Introduction

Proximal humeral shaft fractures are rare injury. In such case, to the best of our knowledge, the treatment by both double-plate method and the MIPO has never been seen before in the literature. Here we report our experience and management about this method.

Introduction

The treatment of large segmental defects of long bones, which is caused by high energy trauma, revision surgery and resection of tumor or osteomyelitis and so on, is usually difficult. Recently the usefulness of Induced membrane technique (Masquelet technique) is reported. Induced membrane technique is an alternative method to reconstruct long-bone defects, which is two-stage surgery and combines the use of induced pseudo-membranes and cancellous autografts. The mechanism of bone formation in this technique is unknown. We performed Induced membrane technique on four patients, collected their membranes, and tested osteogenic ability and multipotency of cells derived from the membrane.

Purpose: The purpose of this study was to evaluate a new ONI Elbow Plate System for intra-articular fractures of the distal humerus in the elderly.

Methods: 10 elder patients with complete intra-articular distal humerus fractures were treated by our new fixation system. The mean age of our patients was 76 years old (range 70 to 88 years). According to the AO/ASIF system, 6 cases were type C1, three cases were C2 and one case was C3. The ONI transcondylar plate conforms to the anatomical contour of the lateral column of the distal humerus and a locking mechanism between the plate portion and the transcondylar screw and the ONI medial plate conforms to the anatomical contour of the medial one (ONI Elbow Plate System). In all cases the ONI transcondylar plate was used at the lateral side of the fracture site, and either a cannulated cancellous screw (n=3) or an AO one-third tubular plate (n=4) or the ONI medial plate (n=3) at the medial side. The mean period of follow up was 32 months (24 to 48 months).

Results: In all of the 10 cases, complete union was seen on radiographs, and alignment was almost maintained postoperatively. The assessment of results according to the modified Cassebaum’s rating score was 90.4. There were no cases of nonunion or malunion.

Conclusion: Our data showed that the ONI Elbow System for treatment of this fracture in the elderly produced consistently good results even in cases with a small osteoporotic fragment of the distal humerus

Introduction: Although prophylactic antibiotic administration is common in spinal surgery, the choice of drug, dose, and timing of administration often varies. Little is known about the activity of antibiotics in the spine and indeed if they are distributed throughout the disc and if the time intervals are optimal. Because infections that produce iatrogenic discitis generally arise within the disc, the antibiotic concentration of the disc is more relevant than serum concentrations. The aims of the study were to determine if a 2g dose of cephazolin was effective at preventing discitis over a four-hour period in immature ovine discs that were both non-degenerate and degenerate; and also to determine the concentration of cephazolin in serum and disc tissue.

Methods: In 10 Merino wethers aged 12 weeks, three lumbar discs were “degenerated” by incising the posterolateral annulus with a scalpel blade and using ronguers, removing the bulk of the nucleus pulposus. After 12 weeks nine animals were anaesthetised and given a 2g dose of cephazolin (David Bull Laboratories, Australia) at predetermined time intervals over a four-hour period. The antibiotic was chosen for effectiveness against Staphylococcus aureus a common discitis-causing organism. One sheep (control) did not receive any antibiotics to follow the natural progression of infection. All animals had discography with radiographic contrast that contained S. aureus at two incised levels and at two non-incised levels. Lateral radiographs of the lumbar spine were taken at two, six and 12 weeks to monitor the bony changes. At 12 weeks all sheep were given a 2g intravenous dose of cephazolin at time intervals before being killed. The spines were removed and prepared for light microscopy to assess pathology of the discs and for biochemical analysis of antibiotic concentration. Success of treatment was judged using histologic and radiographic features.

Results: The control sheep that did not receive any antibiotics developed discitis at four levels. Histology at 12 weeks confirmed discitis in 10/36 “prophylactic discs”. Of these “prophylactic discs” 7/10 had previously been “degenerated”. Discitis only developed in immature discs that were administered cephazolin two hours prior to inoculation. When antibiotic was administered after inoculation discitis was prevented. Biochemistry results confirmed that antibiotic diffused throughout the disc but was concentrated in the annulus more than the nucleus. Antibiotic levels in the disc peaked at 15 minutes (annulus mean concentration 15.5 mg/L, nucleus mean concentration 3.2 mg/L). Serum levels at 15 minutes were up to 50 times greater at this time (serum mean concentration 178 mg/L).

Discussion: The discs that were “degenerate” had a higher incidence of discitis compared to “non-degenerate” discs. However the concentration of antibiotic in degenerate discs was not significantly different than in non-degenerate discs. A 2 gram dose of cephazolin is reasonably effective (approx 70% success rate) at preventing discitis over a four-hour period.