(P 492) BALANCE AND GAIT OUTCOMES AFTER 1-YEAR POST-OPERATIVE HEMIPELVECTOMY SURGERY

Objective: Currently, the focus when considering post-operative functional assessment in sarcoma patients is to measure their disability, while balance (postural stability( issues and their investigation is lacking in most sarcoma research. Static balance (during standing) has been investigated in two pilot studies (De Visser 2001, Furtado et al 2020) respectively, but there are no studies that look at dynamic balance (during walking) even though people with musculoskeletal cancers present with significant balance problems and falls in the long-term. This study aimed to investigate the feasibility of assessing dynamic balance after hemipelvectomy surgery for a sarcoma.

Methods: This is a retrospective cross-sectional pilot and feasibility study (Ethics approval: 21/WA/0027) analysing existing datasets from the Gait Real-time Analysis Interactive Laboratory (GRAIL) database at RNOH for 10 sarcoma patients who underwent hemipelvectomy one year ago and 10 healthy participants (controls) . The margin of stability (MOS) was used to quantify dynamic balance ability in all participants during treadmill walking. MOS in the anterior, posterior, lateral and medial direction, stride length and stride width of the patients and controls at heel contact or during the swing phase were compared using the Mann-Whitney U-test.

Results: 10 patients (nine males and 1 female) with pelvic sarcomas of mean age, weight and height of 41(±13) years, 78.4(±16.9)kg, 1.77(±0.10)m were enrolled into this study. No statistically significant differences were seen in patient MOS between the operated and non-operated side during the swing phase (p>0.05), but it was found that the patient's stride length was usually longer on the operated side than on the non-operated side (p < 0.05*). Furthermore, it found that patients had significantly smaller values of posterior MOS during the swing phase (p < 0.05*) and smaller values of medial MOS during heel touch compared to controls (p < 0.05*) (Fig. 1).

Conclusion: This is the first study demonstrating that it is feasible to quantify dynamic balance in the sarcoma population. It is pertinent to note that, MOS identified struggling the patients with balance issues during walking. However, no differences were found between the balance of the operated and non-operated side of the leg during the swing phase and the stride length of the operated leg was longer than the non-operated leg in patients after hemipelvectomy. Encouraging balance training using physiotherapy and rehabilitation strategies when walking in the posterior and medial directions, may help to improve overall body balance.