Hallux Varus

Hallux varus is medial deviation of the great toe at the first metatarsophalangeal (MTP) joint, the hallux angulated medially relative to the long axis of the first metatarsal by more than 10 degrees. [1] The normal hallux sits in 5-15 degrees of valgus. [2]

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Who gets it. Iatrogenic hallux varus follows approximately 5-15% of hallux valgus corrections, which makes it the most common cause in adults [3]; other series put it at roughly 2-13%, the figure varying with technique and definition. Congenital hallux varus is rare, often associated with metatarsus adductus or part of a polydactyly syndrome [4], and traumatic hallux varus follows crush injuries, burns or medial soft-tissue trauma with subsequent contracture. Iatrogenic cases mirror the demographics of bunion surgery and are predominantly female; congenital cases are equally distributed between the sexes.

Why it matters. The first MTP joint normally bears 40-60% of forefoot weight during terminal stance, and the hallux is the principal contributor to propulsion at that point. A varus hallux contributes less and shifts load laterally onto the lesser metatarsals. [5] The consequences:

• Reduced push-off power and gait inefficiency
• Transfer metatarsalgia, with pain and calluses under the second and third metatarsal heads [17]
• Gait instability, because loss of medial tripod support reduces balance
• Difficulty with shoes, as the varus toe crowds the second toe and creates abnormal pressure points, and the deformity is cosmetically distressing

History. Hallux varus was first described in relation to overcorrection after bunion surgery in the mid-20th century. Early bunion operations often combined aggressive medial eminence resection and medial capsulorrhaphy without balancing the lateral structures, and produced high rates of iatrogenic varus. Modern bunion surgery emphasises preservation of sesamoid balance and judicious soft-tissue release. [6]

Hallux varus falls into three main categories by aetiology: iatrogenic, congenital and traumatic.

Iatrogenic

The most frequent cause in adults is overcorrection during hallux valgus surgery [7], and its flexibility varies from case to case. The technical errors that produce it:

• Excessive medial eminence resection. Removing too much medial bone eliminates the medial buttress, and the unopposed pull of abductor hallucis and extensor hallucis longus (EHL) draws the toe medially. The risk increases if resection extends beyond the sagittal sulcus of the metatarsal head.
• Overtightening of the medial capsule. Aggressive capsulorrhaphy or plication creates excessive medial tension, and with inadequate lateral release the soft-tissue forces are unbalanced. It was common in older McBride-type procedures.
• Fibular sesamoidectomy. The fibular sesamoid acts as a lateral buttress, and removing it allows medial deviation. The risk is higher when it is combined with other medial-sided procedures.
• Disruption of the lateral structures. Injury to the lateral capsule, lateral collateral ligament or adductor hallucis during exposure, or an overzealous lateral release in an attempt to correct a severe bunion.
• Overcorrection with osteotomy. Excessive varus angulation through a distal metatarsal osteotomy (chevron, scarf), or malunion in varus after a proximal osteotomy.

Congenital

Congenital hallux varus is rare and typically presents in infancy or early childhood. [8] It is present at birth, and the causes include:

• Metatarsus adductus: the first metatarsal is deviated medially, creating a relative hallux varus
• Delta (trapezoid) phalanx: an abnormal wedge-shaped proximal phalanx drives progressive varus angulation
• Polydactyly remnants: incomplete resection, or scarring after excision of a polydactyly
• Congenital contracture of a tight abductor hallucis or the medial capsular structures

Most congenital cases are flexible and may improve with growth, and asymptomatic ones are observed. Rigid cases, and those with a structural bone abnormality, require surgical correction, with soft-tissue release for the rigid toe.

What else to look for. In the congenital case report illustrated below (Manni), plantar inspection also showed associated cavus, inversion and lesser-toe clawing, which must be included in reconstruction planning. Radiographs localised a severe bilateral deformity to the first MTP joints and showed shortened first metatarsals, measurements that influence the need for osteotomy.

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Traumatic

Post-traumatic hallux varus comes with a history of trauma and with scarring, and skin quality may be a problem. Treatment releases the contractures, addresses the scarring and reconstructs as needed. The mechanisms:

• Soft-tissue contracture: burns, crush injuries or lacerations causing medial scar contracture
• Disruption of the lateral stabilisers: rupture of the lateral collateral ligament or the adductor hallucis tendon
• Malunion: fractures of the first metatarsal or proximal phalanx healing in varus
• Loss of the fibular sesamoid: traumatic excision or loss in a severe injury

The balance. The hallux is held in physiological valgus by opposing forces across the MTP joint:

• Medial, varus-producing: abductor hallucis (inserting on the medial base of the proximal phalanx), the EHL once the toe is in varus, and the medial capsule and collateral ligament
• Lateral, valgus-producing: adductor hallucis (inserting on the lateral base and the fibular sesamoid), flexor hallucis brevis through both sesamoids, the lateral capsule and collateral ligament, and the fibular sesamoid acting as a lateral buttress

Flexible deformity. The medial forces overpower the lateral ones, but the joint remains mobile and passively correctable. The EHL, which normally runs in a straight line, now bowstrings medially and becomes a dynamic deforming force. [9]

Rigid deformity. Chronic imbalance leads to capsular contracture and fibrosis, adaptive shortening of the medial structures and eventually joint stiffness or arthrosis. The deformity becomes fixed and cannot be corrected passively.

History. Patients complain of the look of the toe, of shoes (the toe rubs on the adjacent toe or the medial side of the shoe), of pain at the MTP joint, especially if it is arthritic, of transfer metatarsalgia, and of difficulty with push-off and sport. The answers that shape management:

• Duration (congenital or acquired), whether it is progressive or stable, and the inciting event: surgery, trauma or insidious onset
• Treatments already tried
• Prior bunion surgery (timing, procedure type, complications), revisions and other foot procedures
• Numbness or tingling, from nerve injury at previous surgery
• Stiffness, which suggests a rigid deformity

Inspection and palpation. Examine standing, measuring the varus angle of the hallux against the first metatarsal, and look at the whole forefoot:

• Skin: scars from surgery or trauma, calluses on the medial hallux or the lateral lesser toes
• Adjacent toes: crossover or crowding of the second toe
• Hindfoot: associated pes planus or cavus
• First MTP joint: tenderness, effusion, and crepitus suggesting arthritis
• Medial eminence: prominence, or deficiency after over-resection
• Sesamoids: plantar tenderness and position
• Lesser metatarsal heads: tenderness suggesting transfer metatarsalgia

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Movement. Normal first MTP motion is 70-80° of dorsiflexion and 20-30° of plantarflexion. Assess IP joint flexion and extension as well; pain or crepitus with motion indicates arthritis.

The passive correction test is the single most important clinical test, and it decides the operation. Grasp the hallux and push it laterally while stabilising the first metatarsal. If the toe readily corrects to neutral or beyond into valgus, the deformity is flexible and amenable to soft-tissue procedures such as EHL transfer; if it does not correct, it is rigid and arthrodesis is usually required. Two further tests identify what the reconstruction must address:

Neurovascular examination and gait. Check the dorsalis pedis and posterior tibial pulses, sensation in the deep peroneal, medial plantar and saphenous territories, and motor function of EHL, FHL and the intrinsics. In stance, look at weight distribution and any tendency to offload the hallux; at push-off, a diminished hallux contribution and lateral forefoot loading.

Medial deviation or a "crooked" great toe has several mimics. The key discriminators are the direction of deviation, the level of deformity, and the history.

Non-operative treatment does not correct the deformity but may reduce symptoms, and a flexible deformity may still progress to a rigid one despite it. Congenital hallux varus is often observed, and surgery is rarely needed. The indications:

• Asymptomatic or minimally symptomatic deformity
• Congenital cases in young children, who have a high rate of spontaneous improvement
• Medical comorbidities precluding surgery
• Patient preference

The options:

• Observation: many congenital cases improve with growth
• Shoe modification: a wide toe box, soft uppers and custom orthotics to accommodate the deformity
• Toe spacers: soft silicone spacers between the hallux and second toe provide a lateral corrective force, with limited efficacy
• Taping or dynamic splinting to hold the toe corrected, which may slow progression in flexible cases
• Activity modification, avoiding what aggravates it

The operative decision. Four questions, in order:

1. Is it flexible? Perform the passive correction test, under fluoroscopy if needed.
2. Is the joint arthritic? Review the radiographs; an arthritic joint narrows the surgical options to arthrodesis.
3. What is deforming it? Look for EHL bowstringing, abductor hallucis contracture, capsular contracture and bone deformity.
4. Select the procedure: EHL transfer with or without adjuncts for the flexible, non-arthritic toe; arthrodesis for the rigid or arthritic one; an added osteotomy for bone deformity.

Prognosis. Flexible deformity carries the better prognosis, and does well with appropriate soft-tissue surgery. Arthrodesis for the rigid toe is reliable, at the cost of motion.

EHL TransferArthrodesisReverse Akin

EHL Transfer (Johnson Procedure)

Principle. With the toe in varus, the EHL bowstrings medially and becomes a deforming force. Transferring it to the lateral side of the proximal phalanx removes the medial pull and creates a new lateral stabilising force. [12] What happens to the IP joint depends on whether the whole tendon or half of it is moved, which is set out in the next section.

Indications

• Flexible hallux varus
• Non-arthritic first MTP joint
• EHL bowstringing identified as the dynamic deforming force
• Failed conservative management

Contraindications

• Rigid deformity that does not correct passively
• Arthritic MTP joint
• Severe bone deformity requiring osteotomy
• Poor soft-tissue envelope

Set-up and approach. Supine, with a thigh (or ankle) tourniquet and a bump under the ipsilateral hip to bring the foot flat. A dorsal longitudinal incision of about 4-5 cm, centred over the joint line, runs from the midshaft of the first metatarsal to the midshaft of the proximal phalanx.

Steps

1. Incise skin and subcutaneous tissue, preserving the dorsal cutaneous nerves; the EHL lies in the centre of the wound. Open the extensor hood longitudinally over the MTP joint.
2. Transect the EHL sharply at the base of the proximal phalanx, distal to the MTP joint, and deliver the proximal stump into the wound with gentle traction; it retracts slightly but remains accessible.
3. Retract the tendon medially to expose the lateral capsule, identify the lateral collateral ligament and adductor hallucis insertion, and make a lateral capsulotomy if it is tight (the capsule is often attenuated in chronic varus).
4. Drill a 3.5-4 mm tunnel from dorsolateral to plantar-medial through the base of the proximal phalanx.
5. Place a heavy non-absorbable suture (e.g. No. 2 FiberWire) in the tendon with a Krackow or whipstitch and pass it through the tunnel from dorsolateral to plantar-medial.
6. Hold the hallux corrected, neutral to 5-10° of valgus, and tie the sutures over a button or post on the plantar-medial cortex, tensioning the EHL to the lateral side.

Alternatively, place a suture anchor in the lateral base of the proximal phalanx and suture the EHL to the lateral capsule and periosteum.

Adjuncts. Release abductor hallucis from the medial base of the proximal phalanx, through an extension of the incision or a separate medial one, and release the medial capsule if it is contracted. If significant medial angulation of the proximal phalanx persists after the soft-tissue correction, add a reverse Akin osteotomy.

Closure. Close the extensor hood loosely with absorbable suture, then the subcutaneous layer, and the skin with nylon or an absorbable subcuticular suture. A bulky dressing holds the hallux in slight valgus with gauze between it and the second toe.

Outcomes. None of the sources here gives a pooled success rate for the operation; its recurrence rate and other complications are set out under Complications.

First MTP Arthrodesis

Principle. Fusing the first MTP joint in a corrected position is a definitive solution that eliminates pain and corrects the deformity at the cost of joint motion. [14]

Indications

• Rigid hallux varus that does not correct passively
• Painful arthritis of the first MTP joint with varus deformity
• Salvage for failed soft-tissue procedures
• Severe deformity with bone and soft-tissue abnormalities

Contraindications

• Active infection
• Severe peripheral vascular disease
• Neuropathic foot (relative)
• A patient unwilling to accept loss of MTP motion

Set-up and approach. Supine with a bump under the ipsilateral hip and a thigh or ankle tourniquet. The dorsomedial approach is preferred: a longitudinal incision from mid-metatarsal to mid-proximal phalanx, centred just medial to the EHL tendon, gives good access to the joint, avoids crossing the EHL and minimises wound complications. Protect the dorsomedial cutaneous nerve branches, open the capsule longitudinally, expose the joint surfaces and release the collateral ligaments to mobilise the joint.

Joint preparation. Two options:

• Flat cuts: a sagittal saw makes cuts perpendicular to the long axis of each bone, the metatarsal head first and then the proximal phalanx base to match, removing cartilage and subchondral bone to bleeding cancellous bone with good apposition
• Conical reaming (cup-and-cone): reamers create a concave surface on one side and a convex surface on the other, giving a larger surface area, inherent stability and fine adjustment of alignment

Position. Critical to get right:

• 10-15° of valgus
• 20-25° of dorsiflexion relative to the ground with the ankle at neutral, which allows toe clearance in swing and heel rise in stance
• Rotation matched to the other side, the toenail pointing straight up
• No medial or lateral translation

Fusion Position is Critical

The most common error in first MTP arthrodesis is malposition. Too much dorsiflexion causes painful heel walking and pressure on the IP joint. Too little dorsiflexion causes difficulty with heel rise and shoe wear. Persistent varus fails to correct the deformity. Confirm dorsiflexion on lateral fluoroscopy with the foot plantigrade and the ankle at neutral, and valgus on AP fluoroscopy.

Fixation

• Dorsal plate, the most common current technique: a low-profile dorsal locking plate spanning the joint, with screws in the metatarsal and proximal phalanx and compression from a compression screw or the plate design. It gives rigid fixation and allows early weight-bearing.
• Crossed lag screws: two or three large (3.5-4.0 mm) screws crossing the fusion in different planes, giving compression and rotational stability with less prominent hardware
• Intramedullary screw, less common: a headless compression screw placed retrograde from the distal phalanx, with limited fixation strength and a higher nonunion rate

Closure. Irrigate, close the capsule if possible (it is often deficient), then the subcutaneous layer and skin, with a bulky dressing and posterior splint. Fusion typically takes 8-12 weeks; union rates and complications are under Complications.

In the case shown (Belfiore), rigid iatrogenic hallux varus was corrected by first MTP fusion with concomitant lesser-metatarsal procedures, and serial weight-bearing radiographs showed durable alignment at seven years.

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Reverse Akin Osteotomy

Principle. A lateral closing wedge osteotomy at the base of the proximal phalanx corrects medial angulation of the phalanx itself. It is the opposite of the traditional Akin osteotomy, a medial closing wedge for hallux valgus with lateral deviation of the distal phalanx. [16]

Indications

• Hallux varus with medial angulation of the proximal phalanx (interphalangeus varus)
• Usually as an adjunct to soft-tissue procedures (EHL transfer, abductor release)
• Congenital varus with bone deformity (delta phalanx)

Contraindications

• Severe osteopenia, because of the fracture risk
• Active infection
• Inadequate soft-tissue envelope

Approach. Use the same dorsal longitudinal incision centred over the first MTP joint as for the EHL transfer, retract the soft tissues to the base of the proximal phalanx and protect the neurovascular structures.

Steps

1. Mark the osteotomy at the base of the proximal phalanx, just distal to the MTP joint.
2. Cut a lateral closing wedge with an oscillating saw, base lateral (removing lateral bone) and apex medial.
3. Size the wedge to the correction needed, typically 2-4 mm at its base.
4. Close the wedge, bringing the lateral cortex to the medial cortex.
5. Fix with a single oblique screw from dorsal-distal to plantar-proximal, or two K-wires or a small staple, and close in layers as for the EHL transfer.

Outcomes. Union rates are high because the bone is metaphyseal, and the results are best when it is combined with soft-tissue balancing.

Correcting congenital varus. In the congenital correction illustrated (Manni), a dorsomedial release addressed the tethering abductor hallucis and capsule, and a valgus-producing first-metatarsal osteotomy with temporary MTP K-wire fixation restored alignment.

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The original operation. The classic Johnson transfer divides the whole EHL and reroutes it laterally, which removes active extension of the interphalangeal (IP) joint. To prevent the resulting cock-up or claw of the IP joint, Johnson combined it with a first IP arthrodesis, and that fusion is the price of the original operation.

The split modification. Only the lateral half of the EHL is detached and transferred laterally to correct the varus; the medial half is left intact and in continuity to keep extending the IP joint. This avoids the IP arthrodesis and preserves active IP extension, at the cost of a slightly weaker corrective vector from half the tendon. The Skalley series used it.

How to choose. The split transfer is favoured when preserving IP motion matters and the deforming force is not extreme. The complete transfer with IP fusion is kept for a strong dynamic deformity, or for an IP joint that is already stiff or arthritic, whose fusion is no loss. Either way the principle is the same: convert the EHL from a medial deformer into a lateral stabiliser.

Beyond the Johnson EHL transfer, Plovanich's systematic review and Schwagten's series describe the abductor hallucis (Hawkins), reverse abductor hallucis, extensor hallucis brevis (EHB, Myerson) and first dorsal interosseous (Valtin) transfers:

• Abductor hallucis (Hawkins) transfer, dynamic. Abductor hallucis is itself one of the medial deforming forces, so releasing it from the medial base and transferring it laterally removes a deformer and adds a lateral pull. It is an option when the EHL is not the dominant deformer, and it preserves the EHL entirely.
• Reverse abductor hallucis transfer, a static ligamentoplasty. The abductor hallucis, or a slip of it, becomes a static lateral tether recreating the deficient lateral collateral and adductor buttress. It spares the EHL and the IP joint, but modern long-term data (Schwagten: about 69% satisfaction at a mean of 4 years) show that late loss of correction can occur, and patients must be counselled.
• EHB (Myerson) transfer, dynamic and EHL-sparing. The EHB is transferred laterally as a dynamic corrector while the EHL is left intact, avoiding any loss of IP or MTP extension power.

How to choose. There are no comparative trials, so the choice rests on the dominant deforming force and on whether the EHL and IP joint are to be spared. An EHL-driven bowstring favours an EHL transfer, ideally split; a supple deformity where EHL preservation is wanted favours a reverse abductor ligamentoplasty or an EHB transfer. All are combined with the necessary medial release.

A joint-preserving alternative. The figures below, from one published report (Nekomoto), show reconstruction of the lateral collateral ligament with suture tape. Before surgery, standing views showed a hallux valgus angle of minus 24° with no intermetatarsal divergence, supporting a predominantly capsuloligamentous deformity. The bony medial prominence was reduced and the suture tape recentred the proximal phalanx over the metatarsal head. At one year the hallux valgus angle was 4° and the intermetatarsal angle 8°, with a congruent first MTP joint, maintained alignment and preserved active dorsiflexion and plantarflexion.

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Of the untreated deformity. Left alone, the deformity brings the transfer metatarsalgia, shoe difficulty and reduced push-off described in the Overview, with compensatory gait patterns. Abnormal joint mechanics accelerate degenerative change, and a flexible deformity often becomes rigid through capsular contracture.

General surgical complications

• Infection: 1-3% with standard precautions, higher in revision surgery or compromised soft tissues
• Wound healing problems: the dorsal foot has thin skin and limited vascularity, and the risk rises with multiple prior operations or smoking
• Nerve injury: the dorsal cutaneous nerves are at risk at the incision, causing numbness or a neuroma
• DVT and pulmonary embolism: rare in foot surgery, but consider prophylaxis in the high-risk patient

EHL transfer. Recurrent varus was reported in 4.4% (3 of 68 feet) in a systematic review that deliberately searched for failures, all after Johnson EHL transfer, which was also the commonest procedure in that series. The risk rises with inadequate transfer tension, poor patient selection (a rigid deformity) and failure to address all the deforming forces.

• IP extension weakness: the EHL normally extends the IP joint, so IP extension is weakened, usually well tolerated; transferring the whole tendon removes it altogether, which is why the original operation fused the IP joint and the split modification keeps half the tendon extending it
• Overcorrection to valgus: rare, when the transfer is too tight or combined procedures create excessive valgus force
• Tendon pull-out or failure, when fixation is inadequate; use a strong suture technique and a bone tunnel or solid anchor
• Wound healing issues

Arthrodesis. Roukis pooled 2,818 first MTP arthrodeses across 37 studies: union 94.6%, nonunion 5.4%, and only 32.7% of the nonunions symptomatic, a symptomatic nonunion rate of 1.8%. He states explicitly that the historical figure of about 10% is inaccurate. Nonunion is more likely with smoking, poor bone quality, inadequate fixation or infection. [15]

• Malunion: 6.1%, dorsal in 87% of those; fusion in the wrong position (too much or too little dorsiflexion, persistent varus, rotation) requires revision arthrodesis or osteotomy
• Hardware complications: prominent screws or plates causing irritation, with hardware removal in 8.5%
• Transfer metatarsalgia: loss of MTP motion shifts load to the lesser metatarsals; the mechanism is documented on pedobarography, but none of the sources here quantifies it after arthrodesis for hallux varus
• Hallux IP joint arthritis, from increased stress on the IP joint over time once MTP motion is lost
• Shortening, from excessive bone resection during joint preparation

Reverse Akin osteotomy

• Nonunion: rare in metaphyseal bone
• Malunion: an incorrect wedge size causing under- or overcorrection
• Fracture of the proximal phalanx in osteopenic bone or with trauma

Preventing recurrence after correction

1. Select correctly: flexible cases for soft-tissue procedures, rigid ones for arthrodesis.
2. Address every deforming force; an EHL transfer alone may fail if medial contractures are not released.
3. Fix securely: a strong suture technique for tendon transfers, rigid fixation for osteotomies.
4. Protect the correction with splinting while it heals.

The first two weeks. A bulky compressive dressing with gauze between the hallux and second toe holds the correction, with a posterior splint or CAM boot for protection and the foot elevated above heart level. Keep the dressing clean and dry; the first change, with suture removal, is at 10-14 days. Analgesia is multimodal: paracetamol, NSAIDs if not contraindicated for bone healing, and opioids as needed for the first few days.

Weight-bearing and motion follow the procedure:

After a reverse Akin osteotomy, protected weight-bearing in a stiff-soled shoe for 4-6 weeks, with radiographs at 2 and 6 weeks to assess healing.

Follow-up. Radiographs at 6 weeks, 12 weeks and 6 months check alignment, hardware and, after arthrodesis, union. Assess function (gait analysis, shoe wear, pain, satisfaction) and watch for recurrence, transfer metatarsalgia and hardware prominence.

What the illustrated cases show. After congenital correction (Manni), the hallux remained centred at six weeks after temporary stabilisation, when wound condition and maintenance of correction are checked before mobilisation is advanced; at six months it remained aligned without recurrent medial drift, the early clinical goal after release and osteotomy. In the adult case report (Ortiz-Romero), standing alignment remained plantigrade at 48 months, with the hallux centred and the first web space restored under load.

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Global epidemiology:

• Hallux varus is uncommon worldwide; the dominant aetiology in adults is iatrogenic overcorrection after hallux valgus surgery, reported across surgical series at roughly 2-13% depending on technique and definition.
• Reported cohorts are overwhelmingly female, mirroring the demographics of bunion surgery.
• Congenital cases are rare and have equal sex distribution; traumatic/burn-related cases follow injury patterns and are over-represented in lower-resource and high-burn-incidence regions.

Guidance and consensus (no dedicated single-society guideline exists):

1. Mann RA, Coughlin MJ. Hallux varus. In: Mann RA, Coughlin MJ, editors. Surgery of the Foot and Ankle. 6th ed. St. Louis: Mosby; 1993. p. 321-334.

2. Coughlin MJ, Saltzman CL, Anderson RB. Mann's Surgery of the Foot and Ankle. 9th ed. Philadelphia: Elsevier; 2014.

3. Edelman RD. Iatrogenic hallux varus. Foot Ankle Surg. 2015;21(4):223-227. doi:10.1016/j.fas.2015.07.003

4. Farmer AW. Congenital hallux varus. Am J Surg. 1958;95(2):274-278. doi:10.1016/0002-9610(58)90515-4

5. Hutton WC, Dhanendran M. The mechanics of normal and hallux valgus feet: a quantitative study. Clin Orthop Relat Res. 1981;(157):7-13.

6. Hawkins FB. Acquired hallux varus: cause, prevention and correction. Clin Orthop Relat Res. 1971;76:169-176.

7. Skalley TC, Myerson MS. The operative treatment of acquired hallux varus. Clin Orthop Relat Res. 1994;(306):183-191.

8. McElvenny RT. Hallux varus. Q Bull Northwest Univ Med Sch. 1941;15:277-280.

9. Johnson KA, Spiegl PV. Extensor hallucis longus transfer for hallux varus deformity. J Bone Joint Surg Am. 1984;66(5):681-686.

10. Shereff MJ, Bejjani FJ, Kummer FJ. Kinematics of the first metatarsophalangeal joint. J Bone Joint Surg Am. 1986;68(3):392-398.

11. Coughlin MJ, Roger A. Mann Award. Juvenile hallux valgus: etiology and treatment. Foot Ankle Int. 1995;16(11):682-697.

12. Johnson KA, Spiegl PV. Extensor hallucis longus transfer for hallux varus deformity. J Bone Joint Surg Am. 1984;66(5):681-686.

13. Citation unverifiable - do not rely on it. This slot previously read "Chacon YP, Lam T. Extensor hallucis longus transfer for correction of hallux varus: long-term follow-up. J Foot Ankle Surg. 2012;51(6):687-691". No such paper could be found: J Foot Ankle Surg 2012;51(5):687-689 is Sundararajan PP, "Combined arthroscopic and fluoroscopic guidance in the atraumatic treatment of posterior ankle impingement syndrome" (PMID 22766192), an unrelated subject, and the quoted DOI does not resolve to the described article. Every claim that formerly cited this reference has been rewritten to rest on a verified source.

14. Coughlin MJ, Abdo RV. Arthrodesis of the first metatarsophalangeal joint with Vitallium plate fixation. Foot Ankle Int. 1994;15(1):18-28. doi:10.1177/107110079401500105

15. Roukis TS. Nonunion after arthrodesis of the first metatarsophalangeal joint: a systematic review. J Foot Ankle Surg. 2011;50(6):710-713. doi:10.1053/j.jfas.2011.06.010

16. Akin OF. The treatment of hallux valgus: a new operative procedure and its results. Med Sentinel. 1925;33:678-683.

17. Vandeputte G, Dereymaeker G, Steenwerckx A, Peeraer L, Broos P. The Weil osteotomy of the lesser metatarsals: a clinical and pedobarographic follow-up study. Foot Ankle Int. 2000;21(5):370-374. doi:10.1177/107110070002100502

18. Leemrijse T, Hoang B, Maldague P, Docquier PL, Valtin B. A new surgical procedure for iatrogenic hallux varus: reverse transfer of the abductor hallucis tendon. A report of 7 cases. Acta Orthop Belg. 2008;74(2):227-234.

19. Politi J, John H, Njus G, Bennett GL, Kay DB. First metatarsal-phalangeal joint arthrodesis: a biomechanical assessment of stability. Foot Ankle Int. 2003;24(4):332-337. doi:10.1177/107110070302400408