Induced hypothyroidism alters articular cartilage in skeletally immature miniature swine.

PURPOSE/AIM: Thyroid hormone has been implicated in the normal growth and development of articular cartilage; however, its effect on a disease state, such as hypothyroidism, is unknown. The purpose of this investigation was to compare normal articular cartilage from proximal femurs of immature miniature swine to proximal femurs from hypothyroid-induced immature miniature swine. MATERIALS AND METHODS: Two 11-week-old male Sinclair miniature swine were made hypothyroid by administration of 6-propyl-2-thiouracil (PTU) in their drinking water; two control animals did not receive PTU. At 25 weeks of age, the animals were euthanized and their proximal femurs were fixed and decalcified. Samples were sectioned and analyzed by histology to define extracellular matrix (ECM) structure, immunohistochemistry (IHC) to identify types II and X collagen, and histomorphometry to assess articular cartilage mean total and localized height and cell density. Statistics included nested mixed-effects ANOVA with p ≤ 0.05 considered statistically significant. RESULTS: Compared to controls, hypothyroid articular cartilage demonstrated statistically significant quantitative differences in mean tissue height, mean cell density and type II collagen localized zone height. Qualitative differences in ECM proteoglycans and overall collagen types were also found. Type X collagen was not detected in either hypothyroid or control articular cartilage specimens. CONCLUSIONS: Significant changes in articular cartilage structure in hypothyroid compared to control immature miniature swine suggest that thyroid hormone is critical in the growth and development of articular cartilage. CLINICAL SIGNIFICANCE: Understanding articular cartilage development in immature animal models may provide insight into healing or repair of degenerative human articular cartilage.

Results through skeletal maturity of planned fibular nonunion for the treatment of genu varum in achondroplasia: An observational retrospective study.

Current surgical options for treating genu varum in achondroplasia include tibial and fibular osteotomy and growth modulation using plates and screws. However, a single surgeon consistently treated genu varum using a planned fibular nonunion (PFN). The purpose of this study is to describe his surgical technique and report radiographic and clinical outcomes for the cohort studied.This is an observational retrospective review. The cohort studied included patients with achondroplasia who had PFN surgery for the treatment of genu varum at a young age (<13 years) and was followed through to skeletal maturity. The surgery included meticulous closure of the periosteum over the remaining fibula. The surgery was considered a success if the patient did not require subsequent surgery and had acceptable or improved clinical alignment. Radiographic measures used to determine change in genu varum included the anatomic tibio-femoral angle (aTFA), tibia varus, and tibia-fibula ratio. Clinically, changes in lower limb alignment were defined using a plumb line and 6 categories of alignment ranging from extreme varus to valgus. Statistics were used to validate the plumb line categorization to available radiographic measures. Other appropriate statistical methods were used with P < .05 considered significant.Of the 53 PFN cases (27 patients) included in the study, 34 (64%) did not require subsequent surgery and had acceptable or improved alignment. The average age at surgery and follow-up was 6.1 and 17.0 years, respectively. For the 37 limbs (19 patients) with available radiographs, pre- and post-surgery radiographic measures significantly improved including aTFA (3° varus to 2° valgus, P = .003), tibia varus (2° varus to 3° valgus, P = .004), and the tibia-fibula ratio (0.977 to 1.013, P < .001). Clinically, 32 cases (60%) demonstrated significant improvement by translating into an improved alignment and 9 (17%) remained the same (P < .01). Complications were minimal and insignificant. Failures were readily managed by tibia-fibular osteotomies in adolescence and at maturity.PFN for the treatment of genu varum in young achondroplasia patients significantly improved radiographic and clinical measures of lower limb alignment through skeletal maturity with relatively few complications.

An investigation to validate the equivalence of physes obtained from different anatomic regions in a single animal species: Implications for choosing experimental controls in clinical studies.

Control tissue in studies of various orthopedic pathologies is difficult to obtain and presumably equivalent biopsies from other anatomic sites have been utilized in its place. However, for growth plates, different anatomic regions are subject to dissimilar mechanical forces and produce disproportionate longitudinal growth. The purpose of this study was to compare gene expression and structure in normal physes from different anatomic regions within a single animal species to determine whether such physes were equivalent. Thirteen female New Zealand white rabbits (five 15-week-old and eight 19-week-old animals) were euthanized and physes harvested from their proximal and distal femurs and proximal tibiae. Harvested physes were divided into groups for histological, immunohistochemical (IHC), and reverse transcription-quantitative polymerase chain reaction analyses. All physes analyzed demonstrated no apparent differences in morphology or proteoglycan staining intensity on histological examination or in type II collagen presence determined by IHC study. Histomorphometric measures of physeal height as well as gene expression of type II collagen and aggrecan were found to be statistically significantly equivalent (p < 0.05) among the three different bones from the total number of rabbits. Summary data suggest that the structural similarities and statistical equivalence determined among the various physes investigated in the rabbit validate these tissues in this species for use as surrogate controls by which physeal abnormalities may be compared and characterized in the absence of otherwise normal control tissues. Other species may exhibit the same similarities and equivalence among different physes so that such tissues may serve in like manner as controls for assessing a variety of orthopedic conditions, including those occurring in humans.

Management of bow legs in children: A primary care protocol.

OBJECTIVE: To reduce unnecessary orthopedic referrals by developing a protocol for managing physiologic bow legs in the primary care environment through the use of a noninvasive technique that simultaneously tracks normal varus progression and screens for potential pathologic bowing requiring an orthopedic referral. METHODS: Retrospective study of 155 patients with physiologic genu varum and 10 with infantile Blount`s disease. We used fingerbreadth measurements to document progression or resolution of bow legs. Final diagnoses were made by one orthopedic surgeon using clinical and radiographic evidence. We divided genu varum patients into 3 groups: patients presenting with bow legs before 18 months of age (MOA), patients presenting between 18 and 23 MOA, and patients presenting at 24 MOA or older for analyses relevant to the development of the follow-up protocol. RESULTS: Physiologic genu varum patients walked earlier than average infants (10 months vs 12-15 months; P<.001). Physiologic genu varum patients presenting before 18 MOA demonstrated initial signs of correction between 18 and 24 MOA and resolution by 30 MOA. Physiologic genu varum patients presenting between 18 and 23 MOA demonstrated initial signs of correction between 24 MOA and 30 MOA and resolution by 36 MOA. CONCLUSION: Primary care physicians can manage most children presenting with bow legs. Management focuses on following the progression or resolution of varus with regular follow-up. For patients presenting with bow legs, we recommend a follow-up protocol using mainly well-child checkups and a simple clinical assessment to monitor varus progression and screen for pathologic bowing.

Microarray analysis of slipped capital femoral epiphysis growth plates.

BACKGROUND: Microarray technology has been used to analyze gene expression in patients with and without slipped capital femoral epiphysis (SCFE). METHODS: Proximal femoral physis core biopsies from two patients with SCFE were compared with two control specimens from age-matched patients without SCFE. Extracted RNA from frozen ground samples was subjected to microarray analysis with data tests for statistical significance between SCFE and control tissues. RESULTS: Compared to controls, SCFE samples demonstrated significant up-regulation in gene expression pathways involving physiological defense and inflammatory responses and significant down-regulation in the regulation of cellular physiologic processes, cellular metabolic pathways, and skeletal development pathways including expression of aggrecan and type II collagen, genes affecting physeal structure and integrity. CONCLUSIONS: Up-regulation of inflammatory and immune response pathways in SCFE compared to controls relates to physeal mechanical displacement in SCFE. Globalized down-regulation of several other pathways suggests growth plate weakening. These novel microarray findings further define SCFE etiology.

Fibular Allograft and Demineralized Bone Matrix for the Treatment of Slipped Capital Femoral Epiphysis.

Previous studies documented the use of fibular allograft in the treatment of slipped capital femoral epiphysis (SCFE) with bone graft epiphysiodesis (BGE). This study describes the results of using a 10-mm diameter premilled fibular allograft packed with demineralized bone matrix placed across the physis in an open surgical approach under image intensification. A review identified 45 cases of BGE using fibular allograft and demineralized bone matrix in 34 patients with a diagnosis of SCFE performed by a single surgeon during an 8-year period. Thirty-four cases (25 patients) had at least 1 year of follow-up and were included in the study. Medical records were reviewed for complications, subsequent surgeries, and time to physeal closure. Of the 34 cases included, there were no cases of acute chondrolysis. Complications included 1 case of bone graft extrusion that required surgical replacement and 1 re-slip requiring surgical stabilization. Five cases of avascular necrosis (AVN) were encountered (1 unstable slip with total head AVN, and 4 stable slips with 3 total head and 1 partial head AVN). In 1 patient, small loose bony fragments were noted on postoperative radiographs that appeared outside of the articular surface of the hip and were asymptomatic. Two patients encountered wound healing issues that resolved with appropriate wound care. In light of the occurrence of AVN in stable cases, BGE with autogenous corticocancellous graft is preferable to BGE with autologous fibular graft for the treatment of SCFE. [Orthopedics. 2016; 39(3):e519-e525.].

Partial or non-union after triple arthrodesis in children: does it really matter?

PURPOSE: Triple arthrodesis is a commonly performed salvage procedure to correct hindfoot deformity. Non-union is considered an undesirable radiographic outcome; however, the clinical ramifications of this are not as well defined. The purpose of this study was to determine the incidence of partial or complete radiographic non-union after triple arthrodesis in children and characterize the clinical consequences. METHODS: An IRB-approved retrospective review of triple arthrodesis surgeries in patients less than 16 years of age performed by a single surgeon (DSW) identified 159 cases meeting the inclusion criteria. Plain radiographs were reviewed for bony fusion (defined as over 80 % radiographic bony union of the subtalar, calcaneocuboid, and talonavicular bones) and charts for clinical outcomes (pain, return to activity, and subsequent hindfoot surgeries). Statistics were used to compare the fused and unfused cases, with p < 0.05 considered to be significant. RESULTS: Of the 159 cases included in the study, 9 % did not achieve at least 80 % plain film radiographic union. The fused and unfused groups had similar clinical outcomes. Only one patient required surgery for sequelae of symptoms arising from a pseudoarthrosis related to the triple arthrodesis. The fused and unfused groups were similar in terms of gender and pin removal time, but differed significantly in surgical age and underlying diagnosis. CONCLUSIONS: This is one of the largest case series of pediatric triple arthrodesis surgery presented in the literature. This study demonstrated that good clinical outcomes can be achieved despite the lack of radiographic union after triple arthrodesis surgery in children. LEVEL OF EVIDENCE: IV.

Cartilage hair hypoplasia: characteristics and orthopaedic manifestations.

PURPOSE: Cartilage hair hypoplasia (CHH) is a rare metaphyseal chondrodysplasia characterized by short stature and short limbs, found primarily in Amish and Finnish populations. Cartilage hair hypoplasia is caused by mutations in the RMRP gene located on chromosome 9p13.3. The disorder has several characteristic orthopaedic manifestations, including joint laxity, limited elbow extension, ankle varus, and genu varum. Immunodeficiency is of concern in most cases. Although patients exhibit orthopaedic problems, the orthopaedic literature on CHH patients is scant at best. The objective of this study was to characterize the orthopaedic manifestations of CHH based on the authors' unique access to the largest collection of CHH patients ever reported. METHODS: The authors examined charts and/or radiographs in 135 cases of CHH. We analyzed the orthopaedic manifestations to better characterize and further understand the orthopaedic surgeon's role in this disorder. In addition to describing the clinical characteristics, we report on our surgical experience in caring for CHH patients. RESULTS: Genu varum, with or without knee pain, is the most common reason a patient with CHH will seek orthopaedic consultation. Of the cases reviewed, 32 patients had undergone surgery, most commonly to correct genu varum. CONCLUSION: This paper characterizes the orthopaedic manifestations of CHH. Characterizing this condition in the orthopaedic literature will likely assist orthopaedic surgeons in establishing a correct diagnosis and appreciating the orthopaedic manifestations. It is important that the accompanying medical conditions are appreciated and evaluated.

An operative approach to address severe genu valgum deformity in the Ellis-van Creveld syndrome.

BACKGROUND: The genu valgum deformity seen in the Ellis-van Creveld syndrome is one of the most severe angular deformities seen in any orthopaedic condition. It is likely a combination of a primary genetic-based dysplasia of the lateral portion of the tibial plateau combined with severe soft-tissue contractures that tether the tibia into valgus deformations. Progressive weight-bearing induces changes, accumulating with growth, acting on the initially distorted and valgus-angulated proximal tibia, worsening the deformity with skeletal maturation. The purpose of this study is to present a relatively large case series of a very rare condition that describes a surgical technique to correct the severe valgus deformity in the Ellis-van Creveld syndrome by combining extensive soft-tissue release with bony realignment. METHODS: A retrospective review examined 23 limbs in 13 patients with Ellis-van Creveld syndrome that were surgically corrected by two different surgeons from 1982 to 2011. Seven additional patients were identified, but excluded due to insufficient chart or radiographic data. A successful correction was defined as 10° or less of genu valgum at the time of surgical correction. Although not an outcomes study, maintenance of 20° or less of genu valgum was considered desirable. Average age at surgery was 14.7 years (range 7-25 years). Clinical follow-up is still ongoing, but averages 5.0 years (range 2 months to 18 years). Charts and radiographs were reviewed for complications, radiographic alignment, and surgical technique. The surgical procedure was customized to each patient's deformity, consisting of the following steps: 1. Complete proximal to distal surgical decompression of the peroneal nerve 2. Radical release and mobilization of the severe quadriceps contracture and iliotibial band contracture 3. Distal lateral hamstring lengthening/tenotomy and lateral collateral ligament release 4. Proximal and distal realignment of the subluxed/dislocated patella, medial and lateral retinacular release, vastus medialis advancement, patellar chondroplasty, medial patellofemoral ligament plication, and distal patellar realignment by Roux-Goldthwait technique or patellar tendon transfer with tibial tubercle relocation 5. Proximal tibial varus osteotomy with partial fibulectomy and anterior compartment release 6. Occasionally, distal femoral osteotomy RESULTS: In all cases, the combination of radical soft-tissue release, patellar realignment and bony osteotomy resulted in 10° or less of genu valgum at the time of surgical correction. Complications of surgery included three patients (five limbs) with knee stiffness that was successfully manipulated, one peroneal nerve palsy, one wound slough and hematoma requiring a skin graft, and one pseudoarthrosis requiring removal of hardware and repeat fixation. At last follow-up, radiographic correction of no more than 20° of genu valgum was maintained in all but four patients (four limbs). Two patients (three limbs) had or currently require revision surgery due to recurrence of the deformity. CONCLUSION: The operative approach presented in this study has resulted in correction of the severe genu valgum deformity in Ellis-van Creveld syndrome to 10° or less of genu valgum at the time of surgery. Although not an outcomes study, a correction of no more than 20° genu valgum has been maintained in many of the cases included in the study. Further clinical follow-up is still warranted. LEVEL OF EVIDENCE: IV.

Management of the rigid cavus foot in children and adolescents.

This article reviews historical approaches to the various osteotomies in the treatment of rigid cavus feet in children, with an emphasis on the biplanar nature of historical osteotomies. The Akron dome midfoot osteotomy is performed at the apex of the rigid cavus deformity and allows for maximum correction in any plane, and for varus, valgus, dorsal, plantar, and rotational correction. In that regard, the Akron dome midfoot osteotomy provides the greatest amount of multiplanar correction. It does not, however, provide correction of hindfoot deformities or deformity distal to the neck of the metatarsal.

The effects of hypothyroidism on the proximal femoral physis in miniature swine.

As a potential means of comparing hypothyroidism in humans, this work intended to establish a defined hypothyroid state in immature miniature swine and evaluate specific molecular, cellular, and extracellular responses of their growth plates. Two male, 11-week-old Sinclair miniature swine were given 6-propyl-2-thiouracil (PTU) in their water and two other like animals (controls) were provided water without PTU. Blood levels of thyroid stimulating hormone (TSH), triiodothyronine (T3), and thyroxin (T4) were monitored weekly. At 25 weeks of age, the hind limb proximal femoral physes were harvested and divided into portions for histology and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. Compared to controls, swine administered PTU exhibited increased TSH and decreased T3 and T4 serum levels during the study period, features consistent with a hypothyroid state. Compared to controls, hypothyroid swine exhibited structurally altered physes and demonstrated significantly decreased gene expression of aggrecan (p < 0.05) and type X collagen (p ≤ 0.1). This is the first hypothyroid model established in miniature swine and represents a potentially important advance for understanding the condition in humans, in which, like this swine model, there are changes critical to growth plate molecular biology, biochemistry and structure.

Orthopaedic manifestations of chondroectodermal dysplasia: the Ellis-van Creveld syndrome.

BACKGROUND: Ellis-van Creveld is a dwarfing syndrome transmitted as an autosomal recessive trait. The constant features of the condition include acromelic-micromelic dwarfism, ectodermal dysplasia involving the nails, teeth and gums, postaxial polydactyly of the hands and congenital heart disease. Congenital heart disease affects 50-60 % of all patients and nearly 50 % of patients die by 18 months of age from cardiopulmonary complications. This study is intended to characterise the orthopaedic manifestations of Ellis-van Creveld based on the authors' unique opportunity to interview and examine the largest group of patients to date in the literature. METHODS: Detailed interviews, physical examinations and/or radiographs were available on 71 cases of Ellis-van Creveld syndrome. Data were collected from physical examinations, radiographs, computed tomography (CT) reconstruction and magnetic resonance imaging (MRI) of the knee. Pathoanatomy of the knee was reinforced by the direct surgical observation of 25 limbs surgically managed during adolescence and puberty. RESULTS: A number of interesting clinical and radiographic abnormalities were noted in the upper extremities and lower extremities, but by far the most significant orthopaedic finding was a severe and relentlessly progressive valgus deformity of the knee. Although many patients had difficulties making a "fist" with the hand, no patient reported any functional disability. The severe valgus deformity of the knee is the result of a combination of profound contractures of the iliotibial band, lateral quadriceps, lateral hamstrings and lateral collateral ligament, leading to lateral patellar subluxation and dislocation. The lateral portion of the upper tibial plateau presents with cupping and progressive depression of the lateral plateau, along with severe valgus angulation of the proximal tibia and fibula. A proximal medial tibial exostosis is seen in nearly all cases. CONCLUSION: This is the largest group of Ellis-van Creveld syndrome patients identified in the literature. An understanding of the orthopaedic pathoanatomy of the knee deformity is critical to determining the appropriate surgical management. This paper characterises the orthopaedic manifestations of Ellis-van Creveld syndrome and especially identifies the pathoanatomy of the severe and progressive valgus knee deformity. LEVEL OF EVIDENCE: Level II.

A study in vivo of the effects of a static compressive load on the proximal tibial physis in rabbits.

BACKGROUND: The effect of compression on the physis is generally defined by the Hueter-Volkmann principle, in which decreased linear growth of the physis results from increased compression. This investigation examined whether mechanically induced compression of rabbit physes causes changes in gene expression, cells, and extracellular components that promote physeal resilience and strength (type-II collagen and aggrecan) and cartilage hypertrophy (type-X collagen and matrix metalloprotease-13). METHODS: Static compressive loads (10 N or 30 N) were applied for two or six weeks across one hind limb proximal tibial physis of thirteen-week-old female New Zealand White rabbits (n = 18). The contralateral hind limb in all rabbits underwent sham surgery with no load to serve as an internal control. Harvested physes were divided into portions for histological, immunohistochemical, and quantitative reverse transcription-polymerase chain reaction analysis. Gene expression was statistically analyzed by means of comparisons between loaded samples and unloaded shams with use of analysis of variance and a Tukey post hoc test. RESULTS: Compared with unloaded shams, physes loaded at 10 N or 30 N for two weeks and at 10 N for six weeks showed histological changes in cells and matrices. Physes loaded at 30 N for six weeks were decreased in thickness and had structurally disorganized chondrocyte columns, a decreased extracellular matrix, and less intense type-II and X collagen immunohistochemical staining. Quantitative reverse transcription-polymerase chain reaction analysis of loaded samples compared with unloaded shams yielded a significantly (p ≤ 0.05) decreased gene expression of aggrecan and type-II and X collagen and no significant (p > 0.05) changes in the matrix metalloprotease-13 gene expression with increasing load. CONCLUSIONS: Compressed rabbit physes generate biochemical changes in collagens, proteoglycan, and cellular and tissue matrix architecture. Changes potentially weaken overall physeal strength, consistent with the Hueter-Volkmann principle, and lend understanding of the causes of pathological conditions of the physis.

The use of the reconstruction plate in multiplanar tibial osteotomies in children.

PURPOSE: External fixation and cross-pin fixation appear to be the two most commonly used forms of fixation after a tibial osteotomy in children described in the literature. The purpose of this study is to describe our experience using a properly bent and contoured reconstruction plate for mismatched surfaces after a multiplanar tibial osteotomy. METHODS: A retrospective review was conducted of 37 multiplanar tibial osteotomy surgeries in 23 children performed by a single surgeon using a reconstruction plate for internal fixation. A low fibular osteotomy and tibial osteotomy that required contouring and shaping of the plate were performed in all cases. A proximal tibial osteotomy was performed in 30 cases and a distal osteotomy in seven cases. All cases were reinforced with a long-leg cast. All charts were reviewed for intra- and postoperative complications. The surgery using the reconstruction plate internal fixation was considered to be a success if there was healing of the osteotomy and no hardware failure. RESULTS: A properly bent and contoured reconstruction plate conformed well to the mismatched surfaces after tibial osteotomy. Hardware was removed in all but two cases, on average 7 months after surgery. There were no hardware failures. No child developed a deep wound infection or neurovascular complication, including compartment syndrome. Only two complications in 37 surgeries (5%) were encountered and were typical of any type of internal fixation. One child required an exploratory procedure because of screw extrusion and one child developed a post-plate removal fracture. CONCLUSIONS: The reconstruction plate is very malleable and can be contoured to fit in nearly every direction to accommodate mismatched appositional surfaces. It has been successfully employed in 37 consecutive cases of multiplanar tibial osteotomy in children with relatively few complications, none directly related to the plate.

The 3-dimensional configuration of the typical hip and knee in diastrophic dysplasia.

PURPOSE: Surgical correction of the hip and knee in patients with diastrophic dysplasia is extremely difficult secondary to the markedly distorted pathoanatomy of both the bone and soft tissues. The objective of this study is to provide a 3-dimensional model and carefully and extensively describe the pathoanatomy of the diastrophic hip and knee. METHODS: Three-dimensional computer model reconstructions were developed based on clinical, radiographic, and surgical observations performed "meticulously" by a single surgeon on 110 hips in 55 patients. An additional 13 patients seen by another surgeon were also reviewed. In addition to the clinical and radiographic evaluations, 10 computed tomographic scans were performed of the pelvis and hip areas and 53 arthrograms were done in 13 patients. Sixty-six patients underwent a myriad of operative procedures on the hip and proximal femur. RESULTS: The typical pathoanatomy seen in cases of diastrophic dysplasia reflects the severe and rampantly progressive flexion deformity of the hip and knee with time, and the anatomical aberrations of development of the proximal femur and the knee joint, which are highlighted in our computer model. Replacement arthroplasty at the hip and knee may hold the only solution to adolescents and adults with advanced disease; however, the unavailability of long-term data precludes a reasonable management recommendation. CONCLUSIONS: The disturbed pathoanatomy of the diastrophic dysplasia hip and knee reflects the difficulties in achieving any substantial surgical correction even with customization. This report provides the most extensive 3-dimensional pathoanatomical observations as yet presented in the literature. LEVEL OF EVIDENCE: Level II.

Modified Chrisman-Snook repair for the treatment of chronic ankle ligamentous instability in children and adolescents.

PURPOSE: Chronic ankle ligamentous instability is not uncommonly encountered in children and adolescents. A number of operative procedures have been developed and described in the literature, including variations on the original Chrisman-Snook (CS) repair. The purpose of this study is to describe a modification of the CS repair and report the outcomes of this surgery for the treatment of chronic ankle ligamentous instability in children and adolescents. METHODS: A retrospective review was conducted of 100 consecutive surgeries in 66 children performed by a single surgeon who modified the CS repair using a split peroneus brevis tendon to reinforce the anterior talofibular and calcaneofibular ligaments in chronic ligamentously lax patients. All charts were reviewed for complications. Fifty-three cases had at least a 2-year follow-up and were evaluated for the following outcomes: return to activity, ligamentous laxity, pain, and subsequent sprains. RESULTS: Of the 100 surgeries performed, no patient required repeat ligamentous repair. There were no deep wound infections. There were 10 cases of minor wound healing problems and two cases of temporary nerve dysfunction, one of which resolved without surgical intervention and the other is resolving with no plans for surgical intervention. There were two cases of sural nerve branch entrapment which required subsequent surgery due to neuroma formation. Of the 53 cases with at least a 2-year follow-up, the following outcomes were obtained: all patients returned to full activities of their choice; all but one case maintained ≤45° of ankle inversion postoperatively; all patients were pain free or had only occasional discomfort; and 23% of the ankles experienced subsequent minor sprains, but all were minor and resolved without consequence. CONCLUSIONS: A modification of the CS repair where the split peroneus brevis tendon is used to create ankle stability has been routinely successful in 100 consecutive cases of chronic ligamentous instability in children and adolescents with very few complications.

Multiplanar supramalleolar osteotomy in the management of complex rigid foot deformities in children.

PURPOSE: Residual midfoot and hindfoot deformities in rigidly deformed feet present a very complicated surgical dilemma. A plantigrade foot is desirous for proper lower extremity mechanics in a child with ambulatory potential. In this group of patients, soft tissue procedures are no longer an appropriate option, and well-recognized hindfoot procedures, such as talectomy, have many disadvantages. This study reviews the results obtained using multiplanar supramalleolar osteotomy as a salvage procedure to correct deformities of the complex rigid foot in children. METHODS: A retrospective review was conducted of 27 multiplanar supramalleolar osteotomies in 18 children. The underlying diagnosis of the patients included seven severely rigid idiopathic clubfeet, five arthrogryposis, two myelodysplasia, one Ellis-van Creveld, one Streeter's, one cerebral palsy, and one severe burn contracture. The average age at surgery was 5.6 years, and follow-up averaged 8 years. A successful outcome was deemed a plantigrade foot on physical exam with follow-up of at least 2 years and no subsequent tibial surgeries. All failures were included regardless of the length of follow-up. RESULTS: A plantigrade attitude of the hindfoot was obtainable at the time of surgery in all cases. Eighteen of the 27 feet had a successful outcome. Nine of 27 (33%) feet had recurrence of the foot deformity requiring additional surgery. Time to recurrence averaged 5.7 years (9 months-13 years). Complications from the surgery included four minor wound healing problems, two delayed unions, and one screw recession, all of which healed without consequences. There was no evidence of nonunion, growth plate closure, infection, or fracture above or through screw holes. CONCLUSION: The multiplanar supramalleolar osteotomy appears to be a reasonable salvage procedure for severely scarred and complex rigid foot deformities and can be reinstituted for failures due to remaining growth.

Gene expression in slipped capital femoral epiphysis. Evaluation with laser capture microdissection and quantitative reverse transcription-polymerase chain reaction.

BACKGROUND: Slipped capital femoral epiphysis is a poorly understood condition affecting adolescents. Prior studies have suggested that the etiology may be related to abnormal collagen in the growth plate cartilage, but we are not aware of any investigations analyzing collagen or other structural proteins on a molecular level in the affected tissue. This study was performed to evaluate expression of mRNA for key structural molecules in growth plate chondrocytes of patients with slipped capital femoral epiphysis. METHODS: A core biopsy of the proximal femoral physis was performed in nine patients with slipped capital femoral epiphysis, and the specimens were compared with five specimens from the normal distal femoral and proximal tibial and fibular physes of age-matched patients treated surgically for a limb-length inequality. We utilized laser capture microdissection techniques followed by quantitative reverse transcription-polymerase chain reaction analysis to determine if a change or abnormality in type-II-collagen and/or aggrecan gene expression may be associated with slipped capital femoral epiphysis. With these techniques, we correlated chondrocyte spatial location and gene expression to provide greater insight into this pathological condition and a more complete understanding of growth plate biology in general. RESULTS: Downregulation of both type-II collagen and aggrecan was found in the growth plates of the subjects with slipped capital femoral epiphysis when compared with the levels in the age-matched controls. In eight specimens from affected patients, the level of expression of type-II-collagen mRNA was, on the average (and standard error of the mean), 13.7% +/- 0.2% of that in four control specimens and the aggrecan level averaged only 26% +/- 0.2% of the control aggrecan level. CONCLUSIONS: The decreases that we identified in type-II-collagen and aggrecan expression would affect the quantity, distribution, and organization of both components in a growth plate, but these changes could be associated with either the cause or the result of a slipped capital femoral epiphysis.