Midfoot Arthritis

Midfoot arthritis affects the tarsometatarsal (Lisfranc) joints and/or naviculocuneiform joints and is an important cause of midfoot pain and disability.

Epidemiology: Symptomatic midfoot OA affects about 12% of adults over 50 (Thomas/Roddy 2015) and is mechanically driven (obesity, prior injury, female sex, age over 75). Post-traumatic disease dominates in younger active patients - radiographic OA develops in roughly 70% and symptomatic OA in about half after surgically treated Lisfranc injuries (Dubois-Ferriere 2016).

Anatomy

The midfoot is divided into three columns:

• Medial column: 1st metatarsal, medial cuneiform
• Middle column: 2nd and 3rd metatarsals, intermediate and lateral cuneiforms - this is the "keystone" providing stability
• Lateral column: 4th and 5th metatarsals, cuboid

Pathophysiology

The medial and middle columns are intrinsically rigid (the 2nd TMT is recessed in a mortise between the cuneiforms - the "keystone"), with very little physiological motion; the lateral column is comparatively mobile to allow the foot to accommodate uneven ground. Cartilage loss and incongruity at these load-bearing joints generate dorsal shear and osteophyte (dorsal boss) formation, which impinges on shoe wear and at push-off. Because the medial/middle columns normally move little, fusing them sacrifices minimal function - the biomechanical rationale for arthrodesis being well tolerated there while lateral column motion is protected.

Etiology

Primary Osteoarthritis: Most common. Idiopathic degeneration.

Post-Traumatic: Following Lisfranc injury (even subtle ligamentous injury can lead to arthritis).

Inflammatory Arthritis: RA, psoriatic arthritis, gout (particularly 1st TMT).

Neuropathic (Charcot): Diabetic neuroarthropathy can affect midfoot.

History

Dorsal midfoot pain worse with walking, running, or standing. Pain with push-off phase of gait. Difficulty wearing shoes (dorsal osteophytes rub). May report prominence on top of foot. Worse on uneven ground.

Examination

Inspection: Dorsal prominences (osteophytes) may be visible. Swelling over midfoot.

Palpation: Tenderness over affected TMT joints. Palpable dorsal spurs.

Range of Motion: Pain with midfoot pronation/supination. Reduced naviculocuneiform motion if involved.

Gait: May have antalgic gait or limited push-off.

Weight-Bearing Radiographs: Essential for assessment.

AP Foot: Shows TMT joint space narrowing, osteophytes, any malalignment.

Lateral Foot: Shows dorsal osteophytes, any collapse.

Oblique View: Best visualization of TMT joints.

CT Scan: Details joint involvement for surgical planning. Shows extent of arthritis.

MRI: For soft tissue assessment or early disease. Shows bone marrow edema.

Findings

Classic features include joint space narrowing, subchondral sclerosis, dorsal osteophytes, and subchondral cysts. Dorsal osteophyte impingement is a common source of symptoms.

Differential Diagnosis

Dorsal midfoot pain is not specific. The key examiner skill is distinguishing localised TMT/NC arthritis from mimics that change management entirely (especially Charcot and stress fracture, where surgical fusion or weight-bearing through an arthritic joint can be catastrophic).

The central surgical principle of this topic is "fuse ONLY the symptomatic joints", and it repeatedly notes the intra-articular injection is "diagnostic and therapeutic" and that "injection response predicts surgical outcome" - but it never explains how to USE injections to localise the true pain generator, which is the step that operationalises selective fusion.

• Why it is needed. Dorsal midfoot pain is diffuse and poorly localised, and radiographic OA is frequently multi-joint yet not uniformly symptomatic (radiographs over-call the pain source - Dubois-Ferriere showed radiographic OA outstrips symptoms). Fusing every arthritic-looking joint over-treats, stiffens more of the foot, and raises non-union risk (which climbs with the number of joints fused).
• The technique. Perform an image-guided (fluoroscopic or ultrasound) selective single-joint local-anaesthetic injection into each suspected joint, ideally on separate occasions. A positive test - transient near-complete abolition of the patient's typical pain - confirms that joint as a pain generator and includes it in the fusion; a joint whose injection does not relieve pain can be spared. A small dose of corticosteroid added gives concurrent therapeutic benefit.
• Prognostic value. A good (if temporary) response to the diagnostic block predicts a good response to arthrodesis of that joint - so a poor or absent response should prompt reconsideration of the diagnosis (Charcot, stress fracture, referred pain) before committing to fusion.
• The pitfall. Contrast/anaesthetic leak between communicating joints can give a false positive; injecting the smallest effective volume under image guidance and correlating with the patient's pain map limits this.

The topic states that fusion should be done with "slight plantarflexion of the first ray to maintain arch height" and warns that "dorsal malposition of the first ray alters load and gait", but never explains the beam mechanics behind this - the difference between a well-positioned and a malpositioned fusion.

• The medial column as a beam. The medial column (talus - navicular - medial cuneiform - first metatarsal) acts as a rigid beam/lever that must be held in slight plantarflexion so the first ray reaches the ground and shares load at push-off; the plantar structures (plantar fascia, spring ligament, tibialis posterior and peroneus longus) tension this beam.
• Why position is everything at fusion. Arthrodesis fixes the alignment permanently, so the joint must be set at the correct height and rotation:
  • Dorsal malunion (first ray left too dorsiflexed / elevated) shortens and elevates the medial column, flattening the arch and transferring load laterally and to the lesser metatarsal heads - producing transfer metatarsalgia, lateral overload and lesser-ray stress fractures (the second-metatarsal stress fractures Mann reported).
  • Excessive plantarflexion overloads the first metatarsal head (sesamoid pain, intractable plantar keratosis).
  • Malrotation or residual forefoot abduction leaves a splayed, hard-to-shoe foot.
• How it is set. Reduce the first ray to slight plantarflexion with the forefoot plantigrade, confirm the first and second metatarsal bases realign (restoring the normal first-second TMT relationship) and that medial arch height matches the contralateral side on the weight-bearing lateral, before definitive fixation. (The radiographic tool for quantifying medial-column sag, Meary's angle, is developed in the meary-angle topic.)

Complications relate chiefly to arthrodesis; untreated arthritis itself causes progressive pain, deformity and disability.

• Non-union: 5-10% for medial/middle column constructs, rising with the number of joints fused and in smokers, diabetics, inflammatory arthropathy and the lateral column (Dang et al 2020). Mann et al (1996) achieved 98% union in a largely medial/middle-column series.
• Malunion / residual deformity: Loss of arch height or dorsal malposition of the first ray alters load and gait; slight plantarflexion of the first ray at fusion guards against this.
• Adjacent / transfer overload: Stiffening the midfoot transfers stress to neighbouring joints; inappropriate lateral column fusion causes lateral foot pain and metatarsal stress fracture (3 cases in Mann et al 1996).
• Wound and soft-tissue problems: Dorsal incisions risk skin slough and incisional neuroma (superficial peroneal/deep peroneal branches); higher risk in diabetics, smokers and inflammatory disease.
• Hardware prominence / failure: Dorsal plates and screws may be palpable and require removal; hardware can fail before union.
• Infection: Increased in diabetics, smokers and patients on biologics - a key reason for perioperative medication planning.

Global Epidemiology

Symptomatic midfoot OA affects about 12% of community-dwelling adults aged 50 and over (UK Clinical Assessment Study of the Foot; Thomas, Roddy et al 2015), making it more common than often assumed. It is more frequent in women, those over 75, and people with obesity, prior foot/ankle injury or pain in other weight-bearing joints - a mechanically driven pattern. Post-traumatic disease is the dominant cause in younger active patients: radiographic OA develops in roughly 70% and symptomatic OA in about half after surgically treated Lisfranc injuries at long-term follow-up (Dubois-Ferriere et al 2016).

Guideline Comparison

There is no single dedicated international midfoot-arthritis surgical guideline; practice is principle-based and draws on adjacent society guidance.

The consistent global thread: exhaust conservative care first; fuse only the symptomatic joints; preserve an uninvolved lateral column.

Registry Notes

Unlike arthroplasty, midfoot arthrodesis is not systematically captured by national joint registries (NJR, AJRR, AOANJRR, SHAR all focus on implant replacement), so robust population-level outcome data are lacking. Evidence rests on institutional case series, which is itself a driver of the uncertainties above.

High- versus Limited-Resource Practice

In well-resourced settings, custom carbon-fibre orthoses, image-guided injections, CT planning and locking-plate fixation are routine. In limited-resource settings, stiff-soled footwear, generic rigid insoles and screw-only fixation remain effective and cost-conscious alternatives, and weight-bearing radiographs (rather than CT) carry most diagnostic decisions. The core principles of selective fusion and lateral column preservation apply universally.

Midfoot arthritis surgery is governed more by principle than by high-level evidence; several areas remain genuinely debated and are favourite examiner territory.

• Primary arthrodesis versus ORIF for ligamentous Lisfranc injuries. Ly & Coetzee's RCT (JBJS Am 2006) favours primary fusion for purely ligamentous patterns, but the trial is small (n=41), single-centre, and does not settle the question for bony or combined injuries, where ORIF (or flexible/suture-button fixation) remains common. The relevance to established arthritis is indirect.
• How many joints to fuse. Fusing only symptomatic joints preserves function and lowers non-union risk (Dang et al 2020), but under-fusion risks persistent pain from joints that later decompensate. There is no validated threshold for including the naviculocuneiform or intercuneiform joints, and the decision is often made intraoperatively.
• Lateral column - fuse or preserve. The lateral (4th-5th TMT) column should usually be preserved for gait adaptation, yet in inflammatory or severely arthritic disease it may need fusion. Some advocate interposition arthroplasty/resection rather than rigid fusion of the lateral column to retain some motion - evidence is limited.
• Role of cheilectomy / dorsal exostectomy alone. Isolated removal of a dorsal boss can relieve shoe-related impingement but does not address the underlying arthritis; durability is uncertain and many regard it as temporising.
• Fixation technology. Dorsal locked compression plates have not improved fusion rates over conventional screws/plates (Dang et al 2020); the optimal construct (screws vs plate vs combined, lag vs neutralisation) is unsettled.
• Perioperative biologic management. The ACR/AAHKS guidance (Goodman et al 2017) is extrapolated from arthroplasty, conditional, and based on low-to-moderate quality evidence; the ideal timing of TNF-inhibitor withdrawal around foot/ankle fusion is not directly studied.

Midfoot arthritis primarily affects the tarsometatarsal (Lisfranc) joints and naviculocuneiform joints, most commonly caused by primary osteoarthritis or post-traumatic degeneration following Lisfranc injuries. The medial column (1st TMT) is most commonly symptomatic, presenting with dorsal midfoot pain worse with activity and palpable dorsal osteophytes. First-line treatment involves stiff-soled shoes and orthotics; definitive management for refractory cases is midfoot fusion. The lateral column (4th/5th TMT) motion should be preserved when possible as it is important for gait adaptation on uneven terrain.