Microvascular Reconstruction in the Revascularised Diabetic Foot: A Perforosome Approach

Background and Introduction: Now there is increasing occurrence of diabetic foot with ongoing epidemic of diabetes mellitus throughout the world. Considerably there is also increase in the critically ischemic diabetic foot which requires timely recognition, timely revascularization and last but not the least timely reconstruction. In this article author describes his perforosomal approach for the microvascular reconstruction in the revascularised diabetic foot. This thoughtful applied anatomical approach is pursued right from the recognition of critical ischemia. It begins with assessment of perforosomes involved by ischemia and subsequently perforosomal directed distal revascularization (PDDR) and then perforosome directed reconstruction. Plastic surgeon coordinates with interventional radiologists or vascular surgeon to pursue direct distal revascularization of all involved perforosomes. Finally this culminated in the perforosomal approach for the reconstruction, which results in shoeable and stable foot or foot residuum in all cases. Altered vasohemodynamics peculiar to the revascularised diabetic foot called “Regional vascular insufficiency” (RVI) also discussed in this article. Aim: Aim of the study is to discern how effective is the microvascular reconstruction (MVR) in healing the recipient site in neuroischemic diabetic foot affected by RVI. Also how effective is PDDR in bringing the healing potential in the ischemia-affected perforosomes of foot. To analyze the complications related to PDDR and MVR. Materials and Method: This is prospective cohort study with level II evidence conducted with 50 (age 44 to 68and M: F ratio 40:10) critically ischemic diabetic foot patients (ABI <or= 0.7) with no healing potential. All had undergone PDDR followed by microvascular reconstruction during March 2011 to March 2016. All patients were followed for on average period of 18 months post reconstruction. The outcomes were analyzed in terms of, averagelatency period (between the revascularization and reconstruction contributed by regional vascular insufficiency) as a measure of effectiveness of PDDR, and then factors like ambulation capabilities attained, length of hospital stay and rate of recurrence of ulcers as the measure of effectiveness of microvascular reconstruction (MVR). All patients also underwent many adjuvant procedures (internal offloading) as an integral part of MVR. Complications related to PDDR and MVR are also analyzed. Results: Fifty patients admitted with critically ischemic diabetic foot were included this study based on the selection criteria. Descriptive and life table statistical analysis is used in this study. All of them undergone PDDR (46 had angioplasty; 2 had angioplasty and bypass-hybrid procedure; 2 had bypass alone down to foot). No patients in angioplasty group had any procedural complication except in one case in the hybrid group and one in angioplasty group had transient renal parameters rise. One in distal bypass group had bypass wound infection treated surgically and recovered. One perforator/propeller suffered partial epidermolysis treated conservatively. The average Latency period in the bypass group is 28 days, hybrid procedure group is 28.5 days and angioplasty group is 18.5 days. Results are stratified in to 4 groups. In group one (above hip perforosome – thoraco dorsal artery muscle perforosome (TDAP), thirty one patients had MVR with latissimus dorsi thoracodorsal artery muscle perforosome with split thickness skin graft. In this group there is 2 cases of arterial insuffiency successfully revised on 1st POD. There was no other complication in this group. In Group two (above hip perforosome-radial forearm arm flap), six patients had MVR with radial forearm flap. No complications occurred in this group. In-group three (below hip disease free perforosome reconstruction), four patients had MVR with vastus lateralis perforator flap as the angiogram revealed healthy profunda femoris vessels in these cases. One case in this group required revision for venous insuffiency with vein graft on the 1st POD and flap salvaged successfully. Other three patients of this group had MVR with free Gracilis flap and one patient received contralateral medial plantar artery perforosome. Dorsum defect (1 case) and great toe stump raw area (4 cases) are treated by arcuate artery perforator flap and first dorsal artery perforator flap respectively in the fourth group (Perforator/propeller flaps group). All MVR flaps survived in this group except one case there was superficial epidermolysis. In the post PDDR phase 36 cases had calcaneal raw area (perforosomes supplied by calcaneal branch of peroneal and posterior tibial vessels are involved) and all are treated by latissimus dorsi thoracodorsal vessel muscle perforosome with skin graft. It took 2.5 months on average to assume bipedal walking in this group. Forefoot raw area was present in the post PDDR phase in11 cases. It took 2 months on average for these patients to assume bipedal walking. One case of modified pirograffs amputation stump raw area had undergone after PDDR, MVR with vastus lateralis perforator flap. This patient assumed bipedal walking with prosthesis on 70th postoperative day. All perforator flaps resumed bipedal walking on average 26 days from the time of MVR. Only one case of Lattisimus dorsi required thinning performed at 60th postoperative day and this patient started bipedal ambulation on 4th month following MVR. There was no periprocedural mortality in this study. Flap survival rate is 100% in our study. Overall recurrence ulceration rate is 6%. Discussion: When compared to available other similar related studies author had better results in terms of duration of hospital stay and period after MVR before assuming bipedal ambulation and less latency periods because of PDDR and subsequently with perforosomal approach of MVR. Ulcer recurrence rate is also comparable to other related studies. Conclusion: This perforosomal approach makes a definitive difference in salvaging the critically ischemic diabetic foot.