minor, specifically the extent and frequency to which the muscle attaches into the iliac fascia that drapes over the iliopsoas. This information may help clarify the function of the psoas minor, especially regarding the possibility of controlling the position and mechanical stability of the underlying iliopsoas. This descriptive, semiquantitative cadaveric study sought to clarify the gross anatomic detail of the psoas minor, particularly the muscle's distal attachments. Thirty-two embalmed cadaver hips were examined. Hips that presented with a psoas minor underwent further anatomic measurements. The psoas minor was present in 65.6% of the 32 hips. All of the psoas minor tendons attached firmly into iliac fascia, while 90.5% also had a firm bony attachment to the pelvis. On average, the muscle belly occupied the proximal 37.5 ± 6.0% of the entire musculotendinous unit, while the muscle belly's average anatomical cross-sectional area was 52.5 ± 34.3 mm2. The psoas minor's firm and consistent distal tendinous attachment into the iliac fascia may allow this muscle to partially control the position and mechanical stability of the underlying iliopsoas as it crosses the femoral head and adjacent regions. This hypothesized function may be clinically related to inflammation and pathology involving the iliopsoas tendon and adjacent tissues in the anterior region of the hip. Further study is now warranted to determine the clinical relevancy and biomechanical validity of this proposed function of the psoas minor. Clin. Anat., 2014. © 2014 Wiley Periodicals, Inc.
    Clinical Anatomy 09/2014; 28(2). DOI:10.1002/ca.22467 · 1.33 Impact Factor