METATARSAL FRACTI]RES

Bradley D. Castellano, DPM Stepben V. Corey, DPM TbomasJ. Merrill, DPM John A. Rucb, DPM

As with many common disorders of the , the displaced fractures, stress fractures, joint disloca- area of metatarsal fractures has received only tions, intra-articular fractures, severely comminut- superficial attention in historical and current med- ed and even compound fractures. The sllrgeon ical and surgical discr-rssions. General principles must have a thorough working knowledge of of fracture management have been sparingly these injuries in the specific region and unique applied to the topic in most ofihopedic and podi- anatomy of the forefoot. The full scope of poten- atric texts. The fifth metatarsal, however, has tial injury must be appreciated to avoid misdiag- received some degree of attention uncler the nosis and inappropriate treatment. eponym of the Jones' fracture. The eponym how- The variety of injuries to the metatarsal ever is often misapplied to the common avulsion region can be systematically classified. This type fracture of the fifth metatarsal base. Most refer- of classification can serve the same purpose as ences ciealing with the subject are interesting per- the Lauge-Hansen system in fractures. A sonal experiences with metatarsal fractures and working knowledge of the mechanism of injury is an attempt to introduce a new or re-visited tech- also the key to successful management of many nique for the management of a unique or bizarre of the common injuries through conservative injury. Figura presents a iogical and rather com- methods or closed reduction techniques. plete classification of metatarsal fractures and dis- Complete clinical and radiographic evalua- cusses treatment.l tion are essential stepping stones in the success- State of the art has yet to be described in the ful management of metatarsal fractures. A management of metatarsal fractures. However, detailed description of the clinical appearance of the tools are avallable for a more consistent and the injury may often be the clue to a major injury definitive course of treatment. that may not be ful1y radiographically demon- Diagnosis and treatment of metatarsal frac- strated because of spontaneous reduction. A min- tures is dependent upon: imum of three radiographic views, dorsoplantar, 7, A comprehensive knowledge of metatarsal lateral, and oblique, are essential in the initial fractures, evaluation of any forefoot trauma that may 2. A thorough clinical and radiographic evalua- include metatarsal fractures. tion, and Armed with a ftr11 appreciation of potential 3. A sound working knowledge of the principles injury patterns the surgeon must apply a similar of treatment including: closed reduction tech- advanced level of practice to the techniques of niques healing internal fixation. management. Conservative methods or closed The topic of metatarsal fractures can be a reduction techniques do not necessarily fall into comprehensive microcosm of orthopedic trauma. the category of outdated skilis. Indeed, Charnley The variety of injuries can include simple non- presents a scientific basis to the principles and

294 techniques of closed redr-rction in his text The GENERAL CONSIDERATIONS IN Closed Treatment of Common Fractures.2 The sci- METATARSAL FRACTURES entific application of the principles of closed reduction inciude: The general topic of metatarsal fractures is very 1. The mechanism of injury poorly described in general orthopedic and podi- 2. The solt tissue hingc atric literature. Most attention has been focused 3. The closecl reduction technique on specific and definable injuries such as the 4. Maintenance of the reduction via the plaster. Jones' fracture, Lisfranc injury, and ar'.u1sion frac- These basic concepts are extremely impor- tures of the base of the fifth metatarsal. Common tant for effective and consistent results through fractures of the metatarsals are casually described closed methods. as being caused by direct trauma or some form of Open reduction and internal fixation of impaction. \fhile a detailed knowledge of the metatarsal fractures may be more fashionable in mechanism of injury for common fractures may the current surgicai theater. While there are not be essential to successful management, it definitive indications for ORIF, such as intra- does demonstrate the level of minor significance articular fracture and severe non-reducible defor- that common metatarsal fractures have been mity, the indications for ORIF in more common given. injuries remains less distinct. It is through a com- Factors which must be taken into considera- bined appreciation of a more normal functional tion in evaluation of metatarsal fractures include: result and the concepts and skills of rigid internal displacement, angulation deformity, shortening, fixation that a logical approach to the manage- and comminution. The extent of these factors will ment of metatarsal fractures can be devised. play malor roles in determining the most appro- priate form of treatment for each fracture. CIASSIFTCAIION NECK FRACTURES A u,.orking outline for categorizatton of metatarsal fractures can be summarized as follows: The most common fractures at the level of the I. General Fractures metatarsal neck are transverse or shofi oblique in A. Location configuration. Transverse fractures are typically B. Configuration bending fractures caused by direct trauma from a IL Special Categories falling object. One of the most common trans- A. First metatarsal fractures verse fractures at the metatarsal neck, however, is 1. Biomechantcal significance not caused by direct trauma but rather fatigue as 2. Avulsion peroneus longus seen in the typical of the lesser B. Fifth Metatarsal Fractures metatarsals. 1. Avulsion Fractures The short oblique fracture at the neck of the 2. Jones'Fractures metatarsal is caused by a bending force applied 3. Oblique Neck Fractures with Butterfly w-ith longitudinal compression as seen in the Fragment "brake foot" follow-ing an automobile accident. C. Intra-artictilar Fractures (inch-rdes frac- Direct pressure is applied through the plantar ture/dislocation) surface of the metatarsal heads forcing the 1. Lisfranc Joint metatarsal head up and back. A similar mecha- 2. Metatarsophalangeal Joint nism can create a short oblique fracture with 3. Metatarsocuneiform/cuboid Joint plantar displacement or angulation of the D. Stress Fractures metatarsal head. This injury can occur with E. Epiphyseal Fractures extreme extension of the digit on the metatarsal F. Open Fractures head and an impaction force causing a violent plantar bending force at the metatarsal neck. Sim- ilar displacement can also occur in either a medi- al or lateral direction depending on the angle of pressure directed against the metatarsai head.

295 MID-SIIAFT FRACTI]RES Fifth Metatarsal Fractures

The same mechanical forces can create fracture at The fifth metatarsal is subject to the same type of the mid-shaft level of the metatarsal. Direct general fractures as the other metatarsal seg- impact from a falling object is likely to create a ments. However, two unique fractures to the fifth transverse fracture pattern. Long oblique fractures metatarsal are classically described. of the metatarsal involving the mid-shaft region Auulsion fracture, Avulsion of the styloid can be seen with direct linear impact through the process of the base of the fifth metatarsal is clas- longitudinal axis of the metatarsal. Torsion frac- sically described as a consequence of an inver- tures of the metatarsals are rare. sion injury of the foot and is a direct result of traction from the . This BASE FRACTURES fracture usually heals with minimal complications. However, significant displacement can occur with Fractures identified at the base of the metatarsals separation of the fracture fragments due to pull of must raise suspicion as "tell tale" signs of more the peroneus brevis tendon and may require sur- major injury. Small obscure fractures such as arr gical intervention for reduction and fixation. from the base the second of Jones'fracture. The classic Jones' fracture is metatarsal may be suggestive of a more signifi- a transverse fracture at the base of the fifth cant fracture/dislocation of the Lisfranc joint. metatarsal approximately one centimeter distal to Transverse fractures can occur at the metatarsal the metatarsocuboid joint. It has been historically bases without disruption of the tarsometatarsal labeled as a poor healing fracture due to joint. decreased vascularity of the metaphyseal segment of the metatarsal base. However, this concept is SPECIAL CATEGORIES OF Llnsuppofted and more logically explained on the METATARSAL FRACTURES basis of mechanical instability of this unique frac- ture location. The proximal end of the fifth The grouping of special categories serves several metatarsal is securely immobilized by ligamen- purposes. Many special fractures occur only in tous attachment, interlocking joint articulation, specific metatarsals and are caused by unique and insertion of a maior tendon. and well defined mechanisms of injury. Certain The distal segment of the fifth metatarsal, fractures have significant functional or healing unlike the internal metatarsals, is only stabilized significance. Each of the categories will be dis- by intermetatarsal attachments on one side. The cussed briefly as they have been described in distal segment of the fifth metatarsal is subject to detail in other references. motion in any phase of weightbearing and acts as a highly mobile lever arm with motion focused at First Metatarsal Fractures the proximal fracture site. It is this mechanical instability and unrestrained motion that predis- Fractures of the first metatarsal carry special sig- poses this unique fracture to delayed union and nificance because of the primary functional role even non-union. of the first ray segment. Any fracture that creates significant shortening or angular deformity of the first metatarsal can significantly alter the overall Intra-Articular Fractures biomechanical function of the ray and the foot as Intra-articular fractures in general are a unique a whole. and special category. Fracture involving metaphy- A unique fracture of the plantar Tateral seal and subchondral bone with resultant damage aspect of the base of the first metatarsal can be to articular cartilage can produce permanent dis- produced by traction peroneus of the longus ten- ability more than any other fracture. In these don. An ar,rrlsion fracture involving the insertion instances the idealistic principles of anatomic of the peroneus longus is a rare but specific frac- reduction and rigid internal fixation are ture unique to the first metatarsal. Other subtle paramount for successful heaiing with minimal fractures of the first metatarsal base mav be seen disability and loss of joint function. in Lisfranc injuries.

296 LisfrancJoint Surgical Seminar syllabus on this topic. The same basic classifications and principles of treatment One of the most disabling injuries to the foot can be applied to epiphyseal fractures of the includes the muitiple and complex fracture/dislo- metatarsals. cation of the tarsometatarsal or Lisfranc joint. Cain summarized the injury in his presentation at Open Fractures the Doctors Hospital Seminar in 1985. \7i1ey's article Tbe Mechanism of Tarsometatarsal Joint Open or compound fractures present special Injuries gives a classic description of the classifi- treatment considerations. The basic fractures are cations and different mechanisms involved.3 no different from those mentioned above other than the environment within which they exist. Dr. Metatarsophalangeal Joint Martin will present a detailed discussion concern- ing the management of open fractures in the trau- Intra-articular fracture into the metatarsopha- ma section of this syllabus. langeal joint is not a commonly encountered There are many other unique and challeng- injury. Injury into the joint more commonly ing injuries that can involve the metatarsals such involves the base of the proximal phalanx rather as crush in1'uries, amputation, and even missile than the afticular aspect of the metatarsal head. wounds. Each of the special areas offers addition- As with any inlra-articular fracture, accurate al considerations in the overall treatment plan. anatomic reduction and rigid internal fkation are the primary goals in treatment. TREATMENT Stress Fractures Treatment of metatarsal fractures has historically been left to the personal experience of the indi- Stress fracture of one or more of the intermediate vidual surgeon. Very little is written regarding three metatarsals is one of the more common basic guidelines, indications, or criteria. Tech- fracture injuries of the metatarsals. The basic eti- niques also vary with each physician and most ology includes repeated excessive load force to often fall into the basic realm of a below-knee the metatarsal with resultant fatigue or stress frac- cast or fracture shoe. Open reduction and inter- ture at the weakest polnt of the bone. Clinical nal fkation of metatarsal fractures has previously conditions that can lead to this injury include: had very few primary indications. This rather out- l. Over-use syndromes seen in athletes, military dated approach is merely reflective of the tradi- personnel, occupational settings and other tional goal of management of metatarsal fractures, high stress activities. i.e. to allow the bone to heal. 2. Functional imbalance seen in biomechanical Vith a greater appreciation of the complex conditions and iatrogenic surgical disorders. and integral function of the metatarsals as a unit, 3. Osteoporosis the modern goals of treatment are more oriented The typical stress fracture is a non-displaced toward the functional end result. The primary transverse fracture at the neck of the metatarsal. goal of fracture treatment of the metatarsals is to The injury is often misdiagnosed early on in the return the injured part to full function with clinical presentation due to lack of radiographic minimal sequelae to the individual and adiacent evidence of fracture or bone healing. The fracture stftictures. is classically identified two to three weeks into The key components of this surgical philos- the clinical course as active bone callus becomes ophy include anatomic reduction and the princi- evident in the healing process. ples and techniques of rigid internal fixation. Conservative management through the principles Epiphyseal Fractures and techniques of closed reduction and external plaster fixation are still the primary and initial The unique category of epiphyseal fractures is basis of treatment for most of the common classically described in the Salter-Harris ciassifica- metatarsal fractures. However, the surgeon must tion system. Banks presents a discussion and lec- be aware of those more complex iniuries which ture in the 1987 edition of the Doctors Hospital

)c)7 will require surgical inten'ention and the unique Kavanaugh JH. Brower TD. Nlann R\r: The and advanced skills of rigid internal fixation. revisited. .J Bone.Joiilt Surg 60A:776, t978. The clinical conditions and the techniques of l,llarcinko DE, Rappaport NU, Gorclon S: Post traumatic brachymetatarsia. Foot Surg23:4i7, 1,984. open reduction and internal fixation of metatarsal J McDonald Rl, Longfellorv JN. Parkinson DE. Edehnan RD: fractures will be discussed in detail in the lecture Multiple traLlmatic fiactures of the lesser metatarsals: a presentation of metatarsal fi'actures at the Surgicai case report. J Am Podiatr AssocT6:283, 7986. Seminar. Pritsch M, Heim M, Tauber H, Horoszou,ski H: An unusual fracture of the base of thc fifth metatarsal ltone. .l Trau- REFERENCES ma 20:i30. 7980. Rao JP. Banzon MT: Irreclucible clislocation of the metatar- sophalangeal joints of the ibot. Clin Ortbr.tp 11i221. 1. F-igura M: Metatarsal fractures. In Scurran BL Gd). Clin 7979. Pocliatry'.'il/B Saunders. I']hilac1elpl-ria, vol 2. no 2, pp Rocku,ood CA, Green DP (ecls): ?-ractures. r.ol 2, Lippin 24- )7- . April. l()xs. Jts cott Philadelpl"ria. 1980, pp 7172-1.181. 2. Charnley J: Tlte Closed Treatment o.f Comnton Fracttu"es. Schn'artz \-H, Buchan DS, Marcinko DE: I,Iodified tension ed 3. Churcl.rill-Lil.ingston, London, 19i11. band rviring for lnternal fixation of the surgical 3. \Wiley lJ: The mechanism of tarso-lnetatalsal joint osteoto- my. .[ Am Poclian' lled Assoc 76:324, 7986. injuries. J Bone.Joint Surg i3B:474, 7977. Scurran BL (ed): l'oot and Ankle Trauma. New' York. Churchill Livingstone, pp. 323-376, 1c)89 ADDITIONAL REFERENCES Seitz \ff'H, Grantham SA: The Jones' fracture in the non zrth- lete . Foot Ankle 6:97. 7985. Anclerson LD: Injuries of the forefoot, Clin Ofihop 722:18. Spector FL, Karlin JM, Scurran BL. Silr,ani SL: Lesser 1977. metatarsal fractures: inciclence, management. anci Bolognini N. Goldman F: N{anagement of major forefoot revierv. J Am Podiatry Assoc 74:2i9, 1981. trauma. J Fclot Surg 2,i:88, 1985. Tabak B, Lefkorvitz H. Steiner I: Nlctatarsal-slide lengtirening Dameron T: Fractures and anatomical variations of the proxi- rvrthout bone graiting. ./ Fctot Snrg 25:50, 1986. rnal portion ol the flfth lnetatarsal. Bone Sttr,q J Joint Torg JS, Balcluini IrC, Zelko RR. Paulov H, Peff TC, I)as N'1: 57A:788, 1975, Fractures of the base of the fifth metatarsal distal to the Donovan TA, Black pedal stress fracture u,-ith occupa JR: tuber

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