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182 April 2002 • Vol 92 • No 4 • Journal of the American Podiatric Medical Association

Painful instability of the lesser metatarsophalangealjoint has been recognized in both the orthopedic andthe podiatric literature as a common cause of meta-tarsalgia.1-6 The condition is typically described as aprogressive, painful subluxation or dislocation of theproximal phalangeal base on the metatarsal headthat occurs as a result of weakening of the periarticu-lar structures that stabilize the metatarsophalangealjoint—in particular, the plantar plate. The subluxa-tion/dislocation process can be slow or rapidly pro-gressive. Medial or, less commonly, lateral deviationof the digit may also occur and accompanies dorsal

migration of the proximal phalanx. A hammer toe de-formity may be found in association with the disor-der, but is usually not an early or a significant com-ponent. Unlike in the classic hammer toe deformity,a dorsal corn overlying the proximal interphalangealjoint is typically not observed (Fig. 1). Although anylesser metatarsophalangeal joint can be affected, thesecond metatarsophalangeal joint is affected mostoften.7, 8 Hallux valgus and first-ray insufficiency maycontribute to this problem but are not necessarilyprecursors or prerequisites.1-6 A long second metatar-sal has also been implicated in the development ofthis entity.1

While pain about any lesser metatarsophalangealjoint may be associated with several systemic andlocal processes, the idea of idiopathic pain and insta-bility of the metatarsophalangeal joint is relativelynew.6, 9 The literature is replete with numerous termsdescribing the components of lesser toe derangement.The following terms, for example, are slightly modi-fied from a list appearing in Miller10:

� Sub–metatarsal 2/neuroma syndrome� Chronic lesser metatarsophalangeal dislocation

Predislocation SyndromeProgressive Subluxation/Dislocation of the Lesser Metatarsophalangeal Joint

Gerard V. Yu, DPM*Molly S. Judge, DPM†

Justin R. Hudson, DPM‡Frank E. Seidelmann, DO‡

Progressive subluxation/dislocation of the lesser toes resulting from idio-pathic inflammation about one or more of the lesser metatarsophalangealjoints is a common cause of metatarsalgia that is frequently unrecognizedor misdiagnosed. The disorder results from a failure of the plantar plateand collateral ligaments that stabilize the metatarsophalangeal jointsand is typically associated with abnormal forefoot loading patterns. Theauthors refer to this condition as predislocation syndrome and have de-vised a clinical staging system that is based on the clinical signs andsymptoms present during examination. A thorough review of predisloca-tion syndrome and an overview of the conservative and surgical treat-ment options available for this disorder are presented. (J Am PodiatrMed Assoc 92(4): 182-199, 2002)

*Diplomate, American Board of Podiatric Surgery; Fel-low, American College of Foot and Ankle Surgeons; Direc-tor of Podiatric Medical Education and Residency Training,St Vincent Charity Hospital, Cleveland, OH; Faculty Mem-ber, The Podiatry Institute, Tucker, GA. Mailing address:

23823 Lorain Rd, Ste 280, North Olmstead, OH 44070.†Director of Externship Program, St Vincent Charity Hos-

pital, Cleveland, OH; private practice, Toledo, OH.‡Submitted during third-year podiatric surgical residency,

St Vincent Charity Hospital, Cleveland, OH.‡Adjunct Professor of Radiology, Ohio College of Podi-

atric Medicine, Cleveland; Clinical Professor of Radiology,Ohio University, Athens; private practice, Cleveland, OH.

Journal of the American Podiatric Medical Association • Vol 92 • No 4 • April 2002 183

� Floating toe syndrome� Lesser metatarsophalangeal joint instability syn-

drome � Second metatarsophalangeal joint dislocation/

subluxation� Monoarticular nontraumatic synovitis of the sec-

ond metatarsophalangeal joint � Crossover second-toe deformity � Second metatarsophalangeal joint instability

The authors, however, consider many of these tobe part of a distinct clinical entity, which they refer toas predislocation syndrome. Once a frank dislocationoccurs, more appropriate descriptive terminologyshould be employed. This article presents the naturalhistory of predislocation syndrome and reviews theconservative and surgical treatment options availablefor this disorder.

Clinical Presentation

Patients suffering from predislocation syndrome typ-ically present with acute, subacute, or, less common-ly, chronic focal pain at the plantar aspect of the in-volved lesser metatarsophalangeal joint or joints. Ingeneral, pain is most noticeable during ambulationand subsides during rest.11 Frequently, patients com-

plain that they feel as if they are walking on a “stonebruise” or “lump” on the bottom of the foot in spiteof the absence of any obvious plantar lesion. Patientsmay also complain of swelling about the base of thetoe, more impressive plantarly than dorsally. Somepatients will note that the toe “feels as though it istrying to go out of position,” and others may haveeven noted a distinct change in position over thecourse of several weeks. Rarely is a lesion presentover the dorsal aspect of the proximal interphalange-al joint, although mild erythema may be present as aresult of shoe irritation of the knuckle pad. Tylomaformation plantarly is rarely present.

Some patients mention a recent increase or changein activity level prior to the development of symp-toms.1 The current authors have seen this problemdevelop following participation in such activities asjogging, tennis, and basketball. In other cases, pa-tients may recall a minor traumatic event, such as amisstep on a stair, hole, or protruding object such asa garden hose or an electrical cord prior to the devel-opment of symptoms. In a number of cases, the se-nior author (G.V.Y.) has encountered a history of amisstep climbing up or down stairs or a ladder as aninciting factor.

In later stages of predislocation syndrome, severepain may lead to an antalgic gait, with the patientcompensating by walking on the lateral aspect of thefoot. Barefoot weightbearing often becomes intolera-ble, especially on hard surfaces. The authors havefound that secondary manifestations, such as lateralcolumn overload and calcaneocuboid joint syndrome,may occur, sometimes becoming as significant as theoriginal chief presenting complaint. A constant lin-gering or long-lasting throbbing sensation may alsodevelop, regardless of weightbearing status.

Frequently, the patient had sought treatment forthe problem in the past, often after being treated by avariety of medical and surgical specialists to no avail.Treatments may have been either conservative orsurgical. It is not uncommon for the patient to havereceived a diagnosis of second interspace or adjacentinterspace neuromas in spite of the obvious absenceof the subjective complaints classically associatedwith neuromas. Many patients will have undergoneneurectomy, some with revisional procedures under-taken for the presumed recurrence of neuroma orstump neuroma (Fig. 2). The failure of these varioustreatments and continuing disability are very frustrat-ing for patients and may give rise to anxiety abouttheir prognosis.6 Some patients may have been ac-cused of malingering or suspected of having a psy-chosomatic illness. A few patients or their spousesmay even question whether they are imagining the

Figure 1. Classic hammer toe deformity of the secondtoe with chronic metatarsophalangeal joint subluxa-tion. Note the presence of a classic heloma durumoverlying the proximal interphalangeal joint, which isnot typically seen in patients with predislocation syn-drome.


problem and feel as if they are acting like hypochon-driacs. Some patients, out of desperation, will plead,“Please tell me I’m not crazy!” Not uncommonly, thisunfortunate chain of events results in significant de-pression and anxiety, further complicating the clini-cal course of the complaint.

Physical Examination

Specific and accurate pain localization during a phys-ical examination is paramount for determining thestructures affected. On physical examination of thepatient with predislocation syndrome, one finds ex-cruciating pain on palpation just distal and plantar tothe metatarsal head that is disproportionate to anyother objective clinical findings. Focal pain in thisarea is thought to result from bursitis or inflamma-tion of the plantar plate.12 Occasionally, inflammationof an intermetatarsal bursa may cause local nerve ir-ritation, resulting in neuritic or neuroma-type symp-toms. However, patients presenting with pain causedby inflammation of the plantar plate generally do nothave subjective complaints of numbness or shootingpain or objective sensory deficits in the affected dig-its on clinical examination.11 In addition, on physical

examination, the focal point of tenderness is clearlyand distinctly the metatarsophalangeal joint area, notthe adjacent interspace. An intermetatarsal injectionof local anesthetic may be helpful when symptomsare generalized or when the patient has difficulty pin-pointing the target area of pain.

Active flexor and extensor tendon functions of theaffected toe are present with minimal or no compro-mise. Palpation and range of motion of the metatar-sophalangeal joint may elicit capsular crepitus ormobility of a well-circumscribed, bursa-like projec-tion. A painful decrease in range of motion of thejoint, particularly in plantarflexion, is often noted.13

Significant malposition is absent in the early stages;however, the astute clinician readily notes subtlechanges in position over time. Not uncommonly, thetoe manifests a clear tendency toward dorsal migra-tion (not necessarily dorsiflexion), with or withouttransverse plane deviation toward or away from thehallux (Fig. 3).

In most cases, evaluation of weightbearing stancedemonstrates subtle but obvious malalignment of theinvolved digit. Loss of toe purchase, with or withoutmedial or lateral deviation, is typically present. If thiscondition is left unchecked, the toe will continue toprogressively subluxate dorsally, and when this oc-curs, increased pain plantarly is predictable. Rarely,a callus plantar to the metatarsal head or a corn over-lying the proximal interphalangeal joint of the affect-ed toe (as is typically seen with the classic hammertoe deformity that has undergone chronic metatarso-phalangeal joint subluxation/dislocation) is presenton examination. These keratoses are due to frictionand shear of associated osseous structures and toloss of intrinsic muscle balance; they develop onlyafter long-standing dislocation of the toe.

Change in local topography is common and oftenimpressive (Fig. 4). Local edema and warmth result-ing from inflammation about the metatarsophalangealjoint are typically present; the increased temperaturemay be measured with skin-surface thermometersand recorded. Subtle edema may be indicated by theobliteration of normal extensor tendon contours. Inmost cases, the plantar edema is obvious, even pro-found, and encompasses the entire metatarsophalan-geal joint area, frequently extending distally into thesulcus and base of the toe or toes.

In the initial stages of predislocation syndrome,the lesser metatarsophalangeal joint may be in goodanatomical position without malalignment or con-tracture. However, as the condition progresses andjoint instability ensues, dorsal or transverse plane de-viation develops, with subsequent loss of toe pur-chase. The stages of predislocation syndrome have

Figure 2. Foot of a 45-year-old patient who previouslyunderwent two neuroma resections from the secondinterspace within a 3-month period. This patient sub-sequently developed complete dislocation of the sec-ond metatarsophalangeal joint. Note the persistentswelling of the second metatarsophalangeal joint andtoe. The patient denied having had the symptoms at-tributable to a typical neuroma.


been described by Yu and Judge6 and are based onthe clinical findings present at the time of examina-tion. In stage 1, there is mild edema plantar, and oftendorsal, to the metatarsophalangeal joint. Extremetenderness is present when the joint is manipulated.No anatomical malalignment is noted clinically. Instage 2, there is moderate edema with noticeable de-viation of the affected digit both clinically and radio-graphically. Often the patient does not realize thatthe affected toe does not purchase the ground. Thisbecomes quite evident in stance evaluation. In stage3, moderate edema is present about the entire cir-cumference of the metatarsophalangeal joint and ex-

tends into the toe. More pronounced deviation andpossible subluxation/dislocation of the toe are pres-ent. While the edema and inflammation eventuallysubside altogether, the deformity remains unchangedor continues to progress. The end result can be acrossover second-toe deformity, with or without aconcomitant hallux abducto valgus deformity.

Thompson and Hamilton5 have suggested the useof a vertical stress test, akin to the anterior drawersign in the unstable ankle joint, to identify and stagesagittal plane metatarsophalangeal joint instability.In this maneuver, the foot is placed in neutral posi-tion, and the metatarsal head is stabilized betweenthe examiner’s thumb and index finger. The con-tralateral hand is used to grip the dorsal and plantaraspect of the corresponding proximal phalanx base.The digit to be tested is manipulated upward withvertical pressure applied by the thumb plantarly. Apurely vertical force is applied to the base of theproximal phalanx in the dorsal direction. This is dif-ferent from testing for dorsiflexion (Fig. 5). A posi-tive vertical stress test result is present when theproximal phalanx can be translocated 2 mm dorsallyabove the metatarsal head. According to Thompsonand Hamilton’s classification scheme, in stage 0 thereis no dorsal translocation of the proximal phalanx. Instage 1, the phalangeal base can undergo subluxationdorsally but not dislocation. In stage 2, the pha-langeal base can be dislocated but may be manuallyreduced. In stage 3, the phalangeal base is in a fixeddislocated position. Accurate assessment of theamount of dislocation of the base of the proximalphalanx on the metatarsal head may be quantified ona lateral x-ray.

Figure 3. Nonweightbearing (A) and weightbearing (B) views of a patient with predislocation syndrome of the rightsecond toe. Note the edema surrounding the metatarsophalangeal joint, obliteration of the extensor tendons to thesecond digit, and the absence of a significant lesion over the proximal interphalangeal joint. Mild irritation is pres-ent. Absence of toe purchase and medial deviation are seen on weightbearing.

A B

Figure 4. Edema in a patient with predislocation syn-drome of the left third metatarsophalangeal joint. Thepatient has a congenital syndactyly of the second andthird digits, confusing the clinical presentation. Notethe absence of similar findings in the contralateral foot.


ond metatarsal (or a short first metatarsal) may alternormal forefoot loading patterns by transferring loadfrom the first to the second metatarsal head (Fig. 6).Hallux abducto valgus may also cause abnormalforefoot loading patterns.2 Lateral deviation of thehallux into the second digit may cause multiplanardeviation of the second toe that results in retrogradebuckling at the second metatarsophalangeal jointlevel on weightbearing. The use of high-heeled shoesor heel lifts, which increase forefoot loading by main-taining the metatarsophalangeal joints in a hyperex-tended position, have also been implicated in the de-velopment of predislocation syndrome in one ormore of the lesser digits.1

Biomechanical hypermobility may also predisposea patient to altered forefoot loading patterns. Exces-sive pronation will alter the axis of insertion of theperoneus longus tendon in such a way that it loses itsability to stabilize the first ray during the forefoot-loading phase of gait.13 Accordingly, metatarsusprimus elevatus resulting from either biomechanicaldysfunction or structural deformity may cause exces-sive load transfer to the adjacent lesser metatarso-phalangeal joint or joints. Similarly, first-ray insuffi-ciency caused by generalized joint hypermobilitysyndromes, such as Ehlers-Danlos syndrome or Mar-fan syndrome, may result in overload of one or moreof the lesser metatarsophalangeal joints.14

The senior author has also witnessed numerouscases of predislocation syndrome in patients whohad undergone surgical correction of hallux abductovalgus deformity in which subtle, but discernible, ele-vation of the first metatarsal head occurred (Fig. 7).In other cases, the initial presenting complaint wassub–metatarsal 2 discomfort attributed to an asymp-tomatic hallux abducto valgus deformity. Whilesurgery for the hallux abducto valgus was unevent-ful, progressive dislocation of the second toe ensued.Patient frustration in such cases is very high.

Coughlin1 has identified two distinct populationsat risk for developing instability of the second meta-tarsophalangeal joint: The first group consisted main-ly of sedentary women aged 50 to 70 years, with anaverage age of 60 years. The high proportion of elder-ly women in this group was attributed to the preva-lent use of high-heeled shoes in this population. Thesecond group consisted predominantly of athleticmen aged 25 to 64 years, with an average age of 50years. A majority of this group were found to have along second metatarsal. Coughlin hypothesized thatin the second group repetitive physical activity re-sulted in inflammation about the second metatarso-phalangeal joint that eventually resulted in a weaken-ing of the periarticular structures that stabilize the

A thorough history and physical examination arerequired to rule out all systemic and local problemsthat may contribute to pain about the metatarsopha-langeal joint. Degenerative joint disease, avascularnecrosis, rheumatoid arthritis, fat pad atrophy, stressfracture, neuromuscular dysfunction, and neuromasare all common causes of lesser metatarsalgia.2, 12

Only after a detailed history and physical examina-tion and a radiographic evaluation can a primary di-agnosis of predislocation syndrome be made (Table1). Selective laboratory testing may be needed forcompleteness. It is important to listen carefully to thepatient’s subjective complaints, as these will oftenprovide sufficient information for the clinician to sus-pect this entity as the cause of the patient’s pain,even prior to a physical examination of the area.

Pathomechanics

The key developmental factor for idiopathic subluxa-tion/dislocation of the lesser toe is progressive in-flammation about the metatarsophalangeal joint withsubsequent attenuation and rupture of the plantarplate and collateral ligaments.2, 5 Thus any structuralor biomechanical deformity that increases loadingforces within the forefoot and results in inflamma-tion of the plantar plate can predispose an individualto progressive weakening of the periarticular struc-tures and resultant joint instability.

A long second metatarsal is often cited as a com-mon finding in individuals with instability of the sec-ond metatarsophalangeal joint.8, 11 An elongated sec-

Figure 5. Positive vertical stress test result with dor-sal translocation of the proximal phalanx. Note main-tenance of the toe parallel to the plantar aspect of thefoot while this maneuver is performed. The examinermust be careful not to confuse dorsal translocationwith dorsiflexion.


Table 1. Differentiating Predislocation Syndrome from Common Lesser Metatarsophalangeal Joint Problems

Predislocation Syndrome Other Common Problems

Stress FracturePain localized to plantar metatarsophalangeal joint Pain at metatarsal shaft dorsallyNegative tuning fork test Tuning fork test elicits painX-rays nondiagnostic in early stages Conventional x-rays eventually diagnosticBone scan uptake at metatarsophalangeal joint Bone scan uptake in metatarsal shaft

Hammer ToeMinor trauma or inciting event may be recalled No inciting event or traumaOnset distinctly acute, subacute, or chronic Onset insidious over yearsNo digital contracture until late stage Contracture at proximal or distal interphalangeal joint

preceded painPositive vertical drawer test Negative vertical drawer testUsually no lesions; occasional irritation of the dorsal Lesions frequently present: heloma durum at proximal

proximal interphalangeal joint interphalangeal joint and/or sub–metatarsal head tyloma

NeuromaPlantar to metatarsophalangeal joint, often the second Classic third interspace

interspaceNeuritic symptoms absent Neuritic symptoms: tingling, cramping, burning, shooting painMoulder sign absent Positive Moulder sign: palpable click of soft-tissue massSubtle or obvious malalignment or malposition of the Toes usually have normal alignment and position

involved toesMay demonstrate significant inflammation of No edema present

metatarsophalangeal joint and toe, especially plantarly

Figure 6. Anteroposterior (A) and lateral (B) radiographs of a patient who developed sudden dislocation of thesecond metatarsophalangeal joint following a period of severe pain and inflammation of the plantar aspect of thejoint. Note the slightly elongated second metatarsal segment as a possible contributing factor and the presence ofa hallux abducto valgus deformity.

A B


toe. The authors believe that both structural alter-ation and biomechanical dysfunction of the first raycan contribute to the development of this entity atthe second metatarsophalangeal joint. The conditioncan, however, occur in the absence of either of thesepredisposing factors.

Role of the Plantar Plate in Predislocation Syndrome

Stability of the lesser metatarsophalangeal joint isderived from the plantar plate, the collateral liga-ments, and the intrinsic and extrinsic foot muscula-ture.15-17 Static stabilization of the metatarsophalan-geal joint is derived primarily from the plantar plateand collateral ligaments. The plantar plate is de-scribed as a fibrocartilaginous thickening of themetatarsophalangeal joint capsule plantarly that isfirmly attached to the base of the proximal phalanxbut only loosely attached to the metatarsal head.15 Itis composed of type I collagen that is histologicallyidentical to the collagen present in the meniscus ofthe knee.16 The plantar plate acts as the major distalattachment of the plantar fascia and has attachmentsto the deep transverse metatarsal ligament andmetatarsophalangeal joint collateral ligaments. It

also serves as an insertion for both the interosseousand the lumbrical tendons. Inferiorly, the plantarplate has a smooth grooved surface for the passageof the flexor tendons.

An anatomical dissection by Johnston et al15

demonstrated that the plantar plate of the foot is sim-ilar in both form and function to the volar plate ofthe hand. However, those authors noted that theplantar plate is larger and thicker than the volar plateand has a weaker proximal attachment. Deland et al16

also performed an in-depth anatomical dissection ofthe plantar plate and outlined several possible func-tions of the structure. First, the plantar plate mergeswith the plantar fascia distally and is an integral partof the windlass mechanism. Second, its fibrocarti-laginous structure helps to absorb compressive loadsacting on the metatarsal head. Finally, its central posi-tion and multiple attachments act to stabilize the less-er metatarsophalangeal joint in the plantar direction.

Through mechanical testing, Bhatia et al17 foundthe plantar plate to be the main stabilizing force ofthe metatarsophalangeal joint. The study concludedthat the metatarsophalangeal joint collateral liga-ments, which have an insertion into the plantar plate,are the second most powerful structures that stabi-lize the metatarsophalangeal joint. Deland and Sung18

Figure 7. Anteroposterior (A) and lateral (B) radiographs demonstrating dorsal dislocation of the second toe followinga distal metaphyseal osteotomy for correction of a hallux abducto valgus deformity. The patient’s initial complaint waspain beneath the second metatarsal segment. An arthroplasty procedure was performed. Owing to persistent symp-toms, the patient received multiple injections of steroid and local anesthetic, which resulted in acceleration of the de-formity and a steroid-induced avascular necrosis of the third proximal phalangeal base. Note the development of astress fracture of the second metatarsal and the shortening and elevation of the first metatarsal segment.

A B


performed an anatomical dissection of a medial cross-over second toe in a cadaveric specimen in an attemptto fully describe the underlying pathologic anatomyfound in the condition. The specimen exhibited rup-ture of the lateral collateral ligaments, shortening ofthe medial collateral ligaments, attenuation of theplantar plate, and dorsal medial displacement of boththe flexor tendons and the plantar plate.

While static stabilization of the metatarsophalan-geal joint is primarily the function of the plantarplate, dynamic stabilization is provided by the extrin-sic and intrinsic musculature of the foot. It should benoted, however, that the ability of the intrinsic andextrinsic foot musculature to stabilize this joint is de-pendent largely on the integrity of the plantar plate.When the metatarsophalangeal joint is in a flexed orneutral position, the extensor digitorum longus andextensor digitorum brevis tendons act to dorsiflexthe metatarsophalangeal joint through their insertioninto the extensor hood apparatus.19 However, withrupture of the plantar plate, the proximal phalanx as-sumes a subluxated (dorsal) position, and the exten-sor tendons are mechanically unable to extend theproximal and distal interphalangeal joints. When themetatarsophalangeal joint is maintained in a sublux-ated (dorsal) position for a prolonged period, the ex-tensor digitorum longus becomes a deforming forceat the metatarsophalangeal joint and results in pro-gressive dorsal subluxation and frank dislocation ofthe toe.2

The flexor digitorum longus and brevis tendonsprovide flexion at the proximal and distal interpha-langeal joints, but are relatively inefficient flexors ofthe metatarsophalangeal joint.3 In a weightbearing sit-uation, these muscles act to stabilize the toes againstthe ground and, in doing so, may cause slight dorsi-flexion of the metatarsophalangeal joint.19 The flexortendons are therefore unable to aid in stabilization ofthe dorsally subluxated toe.

Under normal circumstances, the interosseousmuscles provide most of the flexion that occurs atthe lesser metatarsophalangeal joints.20 However,with dorsal subluxation of the metatarsophalangealjoint, the interosseous tendons migrate dorsal to theaxis of the metatarsophalangeal joint and subse-quently lose their mechanical ability to provide flex-ion of the joint.21 The lumbrical muscles also play animportant role in the dynamic stability of the lessermetatarsophalangeal joint. These muscles arise fromthe long flexor tendons and insert into the medial as-pect of the extensor hood. According to an anatomi-cal and functional study performed by Jarrett et al,22

the interosseous muscles stabilize the interphalange-al joints in the extended position and maintain the

metatarsophalangeal joint in the plantarflexed posi-tion during weightbearing. However, like the interos-seous muscles, they too lose their ability to provideflexion of the metatarsophalangeal joint when theproximal phalanx is in a subluxated (dorsal) posi-tion.3 Thus, in chronic subluxation of the metatarso-phalangeal joint, the long and short flexor, interosse-ous, and lumbrical muscles provide no dynamicrestraint to dorsal dislocation of the toe.

The second toe is anatomically unique, having in-sertions of two dorsal interosseous tendons but noplantar interosseous tendon. The lumbrical tendonhas a medial insertion and provides a slight medialpull in the second toe. With chronic inflammationabout the metatarsophalangeal joint, progressivedorsal subluxation of the second toe ensues as theplantar plate and collateral ligaments fail in staticstabilization of the joint. As a result of the dorsal po-sition of the toe, the normal axes of the intrinsic mus-cles are lost, rendering them incapable of dynamical-ly stabilizing the joint. The extensor digitorum longusand lumbrical muscles subsequently become a de-forming force, contributing to dorsal medial disloca-tion of the toe.

Further explanation for a dorsal medial disloca-tion following failure of the plantar plate has beenprovided by Hatch and Burns,23 who performed ananatomical dissection of seven cadaveric specimensexhibiting a crossover second-toe deformity. The au-thors found that four of the seven specimens demon-strated an accessory medial slip of the extensor digi-torum brevis tendon to the second toe and believedthat this accessory tendon was a contributing factorin the etiology of the crossover second-toe deformi-ty. The current authors have not found this anatomi-cal variant in several cases of predislocation syn-drome that have undergone surgical correction.

Anatomically, it is easy to understand why dorsalmedial dislocations are most common at the secondmetatarsophalangeal joint. However, dorsal medialdislocations are also more common than dorsal later-al dislocations at the other lesser metatarsophalange-al joints. The rationale behind this observation is noteasily understood, as the other lesser metatarsophalan-geal joints have both dorsal and plantar interosseoustendon insertions that directly oppose one another inthe transverse plane. Subluxation and dislocation ofthe lesser toe at the level of the lesser metatarsopha-langeal joint, not attributable to the normal progres-sion of the classic hammer toe deformity, are stillsomewhat of an enigma and continue to challengephysicians who treat foot and ankle problems. Thesenior author has diagnosed and treated predisloca-tion syndrome involving one or more of the following


digits: second, third, and fourth (Fig. 8). While dorsalsubluxation is seen in all of them, the medial or later-al deviation is a peculiar finding not well understood.The authors suggest that an underlying structuralmetatarsus adductus deformity may influence thetype of transverse plane deformity that develops.

Diagnostic Modalities

Several imaging modalities are available to assess in-stability of the lesser metatarsophalangeal joint, al-though rarely is extensive or expensive imaging re-quired. When there is clinical evidence of subluxationor dislocation, standard radiography is the mostpractical diagnostic modality and is essential in rul-ing out local or systemic pathologies that contributeto lesser metatarsophalangeal joint instability and

dysfunction. Weightbearing lateral or oblique radio-graphs clearly indicate dorsal subluxation of theproximal phalanx upon the metatarsal head as thecondition progresses. Weightbearing anteroposteriorradiographs will demonstrate dorsal as well as trans-verse deviation of the affected toe. The normal clearspace of the lesser metatarsophalangeal joint is 2 to 3mm, and the joint surfaces should be congruent.2

When dorsal subluxation or dislocation is present,the clear space is obliterated as the concave base ofthe proximal phalanx migrates dorsally over the con-vex metatarsal head. Incongruency of the joint spaceis noticed as the digit deviates in the sagittal andtransverse planes. The anteroposterior radiographwill also demonstrate any abnormal metatarsallength patterns that might contribute to the develop-ment and progression of this deformity. Cortical hy-

Figure 8. Predislocation syndrome of the third metatar-sophalangeal joint. A, Initial radiographic findings wereunremarkable; B, a subsequent radiograph demon-strated a complete dislocation of the third metatarso-phalangeal joint (arrow); C, note the swelling of thedigit and corresponding metatarsophalangeal joint.

A B

C


pertrophy of the affected metatarsal shaft may bepresent and is believed to be indicative of abnormalforefoot loading.1 However, the authors have notfound this to be a consistent finding. Finally, a radio-graphic vertical stress test may also be used to sup-port the clinical findings of sagittal plane instability.

More advanced imaging modalities may be war-ranted when there is no clear clinical or radiographicevidence of instability. An arthrogram with 0.5 to 1mL of iodinated contrast material injected dorsallyinto the metatarsophalangeal joint under fluoroscopymay be used to evaluate the integrity of the metatar-sophalangeal joint capsule.24 Rupture of the metatar-sophalangeal joint capsule is demonstrated by opaci-fication of the flexor tendon sheath while leakage ofthe contrast material outside the joint capsule intothe intermetatarsal bursa is indicative of collateralligament rupture.25

Although not typically used, a nuclear medicinethree-phase bone scan will show increased tracer up-take at the metatarsophalangeal joint during all threephases.6, 11 The first two phases are decidedly moreintense than the delayed phase. This pattern stronglysuggests a local inflammatory process, rather than anosseous problem. Additionally, a conventional bonescan may be helpful in identifying a stress fracturenot identified on conventional radiographs. The pat-tern of uptake is different from that seen in patientswith predislocation syndrome. A stress fracturewould show increased uptake in all phases of thebone scan with the greatest uptake in the delayedphase (3 to 6 hours), which demonstrates a linearpattern within the shaft of the affected metatarsal. Incontrast, the pattern of uptake in patients with pre-dislocation syndrome is localized to the metatarso-phalangeal joint area.

Magnetic resonance imaging (MRI) of the mani-festations of predislocation syndrome can be demon-strated on high-field, as well as low-field, magnets.This includes imaging on high-field superconductingextremity images. However, adequate MRI visualiza-tion demands a tailored approach. The necessarypulse sequences include sagittal longitudinal relax-ation time (sagittal T1), gradient echo transverse re-laxation time (gradient echo T2), and short tau inver-sion recovery (STIR) images and coronal T1 andSTIR images, as well as an oblique axial STIR se-quence for imaging of the metatarsals and intrinsicmuscles of the forefoot.

The selection of pulse sequences is very impor-tant. Sagittal images are obtained perpendicular tothe long axis of the metatarsals. Coronal images,however, require alignment of the first and secondmetatarsal heads, with imaging of the lesser metatar-

sophalangeal joints obtained parallel to the secondthrough fifth metatarsal heads. The oblique axial se-quence is aligned to the dorsal surface of the footwith a lateral down-sloping orientation. To obtain thescan, merely instruct the technologists to perform aSTIR sequence in the plane defined by laying theirhand on the dorsum of the forefoot region. This com-bination of pulse sequences provides a simple yet de-tailed evaluation of the metatarsophalangeal jointsand their associated capsuloligamentous complexes,including the plantar plate.

The plantar plate and its associated structures arebest visualized on T1 and gradient echo image se-quences.25 In T1-weighted images, the plantar plate isseen as a smooth, low-signal structure running be-neath the metatarsal head and proximal phalangealbase. However, the plantar plate may be difficult todistinguish from the thicker, underlying flexor ten-dons on T1-weighted images. For this reason, it ishelpful to obtain gradient echo images in which theplantar plate is slightly hyperintense relative to theflexor tendons.

The MRI findings of plantar plate rupture havebeen well documented by Yao et al.25, 26 A rupture ofthe plantar plate will demonstrate increased signalintensity within the plate with a loss of continuity.26

The area of rupture will be isointense with synoviumand joint fluid and is typically located adjacent to themetatarsal head (Fig. 9). Synovitis of the flexor ten-don sheath and distention of the metatarsophalange-al joint capsule are common associated findings inplantar plate rupture and, if present, are readily iden-tified on MRI.

Figure 9. Typical MRI findings of a patient with pre-dislocation syndrome involving the second and thirdmetatarsophalangeal joints.


Conservative Treatment

The goal of conservative treatment for predislocationsyndrome is to prevent progression of the deformityand alleviate symptoms. Successful treatment is mostoften accomplished with a combination of severaltreatment modalities. Nonsteroidal anti-inflammatorydrugs and corticosteroids have been a mainstay forthe management of the pain and inflammation associ-ated with this disorder. While a tapered course oforal corticosteroids has been found to be safe and ef-fective, the same cannot be said about repeatedintra-articular steroid injections. Dislocation of thetoe following repeated intra-articular administrationof corticosteroids has been documented in the litera-ture.27 The senior author has witnessed this in sever-al cases where dislocation of the metatarsophalange-al joint was seemingly accentuated by the repeateduse of intra-articular steroid injection.

The adverse effects of corticosteroid injection di-rectly into periarticular structures have been record-ed in the literature. In one study, a single injection ofmethylprednisone (4 mg) deposited directly into liga-mentous tissues destroyed fibrocytes and decreasedthe tensile strength of the tissues for as long as 1year.28 The physician must realize that such an injec-tion may weaken the already compromised plantarplate. However, if intra-articular steroids are deemednecessary, the smallest effective dose of a phosphatesalt should be used. Generally accepted guidelinesrecommend that any given joint be injected a maxi-mum of once every 1 to 3 months and no more thantwo to three times within a 12-month period.29 Anumber of factors will influence the frequency of in-jections; these include the type of steroid, the quanti-ty of the steroid, and the clinical entity being treated.The authors strongly discourage the indiscriminate,repeated use of intra-articular steroids for predislo-cation syndrome. In the authors’ opinion, the use ofacetate steroids is rarely, if ever, indicated for thetreatment of predislocation syndrome. If intra-articu-lar steroids are employed, splinting of the toe tomaintain position and prevent progressive disloca-tion is strongly recommended.

In addition to pharmacologic therapy, offloadingthe metatarsophalangeal joint and supporting the toein a proper position are essential to successful treat-ment. Taping of the digit into a slightly overcorrectedrectus position can prevent pain and progression ofthe deformity. It is believed that this course of treat-ment stabilizes the digit enough to allow fibrosis ofthe periarticular structures to occur. However, thereare two main drawbacks to taping of the digit: 1)Taping may take several months before stability and

pain-free ambulation are achieved; 2) a prolongedcourse of taping may result in edema and possible ul-ceration of the digit.11 In short, it is simply not practi-cal. Taping is, however, useful in helping to establishthe diagnosis of predislocation syndrome at the ini-tial office visit, provided that the metatarsophalange-al joint has undergone only deviation or subluxation,not dislocation. Taping the toe in the correct positionoften provides immediate relief of the patient’s symp-toms on weightbearing, confirming the diagnosis ofpredislocation syndrome.

Splinting may also be used to maintain proper ana-tomical alignment of the digit. A metatarsal sling padstabilizes the proximal phalanx in a plantar directionat the metatarsophalangeal joint level by augmentingthe function of the plantar plate and preventing hy-perextension or dorsal migration of the proximalphalanx. Accommodative padding may also be usedto alleviate symptoms at the affected metatarsopha-langeal joint. A longitudinal metatarsal pad with alesser metatarsophalangeal joint cutout can be usedto effectively decrease the weightbearing stress onthe metatarsal head. A metatarsal pad applied to thefoot or used in the shoe is also helpful, but far less ef-fective than the metatarsal sling pad. It will offloadthe metatarsal but is insufficient in providing directsplinting of the toe in a plantar direction and fails toprevent further dorsal migration and dislocation.

For patients who have received insufficient bene-fit from taping and padding therapy or are not con-sidered candidates for surgery, shoe modificationsmay relieve symptoms.3-5, 30 An extra-depth shoe toaccommodate the digital deformity combined with arocker-bottom sole with steel shank to decreasepropulsive forces on the affected metatarsophalange-al joint may be effective. A viable alternative optionfor treating this condition is an extra-depth shoe witha metatarsal bar added to the sole.

The authors’ typical regimen for the conservativetreatment of predislocation syndrome consists of acombination of oral steroids, nonsteroidal anti-in-flammatory drugs, and taping or padding. In cases ofsignificant symptomatology associated with moder-ate to severe inflammation, oral steroids have beenvery effective. The authors typically use a taperingdose (from 60 to 10 mg in 10-mg increments) of pred-nisone, administered in twenty-one 10-mg tablets;this regimen is extremely effective clinically andquite cost-effective. This is followed by a course ofnonsteroidal anti-inflammatory drug therapy in con-junction with splinting. Additionally, the authorsoften employ physical therapy and aggressive manip-ulation to stretch out the dorsally contracted tissuesand decrease inflammation.


Crossover taping of the toe in proper position usu-ally provides immediate relief of symptoms in the of-fice (Fig. 10). The patient is permitted to be weight-bearing and ambulate. If the patient is comfortablewith this taping, the diagnosis is confirmed. A meta-tarsal sling pad fabricated from 1/8-inch adhesivefoam, moleskin, and tube gauze has been very effec-tive for this condition and is worn for weeks tomonths until the toe stabilizes or is corrected surgi-cally (Fig. 11). Felt should not be used to fabricatethese pads because its bulkiness aggravates plantardiscomfort and usually makes it difficult for the padsto fit into normal shoes. Foam does not seem to posethis problem. Prefabricated pads are commerciallyavailable for single-, double-, or triple-digit control.Where the toe deviates in more than one plane, it canbe splinted to the adjacent toe with a multidigit padby securing the digital straps to one another.

Varying degrees of success have been reportedwith conservative treatment of lesser metatarsopha-langeal joint instability. Mizel and Michelson4 treatedpatients with a combination of a single intracapsularsteroid injection and a laced shoe with a steel shankadded to the outer sole. They reported a 70% successrate with this treatment regimen for a 75-month fol-low-up period. Trepman and Yeo30 also used a singleintra-articular steriod injection and a rocker-soleshoe modification to treat lesser metatarsophalange-al joint synovitis. That study included 15 joints in 13patients with no known history of rheumatologicconditions. At follow-up evaluation, an average of 18months later, nine joints (60%) were asymptomatic,five joints (33%) were improved, and one joint (7%)had progressed to surgery. Mann and Mizel9 treated agroup of seven patients with nonsteroidal anti-inflam-

matory medications and extra-depth shoes with ametatarsal support. Only one patient responded posi-tively to this course of treatment; the remainder pro-gressed to surgical correction of the deformity. Cough-lin1 treated a group of ten athletes with taping for aperiod of 3 to 6 months combined with a reduction inactivity level. Three of the ten patients respondedwell to this treatment, and six of the remaining sevenpatients progressed to surgery.

One weakness of these studies is the lack of cor-relation of the stage of the deformity with the clinicaloutcome of conservative treatment. In the Coughlinstudy, all of the patients already had a positive verti-cal stress test result, and eight of the ten patients hadeither transverse or sagittal plane deviation at thetime of initial presentation. It would seem likely thatthe number of patients requiring surgical correctionwould be lower if the disorder was identified andtreated prior to obvious or frank subluxation. None-theless, the literature bears out that conservative treat-ment will only prevent progression of the deformityand does not permit realignment of the digit once sig-nificant malalignment or instability has occurred.

In the authors’ experience, significant alleviationof symptoms can be quickly achieved with conserva-tive treatment; however, the complete resolution ofall symptoms is less predictable. Digital splinting andpharmacologic management are used for severalmonths in most cases. Early discontinuation ofsplinting is likely to result in progressive subluxationand dislocation of the metatarsophalangeal joint. Asthis occurs, secondary contracture of the extensordigitorum longus tendon develops along with dorsal

Figure 10. Crossover tape used as a diagnostic toolto evaluate and assess predislocation syndrome.

Figure 11. Metatarsal pad to maintain digital positionwhen metatarsophalangeal joint dislocation has notyet occurred is shown along with the materials usedto fabricate it. The materials are 1/8-inch foam, mole-skin, and tube gauze. Prefabricated pads are readilyavailable.


contracture of the metatarsophalangeal joint cap-sule. Once flexibility and reducibility of the deformi-ty are lost, surgical intervention becomes the logicalnext treatment.

Surgical Management

In light of the frequent failure of conservative treat-ment in dealing with subluxation/dislocation of thelesser metatarsophalangeal joint, numerous surgicalprocedures have been advocated to correct the de-formity.2, 3, 9, 31-37 While there is great divergence in thestrategies employed to correct the deformity, thebasic goal of all of the procedures is release of peri-articular contractures and decompression of themetatarsophalangeal joint to reestablish alignment ofthe digit. Surgical treatment should focus on restora-tion of plantar plate function and release of the dor-sally contracted structures. The design and extent ofsurgery will vary with the severity of the deformityand the amount of time that has elapsed since the ini-tial diagnosis.

Several authors have realized the importance ofthe plantar plate and collateral ligaments in stabiliz-ing the metatarsophalangeal joint and have developedprocedures to correct the deformity at this level.Some surgeons have chosen to correct this deformitywith direct primary repair of the plantar plate. Aplantar incisional approach is employed with directvisualization of the plantar plate. The attenuated orruptured site is identified, and direct primary surgicalrepair is performed with or without concomitantarthroplasty or arthrodesis of the proximal interpha-langeal joint and release of the dorsal contracted softtissue.

Ford et al33 have also advocated primary repair ofthe plantar plate to correct this deformity. Using abiomechanical testing apparatus, they showed thatprimary plantar plate repair is as effective as a flexor-to-extensor tendon transfer in stabilizing the metatar-sophalangeal joint. However, the study concluded thatperforming both procedures together was more effec-tive than performing either procedure individually.

Deland et al32 noted the importance of the collat-eral ligaments in stabilizing the metatarsophalangealjoint and proposed grafting of a partial thickness ofthe interosseous tendon to reinforce the weakenedcollateral ligament. Although Deland et al only re-ported on the procedure as performed in cadavericspecimens, they stated that the benefits of this proce-dure would include a good range of motion postoper-atively, compared with a flexor-to-extensor tendontransfer, and the ability to control the transverseplane alignment of the digits.

Numerous authors have advocated other soft-tis-sue procedures to correct subluxation or dislocationof the lesser metatarsophalangeal joint. Ruch31 hasdescribed two different procedures in which the ex-tensor digitorum brevis tendon is transferred to re-establish muscle-tendon balance at the lesser metatar-sophalangeal joint. Girdlestone35 is often credited asbeing one of the first to advocate reduction of thedislocated metatarsophalangeal joint by splitting thelong flexor tendon and transferring it to the dorsumof the proximal phalanx. Later, Kuwada and Dock-ery38 popularized the transfer of the long flexor ten-don to the dorsal aspect of the proximal phalanxthrough a drill hole in the neck of the proximal pha-lanx. A recent modification of that procedure placesthe drill hole in the base of the proximal phalanx.39

The benefits of this modification include better re-duction of the dislocation owing to a more proximalpull of the flexor tendon and the preservation of theability to perform either a proximal interphalangealjoint arthroplasty or arthrodesis. The main drawbackof all flexor-to-extensor transfer procedures is thedecreased dorsal range of motion at the metatarso-phalangeal joint that occurs postoperatively. This,however, may also be construed as the main benefitof the procedure, as the goal of treatment is to pre-vent dorsal migration and dislocation of the toe.

Some authors have used a combination of soft-tis-sue and osseous procedures to correct the deformity.Daly and Johnson40 advocated resection of the basesof the second and third proximal phalanges withsubtotal webbing. They believed that subtotal web-bing promoted digital stability that was lost as a re-sult of the resection of the bases of the proximal pha-langes. Coughlin and Mann11 have recommendedrelocation of the metatarsophalangeal joint by partialmetatarsal head resection and release of the con-tracted periarticular structures in severe cases of dis-location of the metatarsophalangeal joint. Cracchioloet al41 reported on 28 cases in which silicone implantarthroplasty was used to correct second metatarso-phalangeal joint dislocation. They reported good re-sults in 88% of patients presenting with multiple fore-foot deformities. The authors cited transfer lesionsas the most frequent complication of the procedure.

Other osseous procedures that have been used in-clude oblique osteotomies of the head and neck ofthe metatarsal, with or without fixation. In a compar-ison of the results of the Weil and Helal osteotomiesin correcting dislocation of the lesser metatarsopha-langeal joint, Trnka et al36 concluded that the Weil os-teotomy was far superior in maintaining the metatarso-phalangeal joint in a corrected position and resultedin fewer malunions. They suggest that this is because


the Weil procedure uses stable internal fixation whilethe Helal procedure allows the metatarsal head to“float” or “seek its own level” after osteotomy. Van-deputte et al42 studied the use of the Weil osteotomyfor both intractable plantar keratosis and chronicallydislocated metatarsophalangeal joints. Of the 59metatarsophalangeal joints involved in the study, 33were chronically dislocated. At follow-up at an aver-age of 30 months postoperatively, patients rated theresults as excellent or good in 32 of 37 feet (86%).Two symptomatic transfer lesions occurred, and re-current dislocations occurred in 5 joints. Vandeputteet al concluded that the Weil osteotomy is simple andefficient for the reduction of chronically dislocatedlesser metatarsophalangeal joints.

The current authors do not have experience withdirect surgical repair of the plantar plate, but have in-stead chosen to approach this problem by means ofvarious soft-tissue and osseous procedures. A dorsalincisional approach is employed. An arthrodesis ofthe proximal interphalangeal joint is typically per-formed. The dorsal soft-tissue release is done in a se-quential manner until complete release and reloca-tion of the toe at the metatarsophalangeal joint areachieved. An extensor hood release/recession is fol-lowed by a dorsal/medial/lateral metatarsophalangealjoint capsule release. It is not uncommon for a signifi-cant amount of synovitis to be present within thejoint. Debridement of this inflammatory tissue is per-formed as needed (Figs. 12 and 13). The toe is stabi-lized with a Kirschner wire driven across the metatar-

sophalangeal joint for 5 to 7 weeks, allowing for soft-tissue adaptation and stabilization of the metatarso-phalangeal joint.

If instability of the metatarsophalangeal joint per-sists following soft-tissue release, a flexor tendontransfer employing the flexor digitorum longus (morecommonly) or the flexor digitorum brevis is stronglyrecommended (Fig. 14). Arthrodesis of the proximalinterphalangeal joint alone, although helping to cre-ate a rigid beam effect of the toe, may not be suffi-cient to prevent dorsal subluxation/dislocation of thephalangeal base.

Several types of flexor digitorum longus tendontransfers have been well described in the orthopedicand podiatric literature. Several modifications thecurrent authors employ are worthy of discussion. Re-gardless of the technique of actual transfer, the au-thors routinely harvest the tendon at the level of theproximal interphalangeal joint that is undergoingarthrodesis. The plantar tissue is incised at the baseof the middle phalanx from the dorsal incision. Asecondary plantar incision, although commonlyused, is not necessary. The split flexor digitorum bre-vis tendon is retracted medially and laterally, and theflexor digitorum longus tendon identified. The ten-don is retracted into the wound, tagged, and tran-sected at the level of the middle phalangeal base.

The tendon is transferred by means of one of sev-eral techniques. The standard technique is to split thetendon and then transfer each of the two halvesaround the proximal phalanx and suture them to-gether dorsally. Another technique is to suture theend of the tendon distally, split it proximally, andthen simply pass it over the proximal phalangeal neckarea, creating a “check-rein” type of configuration.

Figure 12. Intraoperative appearance of the secondmetatarsophalangeal joint following complete reloca-tion of the digit. Note the extensive synovitis within thejoint capsule. In addition to soft-tissue release and syn-ovectomy, an arthrodesis of the proximal interphalan-geal joint was performed.

Figure 13. Clinical photograph 6 months followingsurgery of the patient shown in Figures 2 and 12.


The authors’ current recommendation is to passthe tendon from plantar to dorsal through a drill holeat the proximal metaphyseal–diaphyseal junctionand secure it to the dorsal periosteal tissues (Figs. 15and 16). When the digit is stabilized with a Kirschnerwire, the wire is driven through the transferred flex-or digitorum longus tendon and across the lessermetatarsophalangeal joint. It is important to impart aphysiologic tension to the transferred tendon, as ex-cessive tightness can limit the amount of dorsiflexion

at the metatarsophalangeal joint that is available fornormal walking.

In more resistant and recalcitrant cases, an osteot-omy of the metatarsal for shortening or angular cor-rection will be necessary. A variety of techniques canbe performed depending on the need for, and extentof, shortening versus angular correction of the meta-tarsal segment. A through-and-through oblique oste-otomy from dorsal distal to plantar proximal allowsfor shortening as well as rotation if needed. Small

Figure 14. Traditional technique of flexor digitorumlongus tendon transfer. Tendon has been harvestedat the proximal interphalangeal joint level, split, andbrought around the diaphysis of the proximal phalanx.A simultaneous arthrodesis of the proximal interpha-langeal joint will further facilitate plantar stabilizationof the digit via the flexor digitorum longus and flexordigitorum brevis.

Figure 15. Modified technique of flexor digitorumlongus tendon transfer through a drill hole at the baseof the proximal phalanx. The tendon is sutured to thedorsal periosteum and extensor digitorum longus ten-don. Simultaneous fusion of the proximal interpha-langeal joint can be performed. As shown here, theKirschner wire is driven through the tendon and acrossthe metatarsophalangeal joint if desired.

Figure 16. Preoperative (A) and postoperative (B) clinical appearance of the patient in Figure 15 following correc-tion of the hallux abducto valgus deformity as well as arthrodesis and flexor digitorum longus tendon transfer ofthe second digit.

A B


cortical screws are used to fixate the osteotomy. Ashortening Z-osteotomy can also be employed. Ifonly angular change of the metatarsal is needed inthe transverse plane, a small wedge osteotomy at themetatarsal base can be very effective; a rotational os-teotomy can also be employed. The authors generallyreserve metatarsal osteotomy for the more severeand fixed deformity where obvious structural defor-mity (abnormal length or position) is present (Figs.17 and 18).

Conclusion

Instability of the lesser metatarsophalangeal joint isbecoming well recognized and accepted in podiatricand orthopedic surgery. It is often the sequela of achronic inflammation resulting from increased andabnormal weightbearing stresses about the lessermetatarsophalangeal joint. The end result of this de-rangement is attenuation or rupture of the plantarplate, capsule, or collateral ligaments with subse-quent subluxation or dislocation of the digit.

This clinical entity has been underrecognized as acause of lesser metatarsalgia. Although the seconddigit is most commonly and most profoundly affect-ed (ie, crossover second-toe deformity), the adjacentthird and fourth digits can also be affected. Addition-ally, one or more lesser digits can be simultaneouslyinvolved.

The clinical signs and symptoms present on exam-ination can help to stage and chart the evolution of

lesser-toe metatarsophalangeal joint subluxation/dis-location. The treatment of predislocation syndromeis dependent on the stage of the deformity. In earlypredislocation syndrome, conservative treatmentwith anti-inflammatory medication, shoe modifica-tion, padding, and taping may be successful in pre-venting progression of the deformity. In long-stand-ing deformity of the lesser metatarsophalangeal joint,surgical intervention is warranted when painful fixedsubluxation or dislocation is present and conserva-tive treatment modalities have failed or when pro-longed conservative care is not desirable.

Acknowledgment. The Podiatry Institute and At-lanta Slide Art Productions (Tucker, Georgia) for theirassistance in the preparation of the photographs;Michael Dujela, DPM, for his assistance with thepreparation of the manuscript.

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