Contents lists available at ScienceDirect The Foot journal homepage: www.elsevier.com/locate/foot Original Article Pressure distribution under the contralateral limb in Charcot arthropathy with different walking speeds Mohamad Motawea a, ⁎ , Mamdouh El-Nahas b , David G. Armstrong c a Faculty of Medicine, Mansoura University, Egypt b Faculty of Medicine, Port-Said University, Egypt c Southwestern Academic Limb Salvage Alliance (SALSA), Keck School of Medicine of University of Southern California, 1520 San Pablo Street, Suite 4300, Los Angeles, CA, United States ARTICLE INFO Keywords: Contralateral foot Charcot Walking speed Plantar pressure Gait speed ABSTRACT Background: The total contact cast has been recognized as the “gold standard” for treatment of Charcot neuro- osteoarthropathy (CN). However, removable cast walkers (RCWs) became an alternative option especially after resolution of the acute stage. RCWs with an elevated sole construction often induce leg length discrepancy (LLD) that could significantly affects plantar pressure (PP) distribution in diabetic patients with neuropathy. Aim: To study the additional effect of walking speed on PP abnormalities induced by LLD. Method: The study included 16 patients with diabetes (59 ± 8.8 years; 8 men and 8 women), with unilateral CN offloaded by RCW. In-shoe PP distribution was measured using F-scan (Tekscan Inc.), whilst patients walked at their normal speed (53 ± 4 steps/min), versus short slow steps (24 ± 3/min) under the two walking conditions: (1) neglected LLD, and (2) corrected LLD. Results: The greatest reduction in PP was seen during reduction of walking speed, with corrected LLD, followed by corrected LLD with normal walking speed, followed by neglected LLD with slowing of walking speed. The highest PP was found when the patient remain on their normal walking speed and LLD was neglected. Conclusion: The contralateral foot of CN offloaded with RCW, is subjected to high pressure loads beneath the hallux, 1st, 2nd, 3rd, and 5th metatarsal heads. As such, care should be taken not only to avoid minor LLD, but to also advise the patient to practice short slow steps while walking, so that pressure overload on contralateral limb and its possible contribution to the development of bilateral Charcot, could be minimized. 1. Introduction Pressure overload is likely to be one of the precipitating factors that can lead to Charcot joints. That is why offloading remains the mainstays of therapy, and is the most important management in the acute stages [1]. Armstrong and Lavery found that the peak plantar pressures were significantly higher in the patients who had acute neuro-osteoarthro- pathy (CN), and those who had neuropathic ulceration compared to those who had neuropathy without ulceration [2]. The total contact cast has been recognized as the “gold standard” for treatment of Charcot neuro-osteoarthropathy (CN) [3–6]. However, removable cast walkers (RCWs) were found to be the most effective of the removable devices [7], they became an alternative option especially after resolution of the acute stage [8–10]. Armstrong et al. showed that bilateral Charcot is estimated to be approximately 9% [11]. Another study reported that approximately 8 out of 140 patients with unilateral CN (5.7%), who were offloaded with RCWs, developed CN in the con- tralateral foot within one year post follow up period [12]. RCWs with an elevated sole construction often induce leg length discrepancy (LLD). Nahas et al. [13] reported that minor LLD could significantly affects plantar pressure distribution in diabetic patients with neuropathy. The short leg of patients with neuropathic diabetic foot, was subjected to higher pressure load beneath the total foot, mid- foot and 2nd, 3rd, 4th and 5th metatarsal heads; inevitably exposing the shorter foot to risk. Therefore, care should be taken to avoid minor LLD induced by offloading devices [13]. White et al. [14] and O’Toole et al. [15], also found that the shorter limb sustained higher loading patterns. The walking speed can also affect the pressure applied to the feet [16,17]. Segal et al. [18] and Warren et al. [19], found that walking speed is positively associated with peak plantar pressure in people with diabetes. The peak plantar pressures are considerably reduced during a shuffling gait with short steps [16,17] Brand attributed that to the https://doi.org/10.1016/j.foot.2019.01.008 Received 18 June 2018; Received in revised form 14 January 2019; Accepted 16 January 2019 Abbreviations: CN, Charcot neuro-osteoarthropathy; LLD, leg length discrepancy; NLLD, nullified leg length discrepancy; RCWs, removable cast walkers ⁎ Corresponding author at: Faculty of Medicine, Mansoura University, University District Building No. 46, Mansoura, 35516, Egypt. E-mail addresses: drmotawe3@mans.edu.eg (M. Motawea), drmamdouh@hotmail.com (M. El-Nahas), armstrong@usa.net (D.G. Armstrong). The Foot 39 (2019) 15–21 0958-2592/ © 2019 Published by Elsevier Ltd. T