Abstract. Purpose The aim of this study was investigate the relationship between version and torsional abnormalities of the acetabulum, femur and tibia in patients with symptomatic FAI. Methods A systematic review was performed according to PRISMA guidelines using the EMBASE, MEDLINE, PubMed and Cochrane databases. Original research articles evaluating the described version and torsional parameters in FAI were included. The MINORS criteria was used to appraise study quality and risk of bias. Mean version and torsion values were displayed using forest plot and the estimated proportion of hips displaying abnormalities in version/torsion were calculated. Results. A total of 1206 articles were identified from the initial search, with 43 articles, involving 8,861 hips, meeting the inclusion criteria. All studies evaluating femoral or acetabular version in FAI reported ‘normal’ mean version values (10. 0. to 25. 0. ). However, distribution analysis revealed that an estimated 31% and 51% of patients with FAI displayed abnormal central acetabular and femoral version respectively. Conclusion. Up to 51% of patients presenting with symptomatic FAI show an abnormal femoral version, whilst up to 31% demonstrate abnormal acetabular version. This high percentage of version abnormalities highlights the importance of evaluating these parameters routinely during assessment of patients with FAI, in order to guide clinical decision making

Introduction. The deformity in osteoarthritis (OA) of the knee has been evaluated mainly in the frontal plane two dimensional X-ray using femorotibial angle. Although the presence of underlying rotational deformity in the varus knee and coexisting hip abnormality in the valgus knee have been suggested, three dimensional (3D) deformities in the varus and valgus knee were still unknown. We evaluated the 3D deformities of the varus and valgus knee using 3D bone models. Methods. Preoperative computed tomography (CT) scans of twenty seven OA knees (fifteen varus and twelve valgus) undergoing total knee arthroplasty were assessed in this study. CT scans of each patient's femur and tibia, with a 2 mm interval, obtained before surgery. We created the 3D digital model of the femur and tibia using visualization and modeling software developed in our institution. The femoral coordinate system was calculated by the 3D mechanical axis and clinical transepicondylar axis and the tibial coordinate system was calculated by the 3D mechanical axis and Akagi's line. The 3D deformities of the knee were determined by the relative position of the femorotibial coordinate system, and described by the tibial position relative to the femur. The anteversion of the femoral neck were calculated to evaluate the relationship between the valgus knee and hip region. Results. The 3D deformities of the varus knee were 12.1±5.5°varus (5.4 to 22.6°), 6.8±6.3°flexion (1.7 to 21.7°) and 6.5±6.1 °external rotation (−1.2 to 23.2°). The flexion and external rotational deformities were larger in knees with increased varus deformities. The 3D deformities of the valgus knee were 10.2±4.2°valgus (0.6 to 15.0°), 9.5±8.8°flexion (−5.2 to 23.7°) and 2.3±7.3°external rotation (−9.4 to 16.1°). Although there were no tendency about the 3D deformities in the valgus knee, the anteversion of the femoral neck in the valgus knees was 31.9°compared with 10.8°in the varus knees. Conclusion. The varus deformity in OA of the knee is associated with significant flexion and external rotational deformity. In contrast, the valgus deformity has a biomechanical background originating from the anteversion of the femoral neck

Few epidemiological studies from Asian countries have addressed this issue and reported that FAI is less prevalent in Asian population. The purpose of this study was to determine the prevalence of radiographic hip abnormalities associated with FAI in asymptomatic Korean volunteers. The authors hypothesized that the prevalence of FAI in Korean population would not be less than that in western population. Two hundred asymptomatic volunteers with no prior hip surgery or childhood hip problems underwent three-view plain radiography (pelvis anteroposterior (AP) view, Sugioka view, and 45° Dunn view) of both hips. Cam lesions were defined as the presence of the following signs on each views: pistol-grip deformity, osseous bump at the femoral head-neck junction, flattening of the femoral head-neck offset, or alpha angle >50°. Pincer lesions were determined by radiographic signs, including crossover sign, posterior wall deficient sign, or lateral center-edge (CE) angle >40°. Only positive cases agreed by both observers were defined as true FAI-related deformities. There were 146 male and 254 female hips, with a mean age of 34.7 years. On pelvis AP view, the prevalence of pistol grip deformity, bump, flattening, and alpha angle >50° was 1.3% (male 3.4%, female 0%), 0.8% (male 2.1%, female 0%), 0.8% (male 2.1%, female 0%), and 1.0% (male 2.7%, female 0%), respectively. On Sugioka view, the prevalence of bump, flattening, and alpha angle >50° was 9.8% (male 14.4%, female 7.1%), 13.5% (male 20.5%, female 9.4%), and 14.0% (male 26.7%, female 6.7%), respectively. On 45° Dunn view, the prevalence of bump, flattening, and alpha angle >50° was 8.0% (male 14.4%, female 4.3%), 17.5% (male 27.4%, female 11.8%), and 27.5% (male 44.5%, female 17.7%), respectively. The prevalence of cam lesion which was identified on at least one radiograph was 42.5% (male 62.3%, female 31.1%). The prevalence of cam lesion which was identified on ≥2 radiographs was 19.3% (male 30.8%, female 12.6%). The prevalence of cam type FAI (at least one cam lesion) was 2.0% (male 5.5%, female 0%) on pelvis AP view, 25.8% (male 37.0%, female 19.3%) on Sugioka view, and 35.8% (male 55.5%, female 24.4%) on 45° Dunn view. On pelvis AP view, the prevalence of crossover sign, posterior wall sign, and CE angle >40° was 20.0% (male 23.3%, female 18.1%), 20.8% (male 22.6%, female 19.7%), and 2.0% (male 2.7%, female 1.6%), respectively. The prevalence of pincer type of FAI (at least one pincer lesion) was 23.0% (male 27.4%, female 20.5%). In asymptomatic Korean volunteers, the prevalence of cam type FAI was low on AP pelvis radiographs, whereas the prevalence of cam type FAI on Sugioka and 45° Dunn view was found to be comparable to that previously reported in Western populations. The prevalence of pincer type FAI in asymptomatic Korean volunteers was also comparable that in Western populations and was similar in both gender. Considering the high prevalence of FAI morphologic features on plain radiographs in asymptomatic Korean populations, it is also important to determine whether FAI is a cause of hip pain when considering surgery in Asian patients

Aims

Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement.

During the preoperative examination, surgeons determine whether a patient, with a degenerative hip, is a candidate for total hip arthroplasty (THA). Although research studies have been conducted to investigate in vivo kinematics of degenerative hips using fluoroscopy, surgeons do not have assessment tools they can use in their practice to further understand patient assessment. Ideally, if a surgeon could have a theoretical tool that efficiently allows for predictive post-operative assessment after virtual surgery and implantation, they would have a better understanding of joint conditions before surgery. The objectives of this study were (1) to use a validated forward solution hip model to theoretically predict the in vivo kinematics of degenerative hip joints, gaining a better understanding joint conditions leading to THA and (2) compare the predicted kinematic patterns with those derived using fluoroscopy for each subject. A theoretical model, previously evaluated using THA kinematics and telemetry, was used for this study, incorporating numerous muscles and ligaments, including the quadriceps, hamstring, gluteus, iliopsoas, tensor fasciae latae, an adductor muscle groups, and hip capsular ligaments. Ten subjects having a pre-operative degenerative hip were asked to perform gait while under surveillance using a mobile fluoroscopy unit. The hip joint kinematics for ten subjects were initially assessed using in vivo fluoroscopy, and then compared to the predicted kinematics determined using the model. Further evaluations were then conducted varying implanted component position to assess variability. The fluoroscopic evaluation revealed that 33% of the degenerative hips experienced abnormal hip kinematics known as “hip separation” where the femoral head slides within the acetabulum, resulting in a decrease in contact area. Interestingly, the mathematical model produced similar kinematic profiles, where the femoral head was sliding within the acetabulum (Figure 1). During swing phase, it was determined that this femoral head sliding (FHS) is caused by hip capsular laxity resulting in reducing joint tension. At the point of maximum velocity of the foot, the momentum of the lower leg becomes too great for capsule to properly constrain the hip, leading to the femoral component pistoning outwards. During stance phase, kinematics of degenerative hips were similar to kinematics of a THA subject with mal-positioning of the acetabular cup. Further evaluation revealed that if the cup was placed at a position other than its native, anatomical center, abnormal forces and torques acting within the joint lead to the femoral component sliding within the acetabular cup. It was hypothesized that in degenerative hips, similar to THA, the altered center of rotation is a leading influence of FHS (Figure 2). The theoretical model has now been validated for subjects having a THA and degenerative subjects. The model has successfully derived kinematic patterns similar to subjects evaluated using fluoroscopy. The results in this study revealed that altering the native joint center is the most influential factor leading to FHS, or more commonly known as hip separation. A new module for the mathematical model is being implemented to simulate virtual surgery so that the surgery can pre- operatively plan and then simulate post-operative results

Introduction: Infants referred under the Hip Screening Programme undergo both a clinical and ultrasonic assessment of hip stability. The majority are reviewed for repeat clinical assessment and X-ray of the hips before a diagnosis of DDH will be excluded. If we could safely rely on the ultrasound findings, then the number of children routinely reviewed with a hip radiograph could be reduced. As a result, many children would avoid the unnecessary and potentially harmful exposure to radiation. In addition, the burden on both the Orthopaedic Outpatients Department and the Radiology Department could be eased. Objective: The aim of the study was to assess the sensitivity of the ultrasound screening programme for DDH over a four year period. Study Design: A retrospective review of the 501 infants referred for hip screening between January 1997 and December 2000. Results: 28 patients were treated for DDH during the period of January 1997 to December 2000. Thirteen patients (46.4%) of those treated for DDH were referred via the Hip Screening Programme after their initial baby check by the paediatricians showed that they had a risk factor. The risk factors include Family History, Breech Deliver, and clinical instability. The remaining fifteen patients (53.6%) were referred via GP’s, Health Visitors and Paediatricians, following abnormal clinical findings ranging from ‘clicky hip’, abnormal skin creases, and decreased hip abduction at follow up baby checks. The average age of the infant in this group was 5.5 months. These 15 were diagnosed with X-ray only. All patients (501 patients) referred via the Hip screening programme underwent an ultrasound scan of both hips initially, and a pelvic X-ray 4–6 months after this. We identified 5 cases where the ultrasound had originally been interpreted as normal, yet the infant developed DDH as diagnosed by a later X–ray. Five infants (38.5%) of the thirteen diagnosed with DDH via the screening programme is unacceptable. These five infants could easily have been missed until they were a lot older, and subsequently their prognoses would have been worse. Three (20%) of the fifteen patients diagnosed with DDH which were not referred via the Hip Screening Programme had an identifiable risk factor at birth, yet were not sent for orthopaedic review and ultrasound examination via the Screening Programme. Conclusion: Normal ultrasound scan does not exclude a subsequent diagnosis of Developmental Dysplasia of the hip. X-ray is still considered the gold standard in assessing a child’s hips. Both the performance and interpretation of the hip ultrasound is skill with a steep learning curve and, for the meantime, will have to go hand in hand with pelvic X-rays in diagnosing DDH

Aims

Complex total hip arthroplasty (THA) with subtrochanteric shortening osteotomy is necessary in conditions other than developmental dysplasia of the hip (DDH) and septic arthritis sequelae with significant proximal femur migration. Our aim was to evaluate the hip centre restoration with THAs in these hips.

Aim: We wanted to ascertain if clinical examination confers any additional benefit to secondary/targeted ultrasound screening of neonatal hips. Materials/Methods: Of the 30585 births (over a 6 year period) in the population served by our hospital, 2742 babies (8.96percent) were referred to the Hip Screening Clinic by the neonatologists and general practitioners. They were examined clinically and by US scans by the specialist consultants. The findings were documented prospectively. Of these, 1862 hips were normal on clinical examination, 841 hips tense (clinical examination inconclusive). Results: 233 hips were identified as abnormal by the US scans (Graf method). 106 (45percent) of these were normal on clinical examination. In 88 of the hips with abnormal US scans (38percent), clinical examination could not be performed reliably as the babies were tense. None of the hips identified as abnormal on clinical examination were normal on US scans. Conclusion/Discussion: US scanning of hips in at-risk babies by an experienced paediatric radiologist will identify all the abnormal hips. This will release the paediatric orthopaedic surgeon from routine clinical examination of all these babies. This time can be utilised for running other clinics. Babies found to have abnormal hips on US scanning may be seen by the orthopaedic surgeon for treatment and follow-up. Parents of babies with normal hip US scans may be reassured by a nurse practitioner or a paediatric physiotherapist. This should lead to better utilisation of resources and cost savings

Aim: We wanted to ascertain if clinical examination confers any additional benefit to secondary/targeted ultrasound screening of neonatal hips. Materials and Methods: Of the 30585 births (from 1997–2002) in the population served by our hospital, 2742 babies (8.96 percent) were referred to the Hip Screening Clinic by the neonatologists and general practitioners. They were examined clinically and by US scans by the specialist consultants. The findings were documented prospectively. Of these, 1862 hips were normal on clinical examination, 841 hips tense (clinical examination inconclusive). Results: 233 hips were identified as abnormal by the US scans (Graf method). 106 (45 percent) of these were normal on clinical examination. In 88 of the hips with abnormal US scans (38 percent), clinical examination could not be performed reliably as the babies were tense. None of the hips identified as abnormal on clinical examination were normal on US scans. Conclusion/Discussion: US scanning of hips in at-risk babies by an experienced paediatric radiologist will identify all the abnormal hips. This will release the paediatric orthopaedic surgeon from routine clinical examination of all these babies. This time can be utilised for running other clinics. Babies found to have abnormal hips on US scanning may be seen by the orthopaedic surgeon for treatment and follow-up. Parents of babies with normal hip US scans may be reassured by a nurse practitioner or a paediatric physiotherapist. This should lead to better utilisation of resources and cost savings

Labral tears can lead to disabling hip pain however underlying structural (femoroacetabular impingement) and developmental abnormalities predisposing to labral pathology may be left untreated if the peripheral compartment is ignored during hip arthroscopy. Femoroace-tabular impingement (FAI) can be secondary to abnormal morphologic features involving either the proximal femur and/or the acetabulum. Both acetabular labral tears and FAI lead to premature osteoarthritis of the hip. Early diagnosis and treatment of these hip pathologic abnormalities is important, not only to provide pain relief but also to prevent the development of osteoarthritis. Purpose: To describe the technique for arthroscopy of the peripheral compartment of the hip joint without traction. Methods: We performed 9 hip arthroscopies without traction from a lateral and and anterolateral portals in the supine position. After a traditional central arthroscopy with traction, 60 degrees of flexion at the hip joint without traction allowed relaxation of the anterior capsule and increased the intra-articular volume of the peripheral compartment. Results: Inspection of the peripheral compartment was obtained from the anterolateral portal. The anterior neck area, medial neck area, medial head area, anterior head area, lateral head area and lateral neck area were viewed. In 3 patients, loose bodies were removed. In 1 patient with PVNS synovial biopsy was taken and synovectomy was performed. Osteochondroplasty was performed in 5 patients for femoroacetabular impingement. No complications were observed. Conclusions: Hip arthroscopy without traction is mandatory to complete assessment and adequate treatment of the painful hip

Purpose: The purpose of this study was to evaluate a possible correlation between DDH and lumbosacral spina bifida occulta (LSSBO). Patients and Methods: This multicentric study included the assessment of anteroposterior pelvic radiographs of 415 adolescents and adults without any bilateral clinical and radiological hip joint abnormality and of latest radiographs of 291 adolescent and adult patients who had treated or untreated DDH which had occured unilaterally or bilaterally. Control group included 332 females and 83 males and mean age was 38±17 (12-70) years. DDH group included 246 females and 45 males and mean age was 30±17 (12-80) years. Results: Female/male ratio of both groups was statistically similar (p=0.124). Rate of LSSBO was 12% and 23% in the control and DDH groups, respectively (p< 0.001). S1 and L5 vertebrae were the two most common involved sites in both groups. There wasn’t any significant correlation between the rate of LSSBO and the involved hip side in the DDH group (p=0.336). In females, rate of LSSBO was 9% and 23% in the control and DDH groups, respectively (p< 0.001). In males, rate of LSSBO was 22% and 24% in the control and DDH groups, respectively (p=0.893). Conclusion: In females, DDH is significantly accompanied by LSSBO and LSSBO may be considered as a risk factor for DDH. Further intrauterine studies are needed for better understanding of this fact. It may be better to perfom ultrasonographic hip screening for the newborns who has an evident posterior vertebral arch defect without any intraspinal anomaly which has been seen during fetal ultrasonography

Introduction and Aims: There is a relationship between the anatomy of the hip joint and the development of arthritis. A common cause of hip pain in the young adult that can lead to arthritis is acetabular dysplasia. More recently, femoroacetabular impingement has been described as another cause of hip pain. The purpose of our study was to evaluate the applicability of pelvic computed tomography (CT) with three-dimensional surface rendering to evaluate femoro-acetabular impingement. Method Thirty-six hips (30 patients; 17 males; 13 females) with persistent hip pain, mean age 41 (37–52), underwent three-dimensional CT of the pelvis, as well as MRI arthrography with gadolinium enhancement. On 3D CT, the concavity of the femoral head-neck junction (offset), alpha angle as described by Notzli was calculated to depict the anterior femoral neck contour. The concavity of the posterior aspect of the head neck junction was measured as the beta angle. The same measurements were made in 20 hips, consisting of randomly selected patients with no prior history of hip pathology or pain (mean age 37; 13 males; eight females). Results The mean alpha angle for the symptomatic group was 66.4 (39–94) and 43.8 (39.3–48.3) for the control group (p=0.001). All symptomatic hips had abnormal findings on MRA: labral tears in all; cartilage delamination/ulceration in 14 hips; herniation pits in six hips. The majority of labral tears and delamination were located in the antero-superior quadrant. In the surgical treated group, all MRA findings were confirmed. The mean beta angle was significantly smaller (increase concavity) in the symptomatic versus the controls: 40.2 versus 43.8 (p=0.011). Interestingly in the symptomatic group the beta angle was significantly lower than the alpha angle (p< 0.02), but not in the controls. Conclusion: 3D CT with surface rendering and multiplanar reformation is useful to determine degree of bone buttressing of the anterior femoral head-neck junction quantitatively assessed by alpha angle measurement, which is elevated in patients with femoro-acetabular impingement. With a greater posterior concavity i.e. small beta angle in the symptomatic group versus the control, subclinical slipped femoral epiphysis remains a plausible cause of this deformity

Objectives

Normal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population.

The August 2012 Hip & Pelvis Roundup³⁶⁰ looks at: whether cemented hip replacement might be bad for your health; highly cross-linked polyethylene; iHOT-33 - a new hip outcome measure; hamstring injuries; total hip replacement; stemmed metal-on-metal THR; bipolar hemiarthroplasty, neuromuscular disease and dislocation; the high risk of secondary hemiarthroplasty; and whether we have to repair the labrum after all?

The October 2013 Hip & Pelvis Roundup³⁶⁰ looks at: Young and impinging; Clothes, weather and femoral heads?; Go long, go cemented; Surgical repair of the abductors?; Aspirin for DVT prophylaxis?; Ceramic-on-polyethylene: a low-wear solution?; ALVAL and ASR™: the story continues….; Salvaging Legg-Calve-Perthes’ disease

The June 2012 Spine Roundup³⁶⁰ looks at: back pain; spinal fusion for tuberculosis; anatomical course of the recurrent laryngeal nerve; groin pain with normal imaging; the herniated intervertebral disc; obesity’s effect on the spine; the medicolegal risks of cauda equina syndrome; and intravenous lidocaine use and failed back surgery syndrome.