Patient-specific biodegradable implant in pediatric craniofacial surgery

Surgical correction of premature fusion of calvarial sutures involving the fronto-orbital region can be challenging due to the demanding three-dimensional (3D) anatomy. If fronto-orbital advancement (FOA) is necessary, surgery is typically performed using resorbable plates and screws that are bent manually intraoperatively. A new approach using individually manufactured resorbable implants (KLS Martin Group, Tuttlingen, Germany) is presented in the current paper. Preoperative CT scan data were processed in iPlan (ver. 3.0.5; Brainlab, Feldkirchen, Germany) to generate a 3D reconstruction. Virtual osteotomies and simulation of the ideal outer contour with reassembled bony segments were performed. Digital planning was transferred with a cutting guide, and an individually manufactured resorbable implant was used for rigid fixation. A resorbable patient-specific implant (Resorb X-PSI) allows precise surgery for FOA in craniosynostosis using a complete digital workflow and should be considered superior to manually bent resorbable plates.

Greenstick fractures of the middle third of the forearm. A prospective multi-centre study

BACKGROUND

Greenstick fractures suffered during growth have a high risk for refracture and posttraumatic deformity, particularly at the forearm diaphysis. The use of a preemptive completion of the fracture by manipulation of the concave cortex is controversial and data supporting this approach are few.

AIM

Aim of this study was to determine the factors which predispose to refracture and deformities, and to define therapeutic strategies.

METHODS

We prospectively gathered clinical and radiographic data over a period of one year on greenstick fractures of the middle third of the forearm in children as part of a multi-centre study. Endpoint was a follow-up visit at one year. Radiographic deformity, state of consolidation at resumption of physical activities and refracture rate were analysed statistically (ANOVA, Student's t-test and Pearson's chi-square test) with regard to patient age, gender, fracture type, therapy and time in plaster.

RESULTS

We collected the data of 103 patients (63 boys, 40 girls), average age 6.6 years (1.3-14.5 years), the vast majority of whom had a combined greenstick fracture of the radius and ulna. 6.7% of the patients sustained a refracture within 49 days (29-76) after plaster removal. They were significantly older (p=0.017) with a significantly higher incidence of manual completion of the fracture with radiographic signs of partial consolidation (p=0.025). Residual deformities were significantly smaller after completion of the fracture compared to reduction without completion (p=0.019) or plaster fixation alone (p<0.005).

CONCLUSIONS

Completion of a greenstick fracture does not prevent refracture. Nevertheless, it diminishes the extent of secondary deformities in cases where the primary angulation exceeds the remodelling capacity. Prevention of refracture should include a routine radiographic follow-up 4-6 weeks after injury with continuation of plaster fixation in cases of partial consolidation.

Conservative management of significant epidural haematomas in children

OBJECTIVE

A significant epidural haematoma (EDH) is generally treated by craniotomy and evacuation. This is a report of conservative management following an EDH on computerized tomography (CT) in a paediatric population. The authors examined whether conservative treatment of radiologically significant EDH is a successful and safe therapeutic option.

METHODS

Retrospective data were collected from charts of patients with conservatively treated EDH in the Department of Surgery of the University Children's Hospital Zurich between September 1993 and January 2004. Included were patients without focal neurological deficits, with a Glasgow Coma Scale (GCS) of 15 and an initial CT demonstrating an EDH with a minimal thickness of 1 cm. Mild clinical symptoms of raised intracranial pressure such as headache, nausea or vomiting were treated symptomatically. Follow-up included a standardized interview, a neuropaediatric examination and CT.

RESULTS

Thirteen children with EDH had successful conservative management. Only one 12-year-old female patient with a delayed diagnosed frontal EDH required surgical intervention 24 h after admission and 5 days after the accident. Clinical follow-up showed patients without neurological deficits, a Glasgow Outcome Scale of 5 and no post-traumatic sequelae over an average of 4 4/12 years (range 4 months to 10 4/12 years). Follow-up CT showed complete resolution of the EDH within 2 to 3 months.

CONCLUSIONS

Our results demonstrate that significant EDH can be treated non-operatively in neurologically normal children. We recommend that such treatment be performed in specialised paediatric centres under adequate neurological observation since prompt emergency operation in case of neurological deterioration should be provided.

Medial clavicular epiphysiolysis in children: the so-called sterno-clavicular dislocation

We retrospectively reviewed six pediatric cases of medial clavicular injury, i.e., epiphyseal separation (Salter/Harris type I or II injury), diagnosed between 1993 and 1997. The clavicular metaphysis was displaced posteriorly in three cases and anteriorly in three. On conventional radiographic views the diagnosis was initially missed in two of three retrosternal dislocations. A special X-ray projection (described by Heinig) or computed tomography (CT) permitted correct diagnosis. Anterior dislocations were immediately and correctly diagnosed. Closed reduction successfully treated retrosternal displacement in two of the three patients. The third patient needed open reduction and internal fixation. Open reduction and internal fixation had to be performed in all three patients with anterior displacement. Follow-up assessment showed perfect functional results in all cases. Direct visualization during open reduction, which was necessary in four of six cases, yielded clear evidence that the so-called sternoclavicular dislocation in children and young adults is, in fact, a fracture of the medial growth plate with posterior or anterior displacement of the metaphysis.

Outcome in children with space-occupying posterior fossa arachnoid cysts

While prognostic information for Dandy-Walker syndrome and non-progressive cerebellar ataxia/cerebellar hypoplasia is available, surprisingly scant literature reports are found for space-occupying posterior fossa arachnoid cysts (PFAC). We describe the outcome of patients with symptomatic PFAC shunted as infants. Only 11 children were seen over a 20-year period (1980-1999). Cyst location was retrocerebellar (n = 8), supravermian (n = 2) and in the cerebellopontine angle (n = 1). Motor and cognitive impairments in one child were interpreted as the result of neurosurgical complications (intraventricular and intracerebral haemorrhage). One 6-year-old boy had mild truncal ataxia and mild cognitive delay. The 9 other patients had no evidence of ataxia or clumsiness and had average, some even above average, cognitive ability and scholastic achievements. Epilepsy was not a feature. We conclude that the prognosis of PFAC for cognitive development and neurological signs is favourable.

Fractures of the neck of the radius in children

The treatment of fractures of the neck of the radius in children is difficult, particularly if the angulation of the fracture exceeds 60°. Since 1994 we have used closed reduction and stabilisation with an intramedullary Kirschner wire in patients with grade-IV fractures according to the classification of Judet et al. In a retrospective analysis of a two-year period (1994 to 1996), 324 children with fractures of the elbow were treated in our department. Of these, 29 (9%) had a fracture of the neck of the radius; six were grade-IV injuries (1.9%). Five of the latter had an excellent postoperative result with normal movement of the elbow and forearm. One patient with a poor result had a concomitant dislocation of the elbow.

Our results suggest that closed reduction and intramedullary pinning of grade-IV fractures allows adequate stabilisation while healing occurs.

Fractures of the neck of the radius in children. Early experience with intramedullary pinning

The treatment of fractures of the neck of the radius in children is difficult, particularly if the angulation of the fracture exceeds 60 degrees. Since 1994 we have used closed reduction and stabilisation with an intramedullary Kirschner wire in patients with grade-IV fractures according to the classification of Judet et al. In a retrospective analysis of a two-year period (1994 to 1996), 324 children with fractures of the elbow were treated in our department. Of these, 29 (9%) had a fracture of the neck of the radius; six were grade-IV injuries (1.9%). Five of the latter had an excellent postoperative result with normal movement of the elbow and forearm. One patient with a poor result had a concomitant dislocation of the elbow. Our results suggest that closed reduction and intramedullary pinning of grade-IV fractures allows adequate stabilisation while healing occurs.

[Rational utilization of antibiotics in critically ill children]

BACKGROUND

The high risks associated with untreated infection in critically ill newborns or children lower the threshold for prescription of antibiotic treatment. Inappropriate use of antibiotic therapy promotes the emergence of resistant strains. This study had three aims: to identify sources of inappropriate antibiotic utilisation, to develop revised guidelines and to implement changes.

METHODS

An observational study was performed in a tertiary, multidisciplinary, neonatal and paediatric intensive care unit (PICU) of a university teaching hospital during a 7-month period (456 admissions). Guidelines addressing one of the identified sources of inappropriate utilisation (prophylaxis following surgery) were developed according to published evidence and implemented, and the effect on prescription patterns was assessed during a second observation period.

RESULTS

Patients received systemic antibiotics during 54.6% of all hospitalisation days. Antibiotics prescribed for suspected or proven infection were often continued 1-2 days beyond the intended duration. Prophylaxis accounted for 28% of all systemic antibiotics given, and postsurgical prophylaxis accounted for 14.6% of all exposure days. The literature search revealed little evidence to support this practice. After new guidelines were introduced with the aim of restricting surgical prophylaxis to a single dose prior to surgery, the rate of postsurgical prophylaxis dropped from 14.6 to 11.2% of all exposure days, accompanied by a significant decline in the overall exposure rate from 54.6 to 50.2% of all hospitalisation days.

CONCLUSION

Several sources of inappropriate antibiotic utilisation were identified. These include failure to discontinue treatment and prolonged prophylaxis after surgery. Implementation of new guidelines reduced antibiotic utilisation.

[Ankle joint injuries in children. Chief presentation of the 83rd Annual Meeting of the Swiss Society of Traumatology and Insurance Medicine, 4-5 September 1997, Winterthur]

Children are not just small adults. Depending on age and skeletal maturity, they demonstrate typical lesions. All major ankle ligaments, except the interosseous ligament, either insert or originate from the tibial and fibular epiphysis. In young children, the physeal structures are more likely to break than the ligaments. After a sprain of the ankle, we observe avulsion fractures of the ligaments or physeal fractures as described by Salter and Harris. In adolescents ligamentous ruptures can occur and, because of the asymmetric physeal closure, two- and threeplane fractures (transitional fractures) appear.

Efficacy of cultured epithelial autografts in pediatric burns and reconstructive surgery

BACKGROUND

Cultured epithelial autografts are regularly used in burn patients, but they have not been tested in patients undergoing reconstructive surgery. The aim of this study was to analyze and compare the efficacy of cultured grafts in both burn and reconstructive surgery patients.

METHODS

In six children with severe and massive burns, full-thickness areas were grafted with cultured grafts. In another six children with hypertrophic or hyperpigmented scars, or both, cultured grafts were used to cover defects resulting from scar excision or deep dermabrasion.

RESULTS

In burn surgery the final cover rate averaged 60% (range, 0% to 100%). The functional and cosmetic results were good and at least equivalent to results after conventional grafting. Fragility, infection, and, in particular, mechanical instability of cultured grafts during the first weeks after transplantation were the main problems encountered. In reconstructive surgery the final cover rate was 100% in all patients. The functional and cosmetic results were very good and considered better than those obtained by using conventional grafting techniques. No major management problems were encountered.

CONCLUSIONS

In massively burned children, cultured epithelial autografts represent an effective additional and potentially lifesaving method to conventional grafting. Questions remain regarding the use of this technique to treat less severe burns. For resurfacing-type scar revisions, cultured epithelial autografts yield excellent results that appear to be superior to those of conventional techniques.

Cross-linking of the dermo-epidermal junction of skin regenerating from keratinocyte autografts. Anchoring fibrils are a target for tissue transglutaminase

Since transglutaminases create covalent gamma-glutamyl-epsilon-lysine cross-links between extracellular matrix proteins they are prime candidates for stabilizing tissue during wound healing. Therefore, we studied the temporo-spatial expression of transglutaminase activity in skin regenerating from cultured epithelial autografts in severely burned children by the specific incorporation of monodansylcadaverine into cryostat sections from skin biopsies obtained between 5 d to 17 mo after grafting. The dansyl label was subsequently immunolocalized in the epidermis, dermal connective tissue, and along the basement membrane. Incubation of cryosections of normal and regenerating skin with purified tissue transglutaminase confirmed the dermo-epidermal junction and the papillary dermis as targets for this enzyme and revealed that in regenerating skin transamidation of the basement membrane zone was completed only 4-5 mo after grafting. Immunoelectron microscopy revealed that three distinct regions on the central portion of anchoring fibrils were positive for monodansylcadaverine in normal skin which were negative during the initial phase of de novo formation of anchoring fibrils in regenerating skin. Biochemically, we identified collagen VII as potential substrate for tissue transglutaminase. Thus, tissue transglutaminase appears to play an important role not only in cross-linking of the papillary dermis but also of the dermo-epidermal junction in particular.

Fibrillin and elastin expression in skin regenerating from cultured keratinocyte autografts: morphogenesis of microfibrils begins at the dermo-epidermal junction and precedes elastic fiber formation

The temporo-spatial expression of fibrillin and elastin in skin regenerating from autologous keratinocyte grafts was studied in three burned children. Skin biopsies taken between 5 days and 17 months after grafting were investigated by conventional immunofluorescence, confocal laser scanning, and electron microscopy. Fibrillin, the major component of 10-12nm microfibrils, appeared 5 days after grafting in a band-like fashion similar to collagen VII at the prospective basement membrane, and the formed the characteristic microfibrillar candelabra at the dermo-epidermal junction by fusion of several fine microfibrils to communicating microfibrils projecting downward into the reticular layer of the neodermis. Four to five months after grafting, several communicating microfibrils were connected to a web of horizontally undulating microfibrils of the neodermis which had developed independently. Elastin was first identified in the deeper neodermis 1 month after grafting as granular aggregates and 4 months after grafting on fibrillar structures and surrounding capillaries of the upper neodermis. Association of elastin with microfibrils in the papillary dermis was not detectable before month 17. Our findings suggest that the cutaneous microfibrillar apparatus develops simultaneously at both the dermo-epidermal junction and the reticular dermis and is a prerequisite for elastic fiber formation. In addition, it might be a driving force for the formation of the papilla-rete ridge pattern.

Operative treatment of solitary bone cysts with tricalcium phosphate ceramic. A 1 to 7 year follow-up

From 1984 to 1990 we treated 18 patients aged 5 to 15 1/2 years with solitary bone cysts of the humerus, the femur and the calcaneus. To fill the defect, tricalcium phosphate (TCP) instead of bone grafting was used. The clinical and radiological long-term results up to seven years postoperatively are reported. In 16 patients TCP was well incorporated without any adverse reaction to the synthetic material. Two patients with a recurrence of the bone cyst were successfully reoperated. We conclude that ceramics are a cheap and easy available substitute for bone grafts in the treatment of solitary bone cysts.