STRYDE versus PRECICE magnetic internal lengthening nail for femur lengthening.

INTRODUCTION: Magnetic internal lengthening nails (MILNs) have been used for femoral lengthening to avoid complications associated with external fixation. The titanium version of the MILN (PRECICE®) has been in use since 2011 but had limitations (50-75 lb) in post-operative weight bearing. A new stainless-steel version of the MILN (STRYDE®) allows 150-250 lb of post-operative weight bearing. The aim is to compare the outcomes of using these two different MILNs for both unilateral and bilateral femoral lengthening. METHODS: A single-center, retrospective cohort study was conducted in which patients' records were reviewed from the period from January 2017 to March 2020. A total of 66 femoral lengthening procedures were included in the study and were divided into two groups: STRYDE® group (30 femora) and PRECICE® group (36 femora). Outcomes assessed were the 6-months post-operative Limb Deformity-Scoliosis Research Society (LD-SRS) Score, adjacent joint range of motion (ROM), average distraction rate, bone healing index (BHI), and complications. RESULTS: No statistically significant difference was found between the two groups in regard to the (LD-SRS) score, hip ROM, or knee ROM. Statistically significant differences were found between the two groups in regard to BHI (average of 0.84 months/cm and 0.67 months/cm for STRYDE® and PRECICE®, respectively) and distraction rate (average of 0.6 mm/day and 0.9 mm/day for STRYDE® and PRECICE®, respectively). No mechanical nail complications were reported in the STRYDE® group compared to three events of nail failure in the PRECICE® group. One femur in the PRECICE® group needed BMAC injection for delayed healing compared to four femurs in the STRYDE® group. CONCLUSION: The STRYDE® MILN yields comparable functional results to those of PRECICE® MILN and shows fewer mechanical nail complications. However, STRYDE® MILN requires a slower distraction rate and yields slower healing (larger BHI). LEVEL OF EVIDENCE: Level III, Therapeutic study.

Gene expression of osteogenic factors following gene therapy in mandibular lengthening.

This study investigated the effect of gene therapy on the expression of osteogenic mediators in mandibular distraction osteogenesis rabbits. Bilateral mandibular osteotomies were performed in 45 New-Zealand rabbits. After a latency of 3 days, the mandibles were elongated using distractors with a rate of 0.8 mm/d for 7 days. After the completion of distraction, the rabbits were randomly divided into 5 groups: 2 µg (0.1 µg/µL) of recombinant plasmid pIRES-hVEGF165-hBMP-2, recombinant plasmid pIRES-hBMP2, recombinant plasmid pIRES-hVEGF165, pIRES, and the same volume of normal saline were injected into the distraction gap of groups A, B, C, D, and E, respectively, followed by electroporation. Three animals were killed at the 7th, 14th, and 28th day after gene transfected in different groups, respectively. The lengthened mandibles were harvested and processed for immunohistochemical examinations; the mean optic densities (MODs) and integral optical density of bone morphogenetic protein (BMP-2) and transforming growth factor ß1 (TGF-ß1)-positive cells were measured by CMIAS-2001A computerized image analyzer. The data were analyzed with SPSS (SPSS Inc, Chicago, IL). Bone morphogenetic protein 2 and TGF-ß1 staining was mainly located in inflammatory cells, monocytes, fibroblasts, osteoblasts, osteocytes, and chondrocytes in the distraction zones. Their strongest expression reached to the peak at the seventh day and decreased at the 14th day of consolidation stage; at the 28th day, they expressed weakly. Image analysis results show that, at the seventh day, the expression of BMP-2 in group B (0.26 ± 0.03, 0.36 ± 0.02) was the strongest; there was significant difference among them (P < 0.01), whereas the expression of TGF-ß1 in group C (0.38 ± 0.06, 1.05 ± 0.19) is strongest followed by group A (0.34 ± 0.05, 0.95 ± 0.16) and B (0.33 ± 0.07, 0.90 ± 0.19). At every time point, the level of expression of BMP-2 and TGF-ß1 in gene therapy groups (groups A, B, and C) was remarkably higher than those in non-gene therapy groups(groups D and E). There were significant differences between gene therapy groups and non-gene therapy groups (P < 0.05 or P < 0.001). These results indicated that local gene transfection can up-regulate the expression of osteogenic mediators (BMP-2 and TGF-ß1), which may promote cell differentiation and proliferation and stimulate extracellular matrix synthesis and new bone formation in distraction gap.

Subtrochanteric shortening osteotomy combined with cemented total hip arthroplasty for Crowe group IV hips.

BACKGROUND: Total hip arthroplasty (THA) is a challenging surgical procedure that can be used to treat severely dislocated hips. There are few reports regarding cemented THAs involving subtrochanteric shortening osteotomy (SSO), even though cemented THAs provide great advantages because the femur is generally hypoplastic with a narrow, deformed canal. PURPOSES: We evaluated the utility of cemented THA with SSO for Crowe group IV hips, and assessed the relationship between leg lengthening and nerve injury. Our goal was to describe surgical techniques for optimizing surgical outcomes while minimizing the risk of nerve injury. METHODS: We retrospectively reviewed 34 cases of cemented THAs with transverse SSO for Crowe group IV. Prior to surgery, mean hip flexion was 93.1° (40°-130°). The mean follow-up period was 5.2 years (3-10 years). RESULTS: Bone union took an average of 7.7 months (3-24 months). Mean leg lengthening was 40.5 mm (15-70 mm) and was greater in patients without hip flexion contracture. None of the patients experienced any nerve injuries associated with leg lengthening, and radiographic evidence of loosening was not observed at the final follow-up. CONCLUSIONS: SSO combined with cemented THA is an effective treatment for severely dislocated hips. Leg lengthening is not necessarily associated with nerve injuries, and the likelihood of this surgical complication may be related to the presence of hip flexion contracture.

[The sphenomandibular ligament: an anatomical obstacle to ramus lengthening]. / Le ligament sphénomandibulaire, obstacle anatomique à l'allongement du ramus.

INTRODUCTION: The sphenomandibular ligament is strong and its insertion below the medial cut of the sagittal split osteotomy explains that it is a barrier to the mobilization of the distal segment. It is the main obstacle to ramus lengthening. We describe the disinsertion technique with an anatomical dissection. SURGICAL TECHNIQUE: After sagittal split ramus osteotomy, we verify that a stable occlusion has been achieved without straining. In case of resistance, a 90° angled periosteal rugine is introduced below the periosteum, against the medial cortex. It is used to detach the last fibers of the medial pterygoid muscle under visual control, and it is carefully moved to the lingula to detach the anterior sphenomandibular ligament insertion. DISCUSSION: In case of a very short ramus, there is hypoplasia of soft tissues, especially the pterygomasseteric sling, and the stylomandibular ligaments are short. This is why it seems necessary to release the sphenomandibular ligament in all forms of ramus lengthening.

Removal of a Broken Stainless-Steel Intramedullary Lengthening Stryde Nail: A Case Report and Review of the Literature.

CASE: We report a 15-year-old female patient who underwent femur lengthening with a stainless steel intramedullary lengthening Stryde nail that broke at the end of the lengthening course and required removal. Given the solid noncannulated nature of the nail, this required special strategy to remove broken parts. CONCLUSION: Stryde nails are stainless steel lengthening nails that were developed to allow more freedom with weight bearing. Regardless of this change, hardware failure remains possible. In addition to maintaining regenerate integrity, a surgeon must be creative when attempting to remove solid nail types because many techniques for removing failed hardware were developed for cannulated devices.

Flexible intramedullary nails for limb lengthening: a comprehensive comparative study of three nails types.

This study aims to investigate the comparative study of calcium phosphate coatings for flexible intramedullary nails (FINs) used to lengthen long tubular bones. The presence of a calcium phosphate coating deposited by micro-arc oxidation (MAO) or a composite coating based on a co-polymer of vinylidene fluoride with tetrafluoroethylene (VDF-TeFE) and hydroxyapatite (HA) on the surface of the FIN significantly enhanced the regeneration of bone in the area of osteotomy during limb lengthening by combined osteosynthesis. The investigation of the physico-chemical properties of the FIN coated with calcium phosphate via MAO demonstrated that the improved bone tissue formation resulted from favourable conditions for adhesion, proliferation and differentiation of multipotent stem cells into osteoblasts on the coating surface. The composite coatings only stimulated the formation of bone tissue in vivo, primarily because of the piezoelectric properties of the VDF-TeFE co-polymer.

Can polyaryletherketone cage be used to achieve union and maintain correction in anterior calcaneal lengthening osteotomy for treatment of flexible flatfoot?

A structural graft is often used to maintain correction and achieve union after anterior calcaneal lengthening osteotomy for treatment of flexible flatfoot. Autograft, the current gold standard, is limited in availability and configuration and is associated with donor site morbidity in as much as 48%, whereas the alternative allograft carries risks of disease transmission and collapse. Polyaryletherketone cage, with a healing rate similar to that of autograft, high stability, and no donor-site morbidity, has been used in spine surgery. However, its use has not been documented in foot and ankle surgery. We reviewed 15 patients with painful flatfeet after failure of conservative treatment who were treated by anterior calcaneal lengthening osteotomy using polyaryletherketone cage instead of bone graft. Minimum follow-up was 1 year (average, 1.27 years; range, 1-1.5 years). The male-female ratio was 1:1.5 (six males, nine females). Mean age at time of surgery was 10.8 ± 1.7 years (range, 8-13.5 years). Minimum follow-up was 1 year (average, 1.27 years; range, 1-1.5 years). Nine patients had a unilateral procedure and three had a simultaneous bilateral procedure, for a total of 15 operated feet (seven right and eight left). The paired t-test result was statistically significant in comparison of radiographic measurements at presurgery and postsurgery with P value <0.001. All cases showed full union clinically and radiographically at last follow-ups and no complications occurred. Our data suggest that polyaryletherketone cage may be used as a structural graft option for anterior calcaneal lengthening osteotomy.

Inflammatory-Driven Angiogenesis in Bone Augmentation with Bovine Hydroxyapatite, B-Tricalcium Phosphate, and Bioglasses: A Comparative Study.

INTRODUCTION: The clinical use of bioactive materials for bone augmentation has remained a challenge because of predictability and effectiveness concerns, as well as increased costs. The purpose of this study was to analyse the ability to integrate bone substitutes by evaluating the immunohistochemical expression of the platelet endothelial cell adhesion molecules, vascular endothelial growth factor, collagen IV, laminin, and osteonectin, in the vicinity of bone grafts, enabling tissue revascularization and appearance of bone lamellae. There is a lack of in vivo studies of inflammatory-driven angiogenesis in bone engineering using various grafts. METHODS: The study was performed in animal experimental model on the standardized monocortical defects in the tibia of 20 New Zealand rabbits. The defects were augmented with three types of bone substituents. The used bone substituents were beta-tricalcium phosphate, bovine hydroxyapatite, and bioactive glasses. After a period of 6 months, bone fragments were harvested for histopathologic examination. Endothelial cell analysis was done by analysing vascularization with PECAM/CD31 and VEGF and fibrosis with collagen IV, laminin, and osteonectin stains. Statistical analysis was realized by descriptive analysis which was completed with the kurtosis and skewness as well as the Kruskal-Wallis and Mann-Whitney statistical tests. RESULTS: The discoveries show that the amount of bone that is formed around beta-tricalcium phosphate and bovine hydroxyapatite is clearly superior to the bioactive glasses. Both the lumen diameter and the number of vessels were slightly increased in favor of beta-tricalcium phosphate. CONCLUSION: We can conclude that bone substitutes as bovine bone and beta-tricalcium phosphate have significant increased angiogenesis (and subsequent improved osteogenesis) compared to the bioactive glass. In our study, significant angiogenesis is linked with a greater tissue formation, indicating that in bone engineering with the allografts we used, inflammation has more benefic effects, the catabolic action being exceeded by the tissue formation.

Biomechanical advantage of lengthening of the femur with an external fixator over an intramedullary nail.

The present experimental study investigated biomechanical differences in methods of femoral lengthening using a monolateral external fixator only and using an external fixator over an intramedullary nail. Three materials, namely polyvinyl chloride rods, composite synthetic bone, and cadaver-bone, were tested using the MTS machine. We evaluated the differences of axial stiffness according to the presence of a nail or the numbers of half-pins (two or three half-pins) that were fixed at each side of osteotomy. The addition of a nail may increase the axial stiffness of the frame of monolateral external fixator for limb lengthening. Additionally, it is enough to distract the femur with fixing two half-pins at each side, when using the technique of lengthening over a nail.

[Atraumatic bone expansion: Interest of piezo-surgery, conicals expanders and immediate implantation combination]. / L'expansion osseuse atraumatique : intérêts de la combinaison pièzo-chirurgie, expanseurs coniques et implantation immédiate.

The durability of dental implants depends on the presence of a 1mm coating bone sheath all around the fixture. Therefore, bone resorption represents a challenge for the practitioner. Bone expansion is a surgical technique that allows the management of horizontal bone atrophy. Cortical bone splitting allows for an enlargement of the residual crest by displacement of the vestibular bone flap. The immediate placement of implants secures the widening and allows for a 97% survival rate. However, bone expansion is hard to undertake in sites with high bone density. Furthermore, the use of traditional instruments increases patient's stress and the risk for an interruptive fracture during bone displacement. Non-traumatic bone expansion is one solution to this problem. The combination of piezo-surgery and conical expanders allows for a secured displacement of the selected bone flap as well as an immediate implant placement, avoiding the risk of slipping, overheating, or fracture, all within an undeniable operative comfort. Non-traumatic bone expansion is a reliable, reproducible, conservative, and economical in time and cost procedure. We describe our atraumatic bone expension and immediate implant placement technique in high bone density sites and illustrate it by a clinical case.

Is structural hydroxyapatite tricalcium-phosphate graft or tricortical iliac crest autograft better for calcaneal lengthening osteotomy in childhood? interim results from a randomised, controlled non-inferiority study.

AIMS: To compare the structural durability of hydroxyapatite-tricalcium phosphate (HATCP) to autologous iliac crest bone graft in calcaneal lengthening osteotomy (CLO) for pes planovalgus in childhood. PATIENTS AND METHODS: We present the interim results of ten patients (HATCP, n = 6 and autograft, n = 5) with a mean age of 11.5 years (8.2 to 14.2) from a randomised controlled non-inferiority trial with six months follow-up. The primary outcome was the stability of the osteotomy as measured by radiostereometric analysis. A non-inferiority margin of ≤ 2 mm osteotomy compression was set. RESULTS: At six months the data showed that the osteotomy had been compressed by a mean 1.97 mm (99.8% confidence interval -1.65 to 5.60) more in the HATCP group than in the autograft group. Migration of the CLO grafted with HATCP stabilised at six months rather than at six weeks with autograft. CONCLUSION: This is the first randomised trial to compare the efficacy of HATCP graft with autograft in terms of stability of CLO in children. Because of problems with the HATCP the trial was stopped. We do not recommend HATCP graft in its current structure for use in unfixed CLOs. Cite this article: Bone Joint J 2016;98-B:1554-62.

Distraction osteogenesis for reconstruction of mandibular symphyseal defects.

OBJECTIVE: We investigated the feasibility of arched trifocal distraction osteogenesis for reconstruction of mandibular symphyseal defects. DESIGN: Four adult canine subjects were used. An external apparatus was designed to allow trifocal distraction around an arc. An anterior mandibulectomy was performed between the third premolars bilaterally. The bony defect was regenerated using trifocal distraction osteogenesis at a rate of 1 mm a day bilaterally. New arced bone was produced over a period of 20 to 35 days. The apparatus functioned as an external fixator for the ensuing 6 weeks. The apparatus was then removed, the dogs were returned to their preoperative diet, and were killed after 2 weeks of observation. MAIN OUTCOME MEASURES: Grossly a smooth arc of bone was formed measuring 4.5 to 5.5 cm in length, 2.2 to 3.0 cm in height, and 1.3 to 1.5 cm in width. Histologically all specimens demonstrated direct membranous bone growth. Radiographically opaque columns were seen streaming in the direction of distraction. CONCLUSIONS: Symphyseal bony defects resulting from oncologic resection, trauma, and congenital deformities create tremendous cosmetic and functional handicaps and have remained extremely challenging to surgically reconstruct. This study demonstrates the ability to use arced trifocal distraction osteogenesis to reconstruct anterior mandibulectomy defects in a canine model. This method may provide a satisfactory solution to a difficult problem in human mandibular reconstruction.

Experimental mandibular regrowth by distraction osteogenesis. Long-term results.

The use of gradual distraction to grow bone (distraction osteogenesis) has gained widespread orthopedic acceptance, but has only recently been applied to craniofacial skeletal defects. The use of bifocal distraction osteogenesis to fill experimental segmental mandibular defects with regenerate bone was recently reported. Though all canines in that study demonstrated normal oromandibular function, they were observed for only 4 weeks following defect closure. The study that is now reported describes the long-term (12-month) functional, morphologic, and biomechanical results when bifocal distraction osteogenesis was applied to the same model. In this long-term study, three canines had 2.5-cm unilateral segmental mandibular body defects filled with structurally stable bone using bifocal distraction osteogenesis. These dogs exhibited normal oromandibular function for 1 year following segment regrowth and external fixator removal. Macroscopic and histologic evaluation of the regrown segments revealed a re-formation of the cortical and medullary architecture. Stress testing demonstrated the average ultimate strength of the regrown segment at 53 MPa, which corresponded to 77% +/- 5.7% of normal mandibular bone. The data suggest that clinical trials applying this technique to segmental mandibular reconstruction are warranted.

Hydroxyapatite-coated external-fixation pins. The effect on pin loosening and pin-track infection in leg lengthening for short stature.

Pin loosening and infection are inherent complications of external fixation. This study deals with their effects of using either hydroxyapatite (HA)-coated or uncoated external fixation pins in leg-lengthening procedures on patients of short stature. We used HA-coated pins on one side and uncoated pins on the other (randomly determined) in 28 bilateral lengthenings undertaken in 23 patients. A total of 322 pins was used. The mean implantation time was 530 days and the mean lengthening achieved was 78% of initial bone length. Mean extraction torque was 7611.6 Nmm degree(-1) for HA-coated and 85.4 Nmm degree(-1) for uncoated pins (p < 0.001). The rate of pin loosening was 4% (7/161) for HA-coated and 80% (129/161) for uncoated pins (p < 0.001). There was no statistically significant difference in the incidence of pin-track infection between the two groups. The use of HA coating appears to be an effective method of reducing the incidence of pin loosening in external fixation with a long implantation time and for mechanically highly stressed procedures such as leg lengthening for short stature.

The role of distraction osteogenesis in the reconstruction of the mandible in unilateral craniofacial microsomia.

Laboratory and clinical studies have shown that mandibular distraction is an effective and powerful reconstructive surgical technique. It is safely performed without the need for blood transfusion or bone graft. Because of concomitant expansion of the functional matrix (the associated skin, subcutaneous fat, and muscles of mastication), there is a multidimensional expansion of the lower jaw with minimal, if any, evidence of relapse. Moreover, the surgical reconstruction can be commenced by 2 years of age, and the vector of distraction can be controlled by preoperative design. Finally, the increase in resulting mandibular bone stock will provide more reconstructive options in the future for traditional orthognathic surgical techniques. The technique has been criticized, either for the cutaneous incision for the approach to the mandible or for the scar resulting from the path of the distracting screws. However, with careful placement of the device, the resulting scar can be placed in the lines of minimal tension with a resulting satisfactory scar. It has been assumed that the osteotomy results in interruption of the inferior alveolar nerve. However, questioning of the older patients has failed to detect any change in sensation of the lower lip. The status of the inferior alveolar nerve in the hypoplastic mandible has also never been studied. Insertion of the screws required an area of bone stock that is edentulous, and this finding can make application of the device difficult in some patients. The length of treatment has been criticized--approximately 3 months. However, this is offset by the ease of treatment, the degree of safety, and the reduction in hospital time without the need for blood transfusion or bone graft. The results to date indicate that the technique can be applied to the correction of the milder mandibular deficiencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of distraction osteogenesis by scanning electron microscopy.

A model of bifocal distraction osteogenesis in the canine model was used to assess and quantitate the mineral content of the newly forming bone within the canine mandible. A 2-cm defect was created in the body of the mandible, and after a posterior osteotomy, the transport disk was advanced at 0.25 mm per 8 hours for 21 days and then held in rigid fixation for an additional week. As a control for this study, three additional dogs underwent the same procedure with the exception that the transport disk was not advanced. Electron dispersive spectroscopy analysis was performed on the newly formed regenerate bone and compared with areas of existing cortical bone of both the transport disk and the mandible. In the control model, special note was made of the pericortical callus at the osteotomy site as well as of the regenerative bone that filled the 2-cm defect in the body of the mandible. Calcium/phosphorous ratios were used to assess the composition of the mineralized regions of the mandible. The regenerate bone that filled the defect and the mineralized callus surrounding the site of osteoclasis in the control mandible were significantly different in composition when compared with the regenerate bone that formed during distraction osteogenesis. This suggests that distraction osteogenesis may effect an initial matrix production that is more similar in composition to the mature cortical bone from which it was derived than does periosteal regeneration and filling of an osseous defect.

Assessment of bone formation during osteoneogenesis: a canine model.

Distraction osteoneogenesis, callotasis, has been demonstrated to be an effective means of lengthening long bones. A variation of Ilizarov's technique produces a transport disk from one cut surface of bone within a defect and advances the disk to the opposite surface to close the defect. This process, previously described by Costantino et al. (Arch Otolaryngol Head Neck Surg 1990; 116:535-45), demonstrated bone formation within the distraction site. The precise mechanism of bone formation has not yet been described for the mandible. Four conditioned beagles were studied, with one control dog maintained in neutral fixation and three dogs distracted at 0.25 mm every 8 hours. A two-cm defect was closed, and dogs were kept in fixation for 1 week after closure, after which they were killed. Three sites were evaluated: (1) the distraction seam, (2) the interface of the cortical and distracted bone, and (3) the cortexes at the closed defect. Each site was bisected, and one half was decalcified for immunohistochemical and hematoxylin and eosin pathologic evaluation. The vascular basement membrane was labeled for laminin and type IV collagen. Both of these substances demonstrate the differentiation of the vascular matrix component predisposing primary bone formation. Labels were intense at the distraction seam where intense angiogenesis occurred. No hyalin cartilage was observed at the distraction site, which indicates that the fixation was stable and that ossification occurred primarily without intermediate callous formation. This model demonstrated that osteoclasts within the canine model produce bone through primary bone formation within an angiogenic matrix rich in basement membrane laminin and type IV collagen. Likewise, bone is species specific in mineral composition for dog mandible. Understanding the formation and composition of distracted bone is essential for understanding application of this technique within the clinical setting.

Mandibular lengthening by intraoral distraction using osseointegrated implants.

Mandibular lengthening by distraction osteogenesis is a new method for use in treating congenital deformities or postsurgical bone defects. However, the use of extraoral transcutaneous pins in the mandible has disadvantages, such as facial scars and facial nerve or inferior alveolar nerve injury. The purpose of this study was to establish a new approach to distraction osteogenesis in the mandible by using osseointegrated implants and an intraoral device. Ten adult canines were used for this experiment. After extraction of the teeth and placement of two titanium implants in the left mandible, connection of the intraoral distraction device to the abutments, and corticotomy in the medial portion between implants were performed. Distraction was done at the rate of 1 mm per day to elongate 10 mm in length. Radiographic and histologic examinations showed that successful mandibular lengthening was achieved. New bone was primarily formed by intramembranous ossification and partial endochondral ossification. Titanium implants placed for anchorage of the device remained stable during the course of mandibular lengthening. Study results suggest that the intraoral device using osseointegrated dental implants can be used as a mechanism for distraction osteogenesis in the mandible.

The histologic analysis of distraction osteogenesis of the mandible in rabbits.

The process of bone formation in mandibular lengthening by distraction was studied in 30 rabbits. The mandible was subjected to a corticotomy, held in a neutral position for 2 weeks, and then lengthened at 0.18 mm per 12 hours for 24 days using a unilateral external fixation device (Orthofix M-100). On completion of the distraction, x-ray analysis showed that the distracted gap was filled with callus organized into three zones, namely, two sclerotic zones with a central radiolucent zone. These zones became indistinguishable from the adjacent preexisting mandible at 10 weeks after distraction. Histologically, new bone, which was formed by both intramembranous and endochondral ossification, underwent remodeling and resulted in cortical bone by 8 to 10 weeks after completion of distraction.

Facial skeletal expansion: treatment strategies and rationale.

Forty-three nonconsecutive patients presenting with dentofacial deformity underwent surgical procedures designed intentionally to create skeletal disproportion in the sagittal and/or vertical dimensions. This was accomplished through expansion (enlargement) of the facial skeleton beyond normative standards. At the time of follow-up, which ranged from 14 to 36 months (mean 18.4 months), soft-tissue cephalometric analyses documented facial disproportion to exist in 37 of the 43 patients treated. Thirty-two patients had excessive anterior divergence (facial protrusion) at pogonion, and 17 patients had excessive lower face height as measured from subnasale to menton. All patients were judged to have had a favorable aesthetic outcome. This philosophy of facial skeletal expansion is predicated on two concepts: The first of these is that facial proportions and dimensions beyond those which are considered normal may be extremely attractive in a given individual. Second, the soft-tissue response to skeletal expansion is more favorable and predictable than it is to skeletal contraction in providing for well-supported soft tissues. This treatment planning approach is based on the dynamic interrelationship between the skeletal foundation and the soft-tissue facial mask. It relies on physical examination as the major determinant of aesthetic surgical options.