Our aim was to compare polylevolactic acid screws with titanium screws when used for fixation of the distal tibiofibular syndesmosis at mid-term follow-up. A total of 168 patients, with a mean age of 38.5 years (18 to 72) who were randomly allocated to receive either polylevolactic acid (n = 86) or metallic (n = 82) screws were included. The Baird scoring system was used to assess the overall satisfaction and functional recovery post-operatively. The demographic details and characteristics of the injury were similar in the two groups. The mean follow-up was 55.8 months (48 to 66). The Baird scores were similar in the two groups at the final follow-up. Patients in the polylevolactic acid group had a greater mean dorsiflexion (p = 0.011) and plantar-flexion of the injured ankles (p < 0.001). In the same group, 18 patients had a mild and eight patients had a moderate foreign body reaction. In the metallic groups eight had mild and none had a moderate foreign body reaction (p <  0.001). In total, three patients in the polylevolactic acid group and none in the metallic group had heterotopic ossification (p = 0.246). We conclude that both screws provide adequate fixation and functional recovery, but polylevolactic acid screws are associated with a higher incidence of foreign body reactions. Cite this article: Bone Joint J 2014;96-B:548–54

Due to increased life expectancy of human population, the amount of total knee replacements (TKR) is expected to increase. TKR reached a high grade of quality and safety, but most often it fail because of aseptic implant loosening caused by polyethylene (PE) wear debris. Wear is generated at the articulating surfaces, e.g. caused by three body particles, like bone fragments or bone cement particles. The aim of this experimental study was to compare the wear of tibial PE inserts combined with metallic and ceramic femoral components at three body wear situation induced by polymethylmethacrylate (PMMA) and zirconia (ZrO2) particles from the bone cement. Wear testing was performed for 5 Mio load cycles, using tibial standard PE inserts combined with the same CR femoral component, in two different materials, Cobalt Chromium (CoCrMo) and Biolox delta ® ceramic (Multigen Plus Knee System, Lima Corporate, Italy). A knee wear simulator, according to ISO 14243 (EndoLab GmbH, Rosenheim, Germany), was used to carry out the tests. The tests were performed in temperature-controlled test chambers at 37 °C, containing calf serum with a protein content of 30 g/l. Polymethylmethacrylate (PMMA) and zirconia (ZrO2) bone cement particles (Palacos R ®) were manufactured to a size of 30 μm. The three body particles were added at all stations onto the articulating surface of the tibial PE insert (7mg per condyle) at every 500,000 cycles. Wear was determined gravimetrically and the surfaces of tibial inserts were analysed by scanning electron microscope (SEM) after finishing the 5 million cycles. Furthermore, roughness of the PE insert surfaces and the articulating surfaces of the different femoral components were detected and the PE wear particles were analysed by SEM. The average gravimetrical wear rates of the tibial PE inserts in combination with CoCr and Biolox delta ® ceramic femoral components amounted to 6.4 ± 0.9 mg and 2.6 ± 0.4 mg per million cycles, respectively. Beside bone cement particles on the articulating surface of the PE inserts, polished surfaces and scratches were detected by SEM. In comparison to the untreated surfaces of the PE inserts at both material pairings the surface roughness at the articulating areas showed deep scratches and polished regions. Analyses of the metallic femoral components showed scratches at the articulating surfaces, none on ceramics. The present study pointed out the effect of femoral component material in an abrasive three body wear situation on the wear properties of TKR. The wear simulator tests showed that wear of PE inserts under three body wear conditions, in combination with ceramic femoral components, was significantly lower than with metallic femoral components. With regard to anti-allergic properties, ceramic femoral components are promising products for TKR

INTRODUCTION. A detailed clinical examination and investigations are required to evaluate the cause of persisting groin pain following a metal on metal (MoM) hip replacement. Adverse reaction to metallic debris (ARMD) is an emerging problem with MoM hip replacements. It is an umbrella term encompassing metallosis, pseudo-tumors and aseptic lymphocytic vasculitis associated lesions (ALVAL). The role of imaging in the diagnosis of this complex problem is still unclear. A study was undertaken to evaluate the efficacy of ultrasound in diagnosis of ARMD following a MoM hip replacement. METHODS. The study group included 35 patients with a clinical and histological diagnosis of ARMD, who had a preoperative ultrasound. All ultrasound procedures were performed on the anterior and lateral aspects of the painful hip with a high frequency probe of 9–13 MHz (Sonoline Antares – Siemens). RESULTS. All patients diagnosed with ARMD had abnormalities identified on ultrasound. Fluid inside the joint was noted in 30 out of 35 procedures (85.7 %). Fluid outside the joint was noted in 33 procedures (94.3 %). Amongst the patients with fluid outside the joint, 32 had iliopsoas and 30 had trochanteric bursitis. Echogenic reflections were noted in 31 out of 35 procedures (88.6 %). Considerable attenuation or absence of iliopsoas and gluteus tendon reflection was seen in many patients with echogenic fluid collections on the anterior and trochanteric aspects of hip. Progression of such changes was noted on further 5 patients, who had a repeat ultrasound within an interval of 3–6 months. 1 patient had a progression from anechogenic to echogenic joint effusion. DISCUSSION. Different radiological investigations including MRI scan have been used for evaluation of painful MoM hip arthroplasty. To our knowledge, this is the first study to demonstrate the efficacy of ultrasound in diagnosis of ARMD. Floating echogenic reflections and fluid collections around iliopsoas and gluteus medius/minimus tendons is highly suggestive of ARMD. Ultrasound is a cheap, non-invasive and dynamic investigation and has been shown to be reliable in diagnosis of ARMD

Single focal grade IV cartilage lesion in the knee has a poor healing capacity. Instead these lesions often progress to severe and generalized osteoarthritis that may result in total knee replacement. Current treatment modalities aim at biological repair and, although theoretically appealing, the newly formed tissue is at the best cartilage-like, often fibrous or fibrocartilaginous. This at the expense of sophisticated laboratory resources, delicate surgery and strict compliance from patients.

An alternative may be small implants of biomaterial inserted to replace the damaged cartilage. We investigated the response of the opposing tibia cartilage to a metallic implant inserted at different depth into the surrounding cartilage level.

The evidence for treatment of acute complex radial head fractures with radial head replacement (RHR) predominantly comprises short to mid-term follow-up. This study describes the complications and long-term patient reported outcomes following RHR. From a single-centre trauma database we retrospectively identified 119 patients over a 16-year period who underwent primary RHR for an acute complex radial head fracture. We reviewed electronic records to document post-operative complications, including prosthesis revision and removal. Patients were contacted to confirm complications and long-term patient reported outcomes. The primary outcome measure was the QuickDash (QD). The mean age at injury was 50 years (16–94) and 63 (53%) were female. Most implants were uncemented ‘loose-fit’ monopolar prostheses; 86% (n=102) were metallic and 14% (n=17) silastic. Thirty patients (25%) required revision surgery (n=3) or prosthesis removal (n=27). Five patients underwent arthrolysis and there were four cases of infection. In the long-term, 80% (80/100; 19 deceased) were contacted at a mean of 12 years (7.5–23.5). The median QD was 6.8 (IQR, 16.8), the median EQ-5D was 0.8 (IQR, 0.6) and the median Oxford Elbow Score was 46 (IQR, 7). Overall satisfaction was high with a mean of 9.4/10 (2–10). There was no significant difference in any outcome measure for those patients requiring revision or removal surgery (all p>0.05). This is the largest series in the literature documenting the long-term patient reported outcome after RHR. Despite a quarter of patients requiring further surgery, RHR is supported by positive long-term results for the treatment of complex radial head fractures

The aim of this study was to report the outcome of radial head replacement for complex fractures of the radial head, and determine any risk factors for prosthesis removal or revision. We identified 119 patients who were managed acutely using primary radial head replacement for an unstable fracture of the radial head over a 15-year period. Demographic data, fracture classification, management, complications and subsequent surgeries were recorded following retrospective clinical record review. There were 105 (88%) patients with a mean age of 50 yrs (16–93) and 54% (n=57) were female. There were 95 (91%) radial head fractures and 96% were a Mason type 3 or 4 injury. There were 98 associated injuries in 70 patients (67%), with an associated coronoid fracture (n=29, 28%) most frequent. All implants were uncemented monopolar prostheses, with 86% metallic and 14% silastic. At a mean short-term follow-up of 1 year (range, 0.1–5.5; n=87) the mean Broberg and Morrey score was 80 (range, 40–99), with 49.5% achieving an excellent or good outcome. At a final mean review of 6.7 yrs (1.8–17.8), 29 (27%) patients had undergone revision (n=3) or removal (n=26) of the prosthesis. Independent risk factors of prosthesis removal or revision were silastic implant type (p=0.010) and younger age (p=0.015). This is the largest series in the literature documenting the outcome following radial head replacement for complex fractures of the radial head. We have demonstrated a high rate of removal or revision for all implants, with younger patients and silastic implants independent risk factors

Introduction. The current investigation includes a retrospective review of the experience of five Institutions with distal femur megaprostheses for tumor over a twenty year period, to analyze the incidence and etiology of failure, using a new classification system based upon the failure modes. Methods. Between 1974 and 2008, 2174 patients underwent primary limb preservation for a benign or malignant extremity tumor using a metallic megaprosthesis at five Institutions, 951 (43.7%) were distal femur replacements. Retrospective analysis of complications according to the Letson and Ruggieri Classification was performed and Kaplan-Meier curves of implant survival were defined. Segmental megaprosthetic reconstruction failures were categorized as mechanical and non-mechanical failures. Results. A total of 951 skeletally mature patients received a segmental endoprosthesis for the treatment of an oncologic condition. Overall 261 (27%) of the primary procedures were considered failures. There were 137 mechanical failures (14.4%): 12 (1.3%) Type 1 (soft tissue failure), 65 (6.8%) Type 2 (aseptic loosening), and 60 (6.3%) Type 3 (structural failure). Non-mechanical causes accounted for 124 failures (13%): 45 (4.7%)Type 4 (tumor progression) and 79 (8.3%) Type 5 (infection). The overall implant survival to all modes of failure was 77% at 10 years and 73% at 20 years. The implant survival to aseptic loosening was over 90% at 10 years. Conclusion. Most frequent cause of failure was infection followed by aseptic loosening and structural failure. The implant survival at long term was quite satisfactory

Introduction. The action of the radial head in the stability of the elbow is currently admitted. Its conservation is not always possible in complex fractures. The association with a posterolateral dislocation of the elbow leads to a higher risk of instability of the elbow joint and also at a longer term to degenerative changes. Some authors recommend the use of metallic radial head implant, acting as a spacer. The results seems encouraging but should the resection arthroplasty associated with the repair of the medial collateral ligament be abandoned?. Material and methods. In an amount of 35 consecutive patients who were taken in charge for an elbow dislocation 26 were included in this retrospective study, 13 of them had the association of a dislocation and a fracture of the radial head. In all 13 cases the radial head was considered as inadequate with a conservative treatment and was resected. The patients were assessed clinically according to the American Shoulder and Elbow Surgeons score (ASES) and the Mayo elbow performance index with a mean follow-up of 13 years (ranging from 5 to 15). The degenerative changes were assessed on plan × rays and an additional axial view according to the 4 stages described by Morrey. Results. No redislocation occurred. According to the Broberg/Morrey index 92% of the patients were considered as having a good result. They returned to work with no hindering. Signs of osteoarthritis grade 1 or 2 were observed and were clinically well tolerated. There was no difference for this item between the patients who conserved their radial head and those who sustained a resection. All patients were satisfied although they were protecting their joint against overuse while working. Discussion. The studies about the use of prosthesis of the radial head offer similar functional results. Degenerative changes on the trochleo ulnar joint are identical in all type of treatment. In order to prevent stiffness in the elbow joint an early post operative rehabilitation is recommended, it justifies a surgical stabilization associated with the use of an adapted dynamic splint. Conclusion. In case of elbow dislocation with a fracture of the radial head when its preservation is impossible, the resection without any prosthetic replacement remains a reasonable option if associated with a repair of the medial collateral ligament. At long term the functional results are still good with mild signs of osteoarthritis eliminating ipso facto the problem of an implant survivorship

Introduction. In knee arthroplasty a ceramic component has several advantages: first, there is no ion release implying a risk for potential allergies. Second, the hardness of the material leads to a scratch resistance which ultimately reduces PE wear over time. In the past, ceramic components in knee applications were limited in the variety of design possibilities due to necessary thickness of the component resulting from the associated fracture risk of ceramics. By the development of an alumina matrix composite material with increased mechanical properties it is possible to develop ceramic knee components which have nearly the same design as a metal component and use the same implantation technique as well as the same instruments. This offers the surgeon the opportunity to choose intraoperatively between metal or ceramic knee components. Extensive in-vitro testing shows that ceramic knee components achieve superior mechanical test results. The reliability of the components is proven by two different burst tests and a fatigue test for both a femoral and a tibial ceramic knee component. Material and method. The mechanical proof-test was developed by subsequent steps of numerical load/stress analysis and design of an adequate mechanical test equipment. The procedure was organized as follows:. Oncologic: Analysis of relevant maximum in-vivo loading conditions. Analysis of the “boundary conditions”. Finite Element analysis: Identifying regions of highest stress concentration. Design analysis and accommodation if necessary. Development of an adequate mechanical test equipment which produces stresses comparable to the in-vivo conditions. Performing mechanical tests with ceramic femoral components. Validation of the test concept: comparison of test results and stress analysis. Assign “safety margin”,. Establish “proof test”. Results. Two independent load scenarios have been determined for each type of components as being in-vivo relevant. Hence, the developed proof-test consists of two subsequent load tests, the so-called regular test and the tension test for the femoral components, and the upper side test and the lower side test for the tibial components. In the regular test, the mechanical strength of the polished outer condyles is tested using a force which is equivalent to an in-vivo loading of 16 times bodyweight. In the tension test, the interior sides of the condyles are stressed in the sagittal plane ensuring a mechanically reliable implantation. This test is performed with a force equivalent to 10 times bodyweight. Discussion. The procedure to determine the proof loads using the maximum in-vivo loads together with a safety factor ensures the mechanical safety of the ceramic knee component. Together with the well-known excellent wear and biological behaviour of ceramics, this application provides an alternative to common metallic knee components. Clinical observations in the framework of a multi-centre study in different European countries have been started and show very promising results

Introduction. Application of an external fixator for type B and C pelvic fractures can be life saving. Anteriorly the fixator half pins can be placed in the long and thick corridor of bone in the supra-acetabular region often referred to as the low anterior ex-fix. Pins in this location are favoured as they are more stable biomechanically. The bone tunnel for the low anterior ex-fix can be visualised with an iliac oblique projection intra-operatively. In some cases despite being outside the articular surface it may still be low enough to pass through the capsular attachment of the hip joint on the anterior inferior iliac spine. We aim to provide radiological markers for the most superior fibres of the capsule to help accurate extra-capsular pin placement within the supra-acetabular bone tunnel. Materials and Methods. Thirteen cadaveric pelves, embalmed with the method of Thiel, were used for this study. An image intensifier was positioned to acquire an iliac oblique outlet view, such that the supra acetabular bone tunnel was visualised. This was achieved by positioning the beam 30 degrees cephalad and 20 degrees medial. Both left and right hemipelves were examined in this way. A standard size metallic disc was included in all images with in the acetabulum to allow for image calibration. The proximal most fibres of the hip joint capsule were marked with a K-wire so that their relation to the bone tunnel could be clearly seen on the images. Once all images were acquired they were calibrated and analysed using ImageJ Software to estimate the height and maximum width of the bone tunnel as seen on the images and the vertical distance of the superior most fibres of the capsule from the dome of the acetabulum. Results. The mean height of the bone tunnel was 24.9 mm (SD 4.3 mm, Range 18.9–33.2 mm) and the maximum width of the tunnel was 11.7 mm (SD 2.6 mm, Range 7.6–16.3 mm). The inferior margin of the bone tunnel was on average 7.4 mm (SD 3.4 mm, Range 1.1–14.4 mm) superior to the acetabular dome and the most proximal fibres of the capsule were on average 9.2 mm (SD 2.4 mm, Range 4.7–16.1 mm) superior to the acetabular dome. This meant that on average 3.6 mm (SD 2.1 mm, Range 0.3–8.9 mm) of the inferior portion of the tunnel is within the joint. There was no statistically significant difference between the left and right sides. Conclusion. There is adequate space for two long external fixator pins within the described tunnel. These should be placed in the upper half of the anterior inferior iliac spine. Below this level there is risk of being intra-capsular which can lead to septic arthritis. For this reason we recommend that supra-acetabular pins should be placed at least 16 mm superior to the acetabular dome as visualised on the iliac oblique outlet view

Aims

This study reviews the use of a titanium mesh cage (TMC) as an adjunct to intramedullary nail or plate reconstruction of an extra-articular segmental long bone defect.

We describe 261 peripheral nerve injuries sustained in war by 100 consecutive service men and women injured in Iraq and Afghanistan. Their mean age was 26.5 years (18.1 to 42.6), the median interval between injury and first review was 4.2 months (mean 8.4 months (0.36 to 48.49)) and median follow-up was 28.4 months (mean 20.5 months (1.3 to 64.2)). The nerve lesions were predominantly focal prolonged conduction block/neurapraxia in 116 (45%), axonotmesis in 92 (35%) and neurotmesis in 53 (20%) and were evenly distributed between the upper and the lower limbs. Explosions accounted for 164 (63%): 213 (82%) nerve injuries were associated with open wounds. Two or more main nerves were injured in 70 patients. The ulnar, common peroneal and tibial nerves were most commonly injured. In 69 patients there was a vascular injury, fracture, or both at the level of the nerve lesion. Major tissue loss was present in 50 patients: amputation of at least one limb was needed in 18. A total of 36 patients continued in severe neuropathic pain.

This paper outlines the methods used in the assessment of these injuries and provides information about the depth and distribution of the nerve lesions, their associated injuries and neuropathic pain syndromes.

Filling the empty holes in peri-articular locking plates may improve the fatigue strength of the fixation. The purpose of this in vitro study was to investigate the effect of plugging the unused holes on the fatigue life of peri-articular distal femoral plates used to fix a comminuted supracondylar fracture model.

A locking/compression plate was applied to 33 synthetic femurs and then a 6 cm metaphyseal defect was created (AO Type 33-A3). The specimens were then divided into three groups: unplugged, plugged with locking screw only and fully plugged holes. They were then tested using a stepwise or run-out fatigue protocol, each applying cyclic physiological multiaxial loads.

All specimens in the stepwise group failed at the 770 N load level. The mean number of cycles to failure for the stepwise specimen was 25 500 cycles (sd 1500), 28 800 cycles (sd 6300), and 26 400 cycles (sd 2300) cycles for the unplugged, screw only and fully plugged configurations, respectively (p = 0.16). The mean number of cycles to failure for the run-out specimens was 42 800 cycles (sd 10 700), 36 000 cycles (sd 7200), and 36 600 cycles (sd 10 000) for the unplugged, screw only and fully plugged configurations, respectively (p = 0.50). There were also no differences in axial or torsional stiffness between the constructs. The failures were through the screw holes at the level of comminution.

In conclusion, filling the empty combination locking/compression holes in peri-articular distal femur locking plates at the level of supracondylar comminution does not increase the fatigue life of the fixation in a comminuted supracondylar femoral fracture model (AO 33-A3) with a 6 cm gap.