Nerve Entrapment Syndromes of the Lower Extremity Treatment & Management

Updated: Oct 15, 2019
  • Author: Minoo Hadjari Hollis, MD; Chief Editor: Thomas M DeBerardino, MD  more...
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Treatment

Pharmacologic and Physical Therapy

Iliohypogastric or ilioinguinal nerve entrapment

Treatment of iliohypogastric or ilioinguinal nerve entrapment may include local injection of an anesthetic, oral or topical medications, or physical therapy.

Among the oral agents that may be considered are antiseizure medications (eg, gabapentin, carbamazepine, and lamotrigine), nonsteroidal anti-inflammatory drugs (NSAIDs), tricyclic antidepressants (TCAs; eg, amitriptyline and doxepin), and tramadol; capsaicin cream or topical lidocaine may also be useful. With physical therapy, cryotherapy or a transcutaneous electrical nerve stimulation (TENS) unit may be tried.

Genitofemoral nerve entrapment

Anesthetic nerve blocks are diagnostic and therapeutic for genitofemoral nerve entrapment. Avoidance of aggravating activities should be emphasized. Treatment may also consist of antiseizure medications (eg, gabapentin, carbamazepine, or lamotrigine), as well as TCAs (eg, amitriptyline and doxepin). Other medications include capsaicin cream, topical lidocaine, NSAIDs, and, possibly, tramadol. A trial with a TENS unit may also be beneficial.

Femoral nerve entrapment

In less severe cases, treatment of femoral nerve entrapment may be purely symptomatic. Quadriceps weakness may be treated with a locking knee brace to prevent instability, and the patient may require an assistive device for walking. Good recovery is achieved in as many as 70% of patients and may take as long as 1 year. Recovery may occur even when the injury is fairly severe, as determined by electrodiagnostic testing and physical examination. Patients with severe axonal loss have some recovery of function, though it is usually incomplete.

Lateral femoral cutaneous nerve entrapment

Treatment of lateral femoral cutaneous nerve entrapment may include injection of local anesthetic agents. A steroid can also be used to prolong the effects of the local anesthetic and reduce inflammation. Oral medications, such as NSAIDs, antiseizure medications (eg, gabapentin), TCAs, and tramadol, may be used, as may capsaicin cream and topical lidocaine.

It is also important to instruct patients regarding ways of preventing further irritation of the nerve. These may include avoidance of hip extension, prolonged standing, and compressive garments. The use of ice and a TENS unit may also be helpful.

Saphenous nerve entrapment

Saphenous nerve entrapment in the adductor canal usually is treated conservatively by injecting an anesthetic (with or without a corticosteroid) at the point of maximal tenderness (usually 10 cm proximal to the medial femoral condyle). The injection may have to be repeated periodically. Avoiding aggravating activities and using proper body mechanics will also be helpful. If this approach fails, surgical intervention may be needed.

Obturator nerve entrapment

For anterior obturator nerve entrapment, treatment may consist of electrical stimulation of the adductor and hip flexor muscles, stretching, and massage. These modalities, however, typically have not been successful in resolving this condition if it is not recognized early.

Posterior tibial nerve entrapment

Compression of the branches of the posterior tibial nerve is a common cause of refractory heel pain and is the most common compression neuropathy seen in the foot and ankle region. Nonoperative management of compression of the posterior tibial nerve involves relief of the source of external compression (if any), use of medication, and correction of weightbearing deformities.

Treatment of posterior tibial nerve entrapment (tarsal tunnel syndrome) is directed toward the underlying etiology of neural compression. Nonoperative options can include the use of NSAIDs (in cases associated with inflammation), aspiration of underlying cystic lesions, and control of edema and varicosity. Medical treatment of underlying systemic conditions is helpful in the indicated situation. The use of antineuritic medications (eg, gabapentin and, occasionally, TCAs) has also been shown to alleviate symptoms in many patients.

At times, a trial of immobilization with the use of casts or walking boots is indicated. Orthotic management is indicated in patients with proximal entrapment and alignment or postural abnormalities causing chronic traction or compression trauma to the nerve. In patients with distal entrapment and associated heel pain, the use of accommodative orthotics with a relief area in the anterior heel pad (ie, under the posterior tibial nerve) is usually helpful.

Patients with flatfoot may benefit from semirigid University of California at Berkeley Laboratory (UCBL)-type orthotic devices with a deep heel cup to minimize weightbearing traction on the nerve.

Common peroneal nerve entrapment

Initial nonoperative treatment of common peroneal nerve entrapment should focus on maximizing mobility and function. In addition, the cause of nerve compromise or compression should be corrected to reduce further nerve damage.

NSAIDs or oral corticosteroids may be useful in cases where an inflammatory process is present. Corticosteroids injected into the affected region may reduce swelling and pressure on the nerve in some cases. Symptomatic pharmacologic treatment may consist of TCAs (eg, amitriptyline) or neuroleptic medications (eg, gabapentin and carbamazepine).

A brace (ankle-foot orthosis [AFO]), splints, or orthopedic shoes may control the abnormal dynamics at the ankle and provide dorsiflexion assistance for a more ideal gait pattern during nerve recovery. In-shoe orthotics may be helpful in certain instances, as in the correction of a biomechanical malalignment in gait (eg, in patients with severe flatfoot or cavus foot).

Many authors have reported spontaneous recovery; therefore, initial nonoperative management for a minimum of 3-4 months is recommended for idiopathic cases and for those suggestive of neurapraxia.

Superficial peroneal nerve entrapment

Vague and diffuse symptoms can create a diagnostic and therapeutic challenge for the treatment of superficial peroneal nerve entrapment. The use of multiple diagnostic modalities, including repeat examinations, selective injections, and electrodiagnostic studies, is required. Treatment of the underlying cause should be undertaken, as should release of the entrapped nerve and excision of existing neuromas.

Nonoperative options include the use of NSAIDs combined with relative rest, physical therapy for strengthening of muscles in cases of associated weakness or recurrent ankle sprains, and elimination of predisposing or triggering factors. Aids, such as braces, can be used to avoid recurrent ankle sprains. In-shoe orthotic devices may be helpful in certain instances, such as the correction of a biomechanical malalignment in gait for patients with severe flatfoot or cavus foot.

At times, injection of steroids plus lidocaine near the site of involvement in the lower leg can reduce symptoms and serve as a diagnostic tool in confirming the zone of nerve compression. The use of antineuritic medication (eg, gabapentin) can also be helpful in reducing or sometimes eliminating symptoms, particularly in cases associated with complex regional pain syndrome (CRPS). In these cases, combination treatment with medication, physical therapy, and local and sympathetic nerve blocks may be required.

Deep peroneal nerve entrapment

Nonsurgical care of patients with deep peroneal nerve entrapment most importantly involves patient education to eliminate predisposing factors. For example, padding of the tongue of the shoe, the elimination of shoes with laces, or the use of alternative lacing methods, as well as the avoidance of high heels, may be sufficient to resolve symptoms.

Physical therapy is useful for strengthening the peroneal muscles in cases associated with weakness and in individuals with chronic ankle instability; physical therapy may also improve symptoms.

In-shoe orthotic devices are helpful for certain applications, such as for correction of a biomechanical malalignment in gait (eg, in patients with severe flatfoot or cavus foot).

NSAIDs and antineuritic medication may be helpful as adjuncts to other treatment modalities. Injection of steroids plus lidocaine near the site of involvement can reduce symptoms in some individuals.

In addition, consideration should be given to a metabolic workup to rule out thyroid dysfunction and diabetes in select individuals. Further workup may be necessary to rule out lumbar radiculopathy.

Interdigital neuritis

If interdigital neuritis (also referred to as Morton neuroma, Morton metatarsalgia, interdigital neuroma, or interdigital nerve compression) is detected early, conservative measures may be reasonably successful. About 20-30% of patients achieve adequate relief with nonoperative management. This may be accomplished by eliminating or minimizing the external sources of compression or stretch on the interdigital nerve.

Extra-wide shoes and low heels, as well as the placement of a small metatarsal pad just proximal to the heads of the central three metatarsals, may reduce symptoms by increasing the intermetatarsal space, elevating the metatarsals and the intermetatarsal ligament, and reducing the likelihood of neural irritation. Accommodative orthotic devices with built-in metatarsal pads may at times be helpful, especially in patients with alignment abnormalities. Stiffer, rocker-soled shoes may be useful.

NSAIDs may relieve acute pain and inflammation. If NSAIDs provide insufficient relief, a local anesthetic injection can also relieve pain and may help to confirm the diagnosis of interdigital neuritis.

Mann et al did not find corticosteroid injections to result in predictable or lasting relief. [50] Rasmussen et al reported initial pain relief in 80% of patients who received a single corticosteroid injection [51] ; however, 47% of the 41 feet studied ultimately required surgical excision, and most of the remaining 53% had residual symptoms.

In addition, corticosteroid injection for intermetatarsal neuroma has been associated with a number of complications, including plantar fat-pad atrophy, skin depigmentation, hyperpigmentation, and telangiectasias. Fat-pad atrophy can result in metatarsalgia and gait impairment.

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Surgical Intervention

Iliohypogastric or ilioinguinal nerve entrapment

When conservative measures are not successful in treating entrapment of the iliohypogastric or ilioinguinal nerve, surgical excision may result in relief of pain with few potential complications (eg, possible neurolysis of the nerve in refractory cases). Surgical excision is more invasive but has had good outcomes in several reports. Krahenbuhl et al reported an endoscopic approach. [52]

Genitofemoral nerve entrapment

If conservative treatment of genitofemoral nerve entrapment fails, surgical excision of the nerve is the treatment of choice. A transabdominal approach to the nerve has been described as having satisfactory results. [53, 54] Complications of this procedure include hypoesthesia of the scrotum or labium majus and of the skin over the femoral triangle, as well as loss of the cremasteric reflex; this usually does not result in notable morbidity. According to Harms et al, an extraperitoneal approach should result in fewer operative complications. [55]

Femoral nerve entrapment

In many cases, as noted (see above), treatment of femoral nerve entrapment may be based on symptoms only. In some instances, it may be more invasive and include surgical intervention, depending on the severity of the injury.

Lateral femoral cutaneous nerve entrapment

If conservative or pharmacologic treatment of lateral femoral cutaneous nerve entrapment is not helpful, surgical exploration may be required. This may include transection of the nerve or decompression with or without neurolysis. [56, 57] Anatomic variations of the nerve and neuromas can occur and may lead to recurrence. [58]

Saphenous nerve entrapment

If nonoperative therapy for saphenous nerve entrapment fails, surgical decompression may be needed. In patients who have sustained a direct blow to the medial knee and are experiencing persistent medial knee pain despite conservative trials for treatment, a neurectomy or neurolysis of the infrapatellar branch may be helpful.

Obturator nerve entrapment

For athletes, surgery is the preferred treatment when clinical features of obturator neuropathy and denervation on electromyography (EMG) are observed. The surgical procedure involves dividing the fascia over the pectineus and the adductor longus and dissecting the space between the two muscles to reveal the anterior branch of the nerve beneath a thick fascia. This fascia is divided along the line of the nerve, and the adductor longus−pectineus junction is closed loosely.

Posterior tibial nerve entrapment

Surgical release is indicated for refractory cases of posterior tibial nerve entrapment (tarsal tunnel syndrome) and for most cases with space-occupying lesions. In patients with proximal or distal posterior tibial nerve entrapment, this has an 80-90% likelihood of improving or resolving the symptoms.

The location of the release is partially dependent on the location of entrapment. Most cases, however, call for a full release of the posterior tibial nerve and of the lateral plantar nerve and its branches. The skin is marked for the proposed skin incision. For proximal entrapment, the incision is started 2 cm proximal to the medial malleolus, approximately halfway between the medial malleolus and the Achilles tendon. It is extended distally and plantarly, directly superficial to the course of the posterior tibial nerve.

A full release includes release of the flexor retinaculum overlying the nerve, starting proximal to the medial malleolus and moving distally to include release of the deep fascia of the abductor hallucis. The neurovascular bundle is posterior to the flexor digitorum brevis. Typically, medial and lateral plantar nerves branch at the level of the medial malleolus. It is best to identify the posterior tibial nerve proximally and follow it distally.

All sources of potential impingement are released from the medial and lateral plantar nerves. The medial calcaneal branches are quite variable and should be watched for closely. A large number of vessels are encountered routinely, and some crossing veins may need to be ligated.

It is important to ensure full release of the lateral plantar nerve and its first branch. The superficial and deep fascia of the abductor hallucis is released as the nerve is followed distally. Partial release of the plantar fascia is usually necessary for full visualization. No consensus exists in the literature about the necessary amount of plantar fascia release.

The extent of the plantar fascia release may be dictated partially by the arch height, and a full release may be indicated in patients with a cavus foot, whereas a minimal release could be considered in patients with flatfoot. Retraction of the abductor hallucis and the flexor digitorum brevis allows good visualization of the lateral plantar nerve and its first branch. The usual course of the lateral plantar nerve is just anterior to the heel pad.

As the lateral plantar nerve is followed, any compressive fascial bands are cut. The fascia of the quadratus plantae is also identified and released if it is noted to cause any compression by the medial edge of the quadratus plantae fascia on the first branch of the lateral plantar nerve. In cases of associated space-occupying lesions, the incision is modified as necessary for complete excision of the tumor.

Bipolar electrocautery and surgical loupe magnification are necessary for optimal visualization. Handling of the nerve should be minimized. Often, large varicosities are present that should be considered part of the underlying compressive etiology. Care must be taken to avoid injury to these large vessels, which can compromise visualization and can cause intraoperative and postoperative bleeding and postoperative scarring. The medial plantar nerve is fully released. The tourniquet is released before closure to ensure that no major bleeding occurs.

The plantar skin incision is reapproximated without the use of subcutaneous sutures. Reapproximating the subcutaneous tissues and the skin closes the medial segment of the incision. A bulky soft-tissue dressing is then applied, and range-of-motion exercises are encouraged.

Postoperatively, the patient with a distal release of the nerve and full plantar fascia release is kept on nonweightbearing status for 4-6 weeks. In patients with lesser releases of the plantar fascia, weightbearing is protected until pain and swelling are improved and the wound is closed, which takes approximately 2-3 weeks. Complete release is indicated in most cases of posterior tibial nerve entrapment, including those with distal entrapment of the nerve branches (usually associated with intractable heel pain).

If entrapment of the medial plantar nerve is suspected, the incision beyond the medial malleolus curves toward the plantar aspect of the medial navicular, and full release is performed to the knot of Henry.

In a report of operative results from patients with recalcitrant heel pain, Baxter and Thigpen performed a full release of the lateral plantar nerve and its branches with minimal or no plantar fascia release. [5] The two most common areas of compression were noted at the sharp fascial edge of the abductor hallucis and at the medial ridge of the calcaneus where the nerve passes over it beneath the tuberosity or origin of the flexor brevis and plantar fascia.

Of the 34 heels that were operated on in this study, 32 had good results and two had poor results. [5] Most patients could detect improvement during the first or second postoperative day. Anti-inflammatory medication and orthosis use were continued postoperatively.

Watson et al reported good-to-excellent results in 84% of patients who underwent distal tarsal tunnel release and partial plantar fasciotomy. [59] Bailie and Kelikian reported that 84% of their patients in the noncompensation group were very satisfied or moderately satisfied with the outcome. [60] They also reported better satisfaction in patients with nontraumatic etiology than in others.

Sammarco and Chang, reporting on 108 ankles with posterior tibial nerve entrapment, found that patients with symptoms lasting less than 1 year had significantly better postoperative scores than did patients who had symptoms for more than 1 year before surgery. [22] They did not observe an effect of trauma on the outcome of surgery, and they noted that improvement was predictable even when a space-occupying lesion was not identified at surgery.

In one study, revision tarsal tunnel surgery was performed on 44 patients (two bilaterally), including the following components [61] :

  • Neurolysis of the tibial nerve in the tarsal tunnel and of the medial plantar, lateral plantar, and calcaneal nerves in their respective tunnels
  • Excision of the intertunnel septum
  • Neuroma resection as indicated

A painful tarsal tunnel scar and a painful heel were treated by resection of the distal saphenous nerve and resection of a calcaneal nerve branch, respectively.

Patient-satisfaction ratings in this study were 54% excellent, 24% good, 13% fair, and 9% poor. [61] Prognostic indicators of poor results were coexisting lumbosacral disc disease and neuropathy. The authors noted that an approach related to resecting painful cutaneous nerves and neurolysis of all tibial nerve branches at the ankle may offer hope for relief of pain and recovery of sensation for the majority of patients in whom previous tarsal tunnel surgery has failed.

Common peroneal nerve entrapment

Surgical decompression of the nerve and excision of the offending lesion are indicated in cases of nerve compression due to external causes, such as those associated with intraneural or extraneural tumors or masses.

Löwenstein et al recommend early surgical treatment in cases involving intraneural ganglion cysts, in order to minimize neural invasion (which may cause irreversible axonal injury and foot drop). [62] In cases in which severe paresis and muscle atrophy are present, surgical exploration may also be warranted, especially if electrodiagnostic evidence of active motor axonal degeneration is present.

In one of the largest studies of patients with idiopathic peroneal nerve entrapment, Fabre et al reported on 62 patients who were treated with operative decompression of the common peroneal nerve. [63] The postoperative recovery of motor function was good in 87% of those who had sensory and motor involvement preoperatively. All seven patients who had peroneal nerve entrapment of known etiology also demonstrated postoperative improvement.

On the basis of these results, the authors recommended open decompression of the peroneal nerve between the third and fourth months if symptoms persist or recovery is incomplete, even if the patient has only sensory symptoms that have been substantiated by electrophysiologic studies. [63]

The procedure involves a curved incision about the lateral knee, following the course of the nerve. The nerve is found initially posteromedial to the biceps femoris. It is tracked distally to where it branches to the deep and superficial branches. The nerve is released fully by initially separating the lateral septum between the peroneus longus and soleus aponeurosis, retracting the peroneus longus medially, and fully dividing the superficial and deep portions of the fibrous arch. Any sites of entrapment or compression along this route should be released.

Nerve grafting may be warranted in severe cases in which the nerve is structurally damaged or severed.

Superficial peroneal nerve entrapment

Surgical decompression may be indicated in cases of superficial peroneal nerve entrapment that is refractory to nonoperative options. This can include release of the nerve at the lateral leg for surgical decompression with partial or full fasciotomy. Some authors have also advocated fasciectomy in select cases. Neurolysis generally is not indicated, because it has not been shown to improve outcome.

Styf and Morberg reported that 80% of their patients were free from symptoms or satisfied with the result after decompression of the superficial peroneal nerve. [64] Three of 14 patients underwent local fasciectomy as well.

Styf reported on the use of fasciotomy and neurolysis to treat entrapment of the superficial peroneal nerve in 24 legs (21 patients). [39] Nine patients were satisfied with the result, another six had improvement but were not satisfied because of residual limitation of athletic activity, three had unchanged conditions, and one had a worsened condition. Conduction velocity in the superficial peroneal nerve increased postoperatively, though the change was insignificant.

In five of the patients, the nerve had an anomalous course, and in 11, fascial defects were present over the lateral compartment. [39] The author concluded that operative decompression of the superficial peroneal nerve produces cure or improvement in about 75% of cases but that it is less effective in athletes than in others.

Sridhara and Izzo reported complete symptomatic relief after surgical decompression. [65] Johnston and Howell reported dramatically relieved pain after release and anterior transposition of the nerve in patients who had had neuralgia after inversion ankle sprain. [66]

The surgical procedure to release the superficial peroneal nerve at the anterolateral leg involves preoperative determination and marking of the location of maximum tenderness and, if present, lateral muscle herniation. The procedure is performed with magnifying loupes and a tourniquet. A 5-cm longitudinal incision is made over the anterolateral leg approximately at the junction of the middle third and the distal third to encompass the two points.

A significantly more distal point of tenderness suggests a more distal piercing of the intermediate dorsal cutaneous nerve through the fascia, in which case two separate incisions may be made. Blunt subcutaneous dissection is done, and the nerve is found emerging through the fascia. A local fasciotomy is performed, releasing the nerve proximally and distally until it is completely free. In the setting of chronic compartment syndrome, a complete fasciotomy may be considered; however, the ensuing peroneal muscle weakness may affect athletic performance.

In cases of painful neuromas or clearly abnormal nerves due to direct or indirect trauma to the nerve, surgical excision of the nerve can be performed at the site of neuroma. If several branches are involved, excision of the nerve at the anterolateral leg can be considered. Dellon and Aszmann reported excellent results in nine of 11 patients who underwent resection of the nerve and translocation of the proximal nerve stump into the muscles of the anterolateral compartment, combined with fasciotomy of the anterolateral compartment. [67]

In cases of superficial peroneal nerve entrapment associated with other conditions, such as ankle instability, treatment of the associated conditions should also be planned.

Deep peroneal nerve entrapment

Once symptoms of deep peroneal nerve entrapment are deemed refractory to nonoperative measures, surgical options may be considered. Such options include the following:

  • Surgical release of the deep peroneal nerve in primary and idiopathic cases
  • Excision of the nerve in cases of direct nerve injury due to previous surgery, in cases of direct trauma, or in revision cases

Surgical decompression of the nerve can provide immediate improvement of symptoms.

Dellon reported on surgical release of the deep peroneal nerve in 20 patients. [68] At a mean follow-up of more than 2 years, excellent results were reported in 60% of patients, good results in 20% of patients, and no improvement in 20% of patients.

The surgical procedure can include part or all of a longitudinal straight or S-shaped incision on the dorsum of the foot, starting between the bases of the first and second metatarsals and extending proximally to the anterior ankle, depending on the predicted location of entrapment.

The deep fascia overlying the deep peroneal nerve and the dorsalis pedis artery is released, as is the inferior part of the extensor retinaculum; the superior part can be preserved to maintain the function of the extensor tendons. The deep peroneal nerve is followed proximally and distally to verify a full release. Nerves that appear to be normal in consistency and size can be released. [69]

It is important to treat other underlying causes of entrapment or stretch (eg, complete excision of underlying osteophytes during surgery). The decision to perform neurolysis as opposed to excision, transposition, or both is dependent on the severity of injury to the nerve.

Excision of the nerve is indicated in cases where the nerve is abnormal, as when it is directly manipulated during surgery or entrapped in scar tissue. Neuroma in continuity is best excised and allowed to retract into deep tissues, and transposition of the stump into muscle belly may be possible, depending on the level of excision. In a report describing excision of the superficial and deep peroneal nerves in the lateral leg, with translocation of the nerves into a muscle, Dellon and Aszmann obtained excellent results in nine of 11 patients. [67]

When entrapment of the deep peroneal nerve is caused by the extensor hallucis brevis, the muscle is hypertrophied and has thick fibrous bands that compress the nerve. Decompression of the nerve and excision of the muscle and fibrous band can lead to complete resolution of pain, but numbness may persist in the first webspace.

Interdigital neuritis

Surgical excision of the interdigital nerve and release of the intermetatarsal ligament with a dorsal or plantar approach results in a high percentage of successful results. The dorsal approach is recommended because of fewer potential complications and because it allows early weight bearing. Patients should be counseled preoperatively that varying degrees of postoperative numbness are commonly associated with resection of a Morton neuroma. Other surgical options include isolated intermetatarsal ligament release.

Most surgeons in the United States perform a primary surgical procedure via a dorsal approach. An incision approximately 3 cm long is centered in the relevant interspace, starting from the metatarsal head level and extending distally into the webspace. Blunt dissection into the webspace and placement of a lamina-style spreader reveals the intermetatarsal ligament. The proximal and distal aspects of the ligament are identified and released sharply.

An enlarged nerve may be identified readily beyond the ligament. Smaller nerves are more difficult to identify. In most cases, intertwining vessels require careful dissection and protection. The digital branches are identified and are sharply amputated distally. The nerve is then followed proximally, gently pulled distally, sharply amputated as far proximally as is visible, and allowed to retract into the deep soft tissues.

Mann and Reynolds reported retrospectively on a surgical excision of 76 Morton neuromas. [50] Although 65% of patients still noted some local plantar tenderness to touch, 80% showed subjective improvement. Coughlin and Pinsonneault noted residual pain in either the involved interspace or the adjacent one, which is not uncommon. [70] They also reported 85% good-to-excellent results and noted mild or major footwear restrictions in 70% of patients.

Dereymaeker et al reported on 32 feet treated with excision of a Morton neuroma via a dorsal incision. [71] Of the 32, 25 had a macroscopically visible neuroma, and two had no evidence of a neuroma on histologic examination. After resection, 81% had a good or excellent result, and 6.5% had no improvement. After the operation, 60% of the patients benefited from the long-term use of adapted shoes or inner soles. At the final follow-up, only 30% of the patients were found to be unrestricted in their choice of shoes.

The plantar approach to primary resection of an intermetatarsal neuroma, advocated by some, provides more direct access to the nerve and is technically simpler; however, painful plantar scars, intractable plantar keratosis beneath an adjacent lesser metatarsal head, and wound drainage have been reported. Consequently, most surgeons reserve this approach for revision cases. In a study of 57 plantar procedures done via a plantar incision, 23% of subjects had indurated plantar keratosis after surgery, and only 7% had poor results. [63]

Potential complications of interdigital nerve excision, including development of a stump neuroma and digital numbness, have led some authors to recommend release of the transverse metatarsal ligament with or without epineurolysis. Gauthier, reporting on the release of 304 intermetatarsal ligaments with epineural neurolysis, stated that 83% of patients had rapid and stable improvement and that 15% showed improvement but nonetheless experienced some persistent pain. [72]

Others, such as Weinfeld and Myerson, have advocated this procedure without neurolysis and have reported good preliminary results. [73] Mann and Reynolds cautioned against the use of this procedure except in the case of interdigital neuritis, noting reconstitution of the ligament in revision cases. [50]

Adjacent neuromas in the second and third interspace are not uncommon and should be investigated. Published reports of double neuromas are sparse. Benedetti et al reported simultaneous excision of two primary Morton neuromas in adjacent webspaces and noted significant pain relief in 84% of patients, but substantial numbness involving the third toe resulted. [74] Thompson and Deland described 89 adjacent neurectomies and reported results similar to those achieved with single neurectomies. [75]

Hort and DeOrio described 23 patients with adjacent intermetatarsal nerve irritation who underwent excision of the more enlarged nerve in one space and release of the intermetatarsal ligament in the other space, [76] an approach that allowed preservation of protective sensation. They reported 95% complete satisfaction, with no or only minimal activity limitation. Approximately 11% of patients had persistent pain with compression of the interspace where the nerve was released; none had pain in the interspace where the nerve was excised.

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