Elizabeth W. Hubbard, MD
Brachymetatarsia is a bone condition in which one or more of someone’s toes is shorter than the surrounding toes. Usually this affects the fourth, first or fifth toes.1 It can occur on one side or it can affect both feet. It is not actually the toe bones that are short but rather the long bone attached to the toe (metatarsal) that is short.
The cause of brachymetatarsia is not completely clear. It can occur in otherwise healthy patients with no known medical problems. It can also be seen in patients with a range of underlying conditions, including Down Syndrome, Apert Syndrome, Diastrophic Dysplasia and Albright Osteodystrophy.1 It can develop if a person injures a growth plate of a toe early in life and the growth plate closes prematurely.
Most patients do not report functional limitations relating to brachymetatarsia.2 However, some patients do notice that having one or more shorter toes alters how they are able to bear weight through the foot and this can cause pain in the surrounding, longer toes.3 Patients may also notice difficulty wearing particular types of shoes, such as high-heels. The most common complaint among patients is related to the cosmesis (the appearance of the foot) of the deformity, particularly if a patient wants to walk barefoot or with open-toe style shoes.4
A thorough examination requires an evaluation of the entire patient. If a patient is born with brachymetatarsia, it is important that the physician evaluate for other conditions as well. Wearing or bringing a pair of shorts to your appointment is helpful as it allows your doctor to perform a complete examination of your legs and feet. You doctor will likely watch you walk, both with and without shoes. He or she will also check for a leg length discrepancy, as sometimes a size difference in the toes can be a sign of altered growth in another part of the leg or foot. A leg length difference can be checked by having you stand with your back to the doctor so that the doctor can evaluate if your pelvis and shoulders are level when you stand. If your pelvis does not seem to be level (one side is higher than the other), this can be a sign that one leg is shorter than the other. Your doctor may place one or more wooden blocks under the presumed short leg until your pelvis seems level and the height of the blocks used is an estimation of the difference between your legs. Your doctor will also likely check your range of motion at your hips, knees and ankles to determine if there is any unusual difference between how the joints move on one side relative to the other, as this can sometimes indicate a problem in or around a joint. He or she will likely also check that your thighs, calves and overall foot length are similar between the right and left sides.
A thorough foot examination is critical. This includes evaluating how the joints of the ankle, midfoot and toes move. In addition, strength and sensory testing will be done.
Your doctor will likely get standing x-rays of both feet to compare the toe lengths and also evaluate for other underlying issues with the bones and joints of the foot that may be contributing to or associated with the brachymetatarsia. Often, in a situation where a person has developed brachymetatarsia after a trauma, there is evidence on the x-ray of the prior injury. In patients who have brachymetatarsia involving only 1 foot, x-rays of the unaffected foot are important as these can provide a “blueprint” for the goal of treatment, should you and your doctor decide that surgery is the best option. Some physicians may also order a test called a pedobarograph, which is a study that shows how you distribute your body weight through each foot when you walk. This can be helpful for surgical planning but is also useful after surgery as a comparison study to demonstrate if/how a surgery has changed the way you distribute your body weight through your foot while walking.
Because many patients do not report a functional limitation or pain related to this condition, non-surgical treatments can be appropriate. This includes shoe modification and/or using a shoe-filler if needed to account for the shorter toe(s). However, for patients who have pain in the surrounding toes or those who are not happy with the appearance of the foot or feel that the condition limits his or her options with shoe wear, surgery may be appropriate.
Surgery often involves lengthening a bone in the short toe(s). When less than 1cm of length is needed to restore appropriate length to the toe, the toe can often be lengthened at the time of surgery. This is called an “acute correction”. This means that the bone is cut and that each piece of the bone is pulled apart until the bone is the new, appropriate length. The two pieces of the bone are then re-connected using a plate and screws or a pin through the toe. The gap that is created is often filled with bone graft or a type of bone substitute. This procedure is best done when only a small amount of lengthening is needed because:
1. You body has to fill in the gap that is created at the time of the lengthening. The larger the gap that is created, the longer and more difficult it is for your body to heal this gap.
2. Lengthening a bone requires that all of the surrounding tissue, such as the skin, tendons, blood vessels and nerves, have to lengthen as well. Sometimes if these tissues are stretched too much, it can cause problems such as joint stiffness, a bent position of the toe or pain.
If a toe is so short that your doctor does not think it would be safe to lengthen it during the surgery, your doctor may suggest that you have a “gradual correction”. This means that you would have a special type of orthopaedic device called an external fixator applied to your foot. At the time of surgery, your doctor places multiple metal pins through the skin and into the bone that is being lengthened (usually 4-5 pins). These pins stick out of the skin and are attached to a special type of rod, connecting the 4 pins to one another. Sometimes a pin is placed through the end of the toe. The doctor then carefully cuts the bone that is being lengthened but leaves the ends of the cut bone close together. About 1 week after the surgery, your doctor will instruct you on how to adjust the external fixator to slowly lengthen the distance between the pins, which slowly lengthens the distance between the 2 ends of your bone. Your toe gradually gets longer while your body gradually fills in the gap that is created with new bone. When more than 1 to 1.5 cm of length is needed to lengthen the toe, this is usually the safest way to lengthen the bone.
Your doctor determines the amount of length that is needed based off of your x-rays and the physical appearance of the foot. Ideally, each of the toes in the foot should have an alignment such that the first toe is either longer or the same length as the second toe, then each subsequent toe is slightly shorter. In cases in which a patient has brachymetatarsia only affecting one foot, it is generally the goal to lengthen the toe(s) so that the affected foot appears similar to the unaffected side. In cases where toes on both feet are affected, the goal of treatment is to lengthen both sides safely and symmetrically to achieve a symmetrical cascade to the toes on both feet.
After external fixator surgery patients are generally allowed to walk on their heel. Your surgeon will instruct you on how to care for the pin sites. Generally physical therapy is not required, although it is important to stretch the toe at home. The fixator can potentially be removed in the office, or it might require an outpatient surgery (one where you go home the same day).
There can be a number of complications with lengthening procedures.4 Regardless of how the lengthening is performed (acute or gradual), stiffness of the joints to the toe is the most common problem.5-7 This is more common when more length is needed, particularly when an acute lengthening is being done. With gradual lengthening, the lengthening process can be stopped or slowed if the patient develops stiffness, so while stiffness is common, it can potentially be diagnosed and treated during the lengthening process. The gap that is created between the 2 normal bone ends is also a site of weakness so fracture (breaking the bone that is being or has been lengthened) is possible. Delayed bone healing may require a secondary surgery, such as bone grafting or placement of an intramedullary wire to stabilize the bone.3, 4, 8 Patients who have an external fixator are also at risk for pin site infection, pin loosening or pin breakage. Patients can also develop angular deformities of the toe and/or foot due to the lengthening and these may require a surgery to fix if these deformities cause pain or a functional problem.
Outcomes are generally good after surgery.2, 3, 7, 9-12 Patients who choose surgery have been shown to report less pain (if the condition was painful prior to surgery) and are often pleased with the improved appearance of the foot. Because there are potential complications from lengthening procedures, it is important to see a surgeon who performs this type of bone lengthening as they will have the most experience and best be able to educate you about the process prior to surgery and guide you through the treatment and recovery.
1. Fahim R, Thomas Z, DiDomenico LA. Pediatric forefoot pathology. Clin Podiatr Med Surg. 2013 Oct;30(4):479-90. Epub 2013/10/01.
2. Robinson JF, Ouzounian TJ. Brachymetatarsia: congenitally short third and fourth metatarsals treated by distraction lengthening–a case report and literature summary. Foot Ankle Int. 1998 Oct;19(10):713-8. Epub 1998/11/04.
3. Lamm BM. Percutaneous distraction osteogenesis for treatment of brachymetatarsia. J Foot Ankle Surg. 2010 Mar-Apr;49(2):197-204. Epub 2009/12/22.
4. Lamm BM, Gourdine-Shaw MC. Problems, obstacles, and complications of metatarsal lengthening for the treatment of brachymetatarsia. Clin Podiatr Med Surg. 2010 Oct;27(4):561-82. Epub 2010/10/12.
5. Lee KB, Park HW, Chung JY, Moon ES, Jung ST, Seon JK. Comparison of the outcomes of distraction osteogenesis for first and fourth brachymetatarsia. J Bone Joint Surg Am. 2010 Nov 17;92(16):2709-18. Epub 2010/11/19.
6. Levine SE, Davidson RS, Dormans JP, Drummond DS. Distraction osteogenesis for congenitally short lesser metatarsals. Foot Ankle Int. 1995 Apr;16(4):196-200. Epub 1995/04/01.
7. Sascha Dua R, Grace D. One-stage lengthening for congenitally short metatarsals. The Foot. 2004 (14):164-8.
8. Lamm BM, Moore KR, Knight JM, Pugh E, Baker JR, Gesheff MG. Intramedullary Metatarsal Fixation for Treatment of Delayed Regenerate Bone in Lengthening of Brachymetatarsia. J Foot Ankle Surg. 2018 Sep – Oct;57(5):987-94. Epub 2018/07/22.
9. Choi IH, Chung MS, Baek GH, Cho TJ, Chung CY. Metatarsal lengthening in congenital brachymetatarsia: one-stage lengthening versus lengthening by callotasis. J Pediatr Orthop. 1999 Sep-Oct;19(5):660-4. Epub 1999/09/17.
10. Hosny GA, Ahmed AS. Distraction osteogenesis of fourth brachymetatarsia. Foot Ankle Surg. 2016 Mar;22(1):12-6. Epub 2016/02/13.
11. Jones MD, Pinegar DM, Rincker SA. Callus Distraction Versus Single-Stage Lengthening With Bone Graft for Treatment of Brachymetatarsia: A Systematic Review. J Foot Ankle Surg. 2015 Sep-Oct;54(5):927-31. Epub 2015/05/23.
12. Kim HT, Hong SM, Kim IH. Treatment of Brachymetatarsia Involving the Great Toe. JB JS Open Access. 2018 Jun 28;3(2):e0046. Epub 2018/10/04.