Imaging of rectus femoris proximal tendinopathies

Abstract

The rectus femoris is the most commonly injured muscle of the anterior thigh among athletes, especially soccer players. Although the injury pattern of the muscle belly is well documented, less is known about the anatomy and specific lesions of the proximal tendons. For each head, three distinctive patterns may be encountered according to the location of the injury, which can be at the enthesis, within the tendon, or at the musculotendinous junction. In children, injuries correspond most commonly to avulsion of the anteroinferior iliac spine from the direct head and can lead to subspine impingement. Calcific tendinitis and traumatic tears may be encountered in adults. Recent studies have shown that traumatic injuries of the indirect head may be underdiagnosed and that injuries of both heads may have a surgical issue. Finally, in the case of tears, functional outcome and treatment may vary if the rupture involves one or both tendons and if the tear is partial or complete. Thus, it is mandatory for the radiologist to know the different ultrasound and magnetic resonance imaging (MRI) patterns of these lesions in order to provide accurate diagnosis and treatment. The purpose of this article is to recall the anatomy of the two heads of rectus femoris, describe a reliable method of assessment with ultrasound and MRI and know the main injury patterns, through our own experience and literature review.

Soft tissue pseudotumours: a pictorial review with emphasis on MRI

“…Spontaneous rupture has also been described in patients with underlying predisposing metabolic disorders such as chronic renal failure, hyperparathyroidism, diabetes, gout and systemic lupus erythematosus 11,12,14,15 . The rupture typically occurs near the musculotendinous junction, and MRI can help in identifying and categorizing it as partial or complete tear 16 , thus influencing the prognosis, because a delay in surgical reconstruction is believed to adversely affect outcome 11,12,14,15 . Furthermore, in neglected cases or when clinical history is not clear, tendon tears may be mistaken clinically as soft tissue masses, and MRI nicely depicts the tendon tear, reassuring the patient and the referring physician (Fig.…”

“…On the other hand, mucoid degeneration with poor healing response and without an associated frank inflammatory process is evident in chronic forms 11,12,14,15 . MRI features include thickening of the tendon and signal alterations both on T1-weighted and T2-weighted sequences in the acute-subacute phase 18 .…”

“…thy is the result of repetitive microtrauma, and is characterized by inflammatory changes 11,12,14,15 . On the other hand, mucoid degeneration with poor healing response and without an associated frank inflammatory process is evident in chronic forms 11,12,14,15 .…”

“…Tendinopathy is common especially in young active patients involved in sports 11,12,14,15 . Tendon thickening, peritendinous oedema and pain may be mistaken as a soft tissue or tendon related tumour.…”

“…Tendon tears usually occur after an eccentric muscle contraction 11,12,14,15 . Spontaneous rupture has also been described in patients with underlying predisposing metabolic disorders such as chronic renal failure, hyperparathyroidism, diabetes, gout and systemic lupus erythematosus 11,12,14,15 .…”