SLR - November 2022 - Shawn Kashef, DPM
Title:Concomitant Achilles Tendon Lengthening with Transmetatarsal Amputation for the Prevention of Late Forefoot Ulceration
Reference
Bullock MJ, Gill CM, Thomas R, Blebea J. Concomitant Achilles Tendon Lengthening with Transmetatarsal Amputation for the Prevention of Late Forefoot Ulceration. J Bone Joint Surg Am. 2022 Oct 5;104(19):1722-1729. doi: 10.2106/JBJS.21.00888. Epub 2022 Aug 18. PMID: 35984037.
Level of Evidence
Level III
Scientific Literature Review
Reviewed By
Shawn Kashef, DPM
Residency Program
Kaiser San Francisco Bay Area
Podiatric relevance:
Transmetatarsal amputations are a common procedure in the podiatric field, with a significant portion of patients having diabetes and peripheral neuropathy. Late development of forefoot ulcers are an unfortunately frequent finding after TMAs, due to a combination of muscle imbalance due to the procedure and neuropathy. There are adjunct procedures that can be performed with the TMA including tendon transfers and Achilles tendon lengthening. The aim of this study was to examine whether prophylactic Achilles tendon lengthening is associated with a reduction in the incidence of forefoot ulcers postoperatively. Secondarily, they take a look at if there are any demographic risk factors for late ulceration and complications associated with prophylactic ATL.
Methods:
A retrospective chart review over a 5 year span from 2015-2020 was performed. 85 feet (83 patients) were included who underwent TMA by 6 different surgeons. 30 feet who had
simultaneous prophylactic ATL procedures. The decision to perform ATL did not require the presence of equinus.
Primary outcome measure - Development of plantar forefoot ulcers after surgery
Secondary outcome measure - Time after surgery that the ulcer developed
Results:
55 cases of TMA alone → 19 (35%) developed forefoot ulceration
30 cases of TMA with prophylactic ATL → 1 (3%) developed forefoot ulceration
Mean time from surgery to ulcer development:
TMA alone: 587 days
TMA with ATL: 695 days
2 (6%) Achilles tendon ruptures reported in the TMA with ATL group vs. 0 in the TMA alone group
9 of the 19 patients without ATL who developed an ulcer developed subsequent osteomyelitis, with 3 (16%) going on to more proximal amputation.
Patients with ulcerations were younger (average 55 years vs. 63 years)
Interestingly, PVD more prevalent in those without ulcerations (46%) than with ulcerations (20%) Other variables such as gender, diabetes, HbA1c level, smoking status, BMI, renal function, and amputation level were not associated with ulceration.
Conclusions:
Adequate offloading is the key to reducing the risk for ulceration. ATL is one of the several ways to decrease pressure to the forefoot after TMAs. The data in this study identified a positive association between prophylactic ATL at the time of TMA and reduced ulceration, with lower rates of proximal amputations. While this procedure shows promising results in the study, there were limitations which include lack of pre-operative equinus assessment and BMI measurements. Adding an ATL as an adjunct procedure has the potential to be beneficial,however one also has to consider that it is an additional procedure which will add to anesthesia and post-operative recovery times, while also having an increased risk of Achilles rupture. Further research investigating specific pre-operative indications for a concomitant ATL would be beneficial to practice guidelines and patient outcomes.