Bunion Treatment & Management

Nonoperative treatment should be the initial option discussed. The first aspect of HV treatment is for patients to wear properly fitting shoes. The forefoot should be no more than 0.5 cm wider than the toe box of the shoe. Women who wear shoes narrower than this have a higher incidence of forefoot complaints.^{[3, 4]} When compared to other women in the general population in the same age group, according to Thordarson and colleagues,^[19] women about to undergo bunion surgery reported significant increased body pain, decreased foot and ankle function, and decreased shoe comfort.

Foot problems are also very common in the elderly population. Using a questionnaire and clinical assessment, Menz and Morris^[20] evaluated 176 patients aged 62 to 96 years with foot pain and deformity. They found that most of the patients wore shoes narrower than their feet and that women, in proportion to their feet, wore shoes that were shorter, were narrower, and had a smaller total area than those worn by men. This was associated with corns on the toes, HV deformity, and foot pain.

Orthoses have been shown to be more effective at reducing pain at 6 months of treatment, but at 12 months, no difference is noted compared with the control of no treatment. They also are not effective at increasing the ability to work at 1 year. Chevron osteotomy is superior to orthotic treatment.^[21]

Shoe modifications, such as bubble stretching, can ease the pressure over a bony prominence. Orthotic inserts seem to be of limited help in treatment of HV, but custom orthotics can be of great assistance if the symptoms are caused mainly by a transfer lesion. A good orthotic prescription should include medial posting to control pronation (which increases valgus forces on the hallux), an MT pad for transfer lesions, extra shoe depth with an oblique toe box, and possibly a bunion flare, which goes behind the bunion deformity to alleviate pressure from the shoe.^[22] Some nonprescription devices also can provide symptomatic relief, although none have been demonstrated to achieve lasting correction.

A multitude of procedures are available to correct the deformity, although the results of surgery can be quite variable if the deformity is not addressed directly.^[23] The table below divides HV deformities into mild, moderate, and severe. These categories are used extensively in order to simplify choosing the best procedure, although they are probably best used to choose a category of procedure rather than a specific procedure.

Table. Categories of Hallux Valgus Deformity (Open Table in a new window)

Surgical options fall into several broad categories, as follows: distal soft-tissue reconstruction (DSTR), PP and first MT (distal and proximal) osteotomies, arthrodesis (MTPJ and first tarsometatarsal [TMT]), and resection.

A mild HV deformity can be corrected with a DSTR.^[24] This consists of medial eminence excision and medial capsulorraphy. On the lateral side, the deforming structures must be released to balance the toe, a procedure that typically is performed through a dorsal longitudinal incision in the first webspace. The conjoined tendon is released from the lateral sesamoid. The transverse MT ligament is released from its attachment on the lateral sesamoid as well. The lateral joint capsule is divided parallel to the joint surface. The proximal portion of the released adductor tendon may be sutured to the proximal joint capsule of the MTPJ, or the capsule may be sutured to the medial capsule of the second MTPJ.

This soft-tissue procedure is considered an intra-articular realignment. It must be performed only in persons with a round MT head and a relatively normal DMAA and PPAA. This procedure realigns the toe, provided that the bony anatomy accepts this realignment. In reality, the DSTR is seldom used alone, usually being combined with a bony procedure.

DSTR can be summarized as follows:

• Indications

  • Mild to moderate bunion deformity
  • HVA less than 35°
  • IMA less than 15°
  • Nonelevated DMAA
  • Noncongruent joint
• Expected corrections

  • HVA 14°
  • IMA 5°
• Complications

  • Hallux varus - Usually asymptomatic if less than 10°; the incidence is significantly lowered by not excising the lateral sesamoid
  • Recurrence of deformity - Occurs when the procedure is extended to larger deformities or when the bony alignment is not favorable (eg, elevated DMAA)
• Results: After correction of HV deformities with a DSTR and a proximal crescentic osteotomy, first-ray mobility in cadaver specimens was significantly reduced (with several studies having demonstrated that patients with HV deformities have increased first-ray sagittal mobility).^[25]

Osteotomy of the PP, the first MT, or both 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.^{[26, 27, 28, 29]} 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. The Akin osteotomy may also be combined with a first MT osteotomy to compensate alignment created by an elevated DMAA (see image below).^{[30, 31]}

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 then 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, and 3-4 mm of bone is removed. 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 subsequently fixed with Kirschner (K) wires or suture. Care must be taken to check for correct rotation as the osteotomy is fixed.

Akin osteotomy can be summarized 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
• Results: Used alone, the Akin osteotomy should be reserved for deformity in the proximal phalanx. Basile and colleagues^[32] compared the distal first-MT Chevron-Akin osteotomy to the DSTR-Akin osteotomy, for correction of mild hallux valgus. The investigators noted a statistically significant outcome in which the distal first-MT Chevron-modified Akin double osteotomy resulted in a greater correction of the intermetatarsal 1-2 angle, HVA, and tibial sesamoid position than that accomplished with the DSTR-modified Akin 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 < 30°, 1-2 IMA < 13°).^{[33, 34, 35]} Some authors have advocated the use of these in deformities as large as 15° in the 1-2 IMA. Distal MT osteotomies performed through a percutaneous approach have been used in Europe but have not been widely accepted in the United States. Statistically significant improvements in the postoperative mean HV angle, first IM angle, DMMA, and sesamoid position were observed, using the percutaneous method. A shorter operating time and reduced risks of complications were noted as well.^{[36, 37]}

Mitchell's osteotomy is another means of distal correction; it involves a double cut through the MT neck, leaving a step in the lateral cortex to hitch onto the MT head. The capital fragment is displaced laterally and plantarward and then is held in place with a stitch through drill holes.^{[38, 39]} A Japanese study found that this procedure can produce MTP malalignment, metatarsalgia, and plantar callosity after surgery. According to the report, combining a modified Mitchell's osteotomy with an oblique MT osteotomy of the lesser MT bones significantly improved callosity and metatarsalgia and the use of commercially available shoes at 5-year follow-up.^[40]

Chevron distal metatarsal osteotomy

One of the more commonly used distal osteotomies is the chevron osteotomy (see image below).^{[41, 42]}

This procedure is performed through a medial incision. An L-shaped capsulotomy is carried out to expose the medial eminence. The exostosis is removed with a saw, using a cut parallel to the medial border of the foot. Making the exostectomy cut parallel to the medial border 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 medial eminence is removed, it can result in loss of support for the PP, with a resultant varus deformity.

Once the medial eminence is resected, an ink marker is used to outline the chevron, the apex of which 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 the plantar limb longer. Care is taken not to overpenetrate the lateral cortex, as this may lead to damage of the lateral soft tissues. The chevron osteotomy angle was investigated at 60° versus 90° with longer plantar limb, by cohort and finite element analysis (FEA). The FEA demonstrated that there were more compressive forces and less shear stresses at the osteotomy site with a 90° cut, which is more conducive to bone formation, with at least similar results between the cohorts.^[43]

Once the osteotomy is complete, the MT head is translated laterally; a skin hook or towel clamps are placed on the proximal fragment, and then the capital fragment is translated 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, gently mobilizing the capital fragment with an osteotome is advantageous.

Excessive manipulation should be avoided. It also is 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 the MT shaft. It is then fixed with a single K-wire (0.62), which is inserted from dorsal-proximal to plantar-distal. Care must be taken to avoid violating the MT head–sesamoid articulation.^[44]

The pin is left in place for 3-5 weeks and removed in the office. The osteotomy is inherently stable and is through metaphyseal bone, which heals quickly. Screws and more complex fixation methods are not necessary. Because of the mild risk of sterile abscess, the author chooses to avoid bioabsorbable implants. However, DeOrio and Ware^[45] have shown that 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. One concern with distal osteotomies is the risk of avascular necrosis. Kuhn and colleagues^[46] have shown that blood flow to the head of the MT decreases by 71% over baseline recordings, with the largest drop coming after capsulotomy (45%). The total blood flow goes up to 58% after lateral release and adductor tenotomy, then to a 71% decrease from baseline when the osteotomy is added. This explains why avascular necrosis (AVN) is one of the possible complications of this surgery. However, clinically significant AVN requiring treatment is actually quite rare.

Standard compression bunion dressings are used for 7-8 weeks and changed every 1-2 weeks. 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 performed on the foot (eg, hammertoe correction, bunionette correction).

Chevron distal MT osteotomy can be summarized as follows:

• Indications

  • HVA less than 30°
  • 1-2 IMA less than 13°
  • DMAA less than 15°
• Expected corrections

  • HVA 12-13°
  • 1-2 IMA 4-5°
• Complications

  • Undercorrection when indications are extended to large deformities^{[14, 47]}
  • AVN in 12-20% (theoretically, there is an increased risk when adductor release is performed, but this has not been observed in clinical series)
• Results: In a comparison study after 2 and 5 years of follow-up, the chevron osteotomy was found to be a reliable procedure for the correction of mild and moderate hallux valgus deformity, and outcome did not differ on the basis of age.^{[48, 49]}

Proximal metatarsal osteotomy

Proximal MT osteotomies are used for larger deformities, generally those with an IMA of greater than 15°.^{[50, 51]} These osteotomies usually are combined with a DSTR, which is necessary to correct MTP subluxation with an HVA of greater than 35°. Many types of osteotomy have been described, including medial opening-wedge, lateral closing-wedge, proximal chevron, and crescentic osteotomies.^[11] The wedge osteotomies, which can change the length of the first MT, have not been widely advocated. Additional osteotomies include the Scarf,^{[52, 53, 54]} Ludloff,^[55] and Mao^{[56, 57]} types. Presently, the proximal chevron and crescentic osteotomies are widely used, and with proper technique, they can achieve excellent correction.^{[58, 59, 60, 61]}

When comparing the Ludloff and chevron osteotomies, the Ludloff has been reported to have better correction of the IMA but results in greater shortening of the first ray.^[62]

The proximal chevron osteotomy is described by Sammarco and colleagues (see image below).^[59] This is combined with a DSTR. After the distal releases have been performed, the medial incision is extended proximally to the level of the first TMT joint (TMTJ).

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 70-80°. 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, and 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 a pair of 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.^{[58, 60]} This procedure is analogous to the focal dome osteotomy used in the correction of lower-extremity deformity. The main advantage of the proximal crescentic osteotomy is that it results in minimal shortening. Although proximal chevron osteotomy and proximal crescentic osteotomy were similar at reducing the HAA, the chevron osteotomy was better at reducing healing time and was associated with a lower incidence of dorsiflexion malunion.^[63]

The proximal crescentic 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 TMTJ. The osteotomy is performed 1-1.5 cm distal to the first TMTJ. The crescentic cut is made perpendicular to the plantar surface of the foot or at a 120° angle to the long axis of the first MT. Some literature supports either a concave distal or concave proximal cut orientation. Either way, care must be taken to avoid overcorrection.

Three-dimensional computer analysis has shown that the osteotomy started distal to the TMTJ and angled at 22° toward the proximal sesamoid articulation allows for a longer osteotomy and, therefore, less shortening and MT-head elevation. Adding a 10° plantarward coronal tilt also can help limit MT-head elevation.^[64] The osteotomy is fixed using a cortical lag screw going dorsal, distal to plantar proximal. Two K-wires may be added to provide a significantly more stable fixation, providing a viable option to the limited methods of additional fixation. Achieving rigid stabilization is an important means of avoiding loss of fixation and elevation of the first MT. Jung and colleagues^[65] have shown that when screw purchase is poor with the second screw, the use of 2 K-wires can provide fixation without a significant loss of strength. Rigid fixation may be difficult to obtain, especially in osteoporotic bone.

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. An immobilization orthosis is an option that makes walking possible on postoperative day 1 by supporting the first MT and shifting weight to the other MT shafts. This orthosis could be an effective solution for patients who, for whatever reason, need to walk right away or for patients having bilateral hallux valgus correction.^[66] Weightbearing is protected for the first 4 weeks. Generally, most patients do not bear weight much in the first 3-4 weeks, because of pain. Once wound healing is ensured, weightbearing progresses. Patients with more proximal procedures have a slightly longer recovery period.

Proximal first-MT osteotomy with DSTR can be summarized as follows:

• Indications

  • HVA greater than 30°
  • 1-2 IMA greater than 14°
• Expected outcome

  • HVA 23-24° - HV correction is directly proportional to the severity of the preoperative deformity.
  • 1-2 IMA greater than 8-11° (crescentic), 3-6° (closing wedge), 7° (opening wedge)
• Complications

  • Shortening of first ray (closing wedge)
  • Elevation of first ray, causing transfer lesion to the second MT head. Crescentic osteotomies, however, have been shown to have variable pressure patterns under the second MT head. This was thought to result from the overall geometric design of the crescenteric osteotomy, which is well suited for rotation in the horizontal plane but is inherently unstable in the sagittal plane.^[67]
  • Undercorrection
  • Overcorrection
  • Stiffness of first MTPJ
  • Delayed union or malunion
• Results: A study by Jones and colleagues^[68] showed that total range of motion and dorsiflexion were significantly decreased postoperatively when compared to their preoperative range of motion (P < .005). The magnitude of correction showed no correlation to the change (P < .005). This immediate decrease in motion underscores the importance of joint mobilization early in recovery to prevent long-term loss of mobilization. A 1- and 3-year follow-up study showed that patients with first-MT pain and metatarsalgia at 1 year postoperatively were also more likely to experience pain and metatarsalgia at 3 years. The same study showed that in 87% of patients, radiologic changes were minimal or nonexistent between 1 and 3 years, providing evidence that a patient's 1-year follow-up clinical status is predictive of long-term outcome.^[69]

First-tarsometatarsal fusion

The first-TMT arthrodesis can be used to correct moderate-to-severe HV. Its main use is in the patient with a hypermobile first ray and a moderate-to-severe deformity (1-2 IMA >15°, HVA >30°).^{[70, 47, 71, 72, 73]} The incidence of hypermobile first ray has been debated. Mann and Coughlin have reported that a hypermobile first ray is present in fewer than 5% of patients with HV.^[10]

TMT arthrodesis can also be used as a salvage operation after a failed bunion repair, when there is still an increased 1-2 IMA. In a prospective observational cohort study of patients who presented with a recurrent HV deformity after undergoing surgery between May 1996 and August 1999, Coetzee and colleagues^[74] showed that first-TMT arthrodesis is a dependable and successful option for revision after failure of surgical treatment of HV. 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 webspace proximally to the TMTJs. 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,^[75] 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 laterally and plantarward. 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 consists of 3 screws: the first goes dorsal distal to plantar proximal; the second goes dorsal proximal to plantar distal, crossing the TMTJ; and the third goes transversely medial to lateral across the base of MTs 1 and 2. Care must be taken to maintain compression across the TMTJ.

This procedure is always combined with DSTR. The postoperative course typically involves a longer recovery period than procedures that are more distal. 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. Patients are kept nonweightbearing for the first month and are then allowed to engage in touchdown weightbearing for balance in the second month. 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.

When this procedure was used in conjunction with a bunionectomy and distal soft-tissue realignment (Lapidus procedure),^{[76, 77]} according to Kopp and colleagues,^[78] good clinical results were achieved, with significant improvements in pain, activity, limitations, and footwear requirements. Radiographically, the investigators also reported significant improvements in the IM and HV angles, with an average correction of 8-10° and 10-15°, respectively.

First-TMT fusion can be summarized as follows:

• Indications

  • HVA greater than 30°
  • 1-2 IMA greater than 15°
  • MTP subluxation and hypermobile first ray
• Expected corrections

  • HVA 18°
  • 1-2 IMV 6-8°
• Complications

  • Nonunion (10-12%)
  • Pain (42%)
  • Dorsiflexion plantar flexion malunion
  • Overcorrection
  • Undercorrection
  • Painful hardware
• Results: In a clinical follow-up study using radiologic and pedobarographic examinations in 56 patients with arthrodesis of the first TMTJ, bony consolidation occurred at 9 weeks postoperatively. The average first IM angle improved from 20.4° to 11.2°, and the American Orthopaedic Foot and Ankle Society (AOFAS) score significantly improved, from 51 to 92 points at 8.2 months postoperatively.^[79]

The final procedures to consider in bunion correction are joint-sacrificing surgeries. 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, for bunions associated with osteoarthritis or rheumatoid arthritis, and for severe HV (HVA >40°, IMA >16°). With modern internal fixation methods, high rates of fusion can be achieved.^{[80, 81, 82, 83, 84, 85]} Results of first-MTPJ arthrodesis as a treatment for severe hallux valgus deformities resulted in a high percentage (>85%) of successful results at an average follow-up of over 8 years, with a significant reduction in postoperative pain.^[86] Also, the IMA will correct without the addition of a basal osteotomy in patients undergoing MTPJ arthrodesis.^[87]

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 10-15° of valgus and 30° 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 for the surgeon to be able to place the tip of his or her 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; one must anticipate the gradual decrease in the IMA that will occur after an MTP fusion, so that late impingement does not occur.

The technique currently used by the author for fusion is hemispheric reaming and compression screw fixation. Currently, the author uses a 2.7-mm lag screw with a one-quarter tubular plate. This provides very stable fixation, allowing early weightbearing. The head of the 2.7-mm screws is very shallow, so hardware prominence has not been problematic. When no previous scars are present, the joint is approached through a dorsal incision, although the arthrodesis can also be accomplished through a previous medial incision if it is 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 expose 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 fluoroscan to check position of the fusion and hardware. A low-profile plate is best chosen, with 2.7-mm screws. In this case, only one screw crosses the joint, using a lag technique. 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 8-10 weeks postoperatively.

MTPJ arthrodesis can be summarized as follows:

• Indications

  • HV with arthrosis and/or rheumatoid arthritis
  • Neuromuscular conditions (spasticity)
  • Recurrent valgus (HVA >40°)
  • Fixed hallux valgus deformity
• Complications

  • Nonunion (generally < 10% with internal fixation techniques)
  • Malunion (too little valgus, increased IPJ arthrosis)
  • Excessive plantar flexion (pressure at the tip of the toe and increased IPJ arthrosis)
  • Excessive dorsiflexion (intractable plantar keratosis in the first metatarsal head, pain at the tip of the toe or nail, dorsally)
  • Painful hardware
  • Infection
• Results: Coughlin and associates^[86] produced a report that evaluated the results of first-MTPJ arthrodesis as treatment for severe and moderate HV deformities. Using data derived over a 22-year period in a single surgeon's practice, the investigators showed that arthrodesis of the first MTPJ for idiopathic HV resulted in a high percentage of successful results, at an average follow-up of over 8 years. In addition to a significant reduction in postoperative pain (P < .001), the postoperative AOFAS scores averaged 84 (range 72-90), and there was complete resolution of lateral metatarsalgia at final follow-up.

When compared with the Hohmann osteotomy in patients with first-ray hypermobility, the Lapidus procedure (arthrodesis) was equally effective at reducing pain at 2 years and equal at correcting the HVA (N=101, 50 Homan, 51 Lapidus).^[88]

Excisional arthroplasty (Keller)

Resection arthroplasty is rarely used for correction of HV. It should be employed for moderate deformity with coincident arthrosis, in patients who are elderly and have low demands.^{[89, 90, 91, 92]} The procedure, which can accomplish mild correction, decompresses the MTPJ and allows quick healing. However, it does result in shortening of the toe and loss of push-off power; in cases when excessive resection is performed, it may produce a cock-up deformity resulting from loss of the plantar attachment of the FHB.

Compared with a distal osteotomy, a Keller arthroplasty is less effective at improving the IMA and range of motion at 3-year follow-up.^[93] However, the Keller arthroplasty is better than arthrodesis at retaining mobility at 2 years, although there was no demonstratable difference in pain or dissatisfaction.^[94] The Keller arthroplasty should be used mainly as a salvage procedure in patients with low physical demands.

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 attachment. 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, not more than 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 because it minimizes the risk of postoperative cock-up deformity. Medial capsular repair corrects the valgus deformity. The joint is then pinned with 2 crossed, 0.062-inch K-wires, which are removed 3-5 weeks postoperatively.

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

Excisional arthroplasty (Keller) can be summarized as follows:

• Indication - Moderate HV in a low-demand patient with osteoarthrosis of the MTPJ
• Expected corrections

  • HVA correction up to 50%; best results are achieved when the HVA is less than 30°
  • IMA minimal correction
• Complications

  • Metatarsalgia resulting from the loss of weightbearing function of the great toe. (Results tend to deteriorate with time.)
  • Cock-up deformity
  • Shortening
  • Flail toe
  • Diminished push-off strength
• Results: In a long-term retrospective analysis of an uncontrolled series of basal metatarsal closing-wedge osteotomies and Keller excision arthroplasties, performed in patients aged 14-40 years, statistical analysis revealed significantly better clinical and radiologic outcomes after osteotomy. In fact, it was recommended that Keller arthroplasty be abandoned for the treatment of HV in young and active patients.^[95]

More recently, techniques have been developed in attempts to decrease soft tissue injury (primarily), decrease healing time and morbidity, and improve cosmesis. The 3 categories of techniques include percutaneous, minimally invasive, and arthroscopic procedures. Currently, the majority of articles published on minimally invasive, percutaneous, and arthroscopic techniques are of low-quality, level IV evidence.^[96] Only a handful of prospective comparative trials have been performed.

Percutaneous forefoot surgery

Percutaneous forefoot surgery (PFS) is typically performed with a 1- to 3-mm incision using a miniblade and power rotary burr by way of tactile sensation and intraoperative image intensification.^[97]

A 2-year prospective study was performed on the percutaneous Reverdin-Isham osteotomy and included 104 cases.^[1] For the procedure, a 3- to 5-mm plantar-medial incision is created over the metatarsal head. Capsule detachment and resection of the medial and dorsal protrusions of the MTP head are performed with a low-speed conical burr under fluoroscopic guidance. This is followed by the actual Reverdin-Isham osteotomy created by a straight burr with the same medial approach, conserving the lateral cortex. A lateral capsule and ligamentous release is then performed via a second 3-mm incision medial to the EHL using a Beaver blade. In addition to this, a varisation osteotomy of the first phalanx is performed via a dorsal approach medial to the EHL with a straight burr, again preserving the lateral cortex.

Complete weight bearing was resumed immediately in a rigid postoperative shoe. Several complications included 4 first metatarsal and 5 first proximal phalanx lateral cortex fractures, 6 DMAA hypercorrection of less than 0°, 2 subjects with painful severe joint rigidity, 2 with complex regional pain syndrome, 3 with recurrence of deformity, and 2 with transfer metatarsalgia after 18 months. The results of functional outcomes via AOFAS were comparable to other studies of percutaneous or standard open hallux valgus procedures such as chevron osteotomy or Scarf.

This procedure does seem to fall short on reliably reducing the DMAA.^{[1, 98]} Bauer et al therefore concluded this procedure be restricted to medium-to-moderate HV correction without significant metatarsus varus (IMA ≤15°).^[1] It also is a difficult procedure to perform with a long learning curve. A few studies have shown higher complication rates with the percutaneous distal metatarsal osteotomy for HV, including a high rate of recurrence of HV and dorsal malunion.^[99]

A technique of distal percutaneous metatarsal osteotomy has been described. A 2-mm-diameter K-wire is inserted extraperiosteally from the medial corner of the nail of the great toe along the medial side of the hallux. A 3- to 5-mm incision is made down to bone at the metatarsal neck, and the periosteum around the osteotomy site is detached. The osteotomy is made through the subcapital region of the first metatarsal under fluoroscopy in the sagittal plane, perpendicular to the long axis of the shaft of the first metatarsal, but with slight mediolateral obliquity in the frontal plane. The K-wire is then driven down the central axis of the metatarsal through the osteotomy. Patients are allowed to bear weight in a firm-soled postoperative shoe on the first postoperative day. This procedure is for mild-to-moderate HV with a first intermetatarsal angle of 10-20°.^[36]

Minimally invasive techniques

Minimally invasive surgery is performed via a 1- to 2-cm incision with a traditional blade and power saw under direct visualization, possibly with fluoroscopic guidance.^[97] The SERI (simple, effective, rapid, inexpensive) technique is similar to the percutaneous method described above, except it is performed through a slightly larger incision under direct visualization and the osteotomy is made via an oscillating saw.

The SERI technique is indicated to correct mild-to-moderate reducible deformity when the HV ankle is less than or equal to 40° and the IMA is less than or equal to 20, with only mild arthritis. Contraindications include age older than 75 years, severe arthritis or stiffness of the MTPJ, and severe instability of the cuneometatarsal joint and MTPJ.^[100] Mixed studies exist regarding the results, and the procedure may require a significant learning curve in order to achieve acceptable results.^{[99, 100]}

Another described minimally invasive surgical technique is the Bösch osteotomy. This was compared with the open Scarf osteotomy in a comparative retrospective study with 36 subjects in each group.^[101] The procedure is indicated for HVA of 20-40°, IMA up to 20°, and a DMAA up to 25°, with no radiographic evidence of degenerative MTP arthritis. The Bösch osteotomy is performed via a medial approach, approximately 2-cm incision, and osteotomy customized to correct the patient’s individual deformities. The head is freed with an osteotome, and the osteotomy is fixed with 2 K-wires. Immediate heel walking was allowed for both groups. There was decreased operating room time for the minimally invasive Bösch procedure, shorter hospital stay, and equivalent AOFAS and FAOS scores at 2-year follow-up.^[101]

The Bösch osteotomy was also compared with the open Kramer technique. The minimally invasive Bösch approach did allow earlier discharge; however, it had a trend toward a higher complication rate (was not statistically significant, but may have been underpowered) and had lower patient satisfaction with a trend toward more shortening compared with the open Kramer procedure.^[102]

Arthroscopic techniques

Proposed advantages of arthroscopic procedures, in addition to the advantages of other lesser invasive techniques, include improved assessment of sesamoid reduction and minimization of overcorrection.^[13] An arthroscopic Lapidus procedure has been described.^[103] This was a limited study on 5 patients with 1 year of follow-up. The procedure included an arthroscopic Lapidus as well as a minimally invasive chevron osteotomy distally on patients with severe HV (>16°) and hypermobility of the first MCP. The procedure involves a percutaneous release of the lateral joint capsule and adductor tendon, followed by insertion of 3 portals, medial to tibialis anterior, superior between the tibialis anterior and EHL, and lateral between the EHL and the deep peroneal neurovascular bundle.

The working space is created just around the joint capsule. The joint cartilage is removed with a Beaver blade, followed by limited abrasion of subchondral bone with a bone resector to prevent shortening. Then, several holes are drilled into the subchondral bone. An intermetatarsal screw is inserted between the first and second metatarsals to correct the IM angle. Fixation of the joint is achieved with 2 percutaneously placed screws. Next, the minimally invasive chevron osteotomy is performed to correct the HV angle.

Of the 5 patients, no complications were reported, and all returned to preoperative activities within 4 months. One-year postoperative AOFAS scores improved an average of 51 points to a range of 87-90. Radiographic evaluation confirmed fusion in all patients by 4 months, with an average HV angle improvement of 26° and IM angle improvement of 11°. Functional results are similar to other reported outcomes with open Lapidus,^{[104, 78]} and radiographic results were at least equivalent.^{[105, 104, 71]}

An arthroscopic technique with proposed advantages of allowing an improved view of the articular surface allows for more-controlled resection of only the cartilage, and no subchondral bone, to limit shortening and promote bone healing, in addition to minimizing soft tissue damage and offering a better cosmetic result. The author noted that it is a more technically demanding, requiring a skilled arthroscopist.^[103]

While there are several less invasive techniques starting to be performed and early results have been published, larger comparative trials are needed to provide the proof of the additional proposed benefits without increased failure and morbidity.

It is worth repeating that it is critical to obtain high-quality standing radiographs in the AP and lateral direction prior to surgery.

A liposomal form of the local anesthetic bupivacaine (Exparel) was approved by the US Food and Drug Administration (FDA) in October 2011. A single dose infiltrated into the surgical site produces postsurgical analgesia for bunionectomy. The recommended dose for bunionectomy is 93 mg (7 mL) infiltrated into tissues surrounding the osteotomy and the remaining 13.3 mg (1 mL) into the subcutaneous tissue.

In 2 randomized, placebo-controlled studies, Apfelbaum et al found that the COX-2 inhibitor, parecoxib (investigational in the United States), along with supplemental analgesia provided as needed, was effective for pain relief over 1-3 days in patients who underwent bunionectomy, although this is not approved for use in the United States.^[106]

For patient education resources, see the Foot, Ankle, Knee, and Hip Center, as well as Chronic Pain.

Recurrence is the most common complication following bunionectomy, particularly in cases in which the deformity and soft tissues at the first MTPJ are undercorrected. For additional complications related to specific surgical procedures, see Treatment, Surgical therapy.

In a 2-year follow-up study evaluating the effect of 3 different types of HV surgeries, Thordarson and colleagues^[107] reported that patients who had HV surgery had significant improvements in 4 of their short form (SF)–36 scores, in 4 out of 5 American Academy of Orthopaedic Surgeons (AAOS) lower-extremity scores, and in 4 out of 5 AOFAS scores. The degree of deformity, amount of correction, and type of operation did not influence outcome.

When treatment addresses each component of the deformity, satisfactory results are possible. However, patients must have realistic expectations. Recurrent deformity, HV, and stiffness are the most common complications. Even with good corrections, some limitations still exist in 30% of patients.

The HV deformity is complex, as it often involves multiple levels of the first ray. Successful treatment requires careful definition of the deformity. Probably the most common reason for recurrence and less-than-optimal results is failure to carefully define the deformity. If the deformity is not carefully defined, the surgical procedure chosen may not address all components of the deformity. Recurrence or less-than-optimal results also occur when the procedure is used at the upper limits of its indications. When each component of the deformity is addressed, satisfactory results can be achieved.