Postural control skills, proprioception, and risk of fall in long-term survivor patients treated with knee rotationplasty

Knee A1 rotationplasty is a particular type of limb salvage surgery alternative to hip disarticulation and high transfemoral amputation for skeletally immature children with bone cancers in the distal femur. Notwithstanding optimal functional outcomes, long-term survivor patients often report frequent falls, and a sense of instability during gait, particularly on uneven terrain. This study aimed to assess the postural control, the proprioception, and the risk of fall in these patients, which have not been explored before. Eighteen long-term survivor patients participated in the study. The mean follow-up from surgery was 23 years, mean age 32 years. Patients were assessed using a specific instrumental device (Delos Postural Proprioceptive System) both for the static double-stance and the single-stance test in the open eyes and closed eyes conditions. The double-stance test showed postural instability values within the normal range for healthy individuals, whereas in the single-stance test stability index, when assessed in the average of both lower limbs, values were lower than the literature findings for older individuals. However, when separating the operated from the nonoperated limb performance, standing on the operated limb was very unstable, with a low stability index and a low degree of autonomy, indicating a certain risk of falling, whereas standing on the nonoperated limb had a performance close to normal or even superior. In conclusion, knee rotationplasty patients had very good postural control when standing on both limbs, whereas single stance on the operated limb was compromised, with particular involvement of the proprioceptive component. This may determine a higher risk of falling than their normal-age counterparts and rehabilitation intervention for prevention is indicated.