Effect of asymmetrical configuration of pins in the TSF external fixator used for tibial lengthening in a pediatric population.

BACKGROUND: The Taylor Spatial Frame (TSF) is a relatively new circular external fixator linked with a computer program used in limb reconstruction surgery. It is routinely used in our unit (Royal Manchester Children's Hospital) for pediatric tibial lengthening. METHODS: The case notes and radiographs of 17 children who underwent 18 tibial lengthenings were reviewed. The TSF was attached to the tibia using a hybrid fixation method in the safe zone with two 1.8 mm tensioned smooth wires and 2 anteriorly placed hydroxyapatite-coated pins. Mechanical compression testing of our TSF construct was performed and compared with a double-ring Ilizarov frame construct fixed with only tensioned wires. RESULTS: Out of the 18 tibiae lengthened 14 (77.8%) had a significant anterior angulation (>10 degrees) at the end of the distraction period that was corrected with a residual TSF program, with no known long-term consequences. The mechanical tests showed that the Ilizarov frame showed a more symmetrical distribution of loading in compression when compared with the TSF. With increasing load the TSF had the tendency to angulate anteriorly, that is, the apex of the angulation was pointing toward the 2 pins. CONCLUSIONS: The problem of anterior angulation observed in our clinical and mechanical studies is due to instability of the fixation of the proximal part of the frame. Surgical techniques that can improve the stability of the proximal fixation and promote symmetrical loading are discussed.

Congenital bowing of the tibia due to infantile lipofibromatosis corrected with a Taylor Spatial Frame.

Congenital lipofibromatosis is a rare slow growing benign fibrofatty neoplasm presenting in childhood. The case of a boy presenting soon after birth with diffuse lower extremity enlargement associated with a significant tibial deformity is presented. Magnetic resonance imaging and soft tissue biopsy confirmed the diagnosis of lipofibromatosis. The child started having problems with his gait after the age of two. The tibial bowing was corrected gradually using a Taylor Spatial Frame resulting in a good clinical outcome.

Neuroblastoma: a rare cause of a limping child. How to avoid a delayed diagnosis?

UNLABELLED: Neuroblastoma is the most common solid extracranial tumor of childhood. Even though >25% of presentations are orthopaedic in nature, ranging from a limp to lower limb paralysis, neuroblastoma is a rare cause of limping in childhood and can therefore be easily missed by the admitting orthopaedic surgeon. Four cases of metastatic neuroblastoma are reported who all presented with hip pain within the last 3 years at Royal Manchester Children's Hospital. They all posed a diagnostic dilemma and an alternative diagnosis was initially made. A simple screening examination of the abdomen after ultrasonographic hip examination for sepsis would have led to an earlier diagnosis in all 4 cases. We suggest that including the abdomen in children undergoing a hip sonographic examination in those who are slightly atypical in nature or have indications of malignancy may lead to an early diagnosis of this rare cause of hip pain. LEVEL OF EVIDENCE: IV.

Hypertension as a complication of circular external fixators.

Hypertension is not a recognized complication of circular external fixation. The aim of this study was to determine the incidence of hypertension following this procedure. A retrospective review of 57 patients was carried out between January 2006 and May 2010. At least three blood pressure readings were used to define hypertension. Five of the 41 qualifying patients (12.2%) developed hypertension. Three of these were found to have a sustained hypertension throughout the frame period, two requiring treatment for visual symptoms and left ventricular hypertrophy. A limb reconstruction surgeon needs to be alert to this potential complication to initiate prompt investigations and treatment.

The use of the taylor spatial frame for the treatment of unstable tibial fractures in children.

OBJECTIVES: The aim of this study was to assess the use of the Taylor Spatial Frame (TSF) in the treatment of unstable tibial fractures in skeletally immature patients. DESIGN: Retrospective review. PATIENTS/PARTICIPANTS: Twelve consecutive skeletally immature patients with unstable tibial fracture treated at our centre with a TSF. INTERVENTION: A TSF was applied by a single surgeon for the stabilization of unstable tibial fractures. MAIN OUTCOME MEASURES: Time to union, nonunion, malunion, reoperations, leg length discrepancy, and complications such as infections and compartment syndrome in both closed and open tibial fractures. RESULTS: Over a 4-year period, 8 patients with closed unstable tibial fractures and 4 patients with grade IIIB open fractures were treated with a TSF by a single surgeon. Union was achieved in all cases with no residual angulation and no leg length discrepancy. The mean time of the TSF treatment for the 8 closed fractures was 12.6 (range: 8-22) and for the 4 grade IIIB open fractures was 24.25 weeks (range: 13-36). There was 1 patient who developed compartment syndrome after application of the TSF and 2 who developed superficial pin site infections treated with oral antibiotics. CONCLUSIONS: This study supports the use of TSF in experienced users for the treatment of unstable closed and open fractures in skeletally immature patients.

An aneurysmal bone cyst within the proximal fibula causing common peroneal nerve palsy.

The case of a 15-year-old patient presenting with pain as well as paraesthesia over the lateral aspect of the leg is reported. Clinical and radiological investigations showed an aneurysmal bone cyst arising from the proximal fibula and pressing on the common peroneal nerve. Surgical decompression of the nerve and curettage of the cyst was performed resulting in complete resolution of his symptoms. Our aim is to alert surgeons that this problem may occur and that the entire nerve needs to be exposed when dealing with the cyst.

Clinical and radiological outcome of combined femoral and Chiari osteotomies for subluxed or dislocated hips secondary to neuromuscular conditions: a minimum of 10-year follow-up.

We evaluated the medium-term results of combined Chiari pelvic and femoral osteotomies performed at the Manchester Children's Hospitals between the years 1985 and 1994. The indications for these osteotomies were either hip dislocation or subluxation in children with neuromuscular disease. We clinically and radiologically evaluated 20 hips in 18 patients treated for hip subluxation and dislocation with Chiari osteotomy. The average post-operative clinical follow-up period was 11.32 years (range 10.1-12.9). The mean age at the time of surgery was 7.3 years (range 3.1-13.2 years). Clinically, 9 hips had a 'Good' outcome, 10 were "Fair" and 1 was "Poor" according to Osterkamp criteria. At last follow-up, radiologically the mean Sharp's angle improved from 51° to 44° (p = 0.09), the mean Centre-Edge angle improved from -16° to 18° (p = 0.067), the mean Migration Index improved from 59 to 29 % (p = 0.011), the mean femoral neck-shaft angle from 160° to 117° (p < 0.0001) and the Severin criteria improved from an average grade of 4.5-2.9 (p < 0.0001). Our results compared to previous studies confirm that combined femoral and Chiari osteotomies provide a favourable outcome both clinically and radiologically at least 10 years following surgery. Accepting that the numbers are small, we report no statistical difference in the mean age at the time of operation when comparing the children with an eventual 'good' outcome and those with an eventual 'fair' or 'poor' outcome.

Single screw fixation in stable and unstable slipped upper femoral epiphysis.

The aim of this single centre retrospective study was to assess the outcome of patients after the fixation of slipped upper femoral epiphysis (SUFE) using a single cannulated screw. Thirty-eight slips, 28 stable and 10 unstable were treated with single in-situ screw fixation. The minimum follow-up was 1 year. The overall adverse outcome in terms of avascular necrosis (AVN), chondrolysis and revision surgery for slip progression was 18%, which was considered satisfactory. Slip progression of more than 10° was higher in the unstable when compared with the stable group but not statistically significant. Two out of the nine satisfactorily fixed unstable slips required revision surgery as opposed to none in the stable group. The incidence of AVN in the unstable group was 20%. There were no cases of AVN in the stable group. The adverse outcome in terms of AVN, chondrolysis and revision surgery for slip progression was significantly higher in the unstable group. In our study, results of single screw fixation for SUFE were found to be satisfactory as shown by earlier studies with the unstable SUFEs as expected having a poorer outcome when compared with the stable SUFEs.

Osteochondrosis of the proximal phalanx of the hallux in adolescent footballers.

We report two cases with radiographic appearances of osteochondrosis in the proximal phalanx of the big toe in adolescent footballers. The radiological findings were those of initial fragmentation with subsequent healing of the epiphysis. This is the first report of osteochondrosis at this site. Local pain was accompanied by swelling with restriction of dorsiflexion of the metatarsophalangeal joint of the big toe. The condition was self-healing over a 2-4-year period. It needs to be included in the differential diagnosis of painful hallux in adolescent footballers.

Comparison of bacteriologically proven septic arthritis of the hip and knee in children, a preliminary study.

The hip and knee are the commonest joints affected by septic arthritis in the pediatric age group. Both can present as a limping, unwell child and can be difficult to diagnose. The primary aim of this study is to review and compare characteristics of pediatric patients with culture positive septic arthritis of the hip to those with culture positive septic arthritis of the knee. We retrospectively reviewed all patients who were clinically diagnosed with acute septic arthritis of either hip or knee in a tertiary pediatric hospital for a period of 3 years. Twelve of 29 patients who underwent arthrotomy for presumed septic arthritis of the hip and 7 of 37 patients who underwent arthrotomy for presumed septic arthritis of the knee had positive joint cultures. Patients with septic arthritis of the knee were much younger than that with septic arthritis of the hip. Patients with presumed septic arthritis of the knee based on clinical picture were less likely to have a positive synovial fluid culture. Children with septic arthritis of the knee did not follow Kocher criteria in the same way that children with septic arthritis of the hip did.

Pelvic osteomyelitis in children.

Pelvic osteomyelitis is a rare disease that presents like many other common paediatric orthopaedic conditions. The diagnosis and management of the disease is often delayed and as a consequence this may contribute to increased morbidity in affected individuals. In an attempt to improve our diagnostic accuracy, 23 cases of pelvic osteomyelitis presenting to our tertiary referral centre between 1998 and 2006 were reviewed. Case notes were reviewed to examine clinical, pathological and radiological variables attributable to pelvic osteomyelitis, as well as subsequent management of the disease. Pelvic osteomyelitis was diagnosed on the basis of a positive bone and/or magnetic resonance scan. The presentation was associated with a limp and a history of non-weight bearing. The patients presented with an average temperature of 38.4 degrees C and pathology revealed an average erythrocyte sedimentation rate and C-reactive protein of 61.2 and 59.1, respectively. A child with a clinical picture including limping, fevers and raised inflammatory markers should be approached with a high index of suspicion of pelvic osteomyelitis. Seven patients in our series required surgical intervention for debridement and washout. Magnetic resonance imaging performed in the most recent cases was found to be a useful investigation in the diagnosis and management of pelvic osteomyelitis.

Hypertension as a complication of Taylor spatial frame.

Circular external fixators in children are widely used for limb lengthening, deformity correction and the treatment of fractures. We report a case of successful management of hypertension in a 13-year-old treated with a Taylor spatial frame after a road traffic accident and a tibial fracture. A heightened awareness of the association of hypertension and external fixators is required to improve patient outcomes. Outcomes are improved by prompt diagnosis and treatment of hypertension, preventing hypertensive end-organ damage, choice of an appropriate first line antihypertensive treatment, and not subjecting children to invasive investigations looking for an alternative secondary cause of hypertension.

Bisphosphonate-laden acrylic bone cement: mechanical properties, elution performance, and in vivo activity.

Cemented total hip replacements generally fail after 10-20 years, often due to implant loosening from bone resorption. Bisphosphonates such as zoledronic acid (ZA) and pamidronate (PAM) are potent inhibitors of bone resorption. The local delivery of bisphosphonates via acrylic bone cement could decrease osteolysis and prolong implant lifespan. Conflicting studies suggest that bisphosphonate loading may or may not reduce the mechanical properties of acrylic bone cement. We assayed acrylic bone cement laden with ZA or PAM at different concentrations and diluent volumes. Four-point bend testing and compressive testing indicated that high volumes of diluent (with or without bisphosphonate) significantly reduced bending modulus and compressive strength. Radiography and electron microscopy indicated that high diluent volumes generated abnormal acrylic bone cement structure. After 6 weeks of incubation in saline, only 0.9% w/w of the total bisphosphonate incorporated in acrylic bone cement eluted in vitro, indicating a slow elution rate. In vivo testing was performed using a rat model. Cement cylinders were inserted into incisions in rat distal femora and ZA delivered locally (via elution from acrylic bone cement) or systemically (via injection). At 4 weeks postoperatively, dual energy X-ray absorptiometry demonstrated no significant increase in local bone mineral density (BMD) adjacent to ZA-laden implants. In contrast, systemic ZA delivery (0.1 mg/kg) led to a large (48.6%) and significant increase in BMD. Thus, systemic delivery appears more effective than local delivery.

Posterior sloping angle of the capital femoral physis: interobserver and intraobserver reliability testing and predictor of bilaterality.

The management of the contralateral hip after unilateral slipped capital femoral epiphysis (SCFE) is controversial. The aims of this study were to assess the interobserver and intraobserver reliability of the posterior sloping angle (PSA) as described by Barrios et al (J Pediatr Orthop. 2005;25:445-449) and whether it can be used as a predictor of need for prophylactic pinning of the contralateral hip. The PSA was measured by 4 different surgeons on 2 separated occasions in 47 unaffected contralateral hips after unilateral SCFE. The interobserver intraclass correlation coefficient (ICC) was 0.83 (excellent) for the first set of measurements and 0.74 (fair to good) for the second set of measurements. Measurement of the intraobserver ICC revealed an excellent agreement (ICC > 0.75) in 3 of the 4 surgeons and fair to good agreement in 1 of the surgeons (ICC between 0.4 and 0.74). Comparison of the PSA measurements of the first author (M.Z.) with a control group of 20 hips revealed that the PSA was significantly higher (P < 0.05) in the group of patients that eventually had a contralateral slip when compared with the PSA of patients in the study group who did not slip and with normal hips in the control group. Patients with contralateral SCFE that did not slip had a significantly higher PSA (P < 0.05) when compared with normal individuals. A PSA of 14.5 degrees or more is recommended for prophylactic pinning of the contralateral hip. The number needed to treat (NNT) at this cut off to avoid 1 future slip was calculated to be 1.9.

Intraoperative stability testing of lateral-entry pin fixation of pediatric supracondylar humeral fractures.

The aims of this study were (1) to ascertain prospectively whether rotational instability can be determined intraoperatively and (2) to quantify the incidence of rotational instability after lateral-entry wire fixation in type-3 supracondylar humeral fractures in children according to Wilkins modification of Gartland classification. (Fractures in Children. Vol 3. 4th ed. 1996:669-750). Twenty-one consecutive patients admitted with type-3 supracondylar fractures at the Children's Hospital at Westmead were surgically treated according to a predetermined protocol. After closed fracture reduction, 2 lateral-entry wires were inserted under radiographic control. Stability was then assessed by comparing lateral fluoroscopic images in internal and external rotation. If the fracture remained rotationally unstable, a third lateral-entry wire was inserted, and images were repeated. A medial wire was used only if instability was demonstrated after the insertion of 3 lateral wires. Rotational stability was achieved with 2 lateral-entry wires in 6 cases, 3 lateral-entry wires in 10 cases, and with an additional medial wire in 5 cases. Our results were compared with a control group of patients treated at our hospital before the introduction of this protocol. No patients required a reoperation after the introduction of our protocol as opposed to 6 patients in the control group. On analysis of radiographs, the protocol resulted in significantly less fracture position loss as evidenced by change in Baumann angle (P < 0.05) and lateral rotational percentage (P < 0.05). We conclude that supracondylar fractures that are rotationally stable intraoperatively after wire fixation are unlikely to displace postoperatively. Only a small proportion (26%) of these fractures were rotationally stable with 2 lateral-entry wires.

Unilateral limb deformity due to fibrous tethers: a report of three cases.

Fibrous tethers are a rare cause of unilateral limb deformity. A review of the literature revealed 9 cases previously described, all located in the distal femur. We report 3 additional cases of fibrous tethers, 2 of which were located in anatomical areas not previously described. The fibrous tethers were excised in all cases, and an osteotomy was performed in 2 of the cases. The clinical, radiological, and histopathologic findings are discussed for each case.

Soft tissue Ilizarov correction of congenital talipes equinovarus--5 to 10 years postsurgery.

The aim of this study was to address concerns regarding maintenance of correction of foot deformity after soft tissue Ilizarov distraction in relapsed clubfeet. We retrospectively reviewed the results of Ilizarov surgery of 19 rigid clubfeet in 14 children. The postoperative follow-up was at least 5 years (range, 5-10 years). All patients were assessed using the International Clubfoot Study Group score. This is a comprehensive scoring system published in 2003, incorporating morphological, functional, and radiological assessments. Patient and parent satisfaction was also assessed. Using the International Clubfoot Study Group score, 14 of the 19 feet managed by the Ilizarov soft tissue distraction technique were graded good or excellent. Only 1 patient experienced recurrence of the deformity. Subjectively, 13 of the 14 children in the study were satisfied with the result of the treatment. The study confirms that the short-term good results reported previously are maintained at least 5 years after the operation. There are no other similar studies with a minimum 5-year follow-up.