Reliability and validity of the Hartofilakidis classification system of congenital hip disease in adults

The neoacetabulum in developmental dysplasia of the hip is covered with hyaline cartilage

The lack of adequate mechanical stimulation and appropriate contact between acetabulum and femoral head results with developmental dysplasia of the hip (DDH). In DDH, hip joint forms normally during the organogenesis, but deforms during the fetal development. Acetabulum remains comparable in width with normal acetabulum, but has increased length and decreased depth, resulting in a poor coverage of the femoral head. In cases of severe hip subluxation and luxation due to DDH, the femoral head articulates with the external side of the iliac bone, forming a neoacetabulum in the position that was genetically predetermined to become bony tissue. A neoacetabulum is therefore formed under intermittent mechanical pressure, but never has the depth of a physiological acetabulum due to different forces at this new location. Over time, the depth of the neoacetabulum increases, and a crest is formed that obstructs reposition of the femoral head into the anatomic acetabulum. We hypothesize that the neoacetabulum on the iliac bone in DDH patients is formed of hyaline cartilage, despite the lack of genetic predisposition for hyaline cartilage formation in this area. We assume that as the femoral head migrates during development in such patients, joint capsular tissue interposes between the external side of the iliac bone and the femoral head, and a cartilaginous metaplasia of the capsule follows. This results in elongation of the acetabular cartilage in the same direction as the femoral head migrated. This assumption is based on the finding that in patients with hip luxation such interposed joint capsule showed signs of cartilaginous transformation. Furthermore, in the inner part of such joint capsules, proteoglycan production was notably higher than that of other non-cartilaginous tissue. Also, high expression of cartilaginous genes, which are usually not expressed in this tissue, was observed. Confirmation of this hypothesis would put a new perspective on the pathogenesis of DDH and could lead to better management or even prevention of this condition.

Patella alignment abnormality in patients with developmental dysplasia of the hip

BACKGROUND

The purpose of this study was to assess the influence of developmental dysplasia of the hip (DDH) on patella alignment.

METHODS

The radiographic data of all the patients who met the inclusion criteria from January 2015 to July 2017 were reviewed, including the quadriceps angle (QA), patellar lateral tilt (PTA), sulcus angle (SA), lateral shift of patella (LSP), and lower limbs alignment. The patients were divided into three groups in accordance with lateral center-edge angle (LCE) and femoral neck torsion angle (FNTA): group A (LCE > 25° and FNTA < 40°), group B (LCE < 20° and FNTA < 40°), and group C (LCE < 20° and FNTA > 40°).

RESULTS

One hundred thirty-eight patients with 230 hips (115 females and 23 males) were recruited with an average age of 22 years. There were significant differences between group A and group C as well as group B and group C in QA, SA, PTA, LSP, and lower limbs alignment (p < 0.01). There were no differences in SA, PTA, LSP, and lower limbs alignment (p >0.05) and significant differences in QA (p < 0.01) between group B and group C. The "Pearson's" correlation analysis of the data in total of group B and group C showed that FNTA and LCE and QA and LCE were negatively correlated, whereas FNTA and QA, PTA, SA, and lower limbs alignment as well as SA, PTA, and lower limbs alignment were positively correlated.

CONCLUSION

Patients with DDH not only have hip joint change, but also have the patella alignment abnormality, which may lead to patella instability. In the clinic, we should pay attention to the hip development of the patella instability patients for excluding DDH. Level of Evidence: Prognostic level III.

Application of three-dimensional reconstruction to improve the preoperative measurement accuracy and applicability of femoral neck torsion angle

Conventional methods have limitations in measuring femoral neck torsion angle (FNTA) of patients with femoral deformities. A new method of three-dimensional (3D) reconstruction technology based on computer tomography (CT) was proposed to enhance measurement accuracy and applicability in this study.Bilateral FNTA of 50 developmental dysplasia of the hip (DDH) patients (DDH group) and 81 volunteers (normal group) were measured by Mimics software based on CT data with the marker lines determined by centerline and curvature. Each FNTA was measured by observer A and observer B for twice separately. 50 DDH patients were classified into 3 groups (group I, II, III) according to Hartofilakidis classification. The statistical analysis of the differences was made among the measurements of the FNTA.The FNTA values were 27.56° ± 12.48° in DDH group and 21.22° ± 8.14° in normal group with significant difference (t = 4.516, P < .001). The FNTA values were 24.53° ± 2.40° in group I, 29.78° ± 1.83° in group II and 39.08° ± 3.13° in group III, with significant difference (F = 7.568, P = .001).The accuracy, reliability and applicable scope of FNTA measurement can be improved by 3D reconstruction in clinical practice. The applicable scope of this method included normal people and patients with femoral deformities. The FNTA of DDH patients is significantly larger than normal volunteers with a positive correlation between the severity of classification. This study will also provide references for preoperative design of Chinese population.

Lessons learned from study of congenital hip disease in adults

Orthopaedic surgeons specialising in adult hip reconstruction surgery often face the problem of osteoarthritis secondary to congenital hip disease (CHD). To achieve better communication among physicians, better treatment planning and evaluation of the results of various treatment options, an agreed terminology is needed to describe the entire pathology. Furthermore, a generally accepted classification of the deformities is necessary. Herein, the authors propose the use of the term “congenital hip disease” and its classification as dysplasia, low dislocation and high dislocation. Knowledge of the CHD natural history facilitates comprehension of the potential development and progression of the disease, which differs among the aforementioned types. This can lead to better understanding of the anatomical abnormalities found in the different CHD types and thus facilitate preoperative planning and choice of the most appropriate management for adult patients. The basic principles for improved results of total hip replacement in patients with CHD, especially those with low and high dislocation, are: Wide exposure, restoration of the normal centre of rotation and the use of special techniques and implants for the reconstruction of the acetabulum and femur. Application of these principles during total hip replacement in young female patients born with severe deformities of the hip joint has led to radical improvement of their quality of life.

Influence of experience on intra- and inter-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classifications

INTRODUCTION

A previous study demonstrated that the reproducibility of the Crowe (Cr), the Hartofilakidis (Ha) and the modified Cochin (Co) classifications were comparable. However, there were differences with a trend that suggested the influence of experience. Therefore, we performed a prospective study to investigate whether experience influenced the reproducibility of the commonly used developmental dysplasia of the hip (DDH) classifications.

HYPOTHESIS

The hypothesis was that the intra- and inter-observer reproducibility scores would be higher in the senior group than the junior group, and particularly for the modified Co classification.

METHODS

Four seniors and four residents classified 104 A/P pelvic radiographs (200 hips) two times using the Cr, Ha and Co classification systems.

RESULTS

For intra-observer reproducibility, the average weighted concordance coefficients [95% confidence intervals] were for the senior and the junior groups: 92.2 [88.6-95.7] and 92.6 [87.9-97.2] for Cr, 92.1 [88.7-94.6] and 92.0 [87.7-96.3] for Ha, 94.2 [91.8-96.6] and 94.1 [91.5-96.6] for Co. The average weighted Kappa (95% confidence intervals) were 0.8 [0.71-0.88] and 0.79 [0.68-0.89] for Cr, 0.77 [0.74-0.81] and 0.75 [0.62-0.88] for Ha, 0.82 [0.76-0.89] and 0.80 [0.74-0.87] for Co. The junior inter-observer reproducibility multi-rater Kappa (list A:list B) were 0.57:0.50 (Cr), 0.47:0.53 (Ha), 0.42:0.42 (Co). Senior multi-rater Kappa were 0.53:0.49 (Cr), 0.40:0.34 (Ha), 0.40:0.43 (Co).

CONCLUSIONS

Contrary to our hypothesis, the experience of the observer did not affect the intra- and inter-observer reproducibility of the three classification systems.

Small diameter acetabulum and femoral head in total hip arthroplasty for developmental dysplasia of the hip, with no femoral osteotomy

We present the results of 66 total hip arthroplasties in 62 patients of mean age 46 years (24-74 years), with developmental dysplasia of the hip. In all cases the centre of rotation of the new hip was positioned at the site of the true acetabulum. In all patients cementless press fit acetabular components of small diameter (42-44 mm) were used, articulating exclusively with a 22.25 mm modular metal femoral head, without the use of bone grafts or shortening osteotomies of the femur. Despite the use of small diameter femoral heads the rate of dislocation was 3%. After an average follow-up period of 9 years (4-18 years), no revisions were required for infection, loosening or wear or implant migration. Osteolytic lesions were seen in the periacetabular region in 3 patients who were symptom free. A total of 2 revisions were required for instability and 2 patients had the wires of their trochanteric osteotomy removed because of bursitis. Leg length inequality was improved in 55% of the patients and one postoperative transient sciatic nerve lesion settled within 4 months. We believe that in patients with painful dysplastic hips, the use of small diameter implants with the centre of rotation at the true acetabulum, can give very satisfactory results, without any supplementary procedures.

Can Radiographs Predict the Use of Modular Stems in Developmental Dysplasia of the Hip?

BACKGROUND

Abnormal anatomy frequently results in the use of a modular stem in patients undergoing primary total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH). However, because these stems are not always available in the operating room, it would be helpful if standard radiographic views could be analyzed in such a way that patients whose femoral anatomy might call for stem modularity could be anticipated before surgery. To our knowledge, no such parameters have been defined.

QUESTIONS/PURPOSES

In the senior author's practice, we used femoral neck anteversion of more than 25° as a determinant for use of a modular stem. Given this criterion, we asked if we could reliably identify plain film radiographic parameters of the femur that predict the use of modular stems. We looked at the following: (1) the neck-shaft angle based on the anteroposterior (AP) radiograph (alpha); (2) the neck-shaft angle from the crosstable lateral radiograph (beta); and (3) the calculated femoral anteversion angle.

METHODS

We reviewed preoperative radiographs from 50 of 67 patients (79 hips) who had a primary diagnosis of DDH and underwent primary THA from January 1999 to February 2007 inclusive. Hips with prior femoral-sided surgery (n = 2) or without preoperative films (n = 19) were excluded. Furthermore, patients with bilateral hips had the second hip excluded (n = 8). Twenty-one of 50 received a modular femoral stem based on the criterion of intraoperative neck-shaft anteversion of greater than 25° as measured by the senior surgeon (CLP), whereas the remainder received tapered nonmodular stems. There were no differences in age, sex, height, or weight between the modular stem group and tapered stem group. Radiographs were evaluated to record the parameters listed.

RESULTS

Patients in whom modular femoral stems were used had a greater mean AP (alpha) neck-shaft angle compared with patients who received tapered nonmodular stem (152°; 95% confidence interval [CI], 146°-157° versus 137°; 95% CI, 134°-141°; p < 0.001) with an optimal cutoff point for determining the use of modular stems of ≥ 142° (receiver operating characteristic [ROC] area = 73%). Hips in which modular femoral stems were chosen had a smaller mean lateral (beta) neck-shaft angle (152°; 95% CI, 148°-157° versus 161°; 95% CI, 158°-164°; p = 0.003) with an optimal cutoff point of ≤ 153° (ROC area = 65%). Hips in which modular femoral stems were used had a higher femoral anteversion angle (mean 45°; 95% CI, 37°-54° versus 21°; interquartile range, 17°-25°; p < 0.001) with an optimal cutoff of ≥ 32° (ROC area = 80%).

CONCLUSIONS

Preoperative radiographs anticipated the use of modular stems during THA for DDH in a practice where modular stems were chosen on the basis of a neck-shaft angle of greater than 25° measured at surgery. We found that this could be predicted on preoperative radiographs based on smaller lateral neck-shaft angles, steeper AP radiographic neck-shaft angles, and increased femoral anteversion calculated using these angles. Prospective studies are needed to better determine if these cutoff values adequately predict the use of modular stems.

Comparison of the inter- and intra-observer reproducibility of the Crowe, Hartofilakidis and modified Cochin classification systems for the diagnosis of developmental dysplasia of the hip

INTRODUCTION

Developmental dysplasia of the hip (DDH) leads to multiple treatment challenges during adulthood. Surgical treatment is mainly based on radiographic evaluation of the anatomical alterations. Several classification systems have been described in the published English scientific literature, but the French Cochin classification has not been used very much. Its primary advantage lies in its ability to intricately describe the DDH alterations with a large number of grades. We hypothesized that the inter- and intra-observer reproducibility of the SOFCOT-modified Cochin classification system was equal to that of the Crowe and Hartofilakidis classifications.

MATERIAL AND METHODS

Five French orthopaedic surgeons who were DDH experts classified 94 A/P pelvis radiographs (179 hips) using the Crowe (Cr), Hartofilikadis (Ha) and modified Cochin (Co) systems. This evaluation was repeated a second time one month later. The intra-observer reproducibility was determined with weighted Kappa and concordance coefficients. The inter-observer reproducibility was performed by calculating the multirater Kappa coefficient on each of the two data series.

RESULTS

For the intra-observer reliability, the average weighed concordance coefficients (95% CI) were 88.62-94.52 for Cr, 89.43-93.80 for Ha and 92.14-95.71 for Co. The average weighed Kappa coefficients (95% CI) were 0.70-0.85 for Cr, 0.67-0.82 for Ha and 0.75-0.83 for Co. For the inter-observer reliability, the Kappa for each assessment round was 0.57 and 0.48 for Cr, 0.43 and 0.44 for Ha, and 0.43 and 0.37 for Co.

DISCUSSION

The intra- and inter-observer reliability for the modified Cochin classification system is the same as the one for the Crowe and Hartofilakidis classifications. The theoretical advantage of this classification system should be confirmed by comparing the findings with intra-operative anatomical observations.

LEVEL OF PROOF, TYPE OF STUDY

IV.

Reconstruction of the Acetabulum in Developmental Dysplasia of the Hip in total hip replacement

Developmental dysplasia of the hip (DDH) or congenital hip dysplasia (CDH) is the most prevalent developmental childhood hip disorder. It includes a wide spectrum of hip abnormalities ranging from dysplasia to subluxation and complete dislocation of the hip joint. The natural history of neglected DDH in adults is highly variable. The mean age of onset of symptoms is 34.5 years for dysplastic DDH, 32.5 years for low dislocation, 31.2 years for high dislocation with a false acetabulum, and 46.4 years for high dislocation without a false acetabulum. Thorough understanding of the bony and soft tissue deformities induced by dysplasia is crucial for the success of total hip arthroplasty. It is important to evaluate the existing acetabular deformity three-dimensionally, and customize the correction in accordance with the quantity and location of ace tabular deficiencies. Acetabular reconstruction in patients with DDH is challenging. Interpretation of published data is difficult and should be done with caution because most series include patients with different types of hip disease. In general, the complication rate associated with THA is higher in patients with hip dysplasia than it is in patients with osteoarthritis. Overall, clinical and functional outcomes following THA in patients hip dysplasia (DDH) differ from those treated for primary hip osteoarthritis, possibly due to the lower age and level of activity. Although function scores decline with age, the scores for pain and range of motion presented with a statistically significant improvement in the long-term.

Morphological analysis of the knee joint in patients with hip dysplasia

PURPOSE

The purpose of this study was to investigate the morphological changes of the knee in patients with untreated developmental dysplasia of the hip.

METHODS

Morphological analysis of 150 knee joints in 75 patients with developmental dysplasia of the hip was performed by examining computed tomographic (CT) images. Of these patients, 36 had unilateral developmental dysplasia of the hip and 39 had bilateral developmental dysplasia of the hip. Therefore, 36 hips were normal, and 114 hips were dislocated. CT images ranged from the iliac crest to 2 cm inferior to the tibial tuberosity.

RESULTS

Compared with the knees in patients with normal hips, the femoral condyles in patients with dislocated hips were smaller and exhibited greater medial and lateral condylar asymmetry. The anterior femoral condylar angle of the femur was increased, as was the groove angle, while the trochlear groove was shallower in patients with dislocated hips. Furthermore, the lateral patella shift was reduced and the patellar tilt angle was increased in patients with dislocated hips compared with patients with normal hips. The extent of changes in these variables differed with the degree of dislocation. However, the posterior condylar angle of the femur was not affected by the degree of dislocation.

CONCLUSION

These findings suggest that developmental dysplasia of the hip is associated with morphological changes in the knee joint. These changes should be considered during hip and knee surgery.

LEVEL OF EVIDENCE

Prospective study, level II.

Total hip arthroplasty in young females with congenital dislocation of the hip, radically improves their long-term quality of life

Eighty-two female patients with low dislocation (67 hips) or high dislocation (48 hips) were assessed using clinical scores and EQ-5D quality of life (QoL) questionnaire. Assessment was performed at the first to secondyear postoperatively and at the final follow-up, after a minimum of 12 years (12-37). Patients reported with a high EQ-5D health state VAS scale, VAS index and TTO index at 1 to 2 years follow-up (94,21/0,907/0,931) that remained considerably high despite the long-term follow-up (73,8/0,721/0,746). The scores for pain and range of motion presented with a statistically significant improvement at 1 to 2 years postoperatively and at the time of final follow-up. Function scores have declined with age. Total hip arthroplasty in CHD patients radically improves QoL for a long period of time.

Inter- and intraobserver reliability of the Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients

BACKGROUND

The purpose of this study is to investigate the inter- and intraobserver reliability of Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients.

MATERIALS AND METHODS

Two consultant orthopedic surgeons classified 141 dysplastic hips on 103 standard anterior-posterior pelvis radiographs according to the Crowe and Hartofilakidis classifications. Assessments were performed in random order by each observer on two separate occasions, at least 4 weeks apart. Kappa statistics were used to establish a relative level of agreement between observers for the two readings and between separate readings by the same observer.

RESULTS

At the first readings, interobserver reliability analysis revealed kappa coefficient of 0.71 for the Crowe classification and 0.54 for the Hartofilakidis classification. At the second reading, the kappa coefficient was 0.72 for the Crowe classification and 0.75 for the Hartofilakidis classification. Intraobserver reliability analysis revealed kappa coefficients of 0.71 for the Crowe and 0.80 for the Hartofilakidis classification for observer A, and 0.76 and 0.70 for observer B.

CONCLUSIONS

In conclusion, we have found substantial inter- and intraobserver agreement for Crowe classification and substantial to moderate agreement for Hartofilakidis classification in this study. Both classification systems assess the different aspects of developmental dysplasia of hip in adults. Each system has advantages and disadvantages. We suggest using both of these classifications together to increase the accuracy.

Total hip arthroplasty for adult hip dysplasia

Preoperative planning is essential to define anatomy, clarify the operative approach and exposure, and ensure that suitable implants are available.Concerns exist regarding the long-term effectiveness and safety of hip resurfacing arthroplasty for the young dysplastic hip.In light of current evidence, concerns exist regarding the use of metal-on-metal articulations for hip arthroplasty in the young dysplastic hip.The ideal bearing surface is not known, although the longest data available support the use of metal-on-polyethylene.

Congenital hip disease in adults: terminology, classification, pre-operative planning and management

This paper reviews the current knowledge relating to the management of adult patients with congenital hip disease. Orthopaedic surgeons who treat these patients with a total hip replacement should be familiar with the arguments concerning its terminology, be able to recognise the different anatomical abnormalities and to undertake thorough pre-operative planning in order to replace the hip using an appropriate surgical technique and the correct implants and be able to anticipate the clinical outcome and the complications.