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D Paley

Publications and source records attributed to D Paley.

At least 19 recordsLinked to original sources

A review for pediatricians on limb lengthening and the Ilizarov method.

As recently as 1986, limb lengthening in children was considered by most North American orthopedic surgeons to be both dangerous and impractical. Previous attempts were plagued by unacceptably high rates of serious complications such as nerve palsy, deep infection, malunion, broken hardware, and stiff joints. With the recent introduction of the Russian Ilizarov method and apparatus for limb lengthening, a tremendous groundswell of interest has risen. Despite a steep learning curve, many Western centers have now reproduced Ilizarov's clinical results. The important advances over prior methods are partly biologic and partly hardware related. Ilizarov's principles require a minimally invasive, low-energy osteotomy, stable external fixation, a latency period before commencing distraction, and gradual lengthening of 1 mm/d in divided doses (0.25 mm four times per day). The article reviews the background of this new technique and provides an update on results reported over the past year. There is disagreement regarding precise indications for limb salvage (lengthening) of congenital limb deficiencies versus amputation. The role of extended lengthening in dwarfism also remains controversial.

Bone Lengthening

Malalignment and degenerative arthropathy.

The axial relationship of the joints of the lower extremity reflects both alignment and orientation. Static considerations are useful for preoperative planning and deformity correction, but dynamic considerations including compensatory gait may be more relevant clinically. Laboratory animal models have been developed that simulate the deleterious effect of malalignment on articular cartilage. Malalignment disturbs the normal transmission of force across the knee, and altered stress distribution related to deformity has been demonstrated in cadaver models using pressure-sensitive film. No prospective data are available to document the natural history of malalignment, but several retrospective studies suggest the clinical course is one of gradual progression resulting in degenerative arthropathy. The long-term follow-up of fractures is less definitive, and difficult to interpret considering the bias inherent in patient selection. Although direct clinical evidence of a cause-and-effect relationship between malalignment and arthrosis has not been possible, substantial evidence from the orthopedic literature supports this hypothesis.

Animals

Biomechanics of malalignment.

This article summarizes the range and variation of femorotibial alignment, the horizontal orientation of the hip, knee, and ankle joint line, and other pertinent anatomic factors of the lower extremity in normal population groups evenly divided according to gender and age. Although the present data deals only with a two-dimensional frontal plane analysis, it should provide valuable information for subsequent clinical and basic science investigations.

Adult

Deformity planning for frontal and sagittal plane corrective osteotomies.

The authors have developed a universal system of geometric deformity planning based on the mechanical or anatomic axes. The place where the axes intersect is the center of rotation angulation (CORA) of a deformity. Osteotomy level and type should be considered relative to the CORA to avoid creating secondary deformities. This type of planning is applicable to both frontal and sagittal plane deformities.

Bone Malalignment

New concepts in high tibial osteotomy for medial compartment osteoarthritis.

Medial compartment osteoarthritis remains a clinical challenge for the orthopedic surgeon. Accurate preoperative planning is an integral part of management. MCOA with genu varum is not a single condition but a family of related deformities. One single technique may not be appropriate for all the permutations. An individualized approach is necessary to address the many facets of this complex disorder. Treatment must begin with recognition of all of these facets through careful history and physical examination and radiographic evaluation and through preoperative planning of the location of the deformity (femur, tibia, or knee joint), level of angulation, magnitude of the deformity, and plane of the angulation. One can then formulate a treatment plan to address the problems identified. Surgeons should not become rigid in their choice of method or device, but also consider its appropriateness to address the problems to be corrected. Because the patient seeks to prolong the life of the knee before joint replacement, a comprehensive approach achieving as accurate a correction as possible should be associated with the best possible outcome. In total knee replacement, the important emphasis has been on achieving correct bony alignment and soft-tissue balance. With osteotomy, the emphasis has been on bony alignment. However, soft-tissue balance should also be considered an important element in preserving the knee in osteotomy surgery.

Bone Malalignment

New procedures for tightening knee collateral ligaments in conjunction with knee realignment osteotomy.

Collateral ligament laxity has recently been recognized as an important component of frontal plane malalignment. The authors have developed new surgical techniques to re-tension lax collateral ligaments. Twenty-three collateral ligament re-tensioning with bony alignment were carried out in 17 patients, with 19 knees being graded excellent, 2 fair, and 2 poor. Recurrence of significant laxity was noted in one patient.

Adolescent

Accuracy of correction of complex lower-extremity deformities by the Ilizarov method.

Gradual mechanical distraction with the Ilizarov external fixator was used on 28 limbs in 23 patients to correct complex lower-extremity deformities of diverse causes. To determine the accuracy of realignment and deformity correction, the charts and radiographs were reviewed retrospectively. Preoperative long-standing anteroposterior radiographs of the entire lower extremity were compared with those obtained at the most recent follow-up visit. The parameters used to assess accuracy of correction were joint alignment and joint orientation. Alignment was determined by mechanical axis deviation (MAD) and mechanical tibiofemoral angle (mTFA). The preoperative MAD averaged 48 mm and the postoperative MAD 8.6 mm. The preoperative mTFA averaged 16 degrees and the postoperative mTFA 3 degrees. The result of deformity correction from early cases was compared with the result obtained from recent cases. Residual MAD averaged 13.2 mm in the early group and 6.4 mm in the recent group. Residual mTFA averaged 4.7 degrees in the early group and 2.2 degrees in the recent group. Gradual correction by dynamic external fixation can restore alignment and correct complex deformities with great accuracy. These results suggest the accuracy of correction increases with surgical experience.

Adolescent

Variables affecting time to bone healing during limb lengthening.

Radiographs and charts of 114 consecutive patients who underwent 140 lower-extremity bone-segment lengthening procedures using the Ilizarov external fixator were reviewed. Patient age, bone segment (femur, tibia), corticotomy level (metaphyseal, diaphyseal, double level), and distraction gap (DG) were recorded. Distraction-consolidation time (DCT) was defined as the interval in months from the date of the corticotomy until the DG was healed according to radiographic and manual testing criteria. Distraction-consolidation time had a direct linear relationship with the magnitude of the DG. Distraction--consolidation time versus DG was significantly less for femoral than tibial lengthening. Patients 20 years and older healed slower than patients younger than the age of 20 years. Patients 20 to 29 years old healed faster than patients older than 30 years and slower than patients younger than 20 years. Diaphyseal lengthening healed more slowly than metaphyseal lengthening. Double-level lengthening reduced the DCT when the DG was greater than 4 cm. Distraction--consolidation index--DCT divided by DG--was not a constant. Distraction--consolidation index decreased with increasing DG. To facilitate prediction of bone-healing time, graphs were developed demonstrating the average treatment time +/- 2 SD expected for a specific amount of lengthening, considering the bone segment, the level of osteotomy, and the age of the patient.

Adolescent

Knee range of motion in isolated femoral lengthening.

Twenty-five patients underwent isolated Ilizarov femoral lengthenings (mean lengthening, 6 cm). A retrospective review of the charts showed the specific changes in knee range of motion (ROM) during lengthening, after removal of the frame, and at the final follow-up examination. A decrease in ROM was seen during lengthening to an average minimum of 37 degrees +/- 15 degrees. Toward the end of the consolidation phase, improvement to 69 degrees +/- 28 degrees was noted. A progressive increase in ROM was seen after frame removal. Mean preoperative flexion was 127 degrees +/- 16 degrees, and at follow-up flexion was 122 degrees +/- 23 degrees (p = 0.191). Of the five patients who did not achieve 120 degrees flexion at the final follow-up examination, three had a diminished ROM (average, 107 degrees) at the outset. Two patients lost more than 15% of their preoperative flexion. There was no correlation noted between worst ROM (during lengthening) and final ROM at the last follow-up examination.

Adolescent

Mechanical distraction for treatment of severe knee flexion contractures.

Ten patients (14 knees) with severe knee flexion contractures were treated by gradual mechanical distraction using either the Ilizarov or Orthofix external fixator. Range of motion improved from an average flexion contracture of 60 degrees before surgery to 16 degrees at the follow-up evaluation. Range of motion results were graded good or excellent in five knees, fair in two knees, and poor in three knees. Average total arc of motion remained essentially unchanged when comparing the preoperative (59 degrees) with the follow-up results (63 degrees). However, the functional position of this arc improved significantly. Problems encountered included a "rebound" phenomena after frame removal, with loss of the temporarily increased total arc of motion. The role of hamstring tenotomy and radical posterior knee release remains unclear.

Adolescent

Correcting torsional deformities with Ilizarov's apparatus.

Patients undergoing limb lengthening with circular fixators often have rotational deformities requiring correction as well. At the end of lengthening, special rotation constructs are added to the Ilizarov frame to correct the rotational deformity. Unfortunately, the bone is usually eccentrically positioned in the rings, leading to secondary translational deformities after derotation. A trigonometric equation can predict the amount of inadvertent translation (t) that occurs with a given amount of derotation. Factors in this equation include the distance from the center of the ring to the outer edge of bone (r) and the amount of planned derotation (theta): t = (r sin theta)/sin (90 -theta/2). This sinusoidal function for derotation angles of less than 45 degrees can be approximated as a simple equation: t = 0.017 theta r. Armed with this information, the surgeon may calculate how much translation will be induced by the derotation maneuver. If the amount of predicted translation is deemed significant, then a more complex derotation frame with outriggers can be constructed to change the center of rotation to the middle of the eccentric bone. Alternatively, the translation induced by rotation can later be corrected with a translation construct.

Bone Lengthening

Intra-articular fractures of the calcaneus. A critical analysis of results and prognostic factors.

Forty-four patients who had had fifty-two calcaneal fractures were managed with open reduction and internal fixation. The results were reviewed retrospectively, between four and fourteen years after the operation, with use of an evaluation system for the hindfoot and with plain radiographs. The characteristics of the patients that were associated with an unsatisfactory outcome were an age of more than fifty years, a greater body weight, work involving strenuous labor, and increased time missed from work due to the injury. Other prognostic variables associated with an unsatisfactory result included subtalar incongruity, osteoarthrosis of the talonavicular joint and the ankle, an increased heel width, a decreased fibulocalcaneal space, and a decreased Böhler-angle ratio of the fractured to the normal side. The heel height, fat-pad height, arch angle, talocalcaneal angle, and length of the Achilles-tendon fulcrum were not related to the outcome. Patients who had had a tongue-type fracture had a better result than those who had had a central depression fracture, while those who had had a central depression fracture had a better outcome than those who had had a comminuted fracture. Comminution of tongue and large central-depression fractures was associated with a worse prognosis. The most common most painful area in the patients who had a satisfactory outcome was the lateral aspect of the hindfoot, while in those who had an unsatisfactory result, it was the heel pad.

Absenteeism

The correction of complex foot deformities using Ilizarov's distraction osteotomies.

Twenty-five very complex foot deformities were treated by Ilizarov distraction osteotomies. The osteotomy types included supramalleolar, U, V, posterior calcaneal, talocalcaneal neck, midfoot, and metatarsal osteotomies. In addition, the leg was lengthened and widened in most cases. The mean treatment time was 6.4 months. There were 20 minor or major complications related to the foot osteotomies in 18 feet, including deep pin-tract infection in three, failure of osteotomy separation in nine, acute postoperative tarsal tunnel syndrome in two, toe contractures in three, wire breakage or cutout in two, and buckle fracture in one. Nineteen secondary procedures were required in 13 patients to treat these complications. The final result was a plantigrade foot in 22 in late follow-up evaluation. The three nonplantigrade feet were attributable to unrecognized heel varus in one, ball and socket ankle joint in one, and partial growth arrest progressive deformity in one. Gait was improved in all cases. Pain was eliminated in all but two patients. Based on these criteria, the results were judged to be satisfactory in 22 and unsatisfactory in three. The Ilizarov method can successfully correct complex foot deformities despite complications.

Adult

Open reduction and circular external fixation of intraarticular calcaneal fractures.

Open reduction and internal fixation techniques do not allow early weight bearing. In an effort to develop a better method to obtain calcaneal fracture reduction and maintain it in the face of early weight bearing, a circular external fixator was applied to seven patients in combination with a limited lateral approach and open reduction and internal fixation of the depressed subtalar joint fragments. The operative technique uses the Ilizarov circular external fixator to obtain a ligamentotaxis reduction, following which the depressed subtalar joint fragments are elevated open; then, the fixator is used to reduce the lateral translation. All displacements of the fracture fragments are corrected. This method proved successful in six patients, all of whom achieved a satisfactory result with anatomic restoration of the subtalar joint and heel. One patient went on to late partial collapse of the posterior facet. Subtalar motion was greater than 50% in four of seven patients. None of the patients complained of heel pad pain, which was attributed to the desensitization of the heel by early weight bearing. This technique has produced encouraging preliminary results in two- to four-year follow-up evaluation.

Calcaneus

Mechanical axis deviation of the lower limbs. Preoperative planning of uniapical angular deformities of the tibia or femur.

Angular deformities of the tibia or femur in the frontal plane lead to mechanical axis deviation of the lower limb and malorientation of the joints above and below the level of deformity. Accurate correction of the malalignment and of the joint orientation is important for function and to prevent joint degeneration. An accurate yet simple method to determine the apex of deformity and the type of correction required is based on the joint reference lines of the hip, knee, and ankle, and the individual mechanical axis lines of each bone segment. If the osteotomy is performed at the level of the apex of the deformity, then the only correction needed is angulation. If the osteotomy is performed at a level proximal or distal to the apex, then translation in addition to angulation is necessary to accurately correct the deformity.

Femur

Mechanical axis deviation of the lower limbs. Preoperative planning of multiapical frontal plane angular and bowing deformities of the femur and tibia.

Multiapical deformities complicate the process of preoperative planning. It is necessary to determine the level of each apex of deformity to plan accurate correction. The basic principles of mechanical axis realignment and joint orientation need to be preserved. Using the joint reference lines and mechanical axis of each bone segment, one can accurately determine the apex of each deformity. Bowing deformities are multiapical angular deformities. There are two types of bowing deformities: compensated and noncompensated. Typical examples of compensated bowing are the anterolateral and posteromedial bows of the tibia. A noncompensated bow is typical of the deformity seen in rickets.

Femur

Treatment of congenital pseudoarthrosis of the tibia using the Ilizarov technique.

The principle of treatment of congenital pseudoarthrosis of the tibia (CPT) with the Ilizarov method corrects all angular deformity and maximizes the cross-sectional area of union of the pseudoarthrosis. Fifteen patients with a total of 16 CPT were treated using the Ilizarov apparatus. Various forces were used to treat the pseudoarthrosis site including compression, distraction, open reduction, resection and shortening, resection and bone transport, and invagination of one end in the other. Lengthening was performed in 12 of the 16. Deformity was corrected in all cases. The union rate was 94% with one treatment and 100% with two treatments. There were five refractures, three early and two late. Previous pin sites, residual angular deformity, and natural history were considered predisposing factors for refractures. One patient refractured twice but remained ununited. Fifteen remained united, with a mean follow-up period of four years (range, two to seven). There were two residual deformities, one in the regenerate and one at the level of the CPT.

Adolescent

Ilizarov technique in treatment of congenital hand anomalies. Two case reports.

An Ilizarov apparatus was successfully used in the treatment of a six-year-old child with a radially deviated hand caused by congenital pseudoarthrosis of the distal radius after previous traditional surgery failed. The limb length was restored, the pseudoarthrosis healed, and the deviated hand corrected. A second child, five years old, with Poland's syndrome, had a 90 degrees flexion contracture of the wrist that was treated with the Ilizarov apparatus. The flexion contracture was gradually corrected. It seems that the Ilizarov apparatus can be an important tool in the treatment of complex limb deformities.

Child