Foot Ankle Clin N Am

The Adult Clubfoot(Congenital Pes Cavus)

Arthur K. Walling, MDFlorida Orthopaedic Institute, 13020 N. Telecom Parkway,

Temple Terrace, FL 33637, USA

Clubfoot occurs in approximately 1 of every 1000 live births, with bilat-eral deformities occurring in approximately 50% of these children [1]. Mostcases are sporadic, although families with clubfoot as an autosomal domi-nant trait with an incomplete penetrance have been reported.

Multiple theories have been proposed regarding the cause of clubfoot.One suggestion is that a primary germ plasm defect in the talus producesprogressive plantar flexion and inversion of the talus, resulting in soft tissuechanges in the joints and musculotendinous units [2]. Other theories includethe suggestion that primary soft tissue abnormalities within the neuromus-cular units produce the secondary bony changes [3] or that intrauterineenteroviral infection affects the anterior horn cells, thus producing the club-foot deformity [4]. In addition, vascular anomalies, abnormal distribution oftypes I and II muscle fibers, and muscle imbalance secondary to peripheralnerve abnormalities or spinal cord dysfunction may play important roles inclubfoot deformity [5,6].

The pathologic anatomy of the adult clubfoot residual consists of fourcomponents: cavus, adductus, varus, and equinus. Adult clubfoot residualsencountered after childhood most commonly occur because of a failure ofearlier treatment rather than from a lack of initial recognition. Treatmentfailure with casting occurs when the first ray is inadequately elevated beforeabducting the foot about the fulcrum of the talar head [7]. Improper castingtechniques may also result in a more serious deformity than residual cavuswhen the equinus deformity is inappropriately corrected while the calcaneusremains locked underneath the talus, thus dorsiflexing the foot through themidfoot rather than through the ankle, with a subsequent rocker-bottomdeformity.

13 (2008) 307–314

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Corrective surgical procedures in early clubfoot deformity have alsoturned out to be less reliable in providing lasting correction than oncethought [8]. As with casting, patients presenting with problems with a post-surgical clubfoot are as likely to have overcorrection into planovalgus as tohave undercorrection in cavovarus. Unfortunately, one common finding inthe surgically corrected clubfoot residual is a significant amount of stiffness.Specifically, late subtalar stiffness is primarily associated with a poor resultfollowing childhood clubfoot surgery [9]. This residual stiffness can signifi-cantly limit treatment options, and often leads to triple arthrodesis as theonly option for salvage.

In the rare instance where a clubfoot is not treated and is allowed toremain deformed, many late adaptive changes occur, not only in the bonesbut also in the soft tissues. These changes depend on the severity of thesoft tissue contractures and their effects on walking. The spectrum of re-sidual deformity at maturity can range from spontaneous fusion of jointsto severe degenerative changes as a consequence of these soft tissuecontractures.

The evaluation of the patient who has adult residual clubfoot is similar tothe evaluation of any other patient who has cavovarus deformity, with theexception that he/she will usually provide a history of either nonsurgical orprevious surgical treatment for the deformity.

The physical examination needs to include an evaluation of the foot andankle in the seated and weight-bearing modes and an evaluation during thewalking cycle. With the patient seated, an evaluation of active and passiverange of motion of the ankle, subtalar, transverse tarsal, and metatarsopha-langeal joints should be performed. Muscle function is assessed and docu-mented. The position of the hindfoot relative to the forefoot should benoted, along with degree of rigidity. The Coleman block test should be per-formed to assess forefoot-driven hindfoot varus. The patient’s gait should beobserved to determine ground contact, the position of the heel, and the po-sition of the toes during stance [10]. Swing phase analysis should look forfoot drop and clawing of the toes.

Standing radiographs of the ankle and foot are mandatory. These radio-graphs allow evaluation of calcaneal pitch, lateral talo-first metatarsal angle,adaptive changes of the talus, and associated metatarsus abduction.

Nonsurgical treatment for residual adult clubfoot deformity is no differ-ent than that for other causes of cavovarus deformity. If mild residual defor-mity persists, with resultant pressure problems or callusing, a semirigidorthotic with metatarsal pad may be appropriate. More deformity may beimproved with either articulated or solid ankle-foot orthoses, in an attemptto control the hindfoot component. As with all symptomatic treatment, thegoal is to attempt to provide a plantigrade foot with even pressure distribu-tion. Unfortunately, this result is often difficult to achieve in the residualadult clubfoot. The limiting factor is often rigidity, with the more rigid de-formities responding less well to our bracing options.

309THE ADULT CLUBFOOT (CONGENITAL PES CAVUS)

Surgical treatment for the residual adult clubfoot depends on the specificdeformities that remain and need to be corrected. Although the primarygoal is to achieve a plantigrade foot and ankle, no one specific approachwill achieve this result. As with other reconstructive options, the preferredapproach is to attempt to preserve essential joints in an attempt to preserveflexibility, rather than to carry out fusions. If the foot is rigid, however, tri-ple arthrodesis may be the only reasonable alternative to correct the defor-mity. Most instances have a combination of fixed and supple deformity,which one hopes will be amenable to a combination of bone and soft tissueprocedures. The specific surgical procedures available for the correction ofthe adult clubfoot are the same procedures that have been described forother causes of cavovarus deformity. The use of each specific component de-pends on the components making up the deformity.

Almost all patients present with residual equinus deformity secondary toa tight heel cord. When the gastrocnemius component alone is tight, a gas-trocnemius recession (Strayer procedure) may be all that is necessary forcorrection; however, this case is usually the exception rather than the rule.More commonly, equinus deformity is more significant and will require ei-ther a percutaneous triple hemisection type release or, even more commonly,a formal Achilles tendon lengthening, with or without a posterior capsularrelease of the ankle. Overlengthening of the tendon should be avoided be-cause it can result in a calcaneus gait and weakness in plantar flexion [11].The presence of a flat-topped talus can be a cause of restricted ankle motionthat will not respond to soft tissue release and, in fact, may aggravate anklesymptoms when soft tissue contracture and a deformed talus coexist [12].

Soft tissue contractures may prevent the ankle joint from correcting fol-lowing Achilles tendon release. If this situation occurs, the deltoid ligamentcan be released at the posterior aspect of the medial malleolus. It may alsobe helpful to divide the posterior aspect of the syndesmosis between the tibiaand fibula, to allow the talus to rotate posteriorly in the ankle mortise. Usu-ally, a residual component of midfoot abduction will need to be addressedby Z-lengthening of the posterior tibial tendon [13]. Severe contracturemay require additional midfoot capsular releases. If the foot fails to correctafter medial talonavicular release, lateral column shortening can be used foradditional correction. It has the ability to correct hindfoot varus, forefootvarus, and forefoot abduction. Lateral column shortening can be performedthrough the cuboid, the lateral aspect of the calcaneus, or the calcaneocu-boid joint.

When the hindfoot does not correct passively to neutral, and in the ab-sence of arthritic changes in the subtalar joint, the residual varus deformityof the calcaneus is addressed with either a lateralizing calcaneal osteotomyor a Dwyer lateral closing wedge osteotomy. The Dwyer [14] closing wedgeosteotomy weakens the moment arm of the Achilles tendon and often can-not achieve full correction. The sliding calcaneal osteotomy is usually pref-erable [15]. Because the contracted plantar fascia plays a role in maintaining

310 WALLING

the height of the longitudinal arch and varus positioning of the calcaneus,release and stripping of the plantar fascia in conjunction with the calcanealslide often help reduce the height of the arch in patients who retain a degreeof flexibility.

Following correction of the hindfoot and midfoot deformities, the fore-foot is evaluated. Consideration of a dorsiflexion osteotomy of the firstmetatarsal is indicated for a plantar-flexed first ray. Failure to addressthis situation may lead to painful first metatarsal head overload syndromeand contribute to residual forefoot-driven hindfoot varus. The planar fascialrelease also assists in the correction of the first metatarsal. Overcorrectionshould be avoided because it may lead to hallux rigidus or transfer metatar-salgia. Occasionally, additional osteotomies of the second or third metatar-sals may be necessary [16].

The more typical tendon transfers (peroneus longus to brevis, modifica-tions of the Jones’ procedure, and other claw toes corrections) used for othercauses of cavovarus deformities are not commonly needed when treating theresidual adult clubfoot. However, an understanding of their principles anduses is important so that any situation encountered may be addressed. Be-cause these tendon transfers have been well described in other articles,they will not be represented here. A more likely need is the release of thetoe flexors secondary to the correction of the ankle equinus. A Z-lengthen-ing of the flexor hallicus longus may be performed at the same time andthrough the same incision as the tendoachilles lengthening. The flexor digi-torum longus to the lesser toes is usually released through individual inci-sions on the plantar aspect of the individual toes.

For more severe, rigid deformities, or when secondary degenerativechanges have developed, various fusions are indicated. Subtalar fusionis indicated for subtalar arthritis and can correct hindfoot varus by ro-tating the foot externally on the talus to close down the sinus tarsi be-fore stabilization. Calcaneocuboid fusion can be used for degenerativechanges at the calcaneocuboid joint or to shorten the lateral column.Triple arthrodesis is reserved for the patient who has rigid deformitywith arthritis at any of the joints forming the triple-joint complex. Un-fortunately, an associated ankle arthritis may make an extended anklehindfoot fusion necessary. The functional results of multiple fusionsare obviously less desirable, making them essentially last resort–typeprocedures. Fusions may be performed at one surgery as long as carefulattention is paid to the blood supply to the talus. The ankle should befused first, correcting as much deformity as possible. The subtalar, talo-navicular, and calcaneocuboid joints are then reduced and fused asneeded to correct any remaining deformity. A calcaneal osteotomy issometimes required to correct the hindfoot varus fully. A staged ap-proach is also reasonable, especially if a question exists regarding theseverity of the ankle’s degenerative changes. In this instance, it maybe better to perform the indicated hindfoot fusions and then, if the

Fig. 1. Standing preoperative ankle mortise shows no evidence of talar tilt but significant hind-

foot varus.

311THE ADULT CLUBFOOT (CONGENITAL PES CAVUS)

ankle becomes or remains symptomatic, proceed with treatment for theankle arthritis or malalignment.

In summary, the specific soft tissue and bony procedures indicated forcorrection of the residual adult clubfoot depend completely on the constel-lation of residual deformity that may exist. If the patient was successfullytreated at a younger age and has only limited deformity, all that may be re-quired is symptomatic treatment or bracing. It is to be hoped that flexibledeformities can be treated with a combination of soft tissue procedures

Fig. 2. Standing lateral radiograph of the ankle and foot demonstrates the varus and cavus

deformities of the hindfoot.

Fig. 3. Anteroposterior radiograph of the foot showing less midfoot abduction than seen

clinically because of the equinus ankle contracture.

312 WALLING

and osteotomies or limited fusions, which will not compromise the essentialjoints of the ankle, subtalar, and talonavicular joints. Unfortunately, morerigid deformities with adaptive degenerative changes require fusions withtheir associated functional loss in an attempt to obtain a plantigrade foot.

Case example

An 18-year-old woman with a history of left clubfoot treated with serialcasting in the first 2 years of life without subsequent treatment presents with

Fig. 4. Postoperative ankle mortise demonstrates correction of the hindfoot varus.

Fig. 5. Postoperative lateral radiograph shows the calcaneal osteotomy and the first ray

correction.

313THE ADULT CLUBFOOT (CONGENITAL PES CAVUS)

complaints of pain and difficulty walking, with increasing difficulty wearingconventional shoe wear. On physical examination she is 5 feet 7 inches talland weighs 190 lbs. Ankle motion demonstrates equinus position with mi-nus 10� of neutral and an additional 15� of plantar flexion. The ankle is sta-ble. The hindfoot is in varus and the midfoot is abducted. The forefootshows a plantar-flexed first ray and no evidence of clawing. Coleman blocktest is difficult to assess, secondary to the equinus ankle contracture. Hermotor strength, sensory examination, and vascular status are normal.

Fig. 6. Postoperative anteroposterior radiograph of the foot is more indicative of the residual

metatarsus adductus, which was clinically evident preoperatively.

314 WALLING

Preoperative radiographs include standing ankle mortise, ankle lateral, andanterior posterior foot (Figs. 1–3). She undergoes surgical correction, in-cluding open tendoachilles and flexor digitorum longus lengthening, frac-tional posterior tibial lengthening and midfoot capsular releases, andcalcaneal and first metatarsal dorsiflexion osteotomies. Surgery results ina plantigrade foot with 7� of ankle dorsiflexion and correction of her hind-foot varus. She has some residual midfoot abduction and her first ray is ina neutral position. Postoperative radiographs taken at 3 months demon-strate her corrections (Figs. 4–6).

References

[1] Beaty JH. Congenital foot deformities. In: Coughlin MJ, Mann RA, Saltzman CL, et al,

editors. Surgery of the foot and ankle. 8th edition. Philadelphia: Elsevier Inc.; 2007.

p. 1729–59.

[2] IraniRN, ShermanMS.The pathologic anatomyof clubfoot. J Bone Joint SurgAm1963;45:

45–52.

[3] MartinRF,Milo-MasonG,McComasA, et al.Neurogenic origin of talipes equinovarus. In:

Simon GW, editor. The clubfoot: the present and a view of the future. New York: Springer-

Verlag; 1993.

[4] RobertsonWWJr, CorbettD. Congenital clubfoot:month of conception.ClinOrthopRelat

Res 1997;338:14–8.

[5] Issac H, Handelsman JE, Badenhorst M, et al. The muscle in clubfoot: a histologic, histo-

chemical, and electron microscopic study. J Bone Joint Surg Br 1977;46:465–72.

[6] Felbrin Z, Gilal AN, Ezra E, et al. Muscle imbalance in the aetiology of idiopathic club foot:

an electromyographic study. J Bone Joint Surg Br 1995;77:586–601.

[7] Morcuende JA, Dolan IA, Dietz FR, et al. Radical reduction in the rate of extensive correc-

tive surgery for clubfoot using the Ponseti method. Pediatrics 2004;113(2):376–80.

[8] Tarraf YN, Carroll NC. Analysis of the components of residual deformity in clubfeet pre-

senting for reoperation. J Pediatr Orthop 1992;12:207–16.

[9] Huber H, Dutoit M. Dynamic foot-pressure measurement in the assessment of operatively

treated clubfeet. J Bone Joint Surg Am 2004;86(6):1203–10.

[10] Guyton GP,Mann RA. Pes cavus. In: CoughlinMJ,Mann RA, Saltzman CL, et al, editors.

Surgery of the foot and ankle. 8th edition. Philadelphia: Elsevier Inc.; 2007. p. 1125–48.

[11] Younger AS, Hansen ST. Adult cavovarus foot. J Am Acad Orthop Surg 2005;13:302–15.

[12] Haasbeek JF, Wright JG. A comparison of the long-term results of posterior and compre-

hensive release in the treatment of clubfoot. J Pediatr Orthop 1997;17:29–35.

[13] Botte MJ. Equinovarus deformity. In: Nunley JA, Pfeffer GB, Sanders RW, et al, editors.

Advanced reconstruction foot and ankle. Rosemont (IL): AAOS; 2004. p. 487–94.

[14] Dwyer FC. The present status of the problem of pes cavus. Clin Orthop Relat Res 1975;106:

254–75.

[15] Hansen ST Jr. Functional reconstruction of the foot and ankle. Philadelphia: Lippincott

Williams & Wilkins; 2000.

[16] Alexander IJ. Pes cavus. In: Nunley JA, Pfeffer GB, Sanders RW, et al, editors. Advanced

reconstruction foot and ankle. Rosemont (IL): AAOS; 2004. p. 495–502.