How to manage Morton’s Neuroma complications
Marino Delmi, M.D.
Foot & Ankle Centre – Clinique des Grangettes - Geneva, Switzerland
What is the problem?
Morton’s nevroma surgery seems very “simple” but is actually very difficult with many complications, bad results and “recurrences”.
|
% |
Good |
Bad |
Re-do |
Numbness |
Normal shoes |
|
Bennett,1996 |
85 |
15 |
21 |
|
|
|
Dereymaeker 1996 |
81 |
19 |
|
|
30 |
|
Jarde, 1995 |
89 |
11 |
|
41 |
75 |
|
Assmus,1994 |
81.5 |
18.5 |
|
11.1 |
|
|
Ruuskanen 1994 |
80 |
20 |
9 |
|
|
|
Keh, 1992 |
93 |
7 |
|
|
|
Differential diagnosis of recurrent pain : What are the reasons for these “bad” results?
1. Differential diagnosis is wide and may lead to wrong treatment: synovitis, bursitis, MTP arthritis, Freiberg’s infarction, stress fracture, wart, mechanical hyperpressure, hyperlaxity of a MTP joint, tarsal tunnel syndrome, etc. In this situation, the so-call “recurrence” of pain is simply the consequence of the false treatment and the persistence of the etiologic problem.
Treatment: treat the cause of the pain !
2. Excision of the nerve is followed by the formation of a stump neuroma. This is a normal process, but if this plantar nevroma is too big or too distal, it will be very painful. Treatment : second excision, more proximal, using the primitive dorsal approach or a plantar incision. In case of persistent problem due to a painful recurring nevroma, a redo with a tubular venous autograft could be the salvage solution (see “Surgical procedure”).
3. Loss of sensation due to removal of the nerve is also normal, but may be the cause of bothering dysesthesia.
Treatment : no surgery, but conservative measures including pain killer, gabapentine, clonazepam, TENS, “trigger points” desensitization, specific insoles, etc.
4. The scar itself, if plantar, is sometimes source of painful intractable plantar keratosis. Treatment : avoid plantar incision! Specific relief insoles. Surgery: excise the scar – plastic surgery.
Surgical procedure : Venous tubular autograft of the proximal stump of the interdigital nerve.
Litterature
1. Bennett GL, Graham CE, Mauldin DM : Morton's interdigital neuroma: A comprehensive treatment protocol. Foot Ankle Int 1995; 16: 760-3.
2. Dereymaeker G, Schroven I, Steenwercks A, Stuer P. : Results of the excision of the interdigital nerve in the treatment of the Morton's metatarsalgia. Acta Orthop Belg 1996; 62: 22-5.
3. Schon LC, Lam
PW, Easley ME, Anderson CD, Lumsden DB, Shanker J, Levin GB. Complex
salvage procedures for severe lower extremity nerve pain. Clin Orthop Relat
Res. 2001 Oct;(391):171-80.
