Binary Tönnis classification: simplified modification demonstrates better inter- and intra-observer reliability as well as agreement in surgical management of hip pathology.

BACKGROUND: The traditional Tönnis Classification System has inherent drawbacks as it is vulnerable to the subjectivity of a four-grade system. A two-grade classification could potentially be more reliable. The purpose of this study is to (1) compare the inter-observer and intra-observer reliability of the traditional Tönnis Classification System and a simplified Binary Tönnis Classification System for hip osteoarthritis and to (2) evaluate the clinical applicability of both systems. Our hypothesis is that the proposed Binary Tönnis Classification System will have better reliability and agreement for surgical decision-making. METHODS: Forty consecutive patients were selected to participate in this study. Patients were included in this study if they were between 35 and 60 years old. Patients were excluded if they had prior hip surgeries or conditions. All radiographs were randomized and blinded by a non-observer. Five fellowship-trained hip surgeons from a single center, in a fully crossed design, analyzed and graded all the radiographs utilizing the traditional Tönnis Classification System and the proposed Binary Tönnis Classification System. Intra- and inter-observer reliability values for both the systems were calculated using the Cohen's κ coefficient. A multi-rater κ was calculated using the weighted Fleiss method. RESULTS: The study sample contained 40 anterosuperior hip radiographs. For the traditional Tönnis Classification System, the weighted κ showed a fair inter-observer reliability (κ = 0.474) and excellent intra-observer reliability (κ mean = 0.866). For the proposed Binary Tönnis Classification System, both inter-observer and intra-observer reliability demonstrated excellent values, (κ = 0.858 and 0.928, respectively). On average, the Binary Tönnis Classification System correctly captured 87% of cases. When the traditional Tönnis Classification System was dichotomized, the capture rate was 84%. CONCLUSION: A simplified binary Tönnis Classification System demonstrates better reliability and clinical implementation than the traditional Tönnis Classification System.

[Short-term outcomes of total hip arthroplasty in the treatment of Tönnis grade 3 hip osteoarthritis in patients with spondyloepiphyseal dysplasia].

OBJECTIVE: Severe hip osteoarthritis, caused by bone or joint maldevelopment, biomechanical transformation and previous surgical intervention, is inclusively existed in spondyloepiphyseal dysplasia (SED). To investigate and discuss the short-term efficacy and possible effects of total hip arthroplasty in the treatment of Tönnis grade 3 hip osteoarthritis in patients with SED. METHODS: From January 2017 to June 2019, 374 patients with hip osteoarthritis were involved for total hip arthroplasty conducted by senior professional surgeons, of whom 9 patients (6 males and 3 females) with 12 hip osteoarthritis secondary to the SED met the inclusive and exclusive criteria and received the above-mentioned hip operation. The short-term outcomes were observed. RESULTS: All the patients were implanted with Johnson & Johnson ceramic on ceramic cementless hip prostheses within the arthroplasty. They were followed up for an average period of 20 months. Except for one muscular calf vein thrombosis case, no complications, such as aseptic loosening, joint dislocation, fracture, neurovascular injury, deep vein thrombosis and infection were observed in all the 9 patients. Before the surgery, the average Harris hip score was 35.55, while the average of the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) was 56.56. The level of quality of life indicated by SF-12 score was 41.56 on average. The mean pre-operation visual analogue scale (VAS) was 7.44. At the last follow-up, the average Harris hip score increased to 89.56, whereas the average WOMAC declined to 41.11. Compared with the baseline point, the average SF-12 score went up to 56.33. Dramatic drop of the mean VAS value to 2.67 was also observed at the last follow-up. In addition, post-operative increase of several pelvic-related parameters including pelvic incidence, pelvic tilt and sacral slope could be observed in the SED patients. The average measured pelvic incidence, pelvic tilt and sacral slope were 68.95°±4.60°, 52.75°±1.06° and 17.45°±1.77° before operation, respectively; whilst the mean value of these specific parameters increased to 76.98°±5.12°, 60.51°±4.35° and 18.10°±2.02°, respectively. The even leg lengths of the lower extremities were obtained after total hip arthroplasty. CONCLUSION: Total hip arthroplasty is satisfactory in the short-term pain relieve and function recovery for the management of Tönnis grade 3 hip osteoarthritis secondary to the SED.

Reliability of Tönnis classification in early hip arthritis: a useless reference for hip-preserving surgery.

INTRODUCTION: The Tönnis classification is widely accepted for grading hip arthritis, but its usefulness as a reference in hip-preserving surgery is yet to be demonstrated. We aimed to evaluate reproducibility of the Tönnis classification in early stages of hip osteoarthritis, and thus determine whether it is a reliable reference for hip-preserving surgery. MATERIALS AND METHODS: Three orthopaedic surgeons with different levels of experience examined 117 hip X-rays that were randomly mixed of two groups: a group of 31 candidates for hip-preserving surgery and a control group of 30 patients that were asymptomatic with respect to the hip joint. The surgeons were asked to rate an eventual osteoarthritis according to the Tönnis classification. After 2 months, the surgeons were asked to re-evaluate the X-rays in a random order. Intra- and interobserver reliabilities were calculated by comparing the observers' two estimations using Kappa statistics. RESULTS: Kappa values for interobserver reliability were slight or fair (range 0.173-0.397). Kappa values for intraobserver reproducibility were fair (range 0.364-0.397). Variance in grading no and slight osteoarthritis was the most frequent cause for intra- and interobserver disagreements (76.3 and 73.01% of the non-concordant observations, respectively). The confidence interval analysis showed that the observers' experience did not affect reproducibility. CONCLUSIONS: The Tönnis classification is a poor method to assess early stages of hip osteoarthritis. These findings suggest that its routine use in therapeutic decision-making for conservative hip surgery should be reconsidered.

[Risk factors for hip osteoarthritis after arthroscopy in patients with femoroacetabular impingement].

OBJECTIVE: To investigate the risk factors of hip osteoarthritis（HOA） after hip arthroscopy in patients with femoro-acetabular impingement（FAI） syndrome, and to reduce and prevent HOA. METHODS: From September 2018 to September 2020, 106 patients with FAI underwent hip arthroscopy, including 40 males and 66 females, aged from 20 to 55 years old with an average age of （33.05±10.19） years old. The mechanism of injury included 51 cases for sports injury, 36 for traffic accidents, and 19 for blunt object injury. The duration of the disease ranged from 5 to 19 days with an average of （12.02±3.69） days. All patients were followed up for 18 months. Patients were divided into HOA group （23 cases） and non-HOA group （83 cases） according to the occurrence of HOA. Multivariate Logistic regression was used to analyze the risk factors of HOA after hip arthroscopy in FAI patients. RESULTS: By univariate analysis, aged from 50 to 70 years old, female, body mass index（BMI）> 30 kg·m-2, physical labor, cam type, postoperative infection, last follow-up hip degree of motion （range of motion, ROM） （flexion, abduction, adduction, internal rotation） and Tönnis grade 1 and above of the HOA group were higher than those of the non-HOA group （P<0.05）, and the relative appendicular skeletal muscle index （RASM） was lower than that of non-HOA group（P<0.05）. By multiple Logistic regression analysis, cam type, BMI>30 kg·m-2, last follow-up hip internal rotation ROM and Tönnis grade 1 were risk factors for HOA after hip arthroscopy in FAI patients （P<0.05）. CONCLUSION: FAI classification, body mass index, hip ROM and Tönnis grade are all related to HOA after hip arthroscopy in FAI patients. Follow-up and intervention should be strengthened in high-risk FAI patients to reduce the occurrence of HOA.

Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted? / ¿Se puede predecir el pronóstico de la cadera contralateral tras una artroplastia total de cadera?

INTRODUCTION: Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty. MATERIAL AND METHODS: A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established. RESULTS AND CONCLUSIONS: A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

[Translated article] Prognosis of the contralateral hip after primary total hip replacement: Can it be predicted?

INTRODUCTION: Coxarthrosis is one of the most frequent and disabling pathologies. 20% of individuals over 60 years of age will develop symptomatic coxarthrosis and 10% of them will need a hip replacement; it is probably one of the orthopaedic procedures that most increases quality of life. When we recommend arthroplasty in clinical practice, patients often ask about the prognosis of their other hip. Will it deteriorate in the same way? Will it be necessary to replace it? When? The aim of the study is to determine if there is any variable or radiological sign that predicts the medium-term prognosis of the contralateral hip after total hip arthroplasty. MATERIAL AND METHODS: A retrospective review of patients who underwent total hip arthroplasty in our hospital during 2011 and 2012 was carried out, with a total of 543 patients. The coxarthrosis degree at X-ray was determined at the time of the first arthroplasty and at regular intervals during follow-up, according to the JOA and Tönnis classifications, analyzing each of the items included in these classifications. Its relation with the progression of osteoarthritis and the need of contralateral hip replacement was established. RESULTS AND CONCLUSIONS: A progression of osteoarthritis of the contralateral hip could be expected in the next 3 years in 10% of patients. This progression will be greater and faster in those with JOA grade III-IV/Tönnis grade II-III, especially, in those with greater joint narrowing and femoral head shape score, and can reach between 25 and 30% of patients. The initial JOA/Tönnis degree is a predictive factor for requiring a hip replacement on the contralateral side.

Practice Essentials of Imaging in Early Diagnosis of DDH.

INTRODUCTION: Developmental dysplasia of hip joint (DDH) is a dynamic progressive pathology which can tilt either way. The term strictly applies to primary dysplasia, where etiology is not clearly known. Secondary dysplasia can be due multiple causes, such as neuromuscular disorders, connective tissue disorders or skeletal syndromes. METHODS: The etiology being multifactorial, it needs a multidisciplinary team to address the issue at hand. The management starts antenatally with a detailed history of any risk factors and a dedicated ultrasound of the foetus, since forewarned is forearmed. At birth, a paediatrician having a keen sense of DDH will perform Barlow's or Ortolani's manoeuvre and can be the first one to sound the alarm in the event of positive findings. How and when a Radiologist needs to step in will depend on inter-departmental discussions between the paediatrician and the orthopedician. RESULTS: In the presence of positive clinical screening tests, and non-availability of ultrasound, a preliminary X ray pelvis AP view including both hip joints should be the requisitioned in a child of any age, particularly, if belonging to the high-risk group. If ultrasound is available, a screening exam till 6 months of age is recommended to rule out DDH. DISCUSSIONS: India is known for its vast numbers and little babies with occult diseases are the first to bear the brunt of conditions which have very few symptoms to start with. DDH is one such condition which most unfortunately expresses itself as a symptom only when it's too late, i.e., most often when the child begins to walk. Ultrasound is the modality of choice in neonates; however, since India is a country of modest means, in majority of the regions, radiographs still remain the first line of investigation.

Derotational Subtrochanteric Osteotomy and External Fixation for the Treatment of Neurogenic Hip Dislocation in Children with Cerebral Palsy: Could This Be a Viable Method of Treatment?

Purpose The treatment of painful and chronic dislocated hip in children with severe cerebral palsy (CP) is particularly demanding and controversial. Numerous surgical techniques have been described, and their outcomes vary a lot. The purpose of the present study is to evaluate a new method, which combines varus derotational subtrochanteric osteotomy (VDSO) and external osteosynthesis: (VDSOEO). Methods Six non-ambulatory children with spastic quadriplegia and chronic dislocated painful hips were treated. The technique involved a small incision on the subtrochanteric site of the osteotomy, followed by retention with a single-sided external osteosynthesis with rotational correction capability [swiveling clamp (SC)] for the reduction of the femur head in the acetabulum, and finally by the osteotomy. Hardware was removed without a second intervention four-six months postoperatively and after the osteotomy was healed. Evaluation of the method was based on clinical, functional, and radiological criteria. Results  Four patients achieved improved radiological scores. Two patients demonstrated resubluxation during the period of the osteotomy's healing process. However, no patients experienced pain, and all were able to sit post-surgery, while caregivers reported improved capacity for nursing care. Conclusions It is our strong belief that this approach can improve the quality of life in children with severe CP and painful and chronic dislocated hips. It is a viable and definitely less invasive procedure than classic pelvic or femur osteotomies.

Comparison of Interobserver Reliability between Junior and Senior Resident in Assessment of Developmental Dysplasia of The Hip Severity using Tonnis and International Hip Dysplasia Institute Radiological Classification.

Introduction: The radiographic classification for developmental dysplasia of hip to quantify the severity of disease consist of Tonnis and International Hip Dysplasia Institute (IHDI) classification. The Ossification center of the femoral head in DDH patient more than six months is still vague or eccentric, so the reliability of both classifications is still in question and especially is influenced by the experience of the observer. This study aims to test and compare interobserver reliability in evaluation of DDH patients using IHDI and Tonnis classification assessed by senior and junior orthopaedic residents which had different degree of experience. Materials and Methods: This study used retrospective analysis of pelvic supine AP view radiograph of DDH patients from 2014 to 2017. All three observer groups analysed the pelvis radiographs using Tonnis and IHDI classification. Inter and intra-observer reliability was measured by Cohen's and Fleiss Kappa method, respectively. Results: The Fleiss Kappa value for 15 radiographs of DDH patients assessed by senior residents using Tonnis and IHDI classification are 0.715 and 0.832 and result of Fleiss Kappa value assessed by junior residents are 0.577 and 0.845, respectively. Intra-observer reliability for Tonnis classification was lower in junior group compared to other two groups but showed almost perfect value in all groups for IHDI classification. Conclusion: Significantly different results were noted between junior and senior residents in assessing DDH severity, with higher diagnostic reliability in senior residents compared to junior residents. In general, junior resident has less clinical experiences in many aspects in comparison with the seniors.

Incidence of acetabular dysplasia in breech infants following initially normal ultrasound: the effect of variable diagnostic criteria.

PURPOSE: This study aimed to determine the incidence of acetabular dysplasia at six months of age in patients with breech presentation and previously normal hip ultrasounds, reporting primary radiographic measurements to allow for comparison with other patient cohorts. METHODS: A retrospective analysis of breech infants with initially normal clinical examinations and hip ultrasounds was performed to determine the rate of subsequent acetabular dysplasia and to characterise the distribution of acetabular index (AI). At approximately six months of age, AI was measured bilaterally on anteroposterior (AP) pelvic radiographs and reported using descriptive statistics. RESULTS: A total of 94 hips in 47 breech infants were eligible for analysis. All infants demonstrated normal ultrasound findings at a mean age of 6.9 ± 1.7 weeks and returned for follow-up at a mean age of 6.4 ± 0.5 months. On AP pelvic radiographs, mean right hip AI was 25.0°, with an interquartile range (IQR) (25th -75th percentile) of 23° to 27° and mean left hip AI was 25.5°, with an IQR of 22° to 28°. If one applies a single commonly used threshold value for defining dysplasia (AI ≥ 30°), 10/94 hips (10.6%) meet diagnostic criteria. Alternatively, strict adherence to previously established normative AI values stratified by gender and laterality results in 4/94 hips (4.3%) qualifying as significantly dysplastic. CONCLUSIONS: The proportion of breech infants who, despite normal initial ultrasound findings, were diagnosed with dysplasia at six months supports observation of breech-born patients beyond six weeks. Reliance on different threshold values for diagnosing acetabular dysplasia can lead to discrepancies in incidence rates.