Cost-utility analysis of total knee arthroplasty using 10-year data from a randomised controlled trial: Implant design influences quality-adjusted life year gain.

BACKGROUND: The aim of this study was to perform a cost-utility analysis for total knee arthroplasty (TKA) over a 10-year follow up period. METHODS: Two-hundred and twelve patients were randomised to receive either a Kinemax or a Triathlon TKA. Patients were assessed pre-operatively, and at 6 months, and 1, 3, 7 and 10 years postoperatively. The costs of the primary and revision surgery were accounted for. One-year quality-adjusted life year (QALY) gain was used to estimate 10-year gains using the established annual health gain discounts. RESULTS: Forty-eight patients died and eight were revised during the follow up period. Overall QALY gain per patient over the 10-year period was 2.594 and the cost per patient was £6559, which resulted in a cost per QALY of £2761 at 10 years. The Triathlon group had a significantly greater QALY gain compared with the Kinemax (mean difference (MD) 0.53, 95% CI 0.03-1.03, P = 0.02), which resulted in a cost per QALY for the Triathlon group of £2521 compared with £3107 for the Kinemax group at 10 years. The 5% annual discount resulted in a significantly lower QALY gain (MD 0.135, 95% CI 0.201-0.354, P = 0.002), whereas the 3.5% annual discount resulted in non-significant difference in QALY gain compared with the actual gain (MD 0.021, 95% CI -0.084 to 0.077, P = 0.292). CONCLUSIONS: TKA was a cost-effective intervention, and the Triathlon was associated with a greater cost effectiveness at 10 years. The 3.5% annual discounts for QALY gain would seem to be the most accurate, with an underestimation being observed with the 5% discount.

Preoperative morbidity and joint awareness while awaiting hip arthroscopy for femoroacetabular impingement.

PURPOSE: The Forgotten Joint Score (FJS-12) is a valid tool in the evaluation of patients undergoing hip arthroscopy, assessing the unique concept of joint awareness in the setting of a patient's hip pathology. The preoperative burden on patients' mental wellbeing of impaired joint function or symptoms is well established. The purpose of this study was to determine patients' awareness of their hip joint whilst awaiting hip arthroscopy for femoroacetabular impingement, to explore any association between joint awareness and mental health status, and to determine whether this relates to time spent waiting for arthroscopy preoperatively. METHODS: A prospective database of patients undergoing hip arthroscopy between January 2018 and November 2020 was analysed. All patients with a diagnosis of femoroacetabular impingement (FAI) undergoing arthroscopic treatment were included. Questionnaires included the FJS-12, twelve item international hip outcome tool (iHOT-12), EuroQol 5D-5L (EQ-5D-5L) and the Tegner activity score. Pearson's correlation coefficient was used to assess relationships between continuous variables. RESULTS: Preoperative functional outcomes were completed by 81 patients (97.5%) prior to undergoing hip arthroscopy. Median preoperative FJS-12 score was 16.67 (IQR 8.33 - 29.68). Forty-four patients reported any level of anxiety/depression preoperatively (54.3%). Preoperative FJS-12 showed a significant negative correlation with worsening mental health status (r = - 0.359, p <  0.001), and a significant positive correlation with EQ-5D-5L (r = 0.445, p <  0.001). The duration of symptoms or time on the waiting list did not correlate with increased joint awareness or worsened mental health. CONCLUSION: Joint awareness is high when awaiting hip arthroscopy for FAI. Increasing levels of joint awareness correlate with poorer mental health status and poorer quality of life measures, however these parameters do not seem to be associated with increased duration of symptoms prior to surgery or time on the waiting list for surgery.

The forgotten joint score-12 is a valid and responsive outcome tool for measuring success following hip arthroscopy for femoroacetabular impingement syndrome.

PURPOSE: The forgotten joint score-12 (FJS-12) is an outcome questionnaire designed to evaluate joint awareness. The responsiveness and validity of the English language version of the FJS-12 in patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) is not known. METHODS: Consecutive patients undergoing hip arthroscopy for a diagnosis of FAI were prospectively followed up over a 1 year period. Patients completed preoperative and postoperative FJS-12, EuroQol 5 Dimension (EQ-5D-5L), and the 12-item international hip outcome tool (iHOT-12). We evaluated construct validity with Spearman correlation coefficients for the FJS-12, and responsiveness by way of effect size and ceiling effects. RESULTS: Forty-six patients underwent hip arthroscopy, of which 42 (91%) completed post-operative PROMs at 1 year follow-up. Construct validity was strong with the iHOT-12 (r = 0.87) and also the EQ-5D-5L (r = 0.83). The median postoperative FJS score was 50.2 (IQR 64). The mean change in score for the FJS-12 was 31 points (SD 31) (p < 0.001), with an effect size (Cohen's d) of 1.16. Preoperatively, three patients scored the lowest possible value resulting in a floor effect of 7.1%. Similarly, only three patients (7.1%) scored the best possible score post-operatively. CONCLUSION: This is the first evaluation of the joint awareness concept in the English language version of the FJS-12 following hip arthroscopy for FAI. The FJS-12 is a valid and responsive tool for the assessment of this cohort of patients. LEVEL OF EVIDENCE: II.

A Genetic Epidemiological Mega Analysis of Smoking Initiation in Adolescents.

INTRODUCTION: Previous studies in adolescents were not adequately powered to accurately disentangle genetic and environmental influences on smoking initiation (SI) across adolescence. METHODS: Mega-analysis of pooled genetically informative data on SI was performed, with structural equation modeling, to test equality of prevalence and correlations across cultural backgrounds, and to estimate the significance and effect size of genetic and environmental effects according to the classical twin study, in adolescent male and female twins from same-sex and opposite-sex twin pairs (N = 19 313 pairs) between ages 10 and 19, with 76 358 longitudinal assessments between 1983 and 2007, from 11 population-based twin samples from the United States, Europe, and Australia. RESULTS: Although prevalences differed between samples, twin correlations did not, suggesting similar etiology of SI across developed countries. The estimate of additive genetic contributions to liability of SI increased from approximately 15% to 45% from ages 13 to 19. Correspondingly, shared environmental factors accounted for a substantial proportion of variance in liability to SI at age 13 (70%) and gradually less by age 19 (40%). CONCLUSIONS: Both additive genetic and shared environmental factors significantly contribute to variance in SI throughout adolescence. The present study, the largest genetic epidemiological study on SI to date, found consistent results across 11 studies for the etiology of SI. Environmental factors, especially those shared by siblings in a family, primarily influence SI variance in early adolescence, while an increasing role of genetic factors is seen at later ages, which has important implications for prevention strategies. IMPLICATIONS: This is the first study to find evidence of genetic factors in liability to SI at ages as young as 12. It also shows the strongest evidence to date for decay of effects of the shared environment from early adolescence to young adulthood. We found remarkable consistency of twin correlations across studies reflecting similar etiology of liability to initiate smoking across different cultures and time periods. Thus familial factors strongly contribute to individual differences in who starts to smoke with a gradual increase in the impact of genetic factors and a corresponding decrease in that of the shared environment.

Implant design influences patient outcome after total knee arthroplasty: a prospective double-blind randomised controlled trial.

Total knee arthroplasty (TKA) is an established and successful procedure. However, the design of prostheses continues to be modified in an attempt to optimise the functional outcome of the patient. The aim of this study was to determine if patient outcome after TKA was influenced by the design of the prosthesis used. A total of 212 patients (mean age 69; 43 to 92; 131 female (62%), 81 male (32%)) were enrolled in a single centre double-blind trial and randomised to receive either a Kinemax (group 1) or a Triathlon (group 2) TKA. Patients were assessed pre-operatively, at six weeks, six months, one year and three years after surgery. The outcome assessments used were the Oxford Knee Score; range of movement; pain numerical rating scales; lower limb power output; timed functional assessment battery and a satisfaction survey. Data were assessed incorporating change over all assessment time points, using repeated measures analysis of variance longitudinal mixed models. Implant group 2 showed a significantly greater range of movement (p = 0.009), greater lower limb power output (p = 0.026) and reduced report of 'worst daily pain' (p = 0.003) over the three years of follow-up. Differences in Oxford Knee Score (p = 0.09), report of 'average daily pain' (p = 0.57) and timed functional performance tasks (p = 0.23) did not reach statistical significance. Satisfaction with outcome was significantly better in group 2 (p = 0.001). These results suggest that patient outcome after TKA can be influenced by the prosthesis used.

Assessing treatment outcomes using a single question: the net promoter score.

Satisfaction with care is important to both patients and to those who pay for it. The Net Promoter Score (NPS), widely used in the service industries, has been introduced into the NHS as the 'friends and family test'; an overarching measure of patient satisfaction. It assesses the likelihood of the patient recommending the healthcare received to another, and is seen as a discriminator of healthcare performance. We prospectively assessed 6186 individuals undergoing primary lower limb joint replacement at a single university hospital to determine the Net Promoter Score for joint replacements and to evaluate which factors contributed to the response. Achieving pain relief (odds ratio (OR) 2.13, confidence interval (CI) 1.83 to 2.49), the meeting of pre-operative expectation (OR 2.57, CI 2.24 to 2.97), and the hospital experience (OR 2.33, CI 2.03 to 2.68) are the domains that explain whether a patient would recommend joint replacement services. These three factors, combined with the type of surgery undertaken (OR 2.31, CI 1.68 to 3.17), drove a predictive model that was able to explain 95% of the variation in the patient's recommendation response. Though intuitively similar, this 'recommendation' metric was found to be materially different to satisfaction responses. The difference between THR (NPS 71) and TKR (NPS 49) suggests that no overarching score for a department should be used without an adjustment for case mix. However, the Net Promoter Score does measure a further important dimension to our existing metrics: the patient experience of healthcare delivery.

El diagnóstico etiopatogénico en ortopedia funcional de los maxilares / Etiopathogenic diagnosis in functional maxillary orthopedics

La ortopedia funcional de los maxilares es una especialidad odontológica que trata los problemas funcionales, morfológicos y estéticos del complejo orofacial del paciente en crecimiento. En este contexto, la ortopedia funcional se distingue por su especial interés por la investigación de las causas y posteriores acontecimientos que en el transcurso de un período de tiempo provocan la manifestación clínica de una disgnacia; esta elaboración hipotética se denomina diagnóstico etiopatogénico. A través de una serie de casos clínicos se ejemplifica este proceso de diagnóstico, involucrando antecedentes hereditarios, trauma perinatal, alteraciones posturales, trastornos funcionales deglutorios, respiratorios, fonatorios y masticatorios, así como la biotipología facial. La elaboración de una hipótesis fundamentada que nos permita explicar las causas y acontecimientos que plasmaron el estado actual de nuestro paciente, nos impulsa a investigar, indagar, reflexionar y, finalmente, arribar a un conocimiento más amplio y profundo del mismo. Finalmente, el conocimiento de las posibles causas de la disgnacia nos conduce naturalmente hacia un diseño terapéutico integral.

Muscle 'regenerative potential' determinesphysical recovery following total knee replacement.

OBJECTIVES: Lower limb muscle power is thought to influence outcome following total knee replacement (TKR). Post-operative deficits in muscle strength are commonly reported, although not explained. We hypothesised that post-operative recovery of lower limb muscle power would be influenced by the number of satellite cells in the quadriceps muscle at time of surgery. METHODS: Biopsies were obtained from 29 patients undergoing TKR. Power output was assessed pre-operatively and at six and 26 weeks post-operatively with a Leg Extensor Power Rig and data were scaled for body weight. Satellite cell content was assessed in two separate analyses, the first cohort (n = 18) using immunohistochemistry and the second (n = 11) by a new quantitative polymerase chain reaction (q-PCR) protocol for Pax-7 (generic satellite cell marker) and Neural Cell Adhesion Molecule (NCAM; marker of activated cells). RESULTS: A significant improvement in power output was observed post-operatively with a mean improvement of 19.7 W (95% confidence interval (CI) 14.43 to 30.07; p < 0.001) in the first cohort and 27.5 W (95% CI 13.2 to 41.9; p = 0.002) in the second. A strong correlation was noted between satellite cell number (immunohistochemistry) and improvement in patient power output (r = 0.64, p = 0.008). Strong correlation was also observed between the expression of Pax-7 and power output (r = 0.79, p = 0.004), and the expression of NCAM and power output (r = 0.84, p = 0.001). The generic marker explained 58% of the variation in power output, and the marker of activated cells 67%. CONCLUSIONS: Muscle satellite cell content may determine improvement in lower limb power generation (and thus function) following TKR.

Eating patterns and leisure-time exercise among active duty military personnel: comparison to the Healthy People objectives.

OBJECTIVE: To assess whether active duty military personnel meet Healthy People 2010 objectives for physical activity and fruit, vegetable, and whole-grain intake; the relationship of select demographic characteristics, lifestyle factors (eg, smoking), and eating patterns (eg, frequency and location of meals) on achieving diet and exercise-related Healthy People 2010 objectives; and the relationship of eating patterns to self-reported weight gain. METHODS: Secondary data from 15,747 participants in the 2005 Department of Defense Health Related Behaviors Survey was analyzed. RESULTS: More than 57% of respondents met the Healthy People 2010 guidelines for moderate or vigorous leisure exercise but only 3% reported eating fruit (once), vegetables (3 times), and whole grains (3 times) daily. Individuals who reported gaining weight during the previous year were more likely to skip breakfast and eat at, or from, a restaurant ≥2 times per week compared with those who did not gain weight (P<0.001). Regression analysis indicated that women were more likely to eat fruits (odds ratio [OR] 1.25) and vegetables (OR 1.20) and less likely than men to eat whole grains (OR 0.76) or engage in moderate or vigorous exercise (OR 0.71). Military personnel who skipped breakfast ≥2 times per week (OR 0.45) or ate at a restaurant/takeout food (OR 0.54) ≥2 times per week were significantly less likely to meet Healthy People 2010 guidelines for food intake (defined as achieving a daily intake of one or more fruits, three or more vegetables, and three or more servings of whole grains) and exercise (OR 0.88 and 0.82, respectively). CONCLUSIONS: Although the majority of military personnel met guidelines for physical activity, their intake of fruits, vegetables, and whole grains was suboptimal. Skipping breakfast and eating at, or from, restaurants were risk factors for poor nutrient intake and associated with weight gain. These data suggest that skipping breakfast and eating out deter achieving Healthy People 2010 objectives and provide targets for military programs to promote achieving these objectives.

What determines patient satisfaction with surgery? A prospective cohort study of 4709 patients following total joint replacement.

OBJECTIVES: To investigate the factors which influence patient satisfaction with surgical services and to explore the relationship between overall satisfaction, satisfaction with specific facets of outcome and measured clinical outcomes (patient reported outcome measures (PROMs)). DESIGN: Prospective cohort study. SETTING: Single National Health Service (NHS) teaching hospital. PARTICIPANTS: 4709 individuals undergoing primary lower limb joint replacement over a 4-year period (January 2006-December 2010). MAIN OUTCOME MEASURES: Overall patient satisfaction, clinical outcomes as measured by PROMs (Oxford Hip or Knee Score, SF-12), satisfaction with five specific aspects of surgical outcome, attitudes towards further surgery, length of hospital stay. RESULTS: Overall patient satisfaction was predicted by: (1) meeting preoperative expectations (OR 2.62 (95% CI 2.24 to 3.07)), (2) satisfaction with pain relief (2.40 (2.00 to 2.87)), (3) satisfaction with the hospital experience (1.7 (1.45 to 1.91)), (4) 12 months (1.08 (1.05 to 1.10)) and (5) preoperative (0.95 (0.93 to 0.97)) Oxford scores. These five factors contributed to a model able to correctly predict 97% of the variation in overall patient satisfaction response. The factors having greatest effect were the degree to which patient expectations were met and satisfaction with pain relief; the Oxford scores carried little weight in the algorithm. Various factors previously reported to influence clinical outcomes such as age, gender, comorbidities and length of postoperative hospital stay did not help explain variation in overall patient satisfaction. CONCLUSIONS: Three factors broadly determine the patient's overall satisfaction following lower limb joint arthroplasty; meeting preoperative expectations, achieving satisfactory pain relief, and a satisfactory hospital experience. Pain relief and expectations are managed by clinical teams; however, a fractured access to surgical services impacts on the patient's hospital experience which may reduce overall satisfaction. In the absence of complications, how we deliver healthcare may be of key importance along with the specifics of what we deliver, which has clear implications for units providing surgical services.

Predicting the cost-effectiveness of total hip and knee replacement: a health economic analysis.

The aim of this study was to perform a cost-utility analysis of total hip (THR) and knee replacement (TKR). Arthritis is a disabling condition that leads to long-term deterioration in quality of life. Total joint replacement, despite being one of the greatest advances in medicine of the modern era, has recently come under scrutiny. The National Health Service (NHS) has competing demands, and resource allocation is challenging in times of economic restraint. Patients who underwent THR (n = 348) or TKR (n = 323) between January and July 2010 in one Scottish region were entered into a prospective arthroplasty database. A health-utility score was derived from the EuroQol (EQ-5D) score pre-operatively and at one year, and was combined with individual life expectancy to derive the quality-adjusted life years (QALYs) gained. Two-way analysis of variance was used to compare QALYs gained between procedures, while controlling for baseline differences. The number of QALYs gained was higher after THR than after TKR (6.5 vs 4.0 years, p < 0.001). The cost per QALY for THR was £1372 compared with £2101 for TKR. The predictors of an increase in QALYs gained were poorer health before surgery (p < 0.001) and younger age (p < 0.001). General health (EQ-5D VAS) showed greater improvement after THR than after TKR (p < 0.001). This study provides up-to-date cost-effectiveness data for total joint replacement. THR and TKR are extremely effective both clinically and in terms of cost effectiveness, with costs that compare favourably to those of other medical interventions.

Is patient reporting of physical function accurate following total knee replacement?

The aim of this study was to determine the association between the Oxford knee score (OKS) and direct assessment of outcome, and to examine how this relationship varied at different time-points following total knee replacement (TKR). Prospective data consisting of the OKS, numerical rating scales for 'worst pain' and 'perceived mean daily pain', timed functional assessments (chair rising, stairs and walking ability), goniometry and lower limb power were recorded for 183 patients pre-operatively and at six, 26 and 52 weeks post-operatively. The OKS was influenced primarily by the patient's level of pain rather than objective functional assessments. The relationship between report of outcome and direct assessment changed over time: R2 = 35% pre-operatively, 44% at six weeks, 57% at 26 weeks and 62% at 52 weeks. The relationship between assessment of performance and report of performance improved as the patient's report of pain diminished, suggesting that patients' reporting of functional outcome after TKR is influenced more by their pain level than their ability to accomplish tasks.

A prospective randomised double-blind study of functional outcome and range of flexion following total knee replacement with the NexGen standard and high flexion components.

Modifications in the design of knee replacements have been proposed in order to maximise flexion. We performed a prospective double-blind randomised controlled trial to compare the functional outcome, including maximum knee flexion, in patients receiving either a standard or a high flexion version of the NexGen legacy posterior stabilised total knee replacement. A total of 56 patients, half of whom received each design, were assessed pre-operatively and at one year after operation using knee scores and analysis of range of movement using electrogoniometry. For both implant designs there was a significant improvement in the function component of the knee scores (p < 0.001) and the maximum range of flexion when walking on the level, ascending and descending a slope or stairs (all p < 0.001), squatting (p = 0.020) and stepping into a bath (p = 0.024). There was no significant difference in outcome, including the maximum knee flexion, between patients receiving the standard and high flexion designs of this implant.

Cyclic pneumatic soft-tissue compression accelerates the union of distal radial osteotomies in an ovine model.

The aim of this randomised, controlled in vivo study in an ovine model was to investigate the effect of cyclic pneumatic pressure on fracture healing. We performed a transverse osteotomy of the right radius in 37 sheep. They were randomised to a control group or a treatment group where they received cyclic loading of the osteotomy by the application of a pressure cuff around the muscles of the proximal forelimb. Sheep from both groups were killed at four or six weeks. Radiography, ultrasonography, biomechanical testing and histomorphometry were used to assess the differences between the groups. The area of periosteal callus, peak torsional strength, fracture stiffness, energy absorbed over the first 10 degrees of torsion and histomorphometric analysis all showed that the osteotomies treated with the cyclic pneumatic pressure at four weeks were not significantly different from the control osteotomies at six weeks.

Recovery of knee function following fracture of the tibial plateau.

We assessed the functional outcome following fracture of the tibial plateau in 63 consecutive patients. Fifty-one patients were treated by internal fixation, five by combined internal and external fixation and seven non-operatively. Measurements of joint movement and muscle function were made using a muscle dynamometer at three, six and 12 months following injury. Thirteen patients (21%) had a residual flexion contracture at one year. Only nine (14%) patients achieved normal quadriceps muscle strength at 12 months, while 19 (30%) achieved normal hamstring muscle strength. Recovery was significantly slower in patients older than 40 years of age. We conclude that there is significant impairment of movement and muscle function after fracture of the tibial plateau and that the majority of patients have not fully recovered one year after injury.

Randomized trial of buffered versus plain lidocaine for local anaesthesia in open carpal tunnel decompression.

We performed a randomized double-blind case-control study in 64 consecutive patients undergoing open carpal tunnel decompression under local anaesthetic to assess the pain experienced on injection of plain lidocaine (pH 6.4) compared with lidocaine buffered with sodium bicarbonate (pH 7.4). The results showed no statistical difference in the pain scores reported by patients. The mean pain scores for all patients were low, and most patients reported that they were "not at all anxious" about receiving a similar injection in the future.

Survival analysis is a better estimate of recurrent disc herniation.

Studies on recurrent disc herniation quote rates of recurrence without regard to the times of recurrence and the influence of longer follow-up. Our objective was to assess the use of survival analysis to measure the rate of revision after lumbar microdiscectomy. We undertook a retrospective analysis of the hospital records of 993 patients who underwent lumbar microdiscectomy over a period of ten years. After calculating the overall rate of revision for the mean length of follow-up, we carried out a survival analysis using the life-table method. During the study period 49 patients had a revision microdiscectomy. This gave an overall rate of revision of 4.9% at a mean follow-up of 5.25 years. Using survival analysis, the rate of revision was 7.9% at a follow-up of ten years when the number at risk was 84. Survival analysis gives a more accurate estimation of the true rate of recurrence for patients undergoing lumbar microdiscectomy. The method allows better comparison between different interventions for disc herniation.

The association of eating behavior with risk for morbidity in older women.

BACKGROUND: Although an influence of eating behavior on dietary intake and physiology has been documented in several studies, the extent to which eating behavior influences long-term health is uncertain. METHODS: Current dietary restraint, disinhibition, and hunger were assessed using the Eating Inventory in 1252 nonsmoking women aged 55 to 65 years. In addition, subjects reported the presence or absence of 22 specific morbidities, along with general demographic information. Logistic regression was used to examine associations between eating behavior scores and morbidity, adjusting for age, prior smoking status, hormone replacement therapy, education level, and body mass index (BMI). RESULTS: In adjusted models excluding BMI, higher disinhibition scores were associated with small increased risks for hypercholesterolemia (odds ratio [OR] 1.04, p =.045), leg cramps (OR 1.05, p =.044), indigestion (OR 1.06, p =.020), and cataract (OR 1.09, p =.036), and a decreased risk of eczema (OR 0.91, p =.008). In addition, higher hunger scores were associated with increased risk of eczema (OR 1.09, p =.026). However, after adjusting for confounding variables plus BMI, higher disinhibition scores were associated with increased risks for low back pain (OR 1.06, p =.031) and constipation (OR 1.10, p =.004), and associations of disinhibition and hunger with eczema were unchanged (OR 0.90, p =.008 and OR 1.09, p =.024, respectively). Dietary restraint was not associated with morbidity in any model. CONCLUSIONS: Higher disinhibition and hunger scores were associated with small alterations in reported morbidity risk in a large population of nonsmoking older women. Although our cross-sectional study design makes the directionality of these relationships unclear, our results suggest at most a relatively minor independent influence of eating behavior constructs on long-term health.