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Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_29 | Pages 67 - 67
1 Aug 2013
de Lange P Birkholtz F Snyckers C
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Purpose of the study:. Is circular external fixation a safe and effective method of managing closed distal third tibia fractures. These fractures are conventionally treated with plaster casts, intramedullary nails or plate fixation. These treatment modalities have complication rates in the literature of up to 16% malunion, 12% non-union, and 17% deep infections. Description and Methods:. Retrospective review of 18 patients with closed distal third tibia fractures, with or without extension into the ankle joint, treated with circular fixator systems and minimal percutaneous internal fixation of the intra-articular fragment if required. Patients were followed up for time to union, malunion incidence as well as incidence of pin tract and deep infection. Distal third fractures which were extra articular or with simple intra articular extension were included. (AO 43 A, B1, C1, C2 + AO 42 in distal third) Patients with pilon fractures (AO 43 B2, B3 and C3) were excluded. Summary of results:. The average time to union in these patients was 16 weeks (11–33 weeks). The non-union rate was 11.1% in comparison to 12% with conventional treatment. The malunion rate was 0% compared to 16% with conventional treatment. The incidence of pin tract infection was 16.6%, but no deep infections were noted, whilst conventional treatment shows deep infection in up to 17%. Conclusion:. Circular external fixation is a safe and efficient option in the treatment of distal tibia fractures. The incidence of complications is significantly reduced in comparison to conventional treatment


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 122 - 122
1 May 2016
Patel R Zumbrunn T Varadarajan K Freiberg A Rubash H Muratoglu O Malchau H
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Introduction. Dual-mobility (DM) liners have increased popularity due to the range of motion and stability provided by these implants. However, larger head diameters have been associated with anterior hip pain, due to surrounding soft-tissue impingement, particularly the iliopsoas. To address this, an anatomically contoured dual mobility (ACDM) liner was designed by reducing the volume of the liner below the equator (Fig1). Previous cadaver studies have shown that the ACDM significantly reduces iliopsoas tenting and trapping of the liner compared to conventional designs. We created a finite element study based on previous cadaver testing to further analyze the effectiveness of the ACDM design in reducing soft-tissue impingement, specifically the tendon-liner contact pressure and the tendon stress. Methods. The finite element model was developed within COMSOL 4.3b. The psoas tendon was modelled as a Yeoh hyper-elastic Material, which uses 3 constants (c1-c3), density (1.73g/cm3) and a bulk modulus (26GPa)[Hirokawa,2000]. In a previous, separate study, the average stiffness of 10 psoas tendon samples (5 cadavers), were measured to be 339[N/mm] in the linear region with average width and thickness of 14mmX4mm. The 3 constants were tuned to match experimental uniaxial test data, and were 5[GPa], 0[Gpa], and 46[GPa] for c1, c2, and c3 respectively. The implant components were rigidly modeled relative to the psoas. Cadaver specific CT models were used to create the FEA geometry. The insertion points for the Psoas were digitally determined on the proximal end of the lesser trochanter, and the psoas notch on the pelvis for hip flexion angles of −15°, 0°, 15° and 30°. These insertion points determined the length of the psoas and its relative position to the femoral head in 3D. The specific liner size and position for each cadaver was determined by implant planning with the CT models. In this abstract, we only present data for 2 specimens (left/right hips) with 44mm conventional DM, and 44mm ACDM, matching specimen anatomy. A 500N tensile load was applied to the psoas tendon proximally to simulate moderate physiological loading, the average/max stresses and contact pressures between the psoas and the two liner designs were determined. Results. At all flexion angles from −15° to 30°, the ACDM had lower psoas-liner contact pressure and stress compared to the conventional liner. Both contact pressure and tendon stress decreased for both liners with increasing hip flexion. At −15° flexion angle, there was an average contact pressure difference of .51MPa between the conventional and ACDM designs, or 37% decrease in pressure when using the ACDM. The average difference in tendon stress was 67.9MPa, or a 59% decrease in stress when using the ACDM (fig2, fig3). Conclusion. This study utilized cadaver specific FEA models to evaluate interaction between the iliopsoas tendon and conventional and ACDM liners. Although this abstract presented FEA models for only four hips (two specimens), the results show a notable reduction in contact pressure and tendon stress with ACDM designs. This validates findings from previous cadaver studies, suggesting that anatomically contoured designs could reduce anterior hip pain and soft tissue impingement


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_17 | Pages 82 - 82
1 Dec 2018
Hackl S Greipel J Von Rüden C Bühren V Militz M
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Aim. Posttraumatic pelvic-osteomyelitis is one of the most serious complications after pelvic-fractures. The necessary extensive surgical debridement as part of interdisciplinary treatment is complicated by the possible persistence of pelvic instability. The aim of this study was to determine the outcome and outline the course of treatment after early posttraumatic pelvic bone infections due to type-C pelvic ring injuries. Method. In a retrospective cohort study (2005–2015) all patients with pelvic-osteomyelitis within six weeks of surgical stabilization of a type-C pelvic-fracture were assessed. Microbiological results, risk factors, course of treatment and functional long-term outcome using the Orlando-Pelvic-Score were analyzed. Results. A total of 18 patients (age 43.7 years; Body-Mass-Index 27.9 kg/m2; ASA-physical-status 1.8; Injury-Severity-Score 38) developed a pelvic-osteomyelitis within an average of 27 days after internal surgical stabilization of a type-C pelvic injury (AO-type C1: 10, C2: 4, C3: 4). Os pubis was affected in 7 and Os ilium in 11 cases. In addition to the pelvic-fracture, major vascular injuries occurred in 8, nerve injuries in 9, and intestinal and/or bladder ruptures in 11 cases. In 14 cases a mass transfusion was necessary. In addition to clinical signs of inflammation, (10 × redness, 12 × wound secretion, 6 × fistula) elevated levels of c-reactive-protein (7.7 mg/dl) and white-blood-cells (10.5/nl) were found. Bacterial cultures harvested during the initial surgical revision demonstrated mixed cultures in 17/18 cases, with an average of 3 different organisms isolated per case (61% intestinal bacteria). During the scheduled repetitive debridement a reduction of the initial mixed cultures into a single organism was observed. Overall 6.8 surgical interventions, including implant removal, were necessary until osteomyelitis was eradicated. In no cases was re-osteosynthesis performed. In 6/18 cases recurrence of infection occurred after an average of 5 months, followed by an additional repetitive debridement. An average 3-year-follow-up after the initial osteomyelitis-diagnosis demonstrated eradication of infection in 17/18 cases combined with an Orlando-Pelvic-Score of 21.9 points (best possible function: 40 points). Despite significant pelvic malalignment the ability to walk was achieved in all patients, with one exception due to a spinal cord injury. Conclusions. Despite no new surgical stabilization of the initial unstable pelvic injury, the early removal of implants combined with extensive debridement and antibiotic therapy led to sufficient long-term outcomes in patients with early posttraumatic pelvic-osteomyelitis. In particular, due to the severity of the initial injury and the complex interdisciplinary approach, early diagnosis of the osteomyelitis is essential


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIII | Pages 168 - 168
1 May 2012
Appleyard R Donnellan M Sears W
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Existing techniques of posterior multi-point C1/2 stabilisation are technically demanding and can be hazardous. The coauthors have recently reported successful atlantoaxial fusion using a novel C1/2 stabilisation technique employing C1 multi-axial posterior arch screws (MA-PAS) in a clinical series of three patients where anatomical anomalies precluded established techniques. The technically less demanding nature of this new technique, and possible wider application in patients with normal anatomy, led the authors to investigate its biomechanical stability compared to other established techniques. Twenty-four human fresh-frozen cadaveric spines were harvested C0-C5. Motion was restricted to between C0 and C4. Each spine was non-destructively tested in flexion/extension, lateral bending and axial rotation, firstly in the intact state and then after Type 2 odontoid fracture destabilisation and insertion of Magerl-Gallie, Unicortical Harms, Bicortical Harms or MA-PAS instrumentation. ROM between C1 and C2 was monitored using two digital cameras. Results for each technique were compared statistically compared using ANOVA. The C1-C2 joint of the intact spines demonstrated high flexibility in flexion/extension (16.5deg). After instrumentation all specimens showed significantly reduced ROM in flexion/extension (Magerl-Gallie FE = 4.2deg, Unicort Harms FE = 7.2deg, Bicort Harms FE = 4.4deg). Lateral bend ROM of instrumented specimens (Magerl-Gallie LB =3.8deg, Unicort Harms LB = 3.8deg, Bicort Harms LB =2.3 deg) was, however, similar or slightly greater than intact (2.7 deg) . MA-PAS showed similar ROM in flexion/extension (4.2 deg) as the Magerl-Gallie and Harms techniques but was slightly higher in lateral bend (5.3 deg). The MA-PAS technique was shown to have similar biomechanical stability to the Magerl-Gallie and Harms techniques. Given the demonstrated biomechanical stability of the MA-PAS technique, it may be a suitable alternative to the existing technically demanding, and possibly more hazardous, multi-point fixation techniques in patients with normal, as well as anomalous, C1/2 segmental anatomy


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_16 | Pages 50 - 50
1 Oct 2014
Vetter S Mühlhäuser I Recum JV Grützner P Franke J
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Background. The distal part of the radius is the most common localisation of fractures of the human body. Dislocated intraarticular fractures of the distal radius (FDR) are frequently treated by open reduction and internal fixation with a volar locking plate (VLP) under fluoroscopic guidance. Typically the locking screws are placed subchondral near the joint line to achieve maximum stability of the osteosynthesis. To avoid intraarticular screw placement an intraoperative virtual implant planning system (VIPS) as an application for mobile C-arms was established. The aim of the study was the validation of the implemented VIPS comparing the intraoperative planning with the actual placement of the screws. The study was conducted as a single-centre randomised controlled trial in a primary care institution. The hypothesis of the study was that there is conformity between the virtual implant position and the real implant placement. Patients/Material and Methods. 30 patients with FDR type A3, C1 and C2 according to the AO-classification were randomised in two treatment groups and allocated either in the conventional or in the VIPS group in which the patients underwent an intraoperative planning before screw placement. The randomisation was performed on the basis of a computer-generated code. After fracture reduction an initial diaphyseal fixation of the plate was done. Then the matching of the three-dimensional virtual plate with the image of the real plate in the fluoroscopy shots in two planes was performed automatically. The implant placement was planned intraoperatively in terms of orientation, angulation and length of the screws. After the placement of four or five locking screws the implant position was verified with an intraoperative three-dimensional mobile C-arm scan. The locking screws near the joint line were examined and compared in relation to the actual and the planned inclination angle, the azimuth angle which is determined analogue to a compass rose and the screw-tip distance. The planned and actual parameters of the locking screws were then statistically analysed applying the Shapiro-Wilk - and the Students t-test. Results. 15 patients with FDR were treated in the VIPS arm. In the VIPS group six fractures type A3 one type C1 and eight type C2 were included. The control group showed a similar fracture distribution with six type A3 and nine type C2 fractures. The discrepancy between the actual and the planned screw-tip distance was 2,24 ± 0,97 mm and did not differ significantly (p>0,05). The angle of the planned and actual screw placement also did not vary significantly (p>0,05). The difference of the actual to the planned azimut angle accounted for 18,69°± 29,84. The planned and real inclination of the screws differed by 1,66° ± 4,46. Conclusion. The analysis shows that the screws were almost placed as planned. Differences between actual and planned placement of the screws were observed but were not statistically significant. Therefore the hypothesis of the study can be accepted. We assume, that the precise planning of the screw placement in FDR with VIPS can be transported into the surgical treatment


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_28 | Pages 76 - 76
1 Aug 2013
Franke J Vetter S Mühlhäuser I Grützner P von Recum J
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Background. Digital planning of implants in regard to position and size is done preoperatively in most cases. Intraoperative it can only be made by navigation systems. With the development of the VIPS-method (Virtual Implant Planning System) as an application for mobile C-arms, it is possible to do an intraoperative virtual planning of the screws near the joint in treatment of distal radius fractures by plating. Screw misplacement is a well known complication in the operative treatment of these fractures. The aim of this prospective randomised trial was to gain first clinical experiences and to compare VIPS with the conventional technique. The study hypothesis was that there will be less screw misplacement in the VIPS group. Methods. We included 40 patients with distal radius fractures type A3, C1 and C2 according to the AO-classification. In a pilot study the first 10 Patients were treated by the VIPS method to gain experience with VIPS in a clinical set-up. The results of the pilot-study are not part of this analysis. Then 15 Patients were web-based randomised into two groups. After diaphysial fixation of a 2.4 mm Variable Angle Two-Column Volar Distal Radius Plate and fracture reduction matching of a three-dimensional virtual plate to the two-dimensional image of the plate in the fluoroscopy shots in two plains was performed automatically in the VIPS group. The variable angle locking screws were planed in means of direction and length. Drilling was done by the use of the Universal Variable Angle Locking Drill Guide that was modified by laser marks at the rim of the cone to transfer the virtual planning. The drill guide enables drilling in a cone of 30°. In the control group the same implant was used in a conventional technique that means screw placement by the surgeon without digital planning. After implant placement an intraoperative three-dimensional scan was performed to check the position and length of the screws near the joint. OR- and fluoroscopy-time was documented. In addition the changes of misplaced screws were engaged. Results. In the VIPS group six A3-fractures, one C1-fracture and eight C2-fractures were included. In the control group six A3-fractures and nine C2-fractures were included. The intraoperative fluoroscopy time was 2.53 min (SD 1.44, range 1.27–7.14) in the VIPS group and 2.26 min (SD 0.51, range 1.55–3.39) in the control group (p=0.40). The OR-time was 53.33 min (SD 34.49, range 34–171) in the VIPS group and 42.27 min (SD 8.76, range 20–58) in the control group (p=0.23). In the VIPS group we changed three screws (two were too long, one was borderline near the joint) and two screws in the control group (one was too long, one was borderline near the joint) (p=0.24). Conclusions. The Virtual Implant Planning System is a reliable method that can be integrated easily in the workflow in treatment of distal radius fractures. There is a tendency that the virtual implant planning needs additional time, but there are no significant differences between the two groups. Further development is necessary to make the VIPS method beneficial


The Bone & Joint Journal
Vol. 102-B, Issue 11 | Pages 1587 - 1596
1 Nov 2020
Hotchen AJ Dudareva M Corrigan RA Ferguson JY McNally MA

Aims

This study presents patient-reported quality of life (QoL) over the first year following surgical debridement of long bone osteomyelitis. It assesses the bone involvement, antimicrobial options, coverage of soft tissues, and host status (BACH) classification as a prognostic tool and its ability to stratify cases into ‘uncomplicated’ or ‘complex’.

Methods

Patients with long-bone osteomyelitis were identified prospectively between June 2010 and October 2015. All patients underwent surgical debridement in a single-staged procedure at a specialist bone infection unit. Self-reported QoL was assessed prospectively using the three-level EuroQol five-dimension questionnaire (EQ-5D-3L) index score and visual analogue scale (EQ-VAS) at five postoperative time-points (baseline, 14 days, 42 days, 120 days, and 365 days). BACH classification was applied retrospectively by two clinicians blinded to outcome.