metatarsat osteotomy for the correction of metatarsus adductus

More documents

Recommendations

Info

$closure of deep fascia in ankle fracture surgery - The Podiatry Institute$

dicular to the weightbearing surface or the plantar surfaceof the foot.lf sagittal plane correction is also desired (dorsiflexionor plantarflexion) then the cortical hinge is appropriatelyangled to the transverse plane. A second convergingosteotomy is then performed and an appropriate wedgeof bone removed (Fig. 7). The exact size of the wedgeis determined by the extent of the deformity. The corticalhinge is weakened, the osteotomy is reduced andstabilized temporarily.The first metatarsal is identified through the medialincision, following deep fascial dissection, the firstmetatarsal cuneiform articulation is located. This willassist in identifying the epiphyseal growth plate. Theperiosteum is incised in an oblique fashion fromproximal-medial to distal-lateral along the course of theproposed osteotomy. The epiphyseal growth plate isidentified, and minimal stripping of the periosteum isperformed at this level. The osteotomy is then performedin an oblique fashion from distal-lateral to proximalmedial,preserving a medialcortical hinge in the sagittalplane. The osteotomy should be approximately 45degrees to the long axis of the first metatarsal (Fig. B).A second converging osteotomy is performed and anappropriate wedge section of bone removed, the hingeis weakened and the osteotomy is reduced and temporarilystabilized.Cenerally, osteotomies are performed on the centralthree metatarsals in a similar fashion. The decision to performtransverse or oblique base wedge osteotomies isa matter of surgeon's preference. An influencing factorin that decision is the type of fixation to be used. lf thesurgeon elects to use stainless steel wire in a verticalmattress fashion or a horizontal mattress fashion theoblique base wedge osteotomy will facilitate its use. Thetransverse base wedge is easily fixated with K-wires. Fixationtechniques will be discussed in more detail later.Both transverse and oblique base wedge osteotomiesare performed in the proximal metaphysis and requirean intact medial cortical hinge that lies primarily in thesagittal plane. Proper orientation of the osteotomy iscritical to maintaining the metatarsal head level in boththe sagittal and transverse planes. This also requiresaccurate wedge resections of bone from each affectedmetatarsal. The severity of the deformity will dictate theamount of bone that is removed. Usually a greateramount of bone removal is required from the medialmetatarsals (one and two) than from the lateral threemetatarsals. Maintenance of the medial cortical hingebecomes increasingly more difficult as the size of thewedge resection increases. lntraoperative radiographsare helpful to insure adequate wedge resection and correctivealignment of the metatarsals.Fig. 7. Oblique base wedge osteotomy of fifth metatarsal.Fig. 8. Oblique base wedge osteotomy of first metatarsal.Lepird ProcedureRichard Lepird (1981) introduced a new osseous procedurefor the correction of metatarsus adductus in thechild age six to eight years of age. Since its introductionit has been used extensively by the faculty of the PodiatryInstitute. The procedure uses rotational osteotomies ofthe central three metatarsals as opposed to wedge resections(Fig. 9).The procedure is performed through a standard dorsalthree incisional approach similar to that used for theModified Berman-Cartland procedure. The sequence ofexecution of the osteotomies will vary with the surgeon.The osteotomies of the first and fifth metatarsals are247
Fig. 9. Diagrammatic representation of the Lepird procedure for correctionof resistant metatarsus adductus (see text for details).oblique base wedge osteotomies as described previously.The central three osteotomies are rotational ortranspositional through and through cuts that do not requirebone resection. The osteotomy is initiated dorsallyat the junction of the proximal and middle one thirdsof the metatarsal. It is an oblique osteotomy orientedfrom dorsal-distal to plantar-proximal essentially parallelto the plantar aspect of the foot (approximately 45degrees to the dorsal surface of the metatarsal). Greatcare should be taken to insure that the osteotomy exitsproximal to the metatarsal cuneiform joint. When theosteotomy is performed a small portion of the cortex ispreserved to prevent motion between the proximal anddistal segments prior to fixation. The saw blade mustparallel the plantar aspect of the foot to produce anosteotomy that results in pure transverse plane motionwhen the distal segment is abducted on the proximalportion (Fig. 10). lf the saw blade is angled medially theresulting osteotomy would produce dorsiflexion as wellas abduction to the distal segment. Similarly, if the sawblade were angled laterally the resulting osteotomywould produce simultaneous plantarflexion and abduction.These type results may be warranted dependingupon the deformity.The Lepird procedure was developed to take advantageof the AO/ASIF concept of internal compression fixation.Fig. 10. Rotational osteotomy of lesser metatarsals. Saw blade is essentiallyparallel to plantar aspect of foot.Prior to complete transection of the metatarsal, fixationis performed using small cortical bone screws orientedperpendicular to the plane of the osteotomy. Temporaryfixation in the form of bone reduction forceps or K-wiresis not necessary because a small portion of the cortexhad been maintained. When the osteotomy is completed,the screw is placed across the osteotomy. Before thescrew is finally secured, the distal shaft portion of themetatarsal is rotated laterally into the desired position(Fig. 11). Radiographs are employed to evaluate theamount of correction. lf more or less correction isdesired, the screw can be loosened, the appropriate positionobtained and the screw secured (Fig. 12).COMPTICATIONS AND IIXATIONCritical to the use of transverse or oblique base wedgeosteotomies is the preservation of a medial cortical248
Page 1 and 2: METATARSAT OSTEOTOMY FOR THE CORREC
Page 3 and 4: Fig. 2. Preoperative radiographs, A
Page 5: Fig.5. Preoperative and postoperati
Page 9: pression fixation resulting in prim

metatarsat osteotomy for the correction of metatarsus adductus

Create successful ePaper yourself

Delete template?

Save as template?