Drop foot,a rare complication following Müller's phlebectomy

Case report

A 43-year-old woman presented with varicose veins. Eight years ago, our patient underwent bilateral surgical stripping of the great saphenous vein and the right small saphenous vein. Furthermore, she was treated with compression sclerotherapy two and three years earlier. Now she returned with recurrence of superficial visible varicose veins of both legs. The varicose veins did not cause symptoms other than poor cosmetics. On clinical examination both legs showed some reticular varicose veins and on the dorsolateral side of the right upper leg up to shortly below her knee there were convoluted visible varices. Duplex examination was performed and confirmed the clinical diagnosis. We decided to proceed with ambulatory surgical phlebectomy using the Müller technique of the right leg. We performed local anaesthesia (non-tumescent) with approximately 15 cm³ lidocaine 1%. Immediately after phlebectomy the patient noticed weakness of the right foot without neurological pain. She had a right foot drop. Basic neurological examination did not reveal any other neurological problems. Since we concluded that the drop foot was most probably caused by infiltration of the common peroneal nerve (CPN) by the anaesthetic, we decided to wait and see. The drop foot disappeared after several hours spontaneously without therapy.

Discussion

Ambulatory phlebectomy is a satisfactory procedure for the treatment of most patients presenting with varicose veins. Its clinical as well as cosmetic results are very gratifying. ¹ Complications arising from ambulatory phlebectomy are quite rare but do exist. ² In a review of 1000 consecutive cases of ambulatory phlebectomy, ¹ the two most frequent complications were blister formation and localized thrombophlebitis. Ramelet ² concluded that minor inconveniences are common, depending partially on surgical indications, operator's skill and experience. Adequate training allows one to minimize untoward reactions.

The occurrence of a foot drop quickly after the procedure indicates injury to either the CPN or a more proximal focal lesion of this nerve. This can be from the surgery, anaesthesia or compression dressing. In the latter case the symptoms do not arise immediately. If the nerve is damaged by surgery, the symptoms will not recover. In several hours the foot drop recovered. In our case there was a transient nerve blockage, a so-called paresis, caused by infiltration of anaesthesia.

The CPN or fibular nerve derives as a part of the sciatic nerve. It runs behind the femur from the buttock to the lower thigh where it divides into the CPN and sciatic nerve. The CPN then descends along the lateral side of the popliteal fossa to the head of the fibula. It winds round the head of the fibula and divides into the superficial peroneal nerve and the deep peroneal nerve. The CPN is most susceptible to damage where the nerve winds round the head of the fibula (Figure 1). The deep peroneal nerve is responsible for dorsiflexion the foot. Injury to this branch produces weakness or paralysis of the muscles responsible for these actions. ² OPEN IN VIEWER

In our case the anaesthesia infiltrated around the fibula head caused temporary blockage of the CPN. During treatment it is important to be aware of this anatomy. When operating in the field of the lateral knee, the area around the fibula head should be avoided or done with extreme caution. It is therefore important to test the mobility of the foot before the patient stands up. ³ Sclerotherapy could be a good alternative therapy in this area.

Conclusion

Ambulatory phlebectomy, as described by Müller, is a remarkable aesthetic and effective technique for definitive removal of varicose veins and complications are rare. We describe a case in which the patient had a temporary foot drop caused by anaesthetic infiltration. In treating varicose veins using the technique of Müller, care must be taken to prevent permanent nerve damage or temporary anaesthetic blockage of the CPN near the fibular head.