Aim

The origin of surgical site and biomaterial-associated infection is still elusive. Microorganisms contaminating the wound may come from the air, the surgical team, or from the skin of the patient. Prior to surgery the skin of patients is disinfected, but bacteria deeper in the skin (e.g. in sweat glands or sebaceous glands), may not be reached. This study aims to assess a potential role of this intracutaneous bacterial reservoir in biomaterial-associated infection.

Objectives

Current studies on the additional benefit of using computed tomography (CT) in order to evaluate the surgeons’ agreement on treatment plans for fracture are inconsistent. This inconsistency can be explained by a methodological phenomenon called ‘spectrum bias’, defined as the bias inherent when investigators choose a population lacking therapeutic uncertainty for evaluation. The aim of the study is to determine the influence of spectrum bias on the intra-observer agreement of treatment plans for fractures of the distal radius.

Summary

In contrast to the current literature, myofibroblasts are not present in chronic posttraumatic elbow contractures.

However, myofibroblasts are present in the acute phase after an elbow fracture and/or dislocation. This suggests a physiological role in normal capsule healing and a potential role in the early phase of posttraumatic contracture formation.

Background: Complex fractures of the tibial plateau can be difficult to characterize on plain radiographs and two-dimensional computed tomography scans. We tested the hypothesis that three-dimensional computed tomography reconstructions improve the reliability of tibial plateau fracture characterization and classification.

Methods: Forty-five consecutive intra-articular fractures of the tibial plateau were evaluated by six independent observers for the presence of six fracture characteristics that are not specifically included in currently used classification schemes:

posteromedial shear fracture;

In addition, fractures were classified according to the AO/OTA Comprehensive Classification of Fractures, the Schatzker classification system and the Hohl and Moore system. Two rounds of evaluation were performed and then compared. First, a combination of plain radiographs and two-dimensional computed tomography scans (2D) were evaluated, and then, four weeks later, a combination of radiographs, two-dimensional computed tomography scans, and three-dimensional reconstructions of computed tomography scans (3D) were assessed.

Results: Interobserver agreement improved for all classification systems after the addition of three-dimensional reconstructions (AO/OTA κ2D = 0.536 versus κ3D = 0.545; Schatzker κ2D = 0.545 versus κ3D = 0.596; Hohl and Moore κ2D = 0.668 versus κ3D = 0.746).

Three-dimensional computed tomography reconstructions also improved the average intraobserver reliability for all fracture characteristics, from κ2D = 0.624 (substantial agreement) to κ3D = 0.687 (substantial agreement). The addition of three-dimensional images had limited infiuence on the average interobserver reliability for the recognition of specific fracture characteristics (κ2D = 0.488 versus κ3D = 0.485, both moderate agreement). Three-dimensional computed tomography images improved interobserver reliability for the recognition of coronal plane fractures from fair (κ2D = 0.398) to moderate (κ3D = 0.418) but this difference was not statistically significant.

Conclusions: Three-dimensional computed tomography is helpful for;

individual orthopaedic surgeons for preoperative planning (improves intraobserver reliability for the recognition of fracture characteristics), and for

Background: Extra-articular fractures of the distal radius in children are most often treated with closed reduction and cast immobilization. The purpose of this retrospective study was to evaluate long term (> 12 years follow-up) objective and subjective outcomes in a consecutive series of pediatric patients treated with closed reduction with standardized outcome instruments. We hypothesized that children treated with closed reduction and cast immobilization have little or no objective functional impairment in later life and therefore subjective factors are the strongest determinants of outcome.

Methods: Twenty-seven patients with an average age at time of injury of 9 years (range, five to sixteen years) were evaluated at an average of twenty-one years (range, twelve to twenty seven years) after injury (patients aged 21 to 39) after closed reduction of an extra-articular distal radius fracture. Patients were evaluated using 2 physician-based evaluation instruments (modified Mayo wrist score; MMWS, and the Sarmiento modification of the Gartland and Werley score; MGWS) and an upper extremity-specific health status questionnaire (Disabilities of the Arm, Shoulder and Hand; DASH) questionnaire. Radiographic measurements were also made. Multivariable analysis of variance and multiple linear regression modelling were used to identify the degree to which various factors affect variability in the scores derived with these measures.

Results: All fractures had healed without significant loss of alignment. Final functional results according to the MGWS were rated as excellent or good in all patients. The average MMWS score was 90 points, and the median DASH score was 0 points. Twenty patients (74%) considered themselves pain free. Bivariate analysis revealed pain -as rated according to scales used in the MMWS- and age at time of injury to be correlated with DASH scores, with pain as the only independent predictor of patient-based outcome in multivariable analysis. This explains almost three quarters of the variability in DASH scores. Pain, range of motion, and radiographic measurement of radial length correlated with the physician based scoring system MMWS;

Conclusions: Twenty-one years after injury 96% of patients have a satisfactory outcome according to physician-based MMWS categorical ratings and patient-based DASH scores. It is remarkable that pain explained 74% of the variation in DASH scores. Perhaps when there is very little impairment, subjective factors are more important determinants of disability.

Background: It is well established that unstable fractures of the distal part of the radius may require operative treatment to restore alignment and that failure to restore alignment often leads to wrist and forearm dysfunction. There is ongoing debate in the literature whether or not there is a strict relationship between the quality of anatomical reconstruction and functional outcome. We hypothesize that there is no difference in objective- and subjective functional outcome between patients with AO type B versus more complex AO type C fractures.

Methods: Ninety-four patients with an average age of 42 years (range, 20 to 78 years) at the time of injury were evaluated an average of 20 years (range, 8 to 32 years) after treatment of an intra-articular distal radius fracture. At long-term follow-up patients were evaluated using a physician-based evaluation instruments (modified Mayo wrist score; MMWS and an upper extremity-specific health status questionnaire (Disabilities of the Arm, Shoulder and Hand; DASH) questionnaire. Objective and subjective functional outcome of patients with AO Type B and AO Type C fractures were compared.

Results: An average of 20 years after injury (average age 62 years, range 35 to 90), all fractures healed without significant loss of alignment. There was no difference in physician based outcome measure according to the Mayo score between 17 patients with 18 AO type B fractures (average, 80,3 points; range 45 to 100) and 27 patients with 31 AO type C fractures (average, 75.9 points; range 10 to 95, p=0.42). Differences in subjective DASH scores were not statistically significant either (p = 0.47); average 13 points for Type B patients (range, 0 to 58 points) and an average of 16 points for Type C patients (range, 0 to 71 points).

Groups were statistically comparable. No statistical differences were found in flexion extension arc (average 103 degrees, range 10 to 145 degrees), pronation supination arc (average 150 degrees, range 0 to 180 degrees) or radial ulnar deviation (average 52 degrees, range 0 to 85 degrees), as well as grip strength and osteoarthritis (all p> 0.05)

Conclusions: Twenty years after injury 67% of patients have a satisfactory outcome according to physician-based MMWS categorical ratings. There is no difference in functional long term outcome between patient with more extensive intra-articular comminution (type C fractures) and AO type B fractures. This is consistent with previous long term outcome studies with similar methodology; when more complex injuries are not correlated with decreased long term functional outcome, other (subjective) factors are more important determinants of disability.

New concepts in plate fixation have led to an evolution in plate design for olecranon fractures. The purpose of this study was

to compare the stiffness and strength of a contoured Locking Compression Plate (LCP) with a conventional plating method (one-third tubular plate) in a cadaveric comminuted olecranon fracture model with standardized osteotomy, and

In the biomechanical study, five matched pairs of cadaveric elbows were randomly assigned for fixation by either LCP or a conventional plating method. Specimens were mounted to a custom-made testing bench and subjected to cyclic loading until failure occurred while measuring gapping at the osteotomy site. In the clinical study, twenty-one patients treated with LCP for complex olecranon fractures had a mean follow up of 20 months (3–39 months) and functional and patient rated outcome were evaluated.

In the biomechanical study, there was no significant difference in fixation stiffness and strength between one third tubular plating and LCP (p > 0.05). In the clinical study, the mean time to union of the fracture was 6 months (2–28 months). According to the Mayo Elbow Performance Index (MEPI) most patients had a good or excellent outcome. No patients reported difficulty with activities of daily living. Physical capacity showed minimal loss of stability and strength. Six patients had their hardware removed.

Technical ease of application and advantageous features of the LCP -such as unicortical screw fixation and improved holding power in osteopenic bone- make it a good alternative implant for comminuted olecranon fractures.

Aims: The purpose of this study was to quantify the amount of cell viability and cartilaginous damage present in non-reparable human osteoarticular fragments removed at the time of acetabular fracture surgery. Material and Methods: The cases of 6 patients with comminuted fractures of the acetabulum were prospectively analyzed. Average age was 39 years, and none of them had evidence of preexisting hip pathology. Loose small osteoarticular fragments that were not reparable were microscopically analyzed to assess in-situ cell viability. Observations were divided into (i) depth of chondrocyte death from the articular surface, and (ii) structural matrix damage and cell death under regular histology. The depth of cell death was classiþed as mild between 1 and 15%, moderate from 15 to 30%, severe from 31 to 60% and total from 61 to 100%. Results: Five of the patients were classiþed as having only mild amount of chondrocyte death and one specimen had a moderate amount of chondrocyte death. The articular surface damage was mainly located on the superþcial zone of the cartilage. Discussion and conclusion: Most of the chondrocytes on small osteochondral fragments removed from displaced intraarticular acetabular fractures were still viable after having received a substantial amount of trauma.

Aims: To determine the results of Òbiologic þxationÒ with a minimally invasive plating technique using a newly designed low proþle ÒScallopÒ plate in the treatment of pilon fractures. Methods: 17 patients were treated between 1999 and 2001 for a tibial plafond with a newly designed ultra-slim plate. Eleven (65%) were high-energy injuries, two were open. Staged open reduction and þxation of the þbular fracture and application of an External Fixator was performed in 12 cases. As soon as the soft tissues and swelling allowed, the articular surface was reconstructed and anatomically reduced, if necessary through an small incision, and the articular block was þxed to the diaphysis using a medially placed, percutaneously introduced ßat Scallop plate. Time to healing and complications were evaluated. Quality of the results and outcome were graded using the Ankle-Hindfoot-Scale. Results: All patients went on to bony union at an average time of 14.1 weeks. There were no plate failures or loss of þxation/ reduction. Two superþcial wound-healing problems resolved with local wound care. At an average FU of 17 months eight patients (47%) had an excellent, seven (41%) a fair and two (12%) a poor result. The average AHS was 86.1. Conclusions: Based on these initial results, it appears that a minimally invasive surgical technique using a new low proþle plate can decrease soft tissue problems while leading to fracture healing and obtaining results comparable with other more recent series. We believe that this new ÒScallop PlateÒ is appropriate for the treatment of pilon fractures and should be used in conjunction with a staged procedure in the acute trauma setting.

Osteonecrosis of the femoral head can be caused by a variety of disorders and affects the relatively young patient. Most studies have concentrated on the femoral changes; the sites of early lesions of the labrum and acetabular cartilage have not been recorded. We studied 17 hips with osteonecrosis and a wide congruent joint space on radiographs and by direct inspection of the femoral head, labrum and acetabular cartilage during surgery. All of the femoral heads had some anterosuperior flattening which reduced the head-neck ratio in this area. A consistent pattern of damage to the labrum and the acetabular cartilage was seen in all hips. Intraoperatively, impingement and the cam-effect with its spatial correlation with lesions of the labrum and acetabular cartilage were observed. These findings could be helpful when undertaking conservative surgery for osteonecrosis, since the recognition of early radiologically undetectable acetabular lesions may require modification of the surgical technique.

Lipoma arborescens is a rare intra-articular lesion, characterised by diffuse replacement of the subsynovial tissue by mature fat cells, producing prominent villous transformation of the synovium. The aetiology of this benign condition is unknown.

We describe six cases involving the knee discussing the symptoms, diagnosis and treatment.