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In order to investigate the functional anatomy of gluteus minimus we dissected 16 hips in fresh cadavers. The muscle originates from the external aspect of the ilium, between the anterior and inferior gluteal lines, and also at the sciatic notch from the inside of the pelvis where it protects the superior gluteal nerve and artery. It inserts anterosuperiorly into the capsule of the hip and continues to its main insertion on the greater trochanter. Based on these anatomical findings, a model was developed using plastic bones. A study of its mechanics showed that gluteus minimus acts as a flexor, an abductor and an internal or external rotator, depending on the position of the femur and which part of the muscle is active. It follows that one of its functions is to stabilise the head of the femur in the acetabulum by tightening the capsule and applying pressure on the head. Careful preservation or reattachment of the tendon of gluteus minimus during surgery on the hip is strongly recommended.
Content may be subject to copyright.
M. Beck, MD
C. F. Dora, MD
R Ganz, MD
Clinic of Orthopaedic Surgery, University of Berne, Inselspital, 3010
Berne, Switzerland.
E. Gautier, MD
Department of Orthopaedic Surgery, Hôpital Cantonal, 1708 Fribourg,
J. B. Sledge, MD
Department of Orthopaedics, Boston Medical Centre, 818 Harrison Ave-
nue, Dowling, 2 North Boston, Massachusetts 02188, USA.
Correspondence should be sent to Dr M. Beck.
©2000 British Editorial Society of Bone and Joint Surgery
0301-620X/00/310356 $2.00
The anatomy and function of the gluteus
minimus muscle
Martin Beck, John B. Sledge, Emmanuel Gautier, Claudio F. Dora,
Reinhold Ganz
From the University of Berne, Switzerland
n order to investigate the functional anatomy of
gluteus minimus we dissected 16 hips in fresh
cadavers. The muscle originates from the external
aspect of the ilium, between the anterior and inferior
gluteal lines, and also at the sciatic notch from the
inside of the pelvis where it protects the superior
gluteal nerve and artery. It inserts anterosuperiorly
into the capsule of the hip and continues to its main
insertion on the greater trochanter.
Based on these anatomical findings, a model was
developed using plastic bones. A study of its
mechanics showed that gluteus minimus acts as a
flexor, an abductor and an internal or external rotator,
depending on the position of the femur and which
part of the muscle is active. It follows that one of its
functions is to stabilise the head of the femur in the
acetabulum by tightening the capsule and applying
pressure on the head. Careful preservation or
reattachment of the tendon of gluteus minimus during
surgery on the hip is strongly recommended.
J Bone Joint Surg [Br] 2000;82-B:358-63.
Received 12 July 1999; Accepted after revision 18 August 1999
Knowledge of the anatomical relationships and function of
gluteus minimus is limited. It is described as a fan-shaped
muscle arising from the external iliac fossa between the
anterior and inferior gluteal lines and covered almost
entirely by gluteus medius.
Reports of the exact site of
the insertion of the tendon of gluteus minimus vary. Some
describe it as at the anterior surface of the greater trochan-
and some to the external side of the anterior rim of
the greater trochanter and the superior aspect of the cap-
sule of the hip. More recently, it has been reported to be at
the ventral triangular area of the greater trochanter.
French literature has it at the tubercule
The function of gluteus minimus is also uncertain. Both
minimus and medius have been described as having essen-
tially the same function, primarily abduction, with internal
rotation and flexion being possible, depending on the
position of the femur.
Based on anatomical and electromyographic studies,
Gottschalk, Kourosh and Leveau
proposed a different
model of the gluteus complex. They declared that the
primary function of the entire gluteus minimus and the
posterior part of gluteus medius is to stabilise the head of
the femur in the acetabulum during the gait cycle.
Our interest in this muscle was raised by the observa-
tion of a lateral indentation in the head of the femur in
patients with spastic diplegia of the hip (Fig. 1). In the
course of periacetabular osteotomy with an inter-
trochanteric osteotomy, we found gluteus minimus in this
indentation, separated by the capsule. We deduced that this
appearance was due to pressure by gluteus minimus as it
resisted superolateral migration of the head. Notching of
the head has previously been described in patients with
cerebral palsy and was attributed either to a taut liga-
mentum teres,
the overlying capsule, spastic abductor
or to the rim of the acetabulum.
Materials and Methods
We studied the anatomy of gluteus minimus in 16 hips
from nine cadavers, of which eight were fresh and one
embalmed. There were nine right and seven left hips. The
age at death had varied between 45 and 80 years.
The dissection was carried out with the cadaver in the
lateral position. After removal of the skin and subcuta-
neous tissue, the fascia over gluteus maximus and medius
was incised in the interval between the two muscles.
Gluteus maximus was then detached from the ilium and
reflected posteriorly. Next, gluteus medius was dissected
off gluteus minimus in a distal-to-proximal and posterior-
to-anterior direction. Based on our anatomical findings, a
model of gluteus minimus was developed, attached to
plastic bones of a hemipelvis and proximal femur (Fig. 2).
A prosthetic hip was implanted to provide a normal range
of movement. The joint capsule was simulated using a
broad rubber sheet, glued to the anterosuperior circum-
ference of the acetabulum and to the intertrochanteric line
on the proximal femur. The muscle was divided into four
identical sectors, sector I being the most anterior and
sector IV, the most posterior. Each sector was represented
by a cord 2 mm thick, which was firmly fixed at its
insertion on the greater trochanter and directed through
pulleys on the capsule of the hip and at its origin. The
excursion of each cord was measured independently.
Schanz screws were inserted at right angles into the
greater trochanter to control and measure the degrees of
rotation and flexion. Three measurements were made for
each directional movement, starting with the hip in the
neutral position and the mean value was calculated. The
measurements were taken for flexion, external and internal
rotation in both the extended and flexed position, and for
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Fig. 1a
Fig. 1b
Fig. 1c
A 14-year-old-girl with spastic diplegia. Figure 1a –
Preoperative radiograph with a superolateral inden-
tation of the head of the femur. Figures 1b and 1c
– Intraoperative view of the head (1) after osteot-
omy of the greater trochanter (2). Gluteus minimus
(3) is retracted superiorly, with excellent visual-
isation of the groove (4) in the head. Gluteus mini-
mus (3) is released and lies in the indentation. The
joint capsule is seen (5).
Fig. 2
A model of gluteus minimus. Four different sectors of the muscle are
represented by cords, guided through pulleys, which represent the attach-
ment to the capsule and the origin of the muscle. The excursion is
measured on the scale (left).
The gluteus minimus muscle arises from the external iliac
fossa. From there the fibres converge, crossing the hip
anterolaterally to their insertion on the front of the greater
trochanter. The line of origin begins anteriorly 3 to 5 mm
below the anterior superior iliac spine and runs posteriorly,
parallel to the iliac crest to the iliac tubercule. From there it
follows the anterior gluteal line to the greater sciatic notch
from where the caudal portion of the muscle takes its origin
inside the pelvis (Fig. 3). The posteroinferior border of the
muscle covers the posterosuperior acetabulum and follows
the inferior gluteal line to the anteroinferior iliac spine.
Anteriorly, gluteus minimus arises from the ridge between
the anterosuperior and anteroinferior iliac spines.
The muscle fibres converge from the area of origin to a
tendinous insertion into the capsule of the joint. They
measure about 4 cm in length and blend with a fascia on the
surface of gluteus minimus. This fascia increases in thick-
ness and finally becomes the tendon of gluteus minimus at
its insertion into the capsule. The tendon then continues to
its insertion on a ridge lateral to the anterior triangular area
of the greater trochanter. The capsular insertion is irregular
and measures 10 to 15 mm mediolaterally and 20 to 25 mm
craniocaudally. The insertion on the greater trochanter
shows great variation between an irregular L-shape and a
triangular area on the greater trochanter (Fig. 4). The area
anterior and medial to the insertion may be covered with a
thin layer of fibrocartilage forming the bottom of a bursa
under the tendon of gluteus minimus.
The posterior fibres run in a dorsoventral direction to the
capsule and the anterior fibres in a craniocaudal direction.
They make an angle of approximately 75° with each other.
The anterior craniocaudal fibres follow an almost straight
course while the posterior fibres wind around the greater
trochanter. The relationship between the capsular and tro-
chanteric insertions changes during the arc of hip flexion.
In the neutral position, the posterior fibres alter their direc-
tion between 60° and 80° at the capsular insertion, whereas
the anterior fibres run straight. At 90° of flexion, all fibres
of muscle and tendon run straight from their origin to their
insertion on the trochanter.
There was a fan-shaped appearance to the musculature in
nine hips. In two, an accessory muscle was identified
arising directly from the lateral edge of the iliac crest
between the anterosuperior iliac spine and the iliac tuber-
cule and from the fascia covering gluteus minimus. Dist-
ally, it joined the tendon of gluteus minimus. The branch of
the superior gluteal nerve to the tensor fasciae latae passed
behind this muscle. Five specimens could not be classified
into either group; in these the muscle between the antero-
superior iliac spine and the iliac tubercle originated directly
from the lateral edge of the iliac crest, but was covered by
the fascia of gluteus minimus. As in the cases with the
accessory muscle, the nerve to tensor fasciae latae passed
behind these muscle fibres. In a subsequent dissection of
two specimens we found a sequential innervation of gluteus
minimus with four distinct branches coming from the supe-
rior gluteal nerve.
Muscle function. The model of gluteus minimus (Fig. 2)
allowed us to measure the excursion of the muscle in
standardised directions. On moving the hip from extension
to 100° of flexion in neutral rotation, sectors I and II
shortened, sector III remained unchanged and sector IV
elongated slightly (Fig. 5). With external rotation of the
extended hip, sector I elongated, sector II showed no
change in length of the muscle fibre and sectors III and IV
shortened. With internal rotation the entire muscle elongat-
ed increasingly from anterior to posterior (Fig. 6). With
internal rotation of the flexed hip, sectors I to III shortened
and sector IV showed no change in length. With external
rotation all the muscle fibres elongated (Fig. 7). Abduction
Fig. 3
Diagram of gluteus minimus showing the area of origin, excluding the
anteroinferior iliac spine and the reflected head of the rectus from inside
the pelvis at the greater sciatic notch.
Fig. 4
Diagram showing the differing areas of insertion of the tendon of gluteus
minimus on the greater trochanter.
caused increased shortening from sector IV to sector I, with
sector IV showing little change in length (Fig. 8).
Generally, the origin of gluteus minimus has been defined
as from the external iliac fossa between the anterior and
inferior gluteal lines.
Platzer, in Pernkopf s textbook of
describes an origin from inside the pelvis. At the
greater sciatic notch the caudal muscle fibres cover the
bone as they come round, protecting the superior gluteal
artery and nerve from damage.
The presence of an accessory muscle anterior to gluteus
minimus has been described
and variously termed ‘glu-
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Fig. 5
Excursion of the muscle fibres during hip flexion from
0° to 100°.
Fig. 6
Excursion of the muscle fibres in extension of the hip in
internal and external rotation.
Fig. 7
Excursion of the muscle fibres in 90° flexion of the hip
in internal and external rotation.
Fig. 8
Excursion of the muscle fibres at abduction.
teus quartus’ or ‘gluteus scansorius’. This specific pattern
was present in two out of our 16 dissections. The function
of this accessory muscle remains unclear. A strong variant
is found in monkeys and is thought to rotate the hip
internally enabling them to climb trees (scansorius from
scandere (Lat), to climb).
Correspondingly, we observed
that with increasing hip flexion the anterior part of gluteus
minimus has a stronger action for internal rotation.
The function of gluteus minimus and gluteus medius was
thought to be the same, that is primary abduction of the
We found that gluteus minimus acts as a flexor and
an abductor of the hip and also as either an internal or
external rotator, depending on which part of the muscle is
active and on the position of the femur relative to the pelvis
(Fig 5). This can be explained by the orientation of the
muscle fibres and the change of direction of the tendon
fibres at the joint capsule. The muscle fibres of sector I
elongate during external rotation and are therefore able to
resist this movement, which may help to prevent anterior
dislocation of the natural or prosthetic hip. During passive
internal rotation all muscle fibres elongate increasingly
from anterior to posterior and are therefore able to resist
internal rotation. This may help to prevent impingement of
the femoral neck against the superomedial acetabular rim
and posterior dislocation of a prosthetic hip. When the
entire muscle is activated simultaneously, which theoret-
ically is possible because of its sequential innervation, the
forces for internal and external rotation are counterba-
lanced. In such a situation the femoral head is pulled into
the acetabulum and stabilised.
In the flexed hip, the musculotendinous fibres run
straight from their origin to the femoral insertion. The
muscle fibres of sectors I to III rotate the hip internally,
whereas the posterior fibres are inactive. During passive
external rotation the entire muscle is stretched and is
therefore able to resist external rotation.
We conclude that one of the primary functions of gluteus
minimus is to stabilise the head of the femur in its socket.
This has already been suggested from electomyographic
and anatomical studies,
and more recently by an MRI
investigation of the abductors.
The stabilising action
seems to be more important in the extended hip, because of
the stronger counterbalancing activity of the muscle. Tight-
ening the joint capsule, a function which does not depend
on the position of the hip, also adds stability. Furthermore,
the tendon serves as a physical barrier against superolateral
migration of the head since it passes over it (Fig. 9). This
plays an important role in a hip which lacks geometrical
stability, for example a dysplastic joint in which the head
may sublux anterolaterally. A lateral flattening, or even
indentation, of the head can be observed in such cases,
especially in spastic hips.
The limitation of the model of gluteus minimus is that
only passive excursions of the muscle fibres are measured.
We attribute shortening to contraction and elongation to the
ability to resist movement. Our study cannot, however,
imitate the activation and co-ordination of the different
parts of the muscle in real life.
Recurrent dislocation after total hip arthroplasty has been
attributed to inadequate myofascial tension.
enhance stability, anterior and distal advancement of the
greater trochanter has been recommended to increase the
tension in gluteus medius and minimus.
The capacity
of a trochanteric osteotomy to prevent dislocation of the hip
by restoring the correct tension to the soft-tissue sleeve
may be improved by including the insertion of minimus to
the trochanter. Care should be taken to identify the insertion
of gluteus minimus during the approach to the hip and to
restore its anatomy at closure.
No benefits in any form have been received or will be received from a
commercial party related directly or indirectly to the subject of this
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Fig. 9
Diagram of the forces exerted by gluteus minimus on
the head of the femur, with one stabilising the counter-
balanced action of the anterior and posterior parts of
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... This is the first description regarding G. Med/Min and an interesting one since previously stronger gluteus maximus, the hip extensor, was regarded as the responsible muscle for pelvic retroversion [16]. The function of G. also as either an internal or external rotator [19]. Due to the complex and ever-changing function of both G.Med and G.Min, two speculations are proposed here to serve as possible explanations for how the G.Med and G.Min affect pelvic retroversion. ...
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Objective To quantify muscle characteristics (volumes and fat infiltration) and identify their relationship to sagittal malalignment and compensatory mechanism recruitment.Methods Female adult spinal deformity patients underwent T1-weighted MRI with a 2-point Dixon protocol from the proximal tibia up to the T12 vertebra. 3D reconstructions of 17 muscles, including extensors and flexors of spine, hip and knee, were obtained. Muscle volume standardized by bone volume and percentage of fat infiltration (Pfat) were calculated. Correlations and regressions were performed.ResultsA total of 22 patients were included. Significant correlations were observed between sagittal alignment and muscle parameters. Fat infiltration of the hip and knee flexors and extensors correlated with larger C7-S1 SVA. Smaller spinal flexor/extensor volumes correlated with greater PI-LL mismatch (r = − 0.45 and − 0.51). Linear regression identified volume of biceps femoris as only predictor for PT (R2 = 0.34, p = 0.005) and Pfat of gluteus minimus as only predictor for SVA (R2 = 0.45, p = 0.001). Sagittally malaligned patients with larger PT (26.8° vs. 17.2°) had significantly smaller volume and larger Pfat of gluteus medius, gluteus minimus and biceps femoris, but similar values for gluteus maximus, the hip extensor.Conclusion This study is the first to quantify the relationship between degeneration of spino-femoral muscles and sagittal malalignment. This pathoanatomical study identifies the close relationship between gluteal, hamstring muscles and PT, SVA, which deepens our understanding of the underlying etiology that contributes to adult spinal deformity.
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This study aimed to identify preoperative lower-limb muscle predictors for gait speed improvement after total hip arthroplasty (THA) with hip osteoarthritis. Gait speed improvement was evaluated as the subtraction of preoperative speed from postoperative speed. The preoperative muscle composition of ipsilateral hip abductors was evaluated using computed tomography. The females (n = 45) showed smaller total cross-sectional areas of the gluteal muscles than the males (n = 13). The gluteus maximus in the females showed lower lean muscle mass area (LMM) and higher ratios of the intramuscular fat area and the intramuscular adipose tissue area to the total muscle area (TM) than the males. Regression analysis revealed that LMM/TM of the glutei medius and minimus may correlate negatively with postoperative improvement in gait speed. Receiver operating characteristic curve analysis for prediction of minimum clinically important improvement in gait speed at ≥0.32 m/s resulted in the highest area under the curve for TM in the upper portion of the gluteus maximus with negative correlation. The explanatory variables of hip abductor muscle composition predicted gait speed improvement after THA more precisely in the females compared with the total group of both sexes. Preoperative muscle composition should be evaluated separately based on sex for the achievement of clinically important improvement in gait speed after THA.
Background: There is insufficient literature on multi-directional hip strength differences and dynamic balance between people with knee osteoarthritis (KOA) and healthy controls. Objective: In people with unilateral KOA, determine if hip/knee strength and dynamic balance differs (i) between sides, and (ii) compared to controls. Methods: Thirty-six participants (17 women; 65.5 ± 8.9 years) with unilateral KOA and 36 age- and sex-matched controls were included in a cross-sectional study. Outcomes included hip strength, quadriceps strength, and dynamic balance (three directions) during the Star Excursion Balance Test. Mixed ANOVA analysis was completed to investigate differences between Limbs and Groups. Mean differences (MD) and 95% confidence intervals (CI) were calculated. Results: Quadriceps and hip adduction strength were 16% (95%CI:10, 22) and 9% [95%CI: 3, 16) lower on the affected compared to non-affected side. Quadriceps and hip abduction, adduction, flexion, and extension strength (MD varying from 16%, 95%CI: 8, 25; to 34%, 95%CI: 17, 50) were weaker bilaterally in individuals with KOA compared to control. Posteromedial balance was 4% (95%CI: 2, 6) lower for affected compared to non-affected limbs in those with KOA and 13% (95%CI: 6, 21) lower in the affected limb compared to controls. Individuals with KOA had lower balance bilaterally in the anterior 11% (95%CI: 7, 15) and posterolateral 21% (95%CI: 13, 30) directions. Conclusion: Hip/knee strength (especially in the sagittal and frontal planes) and dynamic balance are lower bilaterally in people with KOA compared to controls. Hip adduction strength is lower on the affected than non-affected limbs of people with KOA. Clinicians should consider that knee extension strength, hip strength, and dynamic balance are lower bilaterally in people with unilateral KOA.
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Background Measures of hip muscle morphology and composition (e.g., muscle size and fatty infiltration) are possible with magnetic resonance imaging (MRI). Standardised protocols or guidelines do not exist for evaluation of hip muscle characteristics, hindering reliable and valid inter-study analysis. This scoping review aimed to collate and synthesise MRI methods for measuring lateral hip muscle size and fatty infiltration to inform the future development of standardised protocols. Methods Five electronic databases (Medline, CINAHL, Embase, SportsDISCUS and AMED) were searched. Healthy or musculoskeletal pain populations that used MRI to assess lateral hip muscle size and fatty infiltration were included. Lateral hip muscles of interest included tensor fascia late (TFL), gluteus maximus, gluteus medius, and gluteus minimus. Data on MRI parameters, axial slice location, muscle size and fatty infiltrate measures were collected and analysed. Cross referencing for anatomical locations were made between MRI axial slice and E-12 anatomical plastinate sections. Results From 2684 identified publications, 78 studies contributed data on volume ( n = 31), cross sectional area (CSA) ( n = 24), and fatty infiltration ( n = 40). Heterogeneity was observed for MRI parameters and anatomical boundaries scrutinizing hip muscle size and fatty infiltration. Seven single level axial slices were identified that provided consistent CSA measurement, including three for both gluteus maximus and TFL, and four for both gluteus medius and minimus. For assessment of fatty infiltration, six axial slice locations were identified including two for TFL, and four for each of the gluteal muscles. Conclusions Several consistent anatomical levels were identified for single axial MR slice to facilitate muscle size and fatty infiltration muscle measures at the hip, providing the basis for reliable and accurate data synthesis and improvements in the validity of future between studies analyses. This work establishes the platform for standardised methods for the MRI assessment of lateral hip musculature and will aid in the examination of musculoskeletal conditions around the hip joint. Further studies into whole muscle measures are required to further optimise methodological parameters for hip muscle assessment.
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The female pelvis morphology represents an evolved compensation between two opposing needs: a broad pelvis enough to deliver a sizeable brained offspring while remaining narrow enough to allow for effective bipedal gait. The precise expectation of hip abductor force generation is critical in anthropological studies and experimental practice of human stride mechanics. Hip implants and surgical procedures for hip anatomy reconstruction are based on the static single-leg stance paradigm. The current work investigated the impact of sexual dimorphism on the ground reaction force (GRF) acting on the mediolateral direction during level walking, emphasizing the difference in hip abductor muscle biomechanics and its correlation to ground reaction force moment arm, R. The ground reaction force in the mediolateral direction, hip abduction and adduction moments during the gait cycle and ground reaction force moment arm, R were measured. The current study concludes that the male individuals exhibit significantly higher mass-specific mediolateral ground reaction force during level walking. In contrast, hip abductor moments/kg body weight, medialization of the trochanter, R, and hip coronal were more significant in female individuals. We conclude that increased abductor moment and medialization of the greater trochanter will increase R, hip coronal and decrease abductor moment arm, r, in female individuals, affecting the effective mechanical advantage (EMA) of hip abductors in single-limb stance during level walking.
The aim of this study was to develop an automatic segmentation method for hip abductor muscles and find their fat fraction associations with early stage hip osteoarthritis (OA) cartilage degeneration biomarkers. This Institutional Review Board approved, Health Insurance Portability and Accountability Act compliant prospective study recruited 61 patients with evidence of hip OA or Femoroacetabular Impingement (FAI). Magnetic Resonance (MR) images were acquired for cartilage segmentation, T1ρ and T2 relaxation times computation and grading of cartilage lesion scores. A 3D V‐Net (Dice loss, Adam optimizer, learning rate=1e‐4, batch size=3) was trained to segment the 3 muscles (gluteus medius, gluteus minimus and tensor fascia latae). The V‐Net performance was measured using Dice, distance maps between manual and automatic masks, and Bland‐Altman plots of the fat fractions and volumes. Associations between muscle fat fraction and T1ρ, T2 relaxation times values were found using voxel based relaxometry (VBR). A p‐value<0.05 was considered significant. The V‐Net had a Dice of 0.90, 0.88 and 0.91 (GMed, GMin and TFL). The VBR results found associations of fat fraction of all three muscles in early stage OA and FAI patients with T1ρ, T2 relaxation times. Using an automatic, validated segmentation model, the associations derived between OA biomarkers and muscle fat fractions provide insight into early changes that occur in OA, and show that hip abductor muscle fat is associated with markers of cartilage degeneration. This article is protected by copyright. All rights reserved.
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Purpose Recent advances in diagnostic imaging techniques and soft tissue endoscopy now allow for precise diagnosis and management of extra-articular hip pathology. The aim of this scoping review is to present an evidence-based update of the relevant literature focussing only on the pathoanatomy, clinical assessment and the diagnosis of pathology in the peritrochanteric space. Methods A literature search was performed on PubMed to include articles which reported on the anatomy and diagnosis of greater trochanteric pain syndrome, trochanteric bursitis, gluteus medius tears and external snapping hip syndrome. Results A total of 542 studies were identified, of which 49 articles were included for full text analysis for the scoping review. Peritrochanteric space pathology can be broadly classified into (1) greater trochanteric pain syndrome (GTPS), (2) abductor tears and (3) external snapping hip syndrome. Anatomically, gluteus medius, gluteus minimus and tensor fascia lata work in conjunction to abduct and internally rotate the hip. The anterolateral part of the gluteus medius tendon is more prone to tears due to a thin tendinous portion. Increased acetabular anteversion has also been shown to be associated with gluteal and trochanteric bursitis. In terms of clinical examination, tests which were found to be most useful for assisting in the diagnoses of lateral hip pain were the single-leg stance, resisted external derotation of the hip, hip lag sign and the Trendelenburg’s test. Dynamic ultrasound along with guided injections and MRI scan do assist in differentiating the pathology and confirming the diagnosis in patients presenting with lateral hip pain. Finally, the assessment of baseline psychological impairment is essential in this group of patients to ensure outcomes are optimised. Conclusion Lateral hip pain used to be a poorly defined entity, but advances in imaging and interest in sports medicine have led to a better understanding of the pathology, presentation and management of this cohort of patients. A thorough appreciation of the anatomy of the abductor musculature, specific clinical signs and imaging findings will lead to an appropriate diagnosis being made and management plan instituted. Level of evidence IV.
Objective: The purpose of this study was to evaluate an association between fall-related intertrochanteric or femoral neck fractures and gluteus medius and minimus atrophy, furthermore, to find a correlation of whether any difference between femoral neck or intertrochanteric fracture and degree of muscle atrophy Materials and Methods: A retrospective review of 230 patients with intertrochanteric or femoral neck fracture, aged > 65 years, and 60 age- matched controls was performed. We assessed gluteus medius and minimus atrophy and calculated the cross-sectional area (CSA) and ratio of lean muscle to adipose infiltration (M/A ratio) for each muscle. Results: The atrophy scores for the g.medius and g.minimus muscles on the fractured side were significantly higher than scores on the healthy side and scores in the control group. The atrophy scores for the g.medius on the healthy side were not significantly different from scores in the control group. The atrophy scores for g.medius were significantly different between the fractured side and the healthy side for all ages, the atrophy scores for g.minimus was significantly different in the patients aged over 75. There was no significant difference in the following parameters between the fractured side and healthy side of the patients aged 65 - 75 years; the atrophy score, CSA and M/A ratio. The patients have a lower CSA and M/A ratio on the fractured side than on the healthy side and lower CSA and M/A ratio than in the control group. However, there were no significant differences in the M/A ratio between the healthy side and the control group. CSA was not significantly different between the fractured side and healthy side in the male patients and in the patients with lower BMI (<30). There was no significant difference in the atrophy scores between subjects with intertrochanteric versus femoral neck fractures, the CSAs of the g.medius and g.minimus were significantly different between the intertrochanteric fracture and femoral neck fracture groups. Conclusions: The fractured sides showed greater g.medius and g.minimus muscle atrophy, which may be a predictor of fall-related hip fractures in the elderly. Gluteal muscle volume may be associated with proximal femur fracture subtype.
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Gluteus medius and minimus tears have recently been reported to be very common and the main etiology of lateral sided hip pain. The purpose of this study was to determine whether there is any correlation between the dimensions of the tendon insertions and bare areas (BA) and various bony landmarks. Twenty-seven hemipelvises from adult male hips were included. The bony landmarks [anterior tip (Ta), posterior tip of trochanter, vastus tubercle (VT) and center of BA] were marked. The longitudinal lengths and widths (maximum) of posterosuperior (PS), lateral facets (LF), minimus insertion (Min) and BA and the distance between posterior (Tp) and Ta and between anterior/posterior tips and the VT or center of BA were measured using a digital caliper. A correlation analysis was performed between variables. There was a correlation between LFlength and Minlength (r = 0.4, P = 0.01) and between Ta–BA and PS + LF (r = 0.5, P = 0.003) or Minlength (r = 0.4, P = 0.016). LFwidth was negatively correlated with BAwidth (r = −0.4, P = 0.002). Tp–BA was negatively correlated with BAwidth (r = −0.4, P = 0.01). LFwidth was correlated with Tp–BA, and this nearly reached statistical significance (r = 0.3, P = 0.05). BA can be used intraoperatively as landmarks to estimate the width of the LF and also to determine the length of the longitudinal insertion of the gluteus medius and minimus tendons.
The hip abductor muscles are considered important for gait and biomechanics of the hip joint; however, their specific function has not been defined precisely. The intensity of magnetic resonance imaging signals in skeletal muscle has been reported to increase immediately after exercise. Making use of this phenomenon, we evaluated the hip abductor muscles. Magnetic resonance imaging was performed after isometric exercise of the hip abductor in three positions (20 degrees of abduction, neutral, and 20 degrees of adduction). The abduction force of the hip was measured with a dynamometer, and electromyographic measurements were made simultaneously for the same hip positions. Additionally, magnetic resonance imaging was performed after one-legged stance. As the hip was more adducted, the signal intensity increased on the scans. The values for muscle force, as evaluated with the dynamometer and integrated electromyography, also supported the results. The increase in signal intensity of the gluteus minimus at 20 degrees of abduction and after one-legged stance was significantly greater than that of the gluteus medius (p < 0.0001 and p < 0.0001, respectively). The results of this study indicate that the gluteus minimus muscle, along with the gluteus medius, plays an important role in hip abduction, gait, and stabilization of the pelvis.
Among the complications in a series of 1,400 consecutive Charnley low friction arthroplasty procedures, there were 8 dislocations, and 3 highly unstable hips. Three dislocations followed severe trauma, in 2 of the 3 there was only fibrous union of the greater trochanter. In all but 2 of the hips, more than one previous operation had been performed. More than one technical fault was evident in most dislocations. Six of the 8 dislocations required reoperation. Meticulous attention to the Charnley procedure, including soft tissue elements of the hip joint is necessary to avoid instability and dislocation following total hip arthroplasty.
The transgluteal approach to the hip, first described by Bauer et al. in 1979, has since become a recognized routine method. Its longitudinal incision of the fibers of the gluteus medius and minimus and the vastus lateralis muscles takes advantage of the tendinous junction of these muscles over the greater trochanter. This paper describes the modifications of the transgluteal approach described in the literature and compares them to the original procedure. In 52 hip specimens, including attached muscles, the insertions and different variations of the junction of the gluteus medius, minimus and vastus lateralis muscles over the greater trochanter are described and statistically analysed. In 59.6% of all specimens there proved to be a united tendinous junction of all the muscles referred to above, while in 40.4% autonomous insertions of the gluteus medius and/or gluteus minimus were seen. In accordance with the anatomical results, the form of incision described by the original authors can be considered the most favourable. In roughly one-third of all hip operations, autonomous insertions of gluteus medius and minimus must be taken into account, since otherwise total or partial upward displacement of the autonomous muscle insertions could occur.
The more accurate description of the anatomy of the glutei and the new biomechanical theory that has been presented describe the abductor mechanism as a system in which the tensor fasciae latae has the primary function of balancing the weight of the body and the non-weight-bearing leg during walking. Gluteus medius with its three parts and phasic functions is responsible for the stabilisation of the hip joint in the initial phase of the gait cycle. It is important also in initiating the major gait determinant of pelvic rotation. Gluteus minimus functions as a primary hip stabiliser during the mid- and late phase of the gait cycle.
In order to define the technical modalities of the so-called transgluteal approach to the hip, the authors studied the structure and topography of the anatomic features encountered in this approach. The gluteus medius, gluteus minimus and vastus lateralis muscles are anatomically continuous by way of their tendinous fibers. The gluteus minimus muscle winds over the cranial and then anterolateral aspect of the capsule, to which it is bound by fibrous tracts and tendinous expansions; its terminal tendon blends its fibers with the anterior part of the tendon of the gluteus medius and enters into continuity with the superficial tendinous fibers of the anterior part of the vastus lateralis. The zone of junction of the three muscle structures is closely bound to the anterior aspect of greater trochanter. The caudal neurovascular trunk of the space between the gluteus medius and vastus lateralis is situated at a distance of 3 to 5 cm from the greater trochanter. The practical surgical implications are discussed, particularly as regards the methods of dissecting the anterior margin of the transgluteal incision, exposure of the capsule and preservation of the neurovascular pedicle, with reference to concepts published previously in studies elsewhere.
We evaluated 38 noninstitutionalized patients with spastic quadriplegic cerebral palsy with 51 dislocated hips. Nine hips had been reduced. The mean follow-up was 18 years, with an average age of 26 years. At follow-up, four were ambulatory with aids. Patients who could walk had normal intelligence and a level pelvis. In patients with 18 unreduced unilateral hip dislocations, pelvic obliquity and scoliosis were present in 12. In seven patients with reduced unilateral hip dislocations, similar findings were present in only two patients. Half of the dislocated hips were painful. Based on these findings, we recommend reduction of unilateral dislocations. Bilateral dislocations may benefit from reduction if treatment is undertaken before significant adaptive deformity of the femoral head occurs.
Twenty-one patients had trochanteric advancement after experiencing an average of 3.9 dislocations in a mean period of 46 weeks following total hip arthroplasty. Before trochanteric advancement was performed, component malposition and mechanical impingement were excluded as causes of dislocation. Radiographic measurements revealed that the trochanter was advanced an average of 16 +/- 7.7 mm (1 SD). Four patients, all with rheumatoid arthritis, had trochanteric migration greater than 1 cm. Seventeen of the 21 hips had no further dislocations following trochanteric advancement, with mean follow-up period of 2.7 years. Two patients dislocated because of extremes in hip position and had no further dislocations. Two patients dislocated who had trochanteric migration greater than 1 cm. Only one patients with a technically satisfactory trochanteric advancement continued to dislocate repeatedly. In patients without component malposition or obvious sources of impingement, trochanteric advancement is an effective and safe procedure for prevention of recurrent dislocations after total hip arthroplasty.
1. Of 1013 hospitalized patients with cerebral palsy, 274 patients with dislocated or subluxated hips have been studied, a prevalence of 28 per cent. This figure is high because severely involved, neurologically and developmentally immature quadriplegic patients constituted a large fraction of the hospital population. 2. The mean age at which dislocation occurred in 139 of these patients was seven years. 3. It is proposed that retained neonatal reflexes, muscle imbalance and contracture, coxa valga, femoral anteversion, and acetabular index are responsible for the dislocations. 4. The results and complications of the 518 combined operations are summarized. 5. Correction of coxa valga and of femoral anteversion are the most important surgical considerations in the prevention and treatment of dislocation of the hip in cerebral palsy.