Efficacy and Acceptability of Mobilisation and Stretches of the Foot and Ankle in People with Diabetic Peripheral Neuropathy

Abstract

People with diabetic peripheral neuropathy and limited joint mobility syndrome (LJMS) can experience increased forefoot peak plantar pressures (PPPs). Elevated PPPs are a risk factor for diabetic neuropathic foot ulceration. Diabetic peripheral neuropathy can also affect balance and increase the risk of falling. This thesis investigated the efficacy and acceptability of foot and ankle mobilisations combined with home stretches in people living at risk of neuropathic diabetic foot ulceration and falling. A systematic review and meta-analysis examined the effects of foot and ankle physical therapy modalities for the management of foot and ankle joint mobility, PPPs, and balance. The review highlighted that combined exercise intervention programmes integrating stretches increased total ankle ROM by 1.76 degrees (95% CI 0.78-2.7) and reduced PPPs by 32kPa (95%CI -42.42 - -19.21). The review highlighted that no studies to date have looked at combined foot and ankle mobilisations and stretches on foot and ankle mobility, PPPs, and balance. This informed a proof-of-concept randomised controlled trial (RCT). In my proof-of-concept RCT, people with diabetic peripheral neuropathy (n=61) were randomly assigned to an intervention (n=31) or control group (n=30). The intervention consisted of a 6-week programme of ankle and 1st metatarsophalangeal (MTP) joint mobilisations and home stretches. The control group received usual podiatry care. Outcome measures were taken at baseline (T0); 6-weeks post intervention (T1) and at 18-weeks follow up (T2) by a blinded assessor. The primary outcome was dynamic ankle dorsiflexion range of motion (ROM) at T1 using three-dimensional (3D) motion analysis. Secondary outcomes included static 1st MTP and ankle joint ROM, stride length, dynamic peak plantar pressure, forefoot-to-rearfoot pressure ratio, perceived walking ability and balance with measures of postural sway and functional reach. Results were reported according to CONSORT guidance. At T2 there was no difference between both groups in ankle dorsiflexion in stance phase (primary outcome measure) or any other dynamic measurements including plantar pressure and balance. Compared to the control group, the intervention group showed differences in static ankle dorsiflexion range (left 1.52cm and 2.9cms, right 1.62cm and 2.7cm) at 6 (T1) and 18 weeks (T2) respectively p<0.01). Between group differences were also seen in left hallux dorsiflexion (2.75°, p<0.05) at T1 and in right hallux dorsiflexion ROM (4.9°, p<0.01) at T2 follow up. Further, functional reach showed a difference in the intervention group (T1=3.13cm p<0.05 and T2=3.9cm p<0.01). A qualitative study was embedded in the RCT using semi-structured interviews with thematic analysis to explore the experiences of participants (n=16) in receiving foot and ankle mobilisations with home stretches to gain an insight into barriers and facilitators influencing adherence to treatment. Perceived improvement in foot and ankle function and building good rapport with the physiotherapist were factors that positively influenced participant exercise adherence and overall acceptability to the intervention. A focus group with the treating therapists (n=3) revealed concerns about the intervention because the study used a higher dosage of mobilisations than that usually seen in clinical practice. It also underlined whether it is appropriate to use outcomes that capture biomechanical data instead of functional outcome measures that are meaningful to patients. In conclusion, this is the first study to investigate whether mobilisations combined with stretches can reverse the effects of diabetic glycosylation on foot and ankle mobility. The findings from the RCT found no changes in the primary outcome. However, differences between groups in static ankle and hallux ROM, and functional reach test could be associated with some participants reporting functional improvement in their foot and ankle. Future work should focus on assessing the effects of mobilisation in a group with LJMS that affects ankle range while walking. Further, implementation issues such as who might be best suited to deliver the intervention within a healthcare setting needs to be considered prior to undertaking a multi-centre RCT.