(KArrsH osTEoToMY) - The Podiatry Institute

MODIFICATIONS OF THE AUSTIN HAttUX VATGUS REPAIR(KArrsH osTEoToMY)Stanley R. Kalish, D.P.M.INTRODUCTIONIn 1983, the Kalish Osteotomy was first presented. ltsintroduction was met with a normal amount of skepticismas osteotomies of the first metatarsal were not consideredrevolutionary.Kelikian reviewed more than 100 procedures for thecorrection of hallux abducto valgus. The podiatricliterature has added its share of osteotomies, derotationaltransposition osteotomy (DRATO), SCARF, Vogler, andothers. Some of these are still used today while othershave been discarded because of their manycomplications.ln 1962, Dr. Dale Austin presented a paper which waslater published in 1981 describing a distal metaphysealfirst metatarsal osteotomy (Fig. 1). The osteotomy was ahorizontally directed 60 degree V displacementosteotomy. The advantage of the osteotomy as cited byAustin and Leventen in Clinical Orthopedics and RelatedResearch in 1981 indicated intrinsic stability of theosteotomy without fixation and early ambulation withoutcasting. They reported a low rate of recurrence of thedeformity. The procedure was well accepted by podiatricsurgeons and is a commonly performed operation today.The disadvantages of the Austin Procedure:1) osteotomy d isplacement2) malposition3) delayed union, hypertrophic bone formation, andnonu nion4) Kirschner wire displacement and pin tractinfections if fixated5) limitation of first metatarsophalangeal joint rangeof motion.The Kalish modification addresses the complicationsof the original Austin procedure (Fig. 2). By creating a55 degree osteotomy which is intrinsically more stableand by adding rigid internal fixation in the form of twoparallel 2.7 mm cortical bone screws, the Austinosteotomy has been greatly improved. Patients have astable 55 degree well f ixated osteotomy which has beenscientifically created with the axis guide principle. Theyhave no Kirschner wire infections as all hardware is nowinternal (Fig.3). Earlier range of motion exercise and immediateambulation are permitted, thus avoiding jointlimitus. Patients are able to bathe in 10 days and are encouragedto return to closed shoes in 2 to 4 weeks.INDICATIONSThe indications for the Kalish osteotomy are similar tothose originally described by Austin. In our experienceand in studies currently underway by Drs. Downey andMalay at the Pennsylvania College of Podiatric Medicine,the Kalish osteotomy may be used to correct largerdegrees of metatarsus primus adductus than wasoriginally recommended. This increase in parameters ispermitted by the increased stability and rigid internal fixationof the osteotomy allowing greater lateral displacementof the capital fragment. However, care must betaken to avoid the troughing effect common to thoseosteotomies of greater than 18 degrees (Fig. a). Complicationsfrom this effect include fracture of the metatarsal,rotary instability (as the lateral cortex rotates in the plantarmedullary canal), and inability to correct high proximalarticular set angles with a single cut.Pelligrino in the Journal of the American PodiatricMedical Association,1986, correctly observed that somedegree of PASA will be corrected by unidirectional Austintype osteotomies. In attempting to stretch the indicationsfor this procedure we occasionally transfer the adductortendon which, according to Beck in Journal of theAmerican Podiatry Association , 1972, and Ruch 1982 (personalcommunications) will reduce intermetatarsalangles.ln our initial study of 64 patients we found an exceptionallyhigh frequency of hallux varus (5 out of 64 cases)and hallux adductus. This we attributed to the universaltransfer of the adductor tendon in our earlier studies.However, our dissection technique continues to transectthe fibular sesamoidal ligament and mobilize the fibularsesamoid. The adductor tendon is mobilized andsacrificed in those situations where we do not desire additionalintermetatarsal correction.14

Fig. 1. Sixty degree horizontal "V" osteotomy described by AustinFig. 2. Fifty-five degree Kalish modification of Austin procedure.Fig.3. Pin tract infection seen with external Kirschner wire fixationFig. 4. Troughing effect seen with excessive lateral displacement ofmetaphyseal osteotom ies.The following indications have been identified.1. Hallux abductus angle greater than 15 degrees.2. Metatarsus primus adductus 15 degrees or less.A. Without adductor transfer.B. Metatarsus primus adductus 15-18 degrees withadductor tendon transfer.3. Pain-free range of motion with no significantosteophytes.4. Absence of severe degenerative joint disease.TECHNIQUEUsing the concepts of anatomic dissection of the firstmetatarsophalangeal joint, an approximately 7 cm curvilinearincision is angled over the first metatarsophalangealjoint. This incision is slightly longer on theproximal segment to accommodate the longer dorsal cut(Fig. 5). The incision is deepened through the skin andsubcutaneous tissue to the level of the first metatarsophalangealjoint capsule. Dissection is carried downto the f loor of the f irst interspace. The adductor hallucistendon is released and tagged for possible use (Fig' 6).The fibular sesamoidal ligament is transected. The greattoe is adducted, and the sesamoidal plate should moveback beneath the metatarsal head.Dissection through the medial side of the joint is carriedalong the deep fascia and capsule to the plantaraspect of the joint. An inverted I capsular incision is thenperformed. An intact plantar medial blood supply ismaintained by this capsulotomy. After minimal resectionof the medial eminence of the first metatarsal, a smooth.045 Kirschner wire is placed through the medial to lateralcortex of the first metatarsal head to serve as an apicalaxis guide (Fig. 7). By appropriate placement of the axisguide the surgeon is able to plantarflex, dorsiflex, ormaintain the current level of the first metatarsal head.Additionally, either elongating, shortening, or no positionalalteration of the first metatarsal length may be obtainedby apical axis guide position (Fig. B).15

Fig. 5. Skin incision for Kalish osteotomyFig. 7. Axis guide positioning for neutral, plantarflexion and dorsif lexiondisplacement of metatarsal head.Fig. 6 A., 68. Adductor tendon transfer, and schematic diagram showingaxial sesamoid position after fibular sesamoidal ligament istransected.Fig. 8. Axis guideosteotomy.,&positioni ng for neutral, lengthening, or shortening16

Fig. 9. Placement of temporary Kirschner wires prior to permanentscrew fixation.Fig. 10. Osteotomy with one2.7 mm screw and one .045 and one .062Kirschner wire still in place.THE OSTEOTOMYUsing the apical axis guide, a 55 degree Vosteotomyis created with the sagittal saw. The dorsal osteotomy iscreated first. The dorsal wing must be long enough toaccommodate two 2J mm screws or one 2.7 mm screwand one 2.0 mm screw (Figs. 9, 10). The plantar cut ismade after completion of the dorsal cut. We feel thestability of the more critical dorsal cut is insured by thissequence.The apical axis guide Kirschner wire is removed andthe head is distracted and moved laterally. Careful observationof the joint is made to achieve maximum correction.A negative intermetatarsal angle must be correctedif this is seen to occur when the head is repositionedlaterally on the metatarsal neck. Creater than 50%displacement of the metatarsal can cause the undesirabletroughing effect. Smallamounts of PASA deviation maybe corrected by medial compression of the osteotomy.Prefixation IFIXATIONAfter translocation of the capital f ragment, prefixationwires are placed through the osteotomy. A .045Kirschner wire is placed distally across the dorsal cut ina dorsolateral to plantar medial direction. lt crosses theplantar aspect of the metatarsal medially proximal to theplantar wing of the osteotomy.10):This .045 Kirschner wire serves two functions (Figs. 9,1. Stabilization of the osteotomy is accomplished.2. Direction for later screw placement.A proximal .062 Kirschner wire (1.9 mm) is then placedand will serve as the second screw position (Figs. 9, 10).This leaves the middle portion of the osteotomy availablefor the central screw. This is the most important of thefixation points especially when a second screw cannotbe placed.Stage IA.062 Kirschner wire (1.9 mm) is introduced in the centralposition and immediately withdrawn. The techniquedescribed for osteosynthesis as follows:1. 2.0 mm central drill hole2.2] mm overdrill3. Countersink4. Depth gauge (12-18 mm range)5. Tap 2.7 mm6. Sink appropriate screwAt this point we have the .045 wire, the 2.V mm screw/and the .062 Kirschner wire. The second .062 wire isremoved and the identical technique used for placementof the second screw.Countersinking is especially important in preventingdorsal wing fracture.Stage llThe use of a2.0 mm screw as the second screw as proposedby Dr. Thomas Cain has its merits in small boneor in those situations where the osteotomy was accidentallycut too short (Fig. 11).17

ClosureThe adductor hallucis tendon transfer may be performedif additional intermetatarsal correction is desiied. Capsularcorrection by capsulorrhaphy is rarely indicated.All layers are approximated with 3-0 and 4-0 absorbablesuture of Dexon or Vicryl. Skin closure is generally accomplishedwith 5-0 absorbable suture.RETROSPECTIVE STUDYTwo hundred and sixty four (264) osteotomies havebeen performed at the Podiatry lnstitute since 1983. Thefirst 64 patients were intensely studied by questionnaireinterview and objective examinations. Preliminary resultsrevealed the following:1.92% of those patients questioned indicated abetter result than expected.2.98% indicated no recurrence of the deformity.3.98% had no screw discomfort.4. Postoperative edema was less than 6 weeks.COMPTICATIONSFig. 11. Fixation with one 2.7mm and one 2.0mm screws.Hallux varus is the most common complicationobserved in the Kalish modification (Fig. 12). Five out of64 patients observed in the initial study and three outof 200 patients in the later studies were observed to sufferf rom hallux varus. All were associated with adductortendon transfer and/or medial capsulorrhaphy.It is imperative that hallux first metatarsal and tibialsesamoid position be evaluated intraoperatively to avoidthese complications. Patients with less than 15 degreeintermetatarsal angles preoperatively should notundergo adductor tendon transfer.Stress fractures occurred in two out of 264 cases andwere found in the second metatarsal. The exact causeis not certain but may be related to inappropriate dorsaldisplacement of the first metatarsal head. Fracture of thedorsal shelf occurred in seven out of 264 osteotomiesand were treated by forefoot fiberglass splinting in combinationwith the Darco shoe.tig. 12. Hallux varus following Kalish procedure.Table 1oBfEcTtvE FtNDtNGS(64 PATTENTS)PreopPostopAverage CorrectionMetatarsus primus adductus14 degrees3 degrees11 degreesHallux abductus angle30 degrees16 degrees14 degrees1B

Careful planning of the osteotomy length and propercountersinking of screw heads will avoid this complication.Norlunion and delayed union have not beenobserved in this study.CONCTUSIONSThe benefits of modifying the Austin hallux valgus correctionby the Kalish osteotomy can be summarized asfollows:1. Rigid internal fixation by two 2.7 mm bone screwsprovide primary bone healing.2. The osteotomy is intrinsically stable due to the55 degree V angulated osteotomy.3. No pin tract infections as all hardware is internal.4. The procedure has high patient acceptance.5. Full range of motion with early active andpassive dorsiflexion.6. Bathing in 10 to 14 days is permitted and the patientcan return to closed shoes in 2to 4 weeks.ReferencesAustin D, Leventen : A new osteotomy for hallux valgus.Cli n Orthop 157:25, 1981.Kelikian H: Hallux Valgus and Ally Deformities of theForefoot and Metatarsalgia. Philadelphia, WBSaunders Co, 1965.John A. Ruch, D.P.M. and Thomas Cain, D.P.M.: personalcommunications, 1988.Harry Vogler, D.P.M.: personal communications, 1987'19