Surgery for Spinal Stenosis in Achondroplasia: Causes of Reoperation and Reduction of Risks.

BACKGROUND: Individuals with achondroplasia are prone to symptomatic spinal stenosis requiring surgery. Revision rates are thought to be high; however, the precise causes and rates of reoperation are unknown. The primary aim of this study is to investigate the causes of reoperation after initial surgical intervention in individuals with achondroplasia and spinal stenosis. In addition, we report on surgical techniques aimed at reducing the risks of these reoperations. METHODS: A retrospective review was conducted over an 8-year period of all patients with achondroplasia at a single institution that serves as a large referral center for patients with skeletal dysplasias. Patients with achondroplasia who underwent spinal surgery for stenosis were identified and the need for revision surgery was studied. Data collected included demographic, surgical, and revision details. Fisher exact test was used to determine if an association existed between construct type and the need for revisions. RESULTS: Thirty-three of the 130 (22%) patients with achondroplasia required spinal stenosis surgery. Twenty-four individuals who met the criteria were selected for analysis. The initial spine surgery was at an average age of 18.7 years (SD: 10.1 y). Nine patients (38%) required revision surgeries, and 3 required multiple revisions. Five of 9 (56%) of the revisions had primary surgery at an outside institution. Revision surgeries were due to caudal pseudarthrosis (the distal instrumented segment) (8), proximal junctional kyphosis (PJK) (7), and new neurological symptoms (7). There was a significant association found between construct type and the need for revision ( P =0.0111). The pairwise comparison found that short fusions were significantly associated with the need for revision compared with the interbody group ( P =0.0180). PJK was associated with short fusions when compared with the long fusion group ( P =0.0294) and the interbody group ( P =0.0300). Caudal pseudarthrosis was associated with short fusions when compared with the interbody group ( P =0.0015). Multivariate logistic regression found long fusion with an interbody was predictive of and protective against the need for revision surgery ( P =0.0246). To date, none of the initial cases that had long fusions with caudal interbody required a revision for distal pseudarthrosis. CONCLUSIONS: In patients with achondroplasia, the rate of surgery for spinal stenosis is 22% and the risk of revision is 38% and is primarily due to pseudarthrosis, PJK, and recurrent neurological symptoms. Surgeons should consider discussing spinal surgery as part of the patient's life plan and should consider wide decompression of the stenotic levels and long fusion with the use of an interbody cage at the caudal level in all patients to reduce risks of revision. LEVEL OF EVIDENCE: Level IV-Retrospective case series.

Developing an adolescent and adult Fontan Management Programme.

Patients with single-ventricle CHD undergo a series of palliative surgeries that culminate in the Fontan procedure. While the Fontan procedure allows most patients to survive to adulthood, the Fontan circulation can eventually lead to multiple cardiac complications and multi-organ dysfunction. Care for adolescents and adults with a Fontan circulation has begun to transition from a primarily cardiac-focused model to care models, which are designed to monitor multiple organ systems, and using clues from this screening, identify patients who are at risk for adverse outcomes. The complexity of care required for these patients led our centre to develop a multidisciplinary Fontan Management Programme with the primary goals of earlier detection and treatment of complications through the development of a cohesive network of diverse medical subspecialists with Fontan expertise.

Anatomic Relationship of the Femoral Neurovascular Bundle in Patients With Congenital Femoral Deficiency.

BACKGROUND: Congenital femoral deficiency (CFD) is a rare condition that affects the morphology of the hip and surrounding soft tissues. Bony deformity and distorted muscular anatomy are well known, but no studies have described the relationship of the femoral neurovascular (NV) bundle to surgically relevant anatomic landmarks. The authors compared the location of the femoral NV bundle on the affected side in patients with CFD with the unaffected side. The authors hypothesized that the bundle on the pathologic side would be in an abnormal position relative to the unaffected side. METHODS: Thirty-three patients diagnosed with unilateral CFD who had undergone preoperative magnetic resonance imaging of the pelvis were included in our study. The authors identified the femoral NV bundle on the axial cuts and measured its distance from the anterior superior iliac spine (ASIS), anterior inferior iliac spine (AIIS), and lesser trochanter (LT). Anatomic percent change and absolute measurements were then compared and correlated with associated boney deformities and the Paley classification. RESULTS: The distance from the femoral NV bundle to the ASIS, AIIS, and LT was significantly different compared with the unaffected side. The AIIS absolute distance and AIIS percent change significantly correlated with the neck-shaft angle of the proximal femur. CONCLUSIONS: In patients with CFD, the femoral NV bundle seems to be further from the LT and closer to the AIIS on the affected side when compared with the unaffected side. magnetic resonance imaging may be helpful to understand the course of the femoral NV bundle before reconstruction in patients with CFD; however, the authors recommend identification of the femoral NV bundle before transection of the proximal rectus femoris tendon to provide safe surgical care. LEVEL OF EVIDENCE: Level IV-case-control study of diagnostic studies.

Not All Hip Dysplasias are the Same: Preoperative CT Version Study and the Need for Reverse Bernese Periacetabular Osteotomy.

BACKGROUND: Dysplastic hip may present with acetabular retroversion with or without femoral retroversion. This retroversion, if not accounted for when performing a periacetabular osteotomy (PAO), will lead to anterior hip pain and early osteoarthritis. A reverse PAO involves anteverting the acetabulum while still obtaining lateral coverage. The purpose of this study was to investigate the relationship between rotational malalignment of acetabulum and femur on 2-dimensional computed tomographic (CT) scans of hips that underwent Bernese PAO and its role in the surgical decision making. METHODS: This retrospective, case-control study examined and compared preoperative 2-dimensional CT scans of hips that underwent reverse PAO to the hips that underwent traditional PAO. RESULTS: Twelve hips underwent reverse PAO from 2005 to 2010. Twelve hips were randomly selected from a cohort of 52 hips that underwent traditional PAO during same time period. Hips that underwent reverse PAO showed crossover sign on preoperative radiographs, but not on postoperative radiographs. Crossover sign was negative preoperatively and postoperatively on hips that underwent traditional PAO. The 2 groups were similar in regards to preoperative lateral center-edge angle, acetabular index, and anterior center-edge angle on plain radiographs and showed significant improvement after surgery.On preoperative CT scans both acetabulae and femurs were retroverted in reverse PAO group. Comparison of the 2 groups demonstrated that acetabular version (16.5±4.9 degrees vs. 25.3±5.6 degrees, P=0.001), femoral version (12.8±10.4 degrees vs. 31.9±8 degrees, P<0.001), and McKibbins Instability Index (29.3±11.9 degrees vs. 57.1±9.8 degrees, P<0.001) were significantly lower for the reverse PAO than the traditional PAO group. Anterior Acetabular Sector Angle (determines anterior coverage) was significantly higher in reverse PAO group, 53.1±13.7 degrees versus 39.7±10.4 degrees (P=0.013). CONCLUSIONS: Retroverted acetabulae seem to be associated with reduced femoral version. Given that retroverted acetabulum and retroverted femur have additive effect and increase chances of anterior hip pain, preoperative identification of correct acetabular, and femoral version by CT scan or MRI is necessary to determine which hip need reverse PAO as opposed to traditional PAO. LEVEL OF EVIDENCE: Level III-Therapeutic.

The Etiology of Cam-type Femoroacetabular Impingement: A Cadaveric Study.

BACKGROUND: There is a dearth of literature examining the causes of cam-type femoroacetabular impingement (FAI) and when such morphology appears. The purpose of the current study was to analyze how the ossific portion of the proximal femur develops over time with respect to standard cam-type FAI parameters. METHODS: A collection of 193 femurs from cadavers aged 4 to 21 years were evaluated. The age, sex, ethnicity, and status of the proximal femoral physes (open or closed) of each were recorded. Each specimen was digitally photographed in standardized anteroposterior and modified axial positions. From these photographs, the anterior offset, anterior offset ratio (AOR), and α-angle were determined. A cam lesion was defined as an α-angle >55 degrees on the lateral view. RESULTS: The mean age of the specimens was 17.5±4.2 years. The majority were male (69%) and African American (79%) with closed physes (78%). There were significant differences among discrete age groups with respect to α-angle (P=0.01), anterior offset (P<0.01), and AOR (P<0.01). In addition, younger femurs with open physes had a significantly higher mean α-angle (P<0.01), lower mean anterior offset (P<0.01), and higher mean AOR (P<0.01) compared with older ones with closed physes. Specimens defined as having a cam deformity had a statistically higher α-angle (P<0.01) and lower anterior offset (P<0.01), but there was no difference in AOR values compared with specimens without a cam lesion (P=0.1). CONCLUSIONS: The apparent decline in α-angles as age increases indicates that the traditional α-angle in younger patients measures a different anatomic parameter (ossified femur excluding the cartilaginous portion) than in older patients (completely ossified femur). This suggests that the bony α-angle is inappropriate in the evaluation of cam lesions in the immature physis. The AOR, rather than the anterior offset, may be more accurate in the evaluation of the growing proximal femur. CLINICAL RELEVANCE: This study provides novel insight into, and enhances the understanding of, the development of cam-type FAI.

Wound Closure in Nonidiopathic Scoliosis: Does Closure Matter?

BACKGROUND: Postoperative wound complications after posterior spinal fusion are difficult to manage. The incidence in the nonidiopathic patient population is significantly higher than the adolescent idiopathic population. A comparison of wound complications after posterior spinal fusion for nonidiopathic scoliosis between the utilization of the orthopaedic surgical team at the time of closure performing a nonstandardized wound closure versus a plastic surgeon with a plastic multilayered closure technique and rotational flap coverage when needed had not previously been evaluated. The purpose of this study was to compare the complication rate between nonstandardized and plastic multilayered closure of the surgical incision in patients undergoing posterior spinal fusion for nonidiopathic scoliosis. METHODS: The charts of 76 patients with a primary diagnosis of scoliosis associated with a syndrome or neuromuscular disease and who underwent a posterior spinal fusion were reviewed. Forty-two patients had their incisions closed using the nonstandardized technique and 34 using the plastic multilayered technique. These 2 groups were compared for age, sex, primary diagnosis, number of levels fused, estimated blood loss, number of units transfused, operating room time, wound complication, and return to operating room. RESULTS: The wound complication rate in the nonstandardized closure group was 19% (8/42) compared with 0% (0/34) in the plastic multilayered closure group (P=0.007). The unanticipated return to the operating room rate was 11.9% (5/42) for the nonstandardized closure patients versus 0% (0/34) for the plastic multilayered closure patients (P=0.061). CONCLUSIONS: The use of the plastic multilayered closure technique in this patient population is important in an effort to decrease postoperative wound complications. The ability of the surgical team to decrease the infection rate of nonidiopathic scoliosis cannot be overstated. The method of wound closure plays a major role in lowering this incidence. LEVEL OF EVIDENCE: Level III-therapeutic.

Current Practice in the Management of Slipped Capital Femoral Epiphysis.

BACKGROUND: The most widely used treatment for slipped capital femoral epiphysis (SCFE) is in situ fixation. In an attempt to reduce the chances of impingement, osteoarthritis, and osteonecrosis, surgeons have started adopting newer surgical techniques. The purpose of this study was to determine the current pattern of treating SCFE. METHODS: A questionnaire was sent electronically to all of the members of the Pediatric Orthopaedic Society of North America. The data were analyzed dividing surgeons into academic versus private practice, years of practice, and number of SCFEs treated per year. RESULTS: Of 990 members, 277 (28%) responded to the survey.Type of practice (academic, n=181 vs. private, n=51): For unstable severe SCFE, surgeons in academic practice use the surgical hip dislocation (SHD) approach significantly more frequently (35.7% vs. 14.9%; P=0.02). A radiolucent table is used significantly more frequently in academic practice for both stable (50.6% vs. 29.8%; P=0.01) and unstable (39.6% vs. 15.2%; P=0.002) SCFE. Fully threaded cannulated screws (44.4% vs. 27.1%; P=0.03), open capsular decompression (63.9% vs. 32.4%; P=0.001), contralateral pinning (79% vs. 58.7%; P=0.005), and postoperative magnetic resonance imaging (MRI) (15.5% vs. 3.9%; P=0.03) are significantly more frequent in academic practice.Years of practice (≤15 y, n=124 vs. >15 y, n=140): For severe stable SCFE, surgeons practicing for ≤15 years do acute osteotomies significantly less frequently (1.8% vs. 9%; P=0.004) and perform SHD significantly more frequently (20.2% vs. 8.2%; P=0.004). For unstable moderate SCFE, SHD is utilized significantly more frequently by surgeons ≤15 years in practice (29.8% vs. 16.5%; P=0.04). Bilateral frog-leg lateral views (86.4% vs. 73.7%; P=0.04), preoperative MRI (36.1% vs. 20.6%; P=0.006), open capsular decompression (69.3% vs. 51.7%; P=0.01) are significantly more frequent among surgeons ≤15 years in practice.Number of SCFE treated per year (<10, n=129 vs. ≥10, n=136): For unstable severe SCFE, surgeons treating ≥10/y perform SHD significantly more frequently (38.6% vs. 26.1%; P=0.02) and do in situ fixation with manual reduction significantly less frequently (11.8% vs. 21.8%; P=0.02). Radiolucent table (54.3% vs. 38%; P=0.01), 7.5 mm screw versus 6.5 mm (62% vs. 45.4%; P=0.01), contralateral pinning (78.9% vs. 67.8%; P=0.04), postoperative MRI (17.6% vs. 9.3%; P=0.04), and postoperative computed tomography (14.7% vs. 7%; 0.04) are significantly more frequent among surgeons doing ≥10/y. Elective implant removal is more common among surgeons treating <10/y (16.2% vs. 6.9%; P=0.02). CONCLUSIONS: Treatment of SCFE varies significantly depending on the surgeon's type of practice, years in practice, and numbers treated per year. Surgeons in academic practice, surgeons with ≤15 years in practice, and surgeons treating greater number of SCFEs are more likely to use SHD to acutely reduce the slip.

A Predictive Risk Index for 30-day Readmissions Following Surgical Treatment of Pediatric Scoliosis.

BACKGROUND: Pediatric scoliosis often requires operative treatment, yet few studies have examined readmission rates in this patient population. The purpose of this study is to examine the incidence, reasons, and independent risk factors for 30-day unplanned readmissions following scoliosis surgery. METHODS: A retrospective analysis of the American College of Surgeons National Surgical Quality Improvement-Pediatric database from 2012 to 2013 was performed. Patients undergoing spinal arthrodesis for progressive infantile scoliosis, idiopathic scoliosis, or scoliosis due to other medical conditions were identified and divided between 2 groups: patients with unplanned 30-day readmissions (Readmitted) and patients with no unplanned readmissions (Non-Readmitted). Multivariate logistic regression models were created to determine independent risk factors for readmissions. RESULTS: A total of 3482 children were identified, of which 120 (3.4%) had an unplanned readmission. A majority of patients had a readmission due to a surgical site complication regardless of scoliosis etiology. Risk factors for readmission included obesity (P<0.001) and posterior fusion of 13 or more vertebrae (P=0.029) for idiopathic scoliosis, impaired cognition (P=0.009) for progressive infantile scoliosis, and pelvic fixation (P=0.025) and American Society of Anesthesiologist ≥3 (P=0.048) for scoliosis due to other conditions. CONCLUSIONS: We present 30-day readmissions risk factors based on independent patient and procedural risk factors. This may be useful in the clinical management of patients following scoliosis surgery, specifically for the role of preoperative and predischarge risk stratification.

Management of idiopathic and nonidiopathic flatfoot.

Flatfoot in a child may be normal before development of the arch, but the prevalence decreases with age. Treatment is indicated only in the presence of pain and should begin with nonsurgical management options such as stretching of the Achilles tendon and the use of soft shoe orthotics. If pain persists, a modified Evans procedure, together with additional procedures to address forefoot supination, can be successful in correcting deformity and addressing pain. A thorough understanding of the pathology and correction desired will help minimize complications and recurrence. If neuromuscular pathology is present, treatment principles are altered and greatly depend on the severity of the deformity, the association of tibialis posterior spasticity, and ambulatory status. In mild to moderate pathology in walking patients with cerebral palsy, osteotomies can be successful. Various forms of arthrodesis can decrease recurrence when the deformity is severe in a nonambulatory patient with cerebral palsy and a symptomatic valgus foot deformity. In cases of collagen disorders, where soft-tissue laxity complicates management, deformity correction may be of higher importance. Overall alignment always should be evaluated and corrected when necessary to optimize the outcome in patients with valgus foot deformities. The successful treatment of flexible or rigid flatfoot deformity must take into account underlying pathology to optimize outcomes.

Peroneal Nerve Decompression in Patients with Multiple Hereditary Exostoses: Indications, Complications, and Recurrence.

BACKGROUND: To our knowledge, there have been no studies examining peroneal nerve decompression and proximal fibular osteochondroma excision exclusively in patients with multiple hereditary exostoses (MHE). The purpose of this study was to evaluate the indications, complications, and recurrence associated with nerve decompression and proximal fibular osteochondroma excision in patients with MHE. METHODS: The records on patients with MHE undergoing peroneal nerve decompression from 2009 to 2023 were retrospectively reviewed. Indications, clinical status, surgical technique, recurrence, and complications were recorded and were analyzed using the Fisher exact test, logistic regression, and the Kaplan-Meier method. RESULTS: There were 126 limbs identified in patients with MHE who underwent peroneal nerve decompression. The most common indications were pain over the proximal fibula, tibialis anterior and/or extensor hallucis longus weakness, and dysesthesias and/or neuropathic pain. Seven cases experienced postoperative foot drop as a complication of the decompression and osteochondroma excision. Logistic regression found significant relationships between complications and excision of anterior osteochondromas (odds ratio [OR], 5.21; p = 0.0062), proximal fibular excision (OR, 14.73; p = 0.0051), and previous decompression (OR, 5.77; p = 0.0124). The recurrence rate was 13.8%, and all recurrences occurred in patients who were skeletally immature at the index procedure. The probability of skeletally immature patients not experiencing recurrence was 88% at 3 years postoperatively and 73% at 6 years postoperatively. CONCLUSIONS: Indications for peroneal nerve decompression included neurologic symptoms and pain. The odds of a complication increased with excision of anterior osteochondromas and previous decompression. Recurrence of symptoms following decompression and osteochondroma excision was found exclusively in skeletally immature patients. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Hip flexion contracture and diminished functional outcomes in cerebral palsy.

BACKGROUND: Hip flexion contracture (HFC) in the ambulatory child with cerebral palsy (CP) may impair function and lead to deteriorations in health-related quality of life. Furthermore, increasing HFC may lead to increasing disability. However, the association between passive range of motion and the measures of function and well-being is unclear. This study was designed to determine whether increasing HFC is associated with functional outcome. METHODS: A total of 181 children, with an average age of 14.0 ± 10.2 years, were evaluated as part of a multicenter prospective data collection of patients with ambulatory CP. Measurements of HFC were recorded, and patients were evaluated using walking score from Gillette Functional Assessment Questionnaire (FAQ), Gross Motor Function Measure (GMFM), and the Pediatric Outcome Data Collection Instrument (PODCI). Patients were grouped on the basis of severity of HFC: group A, 0 to 14 degrees; group B, 15 to 29 degrees; and group C ≥ 30 degrees. Associations were examined using the Spearman correlation. RESULTS: There was an inverse association between degree of HFC and FAQ walking score (P<0.01, ρ=-0.25). Similarly, there was an inverse association between the degree of HFC and GMFM parts D (P<0.001, ρ=-0.31) and E (P<0.001, ρ=-0.32). Lastly, the PODCI domains of global function, mobility, and physical function also showed an inverse association with degree of HFC (P<0.001, ρ=-0.24). CONCLUSIONS: As surgeons treating children with CP, we often rely on joint measurements as an indirect measure of function. This study of children with ambulatory CP suggests that increased HFC from the physician's perspective is associated with deterioration in function from a patient and a therapist's perspective. LEVEL OF EVIDENCE: Level II, prospective study.

Chromosome 21-derived microRNAs provide an etiological basis for aberrant protein expression in human Down syndrome brains.

Down syndrome (DS), or Trisomy 21, is the most common genetic cause of cognitive impairment and congenital heart defects in the human population. Bioinformatic annotation has established that human chromosome 21 (Hsa21) harbors five microRNA (miRNAs) genes: miR-99a, let-7c, miR-125b-2, miR-155, and miR-802. Our laboratory recently demonstrated that Hsa21-derived miRNAs are overexpressed in DS brain and heart specimens. The aim of this study was to identify important Hsa21-derived miRNA/mRNA target pairs that may play a role, in part, in mediating the DS phenotype. We demonstrate by luciferase/target mRNA 3'-untranslated region reporter assays, and gain- and loss-of-function experiments that miR-155 and -802 can regulate the expression of the predicted mRNA target, the methyl-CpG-binding protein (MeCP2). We also demonstrate that MeCP2 is underexpressed in DS brain specimens isolated from either humans or mice. We further demonstrate that, as a consequence of attenuated MeCP2 expression, transcriptionally activated and silenced MeCP2 target genes, CREB1/Creb1 and MEF2C/Mef2c, are also aberrantly expressed in these DS brain specimens. Finally, in vivo silencing of endogenous miR-155 or -802, by antagomir intra-ventricular injection, resulted in the normalization of MeCP2 and MeCP2 target gene expression. Taken together, these results suggest that improper repression of MeCP2, secondary to trisomic overexpression of Hsa21-derived miRNAs, may contribute, in part, to the abnormalities in the neurochemistry observed in the brains of DS individuals. Finally these results suggest that selective inactivation of Hsa21-derived miRNAs may provide a novel therapeutic tool in the treatment of DS.

miR-1 overexpression enhances Ca(2+) release and promotes cardiac arrhythmogenesis by targeting PP2A regulatory subunit B56alpha and causing CaMKII-dependent hyperphosphorylation of RyR2.

MicroRNAs are small endogenous noncoding RNAs that regulate protein expression by hybridization to imprecise complementary sequences of target mRNAs. Changes in abundance of muscle-specific microRNA, miR-1, have been implicated in cardiac disease, including arrhythmia and heart failure. However, the specific molecular targets and cellular mechanisms involved in the action of miR-1 in the heart are only beginning to emerge. In this study we investigated the effects of increased expression of miR-1 on excitation-contraction coupling and Ca(2+) cycling in rat ventricular myocytes using methods of electrophysiology, Ca(2+) imaging and quantitative immunoblotting. Adenoviral-mediated overexpression of miR-1 in myocytes resulted in a marked increase in the amplitude of the inward Ca(2+) current, flattening of Ca(2+) transients voltage dependence, and enhanced frequency of spontaneous Ca(2+) sparks while reducing the sarcoplasmic reticulum Ca(2+) content as compared with control. In the presence of isoproterenol, rhythmically paced, miR-1-overexpressing myocytes exhibited spontaneous arrhythmogenic oscillations of intracellular Ca(2+), events that occurred rarely in control myocytes under the same conditions. The effects of miR-1 were completely reversed by the CaMKII inhibitor KN93. Although phosphorylation of phospholamban was not altered, miR-1 overexpression increased phosphorylation of the ryanodine receptor (RyR2) at S2814 (Ca(2+)/calmodulin-dependent protein kinase) but not at S2808 (protein kinase A). Overexpression of miR-1 was accompanied by a selective decrease in expression of the protein phosphatase PP2A regulatory subunit B56alpha involved in PP2A targeting to specialized subcellular domains. We conclude that miR-1 enhances cardiac excitation-contraction coupling by selectively increasing phosphorylation of the L-type and RyR2 channels via disrupting localization of PP2A activity to these channels.

Pelvic positioning creates error in CT acetabular measurements.

BACKGROUND: CT allows for accurate measurement of acetabular orientation and shape, but malpositioning of the pelvis may lead to measurement variance. PURPOSE: We therefore sought to determine: (1) whether acetabular anteversion measurements using the femoral head centers differed from those using the posterior ischia, and (2) the extent to which changing obliquity, rotation, and tilt of a pelvis in a CT scanner affected the measurement of acetabular variables. METHODS: A radiopaque human pelvis model with articulated hips was suspended from a plastic sheet as part of an adjustable frame. Changes in the transverse and sagittal planes created rotation and tilt, while rotating the frame in the coronal plane created obliquity. CT scans were obtained, varying the combinations of obliquity, rotation, and tilt by intervals of 5°, up to 20°. Acetabular anteversion (AA), anterior acetabular sector angle (AASA), posterior acetabular sector angle (PASA), and horizontal acetabular sector angle (HASA) were measured. RESULTS: The two methods for measuring AA yielded values differing by 1° to 4° but correlated (r = 0.981) across the spectrum of pelvis positioning. Pelvic obliquity and tilt were linearly associated with changes in the measurements. For each 1°-increase in pelvic obliquity, AA changed -0.4°, and AASA, PASA, and HASA changed 1.93°, 0.99°, and 2.80°, respectively. For each 1°-increase in pelvic tilt, AA changed 0.8°, and AASA, PASA, and HASA changed -1.07°, 0.52°, and -0.51°, respectively. Rotation had no affect on the variables. CONCLUSIONS: Small changes in pelvic obliquity and tilt were associated with variances in acetabular measurements. The measured changes were directly proportional to the changes in obliquity and tilt, and were additive. Pelvic rotation created no changes in measurement.

Novel Approach to Improving Knee Range of Motion in Arthrogryposis with a New Working Classification.

Arthrogryposis multiplex congenita (AMC) is a rare condition defined as contrac-tures in multiple joints. Surgical interventions for severe knee flexion contractures have included posterior release, distraction and extension with external fixation and distal femoral extension osteotomies. These operations have been able to achieve knee extension, but not increase the range of motion. The purpose of this study was to review our experience with peroneal nerve decompression, posterior knee release and proximal femoral shortening. We retrospectively reviewed the medical charts and radiographs of all patients with a diagnosis of arthrogryposis who underwent aforementioned procedure. There were 39 patients with 73 knees included in the analysis with a mean follow-up of 21 months. The mean preoperative arc of motion was 45° and last followup arc of motion was 79° (p < 0.0001). The mean last followup flexion contracture was 8° (p < 0.0001). Additional subanalyses were performed on those with followup greater than 24 months and those with flexion contractures >60°; there were no differences found in these groups. This study demonstrates that it is possible to achieve a functional range of motion of the knees in patients with AMC while improving ambulatory function.

Lengthening the Lower Extremities of Children with Ollier's and Maffucci's Enchondromatosis Using Implantable Lengthening Nails.

There are multiple forms of enchondromatosis with Ollier's and Maffucci's being the most prevalent types. Limb length discrepancy is a common problem in patients with Ollier's and Maffucci's enchondromatosis. There are multiple reports about lengthening bones in patients with enchondromatosis using external fixators. However, there are no case series regarding the use of implantable lengthening technology. The purpose of this paper is to describe our experience with implantable nail lengthening in patients with enchondromatosis. A retrospective chart and radiographic review of patients with enchondromatosis who underwent implantable nail limb lengthening was performed. Seven patients with 14 bony segments were reviewed. A total of 11/14 lengthenings were completed without difficulty. There were no issues in terms of fixation location in patients with Ollier's disease. One patient with Maffucci's syndrome experienced migration of the nail during two lengthenings due to a combination of intralesional fixation and preconsolidation. One patient with Ollier's disease developed a knee extension contracture requiring manipulation under anesthesia. No other complications were recorded. The use of implantable nail lengthening to resolve limb length discrepancies in patients with Ollier's disease appears to be safe and effective.

Prediction of Radial Head Subluxation and Dislocation in Patients with Multiple Hereditary Exostoses.

BACKGROUND: Multiple hereditary exostoses (MHE) is a rare bone disease that results in growth of benign cartilage-capped tumors and a number of skeletal deformities. Forearm deformities are present in up to 60% of patients with MHE, and radial head subluxation or dislocation occurs in 20% to 30%. Radial head subluxation/dislocation results in a shortened forearm and loss of motion. The purpose of this study was to identify radiographic variables that are most predictive of radial head subluxation/dislocation in an effort to determine the need for prophylactic treatment. METHODS: We retrospectively reviewed the cases of consecutive patients with MHE treated in our center between April 2007 and December 2019. Radiographic measurements included the presence or absence of distal ulnar osteochondromas, total ulnar bow, total radial bow, and percent ulnar length. Participants were separated into 3 groups based on the status of the radial head: located, subluxated, and dislocated. Radiographic measurements were compared using a Kruskal-Wallis H test with Dunn post-hoc analysis. A prediction model was run using a binomial logistic regression, and a prediction matrix was created. RESULTS: A total of 88 patients were included in the study. There were significant differences in the located group compared with the dislocated group in terms of pronation, supination, and extension. The percent ulnar length, total ulnar bow, and total radial bow differed significantly between the located and dislocated groups (p < 0.0001); however, in the binomial regression analysis, only the percent ulnar length and total ulnar bow could be used to distinguish between the located group and the subluxated/dislocated group. Both of these measurements were significant predictors of subluxation/dislocation. There was no radial head subluxation/dislocation in patients with an ulnar bow of <17°. CONCLUSIONS: The data indicate that total ulnar bow and percent ulnar length are good predictors of radial head subluxation/dislocation. These 2 parameters can be utilized to monitor forearm deformity and guide timing for prophylactic treatment. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical Practice Guideline by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America: 2021 Guideline on Diagnosis and Management of Acute Hematogenous Osteomyelitis in Pediatrics.

This clinical practice guideline for the diagnosis and treatment of acute hematogenous osteomyelitis (AHO) in children was developed by a multidisciplinary panel representing Pediatric Infectious Diseases Society (PIDS) and the Infectious Diseases Society of America (IDSA). This guideline is intended for use by healthcare professionals who care for children with AHO, including specialists in pediatric infectious diseases, orthopedics, emergency care physicians, hospitalists, and any clinicians and healthcare providers caring for these patients. The panel's recommendations for the diagnosis and treatment of AHO are based upon evidence derived from topic-specific systematic literature reviews. Summarized below are the recommendations for the diagnosis and treatment of AHO in children. The panel followed a systematic process used in the development of other IDSA and PIDS clinical practice guidelines, which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Orthopaedic manifestations of neurofibromatosis type 1.

Neurofibromatosis type 1 (NF-1) is an autosomal dominant disease that affects 1 in 3,000 persons worldwide. Café-au-lait macules and peripheral nerve sheath tumors (ie, neurofibromas) are the most commonly recognized manifestations of NF-1. However, NF-1 affects multiple organ systems, and a multidisciplinary approach to treatment is required. Management of the orthopaedic manifestations of NF-1 is often difficult. The most complex manifestations are scoliosis (dystrophic and nondystrophic), congenital pseudarthrosis of the tibia, and problems related to soft-tissue tumors. Metabolic bone disease is common; many patients are frankly osteopenic, which further complicates treatment. Dystrophic scoliosis, which may be caused by either bony dysplasia or intraspinal pathology, is characterized by early presentation and rapid progression. Pseudarthrosis is common even after instrumented fusion. Nondystrophic scoliosis tends to behave like adolescent idiopathic scoliosis, although it may present earlier and is associated with a higher rate of pseudarthrosis. Congenital pseudarthrosis of the tibia is a long-bone dysplasia that afflicts patients with NF-1. Management of this osseous deformity is challenging. Failure to achieve union and refracture are common.

Peripheral arthropathy in hereditary sensory and autonomic neuropathy types III and IV.

BACKGROUND: To determine the features of the underlying destructive arthropathy in the peripheral joints of children with hereditary sensory and autonomic neuropathy (HSAN) type III and to compare and contrast this to the arthropathy noted in HSAN type IV, as both groups experience decreased pain perception. METHODS: From a database of 547 patients with HSAN type III and 32 patients with HSAN type IV, we performed a retrospective chart review and radiographic analysis of all patients who presented with joint swelling and deformity. Underlying joint pathology was classified as either osteonecrosis or Charcot arthropathy. RESULTS: In the HSAN type III population, 44 (8%; 22 males and 22 females) of the 547 patients had clinical evidence of arthropathy. In 42 patients, 48 joints demonstrated radiographic evidence of osteonecrosis; 45 (94%) of the 48 joints with osteonecrosis occurred in the lower extremity. In each case of osteonecrosis of the knee (n = 19), isolated involvement of the lateral distal femoral condyle was seen consisting of varying sizes of posterolateral osteochondral fragmentation. In the 32 patients comprising the HSAN type IV population, 18 (56%) were found to have radiographic findings consistent with Charcot arthropathy in a total of 30 affected joints. One patient demonstrated Charcot arthropathy of the spine and subsequent progressive spondylolisthesis. Nine patients (12 joints) also demonstrated osteomyelitis. CONCLUSIONS: In patients with HSAN type III, osteonecrosis is the initial lesion preceding destructive arthropathy. Osteonecrosis and osteochondral fragmentation were always isolated at the lateral distal femoral condyle in the knee. This pathology may be amenable to surgical reconstruction and fixation to stabilize the knee and prevent further degeneration. Hereditary sensory and autonomic neuropathy type IV was most commonly associated with Charcot arthropathy or joint subluxation and dislocation. Late secondary changes at the articular surface may make radiographic distinction difficult. Charcot arthropathy affected both sides of the involved joint with evidence of collapse and fragmentation. With osteonecrosis, the articular process was found to be more focal.