Hallux Valgus Osteotomy 

Hallux valgus is a deformity at the base of the big toe, or metatarsophalangeal (MTP) joint, in which the great toe (hallux) is deviated or points toward the lesser toes; in severe types of the deformity, the great toe goes over or under the second toe.

The head of the first metatarsal does not have any musculotendinous attachments. These structures in the great toe bypass the head of the first metatarsal to be inserted into base of the proximal and distal phalanges. When the great toe is in a normal alignment, the tendons and muscle forces exerted around the head and at the first MTP joint are balanced. When there is a malalignment at this joint muscle imbalance gradually worsens the deformity.

Long-standing hallux valgus deformity is associated with a contracture in the overpowering lateral musculotendinous structures and stretching of the medial joint capsule. As the deformity increases, the first metatarsal head becomes prominent medially, giving rise to the bunion deformity.

A number of operative procedures and osteotomies have been devised and or modified over the years. The great variety of procedures and osteotomies underscores the points that not all hallux valgus deformities are similar and that no single osteotomy is versatile enough to treat all such deformities. Therefore, selection of the exact procedure(s) to be employed for operative intervention must be based on careful clinical and radiologic evaluation and planning.

Decision-making requires careful consideration of the following:

• History - Patient age; duration and severity and location of pain; involvement of other joints; response to conservative care; activity level; occupation; expectations
• Comorbid conditions - Diabetes mellitus; rheumatoid arthritis; gout; stroke; any other underlying spastic neurologic conditions
• Physical findings - Severity of deformity; presence of bursitis, cellulitis, calluses, rotational deformity, or pronation; passive reducibility of the hallux valgus subluxation or the bunion deformity; hypermobility of the metatarsocuneiform (MTC) and other joints; pes planus; gastrocnemius contracture; neurovascular status
• Diagnostic imaging - Radiographic evaluation of the hallux valgus; intermetatarsal (IM), interphalangeal (IP), and distal metatarsal articular angles; MTP joint congruity; sesamoid-metatarsal head subluxation; MTC joint congruity or arthrosis; relative lengths of the metatarsals and the parabola at MTP joints 1-5

Failure of conservative care in relieving symptoms due to hallux valgus deformity is an indication for consideration of surgical intervention. Some patients worry that the deformity may become worse and therefore prefer it to be corrected earlier rather than later.

However, rapid progression of a hallux valgus deformity is unusual; therefore, the deformity can be observed and the decision regarding surgery based mainly on symptoms. Pain and discomfort and failure of conservative measures to relieve symptoms and meet lifestyle needs should be the major considerations for surgical correction.

Patients should realize that return to professional or recreational activities (eg, sports or dancing) cannot be guaranteed. They must understand that some residual stiffness, pain, or deformity may be inevitable. After surgery, they may or may not be able to return to their previous level of activity. Therefore, surgery is deferred unless the bunion deformity is interfering with their activities. If patients can eventually resume their previous level of activity after surgery, they will be much more satisfied with the outcome.[1]

At present, reputable societies such as the American Orthopedic Foot and Ankle Society (AOFAS) advise against cosmesis as an indication for surgery. Surgery should not be performed just to enable patients to wear fashionable shoes. Patients who have bunion surgery only because they believe that they will then be able to wear a more fashionable shoe are subsequently disappointed if they are still not able to wear the shoes they wanted to wear or if the surgery leaves them with a stiff toe or with pain.

In reviewing more than 300 bunion cases, Coughlin and Jones observed that a third of patients could wear the shoes that they wanted before surgery and that two thirds could after surgery. Unfortunately, this still leaves one third of patients unable to wear their shoes of choice, and this should be explained to those patients who do not have pain but simply want to fit their feet into narrower shoes.[2, 3]

Patients with poor vascularity are at risk for wound-healing problems and gangrene with loss of toes. Other contraindications include advanced arthrosis of the MTP joint, gout, neuropathy, spasticity of any type (eg, cerebral palsy, cerebrovascular accident [CVA], or head injury), and ligamentous laxity.

Anatomy

The metatarsal bones are roughly cylindrical in form, with the body tapering gradually from the proximal to the distal end. They are curved in the long axis and present a concave plantar surface and a convex dorsal surface.

The first metatarsal is the stoutest and the shortest of the metatarsal bones. The body is strong and of well-marked prismoid form. The base usually has no articular facets on its sides, but occasionally there is an oval facet on the lateral side, by which the first metatarsal articulates with the second metatarsal.

The proximal articular surface of the first metatarsal is large and kidney-shaped; its circumference is grooved (for the tarsometatarsal [TMT] ligaments) and medially gives insertion to part of the tendon of the tibialis anterior; its plantar angle presents a rough, oval prominence for the insertion of the tendon of the fibularis (peroneus) longus. The head is large; on its plantar surface are two grooved facets, on which glide sesamoid bones; the facets are separated by a smooth elevation.

For more information about the relevant anatomy, see Foot Bone Anatomy.

Complication prevention

It is essential to remain constantly aware of the anatomy and location of the neurovascular structures. Careful dissection and retraction of the flaps before execution of the osteotomy is important to prevent soft-tissue damage. Also, thermal damage should be avoided by using a low setting on the driver for the saw, performing irrigation, employing a sharp thin blade with fine teeth, and taking care to unclog the teeth if the same saw is being used.

Jeuken et al published a level II randomized control trial that provided long-term follow-up data on the results of two widely used operative treatments for hallux valgus: scarf osteotomy (36 feet) and chevron osteotomy (37 feet).[4] Conventional weightbearing anteroposterior (AP) radiographs of the foot were obtained for evaluation of the IM angle (IMA) and hallux valgus angle (HVA) and for clinical evaluation. The AOFAS rating system for the hallux MTP-IP scale was used, together with physical examination of the foot. These data were compared with the results from the original study.

The Short Form 36 (SF-36) questionnaire, the Manchester-Oxford Foot Questionnaire (MOXFQ), and a general questionnaire including a visual analogue scale (VAS) pain score were used for subjective evaluation.[4] The primary outcome measures were the radiologic recurrence of hallux valgus and the reoperation rate of the same toe. Secondary outcome measures were the results from the radiographs and subjective and clinical evaluation.

At 14 years' follow-up, the response rate was 76%.[4] In all, 28 of the 37 feet in the chevron group and 27 of the 36 in the scarf group developed recurrence of hallux valgus. One patient in the scarf group had a reoperation of the same toe, compared with none in the chevron group. Current VAS pain scores and results from the SF-36, MOXFQ, and AOFAS did not significantly differ between groups.The authors concluded that the two techniques yielded similar results after 2 years of follow-up. At 14 years' follow-up, neither technique was superior in preventing recurrence.

Wester et al conducted a prospective randomized study to assess radiologic and clinical results after operation for severe hallux valgus, comparing open wedge osteotomy with crescentic osteotomy.[5] The study included 45 patients (41 female, 4 male) with severe hallux valgus (HVA >35º and IMA >15º). Mean patient age was 52 years (range, 19-71 years). Treatment involved either proximal open wedge osteotomy and fixation with plate (group 1) or operation with proximal crescentic osteotomy and fixation with a 3-mm cannulated screw (group 2). Clinical and radiologic follow-ups were performed 4 and 12 months after the operation.

In group 1, the HVA decreased from 39.0º to 24.1º after 4 months and to 27.9º after 12 months.[5] In group 2, it decreased from 38.3º to 21.4º after 4 months and to 27.0º after 12 months. The IMA in group 1 was 19.0º preoperatively, 11.6º after 4 months, and 12.6º after 12 months. In group 2, the mean IMA was 18.9º preoperatively, 12.0º after 4 months, and 12.6º after 12 months. After 12 months, the AOFAS score improved from 59.3 to 81.5 in group 1 and from 61.8 to 84.8 in group 2. The ratios of the length of the first metatarsal to that of the second were 0.88 and 0.87 preoperatively and 0.88 and 0.86 after 12 months for groups 1 and 2, respectively.

The authors concluded that both procedures improved AOFAS and VAS scores in patients operated on for severe hallux valgus.[5] No significant difference was found between the two groups with respect to postoperative improvement of hallux valgus and IMA at 4 and 12 months postoperatively. Postoperative VAS and AOFAS scores were comparable for the two groups, with no significant differences. An expected tendency to gain better length of the first metatarsal with open wedge osteotomy than with crescentic osteotomy was not found. Even though the reductions in IMA and HVA were only suboptimal, the improvement in AOFAS score was comparable to that seen in other similar clinical trials.

Minimally invasive approaches are increasingly being used for hallux valgus surgery. In a prospective, randomized study of 50 patients undergoing operative correction of hallux valgus, Lee et al compared percutaneous chevron/Akin (PECA) osteotomy (n = 25) with open scarf/Akin (SA) osteotomy (n = 25).[6] Data were collected preoperatively and at 1 day, 2 weeks, 6 weeks, and 6 months postoperatively. Outcome measures included the AOFAS hallux-MTP-IP (AOFAS-HMI) score, the VAS score, the HVA, and the 1-2 IMA.

Both groups showed significantly improved AOFAS-HMI scores after surgery (PECA, from 61.8 to 88.9; SA, from 57.3 to 84.1), with comparable final scores.[6] HVA and IMA were also similar at final follow-up. However, the PECA group had a significantly lower pain level in the early postoperative phase (postoperative day 1 to postoperative week 6). No serious complications were observed in either group. The two groups had comparable good-to-excellent clinical and radiologic outcomes at final follow-up. 

Choi et al investigated the efficiency of simultaneous correction of moderate-to-severe hallux valgus deformity and adult-type pes planus in 19 consecutive patients (15 [79%] women, 4 [11%] men; mean age, 44.50 ± 17.13 years; mean follow-up, 31.30 ± 17.02 months).[7] Medial calcaneal sliding osteotomy was performed to correct hindfoot valgus, whereas treatment of hallux valgus was case-dependent.

Postoperatively, mean HVA was 8.40º ± 5.29º, mean IMA was 4.20º ± 2.54º, mean hindfoot alignment angle was 3.09º ± 2.92º, and mean hindfoot alignment ratio was 0.41 ± 0.17.[7] Although there was one case of hallux varus deformity occurring as a postoperative complication, there were no cases of postoperative recurrence. The authors found simultaneous correction of hallux valgus and pes planovalgus with a medial calcaneal sliding osteotomy to be effective technique in reducing recurrence of hallux valgus and increasing satisfaction in patients with moderate-to-severe hallux valgus deformity complicated with adult-type pes planus accompanying hindfoot valgus.

McDonald et al prospectively studied 60 patients undergoing right first metatarsal osteotomy for hallux valgus correction surgery with the aim of determining when patients could safely return to driving after the procedure.[8]  Testing of patients' brake reaction time (BRT) was performed at 6 weeks and repeated until patients achieved a passing BRT. A control group comprising 20 healthy patients was used to establish a passing BRT. Patients were given a novel driver readiness survey to complete.

At 6 weeks, 51 of the 60 patients (85%) had BRTs of less than 0.85 seconds and were considered safe to drive.[8] At 6 weeks, the passing group average was 0.64 seconds. At 8 weeks, 59 (100%) of the patients who completed the study achieved a passing BRT. Patients who had a failing score at 6 weeks had statistically higher VAS pain scores, as well as diminished range of motion (ROM) in the first MTP joint.

On the driver readiness survey, eight (89%) of the nine patients who did not pass disagreed or strongly disagreed with the statement "Based on what I think my braking reaction time is, I think that I am ready to drive."[8]  The authors concluded that most patients can safely return to driving 8 weeks after right metatarsal osteotomy for hallux valgus correction; some patients may be eligible to return to driving sooner, depending on VAS score, first MTP ROM, and driver readiness survey results.

Panchbhavi et al measured reduction of the forefoot width in 52 patients after hallux valgus correction with a distal Chevron osteotomy and Akin osteotomy.[9] A new measurement, the metatarsal span (MS), was introduced as a measure of forefoot width. On pre- and postoperative radiographs, four observers measured the HVA, the first and second IMAs, and the MS. Preoperative HVA ranged from 14° to 48°, IMA ranged from 6° to 25°, and MS ranged from 74.2 to 110.6 mm. Average HVA improvement was 19.4°, average IMA improvement was 6.7°, and average MS reduction was 8.7 mm. No correlation was identified with regard to correction of the HVA or IMA to MS.

Panchbhavi and Lindeman conducted a retrospective analysis (N = 30; 33 feet) to determine the average and maximum corrections achievable with the chevron-Akin double osteotomy.[10]  HVA and IMA were evaluated pre- and postoperatively on standard weightbearing AP plain radiographs, and the differences from preoperative to postoperative were calculated. Patients were divided into three groups according to the severity of preoperative hallux valgus (mild [3 feet], moderate [19 feet], and severe [11 feet]). The pre-to-post changes in HVA and IMA and the postoperative values of each angle were compared between severity groups, and the rate of correction to normal was noted in each severity group.

In the mild group, average improvement was 13 in HVA and 6 in IMA; maximum correction was 14 in HVA and 9 in IMA; and three feet (100%) were corrected to the normal range.[10] In the moderate group, average improvement was 16.5 in HVA and 5.2 in IMA; maximum correction was 29 in HVA and 9 in IMA; and 18 feet (95%) were corrected to the normal range. In the severe group, average improvement was 28.5 in HVA and 8.8 in IMA; maximum correction was 43 in HVA and 20 in IMA; and nine feet (82%) were corrected to the normal range. These results suggested that the combined chevron-Akin double osteotomy is capable of both small and large degrees of angular correction in hallux valgus.

The patient should be educated on selection of proper footwear. Size is an important criterion. Because feet swell at the end of the day, shoe shopping is best done in the evening. A useful aid in determining an appropriate size is to draw the outline of the foot on tracing paper and then to ensure that the insert of the shoe covers the tracing completely.

Traditionally, a tourniquet is applied at the level of the thigh. Over the years, however, it has been found that tourniquets applied more distally in the leg just above the ankle work just as well and decrease the area that is unnecessarily exsanguinated, thereby limiting the reperfusion injury or effects. In addition, a more distal tourniquet need not be inflated to the same high pressure; typically, 250 mm Hg or 100 mm Hg higher than the systolic blood pressure is sufficient.

Anesthesia

Hallux valgus corrective procedures can be undertaken with a local anesthetic block around the base of the first metatarsal and in the first web space or with an ankle block if other toes will also be undergoing surgical intervention. A calf- or ankle-level tourniquet can be uncomfortable, and if such a tourniquet is required, a popliteal level block is also a suitable alternative. The block can be supplemented by sedation; alternatively, the procedure can be undertaken with laryngeal mask or endotracheal anesthesia, depending on the preferences of the patient and the anesthesiologist.

Regardless of whether the patient receives a general anesthetic or not, the author highly recommends preemptive analgesia and anesthetic techniques that are multimodal and give excellent preoperative anesthesia and postoperative pain control, which is an important objective (especially for prevention of chronic pain).

On the day of surgery, if no contraindications exist, a cyclooxygenase (COX)-2 inhibitor is given in the morning. The author has a motto ("needle before knife") and believes in injecting a mixture of short-acting and long-acting local anesthetic before making the skin incision in an effort to preemptively block noxious stimuli during surgery. Postoperatively, oral analgesics are started before the local anesthetic effect wears off and continued at the prescribed intervals for 2-3 days. With this regimen, patients can potentially go through the entire experience with little or no pain.

Positioning

Patient is positioned supine with pressure points padded. The author uses a triangular support under the knee, which helps keep the foot flat on the table and makes orientation easier to follow.[11] The foot is elevated over a bump of double-brick height and shape to clear it from the other limb, allowing unobstructed ease of access for the use of instruments (eg, the saw or drill) and fluoroscopy. The knee support also stabilizes the limb and lessens the need or reliance on assistance for maintaining position of the limb or the foot.

The patient is instructed to keep the dressings clean and dry and the leg elevated to minimize postoperative edema or swelling in the foot. Active exercises of the knee and hip are encouraged.

The first clinic visit after surgery should take place between postoperative days 7 and 10, at which time the wound is checked and dressings changed. The dressings are reapplied in a manner similar to their original placement, and either an accommodative shoe or a cast is applied for protection for the next 4-5 weeks. The patient is allowed to bear weight on the heel.

At 6 weeks, all dressings are taken down. Kirschner wires (K-wires), if used, are removed, and a weightbearing radiograph is obtained. Exercises of the great toe can begin, and the patient is allowed return to activities and full weightbearing as tolerated.

Osteotomies for hallux valgus are performed via a medial approach. A longitudinal incision along the midline at the junction of plantar and dorsal skin on the medial border of the foot straddling the metatarsophalangeal (MTP) joint is marked and made with a No. 15 blade. Careful dissection is carried out in the loose areolar tissue plane that is naturally there, created by movement of skin and subcutaneous tissue over the capsular structures. Dissection in this plane is safer and easier and creates full-thickness soft-tissue flaps superficial to the level of the joint capsule.

The dorsal and plantar flaps thus created carry the dorsomedial and plantar-medial digital nerves and are kept retracted and away from instruments for rest of the procedure. Then, the capsule is incised along the line of incision, exposing the medial eminence. The proximal and distal extension of the exposure depends on the exposure needed and the type of osteotomy planned. The bunion prominence on the medial aspect of the head of the metatarsal is excised in line with the medial aspect of the foot. Excessive resection can lead to hallux varus.

Generally, the more severe the deformity is, the more proximal or longer the osteotomy on the first metatarsal will have to be, and the more likely it is that more than one level will have to be involved (eg, an additional osteotomy in the proximal phalanx). Selection of a particular osteotomy is also dependent on the surgeon's familiarity and experience with the various surgical options.

For mild deformities, a distal metatarsal osteotomy, such as a chevron osteotomy, is sufficient. For moderate and severe deformities, a midshaft or proximal osteotomy along with a phalangeal osteotomy may be necessary. The midshaft osteotomies commonly performed are the scarf osteotomy (or Z osteotomy) and the Ludloff osteotomy. A closing or opening wedge osteotomy at the base of the metatarsal or the cuneiform is also an option for severe deformities. Commonly performed osteotomies are described further below.

A chevron osteotomy, as the name indicates, is chevron-shaped and is located in the broad metaphyseal region at junction of head and neck. A 0.062-in. drill hole is useful to mark the apex of the chevron on the metatarsal head. The drill hole is started on the medial surface of the head at or just proximal to the center of an imaginary sphere that is the head of the metatarsal and driven in a direction that is medial to lateral and in a line that is parallel to the plantar surface and the articular surface of the head of the metatarsal (see the images below).

Chevron osteotomy to correct severe hallux valgus deformity: deformity on left side and on right side operated previously.

Chevron osteotomy to correct severe hallux valgus deformity: preoperative anteroposterior radiograph with patient standing.

Chevron osteotomy to correct severe hallux valgus deformity: preoperative anteroposterior radiograph with measurements of hallux valgus angle and intermetatarsal angle.

The limbs of the chevron consist of two cuts made by a sagittal saw, starting at the hole. These cuts extend proximally at a 60º angle, with the plantar cut exiting the plantar cortex proximal to the sesamoid articulation.

As the osteotomy is performed, irrigation is carried out to dissipate heat. As the saw blade approaches the lateral cortex, care must be taken not to overpenetrate the cortex and enter the lateral soft tissues, so that the blood supply to the metatarsal head is not damaged. Badwey et al reported that the capital fragment can be displaced laterally up to 6 mm in males and 5 mm in females; this amounts to displacement of approximately 30% of the metatarsal's width.[12]

To displace the osteotomy, it is sometimes useful to hold the proximal portion of the metatarsal with a small towel clip while pushing the metatarsal head laterally. The osteotomy is then fixed with a single Kirschner wire (K-wire). The author uses the K-wire as a buttress (see the images below).[13]

Chevron osteotomy to correct severe hallux valgus deformity: intraoperative radiograph of anteroposterior and oblique views showing K-wire being used as "buttress."

Chevron osteotomy to correct severe hallux valgus deformity: intraoperative radiograph of lateral views showing chevron-shaped osteotomy cut and K-wire.

The tip of the wire is held flat against the displaced head and first brought out distally through a long soft-tissue sleeve; the proximal tip of the wire is then cut blunt. With the displacement held, the blunt tip is introduced into the shaft of the proximal fragment and advanced proximally by tapping on its distal end until the blunt end lodges securely in the subchondral region at the base of the metatarsal. The excess sharp projection at the displaced distal medial end of the shaft of the first metatarsal is trimmed (see the images below).

Chevron osteotomy to correct severe hallux valgus deformity: foot in follow-up period at 6 weeks and tip of K-wire on medial side of great toe.

Chevron osteotomy to correct severe hallux valgus deformity: anteroposterior radiograph showing correction of deformity and improvement in hallux valgus angle and intermetatarsal angle.

Chevron osteotomy to correct severe hallux valgus deformity: lateral radiograph showing healed chevron osteotomy.

Chevron osteotomy to correct severe hallux valgus deformity: great toe in improved alignment as compared with preoperative photograph.

Three-point fixation across the chevron osteotomy with a K-wire can be used as an alternative for stabilization of the osteotomy (see the images below).

Chevron osteotomy with three-point fixation: preoperative anteroposterior radiograph shows hallux valgus deformity.

Chevron osteotomy with three-point fixation: intraoperative radiograph shows use of Kirschner wire (K-wire) engaging three cortices: lateral and medial cortices of proximal fragment in shaft of first metatarsal and third cortex in lateral aspect of head of metatarsal. This kind of fixation gives more rigid fixation than K-wire engaging only two cortices across osteotomy.

Chevron osteotomy with three-point fixation: radiograph shows healing of chevron and Akin osteotomy at final follow-up with correction of hallux valgus deformity.

Chevron osteotomy with three-point fixation: photograph of patient at final follow-up shows correction of deformity and great toe in neutral rotation.

A scarf osteotomy is an osteotomy with an outline that resembles the letter Z; for this reason, it is also referred to as a Z osteotomy.

The metatarsal shaft is essentially split into dorsal and plantar halves. This longitudinal split extends into the metaphysis distally into the head and proximally in the base, but it stops 1-2 cm short of the articular surfaces. Transversely directed cuts from medial to lateral in the dorsal half distally and the plantar half proximally create two segments of the first metatarsal, with the plantar half carrying the head segment and the dorsal half carrying the base. (See the images below.)

Osteotomy to correct severe hallux valgus deformity: hallux valgus deformity in left foot.

Scarf osteotomy to correct severe hallux valgus deformity: preoperative anteroposterior radiograph with measurements of hallux valgus angle and intermetatarsal angle.

The exposure described for the chevron osteotomy is used but is extended proximally to expose the medial surface of the first metatarsal. (See the image below.)

Scarf osteotomy to correct severe hallux valgus deformity: exposure for scarf osteotomy on medial aspect of foot.

After the resection of the medial eminence, the osteotomy to be executed is drawn out. A 0.045-in. K-wire is drilled 1 cm away from the articular surface of the head, halfway between the dorsal and plantar surface in a medial-to-lateral direction and also aimed in about a 15º plantar and proximal orientation. Another wire is drilled parallel to this wire—again, halfway between the dorsal and plantar surfaces under fluoroscopy to ensure that it is at least 1 cm distal from the articular surface at the base (see the image below).

Scarf osteotomy to correct severe hallux valgus deformity: fluoroscopic image and needle used to determine proximal extent for osteotomy.

These wires form the apices of the Z and limit the cut that is along the long axis of the shaft. A sagittal saw is used to execute the longitudinal cut, again with the saw blade directed plantarward from medial to lateral (see the images below).

Scarf osteotomy to correct severe hallux valgus deformity: vertical cut and saw blades in horizontal cuts at either end of first metatarsal.

Scarf osteotomy to correct severe hallux valgus deformity: vertical cut and saw blades in the horizontal cuts at either end of the first metatarsal parallel to each other.

At either end of this longitudinal cut, another cut is made along the width, directed from medial to lateral and angled proximally. The distal cut is made dorsal and the proximal cut plantar to the K-wires in this location; additionally, care is taken not to enter the joint at base of the metatarsal. After the osteotomy is conducted, the plantar capital fragment is displaced laterally and the dorsal basal fragment displaced medially to reduce the intermetatarsal (IM) angle (IMA); additionally, the capital fragment can be rotated out to correct articular set angle by taking appropriate-sized medial-based wedges at either end.

Once the deformity is reduced satisfactorily, as determined clinically and radiologically, the displacement is secured with bone clamps and later with two cortical screws 2.5 mm in diameter (see the images below).

Scarf osteotomy to correct severe hallux valgus deformity: fluoroscopic image of displacement held with clamp.

Scarf osteotomy to correct severe hallux valgus deformity: intraoperative photograph of corrected hallux valgus deformity.

Scarf osteotomy to correct severe hallux valgus deformity: anteroposterior radiograph showing correction of deformity and improvements in hallux valgus angle and intermetatarsal angle measured at 3 months.

Scarf osteotomy to correct severe hallux valgus deformity: lateral radiograph showing healed scarf osteotomy and 2 screws used to stabilize osteotomy.

Scarf osteotomy to correct severe hallux valgus deformity: great toe in improved alignment as compared with preoperative photograph.

A Ludloff osteotomy is an oblique osteotomy that begins dorsally a few millimeters distal to the joint at the base of the first metatarsal and is directed plantarward at a 30º angle; it is carried out into the shaft region and stopped just before it exits the plantar surface. A 3.5-mm screw is placed proximally at right angles to the osteotomy; before it is countersunk, the rest of the osteotomy is completed. The capital fragment is then rotated with the screw as an axis to reduce the hallux valgus deformity.

After the desired correction is obtained and checked clinically and radiologically, the screw is tightened, and an additional screw is inserted distal to the first screw to secure the displacement.

An Akin osteotomy is a medial-based closing wedge osteotomy that is performed at the base of the proximal phalanx. It is important to retract the flexor hallucis tendon and the extensor tendon dorsally and to use fluoroscopy to ensure that the proximal articular surface is not violated.

The first cut is made from medial to lateral across the width and is parallel to the base of the proximal phalanx, stopping short of the lateral cortex. The second cut starts just distal to this cut and is aimed to meet the first cut on the lateral cortex, again leaving it weakened but not cut. The wedge-shaped wafer of bone between these two cuts is removed.

The lateral opening is then closed with the weakened lateral cortex as a hinge. The osteotomy is secured with a K-wire that is driven from the plantar medial corner at the base of the proximal phalanx across the osteotomy into the dorsal distal shaft, just enough to engage it.

Although this procedure has commonly been referred to as distal soft-tissue release, first web space soft-tissue release is a more appropriate name for it, both because no "proximal" soft tissues can be released and because the latter term defines the operation more aptly. First web space soft-tissue release is performed to release the contracted lateral structures so that a subluxated head of the metatarsal can be relocated in the joint (see the image below).

First web space release as adjunctive procedure to correct severe hallux valgus deformity: hallux valgus deformity in left foot.

This procedure, as described here, employs a newer technique and a newer approach that is sequential and hidden in the web fold and that is therefore more cosmetic than a dorsal approach, which yields a visible scar on top of the foot.[14]

With the toes held apart, a vertical incision from dorsal to ventral is made in the first web space in such a way as to include the transverse fold of skin (see the image below).

First web space release as adjunctive procedure to correct severe hallux valgus deformity: incision marked out for approach that is hidden in first web space.

Blunt dissection is carried out proximally in the web space to identify the structures while the plantar digital neurovascular bundle is retracted plantarward with a Langenbeck retractor. The soft-tissue structures are identified and then cut in the following sequence:

• Step 1 - The superficial and deep IM ligaments are cut with tenotomy scissors
• Step 2 - The adductor tendon just proximal to its insertion is outlined and detached at its attachment to the fibular sesamoid (see the first image below)
• Step 3 - The capsule is incised longitudinally at the level of the MTP joint with a No. 11 blade
• Step 4 (physical examination) - The reduction of the deformity and the range of motion (ROM) of the first MTP joint are checked; the forefoot is held squeezed with one hand while the other hand assesses ROM at the first MTP joint; if ROM is restored at this stage with the release of the soft-tissue structures mentioned in steps 1-3, the next step is not undertaken, but if ROM is still limited, the lateral sesamoid metatarsal ligament is released as described in step 5
• Step 5 - The contracted lateral sesamoid metatarsal ligament is cut with scissors, with one blade of the scissor inside the capsule and the other outside just dorsal to the fibular sesamoid (see the second image below)
• Step 6 - Two 2-0 polyglactin sutures are placed in the capsule of the first and second metatarsals and the detached stump of the adductor tendon; an assistant holds the forefoot squeezed while the two sutures are tied to bring together the heads of the first and second metatarsals

First web space release as adjunctive procedure to correct severe hallux valgus deformity: deeper tissues exposed, delineating adductor tendon.

First web space release as adjunctive procedure to correct severe hallux valgus deformity: capsule incised longitudinally and head of metatarsal exposed after release of sesamometatarsal ligament.

The wound is irrigated and closed with a subcuticular polyglactin suture either at this stage or after any concomitant procedures planned (eg, scarf osteotomy of the first metatarsal) have been performed.

Panchbhavi et al carried out a retrospective chart review of 76 patients (88 procedures) and a functional outcome analysis of 38 patients (44 procedures) who underwent first web space release with the aforementioned technique.[15] The mean follow-up period was 3.8 years; the mean age was 50.8 years (range, 24-74 years); and 98% of the patients were female.

Most of the patients (89%) had good or excellent results.[15] The surgical scar was hidden between the first and second toes in the web fold. The average Olerud-Molander score was 86.4 out of 100. None of the patients reviewed had nerve injury, recurrence of deformity, hallux varus, or revision surgery. The authors concluded that first web space soft-tissue release is a reliable technique that can be used as an adjunctive surgical procedure in correction of hallux valgus. Because the incision is in the web fold, the resulting scar is hidden.

The correction leaves the capsule on the medial surface of the head redundant. The plantar capsular flap is folded into a V-shaped fold, which is raised in the plantar capsular flap. Enough is folded to take up the slack, and it is excised. This leaves a straight vertical cut, which is then repaired by placing an absorbable suture. The dorsal flap is drawn under the plantar flap and sutured in a pants-over-vest manner with mattress sutures. The rest of the wound is closed with a continuous nonabsorbable subcuticular stitch.

A nonadherent dressing is applied next to the wound and then covered with 4- × 4-in. gauze pieces. A 2-in. gauze roll is then rolled in a figure-eight manner so as to include the base of the big toe and forefoot. A soft roll of cotton is then applied in a similar manner. The aim of the dressing is to ensure that the great toe is held aligned.

A well-padded posterior splint can then be applied for pain relief and protection. Alternatively, a postoperative accommodative shoe with a rocker sole can be used in a reliable patient.

Complications related to iatrogenic or inadvertent injury caused during exposure or execution of the osteotomy and wound closure include the following:

• The digital nerves, especially the branch of the superficial peroneal nerve supplying the dorsomedial part of the big toe, are at risk for injury
• The tendons, especially the flexor hallucis longus tendon, are at risk during execution of an Akin osteotomy
• The blood vessels can be damaged by overpenetration of the saw blade during an osteotomy in the head and neck region or during capsular or soft-tissue release in the first web space
• The head of the first metatarsal may fracture if the apex of a chevron osteotomy is too close to the articular surface
• The deformity may be under- or overcorrected

Complications related to the immediate postoperative period include the following:

• Wound infection may develop, presenting as redness and increased local pain with discharge from the incision site
• Wound dehiscence (separation of the wound edges) may occur with or without infection
• Pin-site infection may occur in association with hardware left prominent outside the skin for ease of removal

Long-term complications include the following:

• Avascular necrosis (AVN) of the head of the metatarsal can occur if the blood supply has been damaged
• The first MTP joint at the base of the big toe can become stiff
• The first metatarsal may end up reduced in length, either structurally (if a wafer of bone is removed or the osteotomy is sloped proximally) or functionally (if the osteotomy site heals with elevation of the head); this may create a biomechanical shift in load sharing away from the first metatarsal head onto the second and other lesser metatarsals, causing a condition known as transfer metatarsalgia
• The hallux valgus deformity may relapse as the musculotendinous structures contract in length over time relative to skeletal length, causing the first ray to buckle at the first MTP joint
• Hallux varus deformity can occur, especially if the medial prominence on the head is excessively resected, the capital fragment is displaced too laterally, or excessive lateral soft-tissue release is performed