Surgical Outcomes of Spiral Vein Wrapping Flaps for Painful Neuromas: A Case Series Analysis

Introduction

Neuroma formation, resulting from abnormal nerve growth after injury, is a debilitating condition that can lead to significant morbidity and have a considerable socioeconomic impact [1]. Surgical intervention often becomes the preferred treatment, owing to the limited success of non-surgical approaches [1,2]. Advancements in surgical interventions have introduced more active approaches aimed at guiding and controlling the nerve regeneration process, thereby reducing the risk of neuroma formation and associated pain. Recently, neurolysis and neurectomy seem to be the most practical and frequently used techniques to treat neuroma cases. However, some studies report that the surrounding environment can affect painful neuroma formation. This suggests that neuroma management requires a physical barrier, to provide protection from irritants [2,3].

Currently, there is no consensus on the optimal method for surgery of painful neuromas; however, tubulation of nerve ends after neuroma resection has been shown to decrease recurrence and myofibroblast growth [2,3]. Techniques like nerve capping, in which a synthetic or biological material is placed over the nerve end, aim to contain the regenerating axons within a structured environment, potentially reducing chaotic growth patterns. From a biological perspective, these active surgical techniques leverage the body’s natural regenerative processes by providing a controlled environment for nerve regrowth. This approach aligns with the understanding that neurons exhibit plasticity, and their growth can be influenced by external guidance, whether through physical structures like grafts or through adjacent biological signals [1–4].

One method of tubulation is nerve wrapping with the use of a vein. The concept of nerve wrapping with a vein was introduced by Masear et al in 1989 as a means to prevent nerve scarring [4]. This method is easy and inexpensive; however, there is still a lack of reports regarding the outcome of the use of vein wrapping following neuroma excision and sural nerve grafting. Here, we present 4 cases of neuromas that were treated with neuroma excision followed by nerve wrapping using a vein autograft.

Case Report

SURGICAL PROCEDURE:

In our surgical technical notes, we present our fourth case: a stump femoral neuroma following transfemoral amputation. All patients underwent an identical procedure, except for the suturing of the distal part of the nerve after neuroma resection for neuroma incontinuity.

PATIENT POSITION:

The patient position was supine, with the knee flexed at 30 degrees and the leg internally rotated, facilitating access to the posterolateral crural area. A tourniquet was applied to the femur region, with pressure ranging from +350 mmHg, with partial deflating of the tourniquet to create vascular bulging, aiding exploration and identification during surgery.

SURGICAL TECHNIQUE:

After identifying the neuroma location, the incision was made based on the previous scar, with an additional 2 to 3 cm of extension proximally and distally if needed (Figure 2A). Careful dissection freed the nerve from surrounding tissues and was followed by circular neurolysis. To prevent nerve devascularization, the epineurium was preserved, and longitudinal epineurotomy ensured it remained with the neural fibers. The nerve length was measured to determine the required length for vein wrapping.

Following neuroma excision, vein wrapping involved using the saphenous parva vein, approached from the anterior malleolus and followed proximally (Figure 2B, 2C). After tying proximal and distal ends, the veins were removed and longitudinally cut. The donor vein was harvested at a length approximately 4 to 5 times that of the nerve it would encase, and it was secured with nylon 6/0 sutures. Typically, 3 stitches per spiral were used to complete a full 360-degree wrap, ensuring there were no gaps in the stitching that could expose the nerves within the veins (Figure 2D).

POSTOPERATIVE MANAGEMENT:

A 4-inch elastic wrap was applied to the donor leg for 7 to 10 days. Mobilization began with isotonic and isometric movements, and weight-bearing was allowed, based on pain tolerance. Full activity was usually achieved within 3 to 4 weeks.

For extremities receiving the graft, a 4-inch elastic wrap was applied after the procedure, and active range of motion exercises began immediately. Stitches were removed within 10 to 14 days, followed by scar and tendon tissue mobilization. Pain management included transcutaneous nerve stimulation, local corticosteroid injections, and oral medications, such as nonsteroidal anti-inflammatory drugs. Narcotic analgesics were avoided if possible, due to the chronic nature of nerve tissue scarring, requiring long-term safe treatment.

CLINICAL OUTCOMES:

At the patients’ 1-year follow-up after surgery, we assessed the neuroma pain score and Weber 2-point discrimination. Any complications were noted during the follow-up, such as surgical site infection and persistent or recurrent neuropathic pain suggesting neuroma. At the time of follow-up, all wounds had healed, with no signs of infection or inflammation found, and no disturbing pain or discomfort was experienced. All patients were evaluated at the same interval, 1 year after surgery. At this point, their pain was minimal, and they no longer required pain management therapy (Table 2).

Discussion

OVERVIEW OF NEUROMA AND NON-SURGICAL MANAGEMENT:

Neuroma is the most common complications of peripheral nerve injury, resulting from extremity trauma and amputation [5]. Neuroma can cause chronic neuropathic pain, imposing not only a physical burden but also a psychological one, as it can interfere with the patient’s work and quality of life. Currently, there is no consensus on the best management for painful neuroma cases [3]. Some commonly used non-surgical therapies include massage, desensitization, and the use of analgesic and anti-neuropathic agents, such as gabapentin, and antidepressants, such as tricyclic antidepressants and selective serotonin reuptake inhibitors [6]. However, surgical therapies are considered to have better clinical outcomes and are an option for patients who have not responded to conservative management for at least 6 months [3,6]. In our cases, all patients underwent conservative treatment for 6 months; however, the neuropathic pain was still persistent. Conservative treatment yields poor results, with a high unresponsive rate ranging from 60% to 70%. This finding further supports surgery as a salvage treatment.

SURGICAL MANAGEMENT OF NEUROMA:

Several procedures can be used as surgical therapy for neuroma; however, a systematic review by Poppler et al in 2018 concluded that no differences were found in outcomes between various operating procedures [3]. The main principle of surgical management is neuroma resection; if the gap is too large for end-to-end suture, nerve grafting can be performed. In cases of end neuromas, nerve endings can be transferred to other tissues, such as muscles, bones, or veins, to facilitate a more physiological healing process [6]. When the surgical procedure involves only neuroma resection without additional procedures, there is a refractory rate of 30% and a recurrence rate of 65% [5]. Therefore, surgical resection along with additional procedures aimed at facilitating the physiological process of nerve healing need to be performed to improve outcomes.

VEIN WRAPPING TECHNIQUE:

One method of tubulation that can be used is vein wrapping, which has been shown to decrease the proliferation of myofibroblasts [3]. The vein wrapping technique was proposed for repairing peripheral nerve damage [2]. The biological mechanism underlying the success of the vein wrapping technique in nerve repair lies in its facilitating nerve regeneration. This technique aims to enhance nerve graft regeneration by creating a biological chamber at the anastomosis site, collecting axoplasmic fluid from the transected nerve ends. Isolation from the site of the anastomosis can also isolate the inflammatory process [2]. The vein wrapping technique also can create a protective, supportive environment that promotes organized nerve regeneration, minimizes harmful scarring, and reduces the risk of neuroma formation [1,2]. In this report, we used a sural vein autograft, considering its size and compatibility with sural nerve autografts.

Results from previous studies showed better recovery, compared with controls. Our study yielded similar findings, in which the use of nerve wrapping on end neuromas or neuromas in continuity after resection demonstrated clinical improvement, with no recurrence during our follow-up period. Another study by Moon et al involved vein-wrapped repairs harvested from the jugular vein for the reconstruction of recurrent pharyngeal nerves in patients after thyroid resection [2]. After 3 months, vocal cord fixation on the median was observed, but good tension was maintained during phonation. Noaman et al stated that results from nerve wrapping, either partially or completely, were superior to those of non-wrapped repairs, as confirmed by functional sensory and motoric measurements and electromyography [2,3,7] (Table 3).

COMPARISON WITH OTHER WRAPPING MATERIAL:

Several options of organic and synthetic materials can be used as nerve anastomosis barriers. However, the use of a vein has several advantages. The vein is easily accessible and always available on the same operating field, thus preventing donor site morbidity. It is also easily dilated, allowing adjustment to the size of a nerve, even for larger sizes. Moreover, veins are less allergenic and less expensive than synthetic materials. Veins possess stretchability, which can protect the site of the anastomosis due to their biologically inert, biodegradable, and non-compressive properties, thereby enhancing nerve conduction [2,7]. Veins can be used to protect nerve anastomosis through wrapping or sheathing, which are both equally effective in preventing neuroma formation. Additionally, the patient’s prognosis varies based on factors such as reconstitution time, age, type of nerve involved, mechanism of trauma, and degree of fibrosis formed [7].

Despite the good clinical results from the spiral vein wrapping flap that we reported, our study had several limitations, including a small sample size, the lack of a control group, and a short follow-up duration. Future research should aim to validate our findings with a larger sample size and a longer follow-up period.

Conclusions

Neuromas of the peripheral nerves are mentally and physically incapacitating. Vein wrapping after nerve grafting techniques is easy and available and shows satisfactory results, with minimal pain outcomes and no necessity of pain management therapy.