Search

This is a unique clinical case of a spontaneous non-traumatic hip dislocation in a patient with stroke with a hip and knee flexion pattern. This case highlights the role of spasticity as a cause of hip dislocation and the need to combine focal spasticity treatment and surgery to restore ambulation.

Excision of acetabular osteoid osteoma is technically difficult. We report osteoid osteoma of the quadrilateral plate in a 9-year-old girl who presented to us with persistent nocturnal pain, limp and restricted hip joint movement. The child was investigated with CT scan, MRI and triple-phase bone scan. The 0.7 cm nidus was located in the central portion of the cancellous bone in the quadrilateral plate, 1.94 cm inferior to the triradiate cartilage. The child was operated on through the safe surgical dislocation of the left hip. The location of the lesion was gauged from the preoperative CT scan measurement data and intraoperative fluoroscopic aid. The nidus with a sclerotic rim was burred down completely. Postoperative X-ray and CT scan revealed complete excision of the tumour, and the patient was pain-free. At 18 months follow-up, the patient is completely asymptomatic and walking normally.

To provide further clarity regarding the management of patients with abnormal femoral version in the setting of hip arthroscopy and will discuss the definition of femoral version, the diagnostic and clinical evaluation of abnormal femoral version, and several described measurement techniques.A systematic review was conducted in literature published before August 2021 that measured femoral version and reported patient-reported outcomes measures or rates of subsequent procedures following hip arthroscopy. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed and the electronic databases, PubMed, OvidMedLine, Scopus, and Web of Science were searched. Two blinded reviews screened and evaluated data quality using the Newcastle-Ottawa Scale.Eighteen studies were included with 11 studies reporting patient outcomes and 7 studies reporting rates of subsequent procedures. The most commonly used definition of femoral version was 5° to 20° of femoral anteversion. Computed tomography scan was the most commonly used imaging modality. The majority of studies (7 of 11) demonstrated that femoral version does not have an impact on patient-reported outcomes measures and is not predictive of clinically meaningful improvement scores. However, in select studies, patients with femoral retroversion were found to experience slightly inferior outcomes following hip arthroscopy for femoroacetabular impingement. While femoral retroversion may be a risk factor for subsequent procedures, 3 of 7 studies refute this claim. Although in patients with borderline hip dysplasia, excessive femoral anteversion led to greater rates of subsequent hip procedures.While the majority of studies show that femoral version does not have an impact on patient-reported outcomes following hip arthroscopy, those with femoral retroversion and with excessive anteversion with coexisting borderline hip dysplasia need to be educated on their increased risk of subsequent operation. Ultimately, this review suggests that clinical improvement can likely be achieved regardless of femoral version.IV; systematic review of Level I-IV studies.

Despite the remarkable success of total hip arthroplasty as treatment of arthritis of the hip, complications can still occur, and imaging plays a crucial role for both diagnosis and guiding management. Component dislocation in total hip arthroplasty is usually diagnosed on radiographs, but cross-sectional imaging is necessary to quantitatively assess component orientation which may have predisposed to the dislocation. The definitive sign of component loosening on radiography is progressive motion of the component, but CT will provide more osseous detail and recent studies have shown the role of MRI in assessing component loosening as well. Infection is a devastating complication for which early diagnosis is crucial. Radiographs are not sensitive for infection, but there are certain MRI features that can suggest infection, and ultrasound and fluoroscopy are useful for guiding arthrocenteses to diagnose infection. Tendon and neurovascular injuries can be a source of long-term disability after total hip arthroplasty, and radiological studies, particularly advanced cross-sectional imaging such as MRI and ultrasound, often play an important role in their diagnoses.

The purpose of this study is to determine whether there is a higher dislocation rate when postoperative hip precautions are not used for primary total hip arthroplasty (THA).A survey was conducted of the hip precautions used by orthopaedic departments in England performing elective primary THA. From the responses to the survey an interrupted time series analysis was performed using the hospital admissions data from the Hospital Episode Statistics (HES) database during the period April 1, 2011 to December 31, 2019 and subsequent dislocations of these prostheses up to June 30, 2020. These were used to determine dislocations within 180 days of primary surgery and emergency readmissions within 30 days of discharge.Records were reviewed from 229,057 patients receiving primary, elective THA across 114 hospitals. In total, 1,807 (0.8%) dislocations were recorded within 180 days of surgery. There were 12,416 (5.4%) emergency readmissions within 30 days of surgery. Within hospitals where hip precautions were stopped, the proportion of patients having a dislocation was 0.8% both before and after stopping precautions, with a significant postintervention trend towards fewer dislocations (P.001). There was also a significant immediate change in median length of stay from 4 to 3 days (P.001) but no significant trend in the proportion of emergency readmissions within 30 days.There is no evidence of an increase in early dislocation or 30-day readmission rates after stopping traditional postoperative hip precautions in primary THA. Potential reductions in length of stay will reduce the risks associated with an extended hospital admission, improve service efficiency, and reduce costs.

BACKGROUND: Developmental dysplasia of the hip (DDH) is the most common musculoskeletal abnormality in infants and young children. Despite the fact that the left hip is most frequently affected, literature and clinical experience suggest a poorer outcome for right-sided hip dislocation in DDH. On the basis of this hypothesis, we studied the outcomes (residual dysplasia, number of surgeries, and complication rate) of right-sided unilateral hip dislocation in comparison with left-sided unilateral hip dislocation in DDH up to 8 years follow-up. METHODS: We identified all patients with unilateral hip dislocation at Erasmus MC Sophia Children's Hospital from 2002 to 2012, diagnosed with DDH before the age of 1 year and with a minimum follow-up of 8 years. The primary outcome was residual dysplasia (based on an acetabular index (AI) >18 degrees and center-edge angle of Wiberg (CEA)

Background: The lateral center-edge angle of Wiberg (LCEA) and Tönnis angle (TA) rely on a “horizon” that functions as a reference point for measurements of hip dysplasia on weightbearing anteroposterior pelvis radiographs. There are 3 different horizons that are currently utilized depending on surgeon preference: (1) a line parallel to the radiographic floor (F), (2) a line that connects the inferior portions of the acetabular teardrops (ATs), or (3) a line that connects the ischial tuberosities (ITs). It is imperative to accurately assess the degree of hip dysplasia on initial workup to select the appropriate surgical intervention. Purpose: To assess how the choice of a radiographic horizon affects the measurements of the LCEA and TA. The secondary purpose was to assess how the horizon affected the classification of hips as either normal, borderline dysplastic, or dysplastic. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: The LCEA and TA were measured on all preoperative weightbearing anteroposterior pelvis radiographs for 186 consecutive patients who underwent hip preservation surgery between February 2016 and November 2020 (140 hip arthroscopic procedures, 46 combined hip arthroscopic procedures with periacetabular osteotomy), 3 times per hip, each time using an F, AT, and IT horizon. The Student t test was used to analyze the differences in the measurements of the LCEA and TA, and discordance rates in the dysplasia classification between horizons were quantified. Results: For the entire study population, the mean LCEAF (23.4°± 7.4°) was significantly greater than the mean LCEAIT (23.1°± 7.2°) (95% CI, −0.634 to −0.003; P = .047) and mean LCEAAT (23.0°± 7.1°) (95% CI, −0.723 to −0.139; P = .004). There was no difference between the LCEAIT and LCEAAT (95% CI, −0.305 to 0.080; P = .251). When stratified by hip arthroscopic surgery, the mean LCEAF (26.3°± 5.6°) was significantly greater than the mean LCEAAT (25.8°± 5.3°) (95% CI, −0.845 to −0.162; P = .004). Overall, there was a 17.7% and 18.3% discordance rate in the dysplasia classification using the LCEAIT and LCEAAT compared with the LCEAF, respectively. There were no statistically significant differences between the mean TAIT, TAAT, and TAF for the entire study population, the arthroscopic surgery group, and the combined arthroscopic surgery and periacetabular osteotomy group. Conclusion: There was no statistical difference between the AT and IT horizons for LCEA measurements. The dysplasia classification was in better agreement between the 2 anatomic horizons compared with the F horizon. The TA was not affected by changes in the horizon.

Aims Dislocation of the hip remains a major complication after periacetabular tumour resection and endoprosthetic reconstruction. The position of the acetabular component is an important modifiable factor for surgeons in determining the risk of postoperative dislocation. We investigated the significance of horizontal, vertical, and sagittal displacement of the hip centre of rotation (COR) on postoperative dislocation using a CT-based 3D model, as well as other potential risk factors for dislocation. Methods A total of 122 patients who underwent reconstruction following resection of periacetabular tumour between January 2011 and January 2020 were studied. The risk factors for dislocation were investigated with univariate and multivariate logistic regression analysis on patient-specific, resection-specific, and reconstruction-specific variables. Results The dislocation rate was 13.9% (n = 17). The hip COR was found to be significantly shifted anteriorly and inferiorly in most patients in the dislocation group compared with the non-dislocation group. Three independent risk factors were found to be related to dislocation: resection of gluteus medius (odds ratio (OR) 3.68 (95% confidence interval (CI) 1.24 to 19.70); p = 0.039), vertical shift of COR > 18 mm (OR 24.8 (95% CI 6.23 to 128.00); p = 0.001), and sagittal shift of COR > 20 mm (OR 6.22 (95% CI 1.33 to 32.2); p = 0.026). Conclusion Among the 17 patients who dislocated, 70.3% (n = 12) were anterior dislocations. Three independent risk factors were identified, suggesting the importance of proper restoration of the COR and the role of the gluteus medius in maintaining hip joint stability. Cite this article: Bone Joint J 2022;104-B(10):1180–1188.

The study's aim was two-fold: to describe the trend of hip subluxation in the largest sample of Italian nonambulatory cerebral palsy (CP) children ever published; to investigate its determinants. This single-centre retrospective cohort study included patients with spastic or dyskinetic CP, Gross Motor Function Classification System (GMFCS) level IV or V, age 0-18 years, having been referred to our unit before March 2020. The hip subluxation was measured by means of the migration percentage (MP). Other data were gathered such as sex, CP subtype, GMFCS level, presence of drug-resistant epilepsy, age, use of walkers with weight relief or standing devices, previous botulinum injection or hip surgery, oral or intrathecal baclofen and hip pain. Multiple linear stepwise regression was performed and descriptive statistics are provided. Spastic CP had MP maximum increase in early ages, with GMFCS level V values persistently higher than level IV. The dyskinetic subtype showed a slower increase of the MP, with GMFCS level IV presenting similar or higher values, compared to level V. Age, CP severity and spastic subtype are the main determinants. The stepwise multiple regression analysis demonstrated that weight relief walking and standing assistive devices, combined with botulinum contributed to reduce the MP progression. Dyskinetic CP showed overall lower MP values and a more variable behaviour relative to age and GMFCS level, compared to the spastic subtype. Standing and walking assistive devices, with partial or total weight relief, combined with individually targeted botulinum injections, should be considered in the management of bilateral nonambulatory CP patients, to prevent hip subluxation or its recurrence after surgery.

To investigate the clinical and radiological results of revision total hip arthroplasty (THA) for patients with previously diagnosed Hartofilakidis type C hip dysplasia, which is technically challenging and lacks literature.We enrolled 20 patients with previously diagnosed Hartofilakidis type C hip dysplasia who underwent revision THA between November 2008 and July 2015 at our hospital. Patients were followed up for an average of 87 months. Data pertaining to the Harris hip score (HHS), modified Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), general satisfaction, and the level of satisfaction related to 16 hip functions or issues experienced after revision THA were collected. The vertical and horizontal center of rotation (COR) of the hips were measured bilaterally based on preoperative and postoperative anteroposterior radiographs. Categorical variables were analyzed by the chi-square test. Continuous variables were analyzed using the student's t test or non-parametric Wilcoxon Rank Sum test.There were significant postoperative improvements in the HHS (47.4 ± 31.6 vs 70.1 ± 39.0), modified WOMAC (48.5 ± 27.9 vs 75.7 ± 36.8), and the vertical (45.7 ± 33.7 mm vs 21.6 ± 21.8 mm) and horizontal (41.8 ± 17.0 mm vs 31.4 ± 14.7 mm) offset of the COR after revision THA (P 0.05). Fifteen (75.0%) patients were satisfied with the procedure. The satisfaction rate for each of the 16 items ranged from 45% to 100%. The top three dissatisfactory items were squatting, getting into/out of cars, and leg-length discrepancy. Postoperatively, dissatisfied patients had a significantly higher visual analogue scale pain score and lower WOMAC pain, HHS pain, WOMAC total, and HHS total scores, a lower satisfaction rate for pain relief, and a higher vertical COR.There is a high rate (25%) of dissatisfaction with the outcome after revision THA for patients with prior Hartofilakidis type C hip dysplasia. The most likely reasons for dissatisfaction were inadequate pain relief and a higher vertical COR measured on radiography.

Objective: This article explores the potential care provided to a middle-aged man who had a suite of injuries evident in his skeleton, most notably an obturator fracture dislocation in his left hip. Materials: The skeleton derived from the Late Medieval Gaelic population buried at Ballyhanna, Co. Donegal, Ireland.Methods: A transdisciplinary bioarchaeology of care approach was adopted to undertake a phenomenological study of an individual with an acquired disability. Results: The man would have required intensive nursing care in the months following the initial injury, and longer-term accommodations may have been made by the wider community to support him. Conclusions: Use of a transdisciplinary bioarchaeology of care approach enables important insights to be gained concerning the social impact of disability on the affected individual, his kin, and wider community.Significance: This study achieves a new level of integration of bioarchaeological findings with archaeological, historical, and ethno-historical sources, thereby enabling a phenomenological approach to interpretation of life after acquired disability. This is the first study to allow such an intimate insight into lived experience and it provides a model for bioarchaeology of care analysis of individuals from historical eras.Limitations: These iInclude difficulties in identifying the nature of a long-standing complex injury.Suggestions for future research: Further explorations of the bioarchaeology of care in historical time periods should incorporate a similarly wide range of transdisciplinary sources to enrich interpretations of the lived experiences of individuals, their care-givers and broader communities.

To report minimum 2-year follow-up patient-reported outcomes and return-to-sport (RTS) rates in athletes undergoing concomitant hip arthroscopy and periacetabular osteotomy (PAO) to treat acetabular dysplasia and intra-articular pathologies such as cam deformity and labral tears.We reviewed the data of consecutive athletes undergoing concomitant primary hip arthroscopy and PAO for acetabular dysplasia and cam deformity from November 2010 to December 2018. Patients were included in the study if they had the following preoperative and minimum 2-year postoperative scores: modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), and Hip Outcome Score-Sport-Specific Subscale (HOS-SSS). The percentage of patients who achieved the minimal clinically important difference was recorded, in addition to RTS status.A total of 29 athletes (29 hips) were included, with a mean follow-up time of 34.1 ± 7.9 months, mean age of 26.0 ± 8.7 years, and mean body mass index of 23.7 ± 3.4. These athletes showed significant improvements in the mHHS, NAHS, and HOS-SSS from baseline to latest follow-up (P.001). The minimal clinically important difference was achieved at high rates for the mHHS (82.8%), NAHS (86.2%), and HOS-SSS (79.3%). Athletes who attempted to RTS successfully returned at a rate of 81.8%.Athletes undergoing concomitant hip arthroscopy and PAO showed significant improvements in patient-reported outcomes at minimum 2-year follow-up and had an RTS rate of 81.8%.Level IV, retrospective case series.

Periacetabular osteotomy (PAO) is an effective joint-preserving procedure for developmental dysplasia of the hip. However, some patients report dissatisfaction after PAO. Because patient satisfaction is increasingly used as a health care quality metric, it is important to gain a better understanding of factors associated with patient satisfaction after PAO. The goal of this study was to investigate patient satisfaction among a cohort of Asian patients undergoing PAO. This study included 227 Asian patients who had undergone PAO at our institution between 1998 and 2016. The study participants completed a questionnaire assessing patient satisfaction, reasons for dissatisfaction, and postoperative Oxford Hip Score (OHS) and University of California, Los Angeles (UCLA), activity scale score. Based on their satisfaction levels, the participants were divided into 4 subgroups, and their demographic characteristics and postoperative patient-reported outcomes were compared. Of the 227 patients, 190 expressed satisfaction that correlated with OHS-pain, OHD-activities of daily living, and UCLA activity scale scores. Primary reasons for dissatisfaction after PAO were persistent pain (24 of 49, 49%), functional limitations (14 of 49, 29%), stiffness around the hip (4 of 49, 8%), unmet expectations (4 of 49, 8%), conversion to total hip arthroplasty (2 of 49, 4%), and complications (1 of 49, 2%). Multivariate analysis showed that preoperative Kellgren-Lawrence grades 1 and 3 were the significant predictive factors for satisfaction and dissatisfaction, respectively. The potential for lower patient satisfaction associated with Kellgren-Lawrence grade 3 because of persistent pain and functional limitations postoperatively suggests that consideration of preoperative severity of osteoarthritis could enhance patient satisfaction after PAO. [ Orthopedics . 2022;45(5):297–303.]

Salter innominate osteotomy (SIO) provides favorable results for treating residual acetabular dysplasia in young children. In this study, we examined the midterm results of SIO according to the age at surgery to determine the optimal timing of this procedure.We retrospectively examined 50 hips of 42 patients (8 boys and 34 girls) with acetabular dysplasia who underwent SIO and were followed up until skeletal maturity. The center-edge angle (CEA) was measured based on the anteroposterior radiographs of the hip obtained before surgery, 5 weeks after surgery, and at the latest follow-up. Severin classification was evaluated at the latest follow-up. Patients were categorized into 3 groups according to age at surgery: younger than 7 years of age (group A), 7 to 8 years of age (group B), and 9 years of age or older (group C).The mean preoperative CEA level of 0.9 degrees improved to 17.1 degrees postoperatively, which was increased to 28.1 degrees at the latest examination. Overall, 45 hips (90%) were classified as Severin I or II, with 96% in group A, 94% in group B, and 57% in group C. In group C, postoperative acetabular coverage was similar to that in the other groups (16.6 degrees in group A, 14.8 degrees in group B, and 18.1 degrees in group C), although the final outcome was unsatisfactory. The average improvement in CEA from postoperative to skeletal maturity was significantly smaller in group C than in the other groups (12.7 degrees in group A, 11.3 degrees in group B, and 3.0 degrees in group C).SIO showed favorable outcomes with satisfactory acetabular coverage at skeletal maturity. However, satisfactory acetabular coverage could not be obtained in some older patients because of limited postoperative remodeling capacity and smaller secondary improvement of CEA. We recommend that SIO should be performed in patients aged 8 years or younger.Level III-retrospective comparative study.

Hip precautions are traditionally employed after posterior total hip arthroplasty (THA). The primary purpose was to investigate the necessity of hip precautions after posterior approach THA. We hypothesized that eliminating precautions in patients that achieved appropriate intraoperative stability would not increase the dislocation rate.Randomized controlled trial of 346 consecutive eligible patients undergoing primary THA with a mean follow-up of 2.3 years (range 11 months to 3.7 years).lumbar fusion, scoliosis, abductor insufficiency, inability to achieve intraoperative stability with combined 90° flexion and 45° internal rotation in 0° adduction. Fisher's exact test was used to compare dislocation rates between the hip precaution (HP) control group and no hip precaution (NP) study group. In addition, Mann-Whitney U test was used to compare differences in HOOS JR scores at 2, 6, 12 weeks between groups.The dislocation rate was not increased in the NP (0/172: 0%) group compared to the HP group 4/174 (2.29%) (P = .418). All dislocations occurred in the precautions group, two of which required revision. There were no differences in mean HOOS Jr. scores at any 2, 6, or 12 weeks (P.05 at all timepoints) (secondary outcome).Eliminating hip precautions in patients undergoing posterior approach THA that achieve 90°/45°/0° intraoperative stability does not increase the rate of dislocation. In fact, every dislocation occurred in patients receiving hip precautions. Short-term patient-reported outcome measures were not affected by hip precautions. Surgeons may discontinue the use of hip precautions as the standard of care in patients achieving 90°/45°/0° stability.

The acetabular morphology varies greatly among individuals, and hypoplasia is more common in Asia than in Europe. Dislocation after bipolar hip arthroplasty (BHA) for femoral neck fracture occurs at a constant rate, and is affected by the acetabular morphology. This study aimed to clarify individual differences in the acetabula of Asian patients with displaced femoral neck fractures.Fifty patients with displaced femoral neck fractures were assessed (50 fractured hips, 50 non-fractured hips). On CT corrected by the anterior pelvic plane, the 100 hips were assessed regarding acetabular coverage (six parameters), acetabular depth (two parameters), and acetabular opening angle (four parameters). Additional parameters related to the fracture and sex were examined. The percentile of each parameter was shown for all hips.There was no patient with hip dysplasia defined as superior acetabular sector angle (SASA) less than 110° Compared with men, women had a significantly smaller anterior acetabular sector angle (AASA) (p = 0.016), and significantly larger acetabular inclination angle (p = 0.006) and acetabular index angle (p = 0.034). In the group with a normal SASA, seven hips (7.3%) had an anterior wall defect (AASA50°) and five hips (5.2%) had a posterior wall defect (posterior acetabular sector angle90°).Older adults with femoral neck fractures can have anterior wall and posterior wall defects, even if their SASA is normal. Hidden acetabular dysplasia may be related to post-BHA dislocation. So, our results suggest that is important to accurately evaluate the acetabulum of patients with femoral neck fracture before surgery.

Background: Validated software tools (Clinical Graphics [CG] and Hip2Norm) permit measurement of the percentage of femoral head coverage (%FHC), which aids in morphological classification and prediction of outcome after hip preservation surgery. Purpose: (1) To assess whether acetabular parameter measurements determined from 2 commonly used software systems are comparable. (2) To determine which parameters influence the correlation or differences between software outputs and measurements. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The study included 69 patients (90 hips) who underwent periacetabular osteotomy and had comprehensive preoperative imaging available. Lateral center-edge angle (LCEA), acetabular index (AI), and %FHC were determined using 3-dimensional computed tomography (CT) measurements by CG and Hip2Norm software. Images of 18 pelvises were segmented to determine spinopelvic parameters and subtended acetabular angles. Between-group measurements were compared using correlation coefficients and Bland-Altman analyses. The difference in the outputs of the 2 programs was defined as delta (Δ). Radiographic parameters were tested to assess whether they were responsible for differences in %FHC between software programs. Results: Strong correlations between LCEA (ρ = 0.862) and AI (ρ = 0.825) measurements were seen between the Hip2Norm and CG programs. However, weak correlation was seen in the estimate of %FHC (ρ = 0.358), with the presence of a systematic error. Hip2Norm consistently produced lower anterior, posterior, and total %FHC values than CG. The %FHC determined by CG, but not Hip2Norm, correlated with acetabular subtended angles ( P < .05). Pelvic tilt measured on CT did not correlate with pelvic tilt estimated by Hip2Norm ( P = .56), and ΔPelvicTilt strongly correlated with the difference in %FHC by the 2 software programs (ρ = 0.63; P = .005), pelvic incidence (ρ = 0.73; P < .001), and pelvic tilt (ρ = −0.91; P < .001) as per CT. Conclusion: The correlation of %FHC between Hip2Norm and CG was weak (ρ = 0.358). The difference in measurements of %FHC correlated with ΔPelvicTilt. The %FHC determined by CG strongly correlated with the segmented acetabular subtended angles and thus more likely reflected true values. Hip preservation surgeons should be aware of these measurement differences because %FHC is important in the diagnosis and prognosis of acetabular dysplasia.

This study aims to compare clinical and radiological follow-up results of a rectangular (SL-Plus®) or a round (Synergy®) femoral component in patients with Crowe type 2 or 3 hip dysplasia operated with total hip arthroplasty (THA) without a shortening osteotomy.Between January 2012 and December 2017, a total of 34 hips of 30 female patients (mean age: 42.9±11.6 years; range, 24 to 66 years) were retrospectively analyzed. All patients were evaluated using the Harris Hip Score (HHS) and Visual Analog Scale (VAS) for pain pre- and postoperatively. Intra- and postoperative complications were noted. Evaluation criteria included leg length discrepancy, stem subsidence, bone atrophy or hypertrophy around the stem according to Gruen zones, operative time, and intraoperative blood loss. Correlation analysis of radiological, clinical findings, and stem size was performed.The mean follow-up was 61.3±27.2 months. The mean postoperative HHS was 89.3±6.2 vs. 93.1±9.1, and the mean VAS score 1±0.6 vs. 1±0.8 in round and rectangular stem groups at the final follow-up. No significant differences were detected between the groups in any of the evaluated parameters, except for a more severe degree of stress shielding observed in the round stem group. Round stem size was positively correlated with a more severe stress shielding (r=0.55, p=0.020). No patient had to be revised during the follow-up period. The overall complication rate was 9%.Successful and comparable results can be obtained with cementless THA in patients with high riding dysplastic hips implanting either of the femoral components, a rectangular or a round stem. Although the round stem was associated with more common proximal stress shielding, this was not associated with worse clinical outcomes.

The use of dual mobility (DM) articulations has grown substantially over the last decade to help minimize dislocation risk. The purpose of this study is to compare the results of DM articulations to jumbo femoral heads of equivalent sizes as they relate to postoperative dislocation.This is a retrospective cohort study of primary total hip arthroplasties (THAs) performed at a single institution between 2005 and 2018. DM articulations and large-diameter metal-on-metal femoral heads were included. Patients were followed with Harris Hip Scores and standard radiographs. Complications were prospectively recorded. Statistical analyses included chi-squared and Brown-Forsythe tests.In total, 1,288 Magnum femoral head THAs and 365 Active Articulation DM THAs were included for analysis. The same monoblock cup was implanted via a posterior approach in all cases. Age, gender, body mass index, and diagnosis were similar between groups. Average follow-up in the DM group was 49 months, and 126 months in the jumbo head group. The average head sizes in the DM and jumbo head groups were 50 mm. There were no dislocations in the DM hips and only 2 (0.2%) in the jumbo femoral head group. Both groups had significant improvements in Harris Hip Score from their preoperative baseline.Our study found similarly low dislocation rates in DM and jumbo femoral heads in primary THA. No evidence currently exists showing a benefit of the DM articulation beyond that of the large effective head size, and we recommend making every attempt at maximizing head size prior to using DM articulations.

No prior studies have examined outcomes based on approach concordance between primary and revision total hip arthroplasty (THA). There is theoretical concern that performing surgery through multiple planes could potentiate dislocation risk. This study aimed to assess the impact of utilizing concordant vs discordant surgical approaches between primary and revision THA on incidence of dislocation, re-revision, reoperation, and nonoperative complications.Between 2000 and 2018, 705 revision THAs were retrospectively identified in patients who underwent primary THA at the same academic center. Surgical approach was determined for primary and revision THA from operative notes with dislocations, re-revisions, reoperations, and complications determined from our total joint registry. Complication rates were compared between those with concordant and discordant surgical approaches. Mean age was 65 years, 50% were female, mean body mass index was 31 kg/mSurgical approach discordance occurred in 97 cases (14%), which was more frequent when the direct anterior approach was used for primary THA (72%, P.001) compared to lateral (12%) or posterior (10%) approaches. There were no statistically significant differences in the incidence of dislocations, re-revisions, reoperations, and nonoperative complications among those with concordant and discordant approaches for the overall cohort and when analyzed by primary approach (P.05 for all).Comparable dislocation and complication rates were observed among revision THAs with concordant and discordant approaches between primary and revision THA. These data provide reassurance that changing vs maintaining the surgical approach from primary to revision THA does not significantly increase dislocation or re-revision risk.IV.

Although increased femoral head size reduces the risk of instability in total hip arthroplasty (THA), it may lead to iliopsoas irritation and increased anterior groin pain. The purpose of this study is to compare outcomes between non-modular dual-mobility (NDM) implants and small (≤32 mm) and large (≥36 mm) fixed-bearing (FB) constructs.A retrospective review of all primary total hip arthroplasties from 2011 to 2021 was conducted at a single, urban academic institution. Patients were separated into 3 cohorts: NDM implant ≤32 mm and FB implant ≥36 mm. Demographics and outcomes such as length of stay, dislocation, and anterior groin pain were assessed. Patients were deemed as having groin pain if they received an iliopsoas injection or had extended physical therapy ordered beyond 3 months postoperatively.There were 178 NDM implants, 936 ≤32-mm FB, and 2,454 ≥36-mm FB implants included. Length of stay significantly differed between the groups (48.4 ± 43.3 vs 63.2 ± 40.6 vs 57.2 ± 38.1 hours; P = .001). Although not statistically significant, the ≥36-mm FB cohort had the highest rate of dislocations (0.6% vs 0.7% vs 0.9%; P = .84). Although no patients with an NDM implant received an iliopsoas injection, 9 patients (0.9%) with a ≤32-mm FB implant and 9 patients (0.4%) with a ≥36-mm implant received an injection (P = .06). However, 18 (10.1%) patients with an NDM implant, 304 (32.5%) patients with a ≤32-mm FB implant, and 355 (14.5%) patients with a ≥36-mm FB implant received extended physical therapy 3 months after surgery (P.001).NDM implants, as well as FB implants with both small and large head sizes are effective at preventing dislocation. NDM implants did not result in an increase in anterior groin pain compared to ≤32-mm and ≥36-mm FB constructs.Retrospective cohort study.

Previous studies have demonstrated that patients with abnormal spinopelvic motion are at increased risk of dislocation. However, little is known about the effect of hip offset on dislocation risk following total hip arthroplasty (THA) in patients with abnormal spinopelvic motion. The purpose of this study is to investigate the prevalence of under-restored hip offset and spinopelvic abnormalities in a series of THA patients treated for recurrent instability.This is a retrospective review of consecutive patients treated for hip instability following primary THA (THA+I) from 2012 to 2020. Patient demographics, surgical variables, and radiographic parameters were recorded. THA+I patients were compared to an age-matched and gender-matched control THA population without hip instability (THA). Univariate analyses were performed to compare differences between groups.Thirty-three THA+I patients (44 hips) were compared to 44 THA patients (44 hips). THA+I patients had a higher prevalence of spinopelvic pathology (odds ratio [OR] 7.80, 95% confidence interval [CI] 2.59-23.50, P.001). The majority of acetabular components were placed within the Lewinnek safe zone (86.4% THA+I vs 72.7% THA; P = .119). THA+I patients were at greater risk of markedly under-restored hip offset (Δoffset ≤ 3 mm; OR 6.34, 95% CI 2.20-18.30, P = .001) and small (32 mm) femoral head diameter (OR 4.38, 95% CI 1.53-12.53, P = .006) compared to THA patients.Lumbar degenerative disease and under-restoration of hip offset were present in a high proportion of patients with hip instability. Although multiple factors may contribute to THA instability, these data suggest that restoration of offset is essential, particularly in patients with spinopelvic pathology, and may be more important than historically described acetabular targets.Level III.

Aims Patients with femoral neck fractures (FNFs) treated with total hip arthroplasty (THA) have an almost ten-fold increased risk of dislocation compared to patients undergoing elective THA. The surgical approach influences the risk of dislocation. To date, the influence of differing head sizes and dual-mobility components (DMCs) on the risk of dislocation has not been well studied. Methods In an observational cohort study on 8,031 FNF patients with THA between January 2005 and December 2014, Swedish Arthroplasty Register data were linked with the National Patient Register, recording the total dislocation rates at one year and revision rates at three years after surgery. The cumulative incidence of events was estimated using the Kaplan-Meier method. Cox multivariable regression models were fitted to calculate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the risk of dislocation, revision, or mortality, stratified by surgical approach. Results The cumulative dislocation rate at one year was 8.3% (95% CI 7.3 to 9.3) for patients operated on using the posterior approach and 2.7% (95% CI 2.2 to 3.2) when using the direct lateral approach. In the posterior approach group, use of DMC was associated with reduced adjusted risk of dislocation compared to 32 mm heads (HR 0.21 (95% CI 0.07 to 0.68); p = 0.009). This risk was increased with head sizes < 32 mm (HR 1.47 (95% CI 1.10 to 1.98); p = 0.010). Neither DMC nor different head sizes influenced the risk of revision following the posterior approach. Neither articulation was associated with a statistically significantly reduced adjusted risk of dislocation in patients where the direct lateral approach was performed, although this risk was estimated to be HR 0.14 (95% CI 0.02 to 1.02; p = 0.053) after the use of DMC. DMC inserted through a direct lateral approach was associated with a reduced risk of revision for any reason versus THA with 32 mm heads (HR 0.36 (95% CI 0.13 to 0.99); p = 0.047). Conclusion When using a posterior approach for THA in FNF patients, DMC reduces the risk of dislocation, while a non-significant risk reduction is seen for DMC after use of the direct lateral approach. The direct lateral approach is protective against dislocation and is also associated with a lower rate of revision at three years, compared to the posterior approach. Cite this article: Bone Joint J 2022;104-B(7):844–851.

Aims The aim of this study was to understand the experience of mature patients who undergo a periacetabular osteotomy (PAO), a major hip-preserving surgical procedure that treats symptomatic hip dysplasia by realigning the acetabulum. Our aim was to improve our understanding of how the operation affected the lives of patients and their families, with a long-term goal of improving their experience. Methods We used a phenomenological approach with in-depth, semi-structured interviews to investigate the experience of seven female patients, aged between 25 and 40 years, who underwent a PAO. A modified homogeneity sampling approach coupled with criterion sampling was used. Inclusion criteria involved having at least one child at home and being in a committed relationship with a spouse or partner. Results Analysis of interview transcripts revealed five major themes: feelings of frustration before having a treatment plan; fear of the operation; the importance of understanding the procedure in order to feel in control of their care; feelings of helplessness, dependence, and depression during recovery; and the need for support during recovery. Conclusion Our findings suggest that both the physical and psychosocial burdens of undergoing a PAO are great, with a major impact on the patient and their family. Many important issues lie outside the scope of what healthcare teams currently address. Cite this article: Bone Joint J 2022;104-B(7):781–785.

This study investigated the incidence of AVN in patients with cerebral palsy who underwent a hip reconstruction surgery (soft tissue release, femur and pelvic osteotomies) and its impact on quality of life.Retrospective study, with clinical and radiographic analysis of 104 patients (128 hips) GMFCS IV and V with a minimum two year follow-up. Reimers migration percentage, the amount of abduction, acetabular index, and the neck-shaft angle were collected before and after surgery. Modified Tönnis classification was used to analyze the hips before surgery, and the Bucholz and Ogden classification was used to identify hips with AVN. Function and quality of life were investigated with the CPCHILD questionnaire after surgery.The mean age of participants at surgery was 120.1 months (72-184), and it was not related with AVN (p = 0.946). AVN signs were observed in 62 hips (48.5%). The mean pre-op Reimers value was 68.7% (16-100) in normal hips and 83.1% (0-100) in hips with AVN (p = 0.003). All hips considered as Tönnis IV before surgery developed AVN (p = 0.006). The amount of abduction did not differ between hips that developed AVN and those that did not (p = 0.313). Patients who developed AVN had lower scores of quality of life (p = 0.023) and comfort (p = 0.025) according to the CPCHILD questionnaire.We observed a relationship between the greater pre-operative severity according to the Reimers index and the modified Tonnis classification and the development of AVN.

This article was updated on August 17, 2022, because of previous errors, which were discovered after the preliminary version of the article was posted online. On page 1462, in the first sentence of the Abstract section entitled "Results," the phrase that had read "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003), but more dislocations than 32-mm heads (HR for2 weeks = 2.25 [95% CI, 1.13 to 4.49]; p = 0.021)" now reads "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003) and 32-mm heads (HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88]; p = 0.021)." On page 1468, in the last sentence of the section entitled "Acetabular Components with a Diameter of51 mm," the phrase that had read "and HR for ≥2 weeks = 2.25 [95% CI, 1.13 to 4.49; p = 0.021]) ( Fig. 3 )" now reads "and HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88; p = 0.021]) ( Fig. 3 )." Finally, on page 1466, in the upper right corner of Figure 3 , under "32mm vs 36mm," the second line that had read "2Wks+: HR=2.25 (1.13, 4.49), p=0.021" now reads "2Wks+: HR=0.44 (0.22, 0.88), p= 0.021."The acetabular component diameter can influence the choice of femoral head size in total hip arthroplasty (THA). We compared the rates of revision by femoral head size for different acetabular component sizes. Data from the Australian Orthopaedic Association National Joint Replacement Registry were analyzed for patients undergoing primary THA for a diagnosis of osteoarthritis from September 1999 to December 2019. Acetabular components were stratified into quartiles by size:51 mm, 51 to 53 mm, 54 to 55 mm, and 56 to 66 mm. Femoral head sizes of 28 mm, 32 mm, and 36 mm were compared for each cup size. The primary outcome was the cumulative percent revision (CPR) for all aseptic causes and for dislocation. The results were adjusted for age, sex, femoral fixation, femoral head material, year of surgery, and surgical approach and were stratified by femoral head material. For acetabular components of51 mm, 32-mm (hazard ratio [HR] = 0.75 [95% confidence interval (CI), 0.57 to 0.97]; p = 0.031) and 36-mm femoral heads (HR = 0.58 [95% CI, 0.38 to 0.87]; p = 0.008) had a lower CPR for aseptic causes than 28-mm heads; and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003), and 32-mm heads (HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88]; p = 0.021). For 51 to 53-mm, 54 to 55-mm, and 56 to 66-mm-diameter acetabular components, there was no difference in the CPR for aseptic causes among head sizes. A femoral head size of 36 mm had fewer dislocations in the first 2 weeks than a 32-mm head for the 51 to 53-mm acetabular components (HR for2 weeks = 3.79 [95% CI, 1.23 to 11.67]; p = 0.020) and for the entire period for 56 to 66-mm acetabular components (HR = 1.53 [95% CI, 1.05 to 2.23]; p = 0.028). The reasons for revision differed for each femoral head size. There was no difference in the CPR between metal and ceramic heads. There is no clear advantage to any single head size except with acetabular components of51 mm, in which 32-mm and 36-mm femoral heads had lower rates of aseptic revision. If stability is prioritized, 36-mm femoral heads may be indicated. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Objectives The aim of this study was to investigate the degree to which conventional radiography can represent the acetabular and femoral rotational alignment profile between dysplastic and borderline-dysplastic hips. Methods A retrospective trial was conducted including 56 borderline-dysplastic and dysplastic hips at a mean age of 28.9 years (range from 18 to 46). Inclusion criteria consisted of symptomatic patients with hip dysplasia undergoing 2-dimensional radiography as well as computed tomography. On radiography, the lateral center edge angle, acetabular hip index, hip lateralization index, acetabular index angle, and the Sharp angle were measured, and the presence of a crossover sign was noted. In computed tomography, the full rotational profile of the lower limb was measured. Results Significant correlations were observed in the overall analysis between the anteversion of the acetabulum and the hip lateralization index (mean 0.56, coefficient of regression (CoR) −32.35, p = 0.011) as well as the acetabular index angle with a mean of 11.50 (CoR 0.544, p = 0.018). Similar results were found in the subgroup of dysplastic hips with an acetabular index angle of 13.9 (p = 0.013, CoR 0.74). For the borderline-dysplastic group, no significant correlations between the pelvis radiography and rotational CT were seen. Conclusion Although the femoral and acetabular torsion cannot be predicted from x-rays, the anteversion of the acetabulum correlates with the acetabular index angle, the hip lateralization index, and eventually the beta angle in dysplastic hips. For borderline-dysplastic hips, such results did not show up, which strongly illustrates the need for computed tomography in these cases. Key Points • Much of the current literature focuses on rotational alignment especially with respect to the femur and tibia in healthy patients, although little is known about the acetabular, femoral, and tibial torsion in dysplastic hips. • This is the first study showing significant correlations between the anteversion of the acetabulum and the hip lateralization index as well as the acetabular inclination angle. Also, it is the first study to provide a mechanism for estimation of the torsion of the acetabulum with plain radiography in dysplastic hips. • In borderline-dysplastic hips, no significant correlation was found, which raises the question if a simple x-ray has enough validity to address the acetabular deformity with surgery.

Robotic-assistance total hip arthroplasty (RA-THA) and computer navigation THA (CN-THA) have been shown to improve accuracy of component positioning compared to manual techniques; however, controversy exists regarding clinical benefit. Moreover, these technologies may expose patients to risks. The purpose of this study is to compare rates of intraoperative fracture and complications requiring reoperation within 1 year for posterior approach RA-THA, CN-THA, and THA with no technology (Manual-THA).In total, 13,802 primary, unilateral, elective, posterior approach THAs (1770 RA-THAs, 3155 CN-THAs, and 8877 Manual-THAs) were performed at a single institution between 2016 and 2020. Intraoperative fractures and reoperations within 1 year of the index procedure were identified. Cohorts were balanced using inverse probability of treatment weight based on age, gender, body mass index, femoral cementation, history of spine fusion, and Charlson Comorbidity Index. Logistic regression was performed to create odds ratios for complications. Additional regression analysis for dislocation was performed, adjusting for dual mobility and femoral head size.There were no differences in intraoperative fracture and postoperative complication rates between the groups (P = .521). RA-THA had a 0.3 odds ratio (95% confidence interval 0.1-0.9, P = .046) compared to Manual-THA for reoperation due to dislocation. CN-THA had an odds ratio of 3.0 for reoperation due to dislocation (95% confidence interval 0.8-11.3, P = .114) compared to RA-THA. The remaining complication odds ratios, including those for infection, loosening, dehiscence, and "other" were similar between the groups.RA-THA is associated with lower risk of revision for dislocation within 1 year of index surgery, when compared to Manual-THA performed through the posterior approach.

To explore parents' and carers' perceptions of parenting a child with developmental dysplasia of the hip (DDH).A retrospective analysis of a questionnaire of parents and carers of children with hip dysplasia. Data analysis was guided by qualitative content analysis.There were 753 responses describing a range of parenting experiences. Three themes emerged: arduous parenting , detailed the parenting challenges, both practical and emotional posed by the management of DDH; insufficient understanding , described the social disconnection experienced by the respondents due to a lack of empathy from others; inconsistent guidance , encompassed respondents' reliance on health professionals for information and support, yet frustration at variability in the management of DDH.Overall, having to care for a child with DDH has a negative effect on the practice of parenting. Health professionals can support parenting and provide consistent education to assist parents' understanding of the complex nature of DDH management. What this study adds to the evidence: Despite a good prognosis, the diagnosis of hip dysplasia has a negative effect on of parenting. Parents and carers of children with hip dysplasia rely on the support of health professionals but find the associated loss of parenting autonomy distressing.

Proximal femoral screw hemiepiphysiodesis (PFSH) is a promising technique for treatment of hip subluxation in children with cerebral palsy (CP). The aim of this study is to report radiographic outcomes of PFSH and to evaluate its role in changing the natural history of hip displacement in children with CP.This is a single center retrospective chart review of children with CP that underwent PFSH with at least 2 years of radiographic follow-up. Demographic information, surgical details, complications, additional surgical procedures, and need for screw exchange were recorded. Radiographs were assessed for migration percentage (MP), neck shaft angle (NSA), head shaft angle (HSA), and articular trochanter distance preoperatively as well as at 6 months, 1 year, 2 year, and latest follow-up postoperatively. Hips were divided into group 1 (no previous hip surgery) and group 2 (PFSH performed after hip reconstruction). Hips with 2 years of preoperative radiographic data were included in the natural history cohort.Twenty-three patients (44 hips) met inclusion criteria with an average age of 7.3±1.7 years and a mean follow-up of 33.5 months. Group 1 and group 2 had 32 and 12 hips, respectively. Group 1 had significant improvement in all parameters (ΔMP=5%, ΔNSA=13 degrees, ΔHSA=15 degrees) group 2 showed improvements in NSA and HSA (ΔNSA=4 degrees ΔHSA=8 degrees) with only HSA reaching significance and MP remaining unchanged. All radiographic measurements worsened in the 2 years before surgery (N=25, natural history group) and improved after PFSH. Screw exchange occurred in 12 hips (27.2%) at an average of 33 months (range 27 to 42 mo) with 2 hips also undergoing pelvic osteotomy at that time. Three hips had a MP50% at follow-up with 2 hips in group 1 undergoing hip reconstruction. No complications were noted.PFSH effectively alters proximal femoral growth and can improve hip subluxation in children with CP. Screws often need to be exchanged and hips should be carefully monitored.Level III-retrospective comparative study.

Hip reconstruction is often necessary in children with cerebral palsy (CP) but is associated with high failure rates. Over-containment deeply seats the hip within the acetabulum at the time surgical reconstruction. The goal of this study is to evaluate the effect of over-containment on radiographic outcomes and failure rates in children with CP undergoing hip reconstruction.This study is a retrospective chart review of children with CP that underwent hip reconstruction between 2010 and 2019 with at least 2 years of radiographic follow-up. Migration percentage (MP), acetabular index (AI), and neck shaft angle (NSA) were recorded preoperatively, postoperatively and throughout follow-up. Failures were defined as a MP at latest follow-up ≥30% or need for revision hip reconstruction. Hips were divided into groups based on postoperative MP-group 1 (over-containment group) had a MP≤0% and group 2 had an MP0%. Radiographic parameters and failure rates were compared across Gross Motor Functional Classification Score (GMFCS) level, age at the time of surgery, and degree of preoperative subluxation.A cohort of 108 patients (197 hips) with an average age of 7.3±3.2 years met inclusion criteria with an average follow-up of 49.6 months (range: 24 to 118 mo). There were 147 hips in group 1 and 50 hips in group 2. At latest follow-up, group 1 demonstrated lower MP, AI, and NSA in comparison to group 2. The overall failure rate in our cohort was 8.1% (16 hips). Failure rates trended lowest in hips that were over-contained (6.1% v. 14.0%) although not statistically significant. Over-containment resulted in significantly lower failure rates in GMFCS IV/V hips, children under age 6 at the time of surgery and those with a higher degree of preoperative hip displacement (MP50%).Over-containment at the time of hip reconstruction can positively affect radiographic outcomes and failure rates in children with CP. Over-containment should be considered in hips at high risk of failure, especially non ambulatory children with significant hip subluxation at an early age.Level III-retrospective comparative study.

Human upright balance is maintained through feedback mechanisms that use a variety of sensory modalities. Vision senses information about the position and velocity of the visual surround motion to improve balance by reducing the sway evoked by external disturbances. This study characterized the effects of visual information on human anterior-posterior body sway in upright stance by presenting perturbations through a virtual reality system. This made it possible to use a new visual perturbation signal, based on trapezoidal velocity pulses, whose amplitude and velocity could be controlled separately. To date, the influences of visual field position and velocity have only been studied independently due to the experimental limitations. The hip displacement, ankle torques, shank angles, and surface EMGs of four major ankle muscles were measured bilaterally as outputs. We found that the root mean square (RMS) hip displacement (body angle) increased systematically with visual input amplitude. However, for each amplitude, the RMS body angle increased when input velocity was changed from 2 to 5 degrees per second (dps) and then decreased from 5 to 10 dps. Spectral analysis was used to compute frequency response over a frequency range from 0.04 to 0.6 Hz. The gain of body sway relative to the perturbation increased with frequency, whereas the coherence declined. Moreover, as the stimulus amplitude increased, the gain generally decreased, whereas the mean coherence values always increased. The mean gains and mean coherence values were greatest for the velocity of 5 dps. This study presents a novel experimental approach to study human postural control and augments our knowledge of how visual information is processed in the central nervous system to maintain balance.

Classic and reverse Bernese periacetabular osteotomy (PAO) have been shown to be effective for the treatment of developmental dysplasia of the hip (by classic PAO), severe acetabular retroversion (by reverse PAO), and some protrusio acetabuli (by reverse PAO). Especially in severe cases with higher degrees of correction, a relevant overlap between the osteotomized fragment and the pelvis might occur, leading to necessary fragment translation. The aim of the present study was to analyze the necessary translation as a function of the degree of correction using a statistical mean model of the pelvis according to the technique (classic PAO or reverse PAO).A mean statistical shape model of the pelvis and 2 extreme models were used to simulate rotation of the osteotomized fragment during a classic or reverse PAO and to calculate rotations from -20° to 20° in the frontal, sagittal, and transverse planes and a combination thereof. The depth and volume of the intersection between the mobilized fragment and the pelvis were calculated, and the minimum translation of the fragment necessary to avoid segment overlap was determined.The maximum intersection distances between the pelvis and the 20° rotated fragment were 6.7 and 15.3 mm for adduction and abduction (frontal plane), 6.4 and 4.5 mm for internal and external rotation (transverse plane), and 27.8 and 9.2 mm for extension and flexion (sagittal plane). The necessary translations for 20° of fragment rotation were 7.0 and 12.8 mm for adduction and abduction (frontal plane), 4.8 and 5.0 mm for internal and external rotation (transverse plane), and 18.5 mm and 8.8 mm for extension and flexion (sagittal plane).Acetabular reorientation with the classic or reverse PAO results in translation of the fragment and in a consequent change in the rotational center. This finding is more pronounced with higher degrees of fragment reorientation in abduction and extension; it becomes especially pronounced in reverse PAO for acetabular retroversion or protrusio acetabuli, and might limit the ability to achieve the intended improvement in overall hip biomechanics.

As no prior study has examined the citations profile of key articles related to periacetabular osteotomy (PAO), our analysis utilized the Web of Science database to (1) identify the most-cited clinical studies relating to PAO in the management of acetabular dysplasia and (2) assess any trends over time with respect to the quality of literature. The top 100 highest-cited studies related to PAO had a mean of 49 citations (range, 6-666 per study). With respect to the level of evidence, most studies had level IV evidence (58%); 1% level I, 16% level II, 28% level III and 2% level V. Most studies were retrospective ( n = 86); there were 14 prospective studies (including one randomized study). The most common study designs were case series ( n = 58) and cohort ( n = 16), followed by matched-cohort ( n = 13) and case-control ( n = 6). The mean ± SD Newcastle-Ottawa Scale score was 6.48 ± 1.31. A total of 59 and 41 of the included articles were classified as high risk and high quality, respectively. No studies were classified as very high risk. As a whole, our analysis demonstrated that currently available PAO literature is still of low quality and of low level of evidence. While PAO has been well-documented as a durable procedure for addressing acetabular dysplasia, future research must focus on higher quality, randomized and prospective data to answer key clinical or technique-related topics.

Postural management is a multi-disciplinary approach incorporating a comprehensive schedule of daily and night-time positions, equipment and physical activity to help maintain or improve body structures and function and increase activity and participation. Postural management may play a role in preventing contracture, deformity, pain, and asymmetry. This article provides an overview of the evidence supporting use of postural management to positively influence hip health in individuals with cerebral palsy, functioning as Gross Motor Classification System (GMFCS) levels IV or V. Sitting or lying without changing position for more than 8 hours, unsupported supine lying and asymmetrical or windswept postures are associated with pain and hip subluxation/dislocation. Although high-quality experimental research is still limited by many factors, there is limited evidence of harm, and most individuals at GMFCS IV or V require positioning supports to enable participation and function and ease caregiving. Clinical recommendations combining research and clinical opinion support the early use of comfortable positioning routines and/or equipment to reduce time spent in sustained asymmetrical or potentially harmful sitting and lying positions. Supported standing, active weightbearing and stepping are recommended to promote active movement and position change when possible, depending on individual, family and caregiver routines and preferences.

Hip dysplasia, subluxation, and eventual hip dislocation are commonly encountered in the cerebral palsy population secondary to spasticity and loss of motor control, especially in those patients with more severe neurologic involvement. The treatment of hip disorders in these patients should take into account the degree of limb and hip involvement, pain severity, and overall functioning. Conservative management focuses on mitigating spasticity and preserving range of motion in order to provide an environment in which the femoral head remains concentrically reduced in the acetabulum. However, operative management, consisting of soft tissue or tendon releases, femoral or pelvic osteotomies, or hip salvage procedures, is sometimes necessary to treat the painful, subluxated, or dislocated hip. Radiographic hip surveillance in the pediatric cerebral palsy population is used to guide operative treatment. Long term hip containment is generally improved when surgical intervention is performed in the earlier stages of dysplasia. Younger patients who demonstrate progressive hip subluxation despite conservative measures may be carefully selected to undergo soft tissue procedures. Bony reconstruction, with adjunctive soft tissue procedures, is often necessary to better contain the proximal femur in patients above the age of four years.

To compare pubo-femoral distance (PFD) in normal hips and those treated for developmental dysplasia of the hip (DDH) and to investigate the value of ultrasonography from the medial hip in early follow-up of dislocated DDH after reduction.This study included 58 infants (49 females) with DDH who presented with 65 dislocated hips (51 unilateral and 7 bilateral). Dislocation was treated by closed reduction for 53 and open reduction for 12 hips. Ultrasonography on the medial side of the hip was performed within 1-2 weeks and 4 weeks after reduction. The distance from the pubic bone to the femoral head (PFD) was measured to assess the reduction and stability of the femoral head and compared to that on the contralateral side (control) in cases of unilateral DDH.The PFD value for the normal group (2.9 ± 0.4 mm) was significantly less than that for the closed reduction group (4.9 ± 2.8 mm, P0.001) and that for the open reduction group (4.4 ± 1.6 mm; P=0.02), but no difference in the PFD was observed between the closed reduction and the open reduction groups (P=0.73). Despite successful reduction, the PFD values in the successful reduction group remained higher than those of the normal hips.PFD measurement by ultrasonography of the medial hip can be used to evaluate the effectiveness of reduction procedures in DDH. The clinical implications of post-reduction ultrasound evaluation in the diagnosis and long-term follow-up of outcomes require further research.