Boulton, AJ, RP Betts, CI Franks, et al. :Abnormalities of foot pressure in early diabetic neuropathy. .Diabet Med 4::225. ,1987. .
Pecaroro, RE, GE Reiber, and EM Burgess. :Pathways to diabetic limb amputation: basis for prevention. .Diabetes Care 13::513. ,1990. .
Birke, JA, BD Franks, and JG Foto. :First ray joint limitation, pressure, and ulceration of the first metatarsal head in diabetes mellitus. .Foot Ankle Int 16::277. ,1995. .
Lavery, LA, DG Armstrong, and AJ Boulton. ;Diabetes Research Group :Ankle equinus deformity and its relationship to high plantar pressure in a large population with diabetes mellitus. .JAPMA 92::479. ,2002. .
Quebedeaux, TL, LA Lavery, and DC Lavery. :The development of foot deformity and ulcers after great toe amputation in diabetes. .Diabetes Care 19::165. ,1996. .
Veves, A, HJ Murray, MJ Young, et al. :The risk of foot ulceration in diabetic patients with high foot pressure: a prospective study. .Diabetologia 35::660. ,1992. .
Root, ML, WP Orien, and JH Weed. : “Forces Acting upon the Foot During Locomotion: Abnormal Motion of the Foot. ,” inNormal and Abnormal Function of the Foot, Clinical Biomechanics. , Vol2:, pp165––179. ,295. ,Clinical Biomechanics Corp. ,Los Angeles. ,1977. .
Van Gils, CC and B Roeder. :The effect of ankle equinus upon the diabetic foot. .Clin Podiatr Med Surg 19::391. ,2002. .
Downey, MS . : “Ankle Equinus. ,” inComprehensive Textbook of Foot Surgery. , Vol1:, p715. ,Lippincott Williams & Wilkins. ,Philadelphia. ,2001. .
Oredurf, MS, ES Rohr, BJ Sangeorzan, et al. :An equinus deformity of the ankle accounts for only a small amount of the increased forefoot plantar pressure in patients with diabetes. .J Bone Joint Surg Br 88::65. ,2006. .
Guyton, GP and CL Saltzman. :The diabetic foot: basic mechanisms of disease. .J Bone Joint Surg Am 83::1083. ,2001. .
Boffeli, TJ, JK Bean, and JR Natwick. :Biomechanical abnormalities and ulcers of the great toe in patients with diabetes. .J Foot Ankle Surg 41::359. ,2002. .
Gatt, A and N Chockalingam. :Clinical assessment of ankle joint dorsiflexion: a review of measurement techniques. .JAPMA 101::59. ,2011. .
Caselli, A, H Pham, JM Giurini, et al. :The forefoot-to-rearfoot plantar pressure ratio is increased in severe diabetic neuropathy and can predict foot ulceration. .Diabetes Care 25::1066. ,2002. .
Mueller, MJ, SD Minor, SA Sahrmann, et al. :Differences in the gait characteristics of patients with diabetes and peripheral neuropathy compared with age-matched controls. .Phys Ther 74::299. ,1994. .
Luger, E, M Nissan, A Karpf, et al. :Dynamic pressures on the diabetic foot. .Foot Ankle Int 22::715. ,2001. .
Grant, WP, EJ Foreman, AS Wilson, et al. :Evaluation of Young’s modulus in Achilles tendons with diabetic neuroarthropathy. .JAPMA 95::242. ,2005. .
Lin, SS, TH Lee, and KL Wapner. :Plantar forefoot ulceration with equinus deformity of the ankle in diabetic patients: the effect of tendo-Achilles lengthening and total contact casting. .Orthopedics 19::465. ,1996. .
Hill, RS . :Ankle equinus: prevalence and linkage to common foot pathology. .JAPMA 85::295. ,1995. .
Grant, WP, R Sullivan, DE Sonenshine, et al. :Electron microscopic investigation of the effects of diabetes mellitus on the Achilles tendon. .J Foot Ankle Surg 36::272. ,1997. .
D’Ambrogi, E, L Giurato, MA D’Agostino, et al. :Contribution of plantar fascia to the increased forefoot pressures in diabetic patients. .Diabetes Care 26::1525. ,2003. .
Frykberg, RG, LA Lavery, H Pham, et al. :Role of neuropathy and high foot pressures in diabetic foot ulcerations. .Diabetes Care 21::1714. ,1998. .
Donnery, J and RB Spencer. :The biplane goniometer: a new device for measurement of ankle dorsiflexion. .JAPMA 78::348. ,1988. .
Fernando, DJS, EA Masson, A Veves, et al. :Relationship of limited joint mobility to abnormal foot pressures and diabetic foot ulceration. .Diabetes Care 14::8. ,1991. .
Armstrong, DG, S Stacpoole-Shea, H Nguyen, et al. :Lengthening of the Achilles tendon in diabetic patients who are at high risk for ulceration of the foot. .J Bone Joint Surg Am 81::535. ,1999. .
DiGiovanni, CW, R Kuo, N Tejwani, et al. :Isolated gastrocnemius tightness. .J Bone Joint Surg Am 84::962. ,2002. .
There are no conclusive data to support the contention that diabetic patients have an increased frequency of ankle equinus compared with their nondiabetic counterparts. Additionally, a presumed contributing cause of foot ulceration is ankle joint equinus. Therefore, we sought to determine whether persons with diabetes have a higher prevalence of ankle joint equinus than do nondiabetic persons.
A prospective pilot survey of 102 outpatients (43 diabetic and 59 nondiabetic) was conducted. Demographic and historical data were obtained. Each patient underwent a standard lower-extremity examination, including the use of a biplane goniometer to measure ankle joint range of motion.
Equinus, defined as ankle dorsiflexion measured at 0° or less, was found in 24.5% of the overall population. In the diabetes cohort, 16 of 43 patients (37.2%) were affected compared with 9 of 59 nondiabetic participants (15.3%) (P = .011). There was a threefold risk of equinus in the diabetic population (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.28–8.44; P < .013). The equinus group had a history of ulceration in 52.0% compared with 20.8% of the nonequinus group (P = .003). Equinus, therefore, imparted a fourfold risk of ulceration (OR, 4.13; 95% CI, 1.58–10.77; P < .004). We also found a 2.8 times risk of equinus in patients with peripheral neuropathy (OR, 2.8; 95% CI, 1.11–7.09; P < .029).
Equinus may be more prevalent in diabetic patients than previously reported. Although we cannot prove causality, we found a significant association between equinus and ulceration. (J Am Podiatr Med Assoc 102(2): 84–88, 2012)