Use of internal callus distraction in the treatment of congenital brachymetatarsia

Callus distraction for brachymetatarsia - A comparison between an internal device and the external fixator

BACKGROUND

Symptomatic patients with severe brachymetatarsia are commonly treated with callus distraction using external mini-fixator (EF) or internal device (ID). This study points out advantages and limitations of both methods comparing clinical and radiographical parameters.

METHODS

Retrospective analysis of 21 metatarsal bones in twelve patients. Twelve metatarsals were treated with ID (Genos Mini), nine with EF (MiniRail).

RESULTS

Mean lengthening distance was 17.3 mm using EF and 11.7 mm using ID (p = 0.016). Adverse results were observed in 89% of metatarsals treated with EF and in 33% treated with ID (p = 0.011). Postoperative surgical intervention was required in 33% using EF compared to 0% using ID (p = 0.031). Mean total German Foot Function Index (FFI-T) improved from 49 to 33 using EF and from 47 to 22 using ID (p < 0.001).

CONCLUSION

CD is a reliable surgical treatment for BMT. Surgeons should be aware of implant-related advantages and complications when counseling patients about treatment options.

Brachymetatarsia: Surgical Management, Case Report, and Literature Review

Background

Brachymetatarsia is defined by an abnormal shortening of the metatarsal bone. This rare condition is mostly primary and congenital. Consequences of this malformation are both esthetic and functional, due to pain and mechanical problems in the forefoot. Surgical management is an important part of patient care. There are two main options: gradual lengthening by progressive callotosis distraction using an external fixator and one stage lengthening using bone graft and osteotomy of the bone. This review presents two cases using the one stage lengthening surgical management method. We also discuss some reports in the literature with the aim to compare the advantages and disadvantages of the two surgical methods. Literature concerning the surgical management of brachymetatarsia was identified using the PubMed and Google Scholar databases. Patient Presentation. We describe two female patients aged 20 and 26 years who underwent one stage lengthening surgery of the fourth toe with isolated brachymetatarsia using an iliac bone graft and internal fixator plate. The two patients had a lengthening of around 10 mm after postoperative evaluation. No skin complications were noted, but one of the patients reported flexor stiffness after surgery. Concerning the functional and cosmetic aspects, the two patients are satisfied with the management.

Conclusions

In the literature, one stage lengthening seems to be the most favorable option for the care of brachymetatarsia. Studies show a short healing time and fewer complications like infection, stiffness, malalignment, and malunion. Some reviews note the utility of the gradual lengthening of severe brachymetatarsia when a longer lengthening is necessary. There is no definite consensus concerning the management of brachymetatarsia.

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.

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

Literature Review on Brachymetatarsia

Brachymetatarsia is a malformation characterized by an abnormal reduction in the length of 1 or more metatarsal bones. It occurs because of early closure of the growth plate of the affected metatarsal. Generally, it is caused by a congenital disorder and it usually occurs bilaterally. With a greater prevalence in females, it most often affects the fourth metatarsal, followed by the first metatarsal. Surgical treatments proposed include using external mini-fixators or bone grafts in a single step to lengthen the metatarsal. In this review, 62 scientific articles about brachymetatarsia were analyzed with key demographic and epidemiological aspects of this pathology. The prevalence of bilateral brachymetatarsia was 47%, and the female to male ratio was 10.53:1. Both these findings appear to contradict the usual data reported for brachymetatarsia. A better understanding of this disorder will enable an appropriate therapeutic approach according to the psychological and social profile of affected individuals.

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.

Callus Distraction Versus Single-Stage Lengthening With Bone Graft for Treatment of Brachymetatarsia: A Systematic Review

Brachymetatarsia deformity is a cosmetically displeasing anomaly that can become physically symptomatic. The surgical techniques most commonly used to repair the anomaly include single-stage lengthening with a bone graft, callus distraction, or a combination of bone grafting and callus distraction. A systematic review of the published data was performed to compare the outcomes of these 3 surgical procedures. A total of 61 studies reporting the use of callus distraction or single-stage lengthening, or both, for the treatment of brachymetatarsia were included in the present review. The incidence of major postoperative complications after callus distraction, single-stage lengthening, and the combination procedure was 49 (12.62%), 13 (3.72%), and 3 (33.33%), respectively. The number of minor complications with callus distraction, single-stage lengthening, and the combination procedure was 152 (39.18%), 55 (15.76%), and 1 (11.11%); the mean percentage of the original length achieved was 37.36%, 25.98% and 36.00%; and the mean length achieved was 17.5, 13.2, and 14.0 mm, respectively. The healing index (mo/cm) and healing time was 2.31 and 16.04 weeks, 1.90 and 9.35 weeks, and 3.93 and 14.62 weeks for callus distraction, single-stage lengthening, and the combination procedure, respectively. Our findings indicate that the callus distraction technique is associated with greater length gained but results in greater complication rates and requires almost twice the time to heal. Single-stage lengthening with a bone graft was associated with fewer complications and faster healing times than callus distraction but with lesser gains in length. From the information reported in the studies we reviewed, the prevalence of bilateral brachymetatarsia was 44.52%, and the female/male ratio was 13.7:1. Both of these findings seem to contradict the usual data given (72% for bilateral brachymetatarsia and a female/male ratio of 25:1).

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.

One-stage metatarsal lengthening by allograft interposition: a novel approach for congenital brachymetatarsia

BACKGROUND

Congenital brachymetatarsia, a shortened metatarsal bone, can be corrected surgically by callus distraction or one-stage lengthening using bone graft.

QUESTIONS/PURPOSES

We asked whether one-stage metatarsal lengthening using metatarsal homologous bone graft could improve forefoot function, lead to metatarsal healing, restore metatarsal parabola, and improve cosmetic appearance.

PATIENTS AND METHODS

We retrospectively reviewed 29 patients (41 feet) in whom we lengthened 50 metatarsals. Surgery consisted of a transverse proximal osteotomy of the metatarsal shaft and interposition of a metatarsal homologous bone graft (average, 13 mm long) fixed with an intramedullary Kirschner wire. Minimum followup was 3 years (mean, 5 years; range, 3-11 years).

RESULTS

Bone union was achieved in all cases. The mean preoperative American Orthopaedic Foot and Ankle Society score was 37 points (range, 28-53 points) and the mean postoperative score was 88 points (range, 74-96 points), with an average improvement of 51 points. Radiographically, the mean gain in length was 13 mm (range, 10-15 mm), and the mean percentage increase was 23%.

CONCLUSIONS

One-stage metatarsal lengthening using interposition of metatarsal homologous bone graft to correct congenital brachymetatarsia has low morbidity for the patient, limited complications, short recovery times, and restores forefoot anatomy.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Lengthening of the first metatarsal through an arthrodesis site for treatment of brachymetatarsia: a case report

Brachymetatarsia of the first metatarsal is an uncommon condition, but one that is amenable to treatment by lengthening via distraction osteogenesis, a process that employs 2 groups of pins of an appropriate external fixator inserted in the metatarsal to apply gradual distraction across an intervening osteotomy. We present the case of a female, aged 13 years, who presented with congenital bilateral first brachymetatarsia and left foot pain due to transfer metatarsalgia. The short and plantarflexed first ray could not accommodate both groups of fixator pins, even with the fixator set at its shortest length. An alternative strategy was devised that reduced the degree of plantarflexion using a tarsometatarsal arthrodesis, which effected subsequent lengthening through the healing fusion site. Lengthening commenced after 10 days and continued over a period of 52 days, at a rate of 0.5 mm to 1.0 mm per day. Consolidation occurred at 20 weeks with a final increase in length of 25 mm. The patient returned to vigorous sporting activity 1 year after removal of the fixator. To our knowledge, this is the first account of a metatarsal-lengthening arthrodesis at the tarsometatarsal level.