Aims. Musculoskeletal infection is a devastating complication in both trauma and elective orthopaedic surgeries that can result in significant morbidity. Aim of this study was to assess the effectiveness and complications of local antibiotic impregnated dissolvable synthetic calcium sulphate beads (Stimulan Rapid Cure) in the hands of different surgeons from multiple centres in surgically managed bone and joint infections. Methods. Between January 2019 and December 2022, 106 patients with bone and joint infections were treated by five surgeons in five hospitals. Surgical debridement and calcium sulphate bead insertion was performed for local elution of antibiotics in high concentration. In all, 100 patients were available for follow-up at regular intervals. Choice of antibiotic was tailor made for each patient in consultation with microbiologist based on the organism grown on culture and the sensitivity. In majority of our cases, we used a combination of vancomycin and culture sensitive heat stable antibiotic after a thorough debridement of the site. Primary wound closure was achieved in 99 patients and a split skin graft closure was done in one patient. Mean follow-up was 20 months (12 to 30). Results. Overall, six out of 106 patients (5.6%) presented with sepsis and poorly controlled comorbid conditions, and died in the hospital within few days of index surgery. Out of the remaining 100 patients, control of infection was achieved in 95 patients (95%). Persistence of infection was noted in five (5%) patients. Out of these 95 patients that had good control of infection, four patients (4.2%) with gap nonunion needed Masquelet procedure to achieve union. Conclusion. Our multicentre experience confirmed that surgical debridement along with calcium sulphate bead insertion was effective in treating bone and joint infections without any side effects and complications. Cite this article: Bone Jt Open 2023;4(7):516–522

Technological advancements in orthopaedic surgery have mainly focused on increasing precision during the operation however, there have been few developments in post-operative physiotherapy. We have developed a computer vision program using machine learning that can virtually measure the range of movement of a joint to track progress after surgery. This data can be used by physiotherapists to change patients’ exercise regimes with more objectively and help patients visualise the progress that they have made. In this study, we tested our program's reliability and validity to find a benchmark for future use on patients. We compared 150 shoulder joint angles, measured using a goniometer, and those calculated by our program called ArmTracking in a group of 10 participants (5 males and 5 females). Reliability was tested using adjusted R squared and validity was tested using 95% limits of agreement. Our clinically acceptable limit of agreement was ± 10° for ArmTracking to be used interchangeably with goniometry. ArmTracking showed excellent overall reliability of 97.1% when all shoulder movements were combined but there were lower scores for some movements like shoulder extension at 75.8%. There was moderate validity shown when all shoulder movements were combined at 9.6° overestimation and 18.3° underestimation. Computer vision programs have a great potential to be used in telerehabilitation to collect useful information as patients carry out prescribed exercises at home. However, they need to be trained well for precise joint detections to reduce the range of errors in readings

We aimed to determine the rate of and risk factors for post-traumatic osteoarthritis (PTOA) and total knee arthroplasty (TKA) requirement after operative management of tibial plateau fractures (TPF) in older adults. We conducted a retrospective cohort study of 182 operatively managed TPFs in 180 patients ≥60 years old over a 12-year period with minimum follow up 1 year. Data including patient demographics, clinical frailty scores, mechanism of injury, management, reoperation and mortality were recorded. Radiographs were reviewed for: Schatzker classification; pre-existing knee osteoarthritis (KOA); severe joint depression >15mm; and development of PTOA. Kaplan Meier survival analysis was performed. Regression analysis was used to identify risk factors for radiographic indication for TKA and actual TKA. Forty-seven percent were Schatzker II fractures. Radiographic KOA was present at fracture in 32.6%. Fracture fixation was performed in 95.6% cases and acute TKA in 4.4%. Thirteen patients underwent late TKA (7.5%). At five-years, 11.8% (6.0-16.7 95% CI) had required TKA and 20.9% (14.4-27.4 95% CI) had a radiographic indication for TKA. Severe joint depression and pre-existing KOA were associated with worse survival for endpoints radiographic indication for TKA and actual TKA. Severe joint depression (HR 2.49(1.35-4.61 95% CI), p=0.004), pre-existing KOA (HR 2.23(1.17-4.23), p=0.015) and inflammatory arthropathy (HR 2.4(1.04-5.53), p=0.039) were independently associated with radiographic indication for TKA. In conclusion, severe joint depression and pre-existing arthritis are independent risk factors for both severe PTOA and TKA after TPFs in older adults. These features should be considered as an indication for primary management with acute TKA

Gram staining is used as an initial indicator of synovial joint infection but has widely varied false negative rates in the literature. Clinical decisions are often made on the basis of gram stain results, such as whether a patient requires urgent surgery, and therefore it is important to understand the tests efficacy. A retrospective review of synovial fluid aspirates in NHS Tayside for the years 2017 and 2018 was performed from the departmental microbiology database. Aspirates of large joints were included (hip, knee, shoulder, wrist, elbow, ankle). Any joints with prosthesis were excluded, including fixation metalwork. Any abscess overlying a joint that was not proven to penetrate the joint was also excluded. Initial gram stain results and formal culture results were reviewed. Final culture results were considered to be the gold standard to compare gram stain results to. 2167 samples were reviewed. Of these 1552 were excluded base on inclusion criteria. Of the remaining 615, 120 (19.5%) were culture positive. There were 33 positive gram stain results, 1 false positive and 32 true positive results. The sensitivity was 26.67% with a specificity of 99.80% (p=0.0001). The negative predictive value is 84.88% (CI 83.44% – 86.21%). These results show that gram stain tests of native joints have a low sensitivity and poor negative predictive value. This is reflected in the current literature with prosthetic joints. Based on this study caution should be used when interpreting a negative gram stain result with appropriate safety netting and follow up required alongside clinical assessment

Arthrodesis of the first metatarsophalangeal joint (MTPJ) is the most reliable surgical option, for hallux rigidus from end-stage osteoarthritis. The aim of the study was to compare the functional outcomes of memory nickel-titanium staples versus a compression plate with a cross screw construct for first MTPJ arthrodesis using the Manchester–Oxford Foot Questionnaire (MOXFQ).

Patients who underwent MTPJ arthrodesis using either memory nickel-titanium staples or a compression plate with a cross screw construct were identified from the surgical lists of two orthopaedic consultants. Pre and post-operative MOXFQ questionnaire, a validated patient-reported outcome measure, was administered, and responses were analysed to derive the MOXFQ summary index.

The study included 38 patients (staple group N=12 and plate and cross screw group N=26). 23 patients were female and 15 were male. Mean age was 64.8 years (SD 9.02; 40 to 82). Initial analysis showed no significant difference in preoperative MOXFQ scores between the groups (p = 0.04). Postoperatively, the staple group exhibited a mean improvement of 36.17, surpassing the plate group's mean improvement of 23. Paired t-test analysis revealed a statistically significant difference (t-score= 2.5, p = 0.008), favouring the use of staples.

The findings indicate that the use of staples in MTPJ arthrodesis resulted in a significantly greater improvement in MOXFQ scores compared to plates. Further research is needed to explore the underlying factors contributing to this difference and to evaluate long-term effects on patient outcomes.

Introduction. Muscle stiffness and joint contractures are common complications of limb lengthening. Authors have demonstrated less permanent soft tissue complications with intramedullary lengthening than external fixation. Our aim was to evaluate the joint response following intramedullary femoral lengthening and need for physiotherapy and alteration to rate/rhythm of lengthening. Method. A retrospective review of documentation for all femoral Precice nails in our centre inserted between 2012 and 2017. This involved 98 nails (68 antegrade, 30 retrograde) in 88 patients (59 males, 29 females) with a mean age of 32 years (range 12–69 yrs). We excluded cases where there was no documentation regarding Range of Movement (ROM). Bilateral lengthenings were recorded as separate cases. This left 50 antegrade, 16 retrograde cases with hip ROM data and 55 antegrade, 26 retrograde cases with Knee ROM data. Results. Hip. In the antegrade group 20 cases (39%) developed no stiffness throughout treatment. ROM decreased in 61% (n=30) of cases and the median length at which this occurred was 3cm. Where a retrograde nail was inserted 62.5% of cases (n=10) maintained normal range of motion. The median length at which ROM decreased was 3.25cm, this occurred in 6 cases (37.5%). . Knee. Where the antegrade nail was inserted, 22 cases (40%) did not develop stiffness. There was reduced ROM in 33 cases (60%), occurring at a median distance of 2cm. The median distance at which reduced ROM occurred with the retrograde nails was 1.5cm, this occurred in 23 cases (88.5%). 3 cases did not develop stiffness. All cases regained full ROM. Conclusion. Although there was no permanent loss, Joint Stiffness still occurs with intramedullary limb lengthening and there remains the need for regular physiotherapy. There are no data from other institutions for comparison. Rehabilitation guidelines and a proforma to accurately monitor patients ROM throughout treatment have been developed

Proliferation of synovial Mesenchymal Stromal/Stem Cells (MSCs) leads to synovial hyperplasia (SH) following Joint Surface Injury (JSI). Uncontrolled Yap activity causes tissue overgrowth due to modulation of MSC proliferation. We hypothesised that YAP plays a role in SH following JSI. A spatiotemporal analysis of Yap expression was performed using the JSI model in C57Bl/6 mice. Synovial samples from patients were similarly analysed. Gdf5-Cre;Yap1fl/fl;Tom mice were created to determine the effect YAP1 knockout in Gdf5 lineage cells on SH after JSI. In patients, Yap expression was upregulated in activated synovium, including a subset of CD55 positive fibroblast-like synoviocytes in the synovial lining (SL). Cells staining positive for the proliferation marker Ki67 expressed active YAP. In mice, Yap was highly expressed in injured knee joint synovium compared to controls. Yap mRNA levels at 2 (p<0.05) and 8 days (p<0.001) after injury were increased. Conditional Yap1 knockout in Gdf5 progeny cells prevented hyperplasia of synovial lining (SL) after JSI. Cellularity was significantly decreased in the SL but not in the sub-lining of injured Yap1 knockout- compared to control mice. The percentage of cells in synovium that were Tom+ increased in response to JSI in control and haplo-insufficient but not in YAP1 knockout mice (p<0.05). Modulation of YAP and proliferation of MSCs in the synovium after JSI provides a system to study the role of SH after trauma in re-establishing joint homeostasis and is a potential novel therapeutic target for the treatment of post traumatic OA

The objective of this study was to compare differences in alignment following robotic arm-assisted bi-unicompartmental knee arthroplasty (Bi-UKA) and conventional total knee arthroplasty (TKA). This was a prospective, randomised controlled trial of 70 patients. 39 TKAs were implanted manually, as per standard protocol at our institution, and 31 Bi-UKA patients simultaneously received fixed-bearing medial and lateral UKAs, implanted using robotic arm-assistance. Preoperative and 3-month postoperative CT scans were analysed to determine hip knee ankle angle (HKAA), medial distal femoral angle (MDFA), and medial proximal tibial angle (MPTA). Analysis was repeated for 10 patients by a second rater to validate measurement reliability by calculating the intra-class correlation coefficient (ICC). Mean change in HKAA towards neutral was 2.7° in TKA patients and 2.3° in Bi-UKA patients (P=0.6). Mean change in MDFA was 2.5° for TKA and 1.0° for Bi-UKA (P<0.01). Mean change in MPTA was 3.7° for TKA and 0.8° for Bi-UKA (P<0.01). Mean postoperative MDFA and MPTA for TKAs were 89.8° and 89.6° respectively, indicating orientation of femoral and tibial components perpendicular to the mechanical axis. Mean postoperative MDFA and MPTA for Bi-UKAs were 91.0° and 86.9° respectively, indicating a more oblique joint line orientation. Inter-rater agreement was excellent (ICC>0.99). Early functional activities, according to the new Knee Society Scoring System, favoured Bi-UKAs (P<0.05). Robotic arm-assisted, cruciate-sparing Bi-UKA better maintains the natural anatomy of the knee in the coronal plane and may therefore preserve normal joint kinematics, compared to a mechanically aligned TKA. This has been achieved without significantly altering overall HKAA

Crescent fracture dislocations are a well-recognised subset of pelvic ring injuries which result from a lateral compression force. They are characterised by disruption of the sacroiliac joint and extend proximally as a fracture of the posterior iliac wing. We describe a classification with three distinct types. Type I is characterised by a large crescent fragment and the dislocation comprises no more than one-third of the sacroiliac joint, which is typically inferior. Type II fractures are associated with an intermediate-size crescent fragment and the dislocation comprises between one- and two-thirds of the joint. Type III fractures are associated with a small crescent fragment where the dislocation comprises most, but not all of the joint. The principal goals of surgical intervention are the accurate and stable reduction of the sacroiliac joint. This classification proves useful in the selection of both the surgical approach and the reduction technique. A total of 16 patients were managed according to this classification and achieved good functional results approximately two years from the time of the index injury. Confounding factors compromise the summary short-form-36 and musculoskeletal functional assessment instrument scores, which is a well-recognised phenomenon when reporting the outcome of high-energy trauma

Aims. Our aim in this study was to describe the long-term survival of the native hip joint after open reduction and internal fixation of a displaced fracture of the acetabulum. We also present long-term clinical outcomes and risk factors associated with a poor outcome. Patients and Methods. A total of 285 patients underwent surgery for a displaced acetabular fracture between 1993 and 2005. For the survival analysis 253 were included, there were 197 men and 56 women with a mean age of 42 years (12 to 78). The mean follow-up of 11 years (1 to 20) was identified from our pelvic fracture registry. There were 99 elementary and 154 associated fracture types. For the long-term clinical follow-up, 192 patients with complete data were included. Their mean age was 40 years (13 to 78) with a mean follow-up of 12 years (5 to 20). Injury to the femoral head and acetabular impaction were assessed with CT scans and patients with an ipsilateral fracture of the femoral head were excluded. Results. A total of 36 patients underwent total hip arthroplasty (THA). The overall ten-year survival of the hip joint was 86% (95% confidence interval (CI) 81% to 90%) and the 20-year survival was 82% (95% CI 76% to 87%). Injury to the femoral head and acetabular impaction were the strongest predictors of failure, with the long-term survival rate falling towards 50% in these patients. The survival fell to 0% at three years when both these risk factors were present in patients aged > 60 years. Conclusion. The long-term survival of the native hip joint after acetabular fractures was good, but the presence of injury to the femoral head and acetabular impaction proved to be strong predictors of failure, especially in patients aged > 60 years. These patients may be better treated with a combination of open reduction and internal fixation and primary arthroplasty. Cite this article: Bone Joint J 2017;99-B:834–40

To validate the Modified Forgotten Joint Score (MFJS) as a new patient-reported outcome measure (PROM) in hip and knee arthroplasty (THR/TKR) against the UK's gold standard Oxford Hip and Knee Scores (OHS/OKS). The MFJS is a new assessment tool devised to provide a greater discriminatory power, particularly in well performing patients. It measures an appealing concept; the ability of a patient to forget about their artificial joint in everyday life. Postal questionnaires were sent out to 400 THR and TKR patients who were 1–2 years post-op. The data collected from the 212 returned questionnaires was analysed in relation to construct and content validity. 77 patients took part in a test-retest repeatability assessment. The MFJS proved to have an increased discriminatory power in high-performing patients in comparison to the OHS and OKS, highlighted by its more normal frequency of distribution and reduced ceiling effects. 30.8% of patients (n=131) achieved excellent OHS/OKS scores of 42–48 this compared to just 7.69% of patients who achieved a proportionately equivalent MFJS score of 87.5–100. The MFJS proved to have an increased test-retest repeatability based upon its intra-class correlation coefficient of 0.97 compared to the Oxford's 0.85. The MFJS provides a more sensitive tool in the assessment of well performing hip and knee arthroplasties in comparison to the OHS/OKS. The MFJS tests the concept of awareness of a prosthetic joint, rather than pain and function and therefore should be used as adjunct to the OKS/OHS

Purpose. To analyse the early results of unconstrained pyrocarbon joint replacements in patients with osteo-arthritis of the metacarpo-phalangeal joints. Background. Silicone arthroplasty, as introduced by Swanson in 1962 has remained the most popular procedure to treat arthritis of the metacarpo-phalangeal (MCP) joints. However, despite providing good pain relief, they have shown to demonstrate breakage rates up to 82% at 5 years. This is of great concern in the osteoarthritis (OA) patient group, who tend to be younger and have higher functional demands compared to their rheumatoid counterparts. The newer unconstrained pyrolytic carbon MCP joint prostheses may therefore be more suitable in OA patients whose soft tissue constraints are intact and whose hand function is strong. This study is the first to analyse the results of this implant in a cohort of OA patients only, with prospective data. Methods. 19 primary pyrocarbon metacarpo-phalangeal joint replacements, in 11 patients (5 men and 6 women) were reviewed, with prospective data collection. The diagnosis was primary osteoarthritis in all patients. The mean age at operation was 66.4 years (range 55–82 years). 2 patients underwent concomitant trapiezectomy and one underwent DIPJ fusion. All patients were right hand dominant −75% underwent surgery in their dominant hand. Eleven of the nineteen joints were performed in the index finger, with the remainder in the middle finger. Mean follow up is 22.1 months (range 11–37). Results. At the 3 month post-operative hand therapy assessment, the arc of motion had improved from a mean of 32 degrees to 45 degrees and flexion had improved from a mean of 51 degrees to 66 degrees. Grip strength improved from a mean 20 to 27Kg. DASH scores significantly improved from a mean of 40 to 10 (p=0.01). All patients were satisfied with their outcomes and would have the surgery again. Pre-operative radiographs demonstrated joint narrowing in all patients but no evidence of heterotopic ossification, cystic change or erosions. Post-operatively, there has been no radiographic evidence of joint dislocation, resorption stress-shielding, loosening, migration or heterotopic ossification. There were three intra-operative complications of phalangeal fractures that were immediately treated with a cerclage wire. In one patient there has been a fracture of the proximal phalangeal implant at 14 months which was asymptomatic. One patient has required revision for mal-rotation of the implant leading to loss of index finger supination. Conclusion. Our results demonstrate excellent early results of pyrocarbon MCP joint arthroplasty in OA patients

Periprosthetic osteolysis depends on the biological activity of wear particles, but there is little known about the distribution of polyethylene wear particles (PE) in the surrounding joint tissue. The purpose of this study was to examine the localisation of wear particles of six different PEs, including four crosslinked polyethylenes (XPE), as well as their biological activity in the murine knee. Material and Methods. Wear particles of 4 XPE- and 2 UHMWPE-inserts were isolated (knee joint simulator). For all groups the particles were similar in size and shape (mean diameter 0.3–05μm; 20nm-nucleopore-filter; ISO; n = 100.000).56 female Balb/c mice were randomly assigned to six treatment groups and one control group: control (PBS), XPE1 (3×30 kGy Gamma, annealed/sequential irradiated), XPE2 (95 kGy E-beam, remelted), XPE3 (65 kGy E-beam, remelted), XPE 4 (50 kGy Gamma, remelted), UHMWPE 1, UHMWPE 2. 50 μl of each particle suspension [(0.1% vol/vol (particle volume/PBS volume) after removal of endotoxin] were injected into the left knee joint. After 1 week the mice were killed and a histological and immunhistochemical analysis of the knee joints was done (IL-1, TNF-, ICAM-1). For the immunhistochemistry the articular cartilage, the bone marrow and the synovial membrane were evaluated semiquantitatively (Kruskal-Wallis test; all pairwise multiple comparison procedure; Bonferoni correction; significance level: p<0.05). Results. All groups showed a thickened synovial layer with an increased cellular infiltration. The particles of XPE 1 and 2 were localised in the bone marrow as well as in the joint space. In contrast, the particles of XPE 3 and 4 were distributed in the synovial layer and in the bone marrow as well, but not in the joint space. The UHMWPE1 particles were mainly located in the bone marrow and joint space while the UHMWPE2 particles were mainly found in the bone marrow and the synovial layer. For all PE groups there was a higher cytokine expression compaired to control (p<0.0024) without any differences between the groups (bone marrow/synovial layer). The chondrocytes in the groups with XPE 1- and XPE 2-particles expressed more TNF- than in the control group and the other treatment groups (p = 0.000). Conclusion. XPEs lead to a similar inflammatory reaction in vivo compared to conventional polyethylenes. The high TNF- expression in the articular cartilage (groups XPE 1 and 2) might be explained by the localisation of the wear particles in the joint space in direct contact with the chondrocytes. Long-term studies are necessary to analyse the effects of different wear particle distributions in the joint surrounding tissue after knee and hip replacement. Furthermore it has to be investigated, whether their distribution in the joint space or their transport into the bone marrow is responsible for the level of the chronic inflammatory reaction

Introduction. Nociceptive and neuropathic components both contribute to chronic pain. Since these components require different pain management strategies, correct pain diagnosis before and during treatment is important. Freynhagen et al. (2006) reported that they had developed and validated the pain-DETECT questionnaire (PD-Q) to detect neuropathic components in chronic low back pain patients. They also reported that 37% of unselected cohort of chronic LBP patients had predominantly neuropathic pain. However, the extent to which neuropathic components relate to the pathomechanism of pain deriving from osteoarthritis of hip joint remains unknown. The purpose of this study was to utilize PD-Q to investigate the relationship between neuropathic components and pain deriving from osteoarthritis of the hip joint. Methods. Between March and August 2010, 125 patients with osteoarthritis of hip joint completed PD-Qs about their pain. From this data set, we investigated whether or not the patients’ pain contained neuropathic components. Results. Only 6.4% of the patients had a score 19, indicating that a neuropathic component was likely (90%). Conversely, 79.2 % had a score 12, indicating that a neuropathic component was unlikely (15%). For the remaining 14.4% with an intermediate score (13–18), the presence of a neuropathic component remained uncertain. Conclusion. In this set of patients with osteoarthritis of hip joint, the PD-Q responses indicated that only a small percentage (6.4%) were likely to have a neuropathic component to their hip pain

Introduction. It was the purpose to evaluate the biomechanical changes that occur after optimal and non-optimal component placement of a hip resurfacing (SRA) by using a subject specific musculoskeletal model based on CT-scan data. Materials and Methods. Nineteen hips from 11 cadavers were resurfaced with a BHR using a femoral navigation system. CT images were acquired before and after surgery. Grey-value segmentation in Mimics produced contours representing the bone geometry and identifying the outlines of the 3 parts of the gluteus medius. The anatomical changes induced by the procedure were characterised by the translation of the hip joint center (HJCR) with respect to the pelvic and femoral bone. The contact forces during normal gait with ‘optimal’ component placement were calculated for a cement mantle of 3 mm, a socket inclination of 45° and anteversion of 15°. The biomechanical effect of ‘non-optimal placement’ was simulated by varying the positioning of the components. Results. There was a significant (p<0.01) shortening of the muscle length with the ‘optimal’ component placement for all parts of the gluteus medius with the largest shortening of the posterior part by 6mm. This was caused by a significant shortening of the femoral offset by 2.3mm (p<0.01). Because of a significant (p<0.01) medialisation of the HJCR by 4 mm, there was no significant increase in contact force. The hip joint contact forces increased by 0.5% per mm HJCR displacement. Each millimeter of cranial and lateral displacement of the femoral HJCR increased the contact force by 0.5% and 1%, respectively. The contact stresses changed significantly by 0.8% and 0.2% per degree of socket inclination and anteversion. The contact force increased 1% per mm lateral displacement of the acetabular HJCR. Discussion. Optimal placement of the SRA components did not completely restore the biomechanics of the native hip joint. The contact forces were not increased due to the compensatory effect of the medialisation of the acetabular HJCR. This suggests that reaming to the acetabular floor should be conducted in SRA. Femoral component displacement in the cranial and lateral direction significantly increased the hip joint loading. Errors of socket placement in the coronal and sagital plane significantly increased the contact stresses. Accumulative errors of both component displacements could lead to increased contact stresses of 18% to 23% with socket inclinations of 50° and 55°. Surgeons should reconsider continuing the SRA procedure if a neck length loss and lateralisation of the HCJR by >5 mm is anticipated as this would increase the contact stresses by >12%

Aim. To evaluate the correlation between the clinical Kirk Watson test and arthroscopic Geissler classification in scapholunate instability. Methods. All patients undergoing wrist arthroscopy between April 2006 and April 2010 were evaluated. Patients were included in the study if they had a Kirk Watson test and a wrist arthroscopy with an assessment of the stability of the scapholunate joint using the Geissler classification. Patients who had a Kirk Watson test performed with subsequent normal scapholunate joint at arthroscopy were included as a control group. Geissler grades 1 and 2 and grades 3 and 4 were grouped for further analysis into low and high grade instability groups respectively. Results. 76 patients were included in the study. 62 had scapholunate pathology and 14 had normal arthroscopic examinations of the stability of the joint. A positive test was found in 30% (3) of patients with grade 1 instability, 29% (4) with grade 2, 60% (12) with grade 3 and 78% (14) with grade 4 instability demonstrated at arthroscopy. The test was positive more commonly in those with grade IV instability compared with others (78% vs. 43%; p=0.015). There was a higher number with a negative test in the low grade instability group (71% vs. 32%; p=0.01) and a higher number with a positive test in the high grade instability group (68% vs. 29%; p=0.006). The test was most sensitive (78%) and most specific (57%) for those classified with Geissler grade IV instability and sensitivity and specificity were also high for those with high grade instability (68% and 66% respectively). Conclusions. The Kirk Watson test is a sensitive and specific test for diagnosis of higher grade instability of the scapholunate joint. We found a positive correlation between increasing scapholunate instability when assessed using the Geissler classification and positivity of the test. This confirms that the Kirk Watson test can be a useful test in the assessment of those with symptomatic instability of the joint and may reflect damage not only to the scapholunate ligament but to the secondary stabilisers of the joint as well

Femoral lengthening has been associated with narrowing of the joint space at the hip. We have studied the joint space before lengthening in 20 patients with a short femur due to a femoral-shaft fracture (15) or distal femoral epiphyseal injury (5). Their mean age at injury was 16 years (3 to 27) and the mean shortening was 5.4 cm (1.1 to 14). We found that the hip joint space of the shortened femur was significantly narrower (p < 0.001) than that on the normal side, with a mean narrowing ratio of 15.5% (−5 to +43). The narrowing ratio was directly related to the period spent non-weight-bearing (p < 0.001), but not to the amount of femoral shortening. We have shown that the joint space of the hip in patients with post-traumatic femoral shortening was narrowed even before femoral lengthening had been started

Introduction. Rapid identification of bacteria from extemporaneous samples would greatly help management of prosthesis joint infection. The aim of the present retrospective study was to evaluate a new molecular assay (GeneXpert MRSA-SA SSTI (Cepheid)) for detecting Staphylococcus aureus (SA) and methicillin resistance directly from bone and joint samples in less an hour (58 minutes). Material et method. Retrospective study using 91 frozen samples (76 patients) of joints (n=24), bone biopsies (n=42) and tissue biopsies (n=25):. -. SA positive samples: n=72 (methicillin susceptible SA (MSSA), n=63; methicillin resistant MRSA, n=9). -. SA positive samples: n=19. The results were compared with routine results (culture in solid and liquid medium, identification and susceptibility test) from each participating lab. Results. The 72 SA positive samples gave:. -. 68 concordant positive results comprising:. . 9 MRSA positive samples,. . 56 MSSA positive samples,. . 3 MSSA positive samples, positive for SA but with inconclusive results for methicillin resistance. -. 4 negative discordant results for MSSA positive samples. The 19 SA negative samples gave:. . 16 concordant negative results. . 3 SASM positive results for negative culture of samples obtained from patients with other MSSA positive deep or superficial samples, suggesting a higher sensitivity for the GeneXpert test than culture in these cases. Sensitivity and specificty for bone and joint samples:. Se=68/72=94.4%. Sp=16/16=100%. Conclusion. The GeneXpert MRSA-SA SSTI assay provides 58-minute detection of MSSA and MRSA directly from bone and joint samples. Sensitivity and specificity were excellent in this preliminary study. This test may enable real-time peroperative diagnosis of Staphylococcus aureus, which could be very useful in the field of revision surgery. Further prospective studies should be done to accurately determine the PPV, NPV, and clinical and pharmaco-economic impact of this test in the setting of prosthesis joint infection

INTRODUCTION. Hip wear simulator test results could be affected by many non-bearing related factors such as fixation surface conditions, equipment calibration and component set-up. In an effort to improve the accuracy, reliability and repeatability of hip simulator test, a quality management system has been established at the IDC hip tribology laboratory, which has been accredited by UKAS (United Kingdom Accreditation Service) in accordance with the recognised international standard ISO17025. This study demonstrates that under well-controlled laboratory and testing conditions, satisfactory repeatability can be achieved during hip simulator studies. METHODS. Between 2008 to 2010, ten 50 mm Birmingham Hip Resurfacing (BHR) devices were tested by the IDC tribology laboratory using two ProSim hip wear simulators in three different tests (T1, T2 and T3). All tests were performed following the same IDC testing protocols at 1 Hz frequency for 5 million cycles (Mc) or until after a steady state was reached. Paul type stance phase loadings with a maximum load of 3 kN and a swing phase load of 0.3 kN was used. The flexion and extension angles were 30 and 15 degree. The internal/external rotation angel was ±10 degree. Wear was measured gravimetrically using an analytical balance (Mettler, Toledo xp504) with an accuracy of 0.1 mg. RESULTS. Results showed that wear of all the components tested followed the typical biphasic trend of wear for MoM hip joint device with a high “running-in” wear during the initial stage followed by a low “steady state” wear in the later stage. The data points scattered in a narrow range following the same trend line throughout the tests. The maximum difference in accumulated volume loss between any two tests at any given cycle was less in 0.2 mm3. The average running-in wear rates (±SD) were 0.72 ±0.17, 0.86 ±0.01 and 0.71 ±0.19 mm3/Mc respectively for test T1, T2 and T3. The running-in wear rates for test T1 and T3 were identical, whilst that for T2 was slightly higher. In spite of this, the wear rates for the bearings tested in T2 were still in the same range as those tested in T1 and T3 during the running-in stage. The steady state (>1.0Mc) wear rate of three different tests was practically the same, being 0.18 ±0.02, 0.18 ±0.06 and 0.16 ±0.04 mm3/Mc respectively for test T1, T2 and T3. Overall, the mean running-in wear rate was 0.74 ±0.16 mm3/Mc, and the steady state wear rate was 0.17 ±0.04 mm3/Mc for the 10 BHR devices tested in three different studies. DISCUSSIONS. This study shows that satisfactory repeatability can be achieved during hip simulator test of metal on metal hip joint devices. Well controlled test procedures including calibration of testing and measurement equipment, correct and consistence test set-up and attention to non-bearing surfaces are some of the most important prerequisites for reliable and accurate hip simulator test results

Background. Acute anterior dislocation of the glenohumeral joint may be complicated by injury to neighboring structures. These injuries are best considered a spectrum of injury ranging from an isolated dislocation (unifocal injury), through injuries associated with either nerve or osteoligamentous injury (bifocal injury), to injuries where there is evidence of both nerve and osteoligamentous injury. The latter combination has previously been described as the “terrible triad,” although we prefer the term “trifocal,” recognizing that this is the more severe end of an injury spectrum and avoiding confusion with the terrible triad of the elbow. We evaluated the prevalence and risk factors for nerve and osteoligamentous injuries associated with an acute anterior glenohumeral dislocation in a large consecutive series of patients treated in our Unit. Materials and Methods. 3626 consecutive adults (mean age 48yrs) with primary traumatic anterior shoulder dislocation treated at our unit were included. All patients were interviewed and examined by an orthopaedic trauma surgeon and underwent radiological assessment within a week of injury. Where rotator cuff injury or radiologically-occult greater tuberosity fracture was suspected, urgent ultrasonography was used. Deficits in neurovascular function were assessed clinically, with electrophysiological testing reserved for equivocal cases. Results. Unifocal injuries occurred in 2228 (61.4%) of patients. There was a bimodal distribution in the prevalence of these injuries, with peaks in the 20–29 age cohort (34.4% patients) and after the age of 60 years (23.0% patients). Of the 1120 (30.9%) patients with bifocal dislocations, 920 (82.1%) patients had an associated osteotendinous injury and 200 (17.9%) patients had an associated nerve injury. Trifocal injuries occurred in 278 (7.7%) of cases. In bifocal and trifocal injuries, rotator cuff tears and fractures of the greater tuberosity or glenoid were the most frequent osteotendinous injuries. The axillary nerve was most frequently injured neurological structure. We were unable to elicit any significant statistical differences between bifocal and trifocal injuries with regards to patient demographics. However, when compared with unifocal injuries, bifocal or trifocal injuries were more likely to occur in older, female patients resulting from low energy falls (p<0.05). Conclusions. We present the largest series reporting the epidemiology of injury patterns related to traumatic anterior shoulder dislocation. Increased understanding and awareness of these injuries among clinicians will improve diagnosis and facilitate appropriate treatment