after approval by the institutional review board of the federal university of so paulo , brazil , 500 patients with dm from the diabetic foot outpatient clinic of orthopaedic department of the federal university of so paulo were enrolled in a prospective study to evaluate the results of minimally invasive surgery to treat forefoot ulcerations . patients were included for surgery in the study if they had a history of dm type 2 for at least 5 years duration , decreased plantar sensation ( detected with 10 g semmes  weinstein monofilament ) , dorsiflexion range of motion of the ankle equal to or less than 10 measured via goniometer ( fig . 1 ) , palpable distal pulse , and history of forefoot ulceration healed with proper treatment ( 10 , 11 ) . patients were excluded from surgery if they had an infected ulceration , dorsiflexion of the ankle greater than 10 , and absent distal pulse on clinical examination . fifty - two patients met the study criteria and the average age was 66.4 years . a modification of white 's surgical technique was performed to address the equinus contracture with three hemisections of the achilles tendon , with specific configuration according to the clinical presentation of the hindfoot and ankle ( 10 ) . the proximal and distal hemisections were made at the same side of the achilles tendon , and the intermediate cut was performed at the opposite side . a valgus hindfoot received proximal and distal hemisections at the lateral side of the tendon , whereas a varus hindfoot was addressed with medial side hemisections ( fig . 2 ) . the postoperative care included plaster short - leg cast immobilization to maintain maximal dorsiflexion . after 1 week , a total contact cast with full weight bearing as tolerated was applied for 6 weeks . physical therapy was then initiated to maintain ankle position , calf strengthening , proprioceptive improvement , and gait training in an accommodative walking boot for an additional 6 weeks ( 8 , 12 ) . 
 fig , 2 . a modification of white 's surgical technique was performed to address the equinus contracture with three hemisections of the achilles tendon , with specific configuration according to the clinical presentation of the hindfoot and ankle ( 10 ) . the proximal and distal hemisections were made at the same side of the achilles tendon , and the intermediate cut was performed at the opposite side . a valgus hindfoot received proximal and distal hemisections at the lateral side of the tendon , whereas a varus hindfoot was addressed with medial side hemisections ( fig . 2 ) . the postoperative care included plaster short - leg cast immobilization to maintain maximal dorsiflexion . after 1 week , a total contact cast with full weight bearing as tolerated was applied for 6 weeks . physical therapy was then initiated to maintain ankle position , calf strengthening , proprioceptive improvement , and gait training in an accommodative walking boot for an additional 6 weeks ( 8 , 12 ) . fifty - two patients in the study underwent surgical treatment consisting of percutaneous achilles tendon lengthening through a modified white 's technique to treat forefoot ulcerations . forty - eight patients ( 92% ) had no recurrence of ulcerations during the follow - up and demonstrated improved foot function . follow - up was performed through a multidisciplinary team to maintain metabolic and glycemic control , provide education strategies to prevent recurrence of lesions , and also physical therapy for adequate function and protection . patients with recurrent forefoot ulcerations ( n=4 feet ) , which occurred in the same location as the original ulcer , also underwent a percutaneous distal metatarsal osteotomy ( fig . 3 ) of the associated metatarsal and were permitted full weight bearing in a total contact cast for 4 weeks . thereafter , walking boots and custom shoes were prescribed . during the study , none of the patients presented with infection , pain , or necrosis . diabetes mellitus is a chronic disease with potential complications that are responsible for high rates of morbidity and mortality . the presence of plantar foot ulcerations in these patients increases the risk of infection , sepsis , and amputation . early detection , multidisciplinary treatment , and education are critical for preventing any related lower extremity amputations . our study demonstrated success in 92% of patients for prevention of recurrent forefoot ulceration in patients with ankle equinus , suggesting the usefulness of a minimally invasive approach for percutaneous lengthening of the achilles tendon in these patients . dm can affect all components of the nervous system , including light touch sensation , motor control , pain recognition , proprioception , and autonomic function . absence of protective sensation and the presence of foot deformities are the clinical factors with the highest correlation for the development of foot ulcerations and eventual lower extremity amputation ( 8 , 1315 ) . in fact , 85% of lower limb amputations are preceded by plantar ulcerations ( 16 ) . prevention and early treatment of these lesions can maintain satisfactory biomechanical and functional longevity of the lower extremity . longer duration of dm is associated with the development of calf shortening due to structural changes , glycated collagen of tendon fibers , and the presence of peripheral sensory neuropathy , contributing strong risk factors for forefoot ulceration . clinical and imaging assays demonstrate that these patients often present with heterogeneous patterns of tendon fibers and sometimes contain internal calcifications . anatomic physiologic patterns show significant modification within the calcaneal tendon that becomes a solid tendon ( 12 , 1719 ) . as a consequence , patients present with limited range of motion of the ankle , physiologic loss of collagen elasticity , gait alterations , and inability of the foot to act as an energy absorber leading to elevated forefoot pressures ( 9 , 18 , 19 ) . diabetic prophylactic foot surgery plays an important role in establishing optimal biomechanical function as well as preventing and treating foot ulcerations ( 8 , 11 , 12 , 17 ) . our study illustrates that percutaneous achilles tendon lengthening with a modification of white 's original technique constitutes an important mechanism to restore appropriate range of motion to the ankle , improving gait quality , and preventing recurrent forefoot ulcerations . when necessary in cases of ulcer recurrence after achilles tendon lengthening , the percutaneous distal metatarsal osteotomy has been recommended ( 9 ) . we believed that the ulcer recurrences were associated with anatomic disturbance of the involved metatarsal such as elongation and plantar flexion ( 9 ) . this study also highlights successful treatment of forefoot ulcerations and prevention of recurrence during a follow - up period in a large cohort of subjects via a multidisciplinary team approach . prophylactic surgery of the diabetic foot is a viable option in advanced treatment clinics to avoid foot complications and treat forefoot ulceration in diabetic patients . in an effort to reduce forefoot pressures and subsequently prevent ulcer recurrence , our study demonstrates an effective , reproducible surgical technique for percutaneous achilles tendon lengthening with good tolerance by patients , and minimal complications . the authors have not received any funding or benefits from industry to conduct this study .
complications of diabetes mellitus constitute the most common indications for hospitalization and non - traumatic amputations in the usa . the most important risk factors for the development of diabetic foot ulcerations include the presence of peripheral neuropathy , vasculopathy , limited joint mobility , and pre - existing foot deformities . in our study , 500 diabetic patients treated for plantar forefoot ulcerations were enrolled in a prospective study from 2000 to 2008 at the federal university of so paulo , brazil . 
 fifty - two patients in the study met the criteria and underwent surgical treatment consisting of percutaneous achilles tendon lengthening to treat plantar forefoot ulcerations . 
 the postoperative follow - up demonstrated prevention of recurrent foot ulcerations in 92% of these diabetic patients that maintained an improved foot function . in conclusion , 
 our study supports that identification and treatment of ankle equinus in the diabetic population may potentially lead to decreased patient morbidity , including reduced risk for both reulceration , and potential lower extremity amputation .