The Guidewire · Vol. III
Minimally Invasive Foot Surgery
The quiet
rise of
DMMO.
A burr. No fixation. Weight-bear on day one. How one extra-articular osteotomy quietly reshaped the conversation around metatarsalgia.
§ 01 — What this is
A percutaneous, extra-articular cut through the lesser metatarsal neck.
The Distal Metatarsal Minimally Invasive Osteotomy (DMMO) uses a Shannon-type burr through a sub-1 cm portal to transect the metatarsal at the metaphyseal-diaphyseal junction. No plate. No screw. No tourniquet required. The head is left to find its own position under the retrograde pull of tendons and immediate weight-bearing — a functional reduction, not a fixed one.
Think of it as the surgical equivalent of a well-controlled metatarsal neck fracture — one you created on purpose, in the right plane, at the right level.
§ 02 — Why it matters
The Weil osteotomy has real problems. DMMO targets each one.
The Weil has been the workhorse for propulsive metatarsalgia for three decades. It also has a well-documented reputation for joint stiffness, floating toe, and transfer metatarsalgia. DMMO was developed specifically to keep the corrective mechanics of shortening and elevation while abandoning the intra-articular exposure, the hardware, and the soft-tissue dissection that seem to drive those complications.
§ 03 — The framework
How the cut behaves.
01
Portal & approach
Stab incision dorsolateral to the MTPJ. Burr introduced to the metaphyseal-diaphyseal junction of the lesser metatarsal, just proximal to the flare of the head.
02
The osteotomy
Cut oriented roughly 45° in the sagittal plane, from dorsal-distal to plantar-proximal. Extra-articular. Tangential. Two to three millimetres of bone are consumed by the burr kerf itself.
03
No fixation
Capsule, collateral ligaments, and plantar plate are left untouched. The fragment is free to translate in three dimensions.
04
Weight-bearing is the reduction
Immediate full weight-bearing in a flat postoperative shoe. Retrograde tendon pull and plantar pressure "mold" the head into shortening plus elevation. This is not an adjunct — it is the technique.
05
Almost never solo
Isolated single-ray DMMO invites transfer metatarsalgia. The literature consistently treats multiple adjacent rays to preserve the parabola.
§ 04 — The literature curve
A procedure that took its time becoming mainstream.
Fig. 01 · PubMed-indexed publications mentioning "DMMO"
Approximate counts, 2005–2025. Shows diffusion from European technique papers into systematic reviews, modifications, and expanding indications.
Source: synthesized from PubMed searches using "DMMO" and "distal metatarsal minimally invasive/metaphyseal osteotomy" as title/keyword terms, accessed April 2026. Counts are approximate — duplicate indexing, variant nomenclature (DMDO, DICMO, DOMMO, S-DMMO), and non-indexed European literature make precise counts unstable. Trend is the point; the numbers are not gospel.
§ 05 — The comparison that drives the decision
DMMO vs. Weil.
Axis
DMMO
Weil
Approach
Percutaneous, <1 cm portal
Open dorsal, longitudinal
Joint
Extra-articular
Intra-articular
Fixation
None
Screw (typically)
Correction
Dynamic — set by weight-bearing
Static — set by surgeon
Weight-bearing
Immediate, essential
Protected, variable protocols
Floating toe
Lower reported rates
Well-described complication
MTPJ stiffness
Lower risk (extra-articular)
Higher risk
Edema
Longer, months-long swelling
Shorter, more predictable
Radiographic union
Slower; delayed union ~11% pooled
Faster, more predictable
§ 06 — Key concepts & variants
The family keeps growing.
DMMO (classic)
45° metaphyseal-diaphyseal cut on a lesser metatarsal. No fixation.
Oblique DMMO
Steeper cut angle to favor shortening over elevation, tuned to the metatarsal parabola.
Reverse DMMO
Plantar-distal to dorsal-proximal orientation — used when elevation is the dominant deformity.
DICMO
Distal intracapsular minimally invasive osteotomy — a newer modification keeping the cut closer to the head.
DOMMO
Distal oblique minimally invasive osteotomy — Redfern/Vernois-associated technique widely cited in UK/European literature.
S-DMMO
Sliding DMMO of the fifth metatarsal — applied to bunionette correction.
DMMO + DTML release
Emerging approach to Morton's neuroma: percutaneous release of the deep transverse intermetatarsal ligament combined with a 4th-ray DMMO.
Shannon burr
The small-diameter, long-fluted cutting burr that defines the instrument footprint. Kerf width contributes 2–3 mm of automatic shortening.
§ 07 — Decision lens
How surgeons actually think about picking it.
Patient factor
Soft-tissue quality. Diabetics, vasculopaths, smokers, thin-skinned elderly — DMMO's closed approach is attractive wherever open incisions worry you.
Deformity shape
Global parabola problem vs. isolated ray. DMMO shines when multiple rays need reshaping. A truly isolated lesion may be better served by a precise fixed osteotomy.
Compliance
Will this patient actually walk? The molding depends on immediate, sustained weight-bearing. A non-ambulatory patient or one who refuses to bear weight is the wrong candidate — full stop.
Surgeon experience
The learning curve is real. Burr handling, portal placement, and avoiding intra-articular propagation all take reps. Cadaver training before live surgery is the consensus position.
Tolerance for swelling
The trade you are selling. A patient who cannot tolerate three to six months of forefoot edema is the wrong patient, regardless of how elegant the approach looks on imaging.
§ 08 — Pitfalls & pearls
What goes wrong. What gets memorized.
Pitfalls
- Operating on a single metatarsal and creating transfer metatarsalgia next door.
- Allowing the cut to propagate intra-articularly — particularly with the standard approach.
- Offering DMMO to a patient who will not or cannot weight-bear.
- Underselling the swelling timeline — 3 to 6 months is routine.
- Ignoring delayed union (~11% pooled) when interpreting the 8-week film.
- Expecting open-surgery precision from a dynamic osteotomy.
Pearls
- The burr kerf is part of the correction. Don't resect more than the plan.
- Treat the parabola, not a single ray.
- Extra-articular placement is the whole point — stay proximal to the flare.
- Counsel swelling up front. Photograph both feet preop.
- Delayed union ≠ nonunion. Clinical painless weight-bearing trumps the film.
- Train on cadaver before patient. Every MIS thought leader says this.
§ 09 — Controversies & current trends
Where the experts still disagree.
Evidence tier
Level IV dominates. Systematic reviews exist; randomized comparative trials against Weil are scarce. Enthusiasm outpaces high-tier evidence.
Standard vs. intraosseous approach
Cadaveric data suggests the classic approach injures capsule and EDL more than a modified intraosseous route. Whether that translates clinically is open.
Expanding indications
Beyond metatarsalgia. Morton's neuroma (DMMO + DTML release), bunionette (5th-ray S-DMMO), brachymetatarsia lengthening, and even hallux rigidus via 1st-ray DMMO are all in active literature development.
Nomenclature chaos
DMMO, DMDO, DICMO, DOMMO, S-DMMO, Converse DMMO. The field is still sorting out which names denote truly distinct techniques and which are rebrands of the same cut.
Confidence · 7 / 10
Mechanics, indications, and complication spectrum are well-described. What remains soft: head-to-head RCT data against Weil, long-term functional durability beyond 5 years, and which of the many variants actually outperforms the original.
⚠ Verify locally before applying.
⚠ Verify locally before applying.
§ 10 — Sources
Selected reading.
- Laffenetre O, Lucas y Hernandez J, Cerrato R. Minimally Invasive Lesser Metatarsal Osteotomies and Their Variations. Foot Ankle Clin. 2025;30(3):489–506.
- Henry J, Besse JL, Fessy MH, Colin F. Distal Metatarsal Minimally Invasive Osteotomy (DMMO): Surgical technique, variants, indications, and treatment decision-tree. Orthop Traumatol Surg Res. 2021.
- De Prado M, Cuervas-Mons M, Golanó P, Vaquero J. Distal metatarsal minimal invasive osteotomy (DMMO) for the treatment of metatarsalgia. Tech Foot Ankle Surg. 2016;15(1):12–18.
- Haque S, Kakwani R, Chadwick C, et al. Outcome of Minimally Invasive Distal Metatarsal Metaphyseal Osteotomy (DMMO) for Lesser Toe Metatarsalgia. Foot Ankle Int. 2016;37(1):58–63.
- Redfern DJ, Vernois J. Percutaneous surgery for metatarsalgia and the lesser toes. Foot Ankle Clin. 2016;21(3):527–550.
- Sato G, Ferreira GF, Sevilla D, et al. Treatment of Morton's neuroma with DMMO and percutaneous DTML release. Int Orthop. 2022;46(12):2829–2835.
- Complications in DMMO: Systematic Review and Meta-Analysis. Medicina (Kaunas). 2025. PRISMA-registered, CRD420251067666.
Disclaimer. This document was produced with the assistance of AI tools under author supervision and is educational in nature. It is not a surgical technique guide, a billing reference, or a substitute for mentored training, IRB-governed research, or independent clinical judgment. All surgical decisions belong to the treating surgeon and their patient.