Aims. Femoroacetabular impingement (FAI) patients report exacerbation of hip pain in deep flexion. However, the exact impingement location in deep flexion is unknown. The aim was to investigate impingement-free maximal flexion, impingement location, and if cam deformity causes hip impingement in flexion in
Aims. The effect of pelvic tilt (PT) and sagittal balance in hips with pincer-type femoroacetabular impingement (FAI) with acetabular retroversion (AR) is controversial. It is unclear if patients with AR have a rotational abnormality of the iliac wing. Therefore, we asked: are parameters for sagittal balance, and is rotation of the iliac wing, different in patients with AR compared to a control group?; and is there a correlation between iliac rotation and acetabular version?. Methods. A retrospective, review board-approved, controlled study was performed including 120 hips in 86 consecutive patients with symptomatic
Femoroacetabular impingement (FAI) causes pain
and chondrolabral damage via mechanical overload during movement
of the hip. It is caused by many different types of pathoanatomy,
including the cam ‘bump’, decreased head–neck offset, acetabular
retroversion, global acetabular overcoverage, prominent anterior–inferior
iliac spine, slipped capital femoral epiphysis, and the sequelae
of childhood Perthes’ disease. Both evolutionary and developmental factors may cause
Aims. What represents clinically significant acetabular undercoverage
in patients with symptomatic cam-type femoroacetabular impingement
(FAI) remains controversial. The aim of this study was to examine
the influence of the degree of acetabular coverage on the functional
outcome of patients treated arthroscopically for cam-type
Advanced MRI cartilage imaging such as T. 1. -rho
(T1ρ) for the diagnosis of early cartilage degradation prior to morpholgic
radiological changes may provide prognostic information in the management
of joint disease. This study aimed first to determine the normal
T1ρ profile of cartilage within the hip, and secondly to identify
any differences in T1ρ profile between the normal and symptomatic
femoroacetabular impingement (FAI) hip. Ten patients with cam-type
FAI (seven male and three female, mean age 35.9 years (28 to 48))
and ten control patients (four male and six female, mean age 30.6
years (22 to 35)) underwent 1.5T T1ρ MRI of a single hip. Mean T1ρ relaxation
times for full thickness and each of the three equal cartilage thickness
layers were calculated and compared between the groups. The mean
T1ρ relaxation times for full cartilage thickness of control and
FAI hips were similar (37.17 ms (. sd. 9.95) and 36.71 ms
(. sd. 6.72), respectively). The control group demonstrated
a T1ρ value trend, increasing from deep to superficial cartilage
layers, with the middle third having significantly greater T1ρ relaxation
values than the deepest third (p = 0.008). The
The purpose of this study was to determine patient-reported
outcomes of patients with mild to moderate developmental dysplasia
of the hip (DDH) and femoroacetabular impingement (FAI) undergoing
arthroscopy of the hip in the treatment of chondrolabral pathology.
A total of 28 patients with a centre-edge angle between 15° and
19° were identified from an institutional database. Their mean age
was 34 years (18 to 53), with 12 female and 16 male patients. All
underwent labral treatment and concomitant correction of
In Japan, osteoarthritis (OA) of the hip secondary
to acetabular dysplasia is very common, and there are few data concerning
the pathogeneses and incidence of femoroacetabular impingement (FAI).
We have attempted to clarify the radiological prevalence of painful
FAI in a cohort of Japanese patients and to investigate the radiological findings.
We identified 176 symptomatic patients (202 hips) with Tönnis grade
0 or 1 osteoarthritis, whom we prospectively studied between August
2011 and July 2012. There were 61 men (65 hips) and 115 women (137
hips) with a mean age of 51.8 years (11 to 83). Radiological analyses
included the α-angle, centre–edge angle, cross-over sign, pistol
grip deformity and femoral head neck ratio. Of the 202 hips, 79
(39.1%) had acetabular dysplasia, while 80 hips (39.6%) had no known
aetiology. We found evidence of
Aims. Recently, there has been considerable interest in quantifying
the associations between bony abnormalities around and in the hip
joint and osteoarthritis (OA). Our aim was to investigate the relationships
between acetabular undercoverage, acetabular overcoverage, and femoroacetabular
impingement (FAI) with OA of the hip, which currently remain controversial. . Materials and Methods. A total of 545 cadaveric skeletons (1090 hips) from the Hamann-Todd
osteological collection were obtained. Femoral head volume (FHV),
acetabular volume (AV), the FHV/AV ratio, acetabular version, alpha
angle and anterior femoral neck offset (AFNO) were measured. A validated
grading system was used to quantify OA of the hip as minimal, moderate,
or severe. Multiple linear and multinomial logistic regression were
used to determine the factors that correlated independently with
the FHV, AV, and the FHV/AV ratio. . Results. Female cadavers had smaller FHVs (standardised beta -0.382, p
<
0.001), and AVs (standardised beta -0.351, p <
0.001), compared
with male patients, although the FHV/AV ratio was unchanged. Every
1° increase in alpha angle increased the probability of having moderate
OA of the hip compared with minimal OA by 7.1%. Every 1 mm decrease
in AFNO increased the probability of having severe or moderate OA
of the hip, compared with minimal OA, by 11% and 9%, respectively.
The relative risk ratios of having severe OA of the hip compared
with minimal OA were 7.2 and 3.3 times greater for acetabular undercoverage
and overcoverage, respectively, relative to normal acetabular cover. . Conclusion . Acetabular undercoverage and overcoverage were independent predictors
of increased OA of the hip. The alpha angle and AFNO had modest
effects, supporting the hypothesis that bony abnormalities both
in acetabular dysplasia and
We investigated the development of CT-based bony
radiological parameters associated with femoroacetabular impingement
(FAI) in a paediatric and adolescent population with no known orthopaedic
hip complaints. We retrospectively reformatted and reoriented
225 abdominal CTs into standardised CT pelvic images with neutral
pelvic tilt and inclination (244 female and 206 male hips) in patients
ranging from two to 19 years of age (mean 10.4 years). The Tönnis
angle, acetabular depth ratio, lateral centre–edge angle, acetabular
version and α-angle were assessed. Acetabular measurements demonstrated increased acetabular coverage
with age and/or progressive ossification of the acetabulum. The α-angle
decreased with age and/or progressive cortical bone development
and resultant narrowing of the femoral neck. Cam and pincer morphology
occurred as early as ten and 12 years of age, respectively, and
their prevalence in the adolescent patient population is similar
to that reported in the adult literature. Future aetiological studies
of
There is an increased risk of fracture following
osteoplasty of the femoral neck for cam-type femoroacetabular impingement
(FAI). Resection of up to 30% of the anterolateral head–neck junction
has previously been considered to be safe, however, iatrogenic fractures
have been reported with resections within these limits. We re-evaluated
the amount of safe resection at the anterolateral femoral head–neck
junction using a biomechanically consistent model. In total, 28 composite bones were studied in four groups: control,
10% resection, 20% resection and 30% resection. An axial load was
applied to the adducted and flexed femur. Peak load, deflection
at time of fracture and energy to fracture were assessed using comparison
groups. There was a marked difference in the mean peak load to fracture
between the control group and the 10% resection group (p <
0.001).
The control group also tolerated significantly more deflection before
failure (p <
0.04). The mean peak load (p = 0.172), deflection
(p = 0.547), and energy to fracture (p = 0.306) did not differ significantly between
the 10%, 20%, and 30% resection groups. . Any resection of the anterolateral quadrant of the femoral head–neck
junction for
We report the clinical and radiological outcome
of subcapital osteotomy of the femoral neck in the management of symptomatic
femoroacetabular impingement (FAI) resulting from a healed slipped
capital femoral epiphysis (SCFE). We believe this is only the second
such study in the literature. . We studied eight patients (eight hips) with symptomatic
We examined the relationship between the size
of the femoral cam in femoroacetabular impingement (FAI) and acetabular
pathomorphology to establish if pincer impingement exists in patients
with a femoral cam. CT scans of 37 symptomatic impinging hips with a femoral cam
were analysed in a three-dimensional study and were compared with
34 normal hips. The inclination and version of the acetabulum as
well as the acetabular rim angle and the bony acetabular coverage
were calculated. These measurements were correlated with the size
and shape of the femoral cams. While the size of the femoral cam varied characteristically,
the acetabular morphology of the two groups was similar in terms
of version (normal mean 23° (. sd. 7°); cam mean 22° (. sd. 9°)),
inclination (normal mean 57° (. sd. 5°); cam mean 56° (. sd. 5°)),
acetabular coverage (normal mean 41% (. sd. 5%); cam mean
42% (. sd. 4%)) and the mean acetabular rim angle (normal
mean 82° (. sd. 5°); cam mean 83° (. sd. 4°)). We found no correlation between acetabular morphology and the
severity of cam lesion and no evidence of either global or focal
over-coverage to support the diagnosis of ‘mixed’
Asphericity of the femoral head-neck junction is common in cam-type
femoroacetabular impingement (FAI) and usually quantified using
the alpha angle on radiographs or MRI. The aim of this study was
to determine the natural alpha angle in a large cohort of patients
by continuous circumferential analysis with CT. CT scans of 1312 femurs of 656 patients were analyzed in this
cross-sectional study. There were 362 men and 294 women. Their mean
age was 61.2 years (18 to 93). All scans had been performed for
reasons other than hip disease. Digital circumferential analysis
allowed continuous determination of the alpha angle around the entire
head-neck junction. All statistical tests were conducted two-sided;
a p-value < 0.05 was considered statistically significant.Aims
Methods
Aims. The frequency of severe femoral retroversion is unclear in patients with femoroacetabular impingement (FAI). This study aimed to investigate mean femoral version (FV), the frequency of absolute femoral retroversion, and the combination of decreased FV and acetabular retroversion (AR) in symptomatic patients with
The technical advances in arthroscopic surgery
of the hip, including the improved ability to manage the capsule
and gain extensile exposure, have been paralleled by a growth in
the number of conditions that can be addressed. This expanding list
includes symptomatic labral tears, chondral lesions, injuries of
the ligamentum teres, femoroacetabular impingement (FAI), capsular
laxity and instability, and various extra-articular disorders, including snapping
hip syndromes. With a careful diagnostic evaluation and technical
execution of well-indicated procedures, arthroscopic surgery of
the hip can achieve successful clinical outcomes, with predictable
improvements in function and pre-injury levels of physical activity
for many patients. This paper reviews the current position in relation to the use
of arthroscopy in the treatment of disorders of the hip. Cite this article:
Over recent years hip arthroscopic surgery has
evolved into one of the most rapidly expanding fields in orthopaedic surgery.
Complications are largely transient and incidences between 0.5%
and 6.4% have been reported. However, major complications can and
do occur. This article analyses the reported complications and makes recommendations
based on the literature review and personal experience on how to
minimise them.
Aims. Hip arthroscopy (HA) has become the treatment of choice for femoroacetabular impingement (FAI). However, less favourable outcomes following arthroscopic surgery are expected in patients with severe chondral lesions. The aim of this study was to assess the outcomes of HA in patients with
Aims. The purpose of this study was to evaluate spinopelvic mechanics from standing and sitting positions in subjects with and without femoroacetabular impingement (FAI). We hypothesize that
Aims. Abnormal femoral torsion (FT) is increasingly recognized as an additional cause for femoroacetabular impingement (FAI). It is unknown if in-toeing of the foot is a specific diagnostic sign for increased FT in patients with symptomatic
Aims. Hip arthroscopy has gained prominence as a primary surgical intervention for symptomatic femoroacetabular impingement (FAI). This study aimed to identify radiological features, and their combinations, that predict the outcome of hip arthroscopy for
Aims. The primary aim of this study was to determine the ten-year outcome following surgical treatment for femoroacetabular impingement (FAI). We assessed whether the evolution of practice from open to arthroscopic techniques influenced outcomes and tested whether any patient, radiological, or surgical factors were associated with outcome. Methods. Prospectively collected data of a consecutive single-surgeon cohort, operated for
Aims. The prevalence of combined abnormalities of femoral torsion (FT) and tibial torsion (TT) is unknown in patients with femoroacetabular impingement (FAI) and hip dysplasia. This study aimed to determine the prevalence of combined abnormalities of FT and TT, and which subgroups are associated with combined abnormalities of FT and TT. Methods. We retrospectively evaluated symptomatic patients with
Young adults with hip pain secondary to femoroacetabular
impingement (FAI) are rapidly being recognised as an important cohort
of orthopaedic patients. Interest in
Outcomes following different types of surgical intervention for femoroacetabular impingement (FAI) are well reported individually but comparative data are deficient. The purpose of this study was to conduct a systematic review (SR) and meta-analysis to analyze the outcomes following surgical management of
Aims. Femoroacetabular impingement (FAI) has been highlighted and well
documented primarily in Western countries and there are few large
studies focused on FAI-related morphological assessment in Asian
patients. We chose to investigate this subject. Patients and Methods. We assessed the morphology of the hip and the prevalence of radiographic
FAI in Japanese patients by measuring predictors of
In many papers, the diagnosis of pincer-type
femoroacetabular impingement (FAI) is attributed to the presence
of coxa profunda. However, little is known about the prevalence
of coxa profunda in the general population and its clinical relevance. In order to ascertain its prevalence in asymptomatic subjects
and whether it is a reliable indicator of pincer-type
We investigated differences in the location and
mode of labral tears between dysplastic hips and hips with femoroacetabular
impingement (FAI). We also investigated the relationship between
labral tear and adjacent cartilage damage. We retrospectively studied
72 symptomatic hips (in 68 patients: 19 men and 49 women) with radiological
evidence of dysplasia or
Objectives. The number of surgical procedures performed each year to treat
femoroacetabular impingement (FAI) continues to rise. Although there
is evidence that surgery can improve symptoms in the short-term,
there is no evidence that it slows the development of osteoarthritis
(OA). We performed a feasibility study to determine whether patient
and surgeon opinion was permissive for a Randomised Controlled Trial
(RCT) comparing operative with non-operative treatment for
Femoroacetabular impingement (FAI) is commonly
associated with early hip arthritis. We reviewed our series of 1300
hip resurfacing procedures. More than 90% of our male patients,
with an average age of 53 years, had cam impingement lesions. In
this condition, there are anterior femoral neck osteophytes, and
a retroverted femoral head on a normally anteverted neck. It is
postulated that
Aims. Femoroacetabular Junction Impingement (FAI) describes abnormalities
in the shape of the femoral head–neck junction, or abnormalities
in the orientation of the acetabulum. In the short term,
Slipped capital femoral epiphysis (SCFE) is relatively
common in adolescents and results in a complex deformity of the
hip that can lead to femoroacetabular impingement (FAI).
Aims. Responsiveness and ceiling effects are key properties of an outcome score. No such data have been reported for the original English version of the International Hip Outcome Tool 12 (iHOT-12) at a follow-up of more than four months. The aim of this study was to identify the responsiveness and ceiling effects of the English version iHOT-12 in a series of patients undergoing hip arthroscopy for intra-articular hip pathology at a minimum of one year postoperatively. Methods. A total of 171 consecutive patients undergoing hip arthroscopy with a diagnosis of femoroacetabular impingement (FAI) under the care of a single surgeon between January 2013 and March 2017 were included. iHOT-12 and EuroQol 5D-5L (EQ-5D-5L) scores were available pre- and postoperatively. Effect size and ceiling effects for the iHOT-12 were calculated with subgroup analysis. Results. A total of 122 patients (71.3%) completed postoperative PROMs scores with median follow-up of 24.3 months (interquartile range (IQR) 17.2 to 33.5). The median total cohort iHOT-12 score improved significantly from 31.0 (IQR 20 to 58) preoperatively to 72.5 (IQR 47 to 90) postoperatively (p < 0.001). The effect size (Cohen’s d) was 1.59. In all, 33 patients (27%) scored within ten points (10%) of the maximum score and 38 patients (31.1%) scored within the previously reported minimal clinically important difference (MCID) of the maximum score. Furthermore, nine (47%) male patients aged < 30 years scored within 10% of the maximum score and ten (53%) scored within the previously reported MCID of the maximum score. Conclusion. There is a previously unreported ceiling effect of the iHOT-12 at a minimum one-year follow-up which is particularly marked in young, male patients following hip arthroscopy for
Slipped capital femoral epiphysis (SCFE) may
lead to symptomatic femoroacetabular impingement (FAI). We report our
experience of arthroscopic treatment, including osteochondroplasty,
for the sequelae of SCFE. . Data were prospectively collected on patients undergoing arthroscopy
of the hip for the sequelae of SCFE between March 2007 and February
2013, including demographic data, radiological assessment of the
deformity and other factors that may influence outcome, such as
the presence of established avascular necrosis. Patients completed
the modified Harris hip score (mHHS) and the non-arthritic hip score
(NAHS) before and after surgery. . In total, 18 patients with a mean age of 19 years (13 to 42),
were included in the study. All patients presented with pain in
the hip and mechanical symptoms, and had evidence of
Orthopaedic surgeons have accepted various radiological
signs to be representative of acetabular retroversion, which is
the main characteristic of focal over-coverage in patients with
femoroacetabular impingement (FAI). Using a validated method for
radiological analysis, we assessed the relevance of these signs
to predict intra-articular lesions in 93 patients undergoing surgery
for
Slipped upper femoral epiphysis (SUFE) is one
of the known causes of cam-type femoroacetabular impingement (FAI).
The aim of this study was to determine the proportion of
Aims. Psychological factors play a critical role in patient presentation, satisfaction, and outcomes. Pain catastrophizing, anxiety, and depression are important to consider, as they are associated with poorer outcomes and are potentially modifiable. The aim of this study was to assess the level of pain catastrophizing, anxiety, and depression in patients with a range of hip pathology and to evaluate their relationship with patient-reported psychosocial and functional outcome measures. Patients and Methods. Patients presenting to a tertiary-centre specialist hip clinic were prospectively evaluated for outcomes of pain catastrophizing, anxiety, and depression. Validated assessments were undertaken such as: the Pain Catastrophizing Scale (PCS), the Hospital Anxiety Depression Scale (HADS), and the 12-Item Short-Form Health Survey (SF-12). Patient characteristics and demographics were also recorded. Multiple linear regression modelling, with adaptive least absolute shrinkage and selection operator (LASSO) variable selection, was used for analysis. Results. A total of 328 patients were identified for inclusion, with diagnoses of hip dysplasia (DDH; n = 50), femoroacetabular impingement (FAI; n = 55), lateral trochanteric pain syndrome (LTP; n = 23), hip osteoarthrosis (OA; n = 184), and avascular necrosis of the hip (AVN; n = 16) with a mean age of 31.0 years (14 to 65), 38.5 years (18 to 64), 63.7 years (20 to 78), 63.5 years (18 to 91), and 39.4 years (18 to 71), respectively. The percentage of patients with abnormal levels of pain catastrophizing, anxiety, or depression was: 22.0%, 16.0%, and 12.0% for DDH, respectively; 9.1%, 10.9%, and 7.3% for
Aims. This study sought to establish the prevalence of the cross over
sign (COS) and posterior wall sign (PWS) in relation to the anterior
pelvic plane (APP) in an asymptomatic population through reliable
and accurate 3D-CT based assessment. Materials and Methods. Data from pelvic CT scans of 100 asymptomatic subjects (200 hips)
undertaken for conditions unrelated to disorders of the hip were
available for analysis in this study. A previously established 3D
analysis method was applied to assess the prevalence of the COS
and PWS in relation to the APP. Results. Of the 200 included hips, 24% (48) presented a positive COS and
5.5% (11) presented a positive PWS. A combination of COS and PWS
was observed in 1% (two) of all hips (1%). . Conclusion. The high incidence of acetabular retroversion, determined by
the COS, shows that this anatomic configuration may not differ in
frequency between asymptomatic individuals and patients with symptomatic
femoroacetabular impingement (FAI). Patients presenting with hip pain and evidence of
Objectives. The purpose of this study was to evaluate the existing literature from 2005 to 2016 reporting on the efficacy of surgical management of patients with femoroacetabular impingement (FAI) secondary to slipped capital femoral epiphysis (SCFE). Methods. The electronic databases MEDLINE, EMBASE, and PubMed were searched and screened in duplicate. Data such as patient demographics, surgical technique, surgical outcomes and complications were retrieved from eligible studies. Results. Fifteen eligible level IV studies were included in this review comprising 261 patients (266 hips). Treatment groups included arthroscopic osteochondroplasty, surgical hip dislocation, and traditional open osteotomy. The mean alpha angle corrections were 32.14° (standard deviation (. sd). 7.02°), 41.45° (. sd. 10.5°) and 6.0° (. sd. 5.21°), for arthroscopy, surgical hip dislocation, and open osteotomy groups, respectively (p < 0.05). Each group demonstrated satisfactory clinical outcomes across their respective scoring systems. Major complication rates were 1.6%, 10.7%, and 6.7%, for arthroscopy, surgical dislocation and osteotomy treatments, respectively. Conclusion. In the context of SCFE-related
Aims. The aim of this study was to examine the real time in
vivo kinematics of the hip in patients with cam-type femoroacetabular
impingement (FAI). Patients and Methods. A total of 50 patients (83 hips) underwent 4D dynamic CT scanning
of the hip, producing real time osseous models of the pelvis and
femur being moved through flexion, adduction, and internal rotation.
The location and size of the cam deformity and its relationship
to the angle of flexion of the hip and pelvic tilt, and the position
of impingement were recorded. Results. In these patients with cam-type
To evaluate how abnormal proximal femoral anatomy affects different femoral version measurements in young patients with hip pain. First, femoral version was measured in 50 hips of symptomatic consecutively selected patients with hip pain (mean age 20 years (SD 6), 60% (n = 25) females) on preoperative CT scans using different measurement methods: Lee et al, Reikerås et al, Tomczak et al, and Murphy et al. Neck-shaft angle (NSA) and α angle were measured on coronal and radial CT images. Second, CT scans from three patients with femoral retroversion, normal femoral version, and anteversion were used to create 3D femur models, which were manipulated to generate models with different NSAs and different cam lesions, resulting in eight models per patient. Femoral version measurements were repeated on manipulated femora.Aims
Methods
Hyaline cartilage has a low capacity for regeneration. Untreated osteochondral lesions of the femoral head can lead to progressive and symptomatic osteoarthritis of the hip. The purpose of this study is to analyze the clinical and radiological long-term outcome of patients treated with osteochondral autograft transfer. To our knowledge, this study represents a series of osteochondral autograft transfer of the hip with the longest follow-up. We retrospectively evaluated 11 hips in 11 patients who underwent osteochondral autograft transfer in our institution between 1996 and 2012. The mean age at the time of surgery was 28.6 years (8 to 45). Outcome measurement included standardized scores and conventional radiographs. Kaplan-Meier survival curve was used to determine the failure of the procedures, with conversion to total hip arthroplasty (THA) defined as the endpoint.Aims
Methods
The aim of this study is to evaluate whether acetabular retroversion (AR) represents a structural anatomical abnormality of the pelvis or is a functional phenomenon of pelvic positioning in the sagittal plane, and to what extent the changes that result from patient-specific functional position affect the extent of AR. A comparative radiological study of 19 patients (38 hips) with AR were compared with a control group of 30 asymptomatic patients (60 hips). CT scans were corrected for rotation in the axial and coronal planes, and the sagittal plane was then aligned to the anterior pelvic plane. External rotation of the hemipelvis was assessed using the superior iliac wing and inferior iliac wing angles as well as quadrilateral plate angles, and correlated with cranial and central acetabular version. Sagittal anatomical parameters were also measured and correlated to version measurements. In 12 AR patients (24 hips), the axial measurements were repeated after matching sagittal pelvic rotation with standing and supine anteroposterior radiographs.Aims
Methods
Young adults undergoing total hip arthroplasty (THA) largely have different indications for surgery, preoperative function, and postoperative goals compared to a standard patient group. The aim of our study was to describe young adult THA preoperative function and quality of life, and to assess postoperative satisfaction and compare this with functional outcome measures. A retrospective cohort analysis of young adults (aged < 50 years) undergoing THA between May 2018 and May 2023 in a single tertiary centre was undertaken. Median follow-up was 31 months (12 to 61). Oxford Hip Score (OHS) and focus group-designed questionnaires were distributed. Searches identified 244 cases in 225 patients. Those aged aged under 30 years represented 22.7% of the cohort. Developmental dysplasia of the hip (50; 45.5%) and Perthes’ disease (15; 13.6%) were the commonest indications for THA.Aims
Methods
The benefit of arthroscopy of the hip in the
treatment of femoroacetabular impingement (FAI) in terms of quality
of life (QoL) has not been reported. We prospectively collected
data on 612 patients (257 women (42%) and 355 men (58%)) with a
mean age at the time of surgery of 36.7 years (14 to 75) who underwent
arthroscopy of the hip for
This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement.Aims
Methods
Pelvic incidence (PI) is considered an important anatomical parameter for determining the sagittal balance of the spine. The contribution of an abnormal PI to hip osteoarthritis (OA) remains controversial. In this study, we aimed to investigate the relationship between PI and hip OA, and the difference in PI between hip OA without anatomical abnormalities (primary OA) and hip OA with developmental dysplasia of the hip (DDH-OA). In this study, 100 patients each of primary OA, DDH-OA, and control subjects with no history of hip disease were included. CT images were used to measure PI, sagittal femoral head coverage, α angle, and acetabular anteversion. PI was also subdivided into three categories: high PI (larger than 64.0°), medium PI (42.0° to 64.0°), and low PI (less than 42.0°). The anterior centre edge angles, posterior centre edge angles, and total sagittal femoral head coverage were measured. The correlations between PI and sagittal femoral head coverage, α angle, and acetabular anteversion were examined.Aims
Methods
Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement. We recruited nine participants with cam and/or pincer morphologies and with pain, 13 participants with cam and/or pincer morphologies and without pain, and 11 controls from a population-based cohort. We scanned hips in active squatting and passive sitting flexion, adduction, and internal rotation using open MRI and quantified anterior femoroacetabular clearance using the β angle.Aims
Methods
The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate. This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database.Aims
Methods
This study reports mid-term outcomes after periacetabular osteotomy (PAO) exclusively in a borderline hip dysplasia (BHD) population to provide a contrast to published outcomes for arthroscopic surgery of the hip in BHD. We identified 42 hips in 40 patients treated between January 2009 and January 2016 with BHD defined as a lateral centre-edge angle (LCEA) of ≥ 18° but < 25°. A minimum five-year follow-up was available. Patient-reported outcomes (PROMs) including Tegner score, subjective hip value (SHV), modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. The following morphological parameters were evaluated: LCEA, acetabular index (AI), α angle, Tönnis staging, acetabular retroversion, femoral version, femoroepiphyseal acetabular roof index (FEAR), iliocapsularis to rectus femoris ratio (IC/RF), and labral and ligamentum teres (LT) pathology.Aims
Methods
Hip dysplasia (HD) leads to premature osteoarthritis. Timely detection and correction of HD has been shown to improve pain, functional status, and hip longevity. Several time-consuming radiological measurements are currently used to confirm HD. An artificial intelligence (AI) software named HIPPO automatically locates anatomical landmarks on anteroposterior pelvis radiographs and performs the needed measurements. The primary aim of this study was to assess the reliability of this tool as compared to multi-reader evaluation in clinically proven cases of adult HD. The secondary aims were to assess the time savings achieved and evaluate inter-reader assessment. A consecutive preoperative sample of 130 HD patients (256 hips) was used. This cohort included 82.3% females (n = 107) and 17.7% males (n = 23) with median patient age of 28.6 years (interquartile range (IQR) 22.5 to 37.2). Three trained readers’ measurements were compared to AI outputs of lateral centre-edge angle (LCEA), caput-collum-diaphyseal (CCD) angle, pelvic obliquity, Tönnis angle, Sharp’s angle, and femoral head coverage. Intraclass correlation coefficients (ICC) and Bland-Altman analyses were obtained.Aims
Methods
Acetabular retroversion is a recognized cause of hip impingement and can be influenced by pelvic tilt (PT), which changes in different functional positions. Positional changes in PT have not previously been studied in patients with acetabular retroversion. Supine and standing anteroposterior (AP) pelvic radiographs were retrospectively analyzed in 69 patients treated for symptomatic acetabular retroversion. Measurements were made for acetabular index (AI), lateral centre-edge angle (LCEA), crossover index, ischial spine sign, and posterior wall sign. The change in the angle of PT was measured both by the sacro-femoral-pubic (SFP) angle and the pubic symphysis to sacroiliac (PS-SI) index.Aims
Methods
Periacetabular osteotomy (PAO) is an established treatment for acetabular dysplasia. It has also been proposed as a treatment for patients with acetabular retroversion. By reviewing a large cohort, we aimed to test whether outcome is equivalent for both types of morphology and identify factors that influenced outcome. A single-centre, retrospective cohort study was performed on patients with acetabular retroversion treated with PAO (n = 62 hips). Acetabular retroversion was diagnosed clinically and radiologically (presence of a crossover sign, posterior wall sign, lateral centre-edge angle (LCEA) between 20° and 35°). Outcomes were compared with a control group of patients undergoing PAO for dysplasia (LCEA < 20°; n = 86 hips). Femoral version was recorded. Patient-reported outcome measures (PROMs), complications, and reoperation rates were measured.Aims
Methods
This paper aims to review the evidence for patient-related factors associated with less favourable outcomes following hip arthroscopy. Literature reporting on preoperative patient-related risk factors and outcomes following hip arthroscopy were systematically identified from a computer-assisted literature search of Pubmed (Medline), Embase, and Cochrane Library using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and a scoping review.Aims
Methods
Our retrospective analysis reports the outcome of patients operated for slipped capital femoral epiphysis using the modified Dunn procedure. Results, complications, and the need for revision surgery are compared with the recent literature. We retrospectively evaluated 17 patients (18 hips) who underwent the modified Dunn procedure for the treatment of slipped capital femoral epiphysis. Outcome measurement included standardized scores. Clinical assessment included ambulation, leg length discrepancy, and hip mobility. Radiographically, the quality of epiphyseal reduction was evaluated using the Southwick and Alpha-angles. Avascular necrosis, heterotopic ossifications, and osteoarthritis were documented at follow-up.Aims
Methods
The modified Dunn procedure has the potential to restore the anatomy in hips with severe slipped capital femoral epiphyses (SCFE). However, there is a risk of developing avascular necrosis of the femoral head (AVN). In this paper, we report on clinical outcome, radiological outcome, AVN rate and complications, and the cumulative survivorship at long-term follow-up in patients undergoing the modified Dunn procedure for severe SCFE. We performed a retrospective analysis involving 46 hips in 46 patients treated with a modified Dunn procedure for severe SCFE (slip angle > 60°) between 1999 and 2016. At nine-year-follow-up, 40 hips were available for clinical and radiological examination. Mean preoperative age was 13 years, and 14 hips (30%) presented with unstable slips. Mean preoperative slip angle was 64°. Kaplan–Meier survivorship was calculated.Aims
Patients and Methods
A borderline dysplastic hip can behave as either stable or unstable and this makes surgical decision making challenging. While an unstable hip may be best treated by acetabular reorientation, stable hips can be treated arthroscopically. Several imaging parameters can help to identify the appropriate treatment, including the Femoro-Epiphyseal Acetabular Roof (FEAR) index, measured on plain radiographs. The aim of this study was to assess the reliability and the sensitivity of FEAR index on MRI compared with its radiological measurement. The technique of measuring the FEAR index on MRI was defined and its reliability validated. A retrospective study assessed three groups of 20 patients: an unstable group of ‘borderline dysplastic hips’ with lateral centre edge angle (LCEA) less than 25° treated successfully by periacetabular osteotomy; a stable group of ‘borderline dysplastic hips’ with LCEA less than 25° treated successfully by impingement surgery; and an asymptomatic control group with LCEA between 25° and 35°. The following measurements were performed on both standardized radiographs and on MRI: LCEA, acetabular index, femoral anteversion, and FEAR index.Aims
Patients and Methods
The number of patients undergoing arthroscopic surgery of the
hip has increased significantly during the past decade. It has now
become an established technique for the treatment of many intra-
and extra-articular conditions affecting the hip. However, it has
a steep learning curve and is not without the risk of complications.
The purpose of this systematic review was to determine the prevalence
of complications during and following this procedure. Preferred Reporting Items for Systematic Reviews and Meta-Analyses
guidelines were used in designing this study. Two reviewers systematically
searched the literature for complications related to arthroscopy
of the hip. The research question and eligibility criteria were
established Aims
Materials and Methods
The purpose of this study was to compare the thickness of the hip capsule in patients with surgical hip disease, either with cam-femoroacetabular impingement (FAI) or non-FAI hip pathology, with that of asymptomatic control hips. A total of 56 hips in 55 patients underwent a 3Tesla MRI of the hip. These included 40 patients with 41 hips with arthroscopically proven hip disease (16 with cam-FAI; nine men, seven women; mean age 39 years, 22 to 58) and 25 with non-FAI chondrolabral pathology (four men, 21 women; mean age 40 years, 18 to 63) as well as 15 asymptomatic volunteers, whose hips served as controls (ten men, five women; mean age 62 years, 33 to 77). The maximal capsule thickness was measured anteriorly and superiorly, and compared within and between the three groups with a gender subanalysis using student’s Objectives
Methods
The primary aim of this study was to define and quantify three
new measurements to indicate the position of the greater trochanter.
Secondary aims were to define ‘functional antetorsion’ as it relates
to abductor function in populations both with and without torsional
abnormality. Three new measurements, functional antetorsion, posterior tilt,
and posterior translation of the greater trochanter, were assessed
from 61 CT scans of cadaveric femurs, and their reliability determined.
These measurements and their relationships were also evaluated in
three groups of patients: a control group (n = 22), a ‘high-antetorsion’ group
(n = 22) and a ‘low-antetorsion’ group (n = 10).Aims
Patients and Methods
The spinopelvic relationship (including pelvic incidence) has been shown to influence pelvic orientation, but its potential association with femoroacetabular impingement has not been thoroughly explored. The purpose of this study was to prove the hypothesis that decreasing pelvic incidence is associated with increased risk of cam morphology. Two matching cohorts were created from a collection of cadaveric specimens with known pelvic incidences: 50 subjects with the highest pelvic incidence (all subjects > 60°) and 50 subjects with the lowest pelvic incidence (all subjects < 35°). Femoral version, acetabular version, and alpha angles were directly measured from each specimen bilaterally. Cam morphology was defined as alpha angle > 55°. Differences between the two cohorts were analysed with a Student’s Objectives
Methods
The repair of chondral lesions associated with
femoroacetabular impingement requires specific treatment in addition
to that of the impingement. In this single-centre retrospective
analysis of a consecutive series of patients we compared treatment
with microfracture (MFx) with a technique of enhanced microfracture
autologous matrix-induced chondrogenesis (AMIC). Acetabular grade III and IV chondral lesions measuring between
2 cm2 and 8 cm2 in 147 patients were treated
by MFx in 77 and AMIC in 70. The outcome was assessed using the
modified Harris hip score at six months and one, two, three, four
and five years post-operatively. The outcome in both groups was
significantly improved at six months and one year post-operatively.
During the subsequent four years the outcome in the MFx group slowly deteriorated,
whereas that in the AMIC group remained stable. Six patients in
the MFx group subsequently required total hip arthroplasty, compared
with none in the AMIC group We conclude that the short-term clinical outcome improves in
patients with acetabular chondral damage following both MFx and
AMIC. However, the AMIC group had better and more durable improvement,
particularly in patients with large (≥ 4 cm2) lesions. Cite this article:
The cam-type deformity in femoroacetabular impingement
is a 3D deformity. Single measurements using radiographs, CT or
MRI may not provide a true estimate of the magnitude of the deformity.
We performed an analysis of the size and location of measurements
of the alpha angle (α°) using a CT technique which could be applied
to the 3D reconstructions of the hip. Analysis was undertaken in
42 patients (57 hips; 24 men and 18 women; mean age 38 years (16
to 58)) who had symptoms of femoroacetabular impingement related
to a cam-type abnormality. An α° of >
50° was considered a significant
indicator of cam-type impingement. Measurements of the α° were made
at different points around the femoral head/neck junction at intervals
of 30°: starting at the nine o’clock (posterior), ten, eleven and
twelve o’clock (superior), one, two and ending at three o’clock
(anterior) position. The mean maximum increased α° was 64.6° (50.8° to 86°). The two
o’clock position was the most common point to find an increased α°
(53 hips; 93%), followed by one o’clock (48 hips; 84%). The largest α°
for each hip was found most frequently at the two o’clock position
(46%), followed by the one o’clock position (39%). Generally, raised α angles
extend over three segments of the clock face. Single measurements of the α°, whether pre- or post-operative,
should be viewed with caution as they may not be representative
of the true size of the deformity and not define whether adequate
correction has been achieved following surgery. Cite this article:
Joint-preserving surgery of the hip (JPSH) has evolved considerably
and now includes a number of procedures, including arthroscopy,
surgical dislocation, and redirectional osteotomies of the femur
and acetabulum. There are a number of different factors which lead
to failure of JPSH. Consequently, it is of interest to assess the
various modes of failure in order to continue to identify best practice
and the indications for these procedures. Using a retrospective observational study design, we reviewed
1013 patients who had undergone JPSH by a single surgeon between
2005 and 2015. There were 509 men and 504 women with a mean age
of 39 years (16 to 78). Of the 1013 operations, 783 were arthroscopies,
122 surgical dislocations, and 108 peri-acetabular osteotomies (PAO).
We analysed the overall failure rates and modes of failure. Re-operations
were categorised into four groups: Mode 1 was arthritis progression
or organ failure leading to total hip arthroplasty (THA); Mode 2
was an Incorrect diagnosis/procedure; Mode 3 resulted from malcorrection
of femur (type A), acetabulum (type B), or labrum (type C) and Mode 4
resulted from an unintended consequence of the initial surgical
intervention.Aims
Patients and Methods
The use of joint-preserving surgery of the hip
has been largely abandoned since the introduction of total hip replacement.
However, with the modification of such techniques as pelvic osteotomy,
and the introduction of intracapsular procedures such as surgical
hip dislocation and arthroscopy, previously unexpected options for
the surgical treatment of sequelae of childhood conditions, including
developmental dysplasia of the hip, slipped upper femoral epiphysis
and Perthes’ disease, have become available. Moreover, femoroacetabular
impingement has been identified as a significant aetiological factor
in the development of osteoarthritis in many hips previously considered to
suffer from primary osteoarthritis. As mechanical causes of degenerative joint disease are now recognised
earlier in the disease process, these techniques may be used to
decelerate or even prevent progression to osteoarthritis. We review
the recent development of these concepts and the associated surgical
techniques. Cite this article:
Acetabular labral tears and associated intra-articular
pathology of the hip have been recognised as a source of symptoms.
However, it is now appreciated that there is a relatively high prevalence
of asymptomatic labral tears. In this study, 70 young asymptomatic
adult volunteers with a mean age of 26 years (19 to 41) were recruited
and underwent three tesla non-arthrographic MR scans. There were
47 women (67.1%) and 23 men (32.9%). Labral tears were found in 27 volunteers (38.6%); these were
an isolated finding in 16 (22.9%) and were associated with other
intra-articular pathology in the remaining 11 (15.7%) volunteers.
Furthermore, five (7.1%) had intra-articular pathology without an
associated labral tear. Given the high prevalence of labral pathology in the asymptomatic
population, it is important to confirm that a patient's symptoms
are due to the demonstrated abnormalities when considering surgery. Cite this article:
We have reviewed the current literature to compare
the results of surgery aimed to repair or debride a damaged acetabular
labrum. We identified 28 studies to be included in the review containing
a total of 1631 hips in 1609 patients. Of these studies 12 reported
a mean rate of good results of 82% (from 67% to 100%) for labral debridement.
Of the 16 studies that reported a combination of debridement and
re-attachment, five reported a comparative outcome for the two methods,
four reported better results with re-attachment and one study did
not find any significant difference in outcomes. Due to the heterogeneity
of the studies it was not possible to perform a meta-analysis or
draw accurate conclusions. Confounding factors in the studies include
selection bias, use of historical controls and high rates of loss
of follow-up. It seems logical to repair an unstable tear in a good quality
labrum with good potential to heal in order potentially to preserve
its physiological function. A degenerative labrum on the other hand
may be the source of discomfort and its preservation may result
in persistent pain and the added risk of failure of re-attachment.
The results of the present study do not support routine refixation
for all labral tears. Cite this article:
Our understanding of the origin of hip pain in
degenerative disorders of the hip, including primary osteoarthritis, avascular
necrosis and femoroacetabular impingement (FAI), is limited. We
undertook a histological investigation of the nociceptive innervation
of the acetabular labrum, ligamentum teres and capsule of the hip,
in order to prove pain- and proprioceptive-associated marker expression.
These structures were isolated from 57 patients who had undergone
elective hip surgery (44 labral samples, 33 ligamentum teres specimens,
34 capsular samples; in 19 patients all three structures were harvested).
A total of
15 000 histological sections were prepared that were investigated
immunohistochemically for the presence of protein S-100, 68 kDa
neurofilament, neuropeptide Y, nociceptin and substance P. The tissues
were evaluated in six representative areas. Within the labrum, pain-associated free nerve ending expression
was located predominantly at its base, decreasing in the periphery.
In contrast, the distribution within the ligamentum teres showed
a high local concentration in the centre. The hip capsule had an
almost homogeneous marker expression in all investigated areas. This study showed characteristic distribution profiles of nociceptive
and pain-related nerve fibres, which may help in understanding the
origin of hip pain. Cite this article:
The acetabular labrum is a soft-tissue structure
which lines the acetabular rim of the hip joint. Its role in hip
joint biomechanics and joint health has been of particular interest
over the past decade. In normal hip joint biomechanics, the labrum
is crucial in retaining a layer of pressurised intra-articular fluid
for joint lubrication and load support/distribution. Its seal around
the femoral head is further regarded as a contributing to hip stability through
its suction effect. The labrum itself is also important in increasing
contact area thereby reducing contact stress. Given the labrum’s
role in normal hip joint biomechanics, surgical techniques for managing
labral damage are continuously evolving as our understanding of
its anatomy and function continue to progress. The current paper
aims to review the anatomy and biomechanical function of the labrum
and how they are affected by differing surgical techniques. Take home message: The acetabular labrum plays a critical role
in hip function and maintaining and restoring its function during
surgical intervention remain an essential goal. Cite this article:
We report on gender-specific reference intervals
of the alpha angle and its association with other qualitative cam-type
findings in femoroacetabular impingement at the hip, according to
a population-based cohort of 2038 19-year-olds, 1186 of which were
women (58%). The alpha angle was measured on standardised frog-leg
lateral and anteroposterior (AP) views using digital measurement
software, and qualitative cam-type findings were assessed subjectively
on both views by independent observers. In all, 2005 participants
(837 men, 1168 women, mean age 18.6 years (17.2 to 20.1) were included
in the analysis. For the frog-leg view, the mean alpha angle (right
hip) was 47° (26 to 79) in men and 42° (29 to 76) in women, with
97.5 percentiles of 68° and 56°, respectively. For the AP view,
the mean values were 62° (40 to 105) and 52° (36 to 103) for men
and women, respectively, with 97.5 percentiles of 93° and 94°. Associations
between higher alpha angles and all qualitative cam-type findings
were seen for both genders on both views. The reference intervals
presented for the alpha angle in this cross-sectional study are
wide, especially for the AP view, with higher mean values for men
than women on both views. Cite this article:
We retrospectively examined the long-term outcome of 96 asymptomatic hips in 96 patients with a mean age of 49.3 years (16 to 65) who had radiological evidence of femoroacetabular impingement. When surveillance commenced there were 17, 34, and 45 hips with cam, pincer, and mixed impingement, respectively. Overall, 79 hips (82.3%) remained free of osteoarthritis for a mean of 18.5 years (10 to 40). In contrast, 17 hips (17.7%) developed osteoarthritis at a mean of 12 years (2 to 28). No statistically significant difference was found in the rates of development of osteoarthritis among the three groups (p = 0.43). Regression analysis showed that only the presence of idiopathic osteoarthritis of the contralateral diseased hip was predictive of development of osteoarthritis on the asymptomatic side (p = 0.039). We conclude that a substantial proportion of hips with femoroacetabular impingement may not develop osteoarthritis in the long-term. Accordingly, in the absence of symptoms, prophylactic surgical treatment is not warranted.
The aim of this study was to evaluate the long-term clinical
and radiographic outcomes of the Birmingham Interlocking Pelvic
Osteotomy (BIPO). In this prospective study, we report the mid- to long-term clinical
outcomes of the first 100 consecutive patients (116 hips; 88 in
women, 28 in men) undergoing BIPO, reflecting the surgeon’s learning
curve. Failure was defined as conversion to hip arthroplasty. The
mean age at operation was 31 years (7 to 57). Three patients (three
hips) were lost to follow-up.Aims
Patients and Methods
The β-angle is a radiological tool for measuring the distance between the pathological head-neck junction and the acetabular rim with the hip in 90° of flexion in patients with femoroacetabular impingement. Initially it was measured using an open-chamber MRI. We have developed a technique to measure this angle on plain radiographs. Correlation analysis was undertaken to determine the relationship between the range of movement and the β-angle in 50 patients with femoroacetabular impingement and 50 asymptomatic control subjects. Inter- and intra-observer reliability of the β-angle was also evaluated. Patients with femoroacetabular impingement had a significantly smaller (p <
0.001) mean β-angle (15.6°, 95% confidence interval (CI) 13.3 to 17.7) compared with the asymptomatic group (38.7°, 95% CI 36.5 to 41.0). Correlation between internal rotation and the β-angle was high in the impingement group and moderate in the asymptomatic group. The β-angle had excellent inter- and intra-observer reliability in both groups. Our findings suggest that the measurement of the β-angle on plain radiography may represent a valid, reproducible and cost-effective alternative to open MRI in the assessment of the pathological bony anatomy in patients with cam, pincer and mixed femoroacetabular impingement.
Hip arthroscopy is particularly attractive in
children as it confers advantages over arthrotomy or open surgery,
such as shorter recovery time and earlier return to activity. Developments
in surgical technique and arthroscopic instrumentation have enabled
extension of arthroscopy of the hip to this age group. Potential
challenges in paediatric and adolescent hip arthroscopy include
variability in size, normal developmental change from childhood to
adolescence, and conditions specific to children and adolescents
and their various consequences. Treatable disorders include the
sequelae of traumatic and sports-related hip joint injuries, Legg–Calve–Perthes’
disease and slipped capital femoral epiphysis, and the arthritic
and septic hip. Intra-articular abnormalities are rarely isolated and
are often associated with underlying morphological changes. This review presents the current concepts of hip arthroscopy
in the paediatric and adolescent patient, covering clinical assessment
and investigation, indications and results of the experience to
date, as well as technical challenges and future directions.
Femoroacetabular impingement causes pain in the hip in young adults and may predispose to the development of osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis of the hip and may have a role in that of femoroacetabular impingement. We compared 96 siblings of 64 patients treated for primary impingement with a spouse control group of 77 individuals. All the subjects were screened clinically and radiologically using a standardised protocol for the presence of cam and pincer deformities and osteoarthritis. The siblings of those patients with a cam deformity had a relative risk of 2.8 of having the same deformity (66 of 160 siblings hips versus 23 of 154 control hips, p <
0.00001). The siblings of those patients with a pincer deformity had a relative risk of 2.0 of having the same deformity (43 of 116 sibling hips versus 29 of 154 control hips, p = 0.001). Bilateral deformity occurred more often in the siblings (42 of 96 siblings versus 13 of 77 control subjects, relative risk 2.6, p = 0.0002). The prevalence of clinical features in those hips with abnormal morphology was also greater in the sibling group compared with the control group (41 of 109 sibling hips versus 7 of 46 control hips, relative risk 2.5, p = 0.007). In 11 sibling hips there was grade-2 osteoarthritis according to Kellgren and Lawrence versus none in the control group (p = 0.002). Genetic influences are important in the aetiology of primary femoroacetabular impingement. This risk appears to be manifested through not only abnormal joint morphology, but also through other factors which may modulate progression of the disease.
To confirm whether developmental dysplasia of
the hip has a risk of hip impingement, we analysed maximum ranges
of movement to the point of bony impingement, and impingement location
using three-dimensional (3D) surface models of the pelvis and femur
in combination with 3D morphology of the hip joint using computer-assisted methods.
Results of computed tomography were examined for 52 hip joints with
DDH and 73 normal healthy hip joints. DDH shows larger maximum extension
(p = 0.001) and internal rotation at 90° flexion (p <
0.001).
Similar maximum flexion (p = 0.835) and external rotation (p = 0.713)
were observed between groups, while high rates of extra-articular
impingement were noticed in these directions in DDH (p <
0.001).
Smaller cranial acetabular anteversion (p = 0.048), centre-edge
angles (p <
0.001), a circumferentially shallower acetabulum,
larger femoral neck anteversion (p <
0.001), and larger alpha
angle were identified in DDH. Risk of anterior impingement in retroverted
DDH hips is similar to that in retroverted normal hips in excessive
adduction but minimal in less adduction. These findings might be
borne in mind when considering the possibility of extra-articular
posterior impingement in DDH being a source of pain, particularly
for patients with a highly anteverted femoral neck. Cite this article:
We reviewed the clinical outcome of arthroscopic femoral osteochondroplasty for cam femoroacetabular impingement performed between August 2005 and March 2009 in a series of 40 patients over 60 years of age. The group comprised 26 men and 14 women with a mean age of 65 years (60 to 82). The mean follow-up was 30 months (12 to 54). The mean modified Harris hip score improved by 19.2 points (95% confidence interval 13.6 to 24.9; p <
0.001) while the mean non-arthritic hip score improved by 15.0 points (95% confidence interval 10.9 to 19.1, p <
0.001). Seven patients underwent total hip replacement after a mean interval of 12 months (6 to 24 months) at a mean age of 63 years (60 to 70). The overall level of satisfaction was high with most patients indicating that they would undergo similar surgery in the future to the contralateral hip, if indicated. No serious complications occurred. Arthroscopic femoral osteochondroplasty performed in selected patients over 60 years of age, who have hip pain and mechanical symptoms resulting from cam femoroacetabular impingement, is beneficial with a minimal risk of complications at a mean follow-up of 30 months.
To determine the effect of a change in design of a cementless
ceramic acetabular component in fixation and clinical outcome after
total hip arthroplasty We compared 342 hips (302 patients) operated between 1999 and
2005 with a relatively smooth hydroxyapatite coated acetabular component
(group 1), and 337 hips (310 patients) operated between 2006 and
2011 using a similar acetabular component with a macrotexture on
the entire outer surface of the component (group 2). The mean age of
the patients was 53.5 (14 to 70) in group 1 and 53.0 (15 to 70)
in group 2. The mean follow-up was 12.7 years (10 to 17) for group
1 and 7.2 years (4 to 10) for group 2.Aims
Patients and Methods
Labral tears are commonly associated with femoroacetabular impingement. We reviewed 151 patients (156 hips) with femoroacetabular impingement and labral tears who had been treated arthroscopically. These were subdivided into those who had undergone a labral repair (group 1) and those who had undergone resection of the labrum (group 2). In order to ensure the groups were suitably matched for comparison of treatment effects, patients with advanced degenerative changes (Tönnis grade >
2, lateral sourcil height <
2 mm and Outerbridge grade 4 changes in the weight-bearing area of the femoral head) were excluded, leaving 96 patients (101 hips) in the study. At a mean follow-up of 2.44 years (2 to 4), the mean modified Harris hip score in the labral repair group (group 1, 69 hips) improved from 60.2 (24 to 85) pre-operatively to 93.6 (55 to 100), and in the labral resection group (group 2, 32 hips) from 62.8 (29 to 96) pre-operatively to 88.8 (35 to 100). The mean modified Harris hip score in the labral repair group was 7.3 points greater than in the resection group (p = 0.036, 95% confidence interval 0.51 to 14.09). Labral detachments were found more frequently in the labral repair group and labral flap tears in the resection group. No patient in our study group required a subsequent hip replacement during the period of follow-up. This study shows that patients without advanced degenerative changes in the hip can achieve significant improvement in their symptoms after arthroscopic treatment of femoroacetabular impingement. Where appropriate, labral repair provides a superior result to labral resection.
The aim of this study was to determine the accuracy
of registration and the precision of the resection volume in navigated
hip arthroscopy for cam-type femoroacetabular impingement, using
imageless and image-based registration. A virtual cam lesion was
defined in 12 paired cadaver hips and randomly assigned to either
imageless or image-based (three-dimensional (3D) fluoroscopy) navigated
arthroscopic head–neck osteochondroplasty. The accuracy of patient–image
registration for both protocols was evaluated and post-operative
imaging was performed to evaluate the accuracy of the surgical resection.
We found that the estimated accuracy of imageless registration in the
arthroscopic setting was poor, with a mean error of 5.6 mm (standard
deviation ( In conclusion, given the limited femoral surface that can be
reached and digitised during arthroscopy of the hip, imageless registration
is inaccurate and does not allow for reliable surgical navigation.
However, image-based registration does acceptably allow for guided
femoral osteochondroplasty in the arthroscopic management of femoroacetabular
impingement.
There is a known association between femoroacetabular impingement and osteoarthritis of the hip. What is not known is whether arthroscopic excision of an impingement lesion can significantly improve a patient’s symptoms. This study compares the results of hip arthroscopy for cam-type femoracetabular impingement in two groups of patients at one year. The study group comprised 24 patients (24 hips) with cam-type femoroacetabular impingement who underwent arthroscopic debridement with excision of their impingement lesion (osteoplasty). The control group comprised 47 patients (47 hips) who had arthroscopic debridement without excision of the impingement lesion. In both groups, the presence of femoroacetabular impingement was confirmed on pre-operative plain radiographs. The modified Harris hip score was used for evaluation pre-operatively and at one-year. Non-parametric tests were used for statistical analysis. A tendency towards a higher median post-operative modified Harris hip score was observed in the study group compared with the control group (83 vs 77, p = 0.11). There was a significantly higher proportion of patients in the osteoplasty group with excellent/good results compared with the controls (83% vs 60%, p = 0.043). Additional symptomatic improvement may be obtained after hip arthroscopy for femoroacetabular impingement by the inclusion of femoral osteoplasty.
The radiological evaluation of the anterolateral femoral head is an essential tool for the assessment of the cam type of femoroacetabular impingement. CT, MRI and frog lateral plain radiographs have all been suggested as imaging options for this type of lesion. The alpha angle is accepted as a reliable indicator of the cam type of impingement and may also be used as an assessment for the successful operative correction of the cam lesion. We studied the alpha angles of 32 consecutive patients with femoroacetabular impingement. The angle measured on frog lateral radiographs using templating tools was compared with that measured on CT scans in order to assess the reliability of the frog lateral view in analysing the alpha angle in cam impingement. A high interobserver reliability was noted for the assessment of the alpha angle on the frog lateral view with an intraclass correlation coefficient of 0.83. The mean alpha angle measured on the frog lateral view was 58.71° (32° to 83.3°) and that by CT was 65.11° (30° to 102°). A poor intraclass correlation coefficient (0.08) was noted between the measurements using the two systems. The frog lateral plain radiograph is not reliable for measuring the alpha angle. Various factors may be responsible for this such as the projection of the radiograph, the positioning of the patient and the quality of the image. CT may be necessary for accurate measurement of the alpha angle.
Over an eight-month period we prospectively enrolled 122 patients who underwent arthroscopic surgery of the hip for femoroacetabular impingement and met the inclusion criteria for this study. Patients with bilateral hip arthroscopy, avascular necrosis and previous hip surgery were excluded. Ten patients refused to participate leaving 112 in the study. There were 62 women and 50 men. The mean age of the patients was 40.6 yrs (95% confidence interval (CI) 37.7 to 43.5). At arthroscopy, 23 patients underwent osteoplasty only for cam impingement, three underwent rim trimming only for pincer impingement, and 86 underwent both procedures for mixed-type impingement. The mean follow-up was 2.3 years (2.0 to 2.9). The mean modified Harris hip score (HHS) improved from 58 to 84 (mean difference = 24 (95% CI 19 to 28)) and the median patient satisfaction was 9 (1 to 10). Ten patients underwent total hip replacement at a mean of 16 months (8 to 26) after arthroscopy. The predictors of a better outcome were the pre-operative modified HHS (p = 0.018), joint space narrowing ≥ 2 mm (p = 0.005), and repair of labral pathology instead of debridement (p = 0.032). Hip arthroscopy for femoroacetabular impingement, accompanied by suitable rehabilitation, gives a good short-term outcome and high patient satisfaction.
In this Cite this article:
Femoroacetabular impingement is a cause of hip pain in adults and is potentially a precursor of osteoarthritis. Our aim in this study was to determine the prevalence of bilateral deformity in patients with symptomatic cam-type femoroacetabular impingement as well as the presence of associated acetabular abnormalities and hip pain. We included all patients aged 55 years or less seen by the senior author for hip pain, with at least one anteroposterior and lateral pelvic radiograph available. All patients with dysplasia and/or arthritis were excluded. A total of 113 patients with a symptomatic cam-impingement deformity of at least one hip was evaluated. There were 82 men and 31 women with a mean age of 37.9 years (16 to 55). Bilateral cam-type deformity was present in 88 patients (77.8%) while only 23 of those (26.1%) had bilateral hip pain. Painful hips had a statistically significant higher mean alpha angle than asymptomatic hips (69.9° vs 63.1°, p <
0.001). Hips with an alpha angle of more than 60° had an odds ratio of being painful of 2.59 (95% confidence interval 1.32 to 5.08, p = 0.006) compared with those with an alpha angle of less than 60°. Of the 201 hips with a cam-impingement deformity 42% (84) also had a pincer deformity. Most patients with cam-type femoroacetabular impingement had bilateral deformities and there was an associated acetabular deformity in 84 of 201 patients (42%). This information is important in order to define the natural history of these deformities, and to determine treatment.
Deformity after slipped upper femoral epiphysis
(SUFE) can cause cam-type femoroacetabular impingement (FAI) and
subsequent osteoarthritis (OA). However, there is little information
regarding the radiological assessment and clinical consequences
at long-term follow-up. We reviewed 36 patients (43 hips) previously
treated by We conclude that persistent deformity with radiological cam FAI
after SUFE is associated with poorer clinical and radiological long-term
outcome. Although the radiological measurements had quite wide limits
of agreement, they are useful for the diagnosis of post-slip deformities
in clinical practice.
This study evaluates the outcome of arthroscopic femoral osteochondroplasty for cam lesions of the hip in the absence of additional pathology other than acetabular chondral lesions. We retrospectively reviewed 166 patients (170 hips) who were categorised according to three different grades of chondral damage. The outcome was assessed in each grade using the modified Harris Hip Score (MHHS) and the Non-Arthritic Hip Score (NAHS). Overall, at the last follow-up (mean 22 months, 12 to 72), the mean MHHS had improved by 15.3 points (95% confidence interval (CI), 8.9 to 21.7) and the mean NAHS by 15 points (95% CI, 9.4 to 20.5). Significantly better results were observed in hips with less severe chondral damage. Microfracture in limited chondral lesions showed superior results. Arthroscopic femoral osteochondroplasty for cam impingement with microfracture in selected cases is beneficial. The outcome correlates with the severity of acetabular chondral damage.
Although good to excellent short-term results
of arthroscopic partial limbectomy of the hip have been reported, there
is little information on the long-term outcome of the procedure.
We report a case with a 16-year follow-up. A 34-year old woman presented with a three-month history of severe
pain and limitation of movement of the hip. Plain radiographs and
arthrography showed no abnormality. MRI showed an effusion and a
deformity of the anterosuperior part of the labrum. This was confirmed
as an inverted labral tear that was debrided arthroscopically. At 16 years post-operatively, she remained symptom-free. Plain
radiographs showed no abnormality and MRI suggested that the sealing
effect of the scar tissue prevented articular damage and degeneration.
The purpose of this study was to investigate whether the femoral
head–neck contour, characterised by the alpha angle, varies with
the stage of physeal maturation using MRI evaluation of an asymptomatic
paediatric population. Paediatric volunteers with asymptomatic hips were recruited to
undergo MRI of both hips. Femoral head physes were graded from 1
(completely open) to 6 (completely fused). The femoral head–neck
contour was evaluated using the alpha angle, measured at the 3:00
(anterior) and 1:30 (anterosuperior) positions and correlated with
physeal grade, with gender sub-analysis performed.Objectives
Methods
It is probable that both genetic and environmental
factors play some part in the aetiology of most cases of degenerative
hip disease. Geneticists have identified some single gene disorders
of the hip, but have had difficulty in identifying the genetics
of many of the common causes of degenerative hip disease. The heterogeneity
of the phenotypes studied is part of the problem. A detailed classification
of phenotypes is proposed. This study is based on careful documentation
of 2003 consecutive total hip replacements performed by a single
surgeon between 1972 and 2000. The concept that developmental problems
may initiate degenerative hip disease is supported. The influences
of gender, age and body mass index are outlined. Biomechanical explanations
for some of the radiological appearances encountered are suggested.
The body weight lever, which is larger than the abductor lever, causes
the abductor power to be more important than body weight. The possibility
that a deficiency in joint lubrication is a cause of degenerative
hip disease is discussed. Identifying the phenotypes may help geneticists
to identify genes responsible for degenerative hip disease, and
eventually lead to a definitive classification.
Arthroscopy of the native hip is an established diagnostic and therapeutic procedure. Its application in the symptomatic replaced hip is still being explored. We describe the use of arthroscopy of the hip in 24 symptomatic patients following total hip replacement, resurfacing arthroplasty of the hip and partial resurfacing (study group), and compared it with arthroscopy of the native hip in 24 patients (control group). A diagnosis was made or confirmed at arthroscopy in 23 of the study group and a therapeutic arthroscopic intervention resulted in relief of symptoms in ten of these. In a further seven patients it led to revision hip replacement. In contrast, arthroscopy in the control group was diagnostic in all 24 patients and the resulting arthroscopic therapeutic intervention provided symptomatic relief in 21. The mean operative time in the study group (59.7 minutes (35 to 93)) was less than in the control group (71 minutes (40 to 100), p = 0.04) but the arthroscopic approach was more difficult in the arthroplasty group. We suggest that arthroscopy has a role in the management of patients with a symptomatic arthroplasty when other investigations have failed to provide a diagnosis.