Introduction and Objectives: The aim of this study is to analyze changes seen on X-ray of the acetabular index, Wiberg’s angle, Sharp’s angle and the continuity of Shenton’s line after osteotomy performed by means of the Dega technique in developmental dysplasia of the hip (DDH). Materials and Methods: We retrospectively analyzed 72 histories of children that underwent surgery performed using the Dega technique at the Niño Jesús Hospital over the last 15 years. We measured the rupture of the Shenton line, the acetabular index, Wiberg’s centre-edge angle and Sharp’s acetabular angle preoperatively; and then approximately 1 year after surgery and at the last X-ray control in the medical history. Results: The acetabular index changed from 33° preoperatively to 24° one year after surgery. At the last X-ray control the acetabular index was 23°. Wiberg’s centre-edge angle is normalized by osteotomy, and changed from 6° preoperatively to 20° after surgery. At the last X-ray it was 23°. However, Sharp’s acetabular angle only suffered slight modifications. It changed from 50° to 48° with surgery. Discussion and Conclusions: The Dega osteotomy is an effective technique to provide acetabular coverage in hips suffering from dysplasia before the closure of the triradiate cartilage. Both the acetabular index and Wiberg’s angle vary significantly with surgery, and become normalized in most cases. This correction is stable over time. However, the same cannot be said for Sharp’s acetabular angle which barely changes with osteotomy

Aims. Hip dysplasia (HD) leads to premature osteoarthritis. Timely detection and correction of HD has been shown to improve pain, functional status, and hip longevity. Several time-consuming radiological measurements are currently used to confirm HD. An artificial intelligence (AI) software named HIPPO automatically locates anatomical landmarks on anteroposterior pelvis radiographs and performs the needed measurements. The primary aim of this study was to assess the reliability of this tool as compared to multi-reader evaluation in clinically proven cases of adult HD. The secondary aims were to assess the time savings achieved and evaluate inter-reader assessment. Methods. A consecutive preoperative sample of 130 HD patients (256 hips) was used. This cohort included 82.3% females (n = 107) and 17.7% males (n = 23) with median patient age of 28.6 years (interquartile range (IQR) 22.5 to 37.2). Three trained readers’ measurements were compared to AI outputs of lateral centre-edge angle (LCEA), caput-collum-diaphyseal (CCD) angle, pelvic obliquity, Tönnis angle, Sharp’s angle, and femoral head coverage. Intraclass correlation coefficients (ICC) and Bland-Altman analyses were obtained. Results. Among 256 hips with AI outputs, all six hip AI measurements were successfully obtained. The AI-reader correlations were generally good (ICC 0.60 to 0.74) to excellent (ICC > 0.75). There was lower agreement for CCD angle measurement. Most widely used measurements for HD diagnosis (LCEA and Tönnis angle) demonstrated good to excellent inter-method reliability (ICC 0.71 to 0.86 and 0.82 to 0.90, respectively). The median reading time for the three readers and AI was 212 (IQR 197 to 230), 131 (IQR 126 to 147), 734 (IQR 690 to 786), and 41 (IQR 38 to 44) seconds, respectively. Conclusion. This study showed that AI-based software demonstrated reliable radiological assessment of patients with HD with significant interpretation-related time savings. Cite this article: Bone Jt Open 2022;3(11):877–884

Purpose: Femoroacetabular impingement (FAI) results from abnormal abutment between the proximal femur and acetabulum (Ganz et al., 2003). FAI occurs in three forms; cam, pincer and mixed (cam and pincer combined). The cam type has been quantified radiographically (Beall et al., 2005), but pincer FAI is poorly defined. Radiographic measures, including the center-edge angle (Wiberg, 1953), and Sharp’s angle (Sharp, 1961) have been used to define hip dysplasia, but these measures have not been used to define FAI. The purpose was to test these measurements to compare pincer patients with controls. Method: This study is a retrospective, observational analysis of anterior-posterior pelvic radiographs for control (N=76 hips; 40 patients) and pincer (N=20 hips; 19 patients) groups. Control radiographs were obtained from injury-free pelvic x-rays from the emergency department. Lateral center-edge (CE) angle Sharp’s angle and a proposed measurement of Femoral Head Containment (FHC) were measured using PACS. FHC was defined as the percentage of the 2D area of the femoral head circle covered by the acetabulum, using chord length, height and diameter of the femur head. Non-parametric statistics with post-hoc analyses were used. Pearson’s correlations were calculated for within- and between-observer reproducibility. Results: Mean (± SD) CE angle was significantly larger in the FAI group [37.4° (±5.2)] compared to controls [31.0° (±3.9)]. Mean Sharp’s angle was significantly less in the FAI group [37.6° (±3.9)] compared to the controls [41.2° (±3.5)]. Mean FHC was significantly larger in the FAI group [26.4% (±5.3)] compared to control group [21.5% (±5.3)]. Intra-observer r-values ranged from 0.86–0.97 and inter-observer correlations ranged from 0.93–0.96. There was significantly greater acetabular overcoverage in the pincer group based on these three measures, suggesting these may be used diagnostically. Conclusion: Pincer FAI is a debilitating condition that has not been quantified. This study found that CE angle, Sharp’s angle and FHC measures may be useful in diagnosing pincer FAI. A new method of quantifying FHC was proposed, evaluated and appears to be a promising new measure for evaluating pincer FAI. The CE and Sharp’s angles are simple, reproducible measures that can easily be used in a clinic setting to assist with diagnosing pincer FAI

The purpose of the study is to evaluate the retrospective results of 92 surgically treated spastic hips. Twenty-one patients were able to walk in the community with aids, 19 were able to walk about the house, and 13 were wheelchair bound. The mean age at the time of the operation was 7 yrs (3–18) and the average follow-up was 5. The cohort of the study included 45 tetraplegic patients, 6 diplegic, and 2 hemiplegic. The dislocated hips were 25 and the subluxated ones 67. The surgical treatment included soft tissue and bone procedures. The 53 patients were divided into two age groups: those less than 7yrs old and those older than 7yrs. The cohort was also divided into 39 patients operated in one setting, and 14 operated in more than one. Clinical evaluation was based on the joint range of motion, the ambulatory status and the pain. The radiological evaluation criteria were based on Reimer's migration index, the center-edge angle, Sharp's angle, and neck-femoral angle. We used the interclass correlation coefficient to measure our interobserver reliability for MI 0,93, for CE angle 0,95 and for Sharp's angle 0,81, as the interobserver difference for MI averaged 9% for CE angle 7and for Sharp's angle 3. Statistical analysis of continuous variables was done by Student's t-test or the Wilcoxon rank sum test. Categorical variables were evaluated by Fisher's test. Concerning the walking ability, from the 13 severe quadriplegic patients, none improved his functional level but they achieved better sitting balance. The walking ability of the rest of the patients improved one level in 78% of the cases. The mean preoperative abduction was improved from 24,7 to 33,5, the mean flexion was slightly reduced from 123 preoperatively to 114 postoperatively and the mean extension reduced from −20 preoperatively to −8 postoperatively. Reimer's index reduced from 67,2 to 21,7 postoperatively, the CE angle increased from −10,6 to 20,5, the Sharp's angle increased from 36,9 to 40,5 and the neck-shaft angle increased from 119,7 to 157,5post-operatively. Of greater significance were MI and CE at p<0.05. A migration index of >50% at final follow-up was associated with a worse migration index and a worse CE angle at 1 year post-operatively. 46 hips were evaluated as good, 30 as satisfactory, and 16 as poor. The severe tetraplegic with small-negative CE angle and Reimer's migration index > 50%, as well as the small age of the patients (<7 yrs) were negative prognostic factors. Better results were observed when patients were operated at age <7yrs by soft tissue procedures and MI<30%, while patients >7yrs had satisfactory results only after combined bony and soft tissue procedures and MI <50%. A migration index of >50% at final follow-up was associated with a worse migration index and a worse CE angle at 1 year postoperatively

To propose a modified approach to measuring femoro-epiphyseal acetabular roof (FEAR) index while still abiding by its definition and biomechanical basis, and to compare the reliabilities of the two methods. To propose a classification for medial sourcil edges. We retrospectively reviewed a consecutive series of patients treated with periacetabular osteotomy and/or hip arthroscopy. A modified FEAR index was defined. Lateral center-edge angle, Sharp's angle, Tonnis angle on all hips, as well as FEAR index with original and modified approaches were measured. Intra- and inter-observer reliability were calculated as intraclass correlation coefficients (ICC) for FEAR index with both approaches and other alignments. A classification was proposed to categorize medial sourcil edges. ICC for the two approaches across different sourcil groups were also calculated. After reviewing 411 patients, 49 were finally included. Thirty-two patients (40 hips) were identified as having borderline dysplasia defined by an LCEA of 18 to 25 degrees. Intra-observer ICC for the modified method were good to excellent for borderline hips; poor to excellent for DDH; moderate to excellent for normal hips. As for inter-observer reliability, modified approach outperformed original approach with moderate to good inter-observer reliability (DDH group, ICC=0.636; borderline dysplasia group, ICC=0.813; normal hip group, ICC=0.704). The medial sourcils were classified to 3 groups upon its morphology. Type II(39.0%) and III(43.9%) sourcils were the dominant patterns. The sourcil classification had substantial intra-observer agreement (observer 4, kappa=0.68; observer 1, kappa=0.799) and moderate inter-observer agreement (kappa=0.465). Modified approach to FEAR index possessed greater inter-observer reliability in all medial sourcil patterns. The modified FEAR index has better intra- and inter-observer reliability compared with the original approach. Type II and III sourcils accounts for the majority to which only the modified approach is applicable

Background. Rotational acetabular osteotomy (RAO) is an effective treatment option for symptomatic acetabular dysplasia. However, excessive lateral and anterior correction during the periacetabular osteotomy may lead to femoroacetabular impingement. We used preoperative planning software for total hip arthroplasty to perform femoroacetabular impingement simulations before and after rotational acetabular osteotomies. Methods. We evaluated 11 hips in 11 patients with available computed tomography taken before and after RAO. All cases were female and mean age at the time of surgery was 35.9 years. All cases were early stage osteoarthritis without obvious osteophytes or joint space narrowing. Radiographic analysis included the center-edge (CE) angle, Sharp's acetabular angle, the acetabular roof angle, the acetabular head index (AHI), cross-over sign, and posterior wall sign. Acetabular anteversion was measured at every 5 mm slice level in the femoral head using preoperative and postoperative computed tomography. Impingement simulations were performed using the preoperative planning software ZedHip (LEXI, Tokyo, Japan). In brief, we created a three-dimensional model. The range of motion which causes bone-to-bone impingement was evaluated in flexion (flex), abduction (abd), external rotation in flex 0°, and internal rotation in flex 90°. The lesions caused by impingement were evaluated. Results. In the radiographic measurements, the CE angle, Sharp's angle, acetabular roof angle, and AHI all indicated improved postoperative acetabular coverage. The cross-over sign was recognized pre- and postoperatively in each case. Acetabular retroversion appeared in one case before RAO and in three cases after RAO. Preoperatively, there was a tendency to reduce the acetabular anteverison angle in the hips from distal levels to proximal. In contrast, there was no postoperative difference in the acetabular anteversion angle at any level. In our simulation study, bone-to-bone impingement occurred in flex (preoperative/postoperative, 137°/114°), abd (73°/54°), external rotation in flex 0°(34°/43°), and internal rotation in flex 90°(70°/36°). Impingement occurred within internal rotation 45°in flexion 90°in two preoperative and eight postoperative cases. The impingement lesions were anterosuperior of the acetabulum in all cases. Discussion. It is easy to make and assess an impingement simulation using preoperative planning software, and our data suggest the simulation was helpful in a clinical setting, though there were some remaining problems such as approximation of the femoral head center and differences in femur movement between the simulation and reality. In the postoperative simulation there was a tendency to reduce the range of motion in flex, abd, and internal rotation in flex 90°. There was a correlation between acetabular anteversion angle and flex. Since impingement occurred within internal rotation 45°in flexion 90°in eight postoperative simulations, we consider there is a strong potential for an increase in femoroacetabular impingement after RAO

Purpose. This study aims to report the radiological corrections achieved and complication profile of Peri-Acetabular Osteotomy (PAO) undertaken through the minimally invasive approach. Method. 106 PAOs were performed in 103 patients, by senior author, using a minimally invasive approach from 2007 to 2015. Pre- and post-operative radiographs were reviewed and the degree of acetabular re-orientation was analysed. Case notes were examined retrospectively to identify haemoglobin levels and complications across two sites. Results. 73 female and 30 male patients underwent PAO procedures at a mean age of 25 years (9 – 54 years). Follow-up ranged from 23 to 80 months. 26 patients had concurrent proximal femoral osteotomies. Pre-operatively the average centre edge angle measured −1.6° with the vertical centre edge angle reading −0.2°. Post-operative radiographs confirmed correction of these values to 30° and 25.1° respectively. Sharp's angle also improved from a mean value of 49.5° to 33.3°. Review of the Tönnis angle showed correction from an average of 24.1° to 6.9°. The average drop in haemoglobin was calculated as 39 g/L with around 50 % of the patients requiring a peri-operative blood transfusion. The mean preoperative modified Harris Hip Score was 65.6 (Standard deviation σ=11.6) and the same at follow-up was 84.1(σ=11.5). Our outcome scores were comparable with recent PAO series including that of Gray et al. 10 patients reported lateral cutaneous nerve hypoesthesia and 9 had problematic screws. 2 patients underwent washouts as treatment for haematoma and infection. 4 patients had delayed union of the pubic osteotomy and a further 8 patients had asymptomatic osteotomy non-union. One posterior column non-union necessitated plating. One painful fibrous union of ischium and 3 inferior pubic rami stress fractures. Conclusion. This study shows that minimally invasive approach has favourable outcomes and that it is feasible to achieve adequate correction with results/complication profile comparable to traditional approach

In order to manage painful subluxation/dislocation secondary to cerebral palsy, 12 hips in 11 patients received combined femoral and Chiari pelvic osteotomies with additional soft tissues releases at an average age of 14.1 (9.1-17.8) years. Pain relief, improvement in the arc of movement, sitting posture and ease of perineal care was recorded in all, and these features have been maintained at an average follow-up of 13.1 (8-17.5) years. The improvement of general mobility was marginal, but those who were community walkers benefited the most. Pre-operative radiological measurements have been modified post-operatively to use lateral margin of the neo-acetabulum produced by the pelvic osteotomy. The radiological migration index improved from a mean of 80.6% to 13.7% [p<0.0001]. The mean changes in CE angle and Sharp's angle were 72° (range 56°- 87°) [p<0.0001] and 12.3° (range 9°- 15.6°) [p< 0.0001] respectively. Radiological evidence of progressive arthritic change was seen in only one hip, in which only a partial reduction had been achieved, and there was early joint space narrowing in another. Heterotopic ossification was observed in one patient with athetoid quadriplegia who remained pain free. In seven hips the lateral Kawamura approach, elevating the greater trochanter, provided exposure for both osteotomies and allowed the construction of a dome-shaped iliac osteotomy, while protecting the sciatic nerve. This combined procedure provides a stable hip with sustained pain relief for the adolescent and young adult presenting with pain

Dysplasia of the hip in children, characterised by a shallow acetabulum and a deficient coverage of the femoral head, generally causes altered biomechanics of the hip joint. A kinematic analysis on the individual and comparative spatial movement of the acetabulum with some of the pelvic osteotomy techniques is performed. The osteotomy providing greater correction in most of the parameters potentially leading to greater reduction in loading is the choice of the surgeon. Adult saw bone hip models have been used. Points of reference have been carefully chosen and data has been obtained using the Polhemus Electromagnetic measuring system before and after the osteotomy. Five techniques (Chiari, Salter, Steel, Tonnis and Ganz) have been performed, parameters like the Centre-edge angle, Sharp’s angle, Acetabular Head index (Femoral head cover), translation and rotation in 3 planes have been analysed. Results show an improvement in most of the parameters when the above pelvic osteotomies are performed. Centre-Edge angle improved by a mean (in degrees) of 7.4 (Chiari), 9.6(Salter), 16.9(steel), 28.4(Tonnis) and 31.0(Ganz). There has been marked increase in Femoral head cover with mean 24% with Tonnis and Ganz. Significant changes in rotational parameters in all 3 planes were achieved, particularly with Ganz and Tonnis techniques. Traditionally acetabular dysplasia correction has been assessed in one or two dimensions by plain radiographs and true three dimensional movement of the acetabulum is difficult to assess with simple techniques. This study describes a simple and reproducible method to compare the various pelvic osteotomies and comparative effects these can produce on the kinematics of the hip joint. It is intended to extend this study to include kinetics to compare the forces and stress distribution changes caused by performing the above techniques and a larger study is recommended, based on this technique and the initial trend of results shown

Objective: To review the existing classifications in characterizing the pathological morphology of congenital lower limb deficiencies and their usefulness in planning limb reconstruction. Methods: Ninety-five patients undergoing limb reconstruction were classified using existing classifications. Predominantly femoral deficiencies were classified using Aitken,Amstutz,Hamanishi,Gillespie andTorode,Fixsen and Lloyd-Roberts, Kalamchi, and Pappas systems and fibular deficiencies were classified using Coventry and Johnston, Achterman and Kalamchi, and Birch systems. Results: All patients with predominantly femoral deficiencies also had associated shortening of ipsilateral tibia and fibula. Similarly, most patients with predominantly fibular deficiencies also had some associated shortening ipsilateral femur. Acetabular dysplasia, knee instability due to cruciate insufficiency and lateral femoral condylar hypoplasia were found in both femoral and fibular deficiencies. None of the existing classification systems were able to represent the complete pathologic morphology in any given patient. Due consideration of alignment, joint stability and length discrepancy of affected limb as a whole at the planning stage of reconstruction could not be ascertained using these classification systems. Instead, it was useful to characterize the morphology of the involved limb using the following method:. Acetabulum: Dysplastic/ Non-dysplastic (AC index, Sharp’s angle, CE angle). Ball (Head of femur): Present/Absent. Cervix (Neck of femur): Presence of pseudoarthrosis & neck-shaft angle. Diaphysis of femur: Length / deformity. Knee: Presence of cruciates, patellar and femoral con-dylar hypoplasia. Fibula and Tibia: Presence/ absence, length and deformity. Ankle: Normal/Ball and socket/ valgus. Heel: Presence of tarsal coalition and deformity (valgus, equinus). Ray: Number of rays present in the foot. Conclusion: Congenital longitudinal lower limb deficiency is a spectrum of disorder involving the entire lower limb. Existing classifications do not represent the complete morphology of the entire involved lower limb and therefore a systematic method of characterizing the morphology of the lower limb is more useful in planning limb reconstruction

We evaluated long-term follow-up clinically and radiologically of patients with developmental dysplasia of the hip operated between 1956 and 1971 with adductor tenotomy and open reduction of the hip. Ninety-six patients with developmental dysplasia of the hip were operated between 1956 and 1971. Their ages were from 10 months to 44 months. Eighty-eight patients (88.5%) were girls and 11(11.5%) were boys. There were 58 unilateral cases and 38 bilateral cases for a total of 134 operated hips. The cases with bilateral involvement were operated simultaneously. For all patients, the surgical team used the same technique consisting of open reduction through a Smith Petersen incision together with an adductor tenotomy and lengthening or tenotomy of the Psoas muscle. Postoperative immobilization was a pelvic-toe cast for one month followed by two plaster casts with abduction rod for three to five months. Postoperative follow-up was from 15 years to 44 years, 4 months (mean: 24 years, 4 months). The clinical outcome evaluated pain, range of motion, limp, muscle strength, and leg length discrepancy. Radiological evaluation included Mose index, acetabular head index, Wiberg’s CE angle, medial articular space, Sharp’s angle, acetabular index of the weight-bearing zone, acetabular depth, radial quotient in unilateral cases, width and shape of teardrop, collodiaphyseal angle, Shenton line, and degenerative changes of the hip. The results of clinical evaluation were: Excellent – 60 (44.7%), Good – 35 (26.1%), Fair – 26 (19.4%), Poor – 13 (9.7%). Radiological results according to a modified Severin classification were: Class I – 60 (44.7%), Class II – 33 (24.6%), Class III – 31 (23.1%), Class IV – 9 (6.7%), Class V – 1 (0.7%), Class VI – 0 (0%). Complications were: infections in six hips (4.4%), three (2.2%) being deep ones. Avascular necrosis according to Bucholz and Odgen occurred in 38 hips (28.3%). Four hips (3%) were Type I, 31 hips (23.1%) were Type II, three hips (2.2%) were Type III. Degenerative changes occurred in 29 hips (21.6%) of which seven hips (5.22%) were Grade I, 12 hips (8.95%) were Grade II, and 10 hips (7.46%) were Grade III. Our conclusions were: 1.) Open reduction of developmental dysplasia of the hip is a valid method in late treatment or failure of orthopaedic treatment. 2.) Clinical results are better than radiological results. 3.) The rate of degeneratives changes increases with long-term follow-up. 4.) The best radiological results are achieved in patients who are younger than one and half year of age at the time of surgery. 5.) There was a significant rate (23.1%) of avascular necrosis Type II according to the Bucholz and Odgen classification, but this can only be realized with long-term follow-up

Postdysplastic ischaemic necrosis of the proximal femoral epiphysis has its origin in the vascular crisis during conservative or operative treatment of DDH and in the majority of cases has an iatrogenic origin. The severity of the symptoms and functional disability is dependent on the anatomic changes of the proximal femur and the whole hip joint respectively, which were caused by previous conservative or operative treatment, including repeated surgery. The symptoms such as limping from leg length discrepancy and abductor insufficiency, pain and restricted ROM are less apparent in small children, but become more conspicuous with the approach of the end of growth. For the classification of the patterns of ischemic necrosis of the femoral head, the classification according to Bucholz and Ogden was used. Four principal types of this deformity are recognised. There are three main problems which are to be solved by surgical treatment. 1. The acetabular dysplasia with a pelvic osteotomy 2. Improving the bio-mechanics by distalisation of the greater trochanter and by the lengthening of the femoral neck with or without valgisation 3. Lengthening of the shorter extremity. The decision on the type of surgery to be performed depends on the age of the patient and the severity of the anatomic deformity, as well as the functional disability. A very useful method for treatment was found to be a double intertrochanteric osteotomy with a trochanteric advancement, and almost invariably in combination with a triple or Salter pelvic osteotomy. The lengthening osteotomy of the femoral neck follows the principles of Müller and Wagner. A similar technique was also proposed later by Morscher. My own contribution has been to modify the operation by an oblique execution of the osteotomy, and a method of fixation of the greater trochanter by means of an angle plate – providing a lengthening of the limb by up to 3 cm. In the case of acetabular dysplasia, a pelvic osteotomy should be performed as a first procedure in order to obtain better stability of the hip joint. A femoral osteotomy can follow at a minimal interval of three months. If the femoral osteotomy is performed as a first step without enlargement of the actabulum, there is the risk of further deterioration of the covering of the femoral head, even in a dislocation. This philosophy of treatment of sequel of postdysplastic necrosis has been used since 1979. Up to 1984, we operated on 48 hip joints in 46 patients, 39 girls and 7 boys aged 4 to 21, with a follow- up of at least 15 years. In 12 cases, 10 girls and 2 boys aged 4 to 8, a Salter and valgus osteotomy was performed. Thirty-four patients (29 girls and 5 boys) had a triple pelvic osteotomy, with 2 girls being operated bilaterally. In 22 hips, a lengthening osteotomy of the femoral neck was added as a second stage procedure. Five parameters were used for clinical evaluation: pain, limping, range of motion, Trendelenburg sign, and leg length discrepancy. For radiological assessment, we used an AP X-ray of the entire pelvis taken before and after osteotomy, and also during follow-up. CE angle, Sharp’s angle, ACM angle, and lateralisation were recorded. Hip score was measured on all hips, but we found that CE, Sharp and lateralisation were of greater value. In a group of 12 cases operated on up to the age of 8 by combining Salter and valgus osteotomy, a cementless THR was necessary for a young woman of 25. The remaining 11 patients are up to the present time without any major problems. In a group of 14 patients operated for sequel of postdysplastic necrosis Type II deformity (all with triple pelvic osteotomies and five in combination with femoral neck lengthening osteotomy), all have a normal quality of life, including having natural childbirths. From 22 Type III hip joints in 20 patients operated for sequel of postdysplastic necrosis, a cementless THR was implanted in three cases 14, 17 and 18 years after original surgery. Fourteen patients (15 hip joints − 67%) can be considered as good results without needing to have any therapy. Three patients (4 hips) suffer from degenerative arthritis and are candidates for THR

Aims

Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes.

Aims

The aim of this study was to investigate whether anterior pelvic plane-pelvic tilt (APP-PT) is associated with distinct hip pathomorphologies. We asked: is there a difference in APP-PT between young symptomatic patients being evaluated for joint preservation surgery and an asymptomatic control group? Does APP-PT vary among distinct acetabular and femoral pathomorphologies? And does APP-PT differ in symptomatic hips based on demographic factors?