Pain following total hip arthroplasty is a relatively rare event. Several series place the incidence of some degree of pain post THA at approximately 5%.

A systematic approach to determining etiology will direct treatment. Hip pain can be categorised as:

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

Patients with painful metal-on-metal bearings presenting to the orthopaedic surgeon are a difficult diagnostic challenge. The surgeon must go back to basic principles, perform a complete history and physical exam, obtain serial radiographs and basic blood work (ESR, CRP) to rule out common causes of pain and determine if the pain is, or is not, related to the bearing. The Asymptomatic MoM Arthroplasty: Patients will present for either routine follow up, or because of concerns re: their bearing. It is important to emphasise that at this point the vast majority of patients with a MoM bearing are indeed asymptomatic and their bearings are performing well. The surgeon must take into account: a) which specific implant are they dealing with and what is its track record; b) what is the cup position; c) when to perform metal ion testing; d) when to perform further soft tissue imaging (MARS MRI, Ultrasound); e) when to discuss possible surgery. Painful MoM THA causes not related to the bearing couple: These can be broken down into two broad categories. Causes that are Extrinsic to the hip include: spine, vascular, metabolic and malignancy. Causes that are Intrinsic to the hip can either be Extracapsular (iliopsoas tendonitis and trochanteric bursitis) or Intracapsular (sepsis, loosening, thigh pain, prosthetic failure). Painful MoM THA causes related to the bearing couple: There are now described a number of possible clinical scenarios and causes of pain that relate to the metal-on-metal bearing couple itself: a) local hypersensitivity reaction without a significant soft tissue reaction; b) local hypersensitivity reaction with a significant soft tissue reaction; c) impingement and soft tissue pain secondary to large head effect. Metal ions: obtaining serum, or whole blood, cobalt and chromium levels is recommended as a baseline test. However, there is no established cutoff level to determine with certainty if a patient is having a hypersensitivity reaction. A 7 parts per billion cutoff has been suggested. This gives high specificity, but poor sensitivity. Metal ions therefore can be used as a clue, and one more test in the workup, but cannot be relied upon in isolation to make a diagnosis. MARS MRI: a useful tool for demonstrating soft tissue involvement, but there are many painless, well-functioning MoM implants that have soft tissue reactions, that don't require a revision. In the painful MoM hip an MRI, or ultrasound, is recommended to look for soft tissue destruction or a fluid-filled periprosthetic lesion (pseudotumor). Significant soft tissue involvement is concerning and is commonly an indication for revision in the painful MoM hip. Treatment: management of the painful MoM hip is directly related to the etiology of the pain. Unique to MoM bearing is the issue of pain secondary to a local hypersensitivity reaction. All above tests should be utilised to help determine the best course of action in any individual patient. The painful MoM bearing, that is demonstrating significant soft tissue involvement is a concerning scenario. Earlier revision, to prevent massive abductor damage, would seem prudent for these patients. The painful MoM bearing with no significant soft tissue changes can probably be followed and reviewed at regular intervals. If the pain persists and is felt to be secondary to a hypersensitivity reaction, then revision is really the only option, although the patient must be cautioned regarding the unpredictable nature of the pain relief

Background. Periprosthetic joint infection (PJI) remains challenging as a “gold standard” for diagnosis has not yet been established. The aim of this study was to evaluate the accuracy of synovial fluid procalcitonin (SF-PCT) and serum procalcitonin as diagnostic biomarker for PJI and compared their accuracy with standard methods. Materials and Methods. A single-centered prospective cohort study was conducted between 2015–2017 in 32 patients with painful hip or knee arthroplasty underwent revision surgery. Relevant clinical and laboratory data were collected. PJI was diagnosed based on the 2013 international consensus criteria. Preoperative blood sample and intraoperatively acquired joint fluid were taken for PCT measurement with a standard assay. Diagnostic accuracy was analyzed by the receiver-operating characteristic (ROC) curve and the area under the curve (AUC). Results. Twenty patients (62.5%) were classified as PJI, and 12 of them (37.5%) were classified as aseptic loosening group. The median age was 68 years (range 38–87 years). The median values of SF-PCT and serum PCT in PJI group were both significant higher than those in aseptic loosening group: the median serum PCT levels (interquartile range: IQR) were 0.33 ng/mL (0.08–2.79 ng/mL) in PJI group compared with 0.04 ng/mL (0.03–0.06 ng/mL), and the median SF-PCT levels (IQR) were 0.16 ng/mL (0.12–0.26 ng/mL) in PJI group compared with 0.00 (0.00–0.00 ng/mL) (p<0.001 both) (Fig 1). SF-PCT, with a cut-off level as 0.08 ng/mL, had a AUC of 0.87, a sensitivity of 90.0% and a specificity of 83.3%, and a negative likelihood ratio (LR-) of 0.12. Whereas serum PCT, with a standard cut-off level as 0.5 ng/mL, had a AUC of 0.70, a sensitivity of 40.0% and a specificity of 100.0%, and a LR- of 0.60. (Fig 2–3). Conclusion. SF-PCT appears to be a reliable test and could be useful as an alternative indicator or in combination for the diagnosis of PJI

Aim. Autologous-labeled leukocytes combined with sulfur colloid bone marrow scan is the current imaging modality of choice for diagnosing prosthetic joint infection (PJI). Although this technique is reliable, in-vitro leukocyte labeling raises technical difficulties that limit its widespread use and sulfur colloid is increasingly difficult to obtain. Therefore, valid alternatives are needed. The purpose of our study was to determine the clinical value of 99mTc-sulesomab combined with 99mTc-colloidal rhenium sulphide (nanocolloid) bone marrow imaging in the diagnosis of infection in painful total joint arthroplasties. Materials and methods. A retrospective study was conducted on a cohort of 53 patients with painful hip or knee prostheses that underwent 99mTc-sulesomab and 99mTc-nanocolloids sequentially, between January 2008 and December 2016. The combined images were interpreted as positive for infection when there was activity on the sulesomab scan without corresponding activity on the bone marrow scan. The final diagnosis was made with microbiological findings or by clinical follow up of at least 12 months. Results. There were 49 total knee and 4 total hip replacements. Forty of them were women, with an average age of 65 years. Infections were diagnosed in 5 of the 53 patients. An isolated 99mTc-sulesomab scan shows 100% sensitivity but only 29.4% specificity. Combining it with a 99mTc-nanocolloid bone marrow scan, the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 100%, 95.8%, 81.4%, 100% and 96.2% respectively. Conclusion. 99mTc-sulesomab combined with 99mTc-nanocolloid showed to be a useful method for diagnosing prosthetic joint infections. These technically simpler and ready-to-use products may be an alternative to autologous-labeled leukocytes/sulfur colloid marrow scan, although it needs validation at a larger scale

Effectiveness of Liposomal Bupivacaine for Post-Operative Pain Control in Total Knee Arthroplasty: A Prospective, Randomised, Double Blind, Controlled Study. Pericapsular Injection with Free Ropivacaine Provides Equivalent Post-Operative Analgesia as Liposomal Bupivacaine following Unicompartmental Knee Arthroplasty. Total Knee Arthroplasty in the 21st Century: Why Do They Fail? A Fifteen-Year Analysis of 11,135 Knees. Cryoneurolysis for Temporary Relief of Pain in Knee Osteoarthritis: A Multi-Center, Prospective, Double-Blind, Randomised, Controlled Trial. Pre-Operative Freezing of Sensory Nerves for Post-TKA Pain: Preliminary Results from a Prospective, Randomised, Double-Blind Controlled Trial. Proximalization of the Tibial Tubercle Osteotomy: A Solution for Patella Infera during Revision Total Knee Arthroplasty. Treatment of Periprosthetic Joint Infection Based on Species of Infecting Organism: A Decision Analysis. Alpha-Defensin Test for Diagnosis of PJI in the Setting of Failed Metal-on-Metal Bearings or Corrosion. Risk of Reinfection after Irrigation and Debridement for Treatment of Acute Periprosthetic Joint Infection following TKA. Serum Metal Levels for the Diagnosis of Adverse Local Tissue Reaction Secondary to Corrosion in Metal-on-Polyethylene Bearing Total Hip Arthroplasty. Intra-Articular Injection for Painful Hip OA - A Randomised, Double-Blinded Study. Six-Year Follow-up of Hip Decompression with Concentrated Bone Marrow Aspirate to Treat Femoral Head Osteonecrosis. No Benefit of Computer-Assisted TKA: 10-Year Results of a Prospective Randomised Study

Introduction. Metal Artefact Reduction Sequence (MARS) MRI is being increasingly used to detect soft tissue inflammatory reactions surrounding metal-on-metal hip replacements. The UK MHRA safety alert announced in April 2010 recommended cross-sectional imaging such as MRI for all patients with painful MOM hips. The terms used to describe the findings include bursae, cystic lesions and solid masses. A recently used term, pseudotumour, incorporates all of these lesions. We aimed to correlate the pattern of abnormalities on MRI with clinical symptoms. Method. Following our experience with over 160 MARS MRI scans of patients with MOM hips we recognized patterns of lesions according to their: wall thickness, T1/T2 signal, shape, and location. We categorised the 79 lesions from 159 MARS MRI scans of into our novel classification scheme of 1, 2a, 2b and 3. There were two groups of patients: well functioning and painful. Results. We found a surprisingly high prevalence of lesions on MRI scan in the well functioning group (11 out 23, 48%) when compared to the painful group (79 out of 137, 57%). However, there were a significantly greater number of grade 1 lesions in the well functioning group. We suggest that these are post-surgical changes and should not be confused with pathological, tissue destroying lesions. Discussion. This is the largest ever study of patients with MARS MRI scans of MOM hips. It is the first to use a classification system and the first to compare well functioning with painful hips. We are now able to provide radiologists and surgeons with clinical interpretation of a lesion on MRI scan. Our classification system will provide useful information on both symptomatic and asymptomatic patients. Longitudinal follow up of these patients will provide the final validation

Aim. A key of success in the treatment of prosthetic joint infection (PJI) is the proper diagnosis. There is a lack of diagnostic tools able to diagnose a PJI with high accuracy. Alpha-defensin has been proposed as possible solution but the available literature is still limited. This prospective study was carried out in order to determine (1) what is the sensitivity, the specificity, the positive and the negative predictive value of the Alpha-defensin immunoassay test in diagnosing PJI; (2) which clinical features may be responsible for false positive and false negative results?. Method. Preoperative aspiration was performed in patients presenting with a painful hip/knee arthroplasty. Metallosis, other inflammatory comorbidities and previous/concomitant antibiotic therapy were not considered as exclusion criteria. Patients with inadequate amount of synovial fluid for culture were excluded. At time of revision synovial fluid samples were taken in the OR in order to perform Alpha-defensin assay. During surgical debridement tissue samples for cultures were obtained. Prospectively, 156 patients (65 knees and 91 hips) were included. A diagnosis of PJI was confirmed in 29 patients. Results. The sensitivity of the Alpha-defensin immunoassay was 97% (95% CI, 92% – 99%), the specificity was 97% (95% CI, 92% – 99%), the positive predictive value was 88% (95% CI, 81% – 92%) and the negative predictive value was 99% (95% CI, 96% – 99%). Among four false positive patients two had a metallosis and one had a polyethylene wear. The false negative case presented with a draining sinus, and intraoperative cultures were also negative. Conclusions. Alpha-defensin assay may have a significant role in PJI diagnosis. Negative tests may exclude the diagnosis of PJI. Positive tests are very much likely to confirm PJI, but other conditions (metallosis, poly wear) should be excluded

A-70-year old woman underwent uncomplicated total hip arthroplasty using a titanium modular stem with a 46mm CoCr femoral head, a titanium shell, and a metal linear (Wright Medical Technology). Eight years after implantation, she presented with a painful left hip. A pelvic radiograph revealed adequate positioning of both hip implants without any signs of wear of loosening. CT scanning confirmed the presence of a 5 × 5 cm soft tissue mass in the ilium above the cup component accompanied by the iliac fracture. The patient was diagnosed as having an adverse reaction to metal debris (ARMD) after a metal-on-metal THA and revision was performed. Perioperatively?tissue necrosis and partial destruction of the abductor mechanism were found in the absence of any macroscopic infection. Both the neck trunnion and bore of the head showed slight signs of corrosion. The modular neck was revised with a ceramic 28mm head and a new dual-mobility liner(Zimmer Biomet). The iliac fracture was fixed with a porous trabecular metal augment(Zimmer Biomet). The histopathology of tissue sample revealed extensively necrotic material with focal cellular areas of inflammatory cells containing macrophages and neutrophilas. Metalic debris was also scattered in the necrotic materials. After the revision, the patient was recovered without pain or dislocation, and iliac fracture was well fixed. Instability is a substantial problem in the revision of ARMD. Extensive necrosis with gross deficiency of the abductor mechanism is associated with postoperative dislocation. Revision of failed MoM THA a dual-mobility device an effective strategy

Background. Revision surgery for a failed metal on metal (MoM) hip arthroplasty is often unpredictable and challenging due to associated massive soft tissue and bony lesions. We present the analysis and early outcomes of revision surgery in failed MoM hip arthroplasties at our institution. Methods. We have retrospectively analysed the findings and outcomes of revision surgery in 61 failed MoM hip arthroplasties performed between 2009 and 2014. These patients were identified in the special MoM hip surveillance pathway. All these patients underwent clinical assessment and relevant investigations. Intra-operative and histopathological findings were analysed. Results. There were 24 male and 37 female patients with an average age 63.67 yrs. Of the 61 patients, 39 were revised for pseudocysts, 10 for painful hip with raised metal ion levels and the remaining cases for aseptic loosening, malposition and periprosthetic fracture. Average follow up was 12 months. Pre-op and Post-op Oxford hip scores were recorded. One death and one intra-operative periprosthetic fracture was observed. There were no dislocations but one post-op infection was observed. Conclusions. A dedicated MoM pathway helps to identify early failures. A thorough knowledge of failure mechanisms combined with appropriate early and effective surgical intervention may help achieve good clinical outcomes

Metal-on-metal bearings (MoM) saw an increase in global utilisation in the last decade. This peaked in 2008 in the US, with approximately 35% of bearings being hard-on-hard (metal-on-metal, or ceramic-on-ceramic). Beginning in 2008, reports began to surface regarding local soft tissue reactions and hypersensitivity to MoM bearings. A major implant manufacturer recalled a resurfacing device in 2010 after national joint registries demonstrated higher than expected revision rates. Patients with painful MoM bearings are a difficult diagnostic challenge. The surgeon must go back to basic principles, perform a complete history and physical exam, obtain serial radiographs and basic blood work (ESR, CRP) to rule out common causes of pain and determine if the pain is, or is not, related to the bearing. The Asymptomatic MoM Arthroplasty: Patients will present for either routine follow up, or because of concerns regarding their bearing. It is important to emphasise that at this point the vast majority of patients with a MoM bearing are indeed asymptomatic and their bearings are performing well. The surgeon must take into account: a) which specific implant are they dealing with and what is its track record; b) what is the cup position; c) when to perform metal ion testing; d) when to perform further soft tissue imaging (MARS MRI, Ultrasound); e) when to discuss possible surgery. Painful MoM THA causes not related to the bearing couple: These can be broken down into two broad categories. Causes that are Extrinsic to the hip include spine, vascular, metabolic and malignancy. Causes that are Intrinsic to the hip can either be Extracapsular or Intracapsular. Painful MoM THA causes related to the bearing couple: There are now described a number of possible clinical scenarios and causes of pain that relate to the MoM bearing couple itself: A) Local hypersensitivity reaction without a significant soft tissue reaction; B) Local hypersensitivity reaction with a significant soft tissue reaction; C) Impingement and soft tissue pain secondary to large head effect. Factors related to a hypersensitivity reaction: Some patients, and prostheses, seem to be at a higher risk of developing issues following a MoM bearing, although our understanding of the interplay of these factors is still in evolution: patients at risk include all women and patients with smaller component sizes. Implant factors play a role with some implants having higher wear rates and being more prone to corrosion. Special tests: There is ongoing confusion related to the relative value of the various special tests that patients with a painful MoM undergo. A) Metal Ions - obtaining serum, or whole blood, cobalt and chromium levels is recommended as a baseline test. However, there is no established cutoff level to determine with certainty if a patient is having a hypersensitivity reaction. Metal ions therefore can be used as a clue, but cannot be relied upon in isolation to make a diagnosis. B) MARS MRI - a useful tool for demonstrating soft tissue involvement, but there are many painless, well-functioning MoM implants that have soft tissue reactions, that don't require a revision. In the painful MoM hip an MRI, or ultrasound, is recommended to look for soft tissue destruction or a fluid-filled periprosthetic lesion (pseudotumor). Significant soft tissue involvement is concerning and is commonly an indication for revision in the painful MoM hip. C) CT imaging - can be utilised to help determine cup position and combined anteversion, however, plain radiographs can give a rough estimate of this as well, so routine CT scan evaluations are not currently recommended. The painful MoM bearing, that is demonstrating significant soft tissue involvement is a concerning scenario. Earlier revision, to prevent massive abductor damage, would seem prudent for these patients. The painful MoM bearing with no significant soft tissue changes can probably be followed and reviewed at regular intervals. If the pain persists and is felt to be secondary to a hypersensitivity reaction, then revision is really the only option, although the patient must be cautioned regarding the unpredictable nature of the pain relief

Optimal sampling for culture-based or molecular diagnosis remains highly contested for patients suspected of prosthetic joint infection (PJI). Most existing studies have a retrospective design without a standardized sampling strategy. Therefore, the results are difficult to translate into guidelines. We have conducted a 2-year prospective study with a sampling strategy adaptable to the specific procedure in patients with either hip or knee alloplasty. Thus, comparisons of results obtained with different specimen types and diagnostic methods are possible. The study enrolled patients with a painful hip or knee alloplasty. The sampling strategy for microbiological diagnosis included multiple specimens of each type (joint fluid, tissue biopsies, bone biopsies, and swabs taken from the prosthesis in situ), and prosthetic components (if removed). Prepacked boxes with containers and accessories for sampling, transport and storage were provided. Microbial culture and bacterial 16S rDNA screening were carried out for all specimen types. Whenever positive upon 16S rDNA screening, samples were analyzed further by sequencing. Peptide nucleic acid-fluorescence in situ hybridization (optimized using filtrations; Filter-PNA-FISH) was limited to a subset thereof. An overall completeness of ∼90% was obtained by the sampling strategy in 164 procedures (‘cases’) in 131 patients. In 58 cases PJI was suspected, and a revision was carried out. 42 cases were culture-positive, and 16 were culture-negative; one culture-negative case was positive by 16S rDNA sequencing of a corresponding specimen. The contribution to a microbiological diagnosis was high for periprosthetic tissue biopsies (≥ 3 positive out of 5) 90%, prosthetic component(s) 90%, and joint fluid 94%. Conversely, the contribution was sparse for prosthetic swabs 50% and bone biopsies 40%, respectively. Filter-PNA-FISH was used to confirm findings by culture and to demonstrate biofilm formation. With the described sampling strategy we reached high completeness of complex specimen sets. The sampling strategy may be adapted to other clinical settings with microbiological sampling of similar complexity. We found multiple periprosthetic tissue biopsies, prosthetic component(s) and joint fluid to form the optimal specimen set for culture-based diagnosis. The contribution by 16S rDNA sequencing is still under investigations but the contributions seems moderate probably because of a low rate of antibiotic therapy before the procedure, use of effective culture methods and prolonged incubation (14 days)

Accurate detection of migration of hip arthroplasty stems without the burden of bone markers and stereo-radiographic equipment is of interest. This would facilitate the study of stem migration in an experimental setting, but more importantly, it would allow assessing stem loosening in patients with a painful hip outside a study protocol. We developed and validated a marker-free automated CT-based spatial analysis method (CTSA) to quantify stem-bone migration in successive CT scan acquisitions. First, we segmented the bone and stem within both three-dimensional images, then we pairwise registered those elements (Fig. 1). By comparing the rigid transformations of stem and bone, we calculated the migration of the stem with reference to the bone and transferred the three translation and three rotation parameters to an anatomic coordinate system. Based on the rigid transformation, we also calculated the point of the stem that presented the maximal migration (PMM). Accuracy was assessed in a stem-bone model (Fig. 2) by imposing 39 predefined stem rotations and translations, and by comparing those with values calculated with the CTSA tool. In all cases, differences were below 0.20 mm for translations and 0.19° for rotations (95% tolerance interval (95% TI) below 0.22 mm and 0.20°, largest standard deviation of the signed error (SDSE) 0.081 mm and 0.057°). Precision was defined as stem migration calculated in eight clinical relevant zero-migration scenarios. In all cases, precision was below 0.05 mm and 0.08° (95% TI below 0.06 mm and 0.08°, largest SDSE 0.012 mm and 0.020°). The largest displacement of the PMM on the stem was 0.169mm. The precision estimated in five patients was very dependent on the CT scan resolution and was below 0.48 mm and 0.37° (95% TI below 0.59 mm and 0.61°, largest SDSE 0.202 mm and 0.279°, largest displacement of the PMM 0.972 mm). In optimized conditions, the precision in patients improved largely and was below 0.040 mm and 0.111° (largest SDSE 0.202 mm and 0.279°, largest displacement of the PMM 0.156 mm). Our marker-free automated CT-based spatial analysis can detect hip stem migration with an accuracy and precision comparable to that of radiostereometric analysis (RSA), but without the burden of bone markers and the cost of stereo-radiographic equipment. As such, we believe our tool could make accurate measurement of stem migration available to departments without access to RSA and boost this type of research. Moreover, as CTSA does not rely on bone makers, it is applicable to all-comers with a painful hip arthroplasty. Indeed, in those patients with a reference CT scan after hip replacement, a new CT scan could demonstrate stem migration. If no initial CT scan is available, a reference scan could be taken during a first visit and repeated later. Additionally, a “stress test” of the hip could be performed. During such test, comparing CT images acquired during forced maximal intern and external rotation could demonstrate stem loosening

Purpose. The outcome of idiopathic chondrolysis in South Africa has been reported as a progressive downhill course resulting in a painful, stiff hip (Jones 1971, Sparks&Dall 1982). The cause of the disease remains unknown. Theories suggested are mechanical (decreased movement with loss of synovial nutrition; increased joint pressure) and an auto-immune response in genetically predisposed individuals. Our experience with continuous passive motion (CPM) and anti-inflammatory treatment has been disappointing. Method. In order to improve our understanding of the disease and our results, we prospectively studied 5 consecutive patients. All the patients had a subtotal capsulectomy (Roy&Crawford 1988) to relieve intra-articular pressure and correction of the flexion and abduction deformities. Post-operative treatment was with anti-inflammatories and CPM. Results. The patients were adolescent females between 10 and 12.5 years old. They presented with stiff, painful hips with flexion, abduction and external rotation deformities. They had normal auto-immune markers. Radiographs revealed osteopenia and joint space narrowing. CT confirmed osteopenia and joint space narrowing. Three patients had subchondral erosions (two on either side of the joint and one on the acetabular side only). MRI showed bone oedema and confirmed the erosions. Histology of the synovium showed non-specific chronic inflammation with lymphocyte and plasma cell infiltration suggesting an auto-immune cause. Histology of the cartilage showed a superficial layer of fibrous tissue, then a layer of degenerate chondrocytes, with normal chondrocytes in the deep layer. Post-operatively patients had improved range of motion. At mean follow up of 7.8 months the patients had a repeat MRI to assess cartilage regeneration. NO DISCLOSURES

Introduction. Core decompression is used in precollapse lesions to forestall disease progression in avascular necrosis (AVN) of femoral head (FH). The author reports a new technique using reverse bone graft technique to effectuate core decompression. Aim. To prevent precollapse in Ficat Type 1&2 and revascularization using synthetic bone graft material. Methods. A 18 year female police trainee with Magnetic Resonance Imaging (MRI) confirming AVN Stage 2 Ficat, clinically painful hip not evident in x-rays consented to undergo this new technique. Reverse bone graft technique with a Coring reamer – Patent 5423823. A minimally invasive technique with lateral 2 cm incision introducing 8.5 mm core reamer to remove a core of bone up to the subchondral bone. The subchondral cyst decompressed and curetted under video recorded Image Intensifier (II). Demarcated avascular bone segment excised and bone graft reversed and inserted with cortical bone acting as a support to prevent collapse and the distal segment augmented using 5 grams of osteoconductive granular synthetic bone graft material based on calcium phosphate hydroxyapatite (HA 2500–5000 μm). Avascular segment histopathologically confirmed AVN. The metaphyseal entry was extrapoliated at the lateral cortex using the combined necrotic angle described by Kerboul in the anteroposterior and lateral views under II. Protected weight bearing for 2 months to prevent stress riser. Biomaterials. HA granules named as GranuMas™ developed under Intensified Research in Priority Areas (IRPA) Research Project (No. 03-01-03-0000-PR0026/05) and invented by the Advance Materials Research Centre (AMREC) and manufactured by GranuLab –Patent P1 20040748 fulfilling the criteria for American Society for Testing and Materials (ASTM) F1185-88(1993) Standards which is ‘Standard Specification for Composition of Ceramic Hydroxyapatite for Surgical Implants’. Derived from Malaysian limestone, ranging from 200–5000 μm gamma sterilized. Results. After 6 months, there was no collapse of subchondral bone and the FH showed revascularization along bone grafted site with viable graft and increased radiotracer activity using 99-Tc MDP Bone Planar Scintigraphy. Clinical analysis follow up at 2 years was descriptive rather than statistical with a x-ray evident incorporated graft and with pain free full range of movement. Discussion. Reduction in intraosseous pressure is achieved by using large bore 8.5 mm coupled with HA granules promoting revascularization. The core tract entering through the metaphyseal region reduces risk of subtrochanteric fracture a potential complication of vascularized fibular grafts and with less morbidity with other treatment methods for osteonecrosis of the femoral head. The concept can be extended in introducing stem cell and biologic material to treat AVN. Conclusion. This technique is minimally invasive and effective in young patients with early stage of FH AVN and has shown revascularization along the bone grafted site

Aim. Alpha-defensin was recently introduced as a new biomarker having a very high accuracy to rule out periprosthetic joint infection (PJI). A new rapid lateral flow version of the Alpha-defensin test was developed and introduced to detect high levels of Alpha-defensin in synovial fluid quickly and with ease. We conducted a single-centre prospective clinical study to compare the results of the Alpha-defensin rapid test* against the conventional diagnostics according to MSIS criteria. Method. A total of 223 consecutive patients with painful total hip or knee arthroplasty were enrolled into the study. In all patients, blood C-reactive protein was measured and joint aspirations were performed. From the synovial fluid a leukocyte cell count with granulocyte percentage, microbiology cultures and Leukocyte Esterase tests were carried out according to the recommendation of MSIS for diagnosing PJI. At the same time, the Lateral Flow Test* was performed from the aspirate. 191 subjects with 195 joint aspirations (96 hips, 99 knees) were included in final clinical and statistical evaluation. We had 119 joints with an aseptic revision and 76 joints with PJI. Results. After statistical analysis the overall sensitivity of the Lateral Flow Test* was 92.1% (95% confidence interval [CI], 83.6% to 97.1%), the specificity was 100% (95% CI, 97.0% to 100%), the positive predictive value was 100% (95% CI, 94.9% to 100%), and the negative predictive value was 95.2% (95% CI, 89.9% to 98.2%). The overall accuracy of the Lateral Flow Test* was 96.9% (189 of 195, 95% CI, 93.4% to 98.9%). Conclusions. Our results suggest that the PJI test* has a very high accuracy in diagnosing infected THA and TKA. Though the Lateral Flow Test* does not provide information on the identity of the infectious pathogen, the test does have an important role in recognizing PJI early and enables surgeons to start proper therapy without delay. *Synovasure®

Aim. The aim of the study was to assess the accuracy of the alpha defensin lateral flow test for diagnosis of periprosthetic joint infection (PJI) using an optimized diagnostic algorithm and three classification systems. In addition, we compared the performance with synovial fluid leukocyte count, the most sensitive preoperative test. Method. In this prospective multicenter study we included all consecutive patients with painful prosthetic hip and knee joints undergoing diagnostic joint aspiration. Alpha defensin lateral flow test was used according to manufacturer instructions. The following diagnostic criteria were used to confirm infection: Musculoskeletal Infection Society (MSIS), Infectious Diseases Society of America (IDSA) and Swiss orthopedics and Swiss Society of Infectious Diseases (SOSSID). In the latter, PJI was confirmed when at least one of following criteria applied: macroscopic purulence, sinus tract, positive cytology of joint aspirate (>2000 leukocytes/μl or >70% granulocytes), histological proof of acute inflammation in periprosthetic tissue, positive culture (from aspirate, tissue or sonication fluid). Infection was classified as chronic, if symptom duration was more than 3 weeks or if infection manifested after more than 1 month after surgery. The sensitivity and specificity of the alpha defensin lateral flow test and leukocyte count in synovial fluid were calculated and compared using McNemar Chi-square test. Results. Of 151 included patients evaluated for painful prosthetic joints (103 involved knees, 48 hips), the median patient age was 69 years (range, 41–94 years) and 75 patients were female. Systematically evaluating the included patients according to the different diagnostic criteria, MSIS and IDSA revealed both 33 patients with PJI (22%), whereas SOSSID disclosed 47 septic failures (31%), among them 36 chronic infections (77%). Sensitivity of the test was 79% when applying MSIS criteria, 70% with IDSA criteria and 57% with SOSSID criteria. Specificity ranged from 96% (IDSA) to 98% (MSIS) and 99% (SOSSID). Applying the most stringent definition criteria (SOSSID), leukocyte count showed significantly higher sensitivity than the alpha defensin lateral flow test (91% vs. 57%, p<0.001), especially in chronic infections (88% vs. 48%, p<0.001.) In acute infections, both tests detected all infection cases. Processing turnaround time was shorter in Alpha defensin lateral flow test than automated leukocyte count (10 min vs. 2–4 hours). Conclusions. Semi-quantitative alpha defensin test was rapid and highly specific for diagnosing PJI (> 95%). However, sensitivity was limited, especially when applying definition criteria including also low grade infections (SOSSID criteria). Therefore, the alpha defensin lateral flow test does not allow a reliable exclusion of PJI, especially not in chronic infections but may be used as confirmatory test

In this study we evaluated the performance of the newly available ITI-Cartridge (UniveroTM i60 implant and tissue infection (ITI) multiplex polymerase chain reaction (PCR) System, Curetis®, Holzgerlingen, Germany) in diagnosing periprosthetic joint infection (PJI). 30 patients that received an operative revision in the orthopaedic department of the University Hospital Bonn due to suspected PJI or aseptic loosening of a painful total hip or knee arthroplasty between Januar 2014 and November 2014 were included in this retrospective study. The microbiological workup included a minimum of three periprosthetic tissue specimens, joint aspirate and the explanted foreign body for sonication were investigated. Additionally, histopathological examination of the periprosthetic membranes, cell counting of the joint aspirate and multiplex PCR diagnostic of the sonication fluid cultures and of the joint aspirate were performed. All patients were summarized in two diffrent groups (PJI vs. free of infection) according to the classification of the International Consensus Group on Periprosthetic Joint Infection [4]. In our collective sonication fluid cultures had a sensitivity of 88.89% with a specificity of 61.54%. Other microbiological specimens, especially tissue samples and joint aspirates showed both a sensitivity of 66.67%, and a specificity of 92.31% and respectively 84.62%. PCR-based rapid testing of sonication fluid yielded out a sensitivity of 50% with a specificity of 100%. PCR of the joint aspirate documented a slightly better sensitivity of 55.56 % with a specificity of 100%. When summarized these two PCRs the sensitivity rose to 66.67% with a specificity of 100%. In summary, PCR-diagnostic is an additional method to gain ancillary informations in diagnosing PJI but it has to be interpretated carefully in synopsis with the results obtained from tissue cultures, sonication fluid cultures, histopathological examination and clinical course. The performance of the newly available multiplex PCR system ITI-Cartridge did not persuade us, so that PCR diagnostic of sonication fluid culture or joint aspirate was not included in our algorythm of diagnosing PJI

INTRODUCTION:. Management of developmental dysplasia of hip in adult is challenging and needs more to be understood in terms of ideal implant, position of acetabulum and operative technique. Patient may present very late, usually when osteoarthritic changes develop followed by pain. Operative management is difficult because of hypoplastic femoral medullary canal and shallow acetabulum filled with soft tissues. Altered anatomy of neurovascular structures also pose a risk of being injured during surgery. AIMS:. The goal of this study was to evaluate late results of total hip arthroplasty in adults after a minimum of 5 years follow-up. MATERIAL:. 45 Total hip arthroplasties in 40 patients were performed for painful hip dysplasia between 2003 and 2012. These 45 procedures were performed in 40 patients mean aged 32 +/− 14 years [17–56]. 29 patients (32 hips) were males and 11 patients (13 hips) were females. Non cemented total hip arthroplasty was done in all cases with mean follow up of 6 years. Of the 45 hips, 6 were neglected, dislocated hips with proximal migration of femoral head. In such patients sub-trochanteric osteotomy was done to bring the femoral head up to the level of Acetabulum. 5 patients (5 hips) were lost to follow up; consequently, the functional results were evaluated for 40 hips (35 patients). Harris hip score was used to evaluate the functional and clinical results. RESULTS and CONCLUSION:. Harris hip score improved in all patients. We concluded from this series that total hip replacement should be considered in all patients with painful dysplastic hip. Key words: Developmental Dyplasia Hip, Total Hip Arthroplasty

The Pelvic Support Osteotomy (PSO) or Ilizarov Hip Reconstruction(IHR) is well described for the treatment of septic sequelae of infancy. The purpose of this study was to clinically, functionally and radiographically assess our short-term results of this procedure. 25 patients (16 boys, 9 girls) who had undergone a IHR using the Ilizarov/TSF construct over a period of 10 years for a variety of pathologies were reviewed. The mean age at surgery was 15 years 4 months. The pre-operative diagnoses were SCFE(10), hip sepsis (6), DDH (6) and Perthes (3). All had significant leg length discrepancies, 16 had a painful stiff hip, 6 had a painful mobile hip and 3 had a painless unstable hip. At surgery, a mean measured proximal valgus angle of 51° and a mean extension angle of 15° was achieved. Distal femoral lengthening averaged 4.2 cm and distal varus correction was a mean of 8°. The mean fixator time was 173 days. At a mean of 2 years and 7 months follow-up the lower-extremity length discrepancy had improved from a mean of 5.6 cm apparent shortening to 2.3 cm. Trendelenberg sign was eliminated in 18/25 cases. Improvements in range of hip movements and gait parameters were observed. Stance time asymmetry, step length asymmetry, pelvic dip and trunk lurch improved significantly. One patient had conversion to a total hip replacement after 7 years, 4 patients required re-do PSO due to remodelling of the proximal osteotomies, two had heterotopic ossification and two had significant knee stiffness due to lack of compliance. The early results of IHR are encouraging to equalise limb lengths, negate trendelenburg gait, provide a mobile hip with a reasonable axis and the possibility of conversion to THR in the future if needed. Complications need to be anticipated and the effects of remodelling and maintaining adequate knee range of motion must be emphasised