Tendon Lengthening: Is It A Viable Option For Forefoot Ulcers?
The reported recurrence rate of foot ulcers in patients with diabetes treated without TL after three years was 61 percent (280 of 458).23 After performing TAL, Yosipovitch and Sheskin had three ulcer recurrences in eight patients (38 percent) in a four- to five-year follow-up, and Mueller, et. al., saw recurrence in 38 percent (10 of 26) at a two-year follow-up.11,16 The low rate of ulcer recurrence, 12 percent (four of 33), in our series compares favorably to previous studies, in which patients underwent treatment without TL, with TL and in the aforementioned TCC studies, which revealed a 20 percent (20 of 102) and 81 percent (21 of 26) recurrence at a two-year average follow-up.11,15,16,23 Lin, et. al., saw no recurrences but had shorter follow-up (17 months vs. 36 months) and treated fewer ulcers (15).18
The controlled, randomized study of Mueller, et. al., showed a high rate of ulcer healing: 89 percent (29 of 33) with TCC and 100 percent (30 of 30) when they combined TCC with TAL.16
Their results are similar to our study in which 97 percent (33 of 34) healed with TL alone. This study indicates that TCC is not necessary for forefoot ulcer healing. Mueller, et. al., reported a 38 percent ulcer recurrence rate with TL (10 of 26) while our ulcer recurrence rates were 12 percent (4 of 33) in healed ulcers or 10 percent (1 of 10) of healed metatarsal head ulcers in patients with diabetes. Both of these results are much less than the reported ulcer recurrence rate – 81 percent (21 of 26) – with TCC alone.16,23
Dorsiflexion metatarsal osteotomy also had a high rate of successful healing of neuropathic forefoot ulcers of 95 percent (21 of 22).17 However, there was a 68 percent complication rate with seven patients developing acute Charcot disease, three developing midfoot ulcers, three deep wound infections, two transfer ulcers under adjacent metatarsal heads and one below-knee amputation. Our study revealed no new or worsening Charcot disease, new midfoot ulcers, transfer metatarsal ulcers or wound infections. As I noted previously, there were three transfer lesions, all of which eventually healed.
In this study, researchers considered gangrene to be a contraindication to TL. However, they considered patients without pulses potentially salvageable. There were no incision problems and ulcers healed in all but one of these patients.
In a study of diabetic amputations, 84 percent (67 of 80) were attributed to ulcers.23 Two of the 24 patients (8 percent) in our study required amputation of the leg for gangrene but none required amputation for progressive infection from an ulcer at average follow-up of 36 months. This is less than the reported total amputation rate of 22 percent (101 of 458) at three years of observation of patients with diabetes with prior foot ulcers.23 Their rate of amputation for complications of recurrent ulcers – 21 percent (98 of 458) – was much higher than our study, in which there were no amputations caused by recurrent ulcer complications. Granted, the number of patients in our study is small by comparison so another study of more patients is necessary to confirm the decrease in amputation rate when clinicians employ TL procedures.
A Closer Look At The Vulpius Technique
Lin, et. al., and Mueller, et. al., lengthened the Achilles tendon by Hoke’s method of hemisection at three levels of the tendon.16,17,24 Yosipovitch and Sheskin used the subcutaneous tenotomy method of Strohmeyer.24,25 Nishimoto, et. al., preferred gastrocnemius recession for diabetic forefoot ulceration because of the lower risk of over-lengthening, calcaneal gait and plantar heel ulceration with a 16 percent recurrence rate.26
I chose the Vulpius technique because of prior favorable experience using this technique in children with cerebral palsy. This technique allows immediate full weightbearing in a cast with less over-correction and incision problems.20 Takahashi and Shrestha successfully used the Vulpius procedure to correct equinus deformity of the ankle in 230 adults after cerebrovascular accident.27 The average age was 68 and 98 patients had diabetes. They had no wound or tendon problems and allowed standing in a brace (ankle foot orthosis) the next day.