Chapter 51 PERINEURAL FAT GRAFTING FOR THE MANAGEMENT OF NEUROMAS AND PAIN SYNDROME
10.1055/b-0038-149587
Chapter 51 PERINEURAL FAT GRAFTING FOR THE MANAGEMENT OF NEUROMAS AND PAIN SYNDROME
Luca Vaienti, Riccardo Gazzola
The management of painful neuromas and pain syndrome is a challenging clinical problem. A neuroma is the natural nerve reaction to damage and can be symptomatic in 3% to 5% of cases.1The pain caused by a neuroma is often intense and continuous and, in some cases, can be elicited by a light stimulus on the overlying skin, making even daily manual activities impossible. Uncommonly, pain can arise spontaneously and interfere with sleep. Presentation to the surgeon typically does not occur until the pain is unbearable and after pharmacologic therapies have already been attempted but have been unsuccessful. Moreover, this late presentation to the surgeon usually increases the odds of a centralization of pain, making it difficult for any surgery on the peripheral nervous system to succeed.
A multitude of treatments for neuromas have been described in the literature over the years, but none of these treatments was very effective. All surgical techniques have the common aim of preserving the nerve from microtrauma and scar adherence, avoiding continuous stress and pain. In a neuroma in continuity after the neuroma is excised, the continuity is restored with a nerve graft. Otherwise, the proximal nerve stump is usually transposed into an intact site, usually a muscle or vein.
The introduction of structural fat grafting by Coleman2brought a new regenerative substrate to plastic and hand surgery. In fact, the adipose fat graft processed according to his technique can provide effective protection against external stresses, lower perineural adherences, and create an environment that favors nerve regeneration. There are several potential applications of this substrate in pain syndromes without any limitation concerning the site of the pain. In 2010, I (L.V.) first applied autologous fat grafting to the treatment of terminal neuromas of the upper limb.3The same technique was then applied in larger series and is now a valid alternative for the treatment of neuropathic pain, extending its indication from terminal painful neuromas to neuromas in continuity and neuropathies.
CAUSES OF PAINFUL NEUROMAS
A neuroma occurs as the result of nerve injury. In particular, it is the regenerative reaction of the damaged axons to the injury. The key phenomenon that better describes this occurrence is the fascicular escape, when the intact perineurium acts as an impenetrable barrier to regenerating axons. When the perineurium is damaged, the axonal regeneration occurs externally to this sheath. Schwann cells, fibroblasts, and neoangiogenesis also support this phenomenon.4Although Schwann cells can be found in the neuroma, the axons are usually demyelinated, small, and without any polarized growth.
Table 51-1 Neuropathic Pain
Stimulus
Mechanism
Clinical Description of Pain
Diagnosis
Chronic irritation
Mechanical or chemical stimuli to the axons
Poor myelination of nerve fibers increases sensibility
Spontaneous, hyperesthesia, pain evoked by pressure, and pain evoked by joint flexion†
Clinical examination, Tinel test, selective blocks, ultrasonography MRI can be considered for deep neuromas
Central pain
Not required
Spontaneous activity of the neurons of the radicular ganglion, dorsal horn, and more proximal levels*
*Birch R. Nerve repair. In Wolfe SW, Pederson WC, Hothkiss RN, et al, eds. Green’s Operative Hand Surgery, ed 6. Philadelphia: Churchill Livingstone, 2010.
†Sood MK, Elliot D. Treatment of painful neuromas of the hand and wrist by relocation into the pronator quadratus muscle. J Hand Surg Br 23:214, 1998.
COMMON NEUROMAS AND SURGICAL OPTIONS
A painful neuroma can be the result of trauma, chronic microtraumas (such as bowler’s thumb, a lesion provoked by microtrauma to the collateral ulnar nerve of the thumb when it is inserted into the bowling ball5), iatrogenic damage, or amputations (10% to 15% of stumps develop chronic neuropathic pain6).
Common sites of neuromas are the superficial branch of the radial nerve, the cutaneous antebrachial nerves, the median nerve (usually an iatrogenic occurrence after carpal tunnel release), and the palmar cutaneous nerves (where a neuroma may develop as a result of a sharp trauma).
Table 51-2 Surgical Options
Surgery
Indications
Aims
Pros and Cons
Neuroma resection plus direct neurorrhaphy
Available distal nerve stump
Adequate soft tissue coverage
Primary neuroma
The nerve gap can be closed primarily with a direct neurorrhaphy
Remove pain
Restore sensitivity
PROS: Effective in restoring sensitivity and removing pain
CONS: Limited indications
Neuroma resection plus nerve graft
Available distal nerve stump
Adequate soft tissue coverage
Primary neuroma
The nerve gap is wider and cannot be closed primarily
Remove pain
Restore sensitivity
PROS: Effective in restoring sensitivity and removing pain
CONS: Limited indications
Longer procedure
Requires a nerve graft and consequent anesthesia of the donor nerve
Neuroma resection
Distal nerve stump is not available
Inadequate tissue coverage and wide scar adherences
Secondary neuroma or multiple relapses
Remove pain
PROS: Simple procedure
CONS: High rate of relapse
Greater chance of success can be achieved by resecting a nerve segment of 10 cm*
Inadequate tissue coverage and wide scar adherences
Secondary neuroma or multiple relapses
Remove pain
PROS: Inhibits axonal growth and fascicular escape
More effective than simple neuroma resection
Protects against stimuli (when silicone caps or nerve tubes are used)
CONS: Frequent relapses
Neuroma resection plus transposition (bones, muscles, veins)
Distal nerve stump is not available
Inadequate tissue coverage and wide scar adherences
Secondary neuroma or multiple relapses
Remove pain
PROS: Stump is positioned in healthy tissue
Protects against traumatisms
Venous endothelium increases myelinization of nerve fibers§
CONS: Stability of relocation
Fixation of the stump could theoretically damage the nerve during movement, producing a new neuroma
Muscle relocation cannot be applied in superficial muscles or muscles with wide excursion¶
*Birch R, Bonney G, Wynn Parry CB. Resection of terminal neuromas. In Birch R, Bonney G, Wynn Parry CB, eds. Surgical Disorders of the Peripheral Nerves. London: Churchill Livingstone, 1998.
†Tupper JW, Booth DM. Treatment of painful neuromas of sensory nerves in the hand: a comparison of traditional and newer methods. J Hand Surg Am 1:144, 1976.
‡Dahlin LB, Lundborg G. Use of tubes in peripheral nerve repair. Neurosurg Clin N Am 12:341, 2001.
§Koch H, Herbert TJ, Kleinert R, et al. Influence of nerve stump transplantation into a vein on neuroma formation. Ann Plast Surg 50:354, 2003.
¶Laborde KJ, Kalisman M, Tsai TM. Results of surgical treatment of painful neuromas of the hand. J Hand Surg Am 7:190, 1982.
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May 22, 2020 | Posted by drzezo in General Surgery | Comments Off on Chapter 51 PERINEURAL FAT GRAFTING FOR THE MANAGEMENT OF NEUROMAS AND PAIN SYNDROME