Quads or quins? Atraumatic restricted knee flexion due to accessory quadriceps bands in children

Not an arthritis, but a fibrotic band of the quadriceps muscle: A case report of unilateral restricted knee flexion in an adolescent

“…In most of the cases reported in the literature regarding the fibrotic band in the quadriceps, the localization of the fibrotic band is the tensor vastus intermedius or accessory quinticeps femoris, a newly defined muscle between the vastus intermedius and the vastus lateralis. 1,3,7,8,15 However, in our case, the fibrotic band localization was completely different, which was in the vastus lateralis muscle. The surgical method for fibrotic bands involves the direct excision of the band structure.…”

“…Nevertheless, the congenital fibrotic band has been less defined. 1,3,7,8 Fibrotic bands and fibrosis of the quadriceps are very similar in microscopy. Yet, these are two distinct conditions in terms of macroscopy that can be observed during surgery.…”

“…Although quadriceps muscle fibrosis is relatively common, fibrotic bands associated with the components of quadriceps are extremely rare, with a number of reports in the literature. 1,3,7,8 In this current article, an adolescent case with a fibrotic band of the vastus lateralis muscle will be presented and discussed along with the literature.…”

Quadriceps femoris muscle: anatomical variations, population frequencies and clinical implications

“…Furthermore, it should be noted that many of the studies made have a high risk of bias [29]. The clinical implications related to the existence of additional heads in the quadriceps femoris are evident as previously discussed in the results section [17,23,30,38] and certain lesions have been erroneously attributed to the vastus intermedius or lateralis instead of the tensor vastus intermedius when is present [20].…”

Anatomy, Morphology and Function of the Tensor of Vastus Intermedius: A Systematic Review

“…In particular, supplementary muscles are anatomic variants representing additional distinct muscles that are encountered between normal complement muscles [ 1 , 2 ]. Although they are generally asymptomatic and identified as incidental findings, sometimes they are considered a potential source of pain and clinical symptoms [ 3 , 4 ].…”