Vague Presentation of Cat Scratch Disease in a Child.

Background: Prolonged fever for more than a week or fever of unknown origin in pediatric patients with or without soft tissue infection should raise suspicion for Bartonella henselae infection. Case Report: A 10-year-old female presented to urgent care with a "bug bite" on the left ring finger, cough, and 2 to 3 days of low-grade fever. Ten days later, her symptoms progressed to soft tissue swelling of the left elbow without fracture on radiograph. Magnetic resonance imaging revealed multiple reniform masses with avid contrast enhancement consistent with suppurative adenitis. She was admitted for irrigation and debridement. The patient underwent surgical debridement with removal of infected lymph nodes. Histology revealed necrotizing granulomatous lymphadenitis. Polymerase chain reaction was positive for B henselae. Antibody titer revealed B henselae immunoglobulin G titer of 1:512 (reference, 1:64), and negative immunoglobulin M titers were indicative of mature immune response. The patient was treated with azithromycin 250 mg tablets twice daily for 3 days followed by 3 days of the 250 mg tablet once daily. Follow-up showed resolution of infection without symptoms concerning for visceral organ infection. Conclusion: While the patient's initial presentation was vague, a complete history, quick follow-up, and decisive intervention prevented significant sequelae such as visceral organ involvement.

Patellar Dislocation and Fracture After Medial Patellofemoral Ligament Reconstruction in a Patient With Osteogenesis Imperfecta.

Background: Patellar instability is a common orthopedic condition in the pediatric population. Many factors contribute to patellar instability, including trochlear dysplasia. However, patellar instability and its treatments are not well documented in the literature for patients with osteogenesis imperfecta. Case Report: After medial patellofemoral ligament (MPFL) reconstruction, a 17-year-old male with osteogenesis imperfecta had a patellar dislocation that resulted in a patellar fracture. The patient subsequently had a revision of his MPFL reconstruction, and at 2½ years postoperation has had no episodes of recurrent patellar instability. Conclusion: The combination of bone fragility, trochlear dysplasia, and strength of the allograft used for MPFL reconstruction compared to the patient's bone strength led to dislocation and patellar fracture. Research into alternative methods for patellar fixation and postoperative physical therapy protocols for patients with osteogenesis imperfecta is needed. Special considerations must be made for this patient population.

Arthroscopic Saucerization of a Symptomatic Posterior Horn Tear in a Discoid Medial Meniscus.

Background: Discoid medial meniscus is an extremely rare congenital anatomic variant with an estimated incidence of 0.12%. Arthroscopic meniscal saucerization and repair are reserved for symptomatic tears only. We present a case of discoid medial meniscus tear, outline the surgical arthroscopic technique used for treatment, and compare several surgical approaches. Case Report: An 18-year-old male presented with left knee pain and mechanical symptoms present for 2 years. Physical examination showed stability to both varus and valgus stresses with absence of locking or catching on McMurray testing. Magnetic resonance imaging confirmed discoid medial meniscus with a horizontal oblique tear of the posterior horn. The patient underwent saucerization of the left discoid medial meniscus and medial meniscus repair. Conclusion: Discoid medial meniscus predisposes individuals to meniscal tears that often require operative management. Careful consideration of surgical approach can help to optimize patient outcomes while minimizing the risk of iatrogenic injury.

A Rare Case of Bruck Syndrome Type 2 in Siblings With Broad Phenotypic Variability.

Background: Bruck syndrome is a rare autosomal recessive condition that presents with many of the symptoms of osteogenesis imperfecta. In addition to defective type I collagen, manifesting as bone fragility, osteoporosis, and blue sclera, Bruck syndrome is additionally characterized by arthrogryposis with pterygia. Joint contractures are frequently bilateral and severe. Case Report: We report the medical record and radiographic data for 2 siblings with Bruck syndrome type 2-a male (age 6 years) and a female (age 5 years)-born to nonaffected parents. The male has experienced more than 45 fractures, developed severe scoliosis, and has debilitating flexion contractures. The female has minimal flexion contractures, a history of 15 fractures, and severe scoliosis. Conclusion: The dramatic difference between the phenotypes of these 2 cases is significant because it is the largest known variability of phenotypic presentation in siblings. Previous cases of siblings with differing presentations at birth have been reported, but the extent of these differences is not as extreme as in our cases. Because Bruck syndrome presents similarly to osteogenesis imperfecta and could be clinically mistaken for a form of osteogenesis imperfecta if contractures are minimal, a reasonable focus for research efforts is the development of genetic diagnostic protocols for osteogenesis imperfecta with the goal of ruling out Bruck syndrome.

Long-term Results of Spine Stapling for AIS to Skeletal Maturity and Beyond.

BACKGROUND: We looked at long-term follow-up of spine stapling with Nitinol Staples. This was a cohort of all adolescent idiopathic scoliosis (AIS) patients with curves at high risk to progress based on curve magnitude, premenarchal status in all females, failure of brace treatment, and skeletal immaturity. METHODS: This is a single surgeon retrospective review of consecutive AIS patients treated with Nitinol staples for progressive scoliosis. Fourteen patients, 16 curves from 2005 to 2008 were eligible. Minimum curve for stapling was 30 degrees. Standard preoperative, intraoperative, and postoperative data were collected. All patients were followed for a minimum of 36 months and to skeletal maturity. Three groups were: improved (group 1), correction of any amount; minimal progression (group 2), progression ≤10 degrees; and failure (group 3), ≥10 degrees of progression. RESULTS: A total of 13 thoracic curves and 2 compensatory lumbar curves met the inclusion criteria (94%). Average follow-up was 61 months. The mean preoperative main thoracic curve was 35 degrees. All but 1 patients progressed at least 9 degrees in a brace prior to stapling. Females were all premenarchal, 10 patients were Risser 0 and 3 Risser 1. The average number of vertebrae stapled per curve was 6. Group 1 included 6 curves (40%). Group 2, 5 curves (33%). Group 3, 4 curves (27%). Three patients went on to uncomplicated fusion. Final curve measurement at the end of follow-up or before fusion (P=0.0037), curve progression (P≤0.001), and percentage of coronal correction on first postoperative standing radiograph (P=0.042) were the significant differences between groups 1+2 (successful) versus group 3 (failures). In total, 73% of this group either progressed ≤10 degrees or improved. CONCLUSIONS: This is the first study that follows AIS patients treated with spine stapling to skeletal maturity. Staples likely changed natural history in some of our patients. Initial percentage of correction on first standing postoperative PA x-rays was the only predictor of success. Stapling was safe without any long-term complications. LEVEL OF EVIDENCE: Level III-retrospective study.

Autograft vs Allograft Comparison in Pediatric Medial Patellofemoral Ligament Reconstruction.

Background: Patella instability and medial patellofemoral ligament (MPFL) injury are frequently encountered in pediatric patients. MPFL reconstruction is often chosen to treat this condition with good results; however, no consensus has been reached about which graft or technique to use. The purpose of this study was to evaluate the differences in graft survivorship, clinical outcomes (assessed with Kujala scores), and cost between autograft and allograft usage in MPFL reconstruction in pediatric patients. Methods: In this retrospective review of patients who underwent MPFL reconstruction between 2012-2015, autograft gracilis tendon was used for Group 1, and allograft gracilis tendon was used for Group 2. Outcomes were graft survivorship, postoperative Kujala scores, operative time, costs, graft size, and tibial tubercle-trochlear groove distance. Results: Fifty-six patients were included in this study, 21 in Group 1 and 35 in Group 2. No differences in age, sex, or chronicity were seen between the groups. Patients in Group 1 had longer operative times (134.5 minutes vs 97.3 minutes, P=0.0002), higher rates of graft failure (28.6% vs 0%, P=0.0037), and lower Kujala scores (80.3 vs 92.1, P=0.0032) compared to Group 2. All graft failures occurred in patients with chronic patella dislocations and occurred an average of 13.8 months postoperatively. Overall, autograft was costlier than allograft because of the cost of reoperation. Conclusion: This study supports the use of allograft for chronic patellar instability because of improved graft survivorship and clinical outcome scores, as well as the lower cost and reoperation rate.

Pediatric Complex Metacarpophalangeal Joint Dislocation of the Index Finger.

BACKGROUND: Metacarpophalangeal (MCP) joint dislocations are the result of a hyperextension injury. Complex MCP joint dislocations-those that are irreducible to closed maneuvers and require surgical intervention-are considered uncommon, even in the pediatric population. Although several structures have been identified that contribute to irreducible dislocations, the volar plate is the most significant barrier to reduction through interposition into the MCP joint. Key differences that require consideration for MCP joint dislocations in pediatric patients include ligamentous laxity, the absence of sesamoid bones, the possibility for cartilage fractures, and the possibility of growth arrest. Open surgical intervention for a complex MCP joint dislocation is performed through either the volar or dorsal approach. Controversy exists about which approach is superior. CASE REPORT: We present the case of a 7-year-old female who sustained a complex MCP joint dislocation of the index finger. After numerous unsuccessful attempts at closed reduction, the patient underwent open reduction through the dorsal approach. The phalangeal head had buttonholed through the volar plate and was reduced by using a Freer elevator as a lever and applying gentle traction and flexion. At 4-week follow-up, the patient was pain-free and had regained nearly full range of motion of the index finger MCP joint. CONCLUSION: In addition to the classic volar and dorsal approaches, different techniques have been used to reduce complex dislocations in pediatric patients, including arthroscopic surgery, a percutaneous technique with manipulation of a skin hook, and a percutaneous technique with a dorsal incision. As demonstrated in this case, open reduction through the dorsal approach remains a viable treatment option for complex MCP joint dislocations in the pediatric population.

Post-traumatic nonunion of the clavicle in a 4-year-old boy and the importance of vitamin D level testing.

Clavicle fractures in children are common and usually go on to achieve solid union with closed treatment. A limited number of pediatric clavicle fracture nonunion cases have been reported in the literature, none of which were directly associated with hypovitaminosis D. We report the youngest case to our knowledge in a 4-year-old vitamin D-deficient male with a 6-month-old right midshaft clavicle fracture nonunion that was treated successfully with vitamin D supplementation, followed by open reduction and internal fixation with autologus iliac crest bone grafting.

Early onset scoliosis: the value of serial risser casts.

BACKGROUND: Treatment of early onset scoliosis (EOS) is challenging. In many cases, bracing will not be effective and growing rod surgery may be inappropriate. Serial, Risser casts may be an effective intermediate method of treatment. METHODS: We studied 20 consecutive patients with EOS who received serial Risser casts under general anesthesia between 1999 and 2011. Analyses included diagnosis, sex, age at initial cast application, major curve severity, initial curve correction, curve magnitude at the time of treatment change or latest follow-up for those still in casts, number of casts per patient, the type of subsequent treatment, and any complications. RESULTS: There were 8 patients with idiopathic scoliosis, 6 patients with neuromuscular scoliosis, 5 patients with syndromic scoliosis, and 1 patient with skeletal dysplasia. Fifteen patients were female and 5 were male. The mean age at first cast was 3.8±2.3 years (range, 1 to 8 y), and the mean major curve magnitude was 74±18 degrees (range, 40 to 118 degrees). After initial cast application, the major curve measured 46±14 degrees (range, 25 to 79 degrees). At treatment change or latest follow-up for those still in casts, the major curve measured 53±24 degrees (range, 13 to 112 degrees). The mean time in casts was 16.9±9.1 months (range, 4 to 35 mo). The mean number of casts per patient was 4.7±2.2 casts (range, 1 to 9 casts). At the time of this study, 7 patients had undergone growing rod surgery, 6 patients were still undergoing casting, 5 returned to bracing, and 2 have been lost to follow-up. Four patients had minor complications: 2 patients each with superficial skin irritation and cast intolerance. CONCLUSIONS: Serial Risser casting is a safe and effective intermediate treatment for EOS. It can stabilize relatively large curves in young children and allows the child to reach a more suitable age for other forms of treatment, such as growing rods. LEVEL OF EVIDENCE: Level IV; case series.

Are disulfiram-like reactions associated with abacavir-containing antiretroviral regimens in clinical practice?

Abacavir is metabolized primarily by two enzymes: alcohol dehydrogenase and gluconyl transferase. Under normal conditions, alcohol is hepatically cleared via alcohol dehydrogenase to acetaldehyde, and subsequently by acetaldehyde dehydrogenase (ACD) to acetic acid. Disulfiram acts as an ACD blocker. Abacavir may also act as an inhibitor of alcohol dehydrogenase, which raises the possibility of disulfiram-like reactions (if complete inhibition occurs) or reduced alcohol tolerance (if partial inhibition occurs) occurring with abacavir therapy.

PDGF alpha-receptor signal strength controls an RTK rheostat that integrates phosphoinositol 3'-kinase and phospholipase Cgamma pathways during oligodendrocyte maturation.

Receptors with tyrosine kinase activity (RTKs) control tissue growth and development in metazoans. How they generate cell-specific responses remains essentially unknown; one model proposes that distinct RTKs activate different second-messenger pathways, whereas a second proposes that all RTKs deliver a generic "go" signal to these pathways that is uniquely interpreted by downstream, cell-specific response competence factors. We examine pathway activation and pathway-specific responses downstream of PDGFalpha receptors, whose expression in the developing CNS identifies oligodendrocyte progenitor cells (OPCs) and whose activation controls OPC proliferation, migration, survival, and maturation. PDGFRalpha-null mice die in utero, and OPCs that emerge before their demise have migration and proliferation defects and rapidly differentiate into postmitotic oligodendrocytes in vitro. OPCs from hemizygous mice also undergo precocious differentiation, indicating a role for PDGFRalpha gene dosage in timing OPC maturation. The rescue of PDGFRalpha-null OPCs with PDGFRalpha transgenes revealed specific roles for the phosphatidylinositol 3-kinase (PI3K) and phospholipase Cgamma (PLCgamma) pathways and a distinct ligand concentration dependence. Activation of the PI3K pathway is required for PDGFRalpha-induced migration, whereas activation of both PI3K and PLCgamma are required for PDGFRalpha-induced proliferation. For proliferation, PI3K activation is required at low ligand concentration, whereas PLCgamma is required at high signal strength. Dose-response studies further demonstrate that PDGFRalpha activates PI3K at low ligand concentrations, whereas PLCgamma is activated at high signal strength. Thus, PDGFRalpha signaling acts like a rheostat rather than generic ON switch, with signal strength dictating pathway activation during OPC maturation.