Total Hip Arthroplasty in Protrusio Acetabuli: A Systematic Review.

Protrusio acetabuli, or abnormal protrusion of the femoral head into the acetabulum, requires performance of a total hip arthroplasty (THA) for which various reconstruction techniques and outcomes have been described. The aim of this systematic review is to provide a comprehensive analysis of the current evidence, evaluate treatment efficacy, compare surgical techniques, and identify topics for future research along with improving evidence-based decision-making, improving patient outcomes in the management of this condition. A thorough systematic review of the PubMed, Embase, Cochrane Library databases, and Scopus library was conducted, and articles describing techniques of THA for treatment of protrusion acetabuli were extracted. The initial search generated 751 results. After exclusion, 18 articles were included. Of these, eight were prospective studies and 10 were retrospective. Surgery was performed on 783 hips with a mean age of 60 years; 80% of females who mostly had inflammatory arthritis were followed up for 8.86 years (range, 2-15.4 years). Good outcomes have been achieved with THA using uncemented cups with bone graft; however, no conclusion could be drawn with regard to the femoral side. It can be concluded that the concept of restoration of the anatomical hip center of rotation is paramount for good outcome and better survival of the implant is important when using uncemented cups with a bone graft. In addition, screw augmentation for fixation is not recommended unless absolutely necessary. The most common complications were aseptic loosening and heterotopic ossification. While the former required revision, conservative management was administered for the latter.

Protrusio acetabuli in tubercular hip: Outcome of femoral head as autologous bone graft used during total hip replacement.

Purpose: Here we present a study of a tuberculosis hip protrusion with a large acetabular defect treated by total hip replacement using a novel technique without the use of any protrusio ring, wire mesh, or cage. To our knowledge, such a technique has not been described in the literature previously. Methodology: 25 patients with a past treatment history of hip tuberculosis came to our medical college with complaints of worsening pain in the hip joint and limping. The hip pain and limping were progressive in nature and became more severe, and his affected lower limb shortened. Results: The average AK distance (horizontal distance between Kohlar line and the medial acetabular border) before surgery was 8 mm (range: 1-16). For the acetabular implant, the mean abduction angle was 45° (range: 41-48), and the mean anteversion angle was 18° (range: 13-24). The average preoperative shortening for limb length inequality was 4 mm (range: 0-11). The average HHS (Harris Hip Score) during follow-up was 87.6 points. Conclusion: In TB hip protrusio, an autograft of the femur head is used to fill the acetabular defect and provide a good approach for these patients without any extra economic burden or complications as seen in a metallic ring or cage.

The Direct Anterior Approach (DAA) as a Standard Approach for Total Hip Arthroplasty (THA) in Coxa Profunda and Protrusio Acetabuli? A Radiographic Analysis of 188 Cases.

INTRODUCTION: The direct anterior approach (DAA) represents a well-recognized soft tissue sparing technique for primary total hip arthroplasty (THA). The feasibility and suitability of the DAA in cases of complex acetabular deformities, namely coxa profunda (CP) and protrusio acetabuli (PA), remain to be determined. METHODS: A total of 188 cases of CP (100 cases) and PA (88 cases) hips undergoing primary THA via the DAA were retrospectively analyzed. Surgical and radiographic parameters were evaluated and potential complications were assessed. Finally, successful implantation was defined if surgical and radiographic parameters were well within established values of non-complex primary THA. RESULTS: In 159 hips, the medial border of the acetabular component was transferred laterally to the ilioischial line, corresponding to a fully treated acetabular protrusion. In 23 (12.23%) cases, mild, and in 5 (2.66%) cases, moderate residual acetabular protrusion remained after THA. Postoperatively, 11.40% (PA group) and 9.00% (CP group) had a leg length discrepancy (LLD) greater than 10 mm. The mean operative time was significantly less than 60 min. A linear relationship between the BMI and operative time was observed, with an additional 0.9 min of operative time per BMI unit. Overall, complications were rare and did not differ between the two groups. CONCLUSION: The results of this study suggest that the DAA is a suitable approach for primary THA in patients with coxa profunda and acetabular protrusion if performed by experienced surgeons familiar with the DAA. Obese patients with acetabular protrusion may pose a significant limitation to the DAA and caution should be advised in cases of obesity.

Outcomes of Total Hip Replacement for Failed Hemiarthroplasty.

Aim: Our study aims to analyze the outcomes of conversion total hip replacement (THR) done for failed hemiarthroplasty. Patients and Methods: We retrospectively analyzed 104 consecutive patients who underwent conversion THR for failed hemiarthroplasty between January 2012 and December 2018. The patient's records were analyzed for demographic information, index surgery details, preoperative functional status, and perioperative complications. Patients were analyzed according to the various modes of failure of hemiarthroplasty. The radiographs were analyzed for any progressive osteolysis, cup migration and stem subsidence. All the patients were evaluated using the modified Harris hip score (HHS) for clinical outcome. Complications, revision or reoperation in the follow-up period was recorded. Results: A total of 73 patients were included in the study for final analysis after exclusion criteria. The average follow-up was 48.2 ± 29.6 months. There was a significant improvement in mean HHS from 38.5 ± 9.1 preoperatively to 80.9 ± 4.3 at the last follow-up (p < 0.05). The different modes of failure had no statistically significant difference in the postoperative Harris hip score (p = 0.393). None of the patients had progressive radiolucent lines more than 2 mm or significant subsidence in the final follow-up compared to the initial postoperative radiograph. There was one deep infection, one patient had grade 2 heterotopic ossification, intraoperative calcar fracture was fixed with cerclage wiring in 11 patients, and postoperative periprosthetic fracture in two patients was treated with plate osteosynthesis. There were no neurovascular complications or dislocation during the follow-up. Conclusion: Conversion THR for failed hemiarthroplasty is a challenging procedure and results in good functional outcome and provides reliable pain relief. Conversion THA for septic loosening by two stage revision have comparable postoperative outcomes like THA for aseptic loosening. Caution is required owing to high incidence of peri-prosthetic fracture during conversion THA. Dislocation rate is negligible even with smaller head provided the prosthesis is implanted in the proper orientation and adequate soft tissue balancing is achieved.

Pertrochanteric fracture of an ankylosed hip with protrusio acetabuli treated by PFNA nail: A case report of a rare case.

INTRODUCTION: Hip fractures are the cause of significant morbidity and mortality, aggravated by the existence of an underlying hip pathology. The association of a pertrochanteric fracture with an ankylosed hip and acetabular protrusion is extremely rare. It has not been reported in the literature and the optimal management remains unknown. The surgical treatment indicated for trochanteric fractures allows patients to restore their autonomy quickly while avoiding complications. CASE PRESENTATION: We present the case of a 45-year-old patient who was followed for multiple myeloma and treated with chemotherapy. Following a fall on the pelvis, we found a pertrochanteric fracture with an ankylosed hip and acetabular protrusion. The patient was treated with a PFNA nail based on some principles to improve stabilization, with good results. CLINICAL DISCUSSION: The combination of acetabular protrusion and hip ankylosis alters the biomechanics of this joint by displacing the center of rotation inward and decreasing abductor muscle tension while increasing the lever arm. Several surgical approaches have been reported on case reports with different results. No consensus has been reached for this entity because of its rarity and the absence of a large sample. The result reported for our patient could make cephalomedullary nailing a good option since it allows preservation of the gluteal musculature, early management of the patient and recovery of the pre-morbid state. CONCLUSION: The lack of consensus and the changes caused by this hip condition are a challenge for orthopedists. We treated our patient with a PFNA nail based on a few principles necessary to optimize stability with a satisfactory result.

Is Restoration of Hip Center Mandatory for Total Hip Arthroplasty of Protrusio Acetabuli?

Purpose: While initial fixation using a press-fit of the acetabular cup is critical for the durability of the component, restoration of the hip center is regarded as an attributable factor for implant survival and successful outcome. In protrusio acetabuli (PA), obtaining both restoration of the hip center and the press-fit of the acetabular cup simultaneously might be difficult during total hip arthroplasty (THA). We tested the hypothesis that use of a medialized cup, if press-fitted, will not result in compromise of the implant stability and outcome after cementless THA of PA. Materials and Methods: A total of 26 cementless THAs of 22 patients with PA were reviewed. During THA, press-fit of the cup was prioritized rather than hip center restoration. A press-fit was obtained in 24 hips. A press-fit could not be obtained in the two remaining hips; therefore, reinforcement acetabular components were used. Restoration of the hip center was achieved in 17 cups; 15 primary cups and two reinforcement components; it was medialized in nine cups. Implant stability and modified Harris hip score (mHHS) between the two groups were compared at a mean follow-up of 5.1 years (range, 2-16 years). Results: Twenty-six cups; 17 restored cups and nine medialized press-fitted cups, remained stable at the latest follow-up. A similar final mHHS was observed between the restored group and the medialized group (83.6±12.1 vs 83.8±10.4, P=0.786). Conclusion: Implant stability and favorable results were obtained by press-fitted cups, irrespective of hip center restoration. THA in PA patients showed promising clinical and radiological results.

Protrusio acetabular en artroplastía total de cadera: diez tácticas para un buen resultado quirúrgico / Total hip arthroplasty in protrusio acetabuli: ten tips to improve surgical outcomes

Los pacientes candidatos a artroplastía total de cadera con protrusio acetabular asociada generan distintos desafíos en los equipos quirúrgicos. Múltiples estrategias han sido utilizadas a lo largo de los años para optimizar los resultados. Mediante una revisión de la evidencia actualizada disponible, proponemos diez tácticas a realizar en el manejo de estos pacientes que pueden mejorar y hacer predecible el tratamiento de un paciente con protrusio acetabular al que se le realiza una artroplastía total de cadera. Nivel de Evidencia V.

Patients with acetabular protrusio and osteoarthritis are a challenge for the surgical team. Many strategies have been developed to anticipate, plan and optimize the surgical results of these patients. Based on the current available clinical evidence, we propose ten tips to improve the surgical management of hip arthroplasty patients with protrusio acetabuli. Level of Evidence V.

Managing Protrusio Acetabuli With a Direct Anterior Approach Total Hip Replacement.

Introduction The deformities of protrusio acetabuli (PA) present unique reconstructive challenges. An incarcerated femoral head, medialized center of rotation, deficient bone stock, and associated leg length discrepancy add significant technical complexity to total hip arthroplasty (THA). Methods We retrospectively reviewed 23 THAs in 21 patients with PA who underwent direct anterior (DA) approach THA with intraoperative fluoroscopy. All acetabular defects were reconstructed with morcellized femoral head autograft using Bone Mill (Stryker Corporation, Kalamazoo, MI). Results The mean AK distance preoperatively was 8 mm (range: 1-16). Postoperatively, the degree of protrusio improved in all cases, and the mean AK distance decreased to 0 mm. All bone grafts consolidated, and no cups loosened or were revised at a mean of 5.3 years of follow-up. The mean Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS, JR) at follow-up was 91. Conclusions These data suggest that the DA approach with intraoperative fluoroscopy may be a reasonable technique in the surgical management of this challenging population.

[How I explore... protrusio acetabuli in children]. / Comment j'explore le protrusio acetabuli chez l'enfant.

Protrusio acetabuli is a clinical entity with variable clinical presentation consisting of a medial deviation of the acetabulum in the pelvic direction. Qualified as a silent deformity in view of its asymptomatic nature until the onset of early degenerative changes, the patient will present with progressive joint pain and stiffness until the development of secondary osteoarthritis. In view of the potentially destructive primary causes associated with the development of secondary protrusion acetabuli, the radiological demonstration of this pathology in young patients cannot be neglected and should lead to the investigation of the underlying pathologies associated with this anomaly. This entity must generate regular clinical and radiological monitoring, and potentially multidisciplinary approach in the event of the appearance of diagnostic criteria for Marfan syndrome, which may vary over time and across individuals.

Le protrusio acetabuli (PA) est une entité clinique à présentation clinique variable consistant en une déviation médiale de l'acétabulum en direction pelvienne. Qualifiée de déformation silencieuse au vu de son caractère asymptomatique jusqu'à la survenue de modifications dégénératives précoces, le patient présentera une douleur et raideur articulaire progressivement évolutive jusqu'au développement d'une coxarthrose secondaire. Au vu des causes primaires potentiellement destructrices associées au développement d'un PA secondaire, la mise en évidence radiologique de cette pathologie chez le patient jeune ne peut être négligée et doit faire rechercher les pathologies sous-jacentes associées à cette anomalie. Cette entité doit également engendrer un suivi clinique et radiologique régulier, et potentiellement multidisciplinaire en cas d'apparition de critères de diagnostic du syndrome de Marfan, variables en fonction du temps et des individus.

Cutibacterium acnes Infection of Hip Bipolar Hemiarthroplasty Resulting in Protrusio Acetabuli: A Case Report and Review of Literature.

Introduction: Hip bipolar hemiarthroplasty is commonly done for elderly patients who suffer from femoral neck fractures, with good functional outcomes. Prosthetic acetabular protrusio is a rare complication following bipolar hemiarthroplasty and can occur in prosthetic joint infections (PJIs) due to destructive osteolysis and resorption of surrounding bone. Among PJI pathogens, Cutibacterium acnes is increasingly being implicated. In our paper, we review the current literature of C. acnes PJIs and report a unique case of C. acnes infection of hip bipolar hemiarthroplasty complicated by protrusio acetabuli. Case Report: The patient is a 77-year-old Asian-Chinese man who suffered from left hip pain 10 years after bipolar hemiarthroplasty surgery. Radiographic evaluation showed acetabular protrusio with extensive femoral osteolysis. Subsequent intraoperative cultures revealed C. acnes infection. The patient successfully underwent antibiotic treatment and a two-staged revision total hip arthroplasty. Conclusion: C. acnes is an increasingly recognized cause of PJIs and can cause significant morbidity. It should not be simply regarded as a contaminant of tissue or cultures. C. acnes PJIs require antibiotic treatment and early surgery with debridement and revision. This reported case presented technical challenges due to the infection resulting in prosthetic acetabular protrusio.

Location of Intra- and Extra-articular Hip Impingement Is Different in Patients With Pincer-Type and Mixed-Type Femoroacetabular Impingement Due to Acetabular Retroversion or Protrusio Acetabuli on 3D CT-Based Impingement Simulation.

BACKGROUND: Diagnosis and surgical treatment of hips with different types of pincer femoroacetabular impingement (FAI), such as protrusio acetabuli and acetabular retroversion, remain controversial because actual 3-dimensional (3D) acetabular coverage and location of impingement cannot be studied via standard 2-dimensional imaging. It remains unclear whether pincer hips exhibit intra- or extra-articular FAI. PURPOSE: (1) To determine the 3D femoral head coverage in these subgroups of pincer FAI, (2) determine the impingement-free range of motion (ROM) through use of osseous models based on 3D-computed tomography (CT) scans, and (3) determine the osseous intra-and extra-articular 3D impingement zones by use of 3D impingement simulation. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This is a retrospective, comparative, controlled study involving 70 hips in 50 patients. There were 24 patients (44 hips) with symptomatic pincer-type or mixed-type FAI and 26 patients (26 hips) with normal hips. Surface models based on 3D-CT scans were reconstructed and compared for hips with acetabular retroversion (30 hips), hips with protrusio acetabuli (14 hips), and normal asymptomatic hips (26 hips). Impingement-free ROM and location of impingement were determined for all hips through use of validated 3D collision detection software based on CT-based 3D models. No abnormal morphologic features of the anterior iliac inferior spine were detected. RESULTS: (1) Mean total femoral head coverage was significantly (P < .001) increased in hips with protrusio acetabuli (92% ± 7%) and acetabular retroversion (71% ± 5%) compared with normal hips (66% ± 6%). (2) Mean flexion was significantly (P < .001) decreased in hips with protrusio acetabuli (104°± 9°) and acetabular retroversion (116°± 6°) compared with normal hips (125°± 13°). Mean internal rotation in 90° of flexion was significantly (P < .001) decreased in hips with protrusio acetabuli (16°± 12°) compared with normal hips (35°± 13°). (3) The prevalence of extra-articular subspine impingement was significantly (P < .001) higher in hips with acetabular retroversion (87%) compared with hips with protrusio acetabuli (14%) and normal hips (0%) and was combined with intra-articular impingement. The location of anterior impingement differed significantly (P < .001) between hips with protrusio acetabuli and normal hips. CONCLUSION: Using CT-based 3D hip models, we found that hips with pincer-type and mixed-type FAI have significantly larger femoral head coverage and different osseous ROM and location of impingement compared with normal hips. Additionally, intra- and extra-articular subspine impingement was detected predominantly in hips with acetabular retroversion. Acetabular rim trimming during hip arthroscopy or open surgical hip dislocation should be performed with caution for these hips. Patient-specific analysis of location of impingement using 3D-CT could theoretically improve diagnosis and planning of surgical treatment.

Bilateral fractures of acetabulum in a young girl with osteogenesis imperfecta and epilepsy.

We report a case of bilateral displaced acetabular fractures including both columns fractures with protrusio acetabuli in a female patient, aged 15 years, with osteogenesis imperfecta (OI) (Sillence Type I), epilepsy, blue sclera and bilateral ipoacusia. Since OI is a rare genetic disorder characterized by an increased propensity to osteopenia, intraoperative fracture risks and hemorrhagic diathesis, we opted for the open reduction and internal fixation of the acetabula in two surgical steps and using two different approaches. Although the clinical outcomes are not excellent in this report (HHS 45/100), the authors suggest that chances of a good outcome with reconstruction of the acetabulum must be balanced against the benefits of early or late total hip arthroplasty. The goal was to delay a joint replacement as long as possible due to the patient's young age. Level of evidence: V, case report.

Acetabulum Protrusion Following Ceramic Liner Fracture: A Case Report.

Hip arthroplasty is an extremely satisfying treatment method for coxarthrosis which is in increasing use throughout the world. However, loosening of the prosthesis is a significant complication and to overcome this, ceramic liners are increasingly being selected. If the survival of ceramic surfaces is prolonged, there is a risk of fracture of the ceramic materials. New ceramic materials developed to overcome this problem are more resistant. The case presented here is of a patient in whom liner fracture developed following ceramic-ceramic hip arthroplasty. The ceramic femoral head was observed to have protruded into the defect created in the acetabular component. Acetabular revision was applied to the patient.

Acetabulum Protrusion Following Ceramic Liner Fracture: A Case Report

@#Hip arthroplasty is an extremely satisfying treatment method for coxarthrosis which is in increasing use throughout the world. However, loosening of the prosthesis is a significant complication and to overcome this, ceramic liners are increasingly being selected. If the survival of ceramic surfaces is prolonged, there is a risk of fracture of the ceramic materials. New ceramic materials developed to overcome this problem are more resistant. The case presented here is of a patient in whom liner fracture developed following ceramic-ceramic hip arthroplasty. The ceramic femoral head was observed to have protruded into the defect created in the acetabular component. Acetabular revision was applied to the patient.

Analysis of Protrusio Acetabuli Using a CT-based Diagnostic Method in Korean Patients with Marfan Syndrome: Prevalence and Association with Other Manifestations.

A new CT-based diagnostic method of protrusio acetabuli (PA) was introduced. However, prevalence of PA by this method and correlation between PA and other manifestations of Marfan syndrome (MFS) is unknown in Korean MFS patients. This study aimed to investigate the prevalence of PA diagnosed by a CT-based method in Korean patients with MFS, the association of PA with other manifestations of MFS, and the contribution of PA to MFS diagnosis. We retrospectively reviewed the records of 146 MFS patients with the presence of a causative FBN1 mutation and 146 age- and sex-matched controls from a single tertiary care center. All MFS patients underwent a complete assessment of criteria based on the revised Ghent nosology. PA was assessed quantitatively using a CT-based circle-wall distance (CWD) method. PA was diagnosed in 77.4% of patients in the MFS group and in 11.0% of the control group. CWD was significantly different between the two groups (1.50 mm vs. -0.64 mm, P<0.001). The presence of PA did not correlate with the presence of ectopia lentis, aortic root diameter, or history of aortic dissection. The presence of PA did not have a significant impact on the final diagnosis of MFS. Even though the presence of PA does not related to the cardinal clinical features of MFS or influence MFS diagnosis, its presence may be helpful for the suspicion of MFS when aortic dissection or aneurysm is found on CT angiography of the aorta because of the high frequency of PA in MFS patients.

Complications Encountered with Total Hip Arthroplasty in Rheumatoid Patients.

Rheumatoid arthritis affects around 1% of the global population with a predilection for Western societies. The treatment of the rheumatoid hip has gone through significant changes in recent years. Although osteotomies and synovectomies were previously commonplace, advances in arthroplasty technique and technology has seen these former procedures being performed less commonly. This article tackles some of the key issues with regard to the rheumatoid hip, namely the increased risk and methods of dealing with protrusio acetabuli, the risk of dislocation, infection and rates of aseptic loosening.

Protrusio acetabuli: joint loading with severe pincer impingement and its theoretical implications for surgical therapy.

Severe pincer impingement (acetabular protrusio) is an established cause of hip pain and osteoarthritis. The proposed underlying pathomechanism is a dynamic pathological contact of the prominent acetabular rim with the femoral head-neck junction. However, this cannot explain the classically described medial osteoarthritis in these hips. We therefore asked: (1) Does an overload exist in the medial aspect of the protrusio joint? and (2) What is the influence of three contemporary joint-preserving procedures on load distribution in protrusio hips? In vivo force and motion data for walking and standing to sitting were applied to six 3D finite element models (normal, dysplasia, protrusio, acetabular rim trimming, acetabular reorientation, and combined reorientation/rim trimming). Compared with dysplasia, the protrusio joint resulted in opposite patterns of von Mises stress and contact pressure during walking. In protrusio hips, we found an overload at the medial margin of the lunate surface (54% higher than normal). Isolated rim trimming further increased the medial overload (up to 28% higher than protrusio), whereas acetabular reorientation with/without rim trimming reduced stresses by up to 25%. Our results can be used as an adjunct for surgical decision making in the treatment of acetabular protrusio.

Analysis of Protrusio Acetabuli Using a CT-based Diagnostic Method in Korean Patients with Marfan Syndrome: Prevalence and Association with Other Manifestations

A new CT-based diagnostic method of protrusio acetabuli (PA) was introduced. However, prevalence of PA by this method and correlation between PA and other manifestations of Marfan syndrome (MFS) is unknown in Korean MFS patients. This study aimed to investigate the prevalence of PA diagnosed by a CT-based method in Korean patients with MFS, the association of PA with other manifestations of MFS, and the contribution of PA to MFS diagnosis. We retrospectively reviewed the records of 146 MFS patients with the presence of a causative FBN1 mutation and 146 age- and sex-matched controls from a single tertiary care center. All MFS patients underwent a complete assessment of criteria based on the revised Ghent nosology. PA was assessed quantitatively using a CT-based circle-wall distance (CWD) method. PA was diagnosed in 77.4% of patients in the MFS group and in 11.0% of the control group. CWD was significantly different between the two groups (1.50 mm vs. -0.64 mm, P<0.001). The presence of PA did not correlate with the presence of ectopia lentis, aortic root diameter, or history of aortic dissection. The presence of PA did not have a significant impact on the final diagnosis of MFS. Even though the presence of PA does not related to the cardinal clinical features of MFS or influence MFS diagnosis, its presence may be helpful for the suspicion of MFS when aortic dissection or aneurysm is found on CT angiography of the aorta because of the high frequency of PA in MFS patients.

Acetabular protrusio: surgical technique of dealing with a problem in depth.

There are few reports describing the technique of managing acetabular protrusio in primary total hip replacement. Most are small series with different methods of addressing the challenges of significant medial and proximal migration of the joint centre, deficient medial bone and reduced peripheral bony support to the acetabular component. We describe our technique and the clinical and radiological outcome of using impacted morsellised autograft with a porous-coated cementless cup in 30 primary THRs with mild (n = 8), moderate (n = 10) and severe (n = 12) grades of acetabular protrusio. The mean Harris hip score had improved from 52 pre-operatively to 85 at a mean follow-up of 4.2 years (2 to 10). At final follow-up, 27 hips (90%) had a good or excellent result, two (7%) had a fair result and one (3%) had a poor result. All bone grafts had united by the sixth post-operative month and none of the hips showed any radiological evidence of recurrence of protrusio, osteolysis or loosening. By using impacted morsellised autograft and cementless acetabular components it was possible to achieve restoration of hip mechanics, provide a biological solution to bone deficiency and ensure long-term fixation without recurrence in arthritic hips with protrusio undergoing THR.