Total Knee Arthroplasty (TKA) patients may present with effusion, pain, stiffness and functional impairment. A positive metal hypersensitivity (positive LTT) may be an indication for a revision surgery with a custom-made implant devoid of any hypersensitivity-related metal or an implant with the least possible ion content of the metal hypersensitivity, if no custom-made is available. The purpose of the current study is to assess the prevalence of metal hypersensitivity in subjects requiring a primary TKA and assess their early functional outcomes. We are recruiting 660 subjects admitted for TKA. Subjects are randomly assigned to 2 groups: oxidized zirconium implant group or cobalt-chrome implant group. Functional outcomes and quality of life (QoL) are measured pre operatively, 3, 6 and 12 months post operatively with WHOQOL-BREF (domain1-Physical Health, domain 2- Psychological, domain 3- Social relationships, domain 4-Environment), KSS, KOOS and pain Visual Analog Scale (VAS). LTT and metal ions are evaluated pre operatively and 12 months post-surgery. One hundred-sixty patients, 98 women, were enrolled in the study. Mean age was 65.6±8.9. Mean follow up (FU) was 7.1±3.8 months. Eighty-one (50.6%) were randomised in the cobalt-chrome group. Infection rate was 1.9%, one patient required debridement. Three patients (1.9%) presented with contracture at three months FU. At 12 months, WHOQOL-BREF domain 1, 2 and 4 improved significantly (p0,05). Overall, all 160 patients improved their functional outcomes and QoL. At 12 months, VAS scores decreased from 7±2.06 at baseline to 1.95±2.79. Furthermore, the high prevalence of positive LTT (27/65) do not seem to affect early functional outcomes and QoL on patients that may have received a potential implant with hypersensitivity (18/27).
Treat to target is the use of a physiologic marker as a monitor of effectiveness or compliance to an intervention. A recent example has been the progressive use of CTX-1 (Marker of osteoclastic activity) as a surrogate of bone resorptive activity in osteoporosis treatment. CTX-1 levels were demonstrated to be inversely related to drug efficacy in the suppression of bone resorption. As far as fragility fractures are concerned, no reference value of CTX-1 for any index fracture sites was found in the literature. In order to prevent subsequent fractures, efforts to better manage this chronic disease are to be explored. The main objective of this study was to compare and validate the use of serum CTX-1 to the perceived compliance to treatment. Five hundred and forty three patients (men and women) 40 years of age or older who had been treated for a fragility fracture were enrolled. The purpose of this study was to correlate the measurement of CTX-1 with the perceived compliance to treatment of patients at the time of fracture and at six, 12 and 18 months after initiation of treatment. Our secondary objectives were to evaluate two different CTX-1 suppression target levels (CTX-1< 0.3 ng/mL and CTX-1<0.2 ng/mL), to determine CTX-1 values according to fracture sites, and to explore the profile of patients with subsequent fractures. Considering index fractures, compliant patients under treatment at baseline had lower CTX-1 levels than non-compliant patients (p=0.052). Patients who were compliant to treatment at six, 12 and 18 months also had lower CTX-1 levels than non-compliant patients (p=0.000). When index fractures were divided into fracture sites, regardless of CTX-1 suppression target level (i.e. CTX-1< 0.3 or 0.2 ng/mL), significant CTX-1 suppression was observed in non-hip and non-vertebral (NHNV) fractures at six, 12 and 18 months (p0.05). No clinically relevant difference was observed between the profile of patients with and without subsequent fractures. The correlation between serum CTX-1 at the time of fracture and at six, 12, 18 months and the perceived compliance to treatment was validated for NHNV fractures supporting the concept of the available treatments and their effects on bone remodeling for this type of fracture. The correlation was not validated for hip neither for vertebral fracture. There was no correlation between CTX-1 levels and subsequent fracture risk.
Total knee arthroplasty (TKA) is recognised as an effective treatment for end-staged knee osteoarthritis. Up to 20% of these patients is unfortunately unsatisfied due to anterior knee pain from unknown origin (Bourne and al. 2010). The aim of this study is to compare knee 3D kinematics during gait of patients with anterior knee pain after TKA to an asymptomatic TKA group. Our hypothesis is that the painful TKA group would exhibit known kinematics characteristics during gait that increase patellofemoral (PF) stresses (i.e. dynamic flexion contracture, valgus alignment, valgus collapse or a quick internal tibial rotation movement) compared to the TKA asymptomatic group. Thirty-eight patients (45 knees) were recruited 12–24 months post-surgery done by one of three experienced orthopaedic surgeons (31 unilateral TKA and seven bilateral TKA, all using the same knee implant). Patients were divided according to their KOOS pain score (with a cut-off at 6/20 to be included in the painful group). The KOOS questionnaire was also used to assess activities of daily living, symptoms, sports and quality of life. A complete clinical and radiological work up was done on the painful group to exclude those with known explanation for pain (i.e. loosening, malrotation, infection and clinical instability). 3D knee kinematics during treadmill walking was captured and computed using the KneeKGTM system. For the painful and asymptomatic groups, demographic results show respectively: age of 64.4 ± 7.6 and 69.8 ± 8.3 years, BMI of 31.9 ± 5.0 and 28.1 ± 3.6 kg.m−2, speed of 1.8 ± 0.6 and 1.67 ± 0.5 miles/h., and 50% of women in each group. Only age and BMI showed to be statistically different between groups. The painful TKA group exhibited a valgus alignment when walking (at initial contact and during stance, p<0.001). No significant difference has been put forward for the flexion/extension and internal/external tibial rotation. Since a higher valgus alignment increases the Q angle, which lateralise the patella and increases PF stresses, results provide new insight on origin of symptoms. Conservative treatments for PF pain syndrome have shown to address the valgus alignment and improve symptoms, therefore the next step will be to assess the impact on pain level and alignment during gait of a personalised conservative management for the painful TKA group. Additionally, a study assessing the change in the radiological and dynamic alignment from pre to post surgery could bring valuable insight on the impact of surgical procedure on anterior knee pain.
A radiation sterilisation dose (RSD) of 25 kGy is commonly recommended for sterilisation of allograft bone. However, the mechanical and biological performance of allograft bone is gamma dose-dependent. Therefore, this study aimed to apply Method 1 – ISO 11137–2: 2006 to establish a low RSD for frozen bone allografts. Two groups of allograft bones were used: 110 femoral heads (FH) and 130 structural and morselized bones (SMB). The method included the following stages: bioburden determination using 10 FHs and 30 SMBs; verification dose selection using table six in the ISO standard and bioburden; the verification dose was used to irradiate 100 samples from each group; then irradiated bone segments were tested for sterility. The criterion for accepting the RSD as valid is that there must be no more than two non-sterile samples out of 100. The radiation sterilisation dose is then established based on table five, ISO 11137– 2: 2006. The bioburden of both types of frozen allograft was zero. The verification dose chosen was 1.3 kGy. Two hundred bone segments were irradiated at 1.3 kGy. The average delivery gamma dose was 1.23 kGy (with minimum dose of 1.05 kGy maximum dose of 1.41kGy), which is acceptable according to the ISO standard. Sterility tests achieved 100% sterility. Accordingly, 11 kGy was established as a valid RSD for those frozen bone allografts. A reduction in the RSD from 25 kGy to 11 kGy will significantly improve bone allograft mechanical and biological performance because our data show that this dose level improves the mechanical toughness and osteoclast activity of the allograft by more than 10 and 100 percent, respectively, compared with bone allografts irradiated at 25 kGy. A low RSD of 11 kGy was established for allograft bones manufactured at Queensland Bone Bank by applying dose validation method 1 (ISO 11137.2-2006) that is internationally accepted.
It is not known if the radiation sterilisation dose (RSD) of 25 kGy affects mechanical properties and biocompability of allograft bone by alteration of collagen triple helix or cross-links. Our aim was to investigate the mechanical and biological performance, cross-links and degraded collagen content of irradiated bone allografts. Human femoral shafts were sectioned into cortical bone beams (40 × 4 × 2 mm) and irradiated at 0, 5, 10, 15, 20, and 25 kGy for three-point bending tests. Corresponding cortical bone slices were used for in vitro determination of macrophage activation, osteoblast proliferation and attachment, and osteoclast formation and fusion. Subsequently, irradiated cortical bone samples were hydrolised for determination of pyridinoline (PYD), deoxypyridinoline (DPD), and pentosidine (PEN) by high performance liquid chromatography (HPLC) and collagen degradation by the alpha chymotrypsin (ïjCT) method. Irradiation up to 25 kGy did not affect the elastic properties of cortical bone, but the modulus of toughness was decreased from 87% to 74% of controls when the gamma dose increased from 15 to 25 kGy. Macrophages activation, the proliferation and attachment of osteoblasts on irradiated bone was not affected. Osteoclast formation and fusion were less than 40% of controls when cultured on bone irradiated at 25 kGy, and 80% at 15 kGy. Increasing radiation dose did not significantly alter the content of PYR, DPD or PEN but increased the content of denatured collagen. Cortical allografts fragility increases at doses above 15 kGy. Decreased osteoclast viability at these doses suggests a reduction in the capacity for bone remodelling. These changes were not correlated with alterations in collagen cross-links but in degradation to the collagen secondary structure as evidenced by increased content of denatured collagen.
This study was designed to be the first to prospectively evaluate CT-guided radiofrequency ablation for osteoid osteoma in terms of pain control, medication consumption, quality of life and patient function. Over two years, forty patients with symptoms and radiographic findings classic for osteoid osteoma were offered radioablation. Patients were asked to fill out facial, subjective and visual analog pain scales and to undergo the Musculoskeletal Tumour Society 1987 functional assessment. Results show immediate and lasting resolution of symptoms, a sharp drop in drug use and a significant improvement in function thus supporting the role of radioablation as first line therapy. The purpose of this study was to prospectively evaluate the usefulness of radioablation for osteoid osteoma in terms of pain control, analgesic drug consumption, quality of life and patient function. Radioablation appears to be a safe and effective method of treatment for osteoid osteoma. It offers immediate and lasting resolution of symptoms. Results support its role as first line therapy. This is the first study to prospectively measure the outcome of patients treated with CT-guided radiofrequency ablation for osteoid osteoma. The mean follow-up time is 6.93 months ( Over two years, forty patients with symptoms and radiographic findings classic for osteoid osteoma who had already received various treatments were offered radioablation. Written consent was obtained and patients were asked to fill out facial, subjective and visual analog pain scales. The Musculoskeletal Tumour Society 1987 functional assessment was performed. This data was collected two weeks prior to treatment and then at two weeks, three months and one year after treatment. The procedure was performed under CT guidance and on a one-day hospital admission basis.
