Complications of distraction osteogenesis in short first metatarsals

Radiological Biometric Study of Metatarsals and Phalanges

Introduction

Several diseases affect the forefoot bones. Relative dimensions of the forefoot bones are important considerations for preoperative and postoperative assessment of surgeries. The choice of a particular surgery over another can also be made if the surgeon knows the length to which a bone needs to be lengthened or shortened in comparison to other bones of the forefoot.

Aim

To measure the dimensions of the metatarsals and phalanges on standardized radiographs and to determine possible correlations amongst them.

Materials and Methods

A cross-sectional prospective study was conducted on 60 volunteer participants of either sex. The dimensions of metatarsals and phalanges were measured on standardized radiographs of both feet in 60 healthy adults. The mean, range and standard deviation were calculated. Correlation analysis was done to assess the association between the variables.

Results

The first metatarsal was the shortest (56.42±4.41 mm in males and 50.09±3.06 mm in females) and widest of all metatarsals (13.7±1.00 mm in males and 11.7±0.91 mm in females). The first proximal phalanx was the longest (28.0±2.40 mm in males and 25.8±2.21 mm in females) and the fifth distal phalanx (5.2±1.33 mm in males and 4.4±1.03 mm in females) was the shortest of all phalanges. A strong correlation (p<0.001) exists amongst the lengths of metatarsals, proximal phalanges and middle phalanges, within their own groups.

Conclusion

Correlation of the lengths and widths of the forefoot bones amongst themselves and between types can be calculated mathematically utilising standardized radiographs. This helps in assessment of forefoot disorders, choose an appropriate surgical technique and postoperative evaluation.

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.

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.

Metatarsal reconstruction with a fibular osteocutaneous flap: a novel approach utilizing virtual surgical planning

Supplemental Digital Content is available in the text.

Summary:

Craniofacial reconstruction remains the main application for virtual surgical planning (VSP). We present a case in which this technology was applied to reconstruct a bony defect of the first metatarsal bone from a gunshot injury. VSP was used to facilitate a 1-stage reconstruction with a fibular osteocutaneous flap. A template of the reconstructed bone was designed based on the virtual mirror-image, noninjured bone. Prefabricated cutting guides facilitated precise shaping of the vascularized bone accounting for location of perforators. Successful reconstruction of the metatarsal bone was achieved with excellent functional outcomes. We believe that VSP can be a valuable tool in reconstruction of metatarsal bones by facilitating precise intraoperative shaping and anatomic orientation of the vascularized flap and reducing flap ischemia and operative time.

How to avoid complications of distraction osteogenesis for first brachymetatarsia

BACKGROUND AND PURPOSE

Distraction osteogenesis may be used for the treatment of brachymetatarsia. However, few reports have been published on first metatarsal lengthening by this method. We evaluated the complications of distraction osteogenesis for first brachymetatarsia and here we provide a solution.

PATIENTS AND METHODS

16 patients (27 feet) underwent distraction osteogenesis for first brachymetatarsia. Mean age at time of surgery was 20 (12-34) years and mean duration of postoperative follow-up was 5 (2-13) years. A unilateral external fixator was fixed at the medial aspect of the metatarsus. The distraction axis was parallel to the plantar surface of the foot in the sagittal plane and to the second metatarsal axis in the transversal plane.

RESULTS

First metatarsal length expressed as a proportion of second metatarsal length was 60% (55-64). Average degree of metatarsal lengthening was 42% (34-54), and the average lengthening index was 64 (39-93) days/cm. The most common complication was stiffness of the metatarsophalangeal joint (12 feet). Deformities that included cavus foot and hallux valgus occurred in 3 feet each, and callus fractures occurred in 3 feet. The other complications were pin breakage and pin tract infection in 2 feet each.

INTERPRETATION

Distraction osteogenesis for first brachymetatarsia can give satisfactory cosmetic and functional results. However, several complications are commonly encountered. This report on complications and their solutions may help those attempting distraction osteogenesis for first brachymetatarsia.

Lengthening of short bones by distraction osteogenesis--results and complications

We performed bone lengthening surgery on 12 metacarpals and 14 metatarsals of 15 patients. The mean age for metacarpal and metatarsal lengthening was 14.5 (10-21) and 17.5 (10-25) years, respectively. We used a unilateral or a circular external fixator. The mean healing index of the metacarpals and metatarsals was 1.6 (1.1-2.3) and 1.6 (1.0-2.0) months/cm, respectively. The mean increase in metacarpal and metatarsal length was 17.6 (13-26) and 24.3 (20-30) mm, respectively. The functional scores of the metatarso-phalangial (MTP) joint of lengthened metatarsals for the lesser toe were excellent in 12 and good in two cases based on the American Orthopaedic Foot and Ankle Society (AOFAS) scoring system. Complications were seen in six of the metatarsal lengthening cases including four angulations, one subluxation and one non-union. We conclude that the periosteum must be protected with percutaneous osteotomy and lengthening should be performed at a rate of 0.25 mm twice a day and should not exceed 40% of the original bone length (or >20 mm).