Purpose of the study: Loss of acetabular bone stock is a very common finding at revision total hip arthroplasty (rTHA). The acetabular bone defect can be filled with an autograft or with cyropreserved or lyophilized and radiated allografts. The permanent availability lypophylized radiated allografts is a certain advantage. For more than ten years (1994), we have used Phoenix® (TBF) lyophylized radiated bone grafts.

Material and methods: We conducted a retrospective study of all patients who underwent rTHA for aseptic loosening between 1994 and 1999 with replacment of the acetabular implant requiring use of a lyophyilized radiated allograft (TBF, Phoenix®) fashioned from femoral heads and cut to fit. Grafts were impacted followed by acetabulra replacement with a cemented polyethylene (PE) cup or a Kerboull retaining ring, or an ace-tabular grid as needed. This procedure was used for 18 hips (16 patients). The Postel-Merle-d’Aubigné (PMA) clinical score and radiographic assessment were noted at five years with the Paprovsky classification. In addition, the status of the allograft (homogeneous aspect) and the presence of a lucent line between the host bone and the allograft were noted.

Results: One patient was lost to follow-up. The analysis thus included 17 of 18 hips. Mean age was 63 years at rTHA surgery and 55 years at primary surgery. The reason for revision was cup loosening (n=13), isolated PE wear (n=4) with acetabular bone defects. The mean preoperative PMA score was 10.4 (range 5–18). At three months, the PMA score was 15.2 (range 12–18), at one year 16.2 (range 15–18), and at five years 17.2 (range 16–18). Implant migration was not observed on the five-year x-rays. Allografts were incorporated for seven hips which presented a homogeneous graft image. Five hips presented a partial lucent line and five a complete lucent line but with no evidence of implant instability. None of the patients required surgical revision to change the implant or for a new bone graft.

Discussion: Acetabular revisions are often associated with bone defects which can be filled with allografts. This study demonstrated the good incorporation of lyophilized radiated allografts. This incorporation is progressive with good implant stability at more than five years. Use of this graft material for filling acetabular defects can correct for the bone deficiency.

Conclusion: Use of lyophilized grafts gives satisfactory results with reliable outcome at five years comparable with other bone replacement methods, particularly cyropreserved femoral grafts used before 1994.

Purpose of the study: Prenatal screening and search for risk factors has lead to early diagnosis of congenital hip dysplasia. The percent of excentration of the dysplastic hip can be quantified with ultrasonography. The purpose of this study was to evaluate the usefulness of ultrasound monitoring of confirmed hip dysplasia as a method for determining the appropriate time to discontinue treatment.

Material and methods: We collected a series of patients presenting unstable hips one month after birth. Ultrasonographic examinations were performed to quantify the instability. Initial treatment was forced abduction. If the infant’s weight was greater than 5.6 kg, a Pavlik harness was used. Physical examination and control ultrasound examinations were performed at 4, 8 and 12 weeks. Forced abduction and ultrasound surveillance were discontinued when the percent of acetabular cover was greater than 50%. Long-term surveillance consisted in physical examination and plain ap view of the pelvis at four months and at onset of walking.

Results: Ultrasound monitoring was instituted for 71 hips in 51 patients. Mean age at onset of the monitoring scheme was 37.7 days (range 38–74 days). Mean acetabular cover, as evaluated by ultrasound before treatment, was 35.5% (range 20–45%). After four weeks, mean cover for 42 hips was 54.7% (range 50–85%). For the other 29 hips, mean acetabular cover was 41.4% (range 36–47%) at four weeks. At eight weeks, 26 of these 29 hips had a mean cover of 60% (52–85%). Acetabular cover remained below 50% for three hips at twelve weeks. Mean HTE at four months was 20.7° (range 10–26°). At walking, all hips were centered and no irregularities were noted on the x-rays of the femoral nucleus.

Discussion: The majority of infants with unstable hips diagnosed at birth achieve spontaneous cure without treatment. For others, cure can be achieved with forced abduction but with a risk of osteochondritis. In our study, ultrasound monitoring enabled a reliable assessment of the proper moment to interrupt treatment.

Conclusion: Ultrasound examination of the hip joint is a satisfactory method for monitoring hip dysplasia in infants aged less than four months. It appears to be useful for determining the moment to interrupt treatment.

Purpose of the study: We describe a surgery navigation system based on virtual fluoroscopy images established with a 3D optic localizer. The purpose of this work was to check the accuracy of the system for posterior spinal implants in comparison with conventional surgery. Duration of radiation and duration of surgery were compared.

Material and methods: A 3D optic localizer was used to monitor the position of the instruments in the operative field, as well as the fluoroscopy receptor. The surgeon took two views, ap and lateral, with a total exposure of two seconds. The C arm was then removed. After image correction, the ap and lateral views were displayed on the work station screen where the computer superimposed to tools on each image. Twenty osteosynthesis procedures for implantation of pedicular screws via a posterior approach to the thoracolumbar spine were performed with this virtual fluoroscopy technique (20 patients, 68 screws). During the same study period, twenty other procedures were performed with the conventional technique (ap and lateral x-ray with the C-arm after drilling the pedicle, 20 patients, 72 screws). The position of the spinal implants was compared between the two series on the ap and lateral views and postoperative CT. Similarly time of exposure to x-rays and duration of the surgical procedure were recorded.

Results: The rate of strictly intrapedicular implantation was less than 8% (5/68 screws) in the virtual fluoroscopy series versus 15% (11/72 screws) in the conventional series. Time of exposure to radiation was significantly lower in the virtual fluoroscopy series with a 1 to 3 improvement (3.5 s versus 11.5 s on average) over the conventional method. With training, this method is not more time consuming (10 min per screw for the conventional method versus 11.25 min for virtual fluoroscopy).

Discussion and conclusion: Compared with conventional fluoroscopy, the virtual technique enables real time navigation while significantly reducing the dose of radiation, both for the patient and the surgery team. There are two types of advantages of virtual fluoroscopy over CT-based systems: first virtual fluoroscopy is immediately available without specific preoperative imaging and secondly it provides real non-magnified images acquired once during the procedure, after which the C-arm is removed. 3D virtual fluoroscopy is probably the next step but requires further experience.

Purpose of the study: Appropriate treatment of displaced supracondylar fractures of the distal humerus in children remains a controversial topic. Blount reduction followed by percutaneous or open pin fixation have been widely used. The purpose of this study was to analyze outcome after open surgical treatment of these fractures in pediatric trauma victims.

Material and methods: The study included all pediatric patients who underwent surgical treatment for displaced supracondylar fractures of the distal humerus over a ten year period. Fractures were classified III or IV according to Lagrange and Rigault. Cross pinning was used in all cases, via a posterior approach or a double lateral and medial approach. The mechanism of the fracture and pre- and postoperative vascular and neurological complications were noted. The long-term assessment included standard x-rays of the elbow joint (ap and lateral views) and a physical examination to search for misalignment and residual neurological disorders.

Results: We identified 110 patients, 61 boys and 49 girls, mean age 7.61 years (range 2–15 years). There were 96 grade IV fractures and 24 grade III. Mechanisms were: sports accident (n=44), fall from height (n=36), fall from own height (n=30). A neurological complication was observed in 29 children, skin opening in three and regressive vascular damage in six. A posterior approach was used for 95 patients and a double approach for 15. There was one revision for secondary displacement. Five patients developed transient paresthesia of the ulnar nerve which resolved without sequela. Three patients presented a moderately hypertrophic or deformed callus which had little functional impact. One patient with an open fracture required surgerical arthrolysis for stiffness six months after fracture.

Discussion and conclusion: Open surgery is a very reliable treatment for supracondylar elbow fractures with a low rate of short- and long-term complications. Ulnar nerve palsy, the classical complication of percutaneous cross pinning, can be attributed to the medial pin (7–16% of cases in the literature). The Blount method and Judet or Métaizeau fixations can sometimes be complicated by secondary displacement or a deformed callus, complications which were almost never observed in our series. The results obtained in this series favor our approach for open surgery for the treatment of displaced supracondylar fractures of the distal humerus in children.