Problem: In order for the most effective surgical procedure to be chosen, the deformity must be carefully characterized.

Frequency: In the United States, the number of forefoot operations is markedly higher in females when analyzing the 3 most common forefoot ailments (HV, hammertoe, neuroma). This was attributed to differences in footwear (Coughlin, 1995; Frey, 1993).

Etiology: Coughlin and associates have made the connection between shoes that are too narrow and forefoot complaints in women (Coughlin, 1995; Frey, 1993).

Clinical: Patient demands, footwear, and expectations should be assessed prior to treating the patient with a bunion deformity. Obviously, a directed history and physical examination should be performed to address vascular status, possible neuropathies, and medical comorbidities. Activity level must be assessed as the high-demand athletic patient may place more emphasis on mobility of the joint than deformity correction. Finally, footwear must be addressed. A good radiographic result does not translate necessarily to unrestricted footwear use; Mann reported that only 59% of his patients had unrestricted footwear use after bunion correction.

For indications for specific surgical procedures used to address HV and bunion deformity.

Once footwear modifications (e.g. shoes with a rounded and enlarged toe box) have failed to relieve the pain that comes with the deformity, surgical correction may be offered to the patient.

The second characteristic that contributes to HV is the orientation of the articular surface of the MT head in relation to the long axis of the first MT (Richardson, 1993) (see Picture 1). The distal metatarsal articular angle (DMAA) describes the lateral slope of the articular surface in relation to the long axis of the first MT. Normally, the DMAA is less than 10°. Surgical decision-making must take into account an increased DMAA angle.

The orientation of the great toe is also determined by the proximal phalanx articular angle (PPAA). This is the angle formed by the intersection of a line along the long axis of the PP and a line along the proximal joint surface of the PP. Deformity at this level contributes to an increased valgus deformity of the first toe; however, the deformity is expressed at the IPJ rather than the MTPJ. The importance of the DMAA and PPAA cannot be underestimated because these angles reflect the lateral inclination of the joint. Correction of these angles must be a goal of any surgery chosen to address the bunion deformity.

MTPJ congruence is another factor that is considered when choosing a procedure for bunion correction. The congruence of the joint is determined by combining the PPAA and the DMAA. The lines drawn parallel to the joint surface of both the PP and the first MT head should be parallel. When the lines are parallel, a congruent joint exists. When they are not parallel, an incongruous or subluxed joint exists. This relationship is important to consider when choosing the surgical procedure; intraarticular procedures (ie, distal soft tissue realignment [DSTR]) should not be used with a congruent joint that has an increased DMAA and/or increased PPAA.

Congruent joints with an increased DMAA must be addressed with extraarticular procedures (ie, osteotomies) in order to prevent converting a congruent joint to an incongruent joint. An incongruent joint, because of the unusual stresses on the joint would be more prone to development of osteoarthritic changes.

The 2 angles most commonly involved in HV deformity are the hallux valgus angle (HVA) and the 1-2 intermetatarsal angle (IMA). The HVA is formed by the intersection of the lines along the long axis of the PP and the first MT. This angle is measured easily. The normal angle should be less than 15°. The next important measurement is the angle formed by the intersecting long axis lines along the first and second MTs (1-2 IMA). Normally this angle should be less than 9°.

The final joint that must be assessed carefully is the MTC joint. The shape and orientation of this joint vary and affect the medial inclination for the first MT. It is difficult to make reliable radiographic measurements of this joint because these measurements can vary depending on the plane of the x-ray beam. Excessive obliquity is associated with hypermobility instability of the first MTC joint. Hypermobility of the first MT head as it moves through its oblique axis from dorsomedial to plantar lateral is believed to contribute to the deformity and is accentuated by the obliquity of the joint. Excessive medial obliquity is associated with instability.

The final bony anatomic considerations involve the sesamoids. The sesamoids are located in the flexor hallucis brevis (FHB) tendon and lie under the first MT head. They have an important weight-bearing function in addition to improving the biomechanical axis of the FHB action. The plantar aspect of the first MT head has a longitudinal intersesamoid ridge in its center termed the crista. The sesamoids lie on either side of this ridge as they articulate with the plantar surface of the first MT head. Normally, they should be centered under the first MT head on the standing anteroposterior radiograph of the foot. As the great toe develops a valgus deformity, the first MT head deviates medially, and rotation occurs at the MTPJ. The great toe pronates, the intrinsic musculature rotates laterally, and the first MT head displaces medially, subluxing off the sesamoids.

Normally, the sesamoids should be centered under the first MT head, and corrective procedures that restore this relationship should be chosen.

Other considerations in assessing the deformity include associated pes planus deformity, pronation of the great toe, and an Achilles tendon (AT) contraction. The AT has a dynamic effect on ambulation. A contracted AT compromises ability to dorsiflex the foot. During gait, the result is external rotation with increased demands placed on the medial structures of the forefoot. The HV deformity is believed to be a result of this repetitive stress. A contracted AT can be idiopathic or a result of a neuromuscular disease. Either should be noted on the physical examination because their presence can contribute to recurrence of deformity if they are not addressed.

In addition to the bony anatomy of the deformity, the soft tissue envelope at the first MTPJ plays a role in the HV deformity. The first MT head has no direct muscle attachments, so its position is influenced greatly by the alignment of the PP. Essentially, 4 groups of muscles and tendons cross the first MTPJ and attach on the proximal aspect of the PP. The balance of these structures and the bony contour of the joint determine whether the PP stays aligned on the MT head. Dorsally, the extensor hallucis longus (EHL) and extensor hallucis brevis (EHB) insert centrally on the distal and proximal phalanges respectively. They are kept in a central position by the hood ligaments, a fibrous band of tissue that is anchored to the collateral ligaments.

On the plantar surface, the flexor hallucis longus (FHL) runs centrally between the sesamoids and inserts on the distal phalanx. The FHB has 2 tendon slips, which insert into the medial and lateral sesamoids. The sesamoids then connect into the PP through the plantar plate. Medially, the abductor hallucis tendon inserts into the plantar medial PP and plantar medial joint capsule. The capsule becomes much thinner dorsally.

A similar relationship exists on the lateral side of the joint with the adductor hallucis tendon inserting onto the lateral sesamoid and plantar lateral joint capsule. The abductor hallucis has 2 muscle bellies, which are the transverse head and the oblique head. These come together in the conjoined tendon and insert on the lateral sesamoid. Comparatively, more muscle mass is present in the adductor hallucis when the muscle bellies are combined, creating a natural tendency to pull the PP into valgus.

These 4 groups of attachments create a delicate balance for keeping the PP centered on the first MT head. This balance is enhanced greatly when the first MT head is relatively flat. When the head is rounded, it is much easier for the PP to deviate. Once a deviation is created, the forces quickly are unbalanced. The insertion of the adductor hallucis onto the lateral plantar base of the PP becomes the primary deforming force as the HV increases. Since its insertion is on the plantar half of the capsule and sesamoid, it tends to pronate the toe. As the rotation occurs, the abductor hallucis becomes more plantar, and the only medial restraint left is the thin dorsal joint capsule, which readily becomes attenuated.

Once an angular deformity exists, the EHL and extensor digitorum brevis (EDB) are no longer centered on the PP and bowstring across the lateral side of the deformity, creating further imbalance. In considering the treatment of HV, one must address both the bony deformity and the soft tissue balance since both contribute to the pathologic condition.

Contraindications: Contraindications to surgery include feet with vascular insufficiency or an active infection.

Osteotomy of either the PP and/or the first MT is used extensively to correct alignment of the first ray. The PP osteotomy (Akin procedure) is a medially based closing wedge osteotomy of the PP (Akin, 1925; Brahms, 1994; Goldberg, 1987; Plattner, 1990). It is combined with medial eminence excision and medial capsulorrhaphy. This procedure is best for deformity in the PP manifesting as HV interphalangeus in which the PPAA is abnormal. Akin osteotomy also may be combined with a first MT osteotomy to compensate alignment created by an elevated DMAA (Mitchell, 1991).

The incision is made just proximal to the medial eminence, and is extended distally to the IPJ. The dissection is taken down to the joint capsule. Once exposed, a vertical capsulotomy is made with not more than 2-4 mm of capsule removed. The medial eminence is next excised in line with the shaft of the first MT and just medial to the sagittal sulcus. Next, the osteotomy of the PP is completed, removing 3-4 mm of bone. Care must be taken at the proximal cut to ensure that the articular surface is not violated. The medial capsule is then repaired first in order to observe the amount of correction that must be completed with the osteotomy. The osteotomy is then fixed with Kirschner wires (K-wires) or suture. Care must be taken to check for correct rotation as the osteotomy is fixed.

Summary of Akin osteotomy is as follows:

• Indications
  • HV interphalangeus
  • Also can be combined with other procedures to compensate for an increased DMAA in a congruent joint
• Expected corrections
  • May correct 10-15° of deformity in PP
  • HVA tends to recur according to long-term follow-up results
  • Has no effect on 1-2 IMA
• Complications
  • Recurrence of deformity
  • Poor cosmetic appearance

First metatarsal osteotomy

The next category of procedure for HV correction is the first MT osteotomy. This can be divided into distal and proximal osteotomies. Distal osteotomies are mainly for individuals with mild deformities (eg, HVA <30º, 1-2 IMA <13º) (Austin, 1981; Johnson, 1991; Johnson, 1979). Some authors have advocated use of this in deformities as large as 15º in the 1-2 IMA. This can work depending on the osteotomy chosen.

Chevron distal metatarsal osteotomy

One of the more commonly used distal osteotomies is the chevron ostectomy (see Picture 6). This osteotomy is performed through a medial incision. An L-shaped capsulotomy is performed to expose the medial eminence. The exostosis is removed with a saw, with a cut parallel to the medial border of the foot. Making the exostectomy cut parallel to the medial border of the foot increases the surface area of contact for the chevron osteotomy. On the other hand, making the cut parallel to the medial metatarsal shaft obviates the danger of removing too much medial eminence. If too much is removed, it can result in loss of support for the proximal phalanx with a resultant varus deformity. Once the medial eminence is resected, an ink marker is used to outline the chevron. The apex is placed in the center of the MT head. The osteotomy is V-shaped; the angle of the chevron may vary. Making one limb longer than the other is advantageous because this simplifies fixation. The author makes theplantar limb longer. Care is taken not to overpenetrate the lateral cortex as this may lead to damage of the lateral soft tissues.

Once the osteotomy is complete, the MT head is translated laterally. This is performed by placing a skin hook or towel clangs on the proximal fragment and then sliding the capital fragment laterally. Sometimes, an osteotome must be inserted along the osteotomy cuts to free the soft tissues enough to allow the lateral translation. Also, when a long plantar limb is used, the soft issue is more likely to impede lateral translation; thus, it is advantageous to gently mobilize the capital fragment using an osteotome. Excessive manipulation should be avoided. It is also important to not let the saw cut extend across the apex because this can create a stress riser in the capital fragment when fracture may occur during manipulation of the MT head. The MT head should be translated 3-5 mm laterally but no more than one third the width of MT shaft. It is then fixed with a single K-wire (0.62), which is inserted from dorsal-proximal to plantar-distal taking care not to violate the MT head sesamoid articulation.

The pin is left in place for 4 weeks and removed in the office. The osteotomy is inherently stable and through metaphyseal bone that heals quickly. Screws and more complex fixation methods are not necessary. Due to the mild risk of sterile abscess, the author chooses to avoid bioabsorbable implants. However, DeOrio and Ware have shown that the use of a single poly-p-dioxanone pin attached to a K-wire can be used routinely for fixation obviating the need for external pin placement. After the osteotomy is fixed, the excess medial cortex of the proximal fragment is resected in line with the MT head. All edges are smoothed with a rasp or rongeur. The capsule can be shortened to gain further correction by resecting the redundant segment from the proximal aspect of the limb of the capsulotomy made parallel to the joint.

Standard compression bunion dressings are used for 7-8 weeks and changed every 1-2 weeks. As stated above, the pin is removed after 4 weeks. The patient should expect to return to full-time footwear in 10-12 weeks. This may vary depending on any additional procedures done to the foot (ie, hammertoe correction, bunionette correction).

Summary of chevron distal MT osteotomy is as follows:

• Indications
  • HVA <30º
  • 1-2 IMA <13º
  • DMAA <15º
• Expected corrections
  • HVA 12-13º
  • 1-2 IMA 4-5º
• Complications
  • Undercorrection when indications are extended to large deformities (Hattrup, 1985; Mann, 1982).
  • Avascular necrosis in 12-20% (increased incidence when adductor release is performed)

Proximal metatarsal osteotomy

Proximal MT osteotomies are used for larger deformities, generally those with an IMA of greater than 15º. These osteotomies usually are combined with a DSTR, which is necessary to correct metatarsophalangeal (MTP) subluxation with an HVA greater 35º. Many types of osteotomy have been described. These include a medial opening wedge, a lateral closing wedge, proximal chevron, and a crescentic (Coughlin, 1997). The wedge osteotomies can change the length of the first MT, and these have not been widely advocated. Additional osteotomies include the Scarf, Ludloff and Mao. Presently, the proximal chevron and crescentic osteotomies are widely used, and, with proper technique, they can achieve excellent correction (Mann, 1992; Sammarco, 1993; Thordarson, 1992; Wanivenhaus, 1988).

The author currently uses a modification of the proximal chevron osteotomy described by Sammarco (Sammarco, 1993). This is combined with a DSTR as previously described. After the distal releases have been performed, the medial incision is extended proximally to the level of the first TMT joint. The periosteum is elevated just enough to expose the medial cortex of the first MT. The osteotomy is designed with the apex pointing proximally with a long plantar limb. The angle of the osteotomy is approximately 70-80º. The osteotomy is performed using a microsagittal saw. Care must be taken not to extend the cuts past the apex of the osteotomy as this may create a stress riser and increase the risk of fracture.

After the osteotomy is completed, the distal fragment is rotated laterally with the osteotome; the upper limb behaves like an opening wedge osteotomy while the lower limb acts as a shelf to prevent elevation or depression of the distal fragment. Once the desired correction is achieved, the osteotomy can easily be fixed using two 2.7-mm cortical lag screws placed dorsal to plantar. The resected medial eminence is morselized and packed into the opening wedge portion of the osteotomy. Two screws provide very stable fixation, and the technique of using an osteotomy with a plantar shelf has been demonstrated to be biomechanically sound.

Similar correction can be obtained using a proximal crescentic osteotomy (Mann, 1992; Thordarson, 1992). This osteotomy is analogous to the focal dome osteotomy used in correction of lower extremity deformity. Its main advantage is that it results in minimal shortening.

The osteotomy is performed through a dorsal incision. Care must be taken to protect the EHL and to avoid injury to the terminal portion of the medial branch of the superficial peroneal nerve, which passes over the first TMT joint. The osteotomy is performed 1-1.5 cm distal to the first TMT joint. The crescentic cut is made perpendicular to the plantar surface of the foot or at a 120º angle to the long axis of the first MT. Some literature supports doing either a concave distal or concave proximal orientation. Either way, care must be taken to avoid overcorrection. The osteotomy is fixed using a cortical lag screw going dorsal, distal to plantar proximal. A K-wire may be added for rotational stability. Achieving rigid stabilization is important to avoid loss of fixation and elevation of the first MT. Rigid fixation may be difficult to obtain especially in osteoporotic bone. The author currently uses the proximal chevron osteotomy because the fixation is easier to obtain and inherently more stable.

The postoperative course is much the same as that of the distal MT osteotomy. Depending on the fixation, a postoperative shoe, fracture walker, or cast may be used. Weightbearing is protected for the first 4 weeks. Generally, most patients do not bear weight much in the first 3-4 weeks due to pain. Once wound healing is ensured, weight bearing progresses. Patients with more proximal procedures have a slightly longer recovery period.

Summary of proximal first MT osteotomy with DSTR is as follows:

• Indications
  • HVA >30°
  • 1-2 IMA >14º
• Expected corrections
  • HVA 23-24º*
  • 1-2 IMA >8-11º (crescentic), 3-6º (closing wedge), 7º (opening wedge)

    (*HV correction is directly proportional to severity of preoperative deformity.)

• Complications
  • Shortening of first ray (closing wedge)
  • Elevation first ray causing transfer lesion to second MT head
  • Undercorrection
  • Overcorrection
  • Delayed union/malunion

Arthrodesis and resection

First tarsometatarsal fusion

The first TMT arthrodesis can be used to obtain correction in moderate to severe categories of HV. Its main use is in the patient with a hypermobile first ray and a moderate to severe deformity (1-2 IMA >15º, HVA >30º) (Klaue, 1994; Maguire, 1973; Mauldin, 1990; Myerson, 1990; Sangeorzan, 1989). The incidence of hypermobile first ray has been debated. Mann and Coughlin have reported a hypermobile first ray is present in fewer than 5% in patients with HV.

TMT arthrodesis also can be used as a salvage operation after a failed bunion repair when there is still an increased 1-2 IMA. Contraindications are juvenile HV with an open epiphysis, short first ray, and MTP degenerative arthritis. The procedure is performed through a dorsal incision extending from the first web space proximally to the TMT joints. The EHL is retracted laterally. The subchondral bone is exposed using a small osteotome to scrape off the cartilage.

In people who truly have a hypermobile first ray, resection of wedges of bone may not be necessary. Often, the 1-2 IMA can be reduced and the joint pinned with wires for provisional reduction. A radiograph is obtained. If the positioning of the first ray is acceptable, it can be fixed after the preparation of the subchondral surface by feathering using an osteotome or with multiple drill holes. The margins of the fusion are bone grafted with local bone obtained from the bunion resection, distal tibia, or calcaneus.

In persons in whom the first TMT cannot be reduced, joint resection is performed with a microsagittal saw removing biplanar wedge based lateral and plantar. This resection must be performed carefully to avoid excessive shortening. Fixation is performed with 3.5-mm cortical screws placed in lag fashion. Cannulated screws may be used in persons in whom wire fixation is performed first to ensure acceptable positioning. The screw configuration used consists of 3 screws. The first goes dorsal distal to plantar proximal. The second goes dorsal proximal to plantar distal crossing the TMTJ. The third goes transversely medial to lateral across the bases of MTs 1 and 2. Care must be taken to maintain compression across the TMTJ.

This procedure is always combined with DSTR as described previously. The postoperative course typically involves a longer recovery than the more distally based procedures. Patients are placed in a standard soft bunion dressing with a plaster splint to immobilize the ankle. At the first dressing change, this is converted to a short leg cast with a soft spica dressing to hold the great toe in place. Touchdown weight bearing is allowed to tolerance. Weight bearing progresses after the first month, and the patient is given a fracture walker with a bunion dressing if radiographs exhibit acceptable signs of healing. The bunion dressing is continued until the 2-month postoperative check. At that point, if radiographs demonstrate fusion, the patient can progress slowly to wearing a firm-soled shoe. Typically, it can take another 6 weeks before patients are comfortably wearing a shoe full time.

Summary of first TMT fusion is as follows:

• Indications
  • HVA >30º
  • 1-2 IMA >15º
  • MTP subluxation and hypermobile first ray
• Expected corrections
  • HVA 18º
  • 1-2 IMV 6-8º
• Complications
  • Nonunion (10-12%)
  • Pain (42%)
  • Dorsiflexion plantar flexion malunion
  • Overcorrection
  • Undercorrection

The final procedures to consider in bunion correction are joint sacrificing procedures. These are arthrodesis of the first MTPJ and resection arthroplasty.

Metatarsophalangeal joint arthrodesis

Arthrodesis of the first MTPJ is used for salvage after failed bunion surgery, bunions associated with osteoarthritis or rheumatoid arthritis, severe HV (HVA >40°, IMA >16°). With modern internal fixation methods high rates of fusion can be achieved (Coughlin, 1994; Coughlin, 1987; Coughlin, 1990; Mann, 1989; Mann, 1980; Turan, 1987).

Many methods for preparing the joint have been described. Resection may be performed with flat surfaces or with reamers that shape the PP and MT head in mirror images. The advantage of this latter technique is that less shortening is achieved and the position of the toe can be adjusted when hemispheric reamers are chosen. The most critical aspect of the arthrodesis is the position of the first toe. Generally, it should be fused in 15º of valgus, 30º of dorsiflexion in relation to the first MT and neutral rotation. The best landmarks are clinical though because the first toe should be positioned adjacent to the second toe and have enough dorsiflexion so the surgeon can place the tip of his finger under the distal phalanx of the toe being fused when this foot is placed in a plantigrade position on a hard flat surface.

Too much dorsiflexion leads to pain at the tip of the toe when the patient wears shoes; too little dorsiflexion can lead to premature arthrosis or instability of the first IPJ. Too much valgus can cause impingement on the second toe and one must anticipate the gradual decrease in the IMA that will occur after an MTP fusion so that impingement does not occur.

The technique currently used by the author for fusion is hemispheric reaming and compression screw fixation. If rigid fixation cannot be obtained with 2 crossed 4.0-mm cancellous screws, a dorsal plate can be added. It has been the author's experience that many dorsal plates become symptomatic and require later removal; thus, if adequate fixation is achieved with compression screws, that is all that is used.

The joint is approached through a dorsal incision. When no previous scars are present, this incision is used, though the arthrodesis also can be accomplished through a previous medical incision if being performed for recurrent HV. Full-thickness flaps are raised sharply off the MT head. The collateral ligaments are elevated and released if necessary to achieve correction. The medial eminence is removed using a rongeur or oscillating saw. The articular cartilage is removed using an osteotome to scrape it off of the subchondral bone. At this point, the cannulated hemispheric reamer is used to ream the surfaces, removing the subchondral bone to expose cancellous surfaces, which are best for achieving fusion. Care must be taken not to remove too much bone. Additionally, when a dorsal approach is used, a tendency may exist to remove too much bone dorsally, leading to excessive dorsiflexion. This can be avoided by increased exposure and plantar flexion of the PP during the reaming.

Once the joint is prepared, the surfaces are opposed in the desired position and pinned with a K-wire. The author uses an intraoperative fluoroscanner to check position of the fusion and hardware. Cannulated screws are used when wire placement is in the desired position. Two screws are used going from medial/distal to proximal lateral and medial/proximal to distal lateral crossing at the joint. The screw threads should engage the far cortex and provide rigid fixation. In severely osteoporotic bone, a plate may be used. A low profile plate is best chosen with 2.7-mm screws. In this case, only one screw crosses the joint and the plate is applied dorsally with 2-3 screws proximal and distal.

Postoperatively, bulky gauze compression dressing and a surgical shoe are used. When fixation is tenuous, a cast or fracture walker may be used for additional immobilization. Patients are allowed to bear weight once wound healing is ensured, usually after 2-3 weeks. After 6 weeks, if fusion is evident on radiographs, patients are allowed to start bearing weight in a firm-soled shoe. Most patients have returned to full time footwear use by 10-12 weeks postoperatively.

Summary of MTPJ arthrodesis is as follows:

• Indications
  • HV with arthrosis rheumatoid arthritis
  • Neuromuscular conditions (spasticity)
  • Recurrent valgus (HVA >40°)
• Complications
  • Nonunion (generally <10% with internal fixation techniques)
  • Malunion (too little valgus, increase IPJ arthrosis)
  • Excessive plantar flexion (pressure at tip of toe and increase IPJ arthrosis)
  • Excessive dorsiflexion (intractable plantar keratosis first MTH pain at tip of toe or nail dorsally)
  • Painful hardware
  • Infection

Excisional arthroplasty (Keller-Privdere)

Resection arthroplasty is rarely used for correction of HV. It should be used for moderate deformity with coincident arthrosis in patients who are elderly with low demands (Richardson, 1990; Vallier, 1991; Wrighton, 1972). The procedure can accomplish mild correction, decompresses the MTPJ, and heals quickly. It does result in shortening of the toe, loss of push off power, and, in cases when excessive resection is performed, may result in a cock-up deformity due to loss of the plantar attachment of the FHB. It should be used mainly as a salvage procedure in low-demand patients.

The procedure can be performed through either a dorsal or medial incision. A medial incision is preferred because it allows medial capsular plication to accomplish correction of alignment. The capsule is elevated from distal to proximal leaving the proximal, with the proximal attachment remaining. It is tagged with a resorbable suture. The medial eminence is excised. The base of the PP is exposed. Care must be taken to preserve the plantar capsule. The cut is made at the metaphyseal flare. Excessive resection leads to shortening and increases the chances of a cock-up deformity; thus, only the proximal 25% of the phalanx should be excised. After excision, the capsule is repaired to the remaining phalanx through drill holes. Repairing the plantar capsule is essential to minimize the risk of postoperative cock-up deformity. Medial capsular repair corrects the vagus deformity. The joint is then pinned with 2 crossed .062-in K-wires, which are removed 3-5 weeks postoperatively.

A standard soft gauze postoperative bunion dressing is used and the patient is allowed limited weight bearing in a postoperative shoe. Walking should be restricted to avoid the complication of pin breakage.

Summary of excisional arthroplasty (Keller-Privdere) is as follows:

• Indication - Moderate HV in a low-demand patient with osteoarthrosis of the MTPJ
• Expected corrections
  • HVA correction up to 50%, best results when HVA <30º
  • IMA minimal correction
• Complications
  • MT due to loss of weight-bearing function of great toe (Results tend to deteriorate with time.)
  • Cock-up deformity
  • Shortening
  • Flail toe
  • Diminished push off strength

Preoperative details: It is worth repeating, that it is critical to obtain high quality standing x-rays in the AP and lateral direction prior to proceeding with surgery.