Type II distal clavicle fractures: a retrospective review of surgical treatment

We retrospectively reviewed cases of 19 of 35 patients who underwent operative treatment for type II fractures of the distal clavicle over 7 years. The average age was 21.5 years. There were 15 males. Ten of the fractures occurred in vehicular accidents and eight in sports. Ten of the fractures were comminuted. All fractures were closed. Thirteen patients were treated with transacromial Kirschner wires and six by other methods. There were 10 satisfactory and nine unsatisfactory results. All six nonunions and five of the six deep infections occurred in those treated with transacromial wires. Our results indicate that transacromial wire fixation may not be the treatment of choice for this uncommon fracture.

A new model of implant-related osteomyelitis in rats

Infection related to osteosynthesis often has dramatic consequences for the patient. Prolonged hospitalization with systemic antibiotic therapy, several revision procedures, possible amputation, and even death may occur. To investigate the pathology of infection in orthopedic surgery, a new rat model of implant related osteomyelitis was developed. Three different concentrations (10(6), 10(3), and 10(2) colony-forming units (CFU)/10 microl) of Staphylococcus aureus were inoculated into the tibial medullary cavity with simultaneous insertion of a titanium Kirschner wire. Controls received phosphate-buffered saline (PBS). Each group consisted of 10 animals. Animals were followed for 4 weeks until sacrifice. X-rays of the tibiae were taken weekly, blood counts were analyzed, and body temperature and weight were determined. After sacrifice, infection was evaluated by histological and microbiological investigations. All animals inoculated with Staph. aureus in either concentration developed microbiological, histological, and radiological signs of osteomyelitis in correlation to the amount of inoculated bacteria. X-rays clearly revealed osseous destruction after 14 days with progression of osteomyelitis during the following weeks. CFU/g bone and bone weight after sacrifice showed dependence on the amount of inoculated CFU. The histological results confirmed the radiological findings. No significant changes in blood counts, body weight, and body temperature between the groups could be observed. The results demonstrate that it is possible to develop a model of implant-related osteomyelitis in rats with dependence on the amount of inoculated bacteria. No other promoters of infection besides intramedullary insertion of titanium Kirschner wires were used in this model.

Complications of use of the Ilizarov technique in the correction of limb deformities in children

We reviewed the records of the first forty patients who had been managed at our institution with the Ilizarov technique for the correction of limb deformities, including limb-length inequality, to delineate the complications of this method of treatment. The duration of follow-up ranged from two and one-half to four years. A complication was defined as any untoward occurrence to a patient either during the course of treatment or after removal of the fixator. A major complication was considered one that necessitated an additional operative procedure; caused lasting sequelae, such as malunion, deformation of new bone, joint contracture or stiffness, or nerve palsy; or prolonged the treatment. A minor complication was regarded as one that responded to non-operative treatment and did not cause lasting sequelae, such as transient decreased motion of the joint, paresthesia, or pin-track infection. There were eighty-eight complications--thirty-eight, major, and the remaining fifty, minor--in the sixty-one segments of the limb that were treated; this represented an average of almost one and one-half complications for each segment. Twenty-nine unplanned operative procedures were performed either during treatment with the Ilizarov technique or after removal of the fixator. As anticipated, the prevalence of major complications was highest in the patients who had had more complex and prolonged treatment. Such complications were encountered less often as the surgeons gained experience with the procedure, but the rate of minor complications remained relatively constant, despite the increased experience.(ABSTRACT TRUNCATED AT 250 WORDS)

Salvage first MTP arthrodesis utilizing ICBG: clinical evaluation and outcome

Twelve patients (12 feet) underwent salvage first metatarsalphalangeal (MTP) arthrodesis with structural, interposition autologous iliac crest bone graft (ICBG). Eight patients had a bony defect secondary to failed first MTP joint implant arthroplasties, two had avascular necrosis (AVN) after failed bunion surgery, one had a nonunion of an attempted arthrodesis for failed bunion surgery, and one had been treated for osteomyelitis after cheilectomy. Eleven of the cases had a single dorsal plate secured by screws and one case had two plates, one dorsal and one medial. A plate, crossed screw(s) and/or K-wire combination were chosen in four cases. Indications included first MTP joint pain, metatarsalgia, intractable plantar keratoses (IPK), as well as a functionally and cosmetically short first ray refractory to non surgical management. Average preoperative shortening was 8.5 mm (range 5-17). Clinical arthrodesis was achieved after an average of 12 weeks (range 4-20). Radiographic arthrodesis was achieved in eleven of twelve feet at an average of 15 weeks (range 8-28), with one pseudoarthrosis. AOFAS forefoot clinical rating score averaged 70 points (max 90 after first MTP arthrodesis) at an average follow-up of 22 months (range 5-70). Sesamoiditis, prominent hardware and scar sensitivity were prevalent complaints in four patients postoperatively. Two cases required flap coverage for skin necrosis. Relief of metatarsalgia, good hallux alignment as well as improved patient satisfaction and function were achieved in all cases. There was no symptomatic progression of interphalangeal degenerative change postoperatively.

Transoral decompression, anterior plate fixation, and posterior wire fusion for irreducible atlantoaxial kyphosis in rheumatoid arthritis

STUDY DESIGN

Fifteen consecutive patients with irreducible atlantoaxial kyphosis caused by rheumatoid arthritis were treated by combined transoral odontoid resection, anterior plate fixation, and posterior wire fusion.

OBJECTIVES

To investigate the clinical results of this new surgical procedure.

SUMMARY AND BACKGROUND DATA

Irreducible atlantoaxial kyphosis in rheumatoid arthritis results from a destruction of the craniocervical joint ligaments and the anterior aspects of the lateral atlantoaxial joints. The development of a paradental synovial pannus and atlantoaxial joint impaction prevents reduction by conservative treatment, such as skull traction. Posterior surgical procedures for the treatment of the irreducible atlantoaxial kyphosis with spinal cord compression have been associated with high morbidity and mortality.

METHODS

Fifteen consecutive patients were treated by transoral odontoid resection. The fixation was performed with anterior plating, according to the method of Harms in combination with posterior wire fusion according to Brooks. Before and after surgery, evaluation was performed using the parameters of pain (visual analog scale), range of motion, and subjective assessment of improvement and the Health Assessment Questionnaire. The neurologic deficit was defined according to the classifications proposed by Ranawat, Frankel, and Nurwick. Plain radiographs, including lateral flexion and extension views, and magnetic resonance scans were obtained.

RESULTS

No perioperative fatality occurred. The average clinical and radiographic follow-up was 50.7 +/- 15.6 months (range, 26-77). Postoperative pain was relieved (mean pain score before surgery, 7.9 +/- 1.87; after surgery, 3.8 +/- 1.27), and the range of motion of all patients increased (mean 21.5 +/- 14.0 degrees for rotation; mean 17.2 +/- 5. 54 degrees for bending). The score on the Health Assessment Questionnaire increased in three patients, remained unchanged in three and decreased in six patients (three had died). All patients improved at least one Ranawat level after surgery, except a patient in Ranawat Class II, whose condition remained unchanged. All patients were satisfied with the procedure and reported subjective improvement.

CONCLUSION

Transoral plate fixation combined with posterior wire fixation after transoral odontoid resectionis an effective, reliable, and safe procedure for the treatment of irreducible atlantoaxial kyphosis in rheumatoid arthritis.

Neurosensory function of the inferior alveolar nerve after bilateral sagittal ramus osteotomy: a retrospective study of 68 patients

The aim of the present study was to report the incidence of neurosensory dysfunction in the lower lip and chin after bilateral sagittal split osteotomy at four postoperative time points, and the relation of impairment to factors connected with the operation. Sixty-eight patients who had undergone the procedure (at 136 operated sites) were reviewed, and neurosensory recovery was studied at 2, 6, 18 and finally 30 months postoperatively. A change in neurosensory recovery was seen over this period of time. Two months postoperatively, 84 sites had reduced sensitivity (62%). The incidence of disorder decreased to 52 sites (38%) at 6 months, 43 sites (32%) at 1.5 years and 32 sites (24%) at the final 2.5-year check up. The patient age at the time of surgery, the type of osteosynthesis and the perioperative position of the inferior alveolar nerve were variables that influenced the neurosensory outcome. In conclusion, this retrospective study shows that the most important factors influencing postoperative nerve function are patient age, fixation method and the perioperative position of the inferior alveolar nerve.

Treatment of comminuted intraarticular distal femur fractures with limited internal and external tensioned wire fixation

OBJECTIVE

Evaluate the treatment of C3 distal femur fractures with limited internal fixation and tensioned wire circular external fixation.

DESIGN

Prospective cohort study, from June 1992 to July 1996.

SETTING

Urban Level I trauma center.

PATIENTS

Sixteen fractures in sixteen patients: nine male, seven female. Fractures: C3.1 one, C3.2 one, C3.3 fourteen. Twelve fractures were open: one GI, seven GII, two GIIIA, one GIIIB, and one GIIIC.

INTERVENTION

Fractures were treated with limited open fixation of the condylar joint surface and tensioned wire circular external fixation of the metaphysis and shaft for axial alignment. Three fractures had acute autologous bone grafts.

MAIN OUTCOME MEASUREMENTS

The patient's extremity function was evaluated by the authors by using the Sanders et al. Distal Femur Functional Evaluation.

RESULTS

Sixteen of sixteen fractures healed. Two patients had delayed bone grafting for delayed union. Average frame time was twenty-five weeks. Average range of motion was 0 to 92 degrees. Five patients had less than 90 degrees of flexion. Five patients required a quadricepsplasty. Average follow-up was thirty-five months. One patient developed a pintract infection. One patient developed septic arthritis, and another developed osteomyelitis. The average Sanders et al. Function knee score was twenty-eight, with a maximum possible score of forty.

CONCLUSIONS

C3 fractures of the distal femur are associated with severe soft tissue injuries and bone loss. Loss of function appears to be directly related to these factors. Treatment with limited internal fixation and tensioned wire external fixation has equivalent results to other methods but has a higher incidence of infection and complications. Joint motion is retarded by binding of the soft tissues with fixation wires and pins. The technique is recommended only for salvage of severely comminuted and open fractures of the distal femur with extensive soft tissue injury. Distal femur fractures with moderate comminution and soft tissue injury should be treated with alternate methods.

Patellar tension band wiring: a revised technique

Using a modified AO tension band wiring technique to treat a patellar fracture has become popular and has achieved a high success rate. However, the technique of Kirschner wire insertion has not been considered in detail, which may migrate and consequently introduce fragments loss of reduction. A revised technique involving bending both ends of the Kirschner wires was prospectively studied. Sixty-eight consecutive patients were so treated, and 62 patients were followed-up for at least 2 years (range 2-6 years). All fractures healed with a union rate of 100% (62/62) and a union period of 2.5 +/- 0.5 months. Skin irritation was noted in 2 patients (3%). All patients achieved a satisfactory result. We therefore recommend this revised technique to treat all patellar fractures because of its high union rate and low complication rate.

Intraspinal migration of a Kirschner wire 3 months after clavicular fracture fixation

The authors describe a patient who had Kirschner (K-) wire osteosynthesis of a right lateral clavicular fracture and developed a tetraparesis after 3 months. Plain X-ray and CT scan showed an intraspinal migration of one K-wire through the intervertebral foramen of C5/6. The K-wire was pulled out through an opening of the wound over the right clavicle. No CSF fistula was seen. The patient recovered without any postoperative neurological deficit. Patients with K-wire osteosynthesis should be informed about the risk of dislocation and wandering and should regularly be seen in the outpatient clinic. Regular X-rays should be performed. The K-wires must be sufficiently bent at the distal end to prevent wandering into the proximal direction. The K-wires should be removed soon after 6 weeks and, in cases of dislocation and migration, as early as possible.

Intraosseous wire fixation versus rigid osseous fixation of mandibular fractures: a preliminary report

While wire osteosynthesis has been the accepted modality to use with open reduction of mandibular fractures, several authors have suggested the use of more rigid techniques to achieve the same result while also eliminating adverse effects associated with prolonged maxillomandibular fixation. Few studies have directly compared the two techniques in a prospective manner. The purpose of this paper was to evaluate complications seen with wire osteosynthesis versus a small bone plating system in management of mandibular fractures. The results suggest that small bone plating systems similar to the one used in this study may serve as a suitable alternative to wire osteosynthesis for the management of mandibular parasymphysis, body, and angle fractures. The length of the procedure, the length of hospital stay, and patient comfort were comparable with the two techniques. Factors that may contribute to failure are: location of the fracture, poor patient compliance, length of time from the trauma to the repair, antibiotic choice, and most importantly, operator skill and experience.

Anatomical considerations for percutaneous proximal humeral fracture fixation

PURPOSE

To investigate the hypothesis that percutaneous wire fixation of proximal humeral fractures is prone to regional neurovascular injury.

MATERIALS AND METHODS

40 cadaveric shoulders had percutaneous wires inserted from anterior and lateral humeral shaft entry points into the humeral head. The shoulders were then dissected to identify the neurovascular structures in this area.

RESULTS

The axillary nerve trunk and posterior circumflex humeral artery were found to be within the field of dissection. The axillary nerve was damaged on three occasions by the lateral wires, two of which were direct nerve penetrations. The anterior wires caused a single perineural injury of a terminal branch. The main neurovascular leash was 57 mm (range 35-70 mm) from the acromion tip laterally and 51 mm (range 35-85 mm) anteriorly, with a width of 6 mm (range 4-13 mm) laterally, and 12 mm (range 7-15 mm) anteriorly.

CONCLUSIONS

Percutaneous wire stabilisation is an attractive fixation option but this study highlights the close proximity of the important neurovasculature. Such fixation should be performed utilising a limited open approach, with dissection to bone under direct vision, with the subsequent use of a drill-sleeve for soft-tissue protection.

The risks of Kirschner wire placement in the distal radius: a comparison of techniques

A comparison of percutaneous and limited open insertion of Kirschner wires (K-wires) in the distal radius was conducted in an effort to determine which technique has the lower rate of iatrogenic injury. Eighty-eight K-wires were inserted in the distal radii of 44 fresh cadaveric arms: 44 at Lister's tubercle and 44 at the tip of the radial styloid. No incision was used for the percutaneous technique. The limited open technique included a 1.5-cm incision with blunt dissection and use of a soft tissue protector. To define the incidence of nerve or tendon damage secondary to pin placement, the cadaveric wrists were subsequently dissected under 3.5x loupe magnification. The distances from the K-wires to the branches of the superficial radial nerve and to the first 3 extensor compartments were recorded. Structures pierced or displaced by a K-wire were considered potentially injured. Chi-square analysis demonstrated a significantly higher rate of potentially injured nerves and tendons in the percutaneous group. Thus, to reduce the risk of potential injuries, limited open incision, blunt dissection down to bone, and the use of a soft tissue protector for K-wire placement into the distal radius is recommended.

Technical factors accounting for stability of a bilateral sagittal split osteotomy advancement: wire osteosynthesis versus rigid fixation

OBJECTIVE

Relapse after bilateral sagittal split osteotomy has been attributed to various technical factors that are inherent in the surgical procedure. The purpose of this article was to analyze technical factors that predispose to relapse when wire or rigid fixation is used.

STUDY DESIGN

Patients were randomized to either rigid or wire osteosynthesis. Cephalometric radiographs were obtained and digitized at multiple time periods before and after surgery. Data were analyzed through use of 2-sample t tests and stepwise regression analyses.

RESULTS

Multivariate analysis indicated that the following factors correlated with relapse: initial advancement, change in ramus in inclination, change in the mandibular plane, and fixation type.

CONCLUSIONS

Relapse increased with the amount of initial advancement and, to a lesser extent, with control of the proximal segment and change in the mandibular plane. These factors are similar for wire osteosynthesis and rigid fixation.

Potential risk of sternal wires

OBJECTIVE

To understand the potential fracture mechanism of sternal wires, we collected extracted stainless steel sternal wires from patients with sternal dehiscence following open-heart operations. Surface alterations and fractured ends of sternal wires were inspected and analyzed.

METHODS

Eight fractured and 12 non-fractured wires extracted from five patients (closure method: figure-of-eight or straight twisted; two without and three with mediastinitis) with mean implantation interval of 13.2+/-4.2 days (range 8-20 days) were studied by various techniques. The extracted wires were cleaned and the fibrotic tissues were removed. Irregularities and fractured ends were assayed by scanning electron microscopy and energy dispersive X-ray analysis (EDXA).

RESULTS

All examined fractured wires showed the presence of severe transversal cracks and crevice corrosion. EDAX revealed aluminum oxide inclusion on the fractured surface.

CONCLUSIONS

The synergic effect of stress and poor wire quality could be the precursors of material failure for the sternal wire.

Arthrodesis of the trapeziometacarpal joint

Over a 10-year period, 32 trapeziometacarpal (TM) joint fusions were performed in 29 patients, and reviewed. Pin fixation with tension band wiring was used in 14 cases, screws in eight cases, a plate in six cases, K-wires in three cases and staple fixation in one case. None was bone grafted. Splinting was applied for 4 to 5 weeks. There were four cases of delayed union (more than 2 months) and four cases of non-union requiring re-operation (12.5%). The average follow-up was 6 years and 7 months. Grip (26.5 kg) and pinch (4.9 kg) strength were respectively 7% and 18% less than the normal contralateral side. In bilateral osteoarthritis, grip and pinch were stronger than the contralateral side. Joint angulations measured on X-ray films showed for the peritrapezial joint an 18 degrees arc in flexion-extension (a reduction of 64% compared to the contralateral side) and 11 degrees of arc in abduction-adduction (a reduction of 72%). MP joint mobility increased in extension (160%), in flexion (23%), in abduction (120%), in adduction (157%). Despite the marked decrease in motion, subjective functional complaints were minimal. 78.1% of the patients were fully satisfied, 15.6% partly satisfied, and 6.3% dissatisfied. Pain was absent in 50% of the cases and very mild in 40.7%. Three patients complained of discomfort. Eight patients were noted to have osteoarthritic changes in the scaphotrapezial joint.

Mandibular fracture osteosynthesis: a comparison of three techniques

The authors report on a retrospective study of 205 consecutive patients at the Maxillofacial Unit of The Royal Melbourne Hospital to assess if adherence to Champy's principles in placement of miniplates in mandibular fractures minimises morbidity. 205 well documented cases of mandibular fractures treated with internal fixation, January 1985 to April 1990 were studied. The patients were assigned into three groups according to the type of fixation; 83 patients had miniplate fixation according to Champy's principles, 40 patients had miniplate fixation ignoring Champy's principles, 82 patients had transosseous wire (TOW) fixation. Outcome was measured by preoperative variables (age, gender, mechanism of fracture, site and number of fractures, nerve function, associated injuries and treatment delay) and postoperative variables (duration of admission, duration of intermaxillary fixation (IMF), malocclusion, infection, dehiscence, union, removal of fixation and nerve function which were assessed and compared. The results show that the preoperative variables were statistically similar in all groups. The postoperative variables indicated a statistically higher complication rate for the transosseous wire group compared with the miniplate groups, and morbidity was reduced in the group following Champy's principles. The morbidity rates in this study compare favourably with other studies even though the patients in this study had a much higher incidence of multiple fractures. Titanium miniplates appear as effective as miniplates constructed of other materials used in previous studies, especially when Champy's principles are followed.

Femoral artery and vein injury after cerclage wiring of the femur: a case report

Iatrogenic injuries to the vascular system are a rare but serious complication of primary and revision hip arthroplasty. These injuries usually occur during screw or retractor placement at the acetabulum or proximal femur. Although vascular injury during the passage of cerclage wires is a fear of all surgeons, its occurrence is yet to be described. This case report describes an unusual injury to the femoral artery and vein by a cerclage wire passed around the femoral midshaft during revision total-hip arthroplasty. It underscores the need for diligent comparison of preoperative and postoperative vascular examinations and emergent vascular surgery consultation when needed to avoid disastrous complications.

Tension band arthrodesis of small joints in the hand

Two-hundred three patients underwent 290 tension band arthrodeses of the metacarpophalangeal and proximal interphalangeal joints of the hand. Nine patients (3%) failed to achieve bony union, four had painless pseudarthroses, and one patient had a small finger amputation. Twenty-five fusions (9%) required hardware removal. There were 10 superficial infections (all responded to oral antibiotic therapy), and three fusions were malrotated. Tension band arthrodesis is our choice for fusion of the metacarpophalangeal and proximal interphalangeal joints. It is reliable and provides stable fixation, pins do not protrude, and external splinting is unnecessary in the cooperative patient.

Superficial radial nerve damage due to Kirschner wiring of the radius

For displaced fractures of the radius, the use of Kirschner wires (K Wires) is accepted practice either alone or to supplement external fixation. Complications related to K wires include infection, migration and damage to tendons and nerves. We set out to investigate to incidence of superficial radial nerve damage due to radial styloid K wires. Injury to the sensory branch of the superficial radial nerve was seen in eight (20%) out of the 40 patients. K wiring is a popular technique to help maintain anatomic reduction of distal radial fractures. It has the advantage of being a semi-closed procedure, which is simple to perform. However, the morbidity of nerve damage is often underestimated and can be avoided.

Severe late-onset epistaxis following Le Fort I osteotomy: angiographic localization and embolization

Epistaxis following maxillofacial trauma or maxillofacial surgery is uncommon. It usually occurs within 24 hours of the injury and can usually be controlled by packing. Rarely internal maxillary artery ligation is necessary and embolization has been used in some cases of severe trauma. We present a case of severe late-onset epistaxis following Le Fort I osteotomy. The diagnostic approach and treatment are discussed.

A prospective study on changes in the sensibility of the oral mucosa and the mucosa of the upper lip after Le Fort I osteotomy

A prospective study on 21 patients was performed in order to investigate the changes in the sensibility of the oral mucosa and the mucosa of the upper lip after a Le Fort I osteotomy. Patients were followed-up 1 month, 3 months and 6 months postoperatively. The sensibility of the mucosa was tested using electrical sensimetry (Laitinen, 1987). The teeth were tested with carbon dioxide snow (Obwegeser and Steinhäuser, 1963). A picture of the marked hypoaesthetic area was performed and magnified 1:1 if a hypoaesthesia of the cutaneous distribution of the infraorbital nerve was found. The area was measured using a Macintosh II CX computer. It was demonstrated, that after 3 months the infraorbital nerve regained its function completely. The greater palatine nerve and the posterior superior alveolar nerve demonstrated an incomplete recovery of sensory function after 6 months. After 6 months 92.8% of the teeth reacted to carbon dioxide snow. Within the first 6 months postoperatively, no pulpe necrosis was observed. No correlation could be found between the amount of anterior maxillary movement and the degree of hypoaesthesia of the infraorbital nerve. Dentate Le Fort I osteotomies showed a better sensory regeneration of the greater palatine nerve than edentulous Le Fort I osteotomies. After Le Fort I osteotomies in 2 parts, more hypoaesthesia of the greater palatine nerve was observed than after Le Fort I osteotomies in 1 part. After miniplate osteosynthesis, more hypoaesthesia of the posterior superior alveolar nerve was observed than after wire osteosynthesis. The results are discussed and compared with the results found in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)

Retrospective study of nonsyndromic craniosynostosis treated over a 10-year period

Since the first operation for premature suture closure in North America in 1888, there have been some fundamental changes in the treatment of these sutures, the latest being the U.S. Food and Drug Administration's 1996 approval of a bioabsorbable fixation device. This retrospective study documents our experience with procedures performed primarily by Bennie J. van R. Zeeman for isolated craniosynostosis over a 10-year period. It was an attempt to evaluate factors affecting outcome and to determine the safety of the techniques used to correct these congenital defects. Diagnoses included plagiocephaly (116) and sagittal (44), metopic (17), and bilateral coronal (12) synostosis. All patients underwent fronto-orbital advancement or calvarial vault remodeling, or both. The average patient age at time of sagittal synostosis surgery was 13.4 months; unilateral coronal synostosis, 12.2 months; deformational plagiocephaly, 9.8 months; metopic synostosis, 8.6 months; and bilateral coronal synostosis, 10.4 months. Perioperative complications were minimal, with one mortality. Postoperative complications included three cases involving infection. The problem of reoperation for the removal of wires and plates remains the greatest postoperative complication. Because of poor patient compliance, no accurate postoperative follow-up has been recorded. On the basis of our experience, we wish to point out some problems inherent in this surgery and also the complications that can occur despite careful coordinated planning and team effort.

Craniocervical junction instability: instrumentation and fusion with titanium rods and sublaminar wires. Effectiveness and failures in personal experience

BACKGROUND

The aim of the study was to evaluate the effectiveness, pitfalls and failures of instrumentation and fusion with titanium wires and rods in 12 h patients with craniovertebral junction instability.

METHODS

Among nine adult patients (mean age 48.11 years) with craniovertebral junction instability, four had basilar impression, three metastatic disease, one rheumatoid arthritis and one Down's syndrome. Three children (mean age 7.33 years) with genetic (Down's syndrome, 2 cases) and metabolic (mucopolisaccarydoses type IV, i.e. Morquio Syndrome, 1 case) disease were studied as well. Each patient underwent preoperative radiological evaluation by means of X-Ray, CT scan and MRI of the craniocervical region. Occipitocervical instrumentation with a titanium U-shaped wired rod was performed in each patient. Autologous bone fusion was performed in all but the two cancer patients, in whom polymethylmetacrylate was used. Postoperatively, all the patients used an external orthosis for 3-6 months. Post-operative X-Ray, CT and MRI were performed on each patient. The Frankel clinical scale was used to asses the outcome at follow-up which ranged from 1 to 10 years. At maximum follow up, there was either clinical improvement or stabilization recorded in all but one patient. This patient with basilar impression transiently worsened from grade D to C and a spinal cord lesion was already evident before the operation on MRI examination.

INTERPRETATION

The effectiveness of surgical management of craniovertebral junction instability by instrumentation and fusion was demonstratedly in our experience. Nevertheless, the choice of the surgical technique should be made with caution when a spinal cord lesion is revealed by preoperative neuroimaging studies.