Harmonising measures of knee and hip osteoarthritis in population-based cohort studies: an international study.

OBJECTIVE: Population-based osteoarthritis (OA) cohorts provide vital data on risk factors and outcomes of OA, however the methods to define OA vary between cohorts. We aimed to provide recommendations for combining knee and hip OA data in extant and future population cohort studies, in order to facilitate informative individual participant level analyses. METHOD: International OA experts met to make recommendations on: 1) defining OA by X-ray and/or pain; 2) compare The National Health and Nutrition Examination Survey (NHANES)-type OA pain questions; 3) the comparability of the Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) scale to NHANES-type OA pain questions; 4) the best radiographic scoring method; 5) the usefulness of other OA outcome measures. Key issues were explored using new analyses in two population-based OA cohorts (Multicenter Osteoarthritis Study; MOST and Osteoarthritis Initiative OAI). RESULTS: OA should be defined by both symptoms and radiographs, with symptoms alone as a secondary definition. Kellgren and Lawrence (K/L) grade ≥2 should be used to define radiographic OA (ROA). The variable wording of pain questions can result in varying prevalence between 41.0% and 75.4%, however questions where the time anchor is similar have high sensitivity and specificity (91.2% and 89.9% respectively). A threshold of 3 on a 0-20 scale (95% CI 2.1, 3.9) in the WOMAC pain subscale demonstrated equivalence with the preferred NHANES-type question. CONCLUSION: This research provides recommendations, based on expert agreement, for harmonising and combining OA data in existing and future population-based cohorts.

Physical activity and osteoarthritis: a consensus study to harmonise self-reporting methods of physical activity across international cohorts.

Physical activity (PA) is increasingly recognised as an important factor within studies of osteoarthritis (OA). However, subjective methods used to assess PA are highly variable and have not been developed for use within studies of OA, which creates difficulties when comparing and interpreting PA data in OA research. The aim of this study was, therefore, to gain expert agreement on the appropriate methods to harmonise PA data among existing population cohorts to enable the investigation of the association of PA and OA. The definition of PA in an OA context and methods of harmonization were established via an international expert consensus meeting and modified Delphi exercise using a geographically diverse committee selected on the basis of individual expertise in physical activity, exercise medicine, and OA. Agreement was met for all aims of study: (1) The use of Metabolic Equivalent of Task (MET) minutes per week (MET-min/week) as a method for harmonising PA variables among cohorts; (2) The determination of methods for treating missing components of MET-min/week calculation; a value will be produced from comparable activities within a representative cohort; (3) Exclusion of the domain of occupation from total MET-min/week; (4) The need for a specific measure of joint loading of an activity in addition to intensity and time, in studies of diseases, such as OA. This study has developed a systematic method to classify and harmonise PA in existing OA cohorts. It also provides minimum requirements for future studies intending to include subjective PA measures.

Tennis injury data from The Championships, Wimbledon, from 2003 to 2012.

OBJECTIVE: The primary aims of this retrospective study were to describe the burden of injury presenting to the medical team and the changes in injury profile over 10 years (2003-2012) at The Championships, Wimbledon. Secondary aims included description of gender difference in rates, distribution and pathology of injuries. DESIGN: Retrospective observational cohort of player injury presentations over 10 years (2003-2012) at The Championships, Wimbledon. RESULTS: The overall rate of presentation of injury for all players over the 10-year period was 20.7 per 1000 sets played. Injury rates were lower for male players (17.7 injuries per 1000 sets played) than female players (23.4 injuries per 1000 sets played). There was variability in the numbers of injuries reported by men and women players over the 10-year period. CONCLUSIONS: The rates of presentation of injury at this Grand Slam tennis tournament varied between male and female players, and between years. More robust systems of data collection are required in professional tennis to enable more sophisticated injury data analysis between sexes, years and different playing surfaces.

Assessing risk factors for early hip osteoarthritis in activity-related hip pain: a Delphi study.

OBJECTIVE: Hip pain and injury as a result of activity can lead to the development of early hip osteoarthritis (OA) in susceptible individuals. Our understanding of the factors that increase susceptibility continues to evolve. The ability to clearly identify individuals (and cohorts) with activity-related hip pain who are at risk of early hip OA is currently lacking. The purpose of this study was to gain expert consensus on which key clinical measures might help predict the risk of early hip OA in individuals presenting with activity-related hip pain. The agreed measures would constitute a standardised approach to initial clinical assessment to help identify these individuals. METHODS: This Dephi study used online surveys to gain concordance of expert opinion in a structured process of 'rounds'. In this study, we asked 'What outcome measures are useful in predicting hip OA in activity-related hip pain?' The Delphi panel consisted of experts from sport and exercise medicine, orthopaedics, rheumatology, physiotherapy and OA research. RESULTS: The study identified key clinical measures in the history, examination and investigations (plain anteroposterior radiograph and femoroacetabular impingement views) that the panel agreed would be useful in predicting future risk of hip OA when assessing activity-related hip pain. The panel also agreed that certain investigations and tests (eg, MR angiography) did not currently have a role in routine assessment. There was a lack of consensus regarding the role of MRI, patient-reported outcome measures (PROMs) and certain biomechanical and functional assessments. CONCLUSIONS: We provide a standardised approach to the clinical assessment of patients with activity-related hip pain. Assessment measures rejected by the Delphi panel were newer, more expensive investigations that currently lack evidence. Assessment measures that did not reach consensus include MRI and PROMs. Their role remains ambiguous and would benefit from further research.

Consensus statement on epidemiological studies of medical conditions in tennis, April 2009.

BACKGROUND: The reported incidence, severity and nature of injuries sustained in tennis vary considerably between studies. While some of these variations can be explained by differences in sample populations and conditions, the main reasons are related to differences in definitions and methodologies employed in the studies. OBJECTIVE: This statement aims to review existing consensus statements for injury surveillance in other sports in order to establish definitions, methods and reporting procedures that are applicable to the specific requirements of tennis. DESIGN: The International Tennis Federation facilitated a meeting of 11 experts from seven countries representing a range of tennis stakeholders. Using a mixed methods consensus approach, key issues related to definitions, methodology and implementation were discussed and voted on by the group during a structured 1-day meeting. Following this meeting, two members of the group collaborated to produce a draft statement, based on the group discussions and voting outcomes. Three revisions were prepared and circulated for comment before the final consensus statement was produced. RESULTS: A definition of medical conditions (injuries and illnesses) that should be recorded in tennis epidemiological studies and criteria for recording the severity and nature of these conditions are proposed. Suggestions are made for recording players' baseline information together with recommendations on how medical conditions sustained during match play and training should be reported. CONCLUSIONS: The definitions and methodology proposed for recording injuries and illnesses sustained during tennis activities will lead to more consistent and comparable data being collected. The surveillance procedures presented here may also be applicable to other racket sports.

Metatarsal fractures and sports.

OBJECTIVES: Metatarsal fractures are commonly sustained during sport but little is written about metatarsal fractures in the athletic population. Demographics and definitive treatment in patients who sustained metatarsal fractures through sport were compared with an overall metatarsal fracture population. MATERIALS AND METHODS: We used a prospective cohort study from a teaching hospital fracture clinic. Eighteen months of data were coded from presentation with a metatarsal fracture. Demographics, metatarsal fracture, participating sport and treatment were recorded and analysed. RESULTS: 791 patients presented with metatarsal fractures in an 18 month period with 74 metatarsal fractures sustained through sport. In the overall cohort group, there were 443 females and 348 males with a mean age of 44 (age range 15-91) and in the athletic population there were 6 females and 68 males with a mean age of 26 (age range 15-62). The majority of the metatarsal fractures sustained from sport were from soccer (73%), with the fifth metatarsal being the most commonly fractured. The definitive treatment in both groups appears to be similar, where the mainstay of treatment is conservative with the use of cast or early mobilisation with an elasticated support stocking. CONCLUSION: In this cohort approximately 9% of metatarsal fractures were sustained through sport, with soccer being the most common sport. Following high profile injuries to metatarsals in soccer players, it has been suggested that the incidence of these fractures is rising. Thus, it is recommended that a detailed prospective study be undertaken to specifically study the incidence, aetiology and morbidity of metatarsal fractures in the athletic population.

Selecting outcome measures in sports medicine: a guide for practitioners using the example of anterior cruciate ligament rehabilitation.

Using examples from the field of anterior cruciate ligament rehabilitation, this review provides sports and health practitioners with a comprehensive, user-friendly, guide to selecting outcome measures for use with active populations. A series of questions are presented for consideration when selecting a measure: is the measure appropriate for the intended use? (appropriateness); is the measure acceptable to patients? (acceptability); is it feasible to use the measure? (feasibility); does the measure provide meaningful results? (interpretability); does the measure provide reproducible values? (reliability); does the measure assess what it is supposed to assess? (validity); can the measure detect change? (responsiveness); do substantial proportions of patients achieve the worst or best scores? (floor and ceiling effects); is the measure structured and scored correctly? (dimensionality and internal consistency); has the measure been tested with the types of patients with whom it will be used? (sample characteristics). Evaluation of the measure using these questions will assist practitioners in making their judgements.

Physical activity interventions in the workplace: the rationale and future direction for workplace wellness.

The developing and developed worlds are both facing an obesity epidemic with their workers getting bigger, or to be more specific, fatter. As demonstrated elsewhere in this issue, the individual and societal health and economic costs of obesity and physical inactivity are enormous. There is thus a need for regional, national and global action to combat the issues, with programmes broadly divisible into children and adolescents, the workforce, active aging, healthy aging and a broad cross-cutting agenda that focuses on the built environment.

Magnetic resonance imaging of the lumbar spine in asymptomatic professional fast bowlers in cricket.

Low back injuries account for the greatest loss of playing time for professional fast bowlers in cricket. Previous radiological studies have shown a high prevalence of degeneration of the lumbar discs and stress injuries of the pars interarticularis in elite junior fast bowlers. We have examined MRI appearance of the lumbar spines of 36 asymptomatic professional fast bowlers and 17 active control subjects. The fast bowlers had a relatively high prevalence of multi-level degeneration of the lumbar discs and a unique pattern of stress lesions of the pars interarticularis on the non-dominant side. The systems which have been used to classify the MR appearance of the lumbar discs and pars were found to be reliable. However, the relationship between the radiological findings, pain and dysfunction remains unclear.

Do non-steroidal anti-inflammatory drugs adversely affect stress fracture healing? A short review.

A literature search was performed to determine whether non-steroidal anti-inflammatory drugs (NSAIDs) adversely affect the healing of stress fractures. Evidence exists from laboratory studies and animal subjects that NSAIDs can affect fracture healing. This link has not been proved or disproved in human subjects, particularly for stress fractures. In view of the high usage of NSAIDs in treating musculoskeletal disorders, research is required to investigate whether the healing of stress fractures is affected by these drugs.

Comparing spondylolysis in cricketers and soccer players.

OBJECTIVE: To determine whether the location of spondylolysis in the lumbar spine of athletes differs with biomechanical factors. METHODS: Single photon emission computerised tomography and reverse gantry computerised tomography were used to investigate 42 cricketers and 28 soccer players with activity related low back pain. Sites of increased scintigraphic uptake in the posterior elements of the lumbar spine and complete or incomplete fracture in the pars interarticularis were compared for these two sports. RESULTS: Thirty seven (90.4%) cricketers and 23 (82.1%) soccer players studied had sites of increased uptake. In cricketers, these sites were on the left of the neural arch of 49 lumbar vertebrae and on the right of 33 vertebrae. In soccer players there was a significantly different proportion, with 17 sites on the left and 28 on the right (difference of 22.0%; 95% confidence interval (CI) 0.04 to 0.38). Lower lumbar levels showed increased scintigraphic uptake more frequently than did higher levels, although the trend was reversed at L3 and L4 in soccer. Forty spondylolyses were identified in the lumbar vertebrae of the cricketers and 35 spondylolyses in the soccer players. These comprised 26 complete and 14 incomplete fractures in the cricketers, and 25 complete and 10 incomplete fractures in the soccer players. Similar numbers of incomplete fractures were found either side of the neural arch in soccer players, but there were more incomplete fractures in the left pars (14) than in the right (2) in cricketers. The proportion of incomplete fractures either side of the neural arch was significantly different between cricket players and soccer players (difference of 37.5%; 95% CI 0.02 to 0.65). Most complete fractures were at L5 (66.7%) and more were found at L3 (15.7%) than L4 (6.9%). However, incomplete fractures were more evenly spread though the lower three lumbar levels with 41.7% at L5, 37.5% at L4, and 20.8% at L3. CONCLUSIONS: Fast bowling in cricket is associated with pars interarticularis bone stress response and with development of incomplete stress fractures that occur more frequently on the left than the right. Playing soccer is associated with a more symmetrical distribution of bone stress response, including stress fracturing. Within cricketers, unilateral spondylolyses tend to arise on the contralateral side to the bowling arm.

The value of combining single photon emission computerised tomography and computerised tomography in the investigation of spondylolysis.

The aim of this study was to assess the diagnostic value of combining single photon emission computerised tomography (SPECT) with reverse gantry computerised tomography (rg-CT) in the investigation of spondylolysis. Patient characteristics and imaging results in 118 patients, aged 8-44 years, with low back pain (LBP) were analysed. SPECT showed increased scintigraphic uptake in 80 patients, and spondylolysis was identified on rg-CT in 53. The Cohen Kappa ratio of 0.362 (95% CI: 0.198-0.526) suggests only fair agreement for the result of increased scintigraphic activity with the finding of spondylolysis on rg-CT. We conclude that these investigations give mutually exclusive information, which leads to four diagnostic categories. When there was increased scintigraphic activity on SPECT, 58.8% (95% CI: 48.0-69.5%) of patients had spondylolysis on rg-CT. With rest from provoking activities, these lesions may heal. We interpret the findings of increased scintigraphic activity, but no spondylolysis demonstrated on rg-CT as indicating a bone stress response. These also require rest from provoking activity to prevent a stress fracture developing. In this study, 84.2% (95% CI: 72.67-95.8%) of those patients without increased activity on SPECT had no spondylolysis identified on rg-CT. These patients may need further investigations such as magnetic resonance imaging (MRI) to diagnose pathology, which typically does not involve the posterior elements--but rest from sport may not be so important. There were five patients in our study, without increased scintigraphic activity, but in whom bilateral chronic-appearing (wide separation, smooth sclerotic bone margins) spondylolyses were identified at L5. These all were anticipated from previous plain radiographs or MRI. This group will almost certainly not heal, and if the spondylolyses are the cause of pain these vertebrae will need stabilisation by surgery if physiotherapy fails.

Is risk of fast bowling injury in cricketers greatest in those who bowl most? A cohort of young English fast bowlers.

OBJECTIVES: To determine whether young fast bowlers are exceeding directives limiting bowling and how incidence of fast bowling injury varies with amount of bowling. METHODS: A prospective cohort study of injuries sustained by 70 fast bowlers (mean (SD) age 15.3 (2.4) years) was undertaken. Bowlers were recruited from the Centres of Excellence of three "First Class" counties in England in January 1998. Details of injuries were collected by telephone questionnaire every six weeks for six months from each bowler. The number of balls bowled in matches and practices by each bowler was recorded. The cohort was divided into groups according to the number of balls bowled in the study period, and bowling injury incidences were calculated for each group. MAIN OUTCOME MEASURES: All injuries caused by bowling and interfering with bowling. RESULTS: Telephone follow up was achieved when planned on 97.9% of occasions. There were 23 bowling injuries reported in the study period that met the inclusion criteria. The overall incidence of bowling injury in the study period was 32.8 per 100 fast bowlers. The incidence of bowling injury for the 15 bowlers who bowled less than 1000 balls in the study period was 20.0 per 100 fast bowlers. The incidence for the 32 who bowled 1000-2000 balls was 37.5 per 100 fast bowlers. The incidence for the 14 who bowled 2000-3000 balls was 35.7 per 100. The incidence for the nine who bowled more than 3000 balls was 33.3 per 100. CONCLUSIONS: The expected increased incidence of bowling injury in young fast bowlers who bowl most was not observed, although more than 12% exceeded the recommended limit.

Results of inguinal canal repair in athletes with sports hernia.

AIMS: To evaluate the role of surgical exploration and repair of the inguinal canal in athletes suspected of having a sports hernia. METHODS: Thirty-five (34 males, 1 female) athletes with a suspected sports hernia underwent surgical exploration and inguinal hernia repair. After six months, all athletes were sent questionnaires to assess any improvement in analogue pain scores, return to sport, recurrence of symptoms and the overall result of surgery. RESULTS: Operative findings revealed a tear in the external oblique aponeurosis with or without a significant posterior bulge (n=20), a lone significant posterior bulge (n=10), a tear in the conjoint tendon with dilated superficial ring (n=3), small direct hernial sac (n=1) and lipoma of the spermatic cord (n=1). Surgery consisted of repair of external oblique tear (when present) and prolene darn or lichtenstein mesh repair of the posterior inguinal canal. Twenty-seven patients replied to the questionnaire giving a response rate of 78%; of these, 25 patients (93%: 95% CI 83-100) had returned to normal athletic activities at pre-injury level. There was a marked improvement in level of pain (median pain level=8 pre-operative vs 2 post-operative, p<0.001). Eleven patients (41%) rated the results as excellent, eleven (41%) as good and five (18%) as fair and none worse. Six patients complained of occasional discomfort related to the scar. Three patients complained of recurrence of their symptoms after 4 to 5 months following strenuous exercise. CONCLUSION: Sports hernia presents with a spectrum of surgical findings. Athletes with sports hernia should be considered for routine hernia repair, as the majority of the patients benefit from surgery. It is important to offer a structured rehabilitation programme to maximise the benefits of surgery.

Delayed union stress fractures of the anterior tibia: conservative management.

INTRODUCTION: A conservative method of treating four delayed union stress fractures of the anterior mid-tibia is described, with an illustrative case history. METHODS: Once diagnosed each of the patients was treated in a pneumatic lower leg brace with modified rest. The mean (range) age of the patients was 28 (24-32) years and all were involved in professional or amateur sports. The mean (range) duration of symptoms before diagnosis and definitive treatment of the four fractures was 9 (3-14) months. RESULTS: Use of this technique avoided the need for surgery in this group of patients and allowed return to unrestricted activity an average of 12 months from presentation. CONCLUSION: The treatment is cost effective and avoids the often uncertain results and morbidity associated with surgery for these difficult stress fractures.

Surface effects on ground reaction forces and lower extremity kinematics in running.

INTRODUCTION: Although running surface stiffness has been associated with overuse injuries, all evidence to support this suggestion has been circumstantial. In the present study, the biomechanical response of heel-toe runners to changes in running surface has been investigated. METHODS: Six heel-toe runners performed shod running trials over three surfaces: a conventional asphalt surface, a new rubber-modified asphalt surface, and an acrylic sports surface. The surfaces were categorised according to impact absorbing ability using standard impact test procedures (BS 7044). RESULTS: The rubber-modified asphalt was found to exhibit the greatest amount of mechanical impact absorption, and the conventional asphalt the least. The comparison of peak impact force values across surfaces for the group of subjects demonstrated no significant differences in magnitude of force. However, a significant reduction in loading rate of peak impact force was detected for the rubber-modified surface compared with conventional asphalt (P < 0.1). Although analysis of group data revealed no significant differences in kinematic variables when running on the different surfaces, a varied response to surface manipulation among runners was demonstrated, with marked differences in initial joint angles, peak joint angles, and peak joint angular velocities being observed. DISCUSSION: For some subjects, the maintenance of similar peak impact forces for different running surfaces was explained by observed kinematic adjustments. For example, when running on the surface providing the least impact absorption, an increased initial knee flexion was observed for some subjects, suggesting an increased lower extremity compliance. However, for some subjects, sagittal plane kinematic data were not sufficient for the explanation of peak impact force results. It appears that the mechanism of adaptation varies among runners, highlighting the requirement of individual subject analyses.