Background and study introduction

Is there a need for an occupational advice intervention for hip and knee replacement patients?

The impact of hip and knee osteoarthritis on employment

Decreased physical function associated with hip and knee osteoarthritis reduces the likelihood of employment, reduces household income and increases the number of missed workdays for those who are employed.1 The magnitude of the impact varies according to the degree of activity limitation and disease severity.2 A diagnosis of hip or knee osteoarthritis is associated with a reduction in work participation and productivity and an increased risk of work loss.3,4 In a national study of patients in Finland, Kontio et al.5 found that the age-adjusted incidence of disability retirement owing to knee osteoarthritis was 60 and 72 per 100,000 person-years for men and women, respectively. The highest rates of disability retirement in men were found in construction workers, electricians and plumbers, and in women they were found in building caretakers, cleaners, nurses and kitchen workers.5

The cost of work-related musculoskeletal disorders that have an impact on a person’s ability to work is difficult to quantify. Direct (the cost of treatment) and indirect (costs related to the impact of the period of ill health) costs are borne by the individual (impact of ill health on quality of life), employers and society (loss of productivity, need for health care, rehabilitation and compensation).6,7 The Health and Safety Executive calculates the annual cost of workplace injury and ill health on this basis by estimating both the financial cost and the ‘human’ cost.7,8 The Health and Safety Executive estimates that the total annual cost of workplace ill health due to musculoskeletal disorders is £9.7B, equivalent to £18,400 per case.7,8 However, these figures do not take account of non-work-related injuries and ill health and, therefore, are likely to be an underestimate of the total cost. In addition to its financial benefits, working has significant physical, mental and emotional health benefits.9–11 Loss of employment is associated with a reduction in physical function, increased anxiety and depression and increased risk of mortality.12,13 Therefore, earlier return to work (RTW) has potential health benefits as well as socioeconomic benefits.

The role of lower limb joint replacement in patients of working age

Lower limb joint replacements are successful and cost-effective treatments that relieve pain, restore physical function and improve health-related quality of life for patients with hip and knee arthritis.14–17 Currently, > 1 million hip and knee replacements are carried out annually in the USA and > 190,000 are carried out annually in England, Wales and Northern Ireland.18 Projections from 2005 suggest that, by 2030, the number of primary total hip replacements (THRs) and total knee replacements (TKRs) carried out will increase by 174% and 673%, respectively.19

Recent changes to the state pension age, combined with an ageing UK workforce, resulted in a steady increase in the numbers of hip and knee replacements being carried out in patients of working age between 2007 and 2017.18 These changes are also reflected in data from North America, which suggest that over half of all hip or knee replacement procedures will be carried out in patients aged < 65 years by 2030.19 International estimates suggest that between 15% and 45% of patients undergoing either hip or knee replacements are of working age.20,21

According to data published by the National Joint Registry (NJR) for England, Wales and Northern Ireland, 106,334 primary knee replacements22 and 96,717 primary hip replacements23 were carried out in 2017. Of the 91,923 hip replacement patients with available patient data, 18,812 (20.5%) were aged < 60 years (9778 females and 9034 males) and a further 26,295 were aged 60–69 years (28.6%; 15,375 females and 10,920 males). Of the 102,347 knee replacement patients with available patient data, 17,765 (17.4%) were aged < 60 years (10,259 females and 7506 males) and a further 33,523 were aged 60–69 years (32.8%; 18,161 females and 15,362 males).

Occupational advice for patients undergoing hip or knee replacement

There is currently a paucity of information and guidance to support patients returning to work after hip or knee replacement. Over the last 2 years [during the course of the Occupation advice for Patients undergoing Arthroplasty of the Lower limb (OPAL) study], the Royal College of Surgeons of England has produced written information resources to guide recovery including RTW after both hip replacement and knee replacement (example information is available at www.rcseng.ac.uk/patients/recovering-from-surgery/total-hip-replacement/returning-to-work; accessed 16 April 2019). We are not aware of any other currently available occupational advice or information resources specifically tailored to this patient group.

The UK Government currently funds the ‘Fit for Work’ service (in Scotland, the service is called ‘Fit for Work Scotland’).24 This initiative is free for the public to use and is designed to support people in work with health conditions and help with sickness absence. It works alongside existing occupational health services and employer sickness absence policies. Patients can access this service via telephone line support, by visiting the ‘Fit for Work’ websites or by e-mailing the team. However, the patient-facing materials are generic and there is no specific information for hip or knee replacement patients.24

Current evidence relating to return to work after hip or knee replacement

Two systematic reviews examined work status, time to return to work and determinants of RTW in patients undergoing hip or knee replacement.20,21

The most recent and comprehensive review, by Tilbury et al.,20 identified 19 articles:25–43 14 relating to hip replacements, four on knee replacements and one on both. All were cohort studies of either prospective (eight studies) or retrospective (11 studies) design and included the three studies from the earlier Kuijer et al.21 review. Four of the included studies were from the UK.38–41 Among these 19 studies, there was significant variation in the definition of work status both before surgery and after surgery.20 The proportion of patients returning to work ranged from 25% to 95% at between 1 and 12 months after hip replacement and from 71% to 83% at 3–6 months after knee replacement.20 Time to RTW ranged from 1.1 to 10.5 weeks after hip replacement and from 8 to 12 weeks after knee replacement.20 Determinants of a worse ‘work outcome’ after hip replacement included female sex, older age, pain in other joints, failure of the procedure, employment involving physical work, unskilled work and being a farmer.29,32,35 Better work outcomes after hip replacement were associated with younger age, a higher level of education, working within 1 month of surgery, primary osteoarthritis and earlier return of walking ability.29,32,35 Determinants of a faster RTW after knee replacement included female sex, self-employment, better postoperative physical and mental health scores, a higher functional comorbidity index and a disability-accessible workplace.42 Slower RTW after knee replacement was associated with the level of preoperative pain, a physically demanding job and being on workers’ compensation.42

Of the work published in the UK, Mobasheri et al.38 studied 86 hip replacement patients aged < 60 years at a mean of 3 years after surgery, of whom 51 were in work prior to surgery. After surgery, 49 patients (96%) returned to work and an additional 13 gained employment.38 In a similar study, Lyall et al.40 examined 56 knee replacement patients aged < 60 years at a mean of 5 years after surgery. Overall, 40 out of 41 (98%) patients who were employed before their operation returned to their previous work but none of the patients not working prior to surgery found work after their operation. Both studies suggest that high rates of RTW can be achieved in patients at mid-term follow-up (3–5 years). Of the 285 hip replacement patients aged < 65 years studied by Cowie et al.,39 170 (71.1%) were working after their surgery and the mean time to RTW was 13.9 weeks. Of those who returned to work, 132 (78.1%) did so without any workplace restrictions. They also found a negative correlation between time to RTW and increasing age and body mass index (BMI).39 Finally, Foote et al.41 studied 109 patients aged < 60 years at a mean of 3 years post surgery who had previously had a total, unicondylar or patellofemoral knee replacement. The rate of and time to RTW varied by the type of operation, with the TKR (82% had returned to work at a median of 12 weeks) and unicondylar (82% had returned to work at a median of 11 weeks) patients returning significantly sooner than the patellofemoral knee replacement patients (54% had returned to work at a median of 20 weeks).41

A number of additional studies examining RTW after hip or knee replacement have been published since these reviews.

Sankar et al.44 studied RTW in a cohort of Canadian patients and found that the rate of RTW varied according to the joint replaced and the time since surgery. The proportion of patients returning to work was lower for knee replacement than for hip replacement at 1, 3 and 6 months, but by 12 months it was equivalent (1 month: TKR 24%, THR 34%; 3 months: TKR 57%, THR 66%; 6 months: TKR 78%, THR 85%; 12 months: TKR 85%, THR 87%).44 They also reported that the time taken to return to work was improved in males and in patients with a higher level of education and in less physically demanding jobs.44 Dutch researchers have also examined the rate of RTW, duration until RTW and determinants of RTW in patients undergoing total hip or knee replacement.45,46 At 1 year post surgery, 90% of hip and 83% of knee replacement patients had returned to work, but 14% of the hip and 19% of the knee patients had returned to work on reduced hours.45 The mean time to RTW was 12.5 [standard deviation (SD) 7.6] and 12.9 (SD 8.0) weeks for hip and knee replacement patients, respectively.45 Factors associated with a RTW included self-employment and better preoperative activities of daily living subscale scores.46 Preoperative absence from work reduced the chance of returning to work after surgery.46

There have also been three recent publications from the UK.47–49 Scott et al.47 retrospectively reviewed 289 TKR patients aged < 65 years at a mean of 3.4 years after surgery. Overall, 261 patients (90%) were working prior to surgery, of whom 105 (40%) returned to work after surgery, with 89 (34%) returning to the same job at a mean of 13.5 weeks postoperatively. Factors predictive of a successful RTW included younger age and type of work undertaken.47

Malviya et al.48 summarised the qualitative and quantitative literature for RTW after hip or knee replacement. They found that patients have high expectations of the impact of joint replacement surgery on their ability to work and that unrealistic expectations lead to heightened frustration and a slower rate of recovery, preventing them from returning to work. In this setting, supportive care from health-care providers and family support after surgery were helpful in facilitating successful rehabilitation and satisfaction.48 The same research team, Kleim et al.,49 studied 83 patients undergoing hip or knee replacement who were employed prior to surgery. At review, 80 patients had returned to work at median of 12 (range 2–64) weeks. They found that those patients in more manual occupations, those without preoperative sick leave due to their hip or knee arthritis and those with a higher level of qualification returned to employment significantly quicker than the rest of the cohort.49 In addition, hip replacement patients reported a greater improvement than patients after knee replacement did in terms of performance at work (63% vs. 44%) and job prospects (50% vs. 36%).49

Summary of the current literature: key points

Current evidence suggests that:

• A substantial proportion of patients undergoing hip or knee replacement are of working age and the majority are in work at the time of surgery. This number is set to increase in an increasingly aged workforce who will have to work for longer because of changes in the state pension age.
• Lengthy sickness absence can have a negative impact on individual physical and mental health status.
• The cost associated with sickness absence to the patient, employer and the state is significant.
• Occupational advice interventions to support RTW after hip or knee replacement are limited.
• The extent to which RTW is ‘full’ and ‘sustained’ is not known.
• Given the lack of occupational advice interventions and associated resources, there is likely to be significant variation in the advice and information delivered to patients seeking to return to work after hip or knee replacement.
• Return to work is influenced by a range of patient, health process and employment factors.
• The underlying probability of employment varies by age, sex, education level and other factors, meaning that the economic implications of musculoskeletal limitations vary between patients and regions.

The OPAL study

In 2016, the National Institute for Health Research Health Technology Assessment programme commissioned a research call that asked ‘How feasible is a trial to evaluate whether occupational advice, initiated prior to planned surgery for major joint replacement within the lower limb, improves health outcomes in terms of faster recovery to usual activities, including work?’.

The Health Technology Assessment guidance described the need to develop a tailored occupational advice intervention that ensured targeted support and rehabilitation to facilitate RTW as part of this study. This intervention should be proactive and suitable for routine delivery in the NHS alongside the usual-care pathway. There was also a requirement to define the population group, describe usual care and explore important outcomes, such as time to RTW, health-related quality of life, health-care utilisation and proportion of patients requiring workplace occupational health interventions.

Preliminary work undertaken by the OPAL investigators demonstrated a number of evidence gaps related to RTW after major lower limb joint replacement that directed the format and direction of the study. These are described in the following sections.

Population

There is limited evidence about the population of patients undergoing hip or knee replacement who are in work and returning to work after surgery. Further information is required to understand the individualised workplace needs of this group, including an understanding of how job classifications (e.g. manual vs. non-manual), employment status (e.g. employed vs. self-employed), the type of employer (e.g. small and medium-sized enterprises vs. large companies; public- vs. private- or third-sector employer) and how the presence of an occupational health service within the organisational structure influences the potential for early RTW.

The target population for a clinical trial is, therefore, not clearly defined.

Intervention

• Current recommendations guiding RTW are limited and inconsistent. Information is rarely individualised and generic information often fails to provide the patient, employers or health-care teams with the advice required.
• The majority of patients undergoing hip or knee replacement undertake an integrated multidisciplinary team programme of education and rehabilitation spanning the surgical episode. The provision and utility of occupational advice within these ‘usual-care’ pathways is not established and the ability of this service to facilitate RTW has not been explored.
• Studies suggested that the vast majority of ‘fit notes’ are not being used correctly. ‘Fit notes’ offer the patient and employer opportunities for early phased RTW. However, most are advising that patients are ‘not fit’ for work, with few doctors making use of the opportunity to advise on patient function and/or work modifications that might facilitate RTW after surgery.50,51
• There is limited information about the impact of addressing modifiable barriers that prevent RTW or how modifiable psychosocial factors influence RTW behaviours and the specific needs of the patients regarding perioperative care and advice.48,52

There is, therefore, no appropriate occupational advice intervention available that could be used as the intervention in a clinical trial.

Comparison

There is no information about how and when occupational advice is delivered and who is delivering it to hip and knee replacement patients. The rapid and inconsistent adoption of enhanced recovery and early-discharge pathways has led to variations in provision of perioperative care and advice.

‘Standard care’ is therefore not currently defined for use as a study comparator.

Outcome

• There is currently no standardised method of recording RTW. Dichotomous recording of work status (yes/no) is blunt and does not address important aspects of workplace behaviour including absenteeism, presenteeism, return to usual activities and interference with activities. In the UK, > 20% of patients do not return to usual activities and have restrictions in their ability to work after hip replacement.39 Measuring RTW should ideally consider specific elements of the job, the duties and the hours worked.
• Assessment of workplace disability and productivity is poorly reported after hip or knee replacement. Validated tools exist (e.g. the Workplace Activity Limitations Scale and Work Limitations Questionnaire) but little is known about their applicability to the UK workforce and their utility as outcome measures for clinical trials.53

The appropriateness of individual RTW measures for use as primary outcome measures in a clinical trial is currently unclear.

Summary

There is a need for preliminary research to generate relevant evidence and develop an occupational advice intervention to support a future clinical trial. The OPAL study was commissioned to facilitate this.

Objectives

This section is reproduced from Baker et al.54 This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited (see https://creativecommons.org/licenses/by/4.0/). The OPAL study had nine objectives:

1. to evaluate the specific needs of the population of patients who are in work and intend to return to work following hip or knee replacement
2. to establish how individual patients return to work; the role of fit notes, clinical and workplace-based interventions; and how specific job demands influence workplace disability and productivity
3. to establish what evidence is currently available relating to RTW/occupational advice interventions following elective surgical procedures
4. to understand the barriers preventing RTW that need to be addressed by an occupational advice intervention
5. to determine current models of delivering occupational advice, the nature and extent of the advice offered and how tools to facilitate RTW are being currently used
6. to define a suitable measure of RTW through systematic review and evaluation of specific measures of activity, social participation and including specific validated workplace questionnaires
7. to construct a multistakeholder intervention development group to inform the design and establish the necessary components of an evidence-based occupational advice intervention initiated prior to elective lower limb joint replacement
8. to develop and manualise a multidisciplinary occupational advice intervention tailored to the needs of this patient group
9. to test the acceptability, practicality and feasibility and potential cost of delivering the manualised intervention within current care frameworks and as a potential trial intervention.