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Over the last decade, evidence has mounted for a prominent etiologic role of femoroacetabular impingement (FAI) in the development of early hip osteoarthritis (OA). The aim of this study was to compare the ultrastructure and tissue composition of the hip labrum in healthy and pathological conditions, as FAI and OA, to provide understanding of structural changes which might be helpful in the future to design targeted therapies and improve treatment indications. We analyzed labral tissue samples from five healthy multi-organ donors (MCDs) (median age, 38 years), five FAI patients (median age, 37 years) and five late-stage OA patients undergoing total hip replacement (median age, 56 years). We evaluated morpho-functional by histology and transmission electron microscopy. Extracellular matrix (ECM) structure changes were similar in specimens from FAI compared to those from patients with OA (more severe in the latter) showing disorganization of collagen fibers and increased proteoglycan content. In FAI and in OA nuclei the chromatin was condensed, organelle degenerated and cytoplasm vacuolized. Areas of calcification were mainly observed in FAI and OA labrum, as well as apoptotic-like features. We showed that labral tissue of patients with FAI had similar pathological alterations of tissue obtained from OA patients, suggesting that FAI patients might have high susceptibility to develop OA.

Objective: Stem anteversion in total hip arthroplasty (THA) has been measured using two different distal references, the posterior condyle (PC) or the transepicondylar axis (TEA). The reliability, the difference in value between these two techniques, and the possible confounding factors are scarcely known. Aims of this work were to assess (1) the intraclass correlation and the difference between the two measurement techniques and (2) the possible influence of condylar dysmorphisms on the anteversion value discrepancy. Materials and methods: A consecutive series of post-THA CT scans were selected, excluding hip dysplasia, end-stage knee osteoarthritis, and replaced knees. Using a surgical planning software, stem anteversion was measured using the PC or the TEA reference. The intraclass reliability was assessed. The anteroposterior femoral condyle diameters were measured: the difference and the ratio were measured and correlated with the stem anteversion values. Results: 91 CT scans were included. Inter/intra-observer TEA measurements were more reliable than PC. The intraclass correlation between PC and TEA anteversion measurements was good, 0.954 (CI 95% 0.922–0965). The mean difference between PC and TEA anteversion was 5.27 ± 2.41°. The difference and the ratio between the two anteroposterior condyle diameters did not influence the anteversion difference (respectively, p 0.797 and p 0.901). Conclusions: TEA and PC demonstrated to achieve a good correlation, not dependent from the condyle morphology. However, the difference between the two measurements (5°) can severely influence the combined anteversion (10–20%): due to clinical applicability and better inter/intra-observer agreement, TEA should be preferred for measuring stem anteversion.

Introduction: Total hip arthroplasty (THA) is the standard procedure for post-traumatic osteoarthritis (OA) of the hip after acetabular fracture. However, it is not as simple as a primary THA, challenging the surgeon with anatomical deformity and intra and postoperative complications. In the current literature, there is a lack of studies reporting long-term results. May ceramic-on-ceramic (CoC) bearings provide good clinical and radiological outcomes at a long-term follow-up in patients undergoing THA following acetabular fracture? Materials and methods: We retrospectively analyzed 68 patients (mean age 47years [range 22–75)] who underwent cementless modular neck stem THA, all implants CoC bearings (50 previously operatively treated and 18 non-operatively treated) after a specific CT study protocol at our Institute since 2000–2008. Clinical outcomes, prosthetic components’ osseointegration, survival rate, and reasons for revision were analyzed. Minimum clinical and radiological follow-up was 10years. Results: HHS improved significantly after surgery from 37.6 ± 14.1 to 88.4 ± 11.6. 8 revision surgeries were performed, none for infection: we reported 2 stem aseptic loosening, 2 periprosthetic femoral fractures and 4 modular neck fractures. One implant noise (third-generation ceramic coupling) was described. Cup osseointegration was present (according to Moore the presence of at least 3 radiological criteria defines an effective osseointegration) in 67 patients (98.5%). After a 10years follow-up, survival rate resulted 88.4%, sensibly higher than most of results reported in the current literature. Conclusion: The high survival rate may be related to CoC: no osteolysis and no infections were reported. Also acetabular cup loosening incidence was sensibly lower (1.47%) among loosening rate described by other authors. Clinical and radiological outcomes were decent, probably due to modular prosthesis design. Modular necks are a solution which can help achieving a proper functional reconstruction of the hip (offset, center of rotation), but should be avoided in young and overweight patients because of the high risk of fracture. CoC bearings in THAs in post-traumatic OA after acetabular fracture showed good results despite the fact that specific ceramic-related issues have to be considered.

Cup overhanging in total hip arthroplasty is a predisposing factor to iliopsoas impingement. In dysplastic hips, cup implantation was simulated in an anatomic hip center of rotation (AHCR) and in high hip center (HHCR). We sought to assess: (1) the percentage of prominent cups; (2) quantify the cup protrusion at different sites on frontal, axial and sagittal views. In 40 Crowe III-IV hips, using a 3D CT-based planning software, cup planning in AHCR and HHCR (CR height ≥ 20 mm) was performed for every hip. Cup prominence was assessed on every plane. HHCR cups were less anteverted (p < 0.01), less medialized (p < 0.001) and less caudal (p = 0.01) than AHCR sockets. AHCR cups were more frequently prominent on at least one plane (92.5% vs. 77.5%), with minimal agreement between the two configurations (k = 0.31, p = 0.07). AHCR cups protruded more than HHCR sockets in the sagittal (p = 0.02) and axial planes (p < 0.001). Axially, at the center of the cup, prominence 6–11 mm occurred in nine (22.5%) AHCR and one (2.5%) HHCR socket. In conclusion, while a routine high hip center should not be recommended, cup placement at a center of rotation height < 20 mm is associated with higher rates and magnitudes of anterior cup protrusion in severe dysplasia.

Objective: In developmental hip dysplasia (DDH) patients, the chronic dislocation of the femoral head with respect to the true acetabulum determines muscle contracture and atrophy, particularly of the abductor muscles, and leads to secondary osteoarthritis (OA) with severe motor dysfunction, pain and disability. The correct positioning when a total hip replacement (THR) is performed is fundamental to the recovery of gait function. Also, inadequate rehabilitation of the abductor muscles for pelvic stabilisation can be responsible for residual dysfunction. Consensus on a programme for abductor muscle strengthening in these patients is not currently available. The aim of this study was to evaluate the effectiveness of a specific program of exercises for strengthening the abductor muscles in these patients. Methods: A multicentre, prospective, randomised clinical trial was carried out in an outpatient rehabilitation setting on 103 patients given THR for DDH through a minimally-invasive anterolateral approach. Patients were randomly divided into a Study Group, including 46 patients, and a Control Group, including 57 patients. All patients underwent standard early postoperative rehabilitation. In addition, the Study Group were given an extra 2-week rehabilitation once full weight-bearing on the operated limb was allowed, aimed at strengthening the abductor muscles. All patients were evaluated preoperatively, and at about 3 and 6 months postoperatively. Clinical measures (lower limb-length differences, hip range of motion, abductor muscle strength), and functional measures (WOMAC, HHS, 10mt WT, SF-12) were taken. Results: Hip range of motion and functional outcome measures showed a progressive improvement at follow ups in both groups, significantly higher in the Study Group. In particular, abductor strength at 6 months post-op improved by 92.5% with respect to 35.7% in the Control Group. Conclusion: In addition to standard rehabilitation, a rehabilitation programme for strengthening the gluteal muscles in DDH patients who underwent THR determined an increase in muscle strength that improved functional performance and patient satisfaction.

Introduction: Articular surface replacement (ASR) XL implants exhibit higher-than-expected revision rates, blood ion concentrations and soft tissue lesions, making revisions troublesome and potentially unsatisfying. Appropriate techniques and outcomes in ASR XL revisions are rarely documented. The aims of this study were the assessments of pre-revision data, post-revision clinical and radiographic outcomes and ion levels in isolated acetabular ASR XL revisions performed using highly porous titanium cups and Delta ceramic articulations. Methods: 18 isolated acetabular ASR XL revisions in 16 patients were performed using Ti-Por cups (Adler Ortho, Milan, Italy) and Delta bearings (CeramTec, Plochingen, Germany). Pre-revision demographic, clinical, radiological and implant-related features were assessed. Clinical and radiographic parameters (cup positioning, osseointegration) after revisions were evaluated at a minimum follow-up of 5 years. Ion concentrations in blood and urine were collected in pre-revision setting and 1 year after revision. Results: 4 complications occurred in 3 different revisions (16.7%), 1 dislocation, 2 infections, 1 psoas impingement. No re-revision was performed at 5 years (1 scheduled arthroscopy). Good clinical outcomes were achieved (HHS score: 88.3 ± 9.2). All the cups showed reassuring signs of osseointegration (>3 parameters). Blood ion concentrations significantly decreased: patients with Co blood ion concentration over the threshold (7 μg/l) decreased from 76.5% to 0%. No pre-revision or intraoperative data influenced the revision outcomes. Conclusions: Highly porous titanium cups and Delta ceramic articulations provided reliable mid-term clinical and radiographic outcomes in isolated acetabular ASR XL revisions. Ion concentrations significantly decreased. Multicentre prospective controlled studies are required to confirm these preliminary outcomes.

Introduction: Aim of this study was to describe the clinical outcomes of 16 patients with iliopsoas (IP) impingement after primary total hip arthroplasty (THA), treated with an arthroscopic tendon release. Methods: 16 patients (11 females/5 males), with a mean age of 57.8 ± 11.1 years (age at THA: 54.4 ± 11 years) and a diagnosis of IP impingement after primary THA, were treated with the Wettstein tenotomy. Preoperatively, every patient underwent a diagnostic ultrasonography guided peritendinous injection and a computed tomography (CT) scan. Every patient was clinically evaluated using WOMAC score. Subjective pain relief and active hip flexion strength were measured. Results: No complications related to arthroscopy were detected. Every cup was prominent with a mean axial overhang of 13 ± 4.8 mm (range 5–20 mm). At a mean follow-up of 27 ± 20.1 months (range 6–48 months), the WOMAC score was 83.7 ± 10.1 points. 13 patients out of 16 (81.3%) had a complete pain relief. 14 patients out of 16 (88%) regained full active hip flexion strength at the final follow-up. 1 patient was scheduled for cup revision after 6 months, due to persistent symptomatology. No demographic data or CT measurements about cup position statistically influenced the outcome. Conclusions: When preceded by an appropriate diagnosis, arthroscopic tenotomy proved safe and effective for IP impingement, regardless the magnitude of cup protrusion.

BackgroundHip osteoarthritis (HOA) is the most common hip disorder and a major cause of disability in the adult population, with an estimated prevalence of end-stage disease and total hip replacement. Thus, the diagnosis, prevention, and treatment of the early stages of the disease in young adults are crucial to reduce the incidence of end-stage HOA.The purpose of this study was to determine whether (1) a relationship among the inflammatory status of labrum and synovium collected from patients with femoroacetabular impingement (FAI) would exist; and (2) to investigate the associations among the histopathological features of joint tissues, the pre-operative symptoms and the post-operative outcomes after arthroscopic surgery.MethodsJoint tissues from 21 patients undergoing hip arthroscopy for FAI were collected and their histological and immunohistochemical features were correlated with clinical parameters.ResultsSynovial mononuclear cell infiltration was observed in 25% of FAI patients, inversely correlated with the hip disability and osteoarthritis outcome score (HOOS) pain and function subscales and with the absolute and relative change in total HOOS. All the labral samples showed some pattern of degeneration and 67% of the samples showed calcium deposits. The total labral score was associated with increased CD68 positive cells in the synovium. The presence of labral calcifications, along with the chondral damage worsened the HOOS post-op symptoms (adjustedR-square = 0.76p= 0.0001).ConclusionsOur study reveals a relationship between the histologic labral features, the synovial inflammation, and the cartilage condition at the time of FAI.The presence of labral calcifications, along with the cartilage damage and the synovitis negatively affects the post-operative outcomes in patients with FAI.

Background: Periprosthetic hip infections (PHIs) are troublesome complications of hip arthroplasties. The gold standard procedure for treating chronic PHI is a 2-stage approach. Recently, however, more conservative approaches have been developed to spare the osseointegrated components and avoid sequestra, bone loss, devascularization, and difficult reconstructions. The partial two-stage approach, which leaves the well-fixed component in situ and removes the loosened component, may be an effective strategy. Objective: This paper, a narrative mini-review, analyzed the preliminary results of a partial 2-stage approach to treating chronic hip arthroplasty infections. Methods: Pertinent papers describing the partial 2-stage approach (leaving the well-fixed component in situ and removing the loosened component) were collected and evaluated. Results: Six main case series were selected. A total of 76 patients were included. Many patients were treated with socket removal and stem retention with quite similar surgical techniques. Many cases included highly virulent bacteria, and no pre-operative selection about comorbidities was performed. The first outcomes of this approach were promising, with a rate of infection control ranging from 81.3% to 100% at mid-term follow-up. Conclusion: This approach proved good at mid-term follow-up; however, many concerns still exist. In particular, the indications are imprecise, and the role of biofilm is still unclear. Despite the first good outcomes, the partial 2-stage approach for chronic PHI should be validated by multicenter prospective studies.

Background The incidence of total knee replacements (TKRs) in young patients is increasing. Few reports described encouraging results and acceptable survival rates. However, many concerns still persist, in particular about the high rates of infection and aseptic loosening. Aim of this article was to investigate the survival of TKRs in patients aged 45 years or younger in a registry population. Methods The Emilia-Romagna registry RIPO was enquired about TKRs in patients ≤45 years; 238 TKRs were evaluated at a mean follow-up of 5.4 years (range 0-15.6 years), examining the features of the patients involved, the survival rate, and the reasons for revision of the knee implants. Results The TKRs were generally performed in men, in private hospitals, and almost in half of the cases for other causes rather than primary osteoarthritis. The mean age was 40 years. Bicompartmental, cemented posterior-stabilized implants with fixed bearing were preferred. The survival rate was higher than 90% in the first 7 years, and then it decremented. The choice of implant did not apparently influence the survivorship. The final outcomes were acceptable, substantially in line with the previous literature about young patients. Twenty-one revisions occurred (8.8%), in particular 8 cases for aseptic loosening and 7 TKRs for infection. The rate of revision was higher than in overall population and even in some young cohorts. Conclusion TKRs in patients aged 45 years or younger seem a promising procedure, although the high rates of septic and aseptic loosening should be carefully evaluated. Prospective, well-designed studies are required to confirm and investigate these preliminary findings.

Background Fourth-generation ceramic-on-ceramic couplings were developed to improve ceramic toughness and strength. Encouraging outcomes in primary total hip arthroplasty were reported. This coupling was proposed as an attractive option even in the case of revision procedures, particularly in younger patients with a longer life expectancy. However, the pertinent literature is scarce. Thus, a registry study was conducted to investigate the midterm survival rates and reasons for re-revision of the fourth-generation ceramic-on-ceramic bearing surfaces in revision hip arthroplasties. Methods A total of 327 revision implants (all the components were exchanged) with BIOLOX Delta couplings were investigated using the regional orthopedic registry RIPO. The demographics, the survival rates, and the reasons for re-revision were assessed. Revisions with bearings other than Delta were compared. Results Delta bearings achieved a survival rate of 90.5% at 7 years, with stable results. Twenty-six (8%) re-revisions occurred at a mean follow-up of 4.1 years. And 2.8% of the re-revisions were due to recurrent dislocations; 1.5% of the cases were due to cup aseptic loosening. Septic loosening occurred in 1.6% of the cases. No ceramic fractures were reported. When compared to revisions with bearings other than Delta-on-Delta, Delta coupling cohort achieved similar performances at 5 and 7 years. Lower, nonsignificant rates of aseptic and septic loosening were reported in Delta cohort. Conclusion Delta-on-Delta couplings demonstrated to be reliable bearing surfaces in revision settings at a midterm follow-up. Clinical studies and longer follow-ups are required to investigate potential adverse effects, like squeaking and fractures, and confirm these preliminary findings. Level of Evidence Level III, therapeutic study.

Background Total hip arthroplasty (THA) in severe developmental dysplasia of the hip (DDH) is a challenging procedure. The most used techniques involve anatomic cup positioning, augmentation femoral osteotomy. However, anatomic cup positioning is not always feasible in severe DDH and osteotomy nonunion may ensue. The purpose of the study was to assess the survivorship, the hip score results, the radiological parameters (fixation, loosening, component position) of a large cohort of patients with Crowe III and IV DDH, treated with high hip center and modular necks THAs. Methods Eighty-four THAs in Crowe III and IV DDH were evaluated, achieving a final follow-up of 15.1 years. All the patients were treated with the same cementless implant (modular necks and ceramic-on-ceramic coupling) and the same approach (high cup placement with slight medialization). The patients were clinically evaluated (Harris Hip score and Merle d'Aubigne and Postel score). A radiographic evaluation was performed, analyzing the orientation of the cup. Results Eighty patients were available at the last follow-up. The clinical scores were good at the final follow-up. Two sciatic lesions occurred: one patient fully recovered. The overall survivorship was 90.5% at 15 years: only 2 cases of aseptic loosening were reported. The mean center of rotation height was 33 ± 8 mm and the medialization was 30 ± 5 mm. Conclusion A high cup placement with slight medialization is a valid technique in DDH patients. A good restoration of the offset, ceramic-on-ceramic coupling and a porous socket may provide durable results, overcoming the effects of increasing joint reaction forces related to high cup placement.

Total joint arthroplasty, one of the most successful orthopaedic procedures, predictably relieves pain and improves function for patients with a painful arthritic hip joint1. This high success rate has increased patient expectations, particularly those regarding hip function, after the surgery. To achieve better function and to reduce the implant dislocation rate, more attention has been given to the role of the restoration of femoral offset and soft-tissue balancing2,3. Surgeons today are committed to restoring the anatomy in each case independent of the patient's age or sex or the pathological condition of the hip. Anatomic studies of hip anatomy, specifically on the femoral side, have shown sex-based anatomic differences4-8. Women tend to have a shorter femoral neck, a thinner femoral shaft, a lower cervicodiaphyseal (CCD) angle, a lower femoral offset, and greater anteversion of the femoral neck (Fig. 1). These differences should be addressed during revision hip surgery in order to restore hip anatomy. In particular, to achieve proper soft-tissue balancing, the femoral offset should be accurately restored. The femoral offset is represented by the perpendicular distance from the center of the femoral head to the long axis of the femur (Fig. 2). McGrory et al.9 found a correlation between a lack of restoration of femoral offset and abductor muscle weakness and limping. These results depend on hip mechanics, with a fulcrum between body weight and the hip abductors (Fig. 3). The length of the lever arm of the hip abductors is smaller than that of body weight. Therefore, the abductors must generate a force that is larger than body weight to maintain a level pelvis. In contrast, an increase in femoral offset increases the lever arm of the abductors, reducing the force required to balance body weight and thereby …

The restoration of the hip centre of rotation in an anatomical position is considered to be relevant for total hip prosthesis survival. When the cup is implanted with a high centre of rotation, the lever arm of the abductor muscles is decreased, causing higher joint-reaction forces. Modular stems with varying lengths and geometries can be used to balance soft tissues, and ceramic bearing surfaces can be used to reduce the wear rate. Forty-four hip replacements performed with a high hip centre of rotation were matched with 44 performed with an anatomical centre of rotation. In all cases the preoperative diagnosis was dysplasia of the hip (DDH) and cementless modular neck prostheses with ceramic bearing surfaces were used. At nine years follow-up the mean Harris hip and WOMAC scores were not statistically different. All stems and cups were stable; the femoral offset was no different between the two groups (p = 0.4) as leg-length discrepancy (p = 0.25).

In osteoporotic patients cemented stems are usually used to achieve a good primary stability. However, when patients are obese or active the long-term survival of cemented prostheses is questioned. In these patients, a partially-cemented stem with a hybrid fixation could be advantageous. A hybrid stem was retrospectively evaluated at a minimum follow-up of 60 months (mean, 75 months) in 58 osteoporotic women: seventeen with a body mass index (BMI) >30 (obese), 41 with a BMI between 25 and 29.9 (overweight), and an UCLA score for activity level >6. At the latest follow up, the Harris hip score improved from 33.5 points preoperatively to 81.6 points, and the WOMAC score improved significantly. Three stems (4.9%) had an asymptomatic subsidence of less than 2.5 mm; no stem was revised. These results support the use of partially-cemented stems in heavy or active osteoporotic women.

We report two cases of bilateral cementless total hip arthroplasty in two young women affected by Morquio-Brailsford syndrome. Morquio-Brailsford disease belongs to the mucopolysaccharidoses; it shows growth retardation with disproportional dwarfism. Usually patients are affected by a severe joint degeneration from their 2nd or 3rd decade. Young age, severe dysplasia, and joint size are the main technical problems for a total hip replacement. Accurate radiographic and CT planning allows the use of standard prostheses instead of custom-made ones.

Revision of a total hip arthroplasty due to fracture of a ceramic component is rare. The fracture rate of ceramic components has been reported to be between 0.004%1 and 0.05%2 for femoral heads and between 0.013%2 and 1.1%3 for acetabular liners. Nevertheless, this problem is occurring more frequently because of the increasing use of ceramic total hip replacements. Revision arthroplasty performed because of a fractured ceramic component carries a high risk of failure: the fragments of the failed component are sharp and harder than metal; if left in the articular space, these fragments would act as an abrasive paste, and the use of a metal head against a polyethylene liner in the revision arthroplasty would quickly lead to catastrophic wear and failure of these new total hip implants4-6 (Fig. 1). Thus, revision arthroplasty performed because of a fractured ceramic component is difficult and the failure rate has been reported to be as high as 31%6. Fig. 1 Early failure of a revision arthroplasty performed because of fracture of a ceramic femoral head. The aims of the present study were to evaluate the outcome of revision total hip arthroplasty performed specifically to treat fracture of a ceramic component, to identify technical factors affecting the outcome, to propose some tips and tricks to make the process of revising a total hip arthroplasty for this reason easier, and to suggest guidelines for the treatment of a ceramic component fracture. From 1990 to 2009, 8022 primary ceramic hip prostheses were implanted at our institute; 3275 (40.8%) were in men and 4747 (59.2%) were in women. Additional patient demographic information is given in Table I. Kaplan-Meier curves with revision for ceramic fracture as the end point were computed to evaluate the rate of ceramic fracture. The analysis …

Background: Total hip replacement in patients with Legg-Calve-Perthes disease can be difficult because of the multiplanar deformities of the proximal part of the femur and previous surgery during childhood. The aim of the present study was to assess the long-term outcomes of total hip replacement in patients who had Legg-Calve-Perthes disease during childhood. Methods: A retrospective study was carried out to assess the results of thirty-two total hip replacements that had been performed for twenty-seven patients from January 1989 to November 2004. The average age at the time of surgery was 37.8 years. The average duration of follow-up was 124 months (range, fifty-eight to 248 months). All but one of the implants were cementless. Results: There was only one failure in the present study; specifically, the one cemented stem in the study failed two years after surgery. The cumulative survival rate at fifteen years was 96.9% (95% confidence interval, 90.8% to 100.0%). The overall rate of complications was 12.5%, with two permanent sciatic nerve palsies. At the time of the latest follow-up, the average Harris hip score was 87.5 (range, 73 to 96), which was a marked improvement in comparison with the preoperative score (average, 50.1; range, 25 to 75). Conclusions: Despite the high rate of neurological complications, possibly related to excessive limb lengthening or inadequate soft-tissue release, total hip replacement can be considered a feasible option for patients with Legg-Calve-Perthes disease. Careful preoperative planning is advisable in order to overcome the technical pitfalls related to the abnormal proximal femoral and acetabular anatomy of these patients. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Total hip replacement in developmental dysplasia of the hip is a demanding procedure and usually requires dedicated devices and special surgical techniques. Nevertheless, the described techniques have shown variable outcomes. The aim of this study was to assess the 11-year outcomes of an off-the-shelf modular neck prosthesis in dysplastic patients and to evaluate the ability of the modular neck system to adequately restore femoral offset, abductor muscles lever arm and leg length.We retrospectively evaluated 61 modular neck prostheses implanted in 47 patients between June 1995 and March 2004. The preoperative diagnosis was developmental dysplasia of the hip in all cases. The clinical outcomes were assessed using the Harris hip score and the Western Ontario and McMaster Universities score. The femoral offset, abductor muscles lever arm, height and medialization of the hip center of rotation, and differences in leg length were evaluated on postoperative radiographs. Prosthesis survival was calculated according to the Kaplan-Meier method considering any reason for revision as failure. The average follow-up was 117.2 months (range 57-162 months).The cumulative survival at 11 years was 97.5%. One prosthesis failed 5 years after surgery because of a ceramic liner fracture due to an inappropriate obstetric maneuver during labour. At the latest follow-up the mean Harris hip score was 74.7 (range 23-91). Leg length discrepancy was avoided in the majority of cases; femoral offset was almost always restored.The results of this series support the use of modular neck prostheses as an effective alternative in the treatment of developmental dysplasia of the hip. The modularity was very efficient in restoring offset, leg length and maintaining stability with a good mid-long-term follow-up. Unlike other proposed surgical techniques, these good results are achievable by a standard surgical technique and with an off-the-shelf prosthesis.

Total hip arthroplasty in the presence of acetabular non-union can be demanding. The irregular anatomy, the defect, and the presence of fibrous and necrotic tissue can hamper insertion of the acetabular component. We present a case of total hip arthroplasty in a patient with post-traumatic necrosis of the femoral head and non-union of the acetabulum and follow-up one year after the operation. Following accurate preoperative planning, removal of the pseudarthrosis material, and the use of the femoral head as an autograft, it was possible to insert the acetabular cup satisfactorily in a single-stage procedure.

The long-term successful outcomes of total hip replacement led to an extension of the surgical indications to young and active patients. To achieve a prompt functional recovery, varying surgical techniques have been proposed. In this study we present our anterolateral soft tissue sparing approach characterised by a lesser dissection of the muscles, a capsular repair and an accurate soft tissue tensioning and reconstruction. The target of this procedure is a full and quick restoration of hip function, reducing the rate of early complications such as hip dislocation.

In dwarfism hip arthritis, usually secondary to hip dysplasia, is a common finding at an early age. In these patients a joint replacement is a demanding procedure due to the peculiar joint deformity and the small size of the bones. We present a case of a bilateral hip replacement in a dwarf patient. In order to reduce intraoperative complications and improve the joint kinematics a thorough preoperative planning was performed by a CT based computerised system. On the basis of the planning we chose a conical shaped stem that enable as to restore limb length and offset with a low risk of femoral fracture. In conclusion, we consider total hip replacement in dwarfism a safe and effective procedure if an accurate preoperative planning is performed.

Brucella infection in arthroplasties is a rare event. An unspecific clinical symptomatology is associated with unclear radiographic peri-prosthetic signs of bone halisteresis. Only a positive anamnesis, combined with an antibiogram of the joint liquid and a high serum antibody titre, can lead to a definitive diagnosis. We report a case of Brucella melitensis infection in a total knee arthroplasty implanted 2 years earlier. With the absence of radiological signs of prosthetic loosening and thanks to a systemic antibiotic combined therapy (rifampicin + doxycycline) extended for 8 weeks, we were able to solve the infection avoiding surgery.

Ceramic prostheses have had some promising long term results [1], and modern metal-back alumina cups have shown very good clinical results [2,3,4]. Alumina has excellent tribological properties, a very high Young’s modulus that leads to very good compression strength, but it has poor bending strength: it has no way to deform [5]. This means that ceramic can break without warning. With modern ceramics, under normal physiologic conditions, the fatigue limit is never reached, therefore ceramic head fractures are seldom reported (0.004%10 in one study). On the contrary, ceramic liner fractures are not well recognized and their frequency could be underestimated. Besides, it is difficult to identify those patients at risk, because liner fractures can be related to multiple causes: dislocation, impingement, malpositioning, microseparation [6,7]. When a ceramic fracture involves the liner and is the consequence of repeated micro-trauma, the diagnosis is rarely made early, except when ceramic fragments are visible on X-ray. Moreover, revision surgery decision making after a failed ceramic-on-ceramic prosthesis is troublesome: the ceramic fragments which have spread into the periarticular space are abrasive, and they can lead to early failure of the revision procedure. In a multicenter study on 105 total hip revisions due to ceramic head fracture, Allain et al. reported a second revision rate of 31% (33 hips) at 5 years follow up. The main cause of the repeat revisions was aseptic loosening due to metal and polymethyl methacrylate wear [8].