Temporal trends in primary total hip and knee arthroplasty surgery: results from a UK regional joint register, 1991-2004.

INTRODUCTION: The aim of this study was to evaluate temporal trends in the prevalence of primary total hip and knee replacements (THRs and TKRs) throughout the Trent region from 1991 to 2004. PATIENTS AND METHODS: The Trent Regional Arthroplasty Study records details of primary THR and TKR prospectively and data from the register were examined. Age and gender population data were provided by the Office for National Statistics. RESULTS: A total of 26,281 THRs and 23,606 TKRs were recorded during this period. Analysis showed that females had an increased incidence rate ratio (IRR) for both primary THR (IRR = 1.29; 95% CI 1.26-1.33; P < 0.001) and TKR (IRR = 1.17; 95% CI 1.14-1.20; P < 0.001). Patients aged 74-85 years had the largest IRR for both primary THR (IRR = 6.7; 95% CI 6.4-7.0; P < 0.001) and TKR (IRR = 15.3; 95% CI 14.4-16.3; P < 0.001). CONCLUSIONS: The prevalence of primary TKR increased significantly over time whereas THR remained steady in the Trent region between 1991 and 2004.

A new musculoskeletal curriculum: has it made a difference?

This study assessed whether undergraduate performance improved following the introduction in 2006 of a musculoskeletal teaching programme lasting for seven weeks. Different methods were used to deliver knowledge and skills in trauma and orthopaedic surgery, rheumatology and allied specialties. The programme combined four main elements: traditional firm-based teaching, weekly plenary sessions, a task-based workbook and additional specialist clinics. The block of 139 students who attended in its first year were assessed using a multiple choice question examination just before their final examinations in 2008. They showed a 6% improvement in performance over a control group of 130 students assessed in 2005 before the programme had commenced. There was no difference in performance between the students assessed in 2005 and a second group of 46 students from 2008 who did not attend the new teaching programme. Performance was improved by providing more focused musculoskeletal training using available resources, as well as increasing the length of the programme.

A study of grip endurance and strengh in different elbow positions.

BACKGROUND: The aim of our study was twofold. The first was to investigate the optimum position of the elbow while measuring grip endurance. The second was to investigate the optimum position of the elbow while measuring peak grip strength. The American Society of Hand Therapists advocate estimation of grip strength with the elbow flexed at 90 degrees with the subject in the sitting position . As far as we are aware, there have been no reports in English literature regarding studies done to evaluate the position of the elbow while measuring grip endurance. MATERIALS AND METHODS: A total of 45 healthy adults (16 males, 29 females) participated in this study. A computerised handgrip analyser was used to measure the peak strength in the non-dominant hand, followed by measurement of the grip endurance. These measurements were conducted in 90 degrees of flexion and full extension of the elbow for each participant. RESULTS: Mean endurance in flexion was 71.0 N (SD 22.9) and in extension was 68.7 N (SD 27.4). Mean peak grip strength in flexion was 262.8 N (SD 73.1) and in extension was 264.1 N (SD 82.0). T test analysis showed no statistical significance for elbow positions for grip endurance (P = 0.67) and peak gip strength (P = 0.93). CONCLUSION: Practical implications from this study are that grip endurance training can be undertaken with the elbow in 90 degrees of flexion or full extension.

A 15-year follow-up study of 4606 primary total knee replacements.

This is a 15-year follow-up observational study of 4390 patients with 4606 primary total knee replacements (TKRs) implanted in the Trent health region between 1990 and 1992. The operations were performed in 21 hospitals, including both district general and teaching hospitals, with 77 different surgeons as named consultant. The main objective was to analyse the survival of the patients and of the prostheses, and to evaluate what impact different variables have on survival. In addition, the 1480 patients (33.7%) (1556 TKRs) alive at 15 years following operation were sent a self-administered questionnaire which examined their level of satisfaction, of pain, and their quality of life at 15 years. Completed responses were received from 912 TKRs (58.6%). Three survival curves were constructed: a best-case scenario based on the patients entered into the life tables, another included failures not reported in the revision database, and a third worst-case scenario based on all patients lost to follow-up presumed to have had a failed primary TKR. In the best-case scenario survival at 15 years was 92.2%, and in the worst-case scenario was 81.1%. Survival was significantly increased in women and older patients (Mantel-Cox log-rank test, p < 0.005 and p < 0.001, respectively). Revision as a result of infection was required in 40 TKRs (18.8%) representing 0.87% of the original cohort. The limited information available from the questionnaire indicated that satisfaction was less frequent among men, patients with osteoarthritis and those who required revision (chi-squared test, p < 0.05, p < 0.05 and p < 0.0001, respectively). With regard to pain, older patients, females and patients who still had their primary replacement in place at 15 years, reported the least pain (chi-squared test for trends, p < 0.0005, p < 0.005 and p < 0.0001, respectively). The reported quality of life was not affected by any variable.

What impact have NICE guidelines had on the trends of hip arthroplasty since their publication? The results from the Trent Regional Arthroplasty Study between 1990 and 2005.

The National Institute for Clinical Excellence (NICE) published the guidelines on the selection of prostheses for primary hip replacement in 2000. They supported the use of cemented hip prostheses to the exclusion of uncemented and hybrid implants. The information from the Trent (and Wales) Regional Arthroplasty Study has been examined to identify retrospectively the types of hip prostheses used between 1990 and 2005, and to assess the impact that the guidelines have had on orthopaedic practice. The results show that the publication of the NICE guidelines has had little impact on clinical practice, with the use of uncemented prostheses increasing from 6.7% (137) in 2001 to 19.2% (632) in 2005. The use of hybrid prostheses has more than doubled from 8.8% (181) to 22% (722) of all hips implanted in the same period. The recommendations made by NICE are not being followed, which calls into question their value.

Significance of hip rotation on measurement of 'Tip Apex Distance' during fixation of extracapsular proximal femoral fractures.

UNLABELLED: The Tip Apex Distance (TAD) is defined as the sum of the distance, in millimetres, from the tip of the lag screw to the apex of the femoral head, as measured on an antero-posterior radiograph and lateral radiograph, after correction has been made for magnification. The relationship between the degree of rotation of the hip joint and its implication on measuring TAD during fixation of a proximal femoral fracture was studied. This relationship has not been previously explored in the English literature. This study involved radiographs of a lag screw placed in a synthetic femur specimen taken in neutral and varying degrees of rotation and adduction/abduction. The lag screw was placed anteriorly in the femoral head. Measurements were taken for each radiograph after correction for magnification. RESULTS: Statistical analysis between measurements showed statistically significant differences (P<0.05) of TAD in AP and lateral (abduction and adduction) views. A graph to show the relationship between hip rotation and TAD was conducted and demonstrates a linear correlation. CONCLUSION: If an anteriorly placed hip screw is not seen to be breaching the articular surface on a view taken in internal rotation, the screw is definitely not in the joint. Beware of a hip screw appearing very close to the joint surface on a view taken in external rotation or abduction as it could be within the joint. The converse may apply to a posteriorly placed screw.

Outcome of Charnley total hip replacement across a single health region in England. The results at ten years from a regional arthroplasty register.

Using the Trent regional arthroplasty register, we analysed the survival at ten years of 1198 consecutive Charnley total hip replacements carried out across a single health region of the United Kingdom in 1990. At ten years, information regarding outcome was available for 1001 hips (83.6%). The crude revision rate was 6.2% (62 of 1001) and the cumulative survival rate with revision of the components as an end-point was 93.1%. At five years, a review of this series of patients identified gross radiological failure in 25 total hip replacements which had previously been unrecognised. At ten years the outcome was known for 18 of these 25 patients (72%), of whom 13 had not undergone revision. This is the first study to assess the survival at ten years for the primary Charnley total hip replacement performed in a broad cross-section of hospitals in the United Kingdom, as opposed to specialist centres. Our results highlight the importance of the arthroplasty register in identifying the long-term outcome of hip prostheses.

Comparison of accuracy of lag screw placement in cephalocondylic nails and sliding hip screw plate fixation for extracapsular fractures of the neck of femur.

This study compared the accuracy of lag screw placement between extracapsular femoral fractures fixed with sliding hip screw plate systems and those fixed with cephalocondylic nails. It involved 75 retrospective radiographs of fractures fixed with either a cephalocondylic nail (32) or a sliding hip screw plate system (43). Postoperative anteroposterior and lateral radiographs of the hip were scanned using a digital X-ray scanner and measured using computer software. Measurements were conducted by two independent observers, and the radiographs were calibrated to correct for magnification. Accuracy of lag screw placement was determined by "tip apex distance," described by Baumgaertner et al., and by the ratio method described by Parker. The mean tip apex distance was 24.0 mm in sliding hip screw plate systems and 21.1 mm in cephalocondylic nails. This was found to be statistically significant. Lag screw placement through cephalocondylic nails is more accurate and therefore has less chance of cut-out compared with sliding hip screw plate systems. There was no statistically significant difference using Parker's ratio method because this method quantifies the direction of the screw rather than the depth of penetration.

Primary hip replacement in young osteoarthritic patients current practices in one UK region.

Approximately 10% of primary hip replacements performed each year for osteoarthritis are in patients aged 55 or younger. These patients have a longer life expectancy and a higher activity level than an older cohort, which may translate to higher revision rates. We utilized a regional hip register (Trent and Welsh Arthroplasty Audit Group (TWAAG)) to review current surgical practice in this age group. From 01/01/2000 31/12/2002, we were notified of 7,678 primary THRs for osteoarthritis. Of these 911 (11.7%) were performed on patients aged 55 or less. Age, gender, grade of lead operating surgeon, type of femoral and acetabular prostheses implanted, fixation method, femoral head size and bearing surfaces were recorded. There were 434 males and 477 females, with an age range of 16-55. Thirty-five femoral and 33 acetabular components were identified: 61.7% of femoral prostheses were cemented; 67.4 % of acetabular prostheses were uncemented. Fifty per cent of implants had a metal/UHMWPE bearing. Other bearing surfaces comprised ceramic/UHMWPE 28.7%, metal/metal resurfacing 13.8% and ceramic/ceramic 7.5%. Consultants performed 84.5% of procedures. The study indicates that there does not appear to be a clear consensus as to component choice or optimum fixation method in the younger patient. (Hip International 2005; 15: 159-65) KEY WORDS: Hip replacement, Arthroplasty, Young patient, Osteoarthritis.

A year's trauma admissions and the effect of the weather.

PURPOSE OF THE STUDY: To study the admissions to a busy trauma unit on a day-by-day basis over a 1 year period, and to look for any correlation with local weather variation or temporal factors (day of the week, weekends/school holidays, etc.). METHOD: Admissions data for the Trauma Unit at the Leicester Royal Infirmary was collected from an administrative database and ward records for the calendar year of 1998. Admissions were split into four groups: all admissions, adult admissions, admissions for proximal femoral fractures (neck of femur (NOF)) and paediatric admissions. Weather information for the local area was obtained from the Meteorological Office. Details of school holidays were obtained from the local Education Department. The above variables were examined using Poisson regression analysis for their potential importance in explaining day-to-day variation in admission rates for the four groups. RESULTS: For adult and NOF admissions, none of the weather factors appeared to explain variation in incidence, only day of the week appears to be important, with the earlier part of the week yielding a highly statistically significant increase in the relative incidence of trauma admissions. For both paediatric and total admissions, a number of factors appear important, including maximum and minimum temperatures, hours of sunshine, day of the week and month of the year. Daily rainfall, significant weather and whether the day was a school day or school holiday did not appear to be important on univariate analysis. CONCLUSION: Trauma admissions are related to both weather and temporal factors. This may have implications both in terms of prevention and in planning of care provision in trauma units.

Lower limb arthroplasty complicated by deep venous thrombosis. Prevalence and subjective outcome.

The aim of this study was to determine the prevalence of deep venous thrombosis (DVT) following lower limb arthroplasty and to assess whether this adversely affected satisfaction, relief from pain, or the level of mobility as perceived by patients. Six hundred and ten consecutive recipients of primary total hip replacement (THR) or total knee replacement (TKR) underwent routine post-operative venography. The functional outcome had already been assessed at one year by using the Regional Arthroplasty Database questionnaire, the results of which were correlated to venographic records. The combined prevalence of DVT after THR and TKR in the patients, who did not receive chemical thromboprophylaxis, was 46.4%. Thrombus was identified in 57.6% of those with a TKR and in 33.5% of patients with a THR. Proximal thrombus was found in 11.0% of TKRs and in 14.8% of THRs. One year after surgery, patients who had a DVT established by venography did not report higher levels of immobility (p = 0.07), discomfort (p = 0.12) or dissatisfaction (p = 0.23) when compared to those with patent venous systems. This suggests that the prevalence of DVT following TKR/THR without chemical thromboprophylaxis is high and these findings are consistent with the literature. However, patients did not perceive thrombosis to compromise their overall outcome. This challenges the belief that DVT is associated with morbidity and calls for further comprehensive research in this area. The low morbidity of the lower limb associated with DVT in these patients does not support the use of chemical thromboprophylaxis.

Improving the quality of patient care: patient satisfaction with a nurse-led fracture clinic service.

A prospective study was conducted to assess nurse-led follow-up of patients with fracture.

Measurement of protein synthesis and degradation in C2C2) myoblasts using extracts of muscle from hormone treated bovine.

A detailed methodology is described for determination of treatment effects on muscle cell protein synthesis and muscle cell protein degradation in a cell culture system. C(2)C(22) mouse myoblasts were treated with growth media containing muscle extracts from bovine treated with different pharmaceutical agents. Radiolabeled amino acids were added to the growth media to determine treatment effects on protein synthesis and protein degradation. Percent protein synthesis was calculated by measuring amino acid uptake as a percentage over internal control. Percent protein degradation was measured using a pulse chase technique. These procedures will allow researchers to determine treatment effects on overall protein synthesis and degradation in vitro in a relatively short amount of time without excessive costs. A second benefit is that animals do not have to be fed radiolabeled feedstuffs. These procedures are not intended to elucidate the mechanisms behind pharmaceutical enhancement of muscle cell protein synthesis or protein degradation.

Conservative versus operative treatment for displaced ankle fractures in patients over 55 years of age. A prospective, randomised study.

Forty-seven patients over the age of 55 years with a displaced fracture of the ankle were entered into a prospective, randomised study in order to compare open reduction and internal fixation with closed treatment in a plaster cast; 36 were reviewed after a mean of 27 months. The outcome was assessed clinically, radiologically and functionally using the Olerud score. The results showed that anatomical reduction was significantly less reliable (p = 0.03) and loss of reduction significantly more common (p = 0.001) in the group with closed treatment. Those managed by open reduction and internal fixation had a significantly higher functional outcome score (p = 0.03) and a significantly better range of movement of the ankle (p = 0.044) at review.

Treatment for displaced intracapsular fracture of the proximal femur. A prospective, randomised trial in patients aged 65 to 79 years.

We performed a prospective, randomised trial comparing three treatments for displaced intracapsular fractures of the hip in 280 patients aged 65 to 79 years. The mean patient survival was significantly higher in the group undergoing reduction and internal fixation (79 months) compared with that with a cemented Thompson hemiarthroplasty or a cemented Monk bipolar hemiarthroplasty (61 months and 68 months, respectively). After three years, 32 of 93 patients (34.4%) who had undergone fixation had local complications, necessitating further intervention in 28 (30%). There were no significant differences in the functional outcome in survivors, who were reviewed annually to five years. Either reduction and internal fixation or cemented hemiarthroplasty may be offered as alternative treatments for a displaced intracapsular fracture in a mobile and mentally competent patient under the age of 80 years. The choice of procedure by the patient and the surgeon should be determined by the realisation that the use of internal fixation is associated with a 30% risk of failure requiring further surgery. If this is accepted, however, hemiarthroplasty is avoided, which, in our study has a significantly shorter mean survival time. The use of a bipolar prosthesis has no significant advantage.

The Trent regional arthroplasty study. Experiences with a hip register.

We have assessed the usefulness of a regional hip register in the assessment of the outcome of primary total hip replacement (THR). Over 97% of THRs performed in the Trent region in 1990 were captured onto the register and the inaccuracies recorded were less than 1.8%. In an independent assessment of 2111 patients five years after THR, 85.9% of those available for assessment responded, and 66.8% agreed to an assessment. The cost of this independent assessment at five years, utilising a regional hip register, was approximately l50 per implant. This is a reasonable outlay to identify problems early. Some form of registration and outcome assessment should be performed on a national level.

Revision hip arthroplasty activity in a single UK health region: an audit of 1265 cases.

Revision hip arthroplasty is an operation which is steadily increasing in number and can often be technically challenging. We have utilised a regional hip register (the Trent Regional Arthroplasty Study) to analyse the epidemiology of revision hip arthroplasties in a single UK health region. The study shows that of the large number (1265) of procedures performed over a 7-year period (1991-1997), the majority were performed by general orthopaedic surgeons, with 91 different surgeons performing the operation and only two surgeons performing more than 20 procedures per year. Of more than 100 prosthetic combinations used for the procedure, the Charnley prosthesis was the most common (38.3% of acetabular revisions and 37.5% of femoral revisions). The same component was also the most commonly explanted (43%). There was an even geographical spread across the region with revision hip arthroplasty being performed in all hospitals with an orthopaedic in-patient facility. Prospective audit of this large and varied cohort is necessary to determine differences in outcome (if any) between 'specialist' hip surgeons and general orthopaedic surgeons.