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Abstract: This work discusses the wear behaviour of two different ultra-high-molecular-weight-polyethylene tibial component designs. Mobile and fixed bearings were tested on a knee wear simulator for 5 million cycles using bovine calf serum as lubricant. We correlated the wear results with the chemical characterisation of the investigated materials: Fourier Transformed Infra Red Spectroscopy analyses, Differential Scanning Calorimetry and cross-link density measurements were used to assess the chemical features of this polyethylene. Mobile and fixed polyethylene inserts showed a different wear behaviour: the mobile designs components showed lower weight losses than the fixed components (109±6mg and 163±80mg, respectively). Significant statistical differences were observed in wear rate (P =0.035, Kolmogorov–Smirnov Test for two samples). From a molecular point of view, typical radiation-induced oxidation profiles were observed in all the tested polyethylene samples, but the overall degradation was more significant in the fixed bearing inserts and this is likely to play a role on the wear performances. [Copyright &y& Elsevier]

An inter and intra rater reliability (INTERR and INTRAR) study was designed. 71 subjects, with primary hip coxarthrosis, were included and randomly divided in a study group (SG= 36) and a control group (CG= 35) to assess the efficacy of the Fascial Manipulation® (FM®) method. The primary objective was the assessment of INTERR and INTRAR about movement verification (MV) and palpation verification (PV) of FM® performed by two physiotherapists (PtA and PtB). The secondary objective was evaluate the efficacy of FM® through MV, PV and pain score. Pain was assessed using the Numeric Rating Scale (NRS). SG received three weekly sessions of FM® byPtA. PtB re-evaluated all the subjects at the end of the study. Results of the INTERR analysis showed for SG: MV (ICC= 0.92, k= 72.7%); PV (ICC= 0.91, k= 75.7%). For CG : MV (ICC= 0.95, k= 84.2%); PV (ICC= 0.90, k= 75%). Results of the INTRAR analysis for SG reported: MV (ICC= 0.82, k= 74,8%); PV (ICC= 0.60, k= 46.8%); for CG: MV (ICC= 0.93, k= 78.7%); PV (ICC= 0.84, k= 53.3%). Statistical significance were reported in NRS (p = 0.001), MV (p = 0.0003) and PV (p < 0.0001) with better results for SG using "Intention To Treat" method. This study demonstrates that FM® assessment procedures have a high reliability even if applied by practitioners with basic experience. Furthermore FM® treatment can improve pain and ROM in individuals with primary coxarthrosis [ABSTRACT FROM AUTHOR]

Introduction: Noise in ceramic-on-ceramic (CoC) total hip arthroplasty (THA) is a potential symptom of abnormal bearing wear. Squeaking and other prosthetic hip noises are multi-factorial phenomena that can be analysed and may provide prognostic information. Methods: 46 patients with noisy CoC bearings were investigated using X-ray, computed tomography and joint fluid analysis, and classified into either high or low risk of ceramic liner fracture groups according to previously published guidelines. Noise events from the bearings of 16 high risk cases which were subsequently revised were compared with 30 patients in the low risk control group who did not undergo revision. Noise events were analysed for their physical characteristics using a standardised protocol and classified as either low frequency and short duration 'clicking' or long duration and high frequency 'squeaking'. Results: The peak frequency of squeaking during forward walking was significantly higher for patients in the case group who were revised, compared with the control group. The patient-reported onset of squeaking (46 months postoperatively) was earlier than short-noise emissions (82 months). In the standardised sequence of movements, short-noise always occurred more frequently than squeaking. Small heads (28 mm) were more likely to develop short-noise, while large heads (⩾32 mm) were more likely to develop squeaking. Discussion: Noise evaluation may provide additional value for predicting failure of CoC bearings, though some questions should be better investigated in a dedicated prospective trial. [ABSTRACT FROM AUTHOR]

Background Ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT) with intrabursal steroid injection is an elective treatment for painful rotator cuff calcific tendinopathy. Purpose To compare the efficacy of post-US-PICT intrabursal 40 mg injection of triamcinolone acetonide (TA) versus methylprednisolone acetate (MA). Material and Methods Forty patients (22 women; mean age 48.7 ± 7.2 years) with painful shoulder calcific tendinopathy, treated with TA or MA injected intrabursally after US-PICT, were included in this randomized controlled trial. At baseline and after 1, 7, 15, 30, 45, and 180 days, patients underwent US and clinical examination, using Constant (CS) and VAS (VS) scores. Complications and analgesic use were also recorded. Results Compared to baseline, at the 45-day follow-up, TA and MA group showed a similar improvement (Δ) in CS (42 ± 10 versus 36 ± 9 points) and VS (-4.4 ± 1.3 versus -3.6 ± 1.3 points). At the 180-day follow-up, the improvement was higher in TA versus MA (ΔCS: 53 ± 7 versus 44 ± 7 points; ΔVS: -4.9 ± 1.1 versus -3.9 ± 1 points). Multivariate analysis showed a mean CS higher ( P = 0.02) in TA versus MA group, while VS was similar. TA had a 5 × higher ( P = 0.007) chance of reaching complete remission (CS = 100 points) than MA group. A progressive decrease in analgesic use, concomitant to a significant and similar reduction of bursitis and calcifications, was observed in both groups. No major complications occurred. Conclusion Two-needle US-PICT with intrabursal steroid injection is safe and effective. The chance of reaching better scores and, even more important for a clinical perspective, of functional recovery, is higher in patients treated with TA than MA. [ABSTRACT FROM AUTHOR]

Ceramic-on-ceramic (CoC) couplings are alternative bearings surfaces that have been reported to reduce osteolysis, wear debris and aseptic loosening compared to the use of polyethylene. Early experiences with ceramics had poor results, but they have led to many improvements in the manufacture and design of subsequent implants.~Introduction~Background~We analysed medical files of 300 CoC total hip arthroplasty (THA) with a modular neck performed during period 1995-2000 by a single surgeon for a minimum follow-up of 13 years, evaluating clinical and radiological outcome.~Methods~Methods~The mean clinical Merle d'Aubigne and Postel hip score at the final follow-up is 17.4, against a preoperative value of 11.4. Overall survivorship with an endpoint of revision is 93.2% (95% CI, 89.0%-97.3%) at 15 years, while considering only prosthesis failures related to aseptic loosening and ceramic breakage, survival rate at 15 years is 97.2% (95% CI, 94.8%-100%). We observed complications that led to revision surgery in 11 patients (4%) (periprosthetic fractures, liner ruptures, septic loosening of the implant, aseptic loosening of the cup, aseptic loosening of the stem). The occurrence of squeaking is low (1.6%, 4 cases) and we analysed the characteristics of these patients.~Results~Results~Our study shows an excellent long term survivorship of third generation alumina CoC THA. We reiterate the importance to have a stable implant to maximise the advantage of ceramic and to avoid complications.~Discussion~Conclusions [ABSTRACT FROM AUTHOR]

Background The repair of the myotendinous junction following total hip arthroplasty is challenging as this region is the weakest part of the muscle structure. This study investigated the mechanical behaviour and the mode of failure of different suturing techniques of the myotendinous junction. A new asymmetrical stitch was compared to two widely used techniques, i.e. the simple stitch (two loops in parallel) and the figure-of-eight stitch. Methods The ovine triceps brachii myotendinous junction was selected as the experimental model. Each technique was sewn in muscle belly on one side and in a polyester belt (no-tendon configuration) or in thin tendon (full configuration) on the other side. The former was chosen to determine the grasping power of the stitch on the muscle despite the tendon quality, the latter to simulate a very thin gluteus medius tendon. Findings The new stitch showed a higher ultimate strength (+ 40%) compared to the two controls in the no-tendon configuration. In the full configuration, no significant increase was observed, although failure of the new stitch always occurred at the tendon side. Furthermore, the new stitch does not alter the stiffness of repair. Interpretation The new stitch has a higher grasping power on muscle belly than the single passing-through stitches thanks to the multiple fixation points, which better distribute the load in the tissue. However, such performance can be fully exploited only in the presence of good quality tendons. [ABSTRACT FROM AUTHOR]

Purpose: Wear and survival of total joint replacements do not depend on the duration of the implant in situ, but rather on the amount of its use, i.e. the patient's activity level. With this in mind, the present study was driven by two questions: (1) How does total knee replacement (TKR) respond to the simulation of daily highly demanding activities? (2) Are certain activities to be advised against or, on the contrary, useful to implanted patients, in order to reduce wear of TKR and its related problems? Methods: One set of the same total knee prosthesis (TKP), equal in design and size, was tested on a three-plus-one knee joint simulator for two million cycles using a highly demanding daily load waveform, replicating a stair-climbing movement. The results were compared with a set of TKP previously tested with the ISO level walking task. A digital microscope was used to characterise the superficial structure of all the TKPs. Gravimetric and micro-Raman spectroscopic analyses were carried out on the polyethylene inserts. Visual comparison with in vivo explants was carried out. Results: The average volumetric mass loss after two million cycles was 44 ± 6 mm. Microscope examinations showed some deep scratches along the flexion/extension movements for all the components. Also, the metallic backside surface showed intense non-linear scratches and the polyethylene counterface was characterised by some craters. A decrease in crystallinity, induced by mechanical stress was observed on all polyethylene components and was quantitatively confirmed by the orthorhombic fraction α value. Conclusions: The results of this study demonstrated that the forces and motion sustained by the knee are highly activity-dependent. Moreover, this test confirmed that under more severe conditions, the material properties change according to a different wear mechanism and a decrease in crystallinity occurs. Loading characteristics for specific activities should be considered for the design of functional and robust TKRs. [ABSTRACT FROM AUTHOR]

Objective: The main goal of this case was to report the treatment of bicondylar fractures of the tibial plateau and the restoration of the metaphyseo-diaphyseal dissociation.Clinical Presentation and Intervention: A 54-year-old male who was cycling had a road accident that caused a closed fracture of the right tibial plateau and proximal fibula diagnosed by X-rays. The patient underwent surgery and was immobilized with a long-leg splint for 4 weeks. After immobilization, aggressive rehabilitation was done. Progressive quadriceps strengthening, movements to improve symmetrical weight bearing, and functional activities were performed. The patient improved muscle strength and obtained high scores for gait and balance in a relatively short time.Conclusion: In this report, a bicondylar tibial fracture treated with a two-incision approach and a double-plate osteosynthesis provided strong fracture stabilization and thereby allowed an early mobilization with aggressive rehabilitation. [ABSTRACT FROM AUTHOR]

Ultra-high molecular weight polyethylene knee prostheses of two different sizes (i.e. characterised by different contact areas) were run on a knee wear simulator in two tests differing for the applied load. Gravimetric and micro-Raman spectroscopic analyses were performed to investigate at macroscopic and molecular levels the effects of contact area and applied load on the morphology of the knee components. The larger prostheses showed a higher mass loss in both tests, while Raman spectroscopy showed a more significant polymer degradation in the smaller prostheses, suggesting that a lower contact area is responsible for a higher wear at the molecular wear, but for a lower gravimetric wear. Raman measurements showed that in the second test (using a higher applied load), the wear mechanism changed with respect to the first test: the less severe conditions used in the latter resulted in an increase in the orthorhombic content, while the more severe conditions used in the former determined an increase and rearrangement of the amorphous phase. The results here reported allow to gain more insights into the effects of contact area, applied load and contact stress on wear. Preliminary micro-Raman analyses on in vivo worn knee prostheses confirmed the results obtained in vitro: the retrievals of smaller size were found more degraded at molecular level than those of larger size. These findings showed that the conditions used in the in vitro tests well simulate the knee kinematics of the knee joint and thus the in vivo wear. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Purpose: The research questions of the present study were: (1) Is total knee prosthesis wear behaviour influenced by implant size, body weight and their combined effect? (2) Are these findings significant and helpful from a clinical point of view?Methods: Two very different sizes of the same total knee prosthesis (TKP), previously tested with ISO 14243 parameters, were tested on a knee simulator for a further two million cycles using a modified ISO 14243 load waveform. Roughness examination was performed on the metallic components. Gravimetric and micro-Raman spectroscopic analyses were carried out on the polyethylene inserts.Results: The average volumetric mass loss was 69 ± 3 mm(3) and 88 ± 4 mm(3) for smaller and bigger size, respectively. Bigger TKPs are little influenced by an increased load, while the wear trend of the smaller TKP showed a redoubled slope, and more significant morphology changes were observed. However, the two sizes seem to behave similarly when subjected to a load increase of 15 %; the slope of the volumetric mass loss trend was comparable for the two sets of inserts, which did not appear significantly different also at the molecular level. Roughness average parameters of the lateral femoral condyle support this evidence.Conclusions: It can be asserted that the body weight and implant size are relevant to the understanding of TKP wear behaviour. A post-implantation body weight increase in a patient with smaller knee dimensions could results in more critical effects on prosthesis long-term performance. [ABSTRACT FROM AUTHOR]

Purpose: The research questions of the present study were: (1) Is total knee prosthesis wear behaviour influenced by implant size, body weight and their combined effect? (2) Are these findings significant and helpful from a clinical point of view? Methods: Two very different sizes of the same total knee prosthesis (TKP), previously tested with ISO 14243 parameters, were tested on a knee simulator for a further two million cycles using a modified ISO 14243 load waveform. Roughness examination was performed on the metallic components. Gravimetric and micro-Raman spectroscopic analyses were carried out on the polyethylene inserts. Results: The average volumetric mass loss was 69 ± 3 mm and 88 ± 4 mm for smaller and bigger size, respectively. Bigger TKPs are little influenced by an increased load, while the wear trend of the smaller TKP showed a redoubled slope, and more significant morphology changes were observed. However, the two sizes seem to behave similarly when subjected to a load increase of 15 %; the slope of the volumetric mass loss trend was comparable for the two sets of inserts, which did not appear significantly different also at the molecular level. Roughness average parameters of the lateral femoral condyle support this evidence. Conclusions: It can be asserted that the body weight and implant size are relevant to the understanding of TKP wear behaviour. A post-implantation body weight increase in a patient with smaller knee dimensions could results in more critical effects on prosthesis long-term performance. [ABSTRACT FROM AUTHOR]

Hip replacement with large metal-on-metal (MoM) coupling has recently been under attention for its metal ions release, inducing several disorders. Since the blood level toxicity threshold for cobalt is known, the aim of this work is to determine whether Co serum and blood levels correlate with the synovial fluid level. Beside this, the synovial fluid Co from patients without prosthesis has also been measured. Co has been determined in 54 samples (32 unilateral MoM and 22 controls) with inductively coupled plasma mass spectrometry in the three matrices. In the prosthesized group, cobalt was significantly higher compared with controls and in the synovial fluid it strongly correlated with whole blood Co ( p = 0.847) and serum ( p = 0.855). Moreover, the Co levels into whole blood and serum were significantly different. In conclusion, haematic Co concentration correctly reflects Co local level. [ABSTRACT FROM AUTHOR]

Abstract: Small and large sized-mobile inserts (i.e. size #2 and size #6) were tested on a knee wear simulator for 2 million cycles, using bovine calf serum as lubricant. Gravimetric and micro-Raman spectroscopic analyses were performed on polyethylene inserts. Roughness analysis was performed on the metallic components. The larger size, i.e. #6, had almost twice weight loss with respect to the smaller one, i.e. #2 (37.8±2.8mg and 19.46±0.93mg, respectively). Significant statistical differences were observed in wear rates (p=0.001, Kolmogorov–Smirnov test for two samples). Raman spectroscopy showed a greater increase in crystallinity for the smaller inserts: upon wear, the orthorhombic content (α o) significantly increased at the expense of the third phase content (α b). [Copyright &y& Elsevier]

Background: Total hip replacement in patients with Legg-Calvé-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-Calvé-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-CalvéPerthes 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. [ABSTRACT FROM AUTHOR]

The first clinical sign of ceramic hip prosthesis failure is hip noise. We therefore investigated whether isolation, observation at scanning electron microscopy, and chemical identification with microanalysis of particles from synovial fluid of 'noisy hip' could be predictive of ceramic damage. Firstly, the level of 'physiological wear' of well functioning ceramic-on-ceramic hip prostheses was assessed with this method, then the test was validated as diagnostic method for liner fracture. Twelve asymptomatic patients were enrolled to demonstrate the first aim; 39 cases of noisy hip (GROUP 1), and 7 cases of pending failure not related to ceramic (GROUP 2) were enrolled for the second aim. The analysis of the synovial fluid of the 12 asymptomatic patients allowed to set the 'physiological wear' threshold. The analysis of GROUP 1 hips demonstrated the presence of ceramic particles (2 physiological, 12 mild, and 25 strong). The analysis of GROUP 2 showed a physiological presence of ceramic particles in all cases. Revision surgery in GROUP 1 was performed in 16 hips out 25 with strong ceramic particle presence and 2 out of 12 with mild ceramic particle presence. Failure of the ceramic component was evident in all but one of these cases, while the integrity of components was demonstrated in all seven hips of GROUP 2. Synovial fluid microanalysis can be a useful surrogate in predicting ceramic failure particularly when a strong presence of ceramic particles is observed. On the contrary there is not enough evidence to predict ceramic failure in presence of mild positivity. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1312-1320, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Preoperative diagnosis of septic loosening hip prosthesis is often challenging. Culture test on joint samples obtained during revision surgery is the diagnostic gold standard while the role of preoperative hip aspiration is still controversial. The aims of this prospective randomized study were to compare the sensitivity, specificity and accuracy of preoperative ultrasound-guided and fluoroscopic-guided aspiration, and to identify associated laboratory parameters or scintigraphy that could help in predicting septic loosing hip prosthesis. Sixty patients affected by persistent pain after hip prosthesis randomly received fluoroscopic-guided or ultrasound-guided hip aspiration before revision surgery. The results of culture tests of joint fluid presurgically and at surgery were compared. In addition, associated blood inflammatory markers and scintigraphy were evaluated. Ultrasound-guided aspiration showed a better sensitivity (69% vs. 27%), specificity (94% vs. 75%) and accuracy (83% vs. 40%) than fluoroscopic-guided aspiration. The combination of ultrasound-guided aspiration and C-reactive protein represents the best model to predict septic loosening hip prosthesis preoperatively. [Copyright &y& Elsevier]

Background: 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. Methods: 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). Results: 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. Conclusions: 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. [ABSTRACT FROM AUTHOR]

The article presents information on a study that determines the diagnosis of ceramic liner fracture. The purpose of the study is to present guidelines for the early recognition of clinical signs of ceramic liner fractures. Liner fractures are usually the consequence of repeated trauma due to head subluxation and their frequency can be underestimated. Liner fractures can be due to multiple causes like dislocation, impingement, and microseparation.

Background: Total hip replacement in patients with Legg-Calvé-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-Calvé-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-Calvé-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. [ABSTRACT FROM AUTHOR]