DEFINITION

Hallux valgus is a static subluxation of the first metatarsophalangeal (MTP) joint with medial deviation of the first metatarsal and lateral or valgus rotation of the hallux. A medial or dorsomedial prominence is present and usually called a bunion.

The development of hallux valgus is debated but occurs almost exclusively in shod populations.10,15,18

Other causes that may contribute to a hallux valgus deformity include heredity,4,6,14,27 pes planus,8,9,11,20,22 metatarsus primus varus,9,25 systemic arthritis,16,21,26 neuromuscular disorders, excessive roundness of the metatarsal head,2 and abnormal obliquity of the first tarsometatarsal joint.13

Hypermobility may also be another causative factor in the formation of a bunion, and a first metatarsal-cuneiform joint fusion may be an appropriate alternative procedure.

Hallux valgus can lead to painful motion of the joint or difficulty with footwear.

Surgical correction of bunion deformity is a common procedure. For larger deformities, a proximal osteotomy of the first metatarsal is required. The Mau proximal osteotomy technique is an accepted and proven technique. This osteotomy has the advantage over other proximal osteotomies of being inherently stable, having a reproducible surgical technique, and minimizing the common complications of other proximal osteotomies.

 

ANATOMY

 

The first MTP joint is two joints with a ball-and-socket type of joint between the first metatarsal and proximal phalanx. The second portion is a groove on the plantar first metatarsal that articulates with the dorsal surface of two sesamoids. These joints share a common capsule and interrelated muscles.

 

Collateral ligaments are fan-shaped ligaments that originate from the medial and lateral epicondyles of the first metatarsal head. These ligaments run vertical, horizontal, and oblique from the first metatarsal head, proximal phalanx, and sesamoids.

 

The sesamoids (medial and lateral) are separated by a rounded ridge (crista) and are connected by the intersesamoidal ligament. The lateral sesamoid is also connected to the plantar plate of the second metatarsal head by the transverse intermetatarsal ligament. In addition to collateral ligament attachments, each sesamoid is contained by a separated tendon of the flexor hallucis brevis muscle.

 

Intrinsic muscles that insert on the proximal phalanx are the abductor hallucis (plantar medial) and the oblique-transverse head of the adductor hallucis (plantar lateral phalanx). Both of these tendons also blend in with the

flexor hallucis brevis to invest each corresponding sesamoid. These intrinsic muscles act to maintain the alignment of the hallux and balance the forces of each other.

 

Extrinsic muscles include the flexor hallucis longus (FHL) and extensor hallucis longus (EHL). The FHL lies within a groove plantar to the intersesamoidal ligament. It proceeds distally to insert into the base of the distal phalanx. The EHL runs over the dorsal surface of the proximal phalanx and inserts into the base of the distal phalanx. Over the first MTP, the EHL is anchored to the sesamoids by the extensor sling.

 

PATHOGENESIS

 

The development of hallux valgus varies depending on the causative factor.

 

The function of the abductor hallucis muscle is to plantarflex, adduct, and invert the proximal phalanx. The reverse is true for the adductor hallucis muscle. When these muscles act together, a straight plantarflexion force is produced and the transverse-frontal plane forces are neutralized.

 

When the adductor hallucis muscle gains the mechanical advantage, such as in removing the tibial sesamoid or pronation, a hallux valgus deformity may ensue. The sesamoids are pulled laterally, thus eroding the crista. The metatarsal head is pushed medially, stretching the medial ligaments, and the abductor hallucis slides beneath the metatarsal head, pronating the hallux.

 

As the deformity progresses, the EHL and FHL have been shown to become a dynamic deforming force.

 

NATURAL HISTORY

 

The progression of a hallux valgus deformity is usually gradual, but when multiple causative factors are present, progression can be more rapid.

 

As the deformity progresses, the hallux drifts laterally and either over or under a stable second digit. Over time, the second MTP joint can dislocate.

 

As the hallux drifts laterally, it assumes less weight bearing, and a diffuse callus may occur underneath the second metatarsal head.

 

PATIENT HISTORY AND PHYSICAL FINDING

 

The chief compliant of a bunion deformity is usually pain. Pain can be located over several areas in a bunion deformity: median eminence, dorsal first MTP joint, medial or lateral sesamoids, or impingement on the second digit.

 

A thorough general medical history may include gout, osteoarthritis, rheumatoid arthritis, diabetes, or peripheral vascular disease.

 

 

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Other important factors include style of shoes and if any shoe gear modification has been attempted, physical activity of the patient, and occupational demands.

 

Patient expectations are also important. Goals of surgery should include increasing activity and decreasing pain. Forewarning the patient of limitations after surgery is necessary, such as the possibility of not returning to tight fashionable shoes.

 

The physical examination should start with the patient weight bearing to assess the bunion and lesser toe deformities and compare them to the other foot.

 

Evaluation of the vascular status is important. The perfusion is determined by palpating the posterior tibial and dorsal pedis arteries. Perfusion of a digit can be assessed by the capillary refill. Appropriate vascular studies

such as transcutaneous oxygen, ankle-brachial index, digital pressures, and segmental pressures are useful when perfusion to the foot is in doubt.

 

The first MTP joint range of motion is assessed for crepitus, pain, or impingement if a dorsal spur is present. Motion is also assessed with the hallux in a corrected position to determine the degree of associated contracture of the soft tissues. Normal range of motion is 70 to 90 degrees of dorsiflexion. Joint range of motion is compared to that of the opposite foot.

 

Transverse plane mobility is assessed by distracting the hallux while the metatarsal head is pushed laterally to see clinical reduction of the intermetatarsal angle.

 

The median eminence is assessed for its prominence and underlying bursa. Neuritic pain can be elicited from the nearby dorsal or plantar cutaneous nerves.

 

The tibial and fibular sesamoids are directly palpated while putting the joint through a range of motion to indicate intraarticular derangement.

 

The first tarsometatarsal joint excursion is assessed by grasping proximal to this joint and moving the first metatarsal and comparing it to the opposite foot. Normal range of motion is 10 mm of excursion. A hypermobile first ray is more than 15 mm of excursion.

 

Range of motion of the hallux interphalangeal joint is evaluated in the transverse and sagittal plane as well as joint quality.

 

Pain may also occur from lesser toe deformities or transfer lesions that may accompany the bunion deformity. A symptomatic intractable plantar keratoma beneath the second metatarsal head is present in the majority of

patients.17 Other associated problems include neuromas, corns, and tailor's bunion.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

The radiologic examination should include weight-bearing lateral, anteroposterior (AP), and oblique views (FIG 1).

 

Several measurements are obtained using these radiographs to determine the severity of the bunion deformity, including the intermetatarsal 1-2 angle (IM 1-2), hallux valgus angle (HVA), tibial sesamoid position, distal metatarsal articular angle (DMAA), and congruency of the first MTP joint.

 

 

The IM 1-2 angle is determined by measuring the angle subtended by the lines bisecting the longitudinal axis of the first and second metatarsals.

 

Normal is less than 9 degrees (FIG 2A).

 

The HVA is determined by measuring the angle subtended by the lines bisecting the first metatarsal and proximal phalanx of the hallux.

 

 

Normal is 15 degrees or less (FIG 2B).

 

 

 

FIG 1 • A,B. Preoperative weight-bearing AP and lateral foot radiographs.

 

 

Tibial sesamoid position describes the relationship of the tibial sesamoid to the bisection of the first metatarsal.

 

 

The position of the sesamoid is determined by a numerical sequence of one to seven with increasing deformity.

 

Normal is a position of one to three (FIG 2C).

 

The DMAA is the angle subtended by a line representing the articular cartilage of the first metatarsal head and a perpendicular line to the bisection of the shaft of the first metatarsal.

 

 

Normal measures are less than 8 degrees (FIG 2D).

 

An increase in the DMAA may demonstrate a structural deformity in the head of the metatarsal.

 

The first MTP joint may be described as congruent, deviated, or subluxed.

 

A congruent joint is one in which the cartilage surfaces of the first metatarsal head and proximal phalanx are parallel.

 

 

A deviated joint is one in which the cartilage lines intersect at a point outside of the joint. In a subluxed joint, the cartilage lines intersect within the joint (FIG 2E).

Degenerative arthritis at the first MTP joint can be evaluated on each weight-bearing radiograph.

DIFFERENTIAL DIAGNOSIS

Metatarsus primus varus Hallux varus

Gout

Hallux rigidus

 

 

NONOPERATIVE MANAGEMENT

 

Conservative treatment options for hallux valgus deformities are limited.

 

Shoe wear modifications such as an extra wide and deep toe box can help accommodate the deformity. Also, a soft upper leather can be stretched over the bunion to provide accommodation.

 

 

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FIG 2 • A. The IM angle measures the splay between the first and second. B. The HVA measures the angle formed between the proximal phalanx and first metatarsal. C. The tibial sesamoid position describes the position of the tibial sesamoid relative to the bisection of the first metatarsal. D. The DMAA measures the relationship of the articular surface of the first metatarsal head to the bisection of the first metatarsal. E. A deviated joint in which the articular surfaces are not parallel with each other.

 

 

 

Custom-made shoes may help individuals reluctant or unable to undergo a surgical procedure. Bunion pads, night splints, and toe spacers tend to be of little use.

 

A custom-made orthosis may be beneficial if an associated flatfoot deformity is present. The use of an orthosis has not been demonstrated to prevent a hallux valgus deformity or slow its progression. Others have proposed using orthoses postoperatively to prevent recurrence.

 

SURGICAL MANAGEMENT

 

Bunions can be classified by their severity. This classification is used to facilitate the decision-making process

of how to treat the deformity.

 

 

Mild bunion: HVA less than 20 degrees, congruent joint, IM angle less than 11 degrees. Pain is usually due to a medial eminence.

 

Moderate bunion: HVA 20 to 40 degrees, incongruent joint, IM angle 11 to 18 degrees. The hallux is usually pronated and presses against the second digit.

 

Severe bunion: HVA more than 40 degrees, subluxed joint, IM angle more than 18 degrees. Hallux is often overriding or underlapping the second digit; painful transfer lesion underneath the second metatarsal head; possible arthritic changes to the first MTP joint.

 

The indications for hallux valgus surgery using the Mau osteotomy include the following:

 

 

 

Painful moderate to severe bunion deformity Deformity unresponsive to conservative treatment

 

The authors frequently use the Mau osteotomy also to correct painful tailor's bunion deformities of the fifth metatarsal. The advantages and technical ease of the osteotomy directly translate to the successful use of the Mau osteotomy for the fifth metatarsal.

 

The indications for tailor's bunion surgery using the Mau osteotomy include the following:

 

 

Painful, moderate to severe tailor's bunion deformity with an enlarged lateral exostosis and an increased intermetatarsal 4-5 angle

 

Deformity unresponsive to conservative treatment

 

 

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FIG 3 • A well-padded thigh tourniquet set to 300 mm Hg.

 

Preoperative Planning

 

Routine preoperative clearance is obtained via history and physical assessment. This may include an electrocardiogram, chest radiograph, and laboratory workup.

 

A prophylactic antibiotic of choice is given 30 minutes before the procedure. Also, one tablet of 200 mg celecoxib (Celebrex) is given.

 

 

 

FIG 4 • A. Two-incision approach for Mau osteotomy and distal soft tissue procedure. B. Medial incision starts at the first tarsometatarsal joint and courses distal and medially for the distal soft tissue procedure.

 

Positioning

 

 

The patient is placed supine on the operating table with a bump placed under the contralateral hip. A well-padded pneumatic thigh tourniquet is used and set to 300 mm Hg (FIG 3).

Approach

 

Typically, two incisions are used to provide adequate exposure.

 

 

The first incision is placed over the first web space and the second is placed on the medial aspect of the first metatarsal (FIG 4A).

 

The second incision starts at the first tarsometatarsal joint and courses distally and medially over the first MTP joint for the medial eminence resection and plication of the capsule (FIG 4B).

 

TECHNIQUES

• Lateral Release of the First Metatarsophalangeal Joint

Using an incision in the first web space (TECH FIG 1A), perform the lateral release first. Carry dissection through the subcutaneous layer.

Typically, the first structure incised is the superficial portion of the transverse ligament.

 

 

 

 

TECH FIG 1 • A. The first structure identified in a lateral release is the superficial portion of the deep transverse metatarsal ligament. B. Blunt dissection is carried deep to identify and release the adductor hallucis tendon.

 

 

Use blunt dissection to view the lateral first MTP joint and fibular sesamoid.

 

Release the adductor tendon from the plantar-lateral base of the proximal phalanx and fibular sesamoid (TECH FIG 1B).

 

 

Incise the deep portion of the transverse ligament. The lateral capsule of the first MTP joint is “pie crusted,” and a varus stress is placed on the joint.

 

• Medial Capsulorrhaphy

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  Using a standard medial approach, perform an inverted L-shaped capsulotomy. The alternative dorsal-medial skin incision, which is placed over the first dorsal metatarsal artery and nerve, can cause nerve irritation and entrapment.

   

  This allows exposure of the enlarged medial eminence and release of the stretched medial sesamoid suspensory ligament (TECH FIG 2A). Remove the periosteum from the metatarsal head medially and dorsally but keep it intact at the neck plantarly to preserve the nutrient artery.

   

   

   

  TECH FIG 2 • A. Release of the stretched medial sesamoid suspensory ligament. B. Minimal exostectomy of the medial eminence.

   

   

  Resect the medial eminence using a sagittal saw (TECH FIG 2B).

   

  Take the eminence from dorsolateral to plantar-medial. Remove the eminence in this orientation to prevent staking of the metatarsal head and loss of the sagittal groove, which can lead to medial subluxation of the tibial sesamoid and promote hallux varus.

• Mau Osteotomy

Exposure

 

Carry the dissection deep to the first metatarsal shaft.

 

The skin incision can be placed slightly plantar to the first metatarsal to avoid surrounding neurovascular structures such as the first dorsal metatarsal artery and nerve. With this incision, a potentially nonpainful scar results, as the incision is not placed directly over bone. The EHL tendon is not encountered with this incision and is retracted safely.

 

Identify the first tarsometatarsal joint, but do not disturb the capsule. An 18-gauge needle can be placed in the joint for reference.

 

Starting 1 cm from the first tarsometatarsal joint, reflect the periosteum plantar-proximal to dorsal-distal only in line with the osteotomy, thereby preserving the rest of the periosteum (TECH FIG 3).

 

Much of the periosteum is retained to promote adequate bone healing.

Osteotomy

 

The osteotomy does not incorporate the entire metatarsal shaft as does the traditional Mau osteotomy. The osteotomy ends in the midshaft of the first metatarsal.

 

Complete the osteotomy with a sagittal saw parallel to the weight-bearing surface to prevent unwanted dorsal angulation of the first metatarsal.

 

The Mau is started proximal-plantar and ends distal-dorsal (TECH FIG 4 A,B).

 

A self-retaining retractor is useful to protect the surrounding neurovascular and tendinous structures.

 

 

 

TECH FIG 3 • Identification of the first tarsometatarsal joint (star) and starting point of the osteotomy 1 cm distal to the joint (Freer elevator).

 

 

Using the straight medial incision avoids tendinous structures and allows excellent visualization of the medial metatarsal shaft to complete the osteotomy.

 

To maintain complete control while completing the osteotomy, a smooth guide pin for the selected cannulated screw can be placed perpendicular across the completed proximal portion of the osteotomy. Then, the osteotomy can be completed without fear of losing the orientation.

 

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TECH FIG 4 • A. The osteotomy is placed parallel to the weight-bearing surface of the foot and the osteotomy is completed from proximal-plantar to distaldorsal. B. The traditional Mau osteotomy (red line) and the slight modification (black line). The modified Mau does not incorporate the entire metatarsal shaft as does the traditional Mau osteotomy. The modified Mau osteotomy with two-screw fixation.

Reduction and Fixation

 

After completing the osteotomy, rotate the distal fragment.

 

Optimal rotation of the osteotomy may be facilitated by placing a large reduction bone clamp on the first metatarsal head and neck of the second metatarsal to help reduce the IM 1-2 angle (TECH FIG 5A).

 

Place two temporary Kirschner wires (0.025 inch) from dorsal to plantar perpendicular to the osteotomy site (TECH FIG 5B).

 

Reduction of the IM 1-2 angle is mostly obtained by rotation of the distal fragment. It is acceptable to allow slight lateral translation of the distal fragment relative to the proximal fragment to further correct the IM angle.

 

 

 

TECH FIG 5 • A. Fluoroscopic image showing reduction of IM 1-2 angle with large reduction bone clamps. The clamp is placed medially at the first metatarsal head and laterally around the second metatarsal head. B. Temporary fixation of the osteotomy with two parallel Kirschner wires from dorsal to plantar. C. Intraoperative fluoroscopy of AP foot, showing final fixation and excellent reduction of the IM 1-2 angle. D. Lateral intraoperative fluoroscopy demonstrating parallel headless screw fixation following Mau osteotomy. E. Final fixation of Mau osteotomy with two 3.0-mm cannulated headless screws.

 

 

We recommend using intraoperative fluoroscopy to confirm proper position of the first metatarsal head over the tibial sesamoids, congruent joint alignment, and satisfactory orientation of the osteotomy (TECH FIG 5C,D).

 

We use a towel clip to provisionally advance the capsule into the desired position to assess sesamoid alignment.

 

Redundant capsular tissue is excised, and optimal correction is obtained with a tibial sesamoid position less than 2 and an IM 1-2 angle less than 9 degrees.

 

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About 4 mm of redundant capsule is removed from the inverted L-shaped portion of the capsulotomy to help reduce and advance the sesamoids upon closure.

 

With larger deformities, more capsule may need to be removed to reduce the tibial sesamoid position adequately.

 

To correct pronation of the hallux, the towel clip can be rotated to correct the deformity, and a double simple suture is placed to maintain the correction.

 

We use two 2.5- or 3.0-mm headless cannulated screws for final fixation (TECH FIG 5E).

• Closure

   

  To complete the medial capsulorrhaphy, close the capsule using a double simple suture or pants-over-vest technique with 0-0 absorbable suture (TECH FIG 6A).

   

  Placing a sponge in the first interspace while closing the capsule will splint the toe in the corrected

  position.

   

  Close the subcutaneous layer with 2-0 absorbable suture. The skin is closed based on the surgeon's preference, with either a running subcuticular closure with 3-0 absorbable suture or simple interrupted sutures with 3-0 nylon (TECH FIG 6B).

   

   

   

  TECH FIG 6 • A. Completion of the medial capsulorrhaphy with pants-over-vest technique with 0-0 absorbable suture. B. Final skin closure with running subcuticular 3-0 absorbable suture.

   

   

  Place a soft toe spica dressing by dividing a sponge in thirds and wrapping lateral to medial around the hallux to maintain correction. Use caution to prevent aggressive splinting, which can cause overcorrection and potential hallux varus.

• Use of the Mau Osteotomy from Correction of Tailor's Bunion Deformities of the Fifth Metatarsal

Exposure

 

 

One incision is used along the lateral aspect of the fifth metatarsal (TECH FIG 7A). Dissection is carried through the skin and subcutaneous tissues.

 

A longitudinal capsular incision is made and the periosteal tissues are released around the fifth metatarsal head and the distal third of the fifth metatarsal (TECH FIG 7B).

Osteotomy, Fixation, and Completion

 

The planned osteotomy is directed in a dorsal-distal to proximalplantar direction starting at the neck of the metatarsal to the mid-diaphysis (TECH FIG 8A).

 

The osteotomy is then completed with a microsagittal saw.

 

The distal fragment of the osteotomy is then translated medially and temporarily fixated using two guidewires of choice (TECH FIG 8B).

 

 

Final fixation is then achieved with two parallel, 2.5-mm cannulated headless screws (TECH FIG 8C). Standard wound closure is performed with absorbable and nonabsorbable sutures.

 

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TECH FIG 7 • A. Lateral skin incision for approach to the distal fifth metatarsal. B. Exposure of the distal third of the fifth metatarsal.

 

 

 

TECH FIG 8 • A. Mau osteotomy of the fifth metatarsal (dotted line) oriented dorsal-distal to proximal-

plantar. B. Temporary fixation using two parallel guidewires for cannulated screw fixation. C. Intraoperative fluoroscopy demonstrating final fixation using two parallel cannulated screws.

 

 

 

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PEARLS AND PITFALLS

 

Incision ▪ Incision is placed medial to the first metatarsal and slightly plantar to avoid the surrounding neurovascular structures. This allows fast deep dissection.

 

Medial capsulorrhaphy

• Placing a varus stress on the hallux will expose redundant capsular tissue that can be incorporated within the L-shaped portion of the capsulotomy and can be adequately removed.

   

  Osteotomy ▪ The periosteum is elevated only in line with the osteotomy. The proximal portion of the osteotomy should be at least 1 cm distal from the first tarsometatarsal joint. This will also prevent placement of the osteotomy within the first tarsometatarsal joint.

  • The saw blade is kept parallel to the weight-bearing surface of the foot to prevent unwanted dorsal angulation of the first metatarsal head after completion of the osteotomy.

  • To maintain complete control of the osteotomy, a guidewire for the cannulated screw can be placed perpendicular in the completed proximal portion of the osteotomy. The osteotomy can be completed dorsal-distally without fear of losing the orientation.

     

    IM 1-2

    reduction

    • Reduction can be achieved with large reduction clamps or by using a Freer elevator on the lateral portion of the proximal fragment and placing counterpressure on the first metatarsal head. Intraoperative fluoroscopy is recommended after placing temporary fixation to achieve an IM angle less than 9 degrees.

       

      Screw placement

    • Placing a screw too distal may cause fracture of the dorsal portion of the osteotomy site. Allow adequate space between the screws and the distal aspect of the osteotomy to prevent fracture.

     

    Unrecognized hypermobility of the first tarsometatarsal joint

• This may result in the inability to effectively reduce the IM 1-2 angle after temporary fixation. If encountered, the first tarsometatarsal joint may be temporarily pinned and permanent fixation placed. The pin across the first tarsometatarsal joint can be removed 4-6 weeks postoperatively.

 

POSTOPERATIVE CARE

Standard Mau Osteotomy

 

The patient is placed in a well-padded posterior splint after surgery and instructed to remain non-weight bearing with an assistive device until the first postoperative visit 7 to 10 days following surgery.

 

Seven to 10 days after surgery, the sutures are removed, and the patient is fully weight bearing in a below-knee immobilizing boot.

 

Three weight-bearing radiographs (AP, lateral, oblique) are obtained at each visit until bony healing of the osteotomy site is seen typically between 5 and 6 weeks.

 

A removable compression and control strap is prescribed at this point to splint the hallux in a neutral position as the patient transitions to regular shoe gear.

 

Physical therapy is instituted at 6 weeks postoperative, as the transition from the walking boot to shoes occurs.

 

Light activities are permitted until approximately 12 weeks postoperative when full sport may be resumed.

 

Mau Osteotomy of the Fifth Metatarsal

 

The patient is placed in a well-padded non-weight-bearing posterior splint for approximately 7 to 10 days.

 

Suture removal occurs at the first postoperative visit at 7 to 10 days and the patient is transitioned into a weight bearing below-knee immobilizing boot.

 

The weight-bearing boot is maintained until bony consolidation occurs typically at 5 to 6 weeks postoperative.

 

 

OUTCOMES

After a proximal osteotomy and distal soft tissue release, 90% to 95% patient satisfaction rates have been reported.3,5,17

One study reviewed retrospective results of the Mau osteotomy and found excellent correction of a moderate to severe bunion deformity in 24 patients.7

A recent retrospective review of 23 patients found a significant improvement in American Orthopaedic Foot and Ankle Society (AOFAS) scores from 47 preoperatively to 92 postoperatively. Additionally, hallux abducto valgus and intermetatarsal angles demonstrated a statistically significant improvement. No

complications of nonunion or undercorrection were encountered.23

Data has also been shown to advocate the use of a Mau-Reverdin double metatarsal osteotomy for the correction of hallux valgus. A high rate of satisfaction with AOFAS scores and a statistically significant

improvement of radiographic angles were shown from preoperative to postoperative.19

Biomechanical studies using sawbones and fresh frozen cadaver models showed superior stability with the Mau osteotomy in terms of fatigue, strength, and stiffness compared to other proximal

osteotomies.1,24 The Mau osteotomy is an inherently stable osteotomy that allows early postoperative weight bearing without the need for cast immobilization as required for other proximal osteotomies due to complications such as dorsal malunion and nonunion. The Mau is a stable osteotomy due to the dorsal shelf to help reduce dorsal displacement forces and broad bony apposition to facilitate two-screw fixation.

The authors performed a follow-up study comparing the Mau and crescentic osteotomies. Both osteotomies showed comparable correction of the moderate to severe bunion deformity, but significantly, more complications were associated with the crescentic osteotomy. Complications included dorsal

 

malunion, placement of screws within the tarsometatarsal joint, and nonunion.12

 

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FIG 5 • A. Preoperative weight-bearing appearance of the bunion deformity of the patient in FIG 1. B. Final postoperative appearance closure with 3-0 suture. C,D. Postoperative AP and lateral foot radiographs showing excellent reduction of the IM 1-2 angle.

 

 

The Mau osteotomy is technically easier to perform than other proximal osteotomies with fewer complications, as seen in multiple studies and excellent correction of a bunion deformity (FIG 5 A-D).

 

COMPLICATIONS

One of the most common complications after bunion surgery is recurrence. This may be due to selection of the inappropriate procedure to correct the moderate to severe bunion deformity or intraoperative failure to obtain an adequate alignment to correct the deformity.

Hallux varus is a complication that occurs less often than recurrence. It occurs as a result of overcorrection of the deformity and is much more difficult to correct.

Other complications include shortening, dorsal malunion, and transfer lesions, which can occur with all proximal osteotomies.

 

REFERENCES

1. Acevedo JI, Sammarco VJ, Boucher HR, et al. Mechanical comparison of cyclic loading in five different first metatarsal shaft osteotomies. Foot Ankle Int 2002;23:711-716.

    

    

2. Brahm SM. Shape of the first metatarsal head in hallux rigidus and hallux valgus. J Am Podiatr Med Assoc 1988;78:300-304.

    

    

3. Chiodo C, Schon L, Myerson MS, et al. Clinical results with the Ludloff osteotomy for correction of adult hallux valgus. Foot Ankle Int 2004;25:532-536.

    

    

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

    

    

5. Easley ME, Kiebzak GM, Davis WH, et al. Prospective, randomized comparison of proximal crescentic and proximal chevron osteotomies for correction of hallux valgus deformity. Foot Ankle Int 1996;17: 307-316.

    

    

6. Ellis VH. A method of correcting metatarsus primus varus; preliminary report. J Bone Joint Surg Br 1951;33-B(3):415-417.

    

    

7. Glover JP, Hyer CF, Berlet GC, et al. Early results of the Mau osteotomy for correction of moderate to severe hallux valgus. J Foot Ankle Surg 2008;47:237-242.

    

    

8. Greenburg GS. Relationship of hallux abductus angle and first metatarsal angle to severity of pronation. J Am Podiatr Assoc 1979;69: 29-34.

    

    

9. Hardy RH, Clapham JC. Observations on hallux valgus; based on a controlled series. J Bone Joint Surg Br 1951;33-B(3):376-391.

    

    

10. Hoffman P. Conclusions drawn from a comparative study of the feet of barefooted and shoe-wearing peoples. Am J Orthop Surg 1905;3: 105-136.

     

     

11. Hohmann G. Der hallux valgus und die uebrigen Zchenverkruemmungen. Ergeb Chir Orthop 1925;18:308-348.

     

     

12. Hyer CF, Glover JP, Berlet GC, et al. A comparison of crescentic and Mau osteotomies for correction of hallux valgus. J Foot Ankle Surg 2008;47:103-111.

     

     

13. Hyer CF, Philbin TM, Berlet GC, et al. The obliquity of the first metatarsal base. Foot Ankle Int 2004;25:728-732.

     

     

14. Johnston O. Further studies of the inheritance of hand and foot anomalies. Clin Orthop 1956;8:146-160.

     

     

15. Kato T, Watanabe S. The etiology of hallux valgus in Japan. Clin Orthop Relat Res 1981;(157):78-81.

     

     

16. Kirkup JR, Vidigal E, Jacoby RK, et al. The hallux and rheumatoid arthritis. Acta Orthop Scand 1977;48:527-544.

     

     

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