The complex healing process of venous leg ulcers (VLUs) is widely documented in the literature (Dealey, 2008; Domingues et al, 2018; Baranoski and Ayello, 2020). Research into this issue has informed best practice statements (Elstone et al, 2021; Hopkins et al, 2022). Unfortunately, the complexity of wound healing continues to challenge primary health professionals and is an increasing financial burden across healthcare services (Guest et al, 2017).
Compression therapy is well established within best practice statements for VLU management and remains an essential ‘gold standard’ treatment to improve venous leg insufficiency (O'Meara, 2009; Elstone et al, 2021; Hopkins et al, 2022). In addition to this, an increase in mobility that incorporates ankle motion and contractability of the calf muscle pump is known to be an important adjunct to reduce venous hypertension, assist venous return, and improve lower leg functionality (Williams et al, 2014; Domingues et al, 2018). This positive relationship has attracted considerable attention in the past decade, in both scholarly and popular literature, particularly in the benefit of a prescribed exercise intervention (PEI) on the healing rate of VLUs (Simka, 2007; O'Brien et al, 2012; Qiu et al, 2022). As such, current best practice statements for VLU management have recommended exercises to increase lower leg mobility (Scottish Intercollegiate Guidelines Network and Quality Improvement Scotland, 2010; Hopkins et al, 2022). Unfortunately, a lack of empirical studies exploring the effect of a PEI on VLU healing rates has contributed to a lack of standardisation between recommendations, making application to nursing practice fallible and open to subjectivity (Simka, 2007; Qiu, et al, 2022).
Aim
This literature review explored the use of a PEI as an adjunct to improve VLU healing in housebound patients using compression therapy. The aim was to determine if an unsupervised PEI is beneficial to VLU healing alongside compression therapy.
Definitions
For the purpose of this review, a house-based PEI is one that can be performed in the patient's home and does not require the patient to leave their home to complete. A housebound patient is defined as someone who is unable to leave their home environment due to physical and/or psychological illness.
Method
A search of the following databases was conducted: the Cumulative Index of Nursing and Allied Health Literature (CINAHL), Google Scholar, and Medline. Search criteria included studies published between 2009 and 2023, using the search terms venous leg ulcer; exercise; compression; house-based and housebound. Performance bias was unable to be assessed because it is not feasible to blind people from exercise interventions (Qiu et al, 2022).
Results
Five randomised controlled trials (RCTs) were identified between 2009 and 2021 in the following inclusion criteria: in English, published between 2009 and 2023, randomised controlled trial, VLU healing as an outcome, unsupervised exercise intervention that engages the calf muscle pump as an adjunct to compression therapy, and house-based.
Two open-label RCTs by O'Brien et al (2013) and Jull et al (2009) were identified with participant sizes of n=11 and n=40, respectively. Jull et al (2009) investigated the effect of a PEI where the participants performed standing heel raises against a wall. No significant difference (P=0.08) in ulcer area was noted after 12 weeks. The second study by O'Brien et al (2013) was delivered through a community nursing service and researched the effect of a PEI starting with seated heel raises (both legs), progressing to standing heel raises (both legs) and then to standing one-legged heel raises. The participants in the control group received no additional form of exercise instruction and were instructed not to alter their normal activity habits (O'Brien, 2013). No significant difference (P=0.34) was observed in the reduction in ulcer area after 12 weeks. A significant difference was reported in the calf muscle pump function (P<0.05) in the PEI group. A 77% reduction in ulcer area was noted in the PEI group and 45% in the control group.
A four-arm single-blinded RCT by Mutlak et al (2018) included 80 participants split between four groups – a control group, a compression-only group, a PEI group, and a PEI with compression group. The PEI consisted of 10 dorsiflexions every hour the participants were awake. The PEI group (P=0.001) and the PEI group with compression (P<0.001) showed a significant reduction in ulcer area after 12 weeks, with the PEI with compression group showing the largest reduction.
A single-blinded RCT by Domingues et al (2018) explored the effect of a repetitive ankle/foot motion exercise, performed three to four times a day. A significant reduction in VLU area was observed at 30 days (P=0.0197), 60 days (P=0.0472) and 90 days (P=0.0116). A digital method of measuring VLU area was used. The study's participant size reduced from 102 (control group=53; PEI group=49) to 71 (control group=36; PEI group=35) owing to a high number of drop-outs after allocation. No adverse effects were reported by the participants.
A feasibility single-blinded RCT by Jonker et al (2020) with 32 participants, explored the use of a seated plantar resistance exercise using a pedal machine to promote VLU healing. The results showed no significant difference in VLU area (P=0.73), with a small participant size (n=32). This was the only study to report P values at week 0 (P=1.0) and week 6 (P=0.79) in addition to week 12 (P=0.73).
Variations in the methods used by the five studies to measure VLU area were identified. These were a manual ruler-based method (Mutlak et al, 2018), an acetate-tracing method and a manual ruler-based method (Jonker et al. 2020), and a digital method (Jull et al, 2009; O'Brien et al, 2013; Domingues et al, 2018).
All five studies adopted varying methods to promote and monitor PEI adherence. All PEI groups received initial face-to-face instruction on performing the exercises. The location of this was either house-based (O'Brien et al, 2013) or the exact location was unclear (Jull et al, 2009; O'Brien et al, 2013; Mutlak et al, 2018; Jonker et al, 2020). Additional methods to promote adherence included a leaflet (Mutlak et al, 2018), regular phone call follow-ups (Domingues et al, 2018; Mutlak et al, 2018), an option for bi-weekly text messages (Jonker et al, 2020), in-person meetings every 4 weeks (Domingues et al, 2018), weekly visits to outpatient clinics and/or telephone calls (O'Brien et al, 2013) and self-reporting diaries (Jull et al, 2009; O'Brien et al, 2013; Mutlak et al, 2018; Jonker et al, 2020). Jonker et al (2020) had a low uptake (13%) of optional text messages. O'Brien et al (2013), Jull et al (2009) and Mutlak et al (2018) reported problems with PEI adherence and participants completing a self-reported diary.
Discussion
Three of the studies examined showed no statistically significant reduction in ulcer area (Jull et al, 2009; O'Brien et al, 2013; Jonker et al, 2020). The two early studies by O'Brien et al (2013) and Jull et al (2009) had notable methodological weaknesses, the primary being the high risk of detection bias. Jull et al (2009) reported a relatively small participant number (n=40) and self-reported adherence to the PEI. This high chance of detection bias was highlighted in systematic reviews by Smith et al (2018) and Jull et al (2018) and a scoping review by Qiu et al (2022) who all placed less value on the study for these reasons. Despite O'Brien et al (2013) reporting no statistically significant results, the findings could suggest a clinical significance due to a reduction of 77% in ulcer area in the PEI group and 45% in the control group. The exceptionally low participant size (n=11) was likely the causal factor and also prevented generalisability to the wider population. The study did report a significant improvement in calf muscle pump function (P=<0.05) in the PEI group; however, the study was further limited in that adherence was monitored by a self-reporting diary with inconsistent completion between groups. Despite these limitations, the studies set out some basic groundwork for future research.
Although Jonker et al (2020) presented no statistically significant reduction in ulcer area, there was a decreasing trend in the P value for the PEI group over the 12 weeks, which could imply an improvement in VLU healing trajectory. The primary limitation of the study was the small participant size, which contributed to a non-significant reduction in VLU area. Additionally, on allocation, the PEI group exhibited more VLU chronicity than the control group, and as chronicity is well-known to delay healing (Gethin et al, 2020); this reduces the validity of the results.
Two promising studies by Mutlak et al (2018) and Domingues et al (2018) presented statistically significant reductions in VLU area. Results by Mutlak et al (2018) included a compression-only group that showed no measurable difference in ulcer area. It could be suggested that compression and exercise complement each other, in that the positive effect of exercise on lower leg circulation enhances lower leg function and enables compression therapy to work more effectively. Domingues et al (2018) commented that compression alone may require a longer time to have a positive effect on ulcer healing. A Cochrane review by Shi et al (2021) assessed the effect of compression therapy versus no compression for treating VLUs and found that people treated with compression bandages are likely to experience full ulcer healing within 12 months and more quickly than people without compression. This reinforces that a longer time is required for compression alone to induce a positive effect on VLU healing. Overall, these findings suggest a positive link between a PEI with compression and VLU healing; however, possible sources of bias exist. An unclear risk of allocation concealment bias is present as the allocation was not sequentially numbered. Additionally, a low risk of detection bias in terms of blinding exists. A systematic review by Jull et al (2018) substantiated this finding. Detection bias further devalues the Mutlak et al (2018) study as the method used to measure ulcer area was a ruler-based technique, increasing the risk of assessor error. Mutlak et al (2018) argued that the ruler-based technique was reliable based on evidence from a study by Brown (2003) that reported concerns over the use of digital methods being high cost, impractical, and time-consuming. A later study by Bilgin and Günes (2013) compared three wound measurement techniques for measuring pressure ulcer size and shape. They concluded that the ruler-based technique was reliable for measuring small circular shapes but tended to lead to overestimation of larger and/or irregularly shaped wounds. Therefore, digital or acetate tracing methods were recommended and are generally accepted within this field of research, to reduce detection bias.
Despite early studies by O'Brien et al (2013) and Jull et al (2009) using a digital method to measure VLU area, this does little to improve study validity and only further highlights the negative impact of their methodological weaknesses. Jonker et al (2020) measured ulcer areas using both an acetate-tracing method and a ruler-based method. Unfortunately, data for wound area using the acetate method was not completed for three participants in the PEI group and four in the control group, creating a high risk of attrition bias, further devaluing the study.
Domingues et al (2018) used a digital method to measure VLU area and presented a well-designed study achieving a statistically significant reduction in VLU area. Domingues et al (2018) acknowledged some study limitations, such as the small participant size and self-reported adherence. The small participant size was caused by a high number of drop-outs after allocation; however, no adverse effects were reported, and despite the high drop-out rate, the participant size is one of the highest compared to the other studies.
The methods used to promote adherence varied between studies. Indeed, adherence to a PEI and diary completion could be a challenge for housebound patients for varying reasons such as home environment, perceived ability, childhood experiences of exercise, forgetfulness, or mental ability (Schutzer and Graves, 2004). Lifestyle habits and perceived barriers to physical activity are often ingrained. Jonker et al (2020) stated that obtaining data from a community setting was more challenging than in a clinic or GP setting. Domingues et al (2018) achieved a significant improvement in wound healing yet was the only study not to include a self-reporting diary. Therefore, it could be suggested that there is no benefit to using a self-reporting diary to aid adherence, because there is no guarantee that the entries are a true reflection of activity, and may only cause patients feelings of pressure to complete their diaries, particularly in elderly and housebound patients.
Mutlak et al (2018) noted that, although satisfactory unsupervised adherence was achieved, a vast effort from the health professionals was required during scheduled contact time to maintain participant enthusiasm, and therefore recommended supervised PEIs. Two RCTs by Kelechi et al (2020) and Klonizakis et al (2018) assessed the use of a supervised PEI for patients with VLUs. Although they had low participant sizes of n=17 and n=39, respectively, Kelechi et al (2020) achieved 100% adherence with 100% of the participants with one-to-one telecoaching and Klonizakis et al (2018) achieved 100% adherence with 72% of participants in a clinic-led PEI. Another RCT by Szewczyk et al (2010) with 32 participants showed a significant improvement (P<0.05) in ankle-joint mobility in a supervised versus unsupervised group. A scoping review by Qiu et al (2022) corroborated this, stating that the studies with supervised PEIs achieved better adherence and clinical outcomes. Alternatively, a systematic review by Jull et al (2018) recommended that a scalable approach could be used where health professionals monitor and encourage patient development during scheduled visits, enabling adjustments to activity levels dependent on personal ability.
Schutzer and Graves' (2004) study explored barriers and motivations to exercise in older adults, where the clinician/patient relationship was shown to be advantageous in promoting adherence to exercise, particularly in elderly people, due to frequent contact and respectful attitudes.
Unfortunately, as community nursing services do not generally facilitate patient visits for exercise interventions, full nurse supervision is not an option, although encouraging adherence and reinforcement could be incorporated into scheduled, face-to-face patient visits. In addition, opportunities exist for a degree of supervision to be provided by family or carers during everyday contact.
Conclusion
Despite the limited evidence in terms of small sample size and varying degrees of bias, some statistically and clinically significant results in wound healing outcomes were achieved. Taken together, these findings suggest that, for suitable housebound VLU patients, a benefit to wound healing could be achieved from a PEI, as an adjunct to compression. Recent systematic reviews have reached a similar conclusion (Smith et al, 2018; Jull et al, 2018; Qiu et al, 2022). The lack of standardisation between types of PEI prevents the recommendation of a specific exercise, only that the exercise should engage the calf muscle pump. It is unlikely that a recommendation of a PEI would disadvantage housebound patients, given the known advantages of physical activity and the negative effect of extended inactivity on lower leg function (Bowden-Davies et al, 2019). However, individual ability must be considered, because housebound patients will likely have reduced levels of mobility, restricting the type and amount of physical activity they are capable of doing. Undoubtedly, a PEI should be included in the community nursing holistic model of care for VLU management.
Further research
Although the evidence base on this subject is growing, a lack of quality research exists. Future studies with larger sample sizes and longer durations, focusing on housebound patients and the benefit of carer support, are required.
Recommendation
A recommendation can be made to implement, encourage, and monitor a PEI, such as dorsiflexion, ankle/foot rotation, or sitting/standing heel raises, for VLU patients, wearing compression therapy. This would be individualised to the patient and include an initial discussion explaining the benefit of the PEI, to determine the patient's physical ability and achieve concordance with the PEI type, frequency, and duration. With patient consent, family or carers could be included in the process to provide encouragement and reinforcement. Inclusion in scheduled visits would allow community nurses to provide patient and family reassurance, check understanding, and promote adherence.
As a result of this review care plan revision is currently ongoing in the author's local district nursing service to include implementation, encouragement and monitoring of a PEI for VLU patients, wearing compression therapy.
KEY POINTS
- Venous leg ulcers (VLUs) are a growing challenge for community health professionals
- Healthcare services are experiencing an increasing financial burden due to VLUs
- Prescribed lower leg exercises for housebound patients could improve lower leg function and VLU healing outcomes, as an adjunct to compression therapy
- Community nurses could incorporate a prescribed lower leg exercise into VLU care planning to improve VLU healing outcomes
CPD reflective questions
- Think about the research findings discussed in this article and how they could be used to improve your practice
- Have you considered using prescribed lower leg exercises in your venous leg ulcer patients? Is this something you could investigate?
- Consider how using this and other research on prescribed lower leg exercises could improve patient care in your area of practice