The extended lateral approach is widely applied for intra-articular calcaneal fracture ORIF and offers advantages of achieving adequate fracture reduction with the risk of wound-healing complications and infection . An L-shaped lateral incision is made to expose the calcaneus, but the corner of the incision is the most likely site of wound healing complications, such as necrosis. Skin necrosis, wound dehiscence, and plate exposure most often appear in this area, because there is less subcutaneous tissue under the lateral calcaneal flap. Blood flow to the lateral calcaneal flap is primarily supplied by the lateral calcaneal artery (LCA), and complications in wound healing, such as ischemia of the lateral calcaneal flap, can arise from damage to the LCA. Borrelli et al. concluded that, based on the position of the LCA, it is vulnerable to injury caused by the vertical incision in the lateral approach .
Smoking has a detrimental effect on the healing of wounds. Smoking causes blood vessels to contract, thus reducing blood supply to the extremities, with decreases in the contractility of vessels, blood flow rate, and efficiency of oxygen transportation. These negative effects are reversible . The literature generally confirms that nicotine abstinence for 4–8 weeks preoperatively is advantageous and post-operative complications may be reduced if patients refrain from smoking for 10 days after surgery [15, 16]. In our study, the six smoking patients were asked to stop smoking before the operation and to abstain for another 2 weeks postoperatively. The flaps in all six patients healed uneventfully.
Diabetes was considered as a significant independent risk factor for wound complications . Diabetes can impede wound healing and predispose patients to infection through ischemia secondary to microvascular abnormality. In this study wound complication after ORIF occurred in all four diabetic patients. During the flap operation period, the blood glucose levels were maintained below 10.0 mmol/L in all four diabetic patients by insulin injection. Finally, the flap survived.
When skin flap necrosis occurs at the corner of the Extensile Lateral Approach , local wound care, debridement, changing dressings, antibiotics and skin flap transplantation should be attempted, in that order, with a favourable outcome being largely dependent on early diagnosis and treatment . Herscovici et al. reported that debridement of all necrotic tissue and changing dressings once a day using thick povidone iodine gauze often resulted in a good outcome . However, if the necrotic area results in implant exposure, skin flap transplantation might be needed. A reversed sural nerve flap is most frequently used because of its rich blood supply and the simplicity of the operation . The most common complication encountered with the reversed sural type of flap is venous congestion which may result in partial- or full- thickness flap necrosis . Transfer of a free flap has also been reported to cover a defect in this area . This technique requires specialized microsurgical training and is best performed in patients who are able to withstand prolonged general anesthesia . There is also morbidity at the donor site and later shoe-fitting problems because of a bulky contour. The abductor digiti minimi (ADM) flap can be used for small defects at the corner of the Extensile Lateral Approach. CL Wang et al reported that they used the abductor digiti minimi muscle flap as a muscular plug between the wound and the plate after ORIF of calcaneus fractures  . However, loss of the ADM muscle may result in lack of plantar lateral padding, which may result in discomfort. In this study, we reported a local random pattern flap for coverage of the skin necrotic area with implant exposure. Local random pattern flaps are flaps whose success depends on a length-to-width ratio (1.5:1) with no specific blood flow at their base. Attinger et al. used a local muscle flap for the treatment of hardware exposure . In our cases, we used a local random pattern flap to cover the hardware exposure. The benefits of this flap include a similar tissue composite of the hardware exposure area, no specialized microsurgical training, and easy for surgeons to operate.
However, our technique has a limitation. Before applying the local random flap for hardware exposure, we needed to collect some wound specimen for culturing to indentify pathogens. If the result was positive which implied that there was a deep infection at the surgery site, the local random flap was not recommended. Thus, in this study, the wound specimen was collected and cultured to indentify pathogens before operations. The local random flap was applied to the patients with negative results.