Editorial Commentary: Do Patients With Femoroacetabular Impingement Syndrome Already Show Hip Muscle Atrophy?

Abstract

Muscle atrophy, fatty degeneration, and strength deficits of the hip abductors, flexors, and even external rotators are well-known clinical and radiologic findings in patients with advanced hip osteoarthritis. More recently, in the context of prearthritic hip diseases, the role of hip muscle function in femoroacetabular impingement syndrome (FAIS) has gained greater focus for hip surgeons. Several studies have shown that patients with FAIS present with activation deficits of the hip muscles, which may result in hip muscle weakness. Nevertheless, previous studies have yet to determine whether young and mainly active patients with FAIS already show hip muscle atrophy. Future research is required to further characterize hip muscle function in patients with FAIS. Of particular interest is the investigation of whether both qualitative (muscle fatty degeneration) and quantitative (muscle atrophy) morphologic alterations of the hip muscles are present in patients with FAIS, as well as whether these alterations are sex specific and/or related to the underlying hip morphology.

Hip Arthroscopy Followed by 6-Month Rehabilitation Leads to Improved Periarticular Muscle Strength, Except for Abductors and External Rotators

“…Beyond that, it remains difficult to evaluate whether such improvements are clinically relevant since reaching a strength level exhibited at a pathologic status is surely insufficient. 38 , 39 Owing to the work published by Casartelli et al., 36 it seems that FAI patients, before being operated on, present at this time point a global strength deficit of 16% on average for most hip muscles compared to healthy matched participants. This threshold, even though being unspecific to each muscle, approximates well the 15% we chose as a clinically relevant change for hip muscle strength.…”

Evolution of Hip Muscles Strength in Femoroacetabular Impingement Patients Treated by Arthroscopy or Surgical Hip Dislocation: A Retrospective Exploratory Study

“…Even though not all hip muscles were affected solely by surgery, it remains important to note that patients can present preoperative muscle weakness due to FAI syndrome, notably in abduction (11%), external rotation (18%), flexion (26%) and adduction (28%) [ 19 , 20 , 21 ]. Thus, the absence of strength reduction on the operated hip following surgery should not be necessarily considered as satisfactory.…”

“…The rehabilitation programs are, therefore, of great importance and can be guided by assessments of patient functional status, such as range of motion, specific tests and bilateral strength evaluation. Hip muscle strength in FAI patients is a topic of interest since it is reduced by the pathology itself [ 19 , 20 , 21 ] and additionally affected by surgery [ 12 , 16 , 17 ]. Noteworthily, muscle strength is one of the last clinical parameters measured in common practice, although it has been reported as the most adequate proxy for patient functional progression and surgical success [ 22 ].…”

Sex-Specific Differences in Hip Muscle Cross-sectional Area and Fatty Infiltration in Patients With Femoroacetabular Impingement Syndrome

“…21 To better understand some of the factors underlying these sex-specific differences in hip muscle strength as well as hip symptoms and function, it appears legitimate to investigate quantitative and qualitative properties of the main hip muscles in male vs female patients with FAIS. 7 Hence, the main aims of this study were to compare hip muscle CSA asymmetries (primary outcome) and fatty infiltration (secondary outcome) between men and women with FAIS. It was hypothesized that women would show greater muscle atrophy and fatty infiltration than men.…”