Serious traumatic injury is a leading cause of death and disability globally, with the majority of survivors developing chronic pain. The aims of this study were to describe early predictors of poor long-term outcome for post-trauma pain. We conducted a prospective observational study, recruiting patients admitted to a Major Trauma Centre hospital in England within 14 days of their injuries, and followed them for 12 months. We defined a poor outcome as Chronic Pain Grade ≥ II and measured this at both 6-months and 12-months. A broad range of candidate predictors were used, including surrogates for pain mechanisms, quantitative sensory testing, and psychosocial factors. Univariate models were used to identify the strongest predictors of poor outcome, which were entered into multivariate models.Background
Methods
Prior research has shown that depression negatively impacts outcomes after total hip arthroplasty (THA); however, arthroplasty patients may also have depressive symptoms without an established diagnosis. The purpose of this study was to determine whether the Patient Health Questionnaire-2 (PHQ-2), a two-question depression screener, correlates with joint-specific symptom improvement after primary THA. This was a prospective cohort study. Patients completed the PHQ-2 and the Hip Disability and Osteoarthritis Outcome Score - Joint Replacement (HOOS-JR) prior to THA, with follow-up at 6 weeks and 6 months. An a priori power analysis determined a sample size of 31 would detect an effect size of 0.5 with a power of 0.80. We used previously established minimum clinically important difference (MCID) values for HOOS-JR. Continuous variables were analyzed with t-tests or Mann-Whitney tests while categorical variables were analyzed with Chi square or Fisher exact tests.Background
Methods
Wear debris generated by total hip replacements (THRs) may cause mechanical instability, inflammation, osteolysis and ultimately implant loosening, thus limiting the lifetime of such devices [1]. This has led to the development of biocompatible coatings for prostheses. Silicon nitride (SiN) coatings are highly wear resistant and any resultant wear debris are soluble, reducing the possibility of a chronic inflammatory reaction [2]. SiN wear debris produced from coatings have not been characterized Commercial silicon nitride particles of <50nm (Sigma Aldrich) were incubated with formalin fixed sheep synovium at a volume of 0.01mm3 /g of tissue (n=3). The tissue was digested with papain (1.56mg/ml) for 6h and subsequently proteinase K (1mg/ml) overnight. Proteinase K digestion was repeated for 6h and again overnight, after which samples appeared visibly homogeneous [Figure 1]. Samples were then subjected to density gradient ultracentrifugation using sodium polytungstate (SPT) [3]. The resulting protein band was removed from the pellet of particles. Control tissue samples, to which no particles were added, were also subjected to the procedure. Particles were washed with filtered water to remove residual SPT using ultracentrifugation and filtered onto 15nm polycarbonate filters. The filtered particles were imaged by cold field emission scanning electron microscopy (CFE-SEM) and positively identified by elemental analysis before and after the isolation procedure. To validate whether the isolation method affected particle size or morphology, imaging software (imageJ) was used to determine size distributions and morphological parameters of the particles. A Kolmogorov-Smirnov test was used to statistically analyse the particle morphology.Introduction
Methods
Our aim was to evaluate the functional outcome of extensile revision knee exposure techniques. 166 revision total knee arthroplasties requiring an extensile exposure with 2 year minimum follow-up were prospectively studied {81 rectus snips (RS), 42 tibial tubercle osteotomies (TTO), and 43 quadriceps turn-downs (QT)}. Patients were clinically evaluated for knee society score, range of motion (ROM) and extensor lag comparing pre-op and 24 month follow-up appointment findings. Radiological evidence of avascular necrosis (AVN) pre &
post operation was recorded. The TTO group was further examined for proximal migration of the tubercle post op. Pre-operative knee motion (75° &
71°) and knee scores (74 &
70) were lower in revision total knee arthroplasties requiring QT &
TTO than those requiring a RS (91° &
84). Post op flexion and knee scores were greater in the RS group (102° &
131) than in the QT (81° &
114) and TTO (84° &
111) groups in whom there was no significant difference. Avascular necrosis of the patella was most commonly seen following QT. In both QT &
TTO groups performing a lateral release was significantly associated with AVN of the patella. Extensor lag (>
10°) was seen only in the QT &
TTO groups (11% &
8%) in whom there was no significant difference. Tubercle escape (>
2mm) in the TTO group was significantly greater (54%) in those where circlage wires only had been used than in those where a proximal transfixation wire was used (11%). In conclusion, both QT &
TTO groups had similarly poor knee scores &
ROM pre &
post operation. AVN of the patella for both groups was similar and significantly associated with performing a lateral release. Finally we would conclude that the use of a through wire significantly reduces tubercle escape in TTO fixation.
