Metatarsal lengthening

Brachymetatarsia: A Classification for Surgical Treatment

Brachymetatarsia is a congenital osseous and soft tissue deformity of a ray(s) of the foot. Because there is no particular consensus of methodology of lengthening for brachymetatarsia, the authors introduce a comprehensive anatomic classification and a surgical guide to treatment of each classification type. This classification combines the number of the metatarsal(s) affected and the letter(s) indicating the type of brachymetatarsia deformity (A = axial deficiency of the metatarsal, B = bowing of the metatarsal, C = congruency of metatarsal phalangeal joint). This study reviewed of 300 brachymetatarsals in 166 patients. Fifty of the 166 (30%) patients had bilateral brachymetatarsia. Of the 300 metatarsals with brachymetatarsia, 64 (21%) were first metatarsals, 22 (7%) were second metatarsals, 28 (9%) were third metatarsals, 12 (4%) were fifth metatarsals, and 174 (58%) were fourth metatarsals. Classification types that were found was a total of 165 (55%) type A, a total of 6 (2%) type B, a total of 72 (24%) type AB, a total of 39 (13%) type AC, and a total of 18 (6%) type ABC. A total of 16 (10%) male and 150 (90%) female patients were evaluated. The mean preoperative amount of shortening of the metatarsal was 15 mm (range, 4-20 mm), as determined by the preoperative metatarsal parabola deficiency, equating to 30% of the preoperative metatarsal length. Brachymetatarsia is a complex congenital deformity which until now has not been critically analyzed. This study outlines a comprehensive brachymetatarsia classification system which provides an accurate diagnosis of the deformity and offers a surgical treatment algorithm.

Metatarsal Gradual Lengthening for Brachymetatarsia Using a Mini-rail External Fixator System

Aim

To describe the surgical technique for gradual lengthening of the metatarsal using the Orthofix MiniRail System (Orthofix Medical Inc., Lewisville, TX, USA).

Background

Brachymetatarsia refers to the shortening of the metatarsal bone. When indicated, metatarsal lengthening is performed to treat this deformity.

Technique

A dorsal approach to the short metatarsal is performed, protecting the neurovascular structures and the extensor tendons. The most proximal wire or screw is inserted first, followed by the most distal wire or screw. The distal wire or screw should not be inserted in the metatarsal head. The middle wires or screws are inserted thereafter. All wires or screws should be placed perpendicular to the anatomic axis of the bone. Once the MiniRail lengthener is assembled, a 1.6 mm K-wire is inserted from the tip of the toe into the metatarsal head, blocking the motion of the metatarsophalangeal joint and avoiding joint subluxation during lengthening. The osteotomy is then performed perpendicular to the metatarsal shaft, in between the middle two wires and screws.

Conclusion

The surgical technique for gradual lengthening of the metatarsal using the Orthofix MiniRail System was described in detail with accompanying step-by-step intraoperative clinical and fluoroscopic images.

Clinical significance

This surgical technique of metatarsal lengthening is simple and effective. An understanding of the surgical technique of gradual lengthening of the metatarsal bone is important when treating shorting deformities of more than 1 cm.

How to cite this article

Marwan Y, Abu Dalu K, Bernstein M, et al. Metatarsal Gradual Lengthening for Brachymetatarsia Using a Mini-rail External Fixator System. Strategies Trauma Limb Reconstr 2022;17(3):184-188.

The Surgical Treatment of Brachymetatarsia

This article describes the 3 main surgical options for correction of congenital brachymetatarsia in childhood. The one-stage lengthening by lengthening osteotomy and lengthening with graft interposition are suitable for defects less than 10 mm. For the greater defects from 10 mm to more than 20 mm, gradual lengthening by callus distraction with an external or internal fixator is appropriate. Over the last years, callus distraction with an internal minifixator became commonly established because of the significantly improved aftercare with early full weight-bearing and high postoperative comfort for the child. All 3 surgical procedures are presented with comprehensive image material.

Plantar approach for treatment of brachymetatarsia: A novel approach with an aesthetic consideration

In the past, open osteotomy was always performed through a dorsal approach in the surgical treatment of brachymetatarsia, which created scar formation on the dorsal skin, subsequently resulting in dissatisfaction with cosmetic results. In this study, we provided a plantar approach to avoid forming scars on the dorsal side. A retrospective review was conducted in nine patients (13 feet) with brachymetatarsia treated with an open osteotomy and gradual bone lengthening through a plantar approach. Visual analogue scale (VAS) was used to evaluate the satisfaction of foot appearance, and we designed a questionnaire called appearance index (AI) to assess the influence of foot appearance on quality of life after surgery. The complications were also recorded during the follow-up. The patients were followed up for 34.8 ± 23.7 months. All cases were healed with a time of 64.4 ± 7.1 days and a healing index of 44.1 ± 7.8 d/cm. Satisfaction VAS for foot appearance improved from a preoperative score of 1.7 ± 1.3 points to a postoperative score of 9.3 ± 0.5 points. The AI improved from a preoperative score of 9.2 ± 0.8 points to a postoperative score of 0.6 ± 0.7 points. Complications were observed in three feet (23.1%), but none was related to the plantar approach. In conclusion, the plantar approach for metatarsal osteotomy and pins fixation was a safe and efficient technique with a satisfactory cosmetic result for the patients. No complications related to the novel approach, such as neurovascular injury, were reported.

Aetiology, diagnosis, and treatment of brachymetatarsia: a narrative review

Brachymetatarsia (BM), or hypoplastic metatarsal, is an abnormal shortening of one or more metatarsal bones with a female-to-male ratio of 10.53:1. Different causes are described in the literature, such as congenital, acquired, or iatrogenic, associated with different conditions and syndromes. Its presence may develop deformity and pain; however, often feet are pain free and the major worries of patients are cosmetics. Non-operative treatments aim to improve the comfort of metatarsal heads and the possible dorsal conflict through comfortable shoes or the use of specific orthotics. The surgical treatment is anything but straightforward, with "one-stage" or "two stage" techniques, the latter better called "by gradual distraction". One-stage procedures are more rapid techniques but have limited ability to restore the desired length due to neurovascular compromise caused by acute lengthening. Insufficient correction is also possible. On the contrary, by gradual distraction procedures allow gradual distraction lengthening of more than 1.5 cm, but require the use of an external fixator, with a higher risk of complications in more than about 50% of surgeries. The adjacent metatarsal shortening should be considered in combination with other techniques, to diminish the excessive lengthening. In each case, surgeries should be always decided on each patient's concerns, deformities, and clinical needs.

Brachymetacarpia and brachymetatarsia: do we need to operate?

Brachymetacarpia and brachymetatarsia are rare congenital presentations denoted by shortening of metacarpals and metatarsals respectively, in which the deformity usually presents around childhood/early adolescence.

The aetiology is usually congenital besides several other syndromic or endocrinologic associations.

Cosmetic issues such as absence of a normal-looking knuckle while making a fist or disruption of finger-tip curvature besides functional issues are the main indications for surgical intervention in brachymetacarpia.

In the foot, apart from cosmetic issues, pain due to transfer metatarsalgia as well as callosities along with toe deformities which lead to difficulty of using footwear are the main indications for intervention.

Lengthening of the affected bone, either acute with grafting or gradual, is the mainstay of treatment. Gradual lengthening can be either single-stage as in callotasis, or two-stage where the primary procedure is followed by bone grafting after the length has been achieved.

Adolescence, specifically between 12 and 15 years, is the preferred period for surgical intervention in these cases.

Cite this article: EFORT Open Rev 2021;6:15-23. DOI: 10.1302/2058-5241.6.200087

Callus distraction with external fixator for the treatment of congenital brachymetatarsia of the fourth ray

BACKGROUND

Brachymetatarsia is a rare abnormality of the foot which occurs most frequently in the first and fourth metatarsals. The aim of this study was to evaluate the efficacy of gradual metatarsal lengthening by external fixator for treatment of brachymetatarsia of the fourth ray. The hypothesis was that with external fixation it would be possible to achieve the desired length of the metatarsal with a low rate of complications. Secondarily, in cases requiring a greater amount of correction, it was hypothesized that an opportune rate of bone consolidation would be achievable using a traditional oscillating saw without predrilling or use of a cold osteotome.

METHODS

Between 2013 and 2016, 12 eligible patients and 13 feet underwent gradual metatarsal lengthening by an external fixator (MiniRail System M103, Orthofix) due to brachymetatarsia of the fourth ray. Mean age at surgery was 24.5±5.3 years (range 19-36), with mean follow-up of 22.3±8.3 months. Clinical evaluation was performed with the AOFAS lesser metatarsophalangeal-interphalangeal (MTP-IP) score. Radiographic assessment was performed on follow-up using non-weightbearing dorsoplantar foot radiographs.

RESULTS

The mean AOFAS lesser MTP-IP score improved from a preoperative score of 76.6±7.1 points (range 62-85 points) to a postoperative score of 90.3±3.0 points (range 86-95 points). The average amount of lengthening was 16.8±3.9mm (range 8-22mm). Mean shortening, final lengthening, Healing Index, period of treatment, and complications are also reported. The operative technique is described.

CONCLUSIONS

Gradual metatarsal lengthening with external fixator is an effective treatment for brachymetatarsia and can restore forefoot anatomy with good clinical outcomes, a low rate of morbidity and complications in selected cases. Particular attention should be given when treating patients with shortening >20mm.

Brachymetatarsia: One-stage Versus Two-Stage Procedures

Brachymetatarsia is a rare deformity with controversial clinical presentation. Multiple acute and gradual lengthening surgical techniques have been described for correction of this type of foot deformity. All techniques try to create a better appearance, facilitate shoeing, or solve possible transfer metatarsalgia. Either acute lengthening (1-stage procedure) or gradual lengthening (2 stages) is selected based on the patient's deformities, concerns, and clinical needs.

Intramedullary Metatarsal Fixation for Treatment of Delayed Regenerate Bone in Lengthening of Brachymetatarsia

Delayed regenerate healing after distraction osteogenesis can be a challenging problem for patients and surgeons alike. In the present study, we retrospectively reviewed the data from a cohort of patients with delayed regenerate healing during gradual lengthening treatment of brachymetatarsia. Additionally, we present a novel technique developed by 1 of us (B.M.L.) for the management of delayed regenerate healing. We hypothesized that application of intramedullary metatarsal fixation would safely and effectively promote healing of poor quality, atrophic regenerate during bone lengthening in brachymetatarsia correction. We formulated a study to retrospectively review the data from a cohort of patients with delayed regenerate healing after gradual lengthening for brachymetatarsia. All patients underwent temporary placement of intramedullary fixation after identification of delayed regenerate healing. Patient-related variables and objective measurements were assessed. We identified 10 patients with 13 metatarsals treated with intramedullary fixation for delayed regenerate healing. All 10 patients were female, with 6 (46.2%) right metatarsals and 7 (53.8%) left metatarsals treated. No complications developed with the use of this technique. All subjects progressed to successful consolidation of the regenerate bone at a mean of 44.5 ± 30.2 days after placement of intramedullary metatarsal fixation. No regenerate fracture or reoperations were noted. In conclusion, intramedullary metatarsal fixation is a safe and effective method for managing delayed regenerate healing encountered during distraction osteogenesis correction of brachymetatarsia.

Distraction Osteogenesis for Brachymetatarsia by Using Internal Device

Congenital brachymetatarsia most commonly involves the fourth ray and may be combined with metacarpal shortening. Now, many reports demonstrated the usefulness of distraction osteogenesis for lengthening of the metatarsals by using an external distraction device. In this article, we treated shortening fourth metatarsal by bone lengthening using the internal distraction device. This technique has some advantages over the method of external distraction.

A rare combination of brachymetatarsia and congenital hallux varus: case report and review of the literature

Hallux varus is defined as a medial deviation of the phalanx at the first metatarsophalangeal joint and can be congenital or acquired. Brachymetatarsia is defined as shortening of the metatarsal bones. A combination of hallux varus and brachymetatarsia is rare. A 15-year-old girl presented to our outpatient clinic complaining of problems with her feet. A distinctive hallux varus was present bilaterally combined with a brachymetatarsia of the first metatarsals. The patient reported discomfort. She was restricted in her activities and had severe psychological strain owing to the deformity. We decided on surgery. First, a Pennig MiniFixator for callus distraction of the first metatarsal bone was applied. Owing to the increased plantar subluxation of the phalanx during distraction, an extension of the external fixator was administered so that the hallux could be repositioned to a physiologically satisfying position. After sufficient callus formation, the hardware was removed 14 weeks after surgery. Thereafter, the phalanx moved back to the subluxed position. Finally, an arthrodesis of the first metatarsophalangeal joint was performed with a locking plate. Surgery should not be made only for cosmesis and associated psychological aspects; but, discomfort should be the deciding factor. The postoperative clinical and cosmetic results in our case were good, and the patient was quite satisfied. There was no longer any preoperative discomfort and pain.

Treatment of Complications after Distraction Osteogenesis for Brachymetatarsia of the Fourth Metatarsal

Congenital brachymetatarsia most commonly involves the fourth ray and may be combined with metacarpal shortening. Numerous reports have demonstrated the usefulness of gradual lengthening of the metatarsals. However, very few studies have investigated methods of recovering the lost regenerative bone. The patient was a 16-year-old girl with bilateral brachymetatarsia of the fourth metatarsal. After a long consolidation period after gradual lengthening of the fourth metatarsal by 20 mm, the patient had an hourglass-shaped regenerated bone. Therefore, we grafted a bioabsorbable hydroxyapatite and collagen composite. Six months after the surgery, well-regenerated bone could be recognized on radiographic evaluation and was resistant to refracture. Callus distraction is a method that aims to avoid donor site morbidity. The strength of artificial bone is often a problem. Bioabsorbable hydroxyapatite and collagen composite compensates for the lack of regenerated bone and distraction gap and prevents refracture, thus preventing complications after metatarsal distraction.

Brachymetatarsia with accessory navicular in right foot: A rare coincidental finding

A 33 years old female patient presented with posttraumatic pain in the right foot for which radiographs of the right foot was advised. No fracture was detected on radiographs and patient was managed conservatively on medications and posterior splint immobilization. We found coincidentally a short fourth metatarsal and an accessory navicular bone in the right foot radiographs. After 3 weeks of immobilization, she underwent mobilization of the right foot, weight bearing and intensive physio- therapy for 6 weeks. After two months of injury she was still complaining of pain on the plantar aspect of right foot which was diagnosed as metatarsalgia and operated on by excision of the neuroma present in the 3rd web space of the right foot. After surgery she was completely relieved of pain and could do activities well related to the right foot.

Comparison of the outcomes of distraction osteogenesis for first and fourth brachymetatarsia

BACKGROUND

Brachymetatarsia is the presence of an abnormally short metatarsal, and distraction osteogenesis has been used for its treatment. The purpose of the present study was to compare the outcomes of patients who underwent distraction osteogenesis for the treatment of first and/or fourth brachymetatarsia.

METHODS

The data from forty-eight patients (sixty-four feet, seventy-four metatarsals) who underwent distraction osteogenesis for the treatment of brachymetatarsia were reviewed. The indications for surgery included a metatarsal that was at least 10 mm shorter than the adjacent metatarsal and that had an unacceptable cosmetic appearance. The study group comprised thirty-two first brachymetatarsia in nineteen patients (Group A) and forty-two fourth brachymetatarsia in twenty-nine patients (Group B). The average age was twenty years in Group A and eighteen years in Group B. The average duration of follow-up was 58.1 months in Group A and 56.1 in Group B. Metatarsal length, lengthening gain, healing time and index, and the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal and lesser metatarsophalangeal-interphalangeal scores were evaluated.

RESULTS

All patients were satisfied with the final length of the metatarsal and all had achieved bone union at the time of the last follow-up. The mean lengthening gain was 17.2 mm (42.9%) in Group A and 16.3 mm (37.3%) in Group B. The mean healing index was 71.0 days/cm in Group A and 67.3 days/cm in Group B. The mean American Orthopaedic Foot and Ankle Society score was 91.2 points in Group A and 92.8 points in Group B at the last follow-up (twenty-two excellent, nine good, and one fair results in Group A, and twenty-nine excellent, eleven good, and two fair results in Group B). The most common complication was metatarsophalangeal joint stiffness, which occurred in thirteen rays in Group A and in twelve rays in Group B; malalignment of the lengthened metatarsal was observed six times in each group. No significant intergroup differences in the outcomes were found.

CONCLUSIONS

Distraction osteogenesis for first and/or fourth brachymetatarsia provided successful lengthening of a metatarsal with eventual osseous union and was associated with similar outcomes in terms of healing index, function score, and the prevalence of complications between the two groups, although frequent complications were encountered and no improvement in foot function was found.

Problems, obstacles, and complications of metatarsal lengthening for the treatment of brachymetatarsia

Metatarsal lengthening by distraction osteogenesis is a challenging procedure that is associated with various adverse results. This article presents and classifies adverse results arising from metatarsal lengthening. Our premise of classification is that not all adverse results that occur secondary to distraction osteogenesis of the metatarsal are true complications that affect the final outcome, but rather are problems and obstacles that present hurdles to completion of treatment. Our classification differentiates among problems, obstacles, and complications during metatarsal lengthening with external fixation. The cause of each adverse result is also discussed and clinical and surgical pearls to avoid these problems, obstacles, and complications are presented.

A modified surgical technique for lengthening of a metatarsal using an external fixator

Brachymetatarsia is a congenital or developmental condition that results in a short metatarsal. Problems that arise from this condition can include pain, difficulty with shoe wear, and cosmetic concerns. Multiple techniques have been described that successfully correct the deformity, including both acute and gradual distraction. We describe a modification of the technique of gradual lengthening by way of distraction osteogenesis in which an axial transarticular K-wire is incorporated into a monolateral frame, thereby increasing the stability of the construct and potentially minimizing complications.

Percutaneous distraction osteogenesis for treatment of brachymetatarsia

Brachymetatarsia is not an unusual deformity and is often associated with functional and cosmetic issues that warrant surgical reconstruction. Lengthening of the affected metatarsal can be undertaken on an acute basis in a single operative procedure that involves the use of a bone graft or by means of gradual callus distraction. Because of the risk of metatarsophalangeal joint malalignment, it is important for the surgeon to take steps to stabilize the joint during the lengthening process. In this report, a percutaneous method of callus distraction for repair of brachymetatarsia and maintenance of metatarsophalangeal joint alignment is presented.

Treatment of brachymetatarsia by distraction osteogenesis

Metatarsal lengthening by distraction osteogenesis was performed on 17 brachymetatarsia patients with 39 metatarsal bones. To lengthen the first metatarsal in an attempt to prevent development of varus deformity of the hindfoot after lengthening, horizontal lengthening in the anterior direction was performed rather than lengthening through the anatomical axis. In addition, care was taken to ensure that the fourth metatarsal bone screw did not interpose with the fifth extensor tendon during the fourth metatarsal lengthening. Lengthening was successful except in 1 case with mean lengthening of 19.5 mm (48.8%) for the first metatarsal and 17.1 mm (36.2%) for the fourth metatarsal. Because of joint stiffness, plantar capsulotomy was performed on 7 cases, 6 of which had been previously operated on bilaterally. Varus deformity of the hindfoot after the first metatarsal lengthening and entrapment of the fifth extensor tendon after the fourth metatarsal lengthening was not detected in any case.

External fixation for the foot and ankle in children

During the last decade, external fixation for the pediatric foot and ankle has evolved as a result of advances in technology (eg, Taylor spatial frame, hydroxyapatite-coated external fixator pins) and preoperative deformity planning. Although complications are common, most are minor and can be addressed nonoperatively while treatment continues. This article reviews the indications and applications of external fixation for soft tissue contractures, idiopathic and teratologic clubfoot, osteotomies, metatarsal lengthening, tibial lengthening, and foot and ankle trauma.

Brachymetatarsia

Brachymetatarsia is a rare clinical entity that presents a complicated case to the treating surgeon. One-stage lengthening procedures with a variety of biologic and synthetic implants are preferred for metatarsals that only need to be lengthened up to 15 mm, whereas gradual lengthening allows for greater length gain and concomitant lengthening of the soft tissues. Adjacent metatarsal shortening may be used in conjunction with lengthening procedures to restore the parabolic arc of the metatarsal heads. Management should be tailored to the patient's individual deformity and expectations. Individualization of surgical techniques and patient selection criteria can result in a cosmetic, functional result that is satisfactory to the clinician and the patient.