Ligament Teres Injury: An Uncommon Hip-Hop Hurt

Dear Editor, Ligamentum teres (LT) has two bands that finally attach over the fovea capitis of the femoral head. LT is considered as an important hip stabilizer, especially in hip flexion and external rotation.[1] Injury to the LT clinically presents with nonspecific hip pain and requires careful exclusion of various differentials. Localized groin pain, instability, or altered range-of-motion are common clinical features.[2] Older age and pathoanatomy of the acetabular region increase the risk of LT injury. A 32-year-old male presented with an acute painful left hip region for the last 2 months following a minor misstep during hip-hop routine. The pain increases with weight-bearing and gets relieved by rest and pain medications. Radiographs were unremarkable with no underlying bony abnormality. Magnetic resonance imaging (MRI) revealed no bony injury except hyperintensity or edema surrounding the LT with the contralateral side unaffected [Figure 1]. Apart from the injury, there was also the anatomical difference between both the fovea capitis with the affected left side being deep and notched as compared to the right side.Figure 1: The frontal (above) and axial (below) magnetic resonance imaging images showing the normal bony features around the bilateral hip joints. There is, however, the presence of edema around ligament teres (denoted by red arrows) on the left side as it attaches over the fovea capitis. The fovea capitis on the affected side is deeper and notched than the contralateral side, as an incidental findingOn the basis of clinical and radiological findings, diagnosis of LT injury or sprain was made. A period of conservative methods including rest to the extremity and crutch use was advised along with pain medication on as and when required basis. After a period of 5 weeks, clinical improvement was noted, and with another 2 weeks of protected ambulation, the patient was having painless ambulation and range of motion. MRI may be used to appreciate these injuries but may have lower sensitivity and specificity than magnetic resonance arthrography. Arthroscopic evaluation can confirm the final nature of the injury or tear.[3] Recently, edema of LT has been proposed as a marker for nontraumatic hip pathology like femoroacetabular impingement.[4] In 2.2% of asymptomatic people, however, MRI may display features of LT tear.[5] The other notable radiological feature here is dissimilar shapes of bilateral fovea capitis. The affected hip has deeper and triangular-shaped fovea, whereas the contralateral shape is shallower and oval. There have been three types of shapes described in a dry bones study: oval, circular, and triangular in decreasing order of their incidence.[6] This briefcase snippet is described here for the recognition of uncommon LT injury by appropriate investigation and clinical correlation. We advocate suspecting and keeping this injury as an uncommon differential diagnosis in cases with unexplained hip pain following the injury related with sports or recreational activity. Appropriate diagnosis results in optimal management, and the use of MRI helps in identifying subtle injuries of the ligamentous origin. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.