Acetabular Retroversion Research Articles

Morphological Changes of the Hip Commonly Associated With Femoroacetabular Impingement Are Not Correlated With Rotational Range of Hip Motion in Elite Soccer Athletes.

Morphological changes characteristic of femoroacetabular impingement (FAI) are common in soccer players. However, the clinical relevance of such anatomical variations is still not well-defined. We hypothesized that high alpha angle values and/or acetabular retroversion index (ARI) are correlated with rotational range of motion (ROM) of the hip and that there are clinical-radiological diferences between the dominant lower limb (DLL) and nondominant lower limb (NDLL) in professional soccer players. Cross-sectional. Level 3. A total of 59 male professional soccer players (average age 25.5 years, range 18-38 years) were evaluated in the preseason. As main outcome measures, we evaluated the alpha angle and the ARI and hip IR and ER ROM with radiographic analysis. The measurements taken on DLL and NDLL were compared and a significant difference was found between the sides in the ER (P = 0.027), where the DLL measures were 1.54° (95% CI, 0.18-2.89) greater than the NDLL. There were no significant differences between the sides in the measures of IR (P > 0.99), total ROM (P = 0.07), alpha angle (P = 0.250), and ARI (P = 0.079). The correlations between the rotation measurements and the alpha angle in each limb were evaluated and the coefficient values showed no correlation; so also between the ARI and rotation measures. Morphological changes of the femur or acetabulum are not correlated with hip IR and ER ROM in male professional soccer players. ER on the dominant side was greater than on the nondominant side. There was no significant difference in the other measurements between sides. In clinical practice, it is common to attribute loss of hip rotational movement to the presence of FAI. This study shows that anatomical FAI may not have a very strong influence on available hip rotational movement in professional soccer athletes.

Residual lumbar hyperlordosis is associated with worsened hip status 5 years after scoliosis correction in non-ambulant patients with cerebral palsy.

Cerebral palsy (CP) is a static encephalopathy with progressive musculoskeletal pathology. Non-ambulant children (GMFCS IV and V) with CP have high rates of spastic hip disease and neuromuscular scoliosis. The effect of spinal fusion and spinal deformity on hip dislocation following total hip arthroplasty has been well studied, however in CP this remains largely unknown. This study aimed to identify factors associated with worsening postoperative hip status (WHS) following corrective spinal fusion in children with GMFCS IV and V CP. Retrospective review of GMFSC IV and V CP patients in a prospective multicenter database undergoing spinal fusion, with 5years follow-up. WHS was determined by permutations of baseline (BL), 1year, 2years, and 5years hip status and defined by a change from an enlocated hip at BL that became subluxated, dislocated or resected post-op, or a subluxated hip that became dislocated or resected. Hip status was analyzed against patient demographics, hip position, surgical variables, and coronal and sagittal spinal alignment parameters. Cutoff values for parameters at which the relationship with hip status was significant was determined using receiver operating characteristic curves. Logistic regression determined odds ratios for predictors of WHS. Eighty four patients were included. 37 (44%) had WHS postoperatively. ROC analysis and logistic regression demonstrated that the only spinopelvic alignment parameter that significantly correlated with WHS was lumbar hyperlordosis (T12-L5) > 60° (p = 0.028), OR = 2.77 (CI 1.10-6.94). All patients showed an increase in pre-to-postop LL. Change in LL pre-to-postop was no different between groups (p = 0.318), however the WHS group was more lordotic at BL and postop (pre44°/post58° vs pre32°/post51° in the no change group). Age, sex, Risser, hip position, levels fused, coronal parameters, global sagittal alignment (SVA), thoracic kyphosis, and reoperation were not associated with WHS. Postoperative hyperlordosis(> 60°) is a risk factor for WHS at 5years after spinal fusion in non-ambulant CP patients. WHS likely relates to anterior pelvic tilt and functional acetabular retroversion due to hyperlordosis, as well as loss of protective lumbopelvic motion causing anterior femoracetabular impingement. III.

Lomber Disk Hastalığında Kalça Torsiyonel Deformiteleri

Objective: Coexistence of lumbar spine disorder with hip diseases is defined as Hip-Spine syndrome, there might be a relation between torsional deformities of the hip and lumbar disc disease. Purpose of the present study was to find whether hip torsional parameters (femur, acetabular anteversion) and clinical findings (hip range of motion, hip score) differ in patients with lumbar disc disease. Method: Patients with lomber disc herniation (n: 20) and control subjects (n: 20) without any lumbar spine or hip disease were enrolled in the study. Femoral anteversion (FeAv), acetabular anteversion (AA), center of edge angle (CE), degree of hip flexion, extension, Harris Hip scores (HHS) were evaluated bilaterally. Results: HHS score, degree of extension plus flexion was lower at diseased side when it is compared to the control subjects (p < 0.001). Unilaterally affected patients had lower AA than control subjects (AA: 13 ± 40 vs16 ± 20 p: 0.01). Conclusion: As there is a link between hip and spine disorders, present study aims to find whether there is a causal relation between hip torsional deviations and lumbar disc disease. Partially supporting the hypothesis, diseased side had lower degrees of acetabular anteversion compared to control subjects at unilaterally affected patients. Mechanical and /or hip torsional parameters especially the acetabular retroversion may have an etiopathogenetic role in unilateral lumbar disc disease.

Borderline Dysplasia with Acetabular Retroversion: Key Findings in Large Hip Arthroscopy Study Group

Borderline Dysplasia with Acetabular Retroversion: Key Findings in Large Hip Arthroscopy Study Group

MRI-based 3D models of the hip joint enables radiation-free computer-assisted planning of periacetabular osteotomy for treatment of hip dysplasia using deep learning for automatic segmentation

IntroductionBoth Hip Dysplasia(DDH) and Femoro-acetabular-Impingement(FAI) are complex three-dimensional hip pathologies causing hip pain and osteoarthritis in young patients. 3D-MRI-based models were used for radiation-free computer-assisted surgical planning. Automatic segmentation of MRI-based 3D-models are preferred because manual segmentation is time-consuming.To investigate(1) the difference and(2) the correlation for femoral head coverage(FHC) between automatic MR-based and manual CT-based 3D-models and (3) feasibility of preoperative planning in symptomatic patients with hip diseases. MethodsWe performed an IRB-approved comparative, retrospective study of 31 hips(26 symptomatic patients with hip dysplasia or FAI). 3D MRI sequences and CT scans of the hip were acquired. Preoperative MRI included axial-oblique T1 VIBE sequence(0.8 mm3 isovoxel) of the hip joint. Manual segmentation of MRI and CT scans were performed. Automatic segmentation of MRI-based 3D-models was performed using deep learning. Results(1)The difference between automatic and manual segmentation of MRI-based 3D hip joint models was below 1 mm(proximal femur 0.2 ± 0.1 mm and acetabulum 0.3 ± 0.5 mm). Dice coefficients of the proximal femur and the acetabulum were 98 % and 97 %, respectively. (2)The correlation for total FHC was excellent and significant(r = 0.975, p < 0.001) between automatic MRI-based and manual CT-based 3D-models. Correlation for total FHC (r = 0.979, p < 0.001) between automatic and manual MR-based 3D models was excellent.(3)Preoperative planning and simulation of periacetabular osteotomy was feasible in all patients(100 %) with hip dysplasia or acetabular retroversion. ConclusionsAutomatic segmentation of MRI-based 3D-models using deep learning is as accurate as CT-based 3D-models for patients with hip diseases of childbearing age. This allows radiation-free and patient-specific preoperative simulation and surgical planning of periacetabular osteotomy for patients with DDH.

Acetabular retroversion after triple pelvic osteotomy for Legg-Calvé-Perthes disease and its impact on the femoroacetabular impingement: a case/control study at 15 years of follow-up.

The objective of this study was to compare the effect of triple pelvic osteotomy (TPO) in Legg-Calvé-Perthes disease (LCPD) on acetabular version in a group of patients who developed a femoroacetabular impingement (FAI) and a control group without FAI. Patients who received a TPO for unilateral LCPD were retrospectively included. Patients with bilateral LCPDs, requiring TPO with femoral procedures, or with incomplete imaging were excluded. Seven patients with FAI (FAI+) and eight patients without FAI (FAI-) were evaluated at a mean follow-up of 14.8 years. The two groups were comparable in demographic data, age at diagnosis, Herring score, and BMI. We measured anatomical acetabular version on computed tomography scans, the difference (delta) of acetabular version between the operated hip and the healthy hip, the McKibbin (femoral version + acetabular version), Stulberg, and Tönnis scoring system. The two groups were not statistically different on the Stulberg and Tönnis scores. All operated hip acetabula were retroverted, FAI+: -8.41° (range, -44 to 10.5), FAI-: -3.38° (range, -37.3 to 11.5) (P = 0.61). The average delta was FAI+: 23.79° (range, 1.5-59.5), FAI-: 20.14° (range, 5-45.3) (P = 0.68). All seven patients of the FAI+ group have pathologic McKibbin index (<30°) versus only four of the FAI- group (P = 0.03). TPO induces acetabular retroversion in patients with LCPD. This retroversion, assessed in a static benchmark (anterior pelvic plane), does not in itself explain the FAI.

Does the Rule of Thirds Adequately Detect Deficient and Excessive Acetabular Coverage?

Assessment of AP acetabular coverage is crucial for choosing the right surgery indication and for obtaining a good outcome after hip-preserving surgery. The quantification of anterior and posterior coverage is challenging and requires either other conventional projections, CT, MRI, or special measurement software, which is cumbersome, not widely available and implies additional radiation. We introduce the "rule of thirds" as a promising alternative to provide a more applicable and easy method to detect an excessive or deficient AP coverage. This method attributes the intersection point of the anterior (posterior) wall to thirds of the femoral head radius (diameter), the medial third suggesting deficient and the lateral third excessive coverage. What is the validity (area under the curve [AUC], sensitivity, specificity, positive/negative likelihood ratios [LR(+)/LR(-)], positive/negative predictive values [PPV, NPV]) for the rule of thirds to detect (1) excessive and (2) deficient anterior and posterior coverages compared with previously established radiographic values of under-/overcoverage using Hip2Norm as the gold standard? We retrospectively evaluated all consecutive patients between 2003 and 2015 from our institutional database who were referred to our hospital for hip pain and were potentially eligible for joint-preserving hip surgery. We divided the study group into six specific subgroups based on the respective acetabular pathomorphology to cover the entire range of anterior and posterior femoral coverage (dysplasia, overcoverage, severe overcoverage, excessive acetabular anteversion, acetabular retroversion, total acetabular retroversion). From this patient cohort, 161 hips were randomly selected for analysis. Anterior and posterior coverage was determined with Hip2Norm, a validated computer software program for evaluating acetabular morphology. The anterior and posterior wall indices were measured on standardized AP pelvis radiographs, and the rule of thirds was applied by one observer. The detection of excessive anterior and posterior acetabular wall using the rule of thirds revealed an AUC of 0.945 and 0.933, respectively. Also the detection of a deficient anterior and posterior acetabular wall by applying the rule of thirds revealed an AUC of 0.962 and 0.876, respectively. For both excessive and deficient anterior and posterior acetabular coverage, we found high specificities and PPVs but low sensitivities and NPVs. We found a high probability for an excessive (deficient) acetabular wall when this intersection point lies in the lateral (medial) third, which would qualify for surgical correction. On the other hand, if this point is not in the lateral (medial) third, an excessive (deficient) acetabular wall cannot be categorically excluded. Thus, the rule of thirds is very specific but not as sensitive as we had expected. Level II, diagnostic study.

Tonnis Angle and Acetabular Retroversion Measurements in Asymptomatic Hips Are Predictive of Future Hip Pain: A Retrospective, Prognostic Clinical Study.

Background:This study evaluated the prevalence of radiographic abnormalities potentially indicative of femoroacetabular impingement on AP pelvic radiographs in asymptomatic adolescents and young adults and aimed to determine whether the abnormalities were predictive of future hip pain.Methods:AP pelvis images from scoliosis radiographs were obtained from patients 12 to 25 years of age free of any clinical hip/lower extremity symptoms between January 2006 and September 2009. The following radiographic abnormalities were collected: lateral center-edge angle of Wiberg >40° or <25°, Tönnis angle <0° or >10°, acetabular retroversion (crossover sign with a posterior wall sign), acetabular overcoverage (crossover sign without a posterior wall sign), and anterior offset alpha angle, calculated using alpha angle of Nötzli >50°. Patients were retrospectively followed (average 3.11 years) to identify those who subsequently developed hip pain.Results:Of the 233 patients (466 hips) who were asymptomatic at the time of radiographic evaluation, at least one radiographic abnormality was present in 60% (281/466) of the hips. Within that group of hips (n = 281), 69% (195/281) of hips demonstrated a single abnormality, whereas 31% (86/281) of hips were associated with multiple abnormalities. Among all hips (n = 466), a lateral center-edge angle <25° or >40° was the most common radiographic abnormality, present in 27% (127/466) of hips. Anterior offset alpha angle and acetabular overcoverage were the most common abnormalities to present together, found in 5% (25/466) of hips. In the multivariable model, a decreasing Tönnis angle (hazard ratio per 1-degree decrease: 1.25, 95% confidence interval, 1.10–1.42, P = 0.0006) and the presence of acetabular retroversion (hazard ratio: 3.55, 95% confidence interval, 1.15–10.95, P = 0.0272) were predictive of the development of future hip pain.Conclusions:Our study demonstrates a high prevalence of radiographic abnormalities indicative of femoroacetabular impingement in asymptomatic adolescents and young adults. A decrease in Tönnis angle and the presence of acetabular retroversion were predictive of future hip pain.

Acetabular- and femoral orientation after periacetabular osteotomy as a predictor for outcome and osteoarthritis

BackgroundPeriacetabular osteotomy is a successful treatment for hip dysplasia. The results are influenced, however, by optimal positioning of the acetabular fragment, femoral head morphology and maybe even femoral version as well as combined anteversion have an impact. In order to obtain better insight on fragment placement, postoperative acetabular orientation and femoral morphology were evaluated in a midterm follow-up in regard to functional outcome and osteoarthritis progression.MethodsA follow-up examination with 49 prospectively documented patients (66 hips) after periacetabular osteotomy (PAO) was performed after 62.2 ± 18.6 months. Mean age of patients undergoing surgery was 26.7 ± 9.6 years, 40 (82%) of these patients were female. All patients were evaluated with an a.p. pelvic x-ray and an isotropic MRI in order to assess acetabular version, femoral head cover, alpha angle, femoral torsion and combined anteversion. The acetabular version was measured at the femoral head center as well as 0.5 cm below and 0.5 and 1 cm above the femoral head center and in addition seven modified acetabular sector angles were determined. Femoral torsion was assessed in an oblique view of the femoral neck. The combined acetabular and femoral version was calculated as well. To evaluate the clinical outcome the pre- and postoperative WOMAC score as well as postoperative Oxford Hip Score and Global Treatment Outcome were analyzed.ResultsAfter PAO acetabular version at the femoral head center (31.4 ± 9.6°) was increased, the anterior cover at the 15 o’clock position (34.7 ± 15.4°) was reduced and both correlated significantly with progression of osteoarthritis, although not with the functional outcome. Combined acetabular and femoral torsion had no influence on the progression of osteoarthritis or outcome scores.ConclusionLong-term results after PAO are dependent on good positioning of the acetabular fragment in all 3 planes. Next to a good lateral coverage a balanced horizontal alignment without iatrogenic pincer impingement due to acetabular retroversion, or insufficient coverage of the anterior femoral head is important.

The Salter innominate osteotomy does not lead to acetabular retroversion

In children with developmental dysplasia of the hip (DDH), Salter's innominate osteotomy aims to surgically manipulate the acetabulum to increase anterior coverage and aid joint support. Consequently, this procedure may retrovert the acetabulum, predisposing patients to pain, osteoarthritis, impingement, or further surgical intervention. In this study, we aim to address whether the innominate osteotomy leads to acetabular retroversion postoperatively or at follow-up. Ninety-two patients were identified from our institutions DDH database between 2009 and 2016, who underwent a unilateral innominate osteotomy for DDH, performed by expert surgeons in a leading paediatric hospital. A novel technique was utilized to measure acetabular version on postoperative computed tomography (CT) scans, where acetabular version was compared between the pathological and contralateral control hips. Measurement of acetabular version in postoperative and control hips demonstrated no incidence of acetabular retroversion. A significant difference was observed when comparing the acetabular version of control versus post-operative hips (P < 0.001), where hips postinnominate osteotomy had a larger degree of acetabular anteversion compared to the control hip. Furthermore, on follow-up radiographic imaging, there was no evidence of acetabular retroversion when using previously defined markers. This study confirms that the Salter innominate osteotomy does not lead to acetabular retroversion both immediately post-operatively and throughout follow-up. In fact, it demonstrates that the acetabula are more anteverted than the contralateral control hip, which has not been previously documented. Additionally, this study demonstrates a novel method of measuring acetabular retroversion using CT technology that adjusts for pelvic tilt, which is repeatable among individuals.

Three-dimensional acetabular orientation during periacetabular osteotomy: a video analysis of acetabular rim position using an external fixator as navigation tool during reorientation procedure

IntroductionBernese periacetabular osteotomy is an effective procedure for treating acetabular dysplasia. However, limited visual control of the acetabular position during surgery may result in under- or overcorrection with residual dysplasia or femoroacetabular impingement. Thus, we wanted to find a simple method to control the effect of correction in the sagittal and coronal plane.MethodThe acetabular coordinates are shown by two perpendicular tubes of an external fixator mounted onto a third tube that is fixed to the acetabular fragment with two Schanz screws. This method enables the isolated acetabular reorientation in the coronal, sagittal, and transverse plane. In a sawbone pelvis model, the acetabular rim is marked with a copper wire and a silicon adherent. To show the radiographic effect on acetabular parameters and the rim position, we visualized correction in the coronal and sagittal plane under fluoroscopic control.ResultsLateral rotation of the acetabular fragment had the highest impact on radiographic lateral coverage of the femoral head. But also ventral coverage increased during isolated lateral rotation. Anterior rotation showed almost no effect on lateral coverage and just a little effect on ventral coverage but caused severe total acetabular retroversion.ConclusionThree-dimensional control of the acetabular orientation during periacetabular osteotomy is important to avoid over- and under-correction. Isolated lateral rotation of the acetabular fragment should be the predominant direction of correction during periacetabular osteotomy. Ambitious anterior correction may be the main source for severe acetabular retroversion following periacetabular osteotomy.

To evaluate the treatment modality by CE angle of Wiberg in various hip joint pathologies

Objective: To evaluate the treatment modality by CE angle of Wiberg in various Hip joint pathologies. Method: This is a non-Randomised Prospective, observational study carried out at Department of Orthopaedics, Index medical college hospital and research centre, Indore (M.P.) during the period of 15 months from January 2018 to March 2019. Ethical clearance taken by Ethical Committee. In this study 35 hips of 28 patients who fulfilled our inclusion criteria were included. In our study patients with hip pathologies with age more than 5 years of both genders, hip pathologies like CAM and/or Pincer type of Femoroacetabular impingement, Acetabular retroversion, Perthes like deformity, Osteoarthritis Hip, Avascular necrosis of femoral head, Developmental dysplasia of hip, Patients who are doubtful for hip preservation or salvage procedure, who were willing to provide their voluntary written informed consent were included. Patients with congenital hip pathologies were exclude. In this study, we assessed the CE angle of Wiberg, in various aspheric hip conditions and formulate a protocol for further management of these Hip pathologies. Result: In this prospective study total 28 patients (35 Hips) of various hip pathologies 21 males (25 hips) 75% and 7 females (10 hips) 25% with age range of 5 years - 65 years with mean age of 41.32 ± 18.50 years out of which males were from 5 - 65 years with mean age 40.86 ± 20.44 and females were in the age range of 23 - 52 years with mean age 42.71 ± 12.04. Out of 28 patients 9 (32.14%) were FAI, 8 (28.57%) were OA hip, 8 (28.57%) were Avascular necrosis of Femoral head and 3 case (10.71%) is of Perthes' disease. In FAI cases 4(44.44%) patients were of Pincer type, 5(55.55%) were of Combined type with no any case of isolated CAM form. All were unilateral involvement with average CE angle of 32.67 ° ± 11.67 °. In Pincer type mean CE angle was 36.25 ° ± 7.5 ° while in combined form the mean CE angle was 29.8 ° ± 14.4 °. Out of 4 patients of Pincer FAI, 3 patients of Pincer type had CE angle between 25 - 40 ° which comes under normal range of CE angle so all were planned for non-operative management. Conclusions: We have found that all the hip pathologies reported to us had spectrum of variations in CE angle depending on the severity of disease. Variation was maximum seen in Osteoarthritis and Femoroacetabular impingement, in the cases of FAI maximum were of Pincer type.

Hip morphology in slipped capital femoral epiphysis.

Several mechanical factors have been related to slipped capital femoral epiphysis (SCFE). Main aim of this study is to investigate the acetabular coverage and acetabular version in unilateral SCFE hips in order to detect a potential pincer-type deformity as predisposing factor; second, we compared those measurements either to the contralateral, uninvolved hips either to a matched healthy control population. A total of 85 patients treated for unilateral SCFE were retrospectively reviewed. The lateral center-edge angle (LCEA) and the Tönnis angle were used to assess acetabular coverage, whereas acetabular retroversion was defined by positive prominent ischial spine (PIS), cross-over sign (COS) and posterior wall sign (PWS). Angles and signs of the affected hips were compared to the contralateral hips and to a matched cohort undergoing an abdominal/pelvic computed tomography for nonorthopedic-related diseases. Affected and unaffected hips of patients with unilateral SCFE had similar morphology in terms of LCEA 28.7° vs. 28° (P = 0.4), Tönnis angle 9° vs. 9° (P = 0.1) and retroversion signs with concomitant rate of PWS and COS 57.6% vs. 50.5% (P = 0.4), PIS 56.4% vs. 49.4% (P = 0.4). Matched healthy controls vs. the affected hips showed a lower LCEA (P < 0.001) and higher Tönnis angle (P < 0.001) in conjunction with a lower incidence of acetabular retroversion: PWS and COS 40% vs. 57.6% (P = 0.01), PIS 43% vs. 56.4% (P = 0.07). A significant retroversion and increased overcoverage were observed in SCFE patients compared to matched healthy controls. In unilateral SCFE, the involved and uninvolved hips showed a substantial symmetry.

Periacetabular triple osteotomy by single anterior approach for children under 6-years-old with severe acetabular deficiency: prevention of retroversion and anterior impingement.

The aim of this study was to perform periacetabular triple osteotomy (PATO) in children under 6-years-old with severe acetabular deficiency aiming to obtain important correction and avoid excessive pressure on epiphysis, anterior overcorrection and acetabular retroversion. This is a retrospective study of 29 PATO using single anterior approach in 24 patients under 6-years-old with dysplasia of the hip. Clinical examination and radiographic evaluation were done pre-op, post-op and at last follow-up. Computed tomography (CT) scan was obtained, comparing operated hip to contro-lateral normal hip. Clinical examination of the operated hip, at the last follow-up, showed a normal range of motion with nonsignificant difference when compared to normal hip. All hips were classified as Wicart A, and all activities were allowed. Radiographically, X-ray revealed improvement of all parameters postoperatively, with nonsignificant change compared to the last follow-up. CT-2D axial analysis demonstrated the absence of acetabular retroversion with good anterior and posterior coverage. CT-3D imaging comparing the anterior acetabular inclination, anterolateral and posterolateral inclination angles of operated hip and normal hip showed comparable results. Patients less than 6 years with severe acetabular deficiency could benefit from PATO. Performing osteotomies close to joint gave important acetabular fragment freedom, allowing an important correction. Appropriate manoeuver of reorientation avoided anterior overcorrection and acetabular retroversion, responsible for early pain and osteoarthritis. Age should not be the only criteria to choose the type of osteotomy. Level of evidence: level IV.

Volumetric and acetabular changes in the bony pelvis associated with primary closure of classic bladder exstrophy

Repair of classic bladder exstrophy (CBE) is known to alter dimensions of the bony pelvic ring. Pelvic volume and acetabular configuration are additional metrics which merit analysis in the reconstruction process. Advances in magnetic resonance imaging (MRI) allow for precise elucidation of such anatomy in pediatric patients, providing enhanced knowledge of how primary reconstruction may impact factors in pelvic health. An IRB-approved exstrophy-epispadias database of 1337 patients was reviewed for patients with CBE who had pelvic MRI performed before and after repair. Pelvic MRIs were analyzed by a pediatric radiologist, and three-dimensional volumetric renderings of the true pelvis were calculated. Pre- and post-closure imaging were compared, in addition to imaging from age-matched controls without pelvic pathology. Cartilaginous acetabular index and version angles were also calculated and compared between groups. Eighteen patients with post-closure imaging, 14 of whom also had pre-closure imaging, and 23 control patients (ages 0-365 days) were included. The median ages at pre- and post-closure scan were 2 and 178 days, respectively. Osteotomy was performed in 6 (33%) of the closures. The median segmented pelvic volumes were 89cm3 in the pre-closure group, 105cm3 in the post-closure group, and 72cm3 in the control group. At a given age, patients with CBE pre-closure had the largest pelvic volume, and those without bladder exstrophy demonstrated the smallest pelvic volumes (Summary Figure). CBE patients' pelvic volumes were overall lower following repair, relative to age (p=0.007). Cartilaginous acetabular version angle increased following closure, with acetabular orientation converting from retroversion to anteversion in all cases. However, only acetabular version angles were significantly different between groups. This study found that pelvic volume significantly decreased relative to age following primary repair of CBE, but that it did not correct to control levels. Similarly, acetabular retroversion that is naturally seen in exstrophy patients was converted to anteversion post-closure but did not become completely normal. Knowledge of these persistent anatomical anomalies may be useful in treatment of future concerns related to exstrophy, such as continence achievement, pelvic organ prolapse, and potential gait disturbances. Lack of significant differences between study groups regarding acetabular index angles can give assurance to providers that hip dysplasia is neither a natural concern nor iatrogenically inflicted through reconstruction. The primary closure of exstrophy results in pelvic volumes and anteverted acetabula that more closely resemble those without bladder exstrophy, compared to pre-closure findings.

Pelvic motion the key to understanding spine-hip interaction.

Pelvic motion acting as a hinge between the spine and hips is essential to maintain proper balance during bipedalism. Pelvic rotation is recruited as a compensation mechanism when spinal malalignment occurs.This pelvic rotation can affect functional acetabular orientation, and consequently functional cup positioning if a total hip arthroplasty (THA) is needed. Pelvic retroversion, frequently associated with degenerative spinal changes, implies an increase of acetabular version.Patients with flexible lumbar spines (spine users) protect the hip joint. Patients with stiff, degenerated or fused lumbar spines (hip users) demand higher hip mobility, placing the THA at risk.Pelvises in retroversion place the THA at risk for anterior dislocation when standing. In contrast, pelvises in anteversion or with low pelvic incidence (PI) can place THA at risk for posterior dislocation when sitting.Try to set the cup in an anatomic position. However, bear in mind that low PI pelvises may need more acetabular ante-inclination, and high PI pelvises more acetabular retroversion.If surgery is needed, start first by addressing the hip, except in patients with compensation (high pelvic retroversion), who may need spine surgery first to place the pelvis, and consequently the acetabulum, in a proper position.Cite this article: EFORT Open Rev 2020;5:522-533. DOI: 10.1302/2058-5241.5.200032

A home-based exercise and activity modification program in patients with acetabular retroversion and excessive anterior pelvic tilt

A home-based exercise and activity modification program in patients with acetabular retroversion and excessive anterior pelvic tilt

The Ischial Spine in Developmental Hip Dysplasia: Unraveling the Role of Acetabular Retroversion in Periacetabular Osteotomy.

Purpose Radiological diagnosis of acetabular retroversion (AR) is based on the presence of the crossover sign (COS), the posterior wall sign (PWS), and the prominence of the ischial spine sign (PRISS). The primary purpose of the study is to analyze the clinical significance of the PRISS in a sample of dysplastic hips requiring periacetabular osteotomy (PAO) and evaluate retroversion in symptomatic hip dysplasia. Methods In a previous paper, we reported the classic coxometric measurements of 178 patients with symptomatic hip dysplasia undergoing PAO where retroversion was noted in 42% of the cases and was not found to be a major factor in the appearance of symptoms. In the current study, we have added the retroversion signs PRISS and PWS to our analysis. Among the retroverted dysplastic hips, we studied the association of the PRISS with the hips requiring PAO. We also defined the ischial spine index (ISI) and studied its relationship to the coxometric measurements and AR. Results In hips with AR, the operated hips were significantly associated with the PRISS compared to the nonoperated ones (χ2 = 4.847). Additionally, the ISI was able to classify acetabular version (anteverted, neutral, and retroverted acetabula). A direct correlation between the ISI and the retroversion index (RI) was found, and the highest degree of retroversion was found when the 3 signs of acetabular retroversion were concomitantly present (RI = 33.6%). Conclusion The PRISS, a radiographic sign reflecting AR, was found to be significantly associated with dysplastic hips requiring PAO where AR was previously not considered a factor in the manifestation of symptoms and subsequent requirement for surgery. Moreover, the PRISS can also serve as an adequate radiographic sign for estimating acetabular version on pelvic radiographs.

Borderline Dysplasia with Acetabular Retroversion: Key Findings from a Large Hip Arthroscopy Study Group

Objectives:The radiographic crossover sign (COS) is an indicator of acetabular retroversion, classically representing anterosuperior overcoverage often treated with acetabuloplasty which could exacerbate acetabular hypovolemia in dysplasia. No prior study has investigated the prevalence of acetabular retroversion in patients with dysplasia undergoing hip arthroscopy, acetabuloplasty rates, and outcomes in this setting.Study objectives are to report the prevalence of acetabular retroversion in dysplasia, the influence of the COS on arthroscopic acetabuloplasty rates, and relative outcomes compared with control groups.Methods:A retrospective cohort study was performed from a prospectively collected multi-center database. Patients undergoing isolated hip arthroscopic surgery were assigned to dysplasia (lateral center-edge angle (LCEA) ≤ 25°) or one of two control groups: normal(LCEA 26-38°), or pincer femoroacetabular impingement (FAI)(LCEA ≥ 39°). The prevalence of COS and acetabuloplasty rates between and within study and control groups were compared (Chi square analysis). Minimum 2 year outcomes utilizing iHOT-12 were compared (analysis of variance).Results:Of 401 study patients, 64 (16%) comprised the dysplasia group, 273 (68%) normal group, and 64 (16%) pincer group. Mean LCEAs were 22.3°, 31.5°, and 42.4°, respectively (p<0.001). COS prevalence was similar between groups at 31%, 26%, and 33%, respectively (p=0.873). Acetabuloplasty rates were dependent on the amount of acetabular coverage with lowered rate in the dysplasia group(40%) and increasing rates in the normal(52%) and the pincer(90%) groups (p=0.013). Post-operative iHOT-12 scores improved in all groups (68, 74, and 77, respectively, p=0.222). Patients with a COS plus rendered acetabuloplasty reported similar scores that improved to 77, 74, and 79, respectively,(p=0.949). Patients with dysplasia with COS averaged 73.1(SD 23.3) iHOT-12 score compared to 67.1(SD: 28.7) for the patients with dysplasia without COS (p=0.466). Within the dysplasia with COS subgroup, there was no significant difference in iHOT-12 scores between the group with acetabuloplasty (77.0;SD:17.1) and without acetabuloplasty (70.4;SD:27.4,p=0.580).Conclusion:Acetabular retroversion occurs with similar prevalence in borderline dysplasia compared with non-dysplastic hips undergoing hip arthroscopy but with lower acetabuloplasty rates not influenced by the COS. Arthroscopic outcomes of dysplasia with retroversion are similarly successful and comparable with those of dysplasia and non-dysplastic hips. Although infrequently performed, acetabuloplasty did not compromise outcomes in dysplasia with retroversion.

Patient-related risk factors associated with less favourable outcomes following hip arthroscopy.

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. Assessment of these texts yielded 101 final articles involving 90,315 hips for qualitative analysis. The most frequently reported risk factor related to a less favourable outcome after hip arthroscopy was older age and preoperative osteoarthritis of the hip. This was followed by female sex and patients who have low preoperative clinical scores, severe hip dysplasia, altered hip morphology (excess acetabular retroversion or excess femoral anteversion or retroversion), or a large cam deformity. Patients receiving workers' compensation or with rheumatoid arthritis were also more likely to have a less favourable outcome after hip arthroscopy. There is evidence that obesity, smoking, drinking alcohol, and a history of mental illness may be associated with marginally less favourable outcomes after hip arthroscopy. Athletes (except for ice hockey players) enjoy a more rapid recovery after hip arthroscopy than non-athletes. Finally, patients who have a favourable response to local anaesthetic are more likely to have a favourable outcome after hip arthroscopy. Certain patient-related risk factors are associated with less favourable outcomes following hip arthroscopy. Understanding these risk factors will allow the appropriate surgical indications for hip arthroscopy to be further refined and help patients to comprehend their individual risk profile. Cite this article: Bone Joint J 2020;102-B(7):822-831.