We herein report a case of isolated hip pain in a four year old boy. The importance of this project is the unusual history, presentation, ultrasound, MRI and blood culture results and treatment, which lead to the diagnosis of adductor pyomyositis with a rare organism (Streptococcus Mitis) in a temperate country. The patient presented with a one day history of malaise, fever, left groin pain and inability to weight bear on the left leg. There was no history of any predisposing infections or recent travel. A working diagnosis of transient synovitis / septic arthritis of the hip was made on clinical examination. Plain radiograph and ultrasound of the hip was normal with no effusion. Two consecutive blood cultures suggested Streptococcus Mitis bacteriaemia and MRI scan confirmed pyomyositis of the left hip adductors that was too small to drain. Streptococcus Mitis is a normal commensal organism of the oral cavity however it can lead to opportunistic infections particularly endocarditis. Echocardiogram revealed no cardiac complications, in particular no endocarditic vegetation. Patient was treated with intravenous benzylpenicillin for a week followed by oral phenoxymethylpenicillin for a week. As it was a soft tissue infection, a short course of antibiotics was sufficient and he made a complete recovery. Adductor pyomyositis must be considered as a differential diagnosis in a child with unusual presentation of hip pain. When an ultrasound is normal, MRI scan is warranted to confirm diagnosis. Septic screen should include blood cultures. The commonest organisms are the Staphylococcus family. However if Streptococcus Mitis is isolated, cardiac sources of infection resulting in septic emboli must be investigated. Repeated MRI scans are required particularly if the patient does not respond to medical management

Aim. This study aims to determine the value of MRI in children with hip pain which remained unexplained following routine investigations including ultrasound examination. Materials and methods. Retrospective review of clinical notes and MRI findings in all children who received and MRI scan for undiagnosed hip pain over three years. Results. Fifty five children underwent an MRI scan of their hips for unexplained hip pain. 29 were male and 26 were female. The mean age was 10.9 years. The MR study provided a diagnosis in 22 children (40%), and was normal in 33 children (60%). Five cases were considered to be due to transient synovitis. Three children were diagnosed as osteoid osteoma. Two children were were found to have trochanteric bursitis. Two children were shown to have muscle trauma (one child with adductor trauma and one child with piriformis trauma). Two children were diagnosed with non-specific bone oedema. The remaining eight children were diagnosed with Perthes' disease, haemarthrosis, sacro-iliac infection, synovitis secondary to juvenile idiopathic arthritis, ischio-pubic osteochondrosis, acetabular dysplasia, Klippel-Trenaunay syndrome and resolution of an eosinophilic granuloma. None of the children discharged following a normal scan has subsequently presented with hip disease. Conclusions. It is concluded that MRI is useful in the diagnosis of hip pain in children in whom routine investigation has not yielded an answer

Abstract

To identify the differences in inflammatory profiles between hip OA, knee OA and non-OA control cohorts and investigate the association between cytokine expression and clinical outcome measurements, specifically pain.

A total of 250 individuals were recruited in three cohorts (100 knee OA, 50 hip OA, 100 control). Serum was collected and inflammatory profiles analysed using the Multiplex Human Cytokine Panel (Millipore) on the Luminex 100 platform (Luminex Corp., Austin, TX). The pain, physical function and activity limitations of hip OA cohort were scored using the WOMAC, SF-36, HHS and UCLA scores. All cytokine levels were compared between cohorts individually using Mann–Whitney–Wilcoxon (MWW) test with Bonferroni multiple comparison correction. Within hip OA cohorts, the effect of hip alignment (impingement and dysplasia) and radiographic grade (Kellgren and Lawrence grade, K/L grade) on cytokine levels were accessed by MWW test. Spearman's rank correlation test used to assess the association between cytokines and pain levels.

The three cohorts showed distinct inflammatory profiles. Specifically, EGF, FGF-2, MCP-3, MIP-1a, IL-8 were significant different between knee and hip OA; FGF-2, GRO, IL-8, MCP-1, VEGF were significant different between hip OA and control; Eotaxin, GRO, MCP-1, MIP-1b, VEGF were significant different between knee OA and control (p-value < 0.0012). For hip OA cohorts, cytokines do not differ between K/L grade three and K/L grade four or between patients that displayed either impingement or dysplasia. Three cytokines were significant associated with pain: IL-6 (p-value = 0.045), MDC (p-value = 0.032) and IP-10 (p-value = 0.038).

We have demonstrated that differences in serum inflammatory profiles exist between hip and knee OA patients. These differences suggest that OA may include different inflammatory subtypes according to affected joints. We also identified that the cytokine IL-6, MDC and IP-10 are associated with pain level in hip OA patients. These cytokines might help explain the inconsistent of presentation of pain with radiographical severity of OA joints. Future studies are needed to validate our findings and then to understand the following questions: (1) how differently affected joints are reflected in systematic biomarkers; (2) how these cytokines are biologically involved in the OA pain pathway.

Introduction

It is not uncommon to encounter patients with atypical hip or lower extremity pain, ill-defined clinico-radiological features and concomitant hip and lumbar spine arthritis. It has been hypothesized that an anaesthetic hip arthrogram can help identify the source of pain in these cases. The purpose of this study is to analyze our experience with this technique in order to verify its accuracy.

Over half of postpartum women experience pelvic ring or hip pain, with multiple anatomic locations involved. The sacroiliac joints, pubic symphysis, lumbar spine and pelvic girdle are all well documented pain generators. However, despite the prevalence of postpartum hip pain, there is a paucity of literature regarding underlying soft tissue intra-articular etiologies. The purpose of this systematic review is to document and assess the available evidence regarding underlying intra-articular soft tissue etiologies of peri- and postpartum hip pain. Three online databases (Embase, PubMed and Ovid [MEDLINE]) were searched from database inception until April 11, 2021. The inclusion criteria were English language studies, human studies, and those regarding symptomatic labral pathology in the peri- or postpartum period. Exclusion criteria were animal studies, commentaries, book chapters, review articles and technical studies. All titles, relevant abstracts and full-text articles were screened by two reviewers independently. Descriptive characteristics including the study design, sample size, sex ratio, mean age, clinical and radiographic findings, pathology, subsequent management and outcomes were documented. The methodological quality of the included studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS) instrument. The initial search identified 2472 studies. A systemic screening and assessment of eligibility identified 5 articles that satisfied the inclusion criteria. Twenty-two females were included. Twenty patients presented with labral pathology that necessitated hip arthroscopy with labral debridement or repair with or without acetabuloplasty and/or femoroplasty. One patient presented with an incidental labral tear in the context of osteitis condensans illi. One patient presented with post-traumatic osteoarthritis necessitating a hip replacement. The mean MINORS score of these 5 non-comparative studies was 2.8 (range 0-7) demonstrating a very low quality of evidence. The contribution of intra-articular soft tissue injury is a documented, albeit sparse, etiology contributing to peri- and postpartum hip pain. Further research to better delineate the prevalence, mechanism of injury, natural history and management options for women suffering from these pathologies at an already challenging time is necessary to advance the care of these patients

Introduction. Transfemoral osseointegration (TFOI) for amputees has substantial literature proving superior quality of life and mobility versus a socketed prosthesis. Some amputees have hip arthritis that would be relieved by a total hip replacement (THR). No other group has reported performing a THR in association with TFOI (THR+TFOI). We report the outcomes of eight patients who had THR+TFOI, followed for an average 5.2 years. Materials & Methods. Our osseointegration registry was retrospectively reviewed to identify all patients who had TFOI and also had THR, performed at least two years prior. Six patients had TFOI then THR, one simultaneous, one THR then TFOI. All constructs were in continuity from hip to prosthetic limb. Outcomes were: complications prompting surgical intervention, and changes in subjective hip pain, K-level, daily prosthesis wear hours, Questionnaire for Persons with a Transfemoral Amputation (QTFA), and Short Form 36 (SF36). All patients had clinical follow-up, but one patient did not have complete mobility and quality of life survey data at both time periods. Results. Four (50%) were male, average age 52.7±14.8 years. Three patients (38%) had amputation for trauma, three for osteosarcoma, one each (13%) infected total knee and persistent infection after deformity surgery. One patient died one year after THR+TOFA from subsequently diagnosed pancreatic cancer. One patient had superficial debridement for infection with implant retention after five years. No implants were removed, no fractures occurred. All patients reported severe hip pain preoperatively versus full relief of hip pain afterwards. K-level improved from 0/8=0% K>2 (six were wheelchair-bound) to 5/8=63% (p=.026). At least 8 hours of prosthesis wear was reported by 2/7=29% before TOFA vs 5/7=71% after (p=.286). The QTFA improved in all categories, but not significantly: Global (40.0±21.6 vs 60.0±10.9, p=.136), Problem (50.2±33.2 vs 15.4±8.4, p=.079), and Mobility (35.9±26.8 vs 58.3±30.7, p=.150). The SF36 also improved minimally and not significantly: Mental (53.6±12.0 vs 54.7±4.6, p=.849) and Physical (32.5±10.9 vs 36.3±11.2, p=.634). Conclusions. THR+TFOI is a successful reconstruction option for amputees who desire relief from severe pain related to hip joint degeneration, and also the opportunity for improved mobility and quality of life that TFOI typically confers. In our cohort, the procedure proved safe: no associated deaths, no removals, one soft tissue debridement. Mobility improved markedly. Quality of life improved, but not to significant thresholds as measured by the surveys. THR+TFOI appears safe and reasonable to offer to transfemoral amputees with painful hip joint degeneration

Rapidly progressive osteoarthritis of the hip (RPOH) is an unusual subset of osteoarthritis. It is characterized by rapid joint space loss, chondroly­sis, and sometimes marked femoral head and acetabular destruction as a late finding. The exact pathogenetic mechanism is unknown. Potential causes of RPOH include subchondral insufficiency fracture resulting from osteoporosis, increasing posterior pelvic tilt as a mechanical factor, and high serum levels of matrix metalloproteinase (MMP)-3 as biological factors. This study was aimed to identify some markers that associate with the destructive process of RPOH by analyzing the proposed pathological factors of the disease, MMP-3, pelvic tilt, and osteoporosis. Of female patients who visited our hospital with hip pain from 2012 through 2018, this study enrolled female patients with sufficient clinical records including the onset of hip pain, age and body mass index (BMI) at the onset, a series of radiographs during the period of >12 months from the onset of hip pain, and hematological data of MMP-3 and C-reactive protein (CRP). We found the hip joints of 31 patients meet the diagnostic criteria of RPOH, chondrolysis >two mm in one year, or 50% joint space narrowing in one year. Those patients were classified into two groups, 17 and 14 patients with and without subsequent femoral head destruction in one year shown by computed tomography, respectively. Serum MMP-3 and CRP were measured with blood samples within one year after the hip pain onset. The cortical thickness index (CTI) as an indicator of osteoporosis and pelvic tilt parameters were evaluated on the initial anteroposterior radiograph of the hip. These factors were statistically compared between the two groups. This study excluded male patients because RPOH occurs mainly in elderly females and the reference intervals of MMP-3 are different between males and females. There was no difference in age at onset or bone mass index between the RPOH patients with and without subsequent femoral head destruction. Serum levels of MMP-3 were significantly higher in the RPOH patients with the destruction (152.1 ± 108.9 ng/ml) than those without the destruction (66.8 ± 27.9 ng/ml) (P = 0.005 by Mann-Whitney test). We also found increased CRP in the patients with femoral head destruction (0.725 ± 1.44 mg/dl) compared with those without the destruction (0.178 ± 0.187 mg/dl) (P = 0.032 by Mann-Whitney test). No difference in the duration between the hip pain onset and the blood examination was found between the two groups. There was no significant difference in CTI or pelvic tilt between the two groups. The pathological condition that may increase serum MMP-3 and CRP could be involved in femoral head destruction after chondrolysis of the hip in patients with RPOH

Complete or nearly complete disruption of the attachment of the gluteus is seen in 10–20% of cases at the time of THA. Special attention is needed to identify the lesion at the time of surgery because the avulsion often is visible only after a thickened hypertrophic trochanteric bursa is removed. From 1/1/09 to 12/31/13, 525 primary hip replacements were performed by a single surgeon. After all total hip components were implanted, the greater trochanteric bursa was removed, and the gluteus medius and minimus attachments to the greater trochanter were visualised and palpated. Ninety-five hips (95 patients) were found to have damage to the muscle attachments to bone. Fifty-four hips had mild damage consisting of splits in the tendon, but no frank avulsion of abductor tendon from their bone attachments. None of these cases had severe atrophy of the abductor muscles, but all had partial fatty infiltration. All hips with this mild lesion had repair of the tendons with #5 Ticron sutures to repair the tendon bundles together, and drill holes through bone to anchor the repair to the greater trochanter. Forty-one hips had severe damage with complete or nearly complete avulsion of the gluteus medius and minimus muscles from their attachments to the greater trochanter. Thirty-five of these hips had partial fatty infiltration of the abductor muscles, but all responded to electrical stimulation. The surface of the greater trochanter was denuded of soft tissue with a rongeur, the muscles were repaired with five-seven #5 Ticron mattress sutures passed through drill holes in the greater trochanter, and a gluteus maximus flap was transferred to the posterior third of the greater trochanter and sutured under the vastus lateralis. Six hips had complete detachment of the gluteus medius and minimus muscles, severe atrophy of the muscles, and poor response of the muscles to electrical stimulation. The gluteus medius and minimus muscles were sutured to the greater trochanter, and gluteus maximus flap was transferred as in the group with functioning gluteus medius and minimus muscles. Postoperatively, patients were instructed to protect the hip for 8 weeks, then abductor exercises were started. The normal hips all had negative Trendelenburg tests at 2 and 5 years postoperative with mild lateral hip pain reported by 11 patients at 2 years, and 12 patients at 5 years. In the group of 54 with mild abductor tendon damage that were treated with simple repair, positive Trendelenburg test was found in 5 hips at 2 years and in 8 hips at 5 years. Lateral hip pain was reported in 7 hips at 2 years, and in 22 at 5 years. In the group of 35 hips with severe avulsion but good muscle tissue, who underwent repair with gluteus maximus flap transfer, all had good abduction against gravity and negative Trendelenburg tests at 2 and 5 years postoperative, and none had lateral hip pain. Of the 6 hips with complete avulsion and poor muscle who underwent abductor muscle repair and gluteus maximus flap transfer, all had weak abduction against gravity, mildly positive Trendelenburg sign, and mild lateral hip pain at 2 and 5 years postoperative. Abductor avulsion is uncommon but not rare, and is detected during THA only by direct examination of the tendon and removal of the trochanteric bursa. Simple repair of mild abductor tendon damage did not prevent progressive abductor weakness in some hips; and the increase in number of patients with lateral hip pain from 2 to 5 years suggests progressive deterioration. Augmentation of the repair with a gluteus maximus flap appears to provide a stable reconstruction of the abductor muscles, and seemed to restore abductor function in the hips with functioning muscles

The purpose of this study was to assess the knowledge acquired from completing online case-based e-learning modules. A secondary objective was to identify how students use these independent resources and gauge their level of support for this novel instructional strategy. Fourth year medical students were randomized to either a module or control group. Both groups received the standard musculoskeletal medical school curriculum, while the students in the module group were also given access to case-based online modules created to illustrate and teach important orthopaedic concepts related to unique clinical presentations. The first module depicted an athlete with an acute knee dislocation while the second module portrayed a patient with hip pain secondary to femoral acetabular impingement (FAI). All participating students completed a knowledge quiz designed to evaluate the material presented in the module topics, as well as general musculoskeletal concepts taught in the standard curriculum. Following the quiz, the students were invited to share their thoughts on the learning process in a focus- group setting, as well as an individual survey. Demographic data was also collected to gauge student's exposure to and interest in orthopaedics, emergency medicine, anatomy and any prior relevant experience outside of medicine. Twenty-five fourth year medical students participated in the study with 12 randomized to the module group and 13 to the control group. The regression revealed students in the module group did on average 18.5 and 31.4 percentage points better on the knee and hip quizzes respectively, compared to the control group, which were both significant with a p-value < 0.01. Additionally, students who had completed an orthopaedics elective did 20 percentage points better than those who had not, while there was no significant improvement in students who had just completed their core orthopaedics rotation. The feedback collected from the survey and small group discussion was positive with students wishing more modules were available prior to musculoskeletal clinical skills sessions and their orthopaedics rotations. Medical students given access to online case-based e-learning modules enjoyed the innovative teaching strategy and performed significantly better on knowledge quizzes than their classmates who only received the standard musculoskeletal curriculum

Femoroacetabular impingement (FAI) deformities are a potential precursor to hip osteoarthritis and an important contributor to non-arthritic hip pain. Some hips with FAI deformities develop symptoms of pain in the hip and groin that are primarily position related. The reason for pain generation in these hips is unclear. Understanding potential impingement mechanisms in FAI hips will help us understand pain generation. Impingement between the femoral head-neck contour and acetabular rim has been proposed as a pathomechanism in FAI hips. This proposed pathomechanism has not been quantified with direct measurements in physiological postures. Research question: Is femoroacetabular clearance different in symptomatic FAI hips compared to asymptomatic FAI and control hips in sitting flexion, adduction, and internal rotation (FADIR) and squatting postures?. We recruited 33 participants: 9 with symptomatic FAI, 13 with asymptomatic FAI, and 11 controls from the Investigation of Mobility, Physical Activity, and Knowledge Translation in Hip Pain (IMAKT-HIP) cohort. We scanned each participant's study hip in sitting FADIR and squatting postures using an upright open MRI scanner (MROpen, Paramed, Genoa, Italy). We quantified femoroacetabular clearance in sitting FADIR and squatting using beta angle measurements which have been shown to be a reliable surrogate for acetabular rim pressures. We chose sitting FADIR and squatting because they represent, respectively, passive and active maneuvers that involve high flexion combined with internal/external rotation and adduction/abduction, which are thought to provoke impingement. In the squatting posture, the symptomatic FAI group had a significantly smaller minimum beta angle (−4.6º±15.2º) than the asymptomatic FAI (12.5º ±13.2º) (P= 0.018) and control groups (19.8º ±8.6º) (P=0.001). In the sitting FADIR posture, both symptomatic and asymptomatic FAI groups had significantly smaller beta angles (−9.3º ±14º [P=0.010] and −3.9º ±9.7º [P=0.028], respectively) than the control group (5.7º ±5.7º). Our results show loss of clearance between the femoral head-neck contour and acetabular rim (negative beta angle) occurred in symptomatic FAI hips in sitting FADIR and squatting. We did not observe loss of clearance in the asymptomatic FAI group for squatting, while we did observe loss of clearance for this group in sitting FADIR. These differences may be due to accommodation mechanisms in the active, squatting posture that are not present in the passive, sitting FADIR posture. Our results support the hypothesis that impingement between the femoral head-neck contour and acetabular rim is a pathomechanism in FAI hips leading to pain generation

Femoroacetabular impingement (FAI) is a condition of the hip where there is a mismatch of the femoral head and hip acetabulum. This mismatch creates abnormal contact between the bones and causes hip pain which can lead to damage, and eventually osteoarthritis of the hip. The diagnosis and treatment of FAI has become one of the most popular clinical scenarios in orthopaedic surgery, with hip arthroscopy procedures increasing exponentially over the past five years. Surgical intervention usually involves correcting the existing deformities by reshaping the ball and socket (“osteoplasty” or “rim trimming”) so that they fit together more easily while repairing any other existing soft tissue damage in the hip joint (e.g. labral repair). Although correction of the misshaped bony anatomy and associated intra-articular soft tissue damage of the hip is thought to appease impingement and improve pain and function, the current evidence is based on small, observational, and low quality studies. A lack of definitive evidence regarding the efficacy of osteochondroplasty in treating FAI fueled the design and execution of the FIRST randomized controlled trial (RCT). FIRST evaluated the impact of surgical correction of the hip impingement morphology with arthroscopic osteochondroplasty versus arthroscopic lavage on pain, function, and quality of life in adults aged 18–50 years diagnosed with non-arthritic FAI at one year. FIRST was a large definitive RCT (NCT01623843) enrolling patients with FAI requiring surgical intervention across 11 international clinical sites. Participants were randomized to either arthroscopic osteochondroplasty (shaving of bone) or lavage (washing the joint of painful inflammation debris). The primary outcome was patient-reported pain within one year of the initial surgery measured using the Visual Analogue Scale (VAS). Secondary outcomes included function, health utility, and health-related quality of life using several general and hip-centric health questionnaires. An independent, blinded adjudication committee evaluated the quality of surgery, re-operations, and other patient complications. Patients and data analysts were blinded to the treatment groups. Two-hundred and twenty participants were enrolled into the FIRST trial over a six-year period (pilot phase: N=50, from 2012–2013 and definitive phase: N=170, from 2015–2018) at 11 clinical sites in Canada, Finland, and Denmark. The FIRST results will be released at the ISAKOS annual meeting as follows. The absolute difference in rate of pain reduction between groups was XX (95% CI: YY-YY, p=X). The mean differences of the Short-Form 12 (SF-12, MCS and PCS), Hip Outcome Score (HOS), International Hip Outcome Tool (iHOT-12), and EuroQol 5-Dimensions (EQ-5D) between groups are XX (95% CI: YY-YY, p=X)…, respectively. Reoperations occurred in XX of 220 (X%) patients over the one-year follow up period (OR:XX, 95% CI: YY-YY, p=X) and the patients treated with arthroscopic osteochondroplasty conferred the following risk of reoperation within one-year compared to arthroscopic lavage (RR:XX, 95% CI: YY-YY, p=X). This RCT represents major international efforts to definitively identify the optimal treatment strategy for FAI. The results of this trial will change practice, being used to prevent chronic hip pain and loss of function caused by hip osteoarthritis

Introduction. Subtle deformities of the acetabulum and proximal femur are recognised as biomechanical risk factors for the development of hip osteoarthritis (OA) as well as a cause of hip and groin pain. We undertook this study to examine relationships between a number of morphological measurements of the acetabulum and proximal femur and the hip pain in a 20-year longitudinal study. Methods. In 1989 women of 45–64 years of age were recruited. Each had an AP-Pelvis radiograph at Year-2. These radiographs were analysed using a validated programme for measuring morphology. All morphological measurements were read blinded to outcome. At year 3 all participants were asked whether they experienced hip pain (side specific). This was repeated at visits up to and including 20-years. Logistic regression analysis (with robust standard errors and clustering by subject identifier) was performed using hip pain as a binary outcome. The model adjusted for baseline age, BMI and joint space and included only participants who were pain free on initial questioning. Results. 743 participants were included in the analysis. Median age 74.0. Pain was reported in 14.2% of hips. Logistic regression analyses revealed that extrusion index and LCE were significantly associated with hip pain before and after adjusting for covariates (OR 4.88[95%CI 1.32–17.97, p=0.017] and 0.84[95%CI 0.74–0.96, p=0.012] respectively). Modified triangular index height (MTIH) was also significantly associated after adjusting for covariates (OR 1.10[95%CI 1.01–1.20, p=0.022]). Extrusion index and MTIH were independently associated with hip pain at 20-years when used in the same model. No significant interaction was identified. Conclusions. This study provides evidence that measurements of hip morphology characteristic of previously undiagnosed dysplasia and FAI are predictive of hip pain in a 20-year longitudinal study. MTIH, LCE and Extrusion index were significant predictors of pain. This is the first study to describe these associations between hip morphology and pain in a longitudinal cohort

Abductor deficiency after THA can result from proximal femoral bone loss, trochanteric avulsion, muscle destruction associated with infection, pseudotumor, ALTR to metal debris, or other causes. Constrained acetabular components are indicated to control instability after THA with deficient abductors. However, the added implant constraint also results in greater stresses at the modular liner-locking mechanism of the constrained component and bone-implant fixation interface, which can contribute to mechanical failure of the constrained implant or mechanical loosening. Use of large heads has been effective in reducing the rate of dislocation after primary THA. However, relatively large (36mm) heads were not found to be effective in controlling dislocation in patients with abductor deficiency. Dual mobility implants which can provide considerably larger head diameters than 36mm may offer an advantage in improving stability in patients with abductor deficiency. However the utility of these devices in controlling instability after THA with deficient abductors has not been established. Whiteside has described a transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter for treatment of absent abductors after THA. Transposition of the tensor muscle requires raising an anterior soft tissue flap to the lever of the interval between the tensor muscle and sartorius, which is the same interval used in an anterior approach to the hip. The muscle is transected distally and transposed posteriorly to attach to the proximal femur. This can result in soft tissue redundancy between the posterior tensor muscle and anterior gluteus maximus. This interval is separated and the anterior gluteus maximus also attached to the proximal femur. The transposed tensor muscle provides muscle coverage over the greater trochanter, which may be beneficial in controlling lateral hip pain. In our practice, 11 patients were treated with Whiteside's tensor muscle transfer. Six patients had absent abductors, one had an avulsed greater trochanter, and four intact but weak abductors. One patient had a muscle transposition alone, one had an ORIF of the greater trochanter and muscle transposition, two had a muscle transposition and head/liner exchange, three had a muscle transposition and cup revision, two had a femoral revision and liner exchange with muscle transposition, and two had a muscle transposition with both component revision. None of the patients had constrained components. The mean pre-operative abductor strength was 2.2 (0/5 in four patients 3/5 in four patients, and 4/5 in three patients). Pre-operative lateral hip pain was none or mild in two patients, moderate in three, and severe in six patients. Mean post-operative abductor strength was 3.2 (2/5 in four patients, 3/5 in three, 4/5 in two, 5/5 in two patients). Post-operative lateral hip pain was none in five and mild in six patients. One patient sustained a dislocation four weeks after surgery which was treated with open reduction. All of the other hips have remained stable. Treatment of patients with hip instability and abductor deficiency has generally required use of a constrained acetabular component. In our experience, transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter can improve abductor strength by one grade and also reduce lateral hip pain. The combination of a large head and tensor muscle transposition may be a viable alternative to use of a fully constrained component in patients with deficient abductors after THA. However, the need for implant constraint should also be individualised and based on factors such as the viability of the transposed muscle, patient compliance with post-operative activity restrictions, femoral head/neck ratio, and cup position

Introduction. Torsional deformities are increasingly recognized as an additional factor in young patients with hip pain resulting from pincer- and cam-deformities. For example decreased femoral torsion can worsen an anterior Femoroacetabular impingement (FAI) conflict while an increased torsion can be beneficial with the same configuration. It is unknown how often torsional deformities are present in young patients presenting with hip pain that are eligible for joint preserving surgery. We questioned (1) what is the prevalence of a pathological femoral torsion in hips with FAI or hip dysplasia? (2) which hip disorders are associated with an abnormal torsion?. Methods. An IRB-approved retrospective study of 463 consecutive symptomatic FAI patients (538 hips) and a MRI or CT scan on which femoral torsion could be measured was performed (‘study group'). Out of 915 MRI we excluded 377 hips. The study group was divided into 11 groups: Dysplasia (< 22° LCE), retroversion, anteverted hips, overcoverage (LCE angle 36–39°), severe overcoverage (LCE>39°), cam (>50° alpha angle), mixed FAI, varus- (<125° CCD angle), valgus- (>139° CCD), Perthes-hips and hips with no obvious pathology. The ‘control group' of normal hips consisted of 35 patients (35 hips) without radiographic signs of osteoarthritis or hip pain wich was used for a previous study. Femoral antetorsion was measured according to Tönnis et al. as the angle between the axis of the femoral neck and the posterior axis of the femoral condyles. Normal femoral torsion was defined by Tönnis et al. as angles 10–25° while decreased resp. increased torsion was defined as <5° and >25°. Statistical analysis was performed using analysis of variances (ANOVA). Results. (1) Fifty-one percent of the patients of the study group presented with abnormal values for femoral torsion. Torsional deformities (<10° or >25°) were measured in 52% of all 538 hips eligible for joint preserving surgery. (2) Torsional deformities were present in 86% of Perthes hips, in 61 % of dysplastic hips, 52.3 % of hips with overcoverage, in 51% of mixed FAI, in 50% of varus hips, in 45% of valgus hips, in 45% of retroverted hips, in 47% of anteverted hips, in 43% of cam FAI, 35% of hips with severe overcoverage. No torsional deformity was present in the control group. Analysis of Variances (ANOVA) revealed significant differences (p<0.001) of torsion between normal hips (mean 17°) and hips with dysplasia (26°), valgus hips (27°), hips with no obvious pathology (30°) and Perthes hips (32°). Mean femoral torsion was in the normal range in the other groups. Conclusion. More than half of the patients wich are eligible for joint preserving surgery of the hip present with abnormal femoral torsion. In particular dysplastic-, valgus-, Perthes hips and hips with no obvious pathology had a significantly altered femoral torsion compared to normal hips. Femoral antetorsion should be measured in every patient eligible for hip-preserving surgery

Introduction. To evaluate the clinical success and hip pain and function of patients with infected hip replacement treated by two-stage exchange using a temporary implant with high dose vancomycin added to the antibiotic cement at the first stage revision. Method. Thirty-three hips in 32 patients (median 67 yrs) underwent first stage revision using the PROSTALAC™ system (n=27) or a self-made system using an Elite long stem (n=6). Infection was diagnosed after 19 primary, 11 revision and 3 hemiarthroplasty hip replacements. Patients were reviewed regularly clinically and by questionnaire. The median follow-up was 3 years. Results. Five hips (15%) had repeat first stage for persistent infection. Twenty-four hips (73%) progressed to second stage. Five hips (15%) did not progress to second stage. Four hips (12%) underwent excision arthroplasty. There was a further one recurrence of infection (4%) requiring repeat two stage revision at 3 years. Patients reported, on average, minimal to no hip pain after second stage. The median Harris Hip Score (HHS) after first stage was 59, and at 2 years after second stage was 75. For comparison, the 2 year HHS in our patients that had undergone standard cemented femoral revision was 75. Conclusion. A temporary hip implant with high-dose vancomycin cement has improved our clinical management of infected hip replacement after the second stage THR. Patients report hip pain and function that compares to that achieved for standard revision hip replacement

We report a case of fatal heart failure caused by cobalt intoxication after revision THR in the patient who successfully underwent re-revision THR. 53-year old male presented to emergency room in our hospital with progressive shortness of breath. Symptom was started about 6 months ago so he visited local hospital. He worked up for worsening dyspnea. Simple chest radiograph and enhanced heart MRI study were performed and they showed bilateral pericardial and pleural effusion. There was no evidence of ischemic change. Transthoracic echocardiogram showed the evidence of heart failure, left ventricular ejection fraction(EF) was 40%. He was admitted at local hospital and started on vasopressors but urine output was decreased and follow-up echocardiogram showed a 25% of EF. Patient recommended heart transplantation and transferred our hospital emergency room. He underwent sequential bilateral total hip arthroplasties using CoP bearing surfaces. At 12 years postoperatively, he presented to the other hospital with acute onset of left hip pain. He was diagnosed ceramic head fracture on his left hip. Head and liner change revision surgery was performed using Cobalt-Chrome alloy 28mm metal head and Protruded cross-linked polyethylene liners. In our hospital, the patient admitted cardiovascular department of internal medicine. Patient complained nonspecific fatigue and general weakness but had no other symptoms such as visual and hearing loss, cognitive dysfuction. During work-up, patient presented progressive left hip pain and complaint of discomfort for the mass on the left groin. He also complained Left leg weakness and numbness. Simple radiograph and enhanced CT study was done. Simple radiograph image shows radiodense area around the hip joint and radiologist suspected heterotopic ossification. The cardiovascular department consulted orthopedic department. In the image findings showed huge mass combined hemorrhagic component lining acetabular component extending psoas compartment and eccentric wear on cobalt-chrome alloy metal head. Also highly radiodense material was seen around neck inferor portion and severly deformed metal head was seen. It was highly suspected that metal related granuloma, which means severe metallosis. Performed heavy metals screen, cobalt levels were 397,800 μg/Land chrome levels were 236,000 μg/L suggesting cobalt toxicity. Hip joint aspiration was done for decompression as radiologic intervention and EDTA (ethylenediamine tetraacetate) chelation therapy started immediately. After 10 cycle chelating therapy, metal level was lowered cobalt levels by 255.2μg/L and chrome levels by 39.5 μg/L. When hospital day after 134, Medical condition of the patient was getting improved, we underwent revision surgery using ceramic on ceramic bearing surface. The patient discharged postoperative 79 days. Final heavy metals screen results were 27.79μg/L on cobalt and 22.17μg/L on chrome. Although there were also reported a good clinical result of revision surgery using MoP bearing, and some surgeons reluctant to use CoC articulation because of concerns about re-fracture of ceramic. But take into account like this devastating complication after cobalt-chrome wear caused by remained ceramic particles, we should carefully select which bearing is safer

Background. Previous studies have indicated poor outcomes and high complication rate in patients having revision of metal-on-metal (MoM) hip implants resulting from adverse local tissue reactions. Metal ions released by MoM bearings may potentially increase infection occurrence in patients with failed implants. Questions/purposes. We reviewed all patients at our institution who sustained revision of a failed large-head metal-on-metal hip implant to determine if infection-related complications are associated with the elevation of serum metal ions concentration. Methods. From December 2005 to April 2013, we performed 44 revisions of large-head MoM total hip arthroplasty (THA) and resurfacing in 44 patients. In all revision procedures MoM couplings (ASR XL Acetabular System and DePuy ASR Hip Resurfacing System) were explanted. Preoperative diagnosis were: aseptic loosening in 21 hips, hip pain with high serum metal ions levels in 7 hips, high serum metal ions levels without hip pain in 9 hips, deep infections in 4 hips, unexplained hip pain in 2 hips and periprosthetic fracture in 1 hip. Serum cobalt and chromium analysis were preoperatively conducted in 25 patients. Intraoperative fluid aspiration was performed in all cases to determine the presence or absence of periprosthetic joint infection. Results. Fluid analysis for bacteria reported that 35 of 45 cases were culture negative and 10 of 45 cases (22%) were culture positive to Staphylococcus (St) Aureus (4), St Capitis (2), St Epidermidis (2), St Hominis (1), Streptococcus Mitis (1). All preoperative diagnoses of deep infection were confirmed. Within patients evaluated with serum metal ions analysis (mean Co and Cr, 78 μg/l and 39 μg/l, respectively), five cultures resulted positive (20%). The infection rate within patients with higher (> 20 μg/l) metal ions levels (4 positive cultures of 18, 22%) was not significantly higher than infection rate within patients with lower (≤ 20 μg/l) metal ions levels (1 positive culture of 7, 14%). Conclusions. We observed a high rate of periprosthetic joint infection among our revision cases. High metal ions concentrations released by MoM bearings might promote bacterial infections in patients with MoM THA and resurfacing. When evaluating patients with failed MoM hip devices, there may be an increased incidence of co-infection in these patients

There have been numerous reports regarding “pseudotumor” associated with hip arthroplasty. We present two reports in which main etiology in the pseudotumor formation was titanium (Ti), but not cobalt-chromium (Co-Cr). We should keep in mind that Ti analysis is essential in some cases. (Case 1) A 68-year-old male presented to our institution because of right hip pain and lower extremity swelling four years after a bipolar hemiarthroplasty. MRI predicted a cystic pseudotumor. However, revision surgical findings showed no apparent cause of ARMD previously described in the literatures. Postoperative analysis showed that the metal debris mainly originated from the Ti alloy itself. (Case reports in Orthopedics, vol.2014, Article ID 209461, 4 pages). (Case 2) A 77-year-old female presented to our institution because of right hip pain and swelling six years after a total hip arthroplasty using a cable trochanteric reattchment. Plain radiographs demonstrated evidences of severe osteolysis and multiple fragments of the broken cable. However, MRI predicted a psudotumor(See Figure 1). Postoperative analysis clarified that main etiology in the pseudotumor formation was the stem mede of Ti, but not the cable made of Co-Cr

The aim of this study was to assess the incidence of low-grade infections in total hip arthroplasty revisions and the clinical outcomes after two-time revision surgery. Retrospective study of total hip arthroplasty revision surgery between January of 2012 and December of 2013. Inclusion criteria: two-time revision surgery, PCR (pre and post-op) white blood cells count and microbiological culture. The diagnosis of low-grade infection was based on the Academy of Orthopedic Surgeons’ (AAOS) guidelines. All patients were evaluated with the Harris Hip Score (HHS). Between this period were revised a total of 79 hips, none of them bilateral, of these fourteen full-filled the inclusion criteria, eight women and six men. The mean time between primary arthroplasty and revision surgery was 4.5 years. The interface was metal-on-polyethilene in thirteen and metal-on-metal in one. All patients had at least three episodes at the urgency department with permanent hip pain in the last six months. Ten have done a course of antibiotics previous to surgery. Intra-articular pus was present in four patients. The agent isolated was S. Aureus in five and S. Epidermidis in two. An elevated PCR and leucocytosis was present in all patients. The mean PCR was 18.1 and leucocytes countage 7600. The HHS was good in four patients, fair in seven patients and poor in three. These three patients with poor had another surgical intervention due to recurrent dislocation. Periprosthetic joint infection is a common complication after total hip arthroplasty (THA). The incidence is approximately 1% after primary replacement and about 4% revision arthroplasty. As stated by Hanssen successful treatment outcomes require precise assessment of the infecting organism, the immune status of the patient, and the condition of the bone and soft tissues around the joint. With this study we tried to establish a protocol in our service: patient with a THA, interface metal-on-polyethilene, persistent coxalgia and elevated PCR will be diagnosed with low-grade infection, however we need further revision of our experience