Cerebral Palsy (CP) is a group of disorders that affect movement and posture caused by injury to the developing brain. While prematurity and low birth weight are common causes in developed countries, birth asphyxia, kernicterus, and infections have been identified as predominant aetiologies in Africa. There is, however, very little information on the aetiology of CP in South Africa. The purpose of this study was to determine the aetiology, severity, and topographical distribution of CP in children undergoing orthopaedic surgery at our tertiary paediatric unit. A retrospective folder review was performed for patients with CP that underwent orthopaedic surgery from July 2018 to June 2022. Data was collected on perinatal circumstances, aetiology or risk factors for developing CP, severity of disability as classified by the Gross Motor Function Classification Scale (GMFCS) and topographical distribution. Descriptive analysis was performed. Two-hundred-and-thirty-four patients were included in the analysis. No specific aetiology could be identified in 51 (21.9%) patients. Hypoxic ischaemic encephalopathy (HIE) accounted for 23.6% of patients and was the most common aetiology across the different categories except for patients graded as GMFCS 2, in whom prematurity was the most common aetiology. Congenital brain malformations (10.5%) and cerebral infections, including HIV encephalopathy (11.4%) were the next most frequent aetiologies, followed by prematurity (7.6%), ischaemic stroke (6.8%) and intraventricular haemorrhage (6.3%). Fifty-two percent of patients were classified as GMFCS 4 or 5. There was a predominance of quadriplegic patients (37%) compared to hemiplegics (29%), diplegics (30%) and monoplegics (4%). Most patients undergoing orthopaedic surgery for musculoskeletal sequelae of CP were severely disabled quadriplegic patients in whom HIE was the predominant cause of CP. This emphasises the need for intervention at a primary care level to decrease the incidence of this frequently preventable condition

Purpose. Fracture-related infection (FRI) is an important complication related to orthopaedic trauma. Although the scientific interest with respect to the diagnosis and treatment of FRI is increasing, data on the microbiological epidemiology remains limited. Therefore, the primary aim of this study was to evaluate the microbiological epidemiology related to FRI, including the association with clinical symptoms and antimicrobial susceptibility data. The secondary aim was to analyze whether there was a relationship between the time to onset of infection and the microbiological etiology of FRI. Methods. Over a five-year period, FRI patients treated at the University Hospitals of Leuven, Belgium, were retrospectively included. The microbiological etiology and antimicrobial susceptibility data were analyzed. Patients were classified as having an early (<2 weeks after implantation), delayed (2–10 weeks) or late-onset (> 10 weeks) FRI. Results. One hundred ninety-one patients with 194 FRIs, mainly involving the tibia (23.7%) and femur (18.6%), were included. Staphylococcus aureus was the most frequently isolated pathogen, regardless of time to onset (n=61; 31.4%), followed by S. epidermidis (n=50; 25.8%) and non-epidermidis coagulase-negative staphylococci (n=35; 18.0%). Polymicrobial infections (n=49; 25.3%), mainly involving Gram-negative bacilli (n=32; 65.3%), were less common than monomicrobial infections (n=138; 71.1%). Virulent pathogens in monomicrobial FRIs were more likely to cause pus or purulent discharge (n=45;54.9%; p=0.002) and fistulas (n=21;25.6%; p=0.030). Susceptibility to piperacillin/tazobactam for GNB was 75.9%. Vancomycin covered 100% of Gram-positive cocci. Conclusion. The high frequency of polymicrobial infections, including Enterobacterales and enterococci, should be considered when choosing an empirical regimen, especially for early FRI. However, since antibiotic stewardship is the cornerstone of good antibiotic practice, overuse and misuse of broad-spectrum empiric therapy should be avoided at all costs. Large multicenter prospective studies are necessary to gain more insight into the added value of (broad) empirical antibiotic therapy

Aims. Advances in surgical technique and implant design may influence the incidence and mechanism of failure resulting in revision total hip arthroplasty (rTHA). The purpose of the current study was to characterize aetiologies requiring rTHA, and to determine whether temporal changes existed in these aetiologies over a ten-year period. Methods. All rTHAs performed at a single institution from 2009 to 2019 were identified. Demographic information and mode of implant failure was obtained for all patients. Data for rTHA were stratified into two time periods to assess for temporal changes: 2009 to 2013, and 2014 to 2019. Operative reports, radiological imaging, and current procedural terminology (CPT) codes were cross-checked to ensure the accurate classification of revision aetiology for each patient. Results. In all, 2,924 patients with a mean age of 64.6 years (17 to 96) were identified. There were 1,563 (53.5%) female patients, and the majority of patients were Caucasian (n = 2,362, 80.8%). The three most frequent rTHA aetiologies were infection (27.2%), aseptic loosening (25.2%), and wear (15.2%). The frequency of rTHA for adverse local tissue reaction (ALTR) was significantly greater from 2014 to 2019 (4.7% vs 10.0%; p < 0.001), while the frequency of aseptic loosening was significantly greater from 2009 to 2013 (28.6% vs 21.9%; p < 0.001). Conclusion. Periprosthetic joint infection was the most common cause for rTHA in the current cohort of patients. Complications associated with ALTR necessitating rTHA was more frequent between 2014 to 2019, while aseptic loosening necessitating rTHA was significantly more frequent between 2009 to 2013. Optimizing protocols for prevention and management of infection and ALTR after THA may help to avoid additional financial burden to institutions and healthcare systems. Cite this article: Bone Joint Open 2020;2(1):16–21

Flat-top talus (FTT) is a complication well-known to those treating clubfoot. Despite varying anecdotal opinions, its association with different treatments, especially the Ponseti method, remains uncertain. This systematic review aimed to establish the aetiology and prevalence of FTT, as well as detailing management strategies and their efficacy. A systematic review was conducted according to PRISMA guidelines to search for articles using MEDLINE, EMBASE and Web of Science until November 2021. Studies with original data relevant to one of three questions were included: 1) Possible aetiology 2) Prevalence following different treatments 3) Management strategies and their outcomes. 32 original studies were included, with a total of 1473 clubfeet. FTT may be a pre-existing feature of the pathoanatomy of some clubfeet as well as a sequela of treatment. It can be a radiological artefact due to positioning or other residual deformity. The Ponseti method is associated with a higher percentage of radiologically normal tali (57%) than both surgical methods (52%) and non-Ponseti casting (29%). Only one study was identified that reported outcomes after surgical treatment for FTT (anterior distal tibial hemiepiphysiodesis). The cause of FTT remains unclear. It is seen after all treatment methods but the rate is lowest following Ponseti casting. Guided growth may be an effective treatment. Key words:. Clubfoot, Flat-top talus, Ponseti method, guided growth. Disclosures: The authors have no relevant disclosures

Aims. The glenohumeral joint is the most frequently dislocated articulation, but possibly due to the lower prevalence of posterior shoulder dislocations, approximately 50% to 79% of posterior glenohumeral dislocations are missed at initial presentation. The aim of this study was to systematically evaluate the most recent evidence involving the aetiology of posterior glenohumeral dislocations, as well as the diagnosis and treatment. Materials and Methods. A systematic search was conducted using PubMed (MEDLINE), Web of Science, Embase, and Cochrane (January 1997 to September 2017), with references from articles also evaluated. Studies reporting patients who experienced an acute posterior glenohumeral joint subluxation and/or dislocation, as well as the aetiology of posterior glenohumeral dislocations, were included. Results. A total of 54 studies met the inclusion criteria. In total, 182 patients were included in this analysis; study sizes ranged from one to 66 patients, with a mean age of 44.2 years (. sd. 13.7). There was a higher proportion of male patients. In all, 216 shoulders were included with 148 unilateral injuries and 34 bilateral. Seizures were implicated in 38% of patients (n = 69), with falls, road traffic accidents, electric shock, and iatrogenic reasons also described. Time to diagnosis varied across studies from immediate up to a delay of 25 years. Multiple associated injuries are described. Conclusion. This review provides an up-to-date insight into the aetiology of posterior shoulder dislocations. Our results showed that seizures were most commonly implicated. Overall, reduction was achieved via open means in the majority of shoulders. We also found that delayed diagnosis is common

Femoroacetabular impingement causes pain in the hip in young adults and may predispose to the development of osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis of the hip and may have a role in that of femoroacetabular impingement. We compared 96 siblings of 64 patients treated for primary impingement with a spouse control group of 77 individuals. All the subjects were screened clinically and radiologically using a standardised protocol for the presence of cam and pincer deformities and osteoarthritis. The siblings of those patients with a cam deformity had a relative risk of 2.8 of having the same deformity (66 of 160 siblings hips versus 23 of 154 control hips, p < 0.00001). The siblings of those patients with a pincer deformity had a relative risk of 2.0 of having the same deformity (43 of 116 sibling hips versus 29 of 154 control hips, p = 0.001). Bilateral deformity occurred more often in the siblings (42 of 96 siblings versus 13 of 77 control subjects, relative risk 2.6, p = 0.0002). The prevalence of clinical features in those hips with abnormal morphology was also greater in the sibling group compared with the control group (41 of 109 sibling hips versus 7 of 46 control hips, relative risk 2.5, p = 0.007). In 11 sibling hips there was grade-2 osteoarthritis according to Kellgren and Lawrence versus none in the control group (p = 0.002). Genetic influences are important in the aetiology of primary femoroacetabular impingement. This risk appears to be manifested through not only abnormal joint morphology, but also through other factors which may modulate progression of the disease

Objectives. A successful outcome following treatment of nonunion requires the correct identification of all of the underlying cause(s) and addressing them appropriately. The aim of this study was to assess the distribution and frequency of causative factors in a consecutive cohort of nonunion patients in order to optimise the management strategy for individual patients presenting with nonunion. Methods. Causes of the nonunion were divided into four categories: mechanical; infection; dead bone with a gap; and host. Prospective and retrospective data of 100 consecutive patients who had undergone surgery for long bone fracture nonunion were analysed. Results. A total of 31% of patients had a single attributable cause, 55% had two causes, 14% had three causes and 1% had all four. Of those (31%) with only a single attributable cause, half were due to a mechanical factor and a quarter had dead bone with a gap. Mechanical causation was found in 59% of all patients, dead bone and a gap was present in 47%, host factors in 43% and infection was a causative factor in 38% of patients. In all, three of 58 patients (5%) thought to be aseptic and two of nine (22%) suspected of possible infection were found to be infected. A total of 100% of previously treated patients no longer considered to have ongoing infection, had multiple positive microbiology results. Conclusion. Two thirds of patients had multiple contributing factors for their nonunion and 5% had entirely unexpected infection. This study highlights the importance of identifying all of the aetiological factors and routinely testing tissue for infection in treating nonunion. It raises key points regarding the inadequacy of a purely radiographic nonunion classification system and the variety of different definitions for atrophic nonunion in the current mainstream classifications used for nonunion. Cite this article: L. Mills, J. Tsang, G. Hopper, G. Keenan, A. H. R. W. Simpson. The multifactorial aetiology of fracture nonunion and the importance of searching for latent infection. Bone Joint Res 2016;5:512–519. DOI: 10.1302/2046-3758.510.BJR-2016-0138

1. During a fifteen-year period a clinical, radiological and in some cases a surgical study has been made of 319 patients suffering from spondylolisthesis–that is, forward slipping of one lumbar vertebra on another or forward sagging of the whole lumbar spine in relation to the sacrum. 2. The five etiological factors are described, and the cases are assigned to five groups according to the factor responsible for the slip. In every case slipping is permitted by a lesion of the apparatus which normally resists the forward thrust of the lower lumbar spine–that is, the hook of the neural arch composed of the pedicle, the pars interarticularis and the inferior articular facet engaging caudally over the superior articular facet of the vertebra below. 3. In Group I (congenital spondylolisthesis–sixty-six cases) the lesion is a congenital defect of the facets. In Group II (spondylolytic spondylolisthesis–164 cases) the lesion occurs in the region of the pars interarticularis and is either an elongation of the bone or a break in continuity. There are reasons for thinking that the lesion is caused by stress over a long period rather than by acute injury or by a congenital anomaly of ossification. In Group IV (degenerative spondylolisthesis–eighty cases) the lesion of the facets is degenerative. There are no good grounds for thinking that an abnormality of the angle between the facets and the pedicles is the primary lesion behind the degenerative change. 4. Group III and V comprise few cases. In the former (traumatic spondylolisthesis–three cases) the lesion–a fracture of the neural arch–is caused by a single severe injury. In Group V (pathological spondylolisthesis–six cases) the slipping is caused by weakness of bone from various causes. 5. A full description is given of the etiological and biomechanical features of each group. A special investigation has been made into the etiological factors in degenerative spondylolisthesis. 6. The incidence of involvement of nerve tissues is highest in degenerative spondylolisthesis; the most severe degrees of slip are found in congenital spondylolisthesis

1 . Current theories of the etiology of chondromalacia patellae do not explain satisfactorily either its great frequency or its common site of origin on the medial patellar facet. 2. The etiology can be more logically explained by the presence of a ridge on the upper anterior border of the cartilage of the medial femoral condyle, in most knees. This ridge, consisting of cartilage, or cartilage and bone, varies considerably in height and, in normal knee joint movement, causes considerable friction on the medial patellar facet. 3. The degenerative changes were found to be greater in the presence of the larger ridges, and–because of longer wear and tear–in the older patients. 4. This study indicates that chondromalacia was more severe in women than in men, and in patients overweight. Although the activity of the individual and the power of the quadriceps mechanism must play an extremely important part in this condition, it was not possible to assess this. 5. Two factors previously considered to be important in the etiology of this condition, namely, the length of the patellar tendon and Wiberg's Type III patellar shape, have not been confirmed in this study. 6. Resulting from the present investigation certain precautions are suggested in rehabilitation after operations on the knee, and a surgical method for discouraging the progress of this common, and sometimes disabling, condition has been devised

Stiffness after TKR is a frustrating complication that has many possible causes. Though the definition of stiffness has changed over the years, most would agree that flexion > 75 degrees and a 15-degree lack of extension constitutes stiffness. This presentation will focus upon the potential causes of a stiff TKR, intra-operative tips, the post-operative evaluation and management, and the results of revision for a stiff TKR. The management of this potentially unsatisfying situation begins pre-operatively with guidance of the patient's expectations; it is well-known that pre-operative stiffness is strongly correlated with post-operative lack of motion. At the time of surgery, osteophytes must be removed and the components properly sised and aligned and rotated. Soft-tissue balancing must be attained in both the flexion/extension and varus/valgus planes. One must avoid overstuffing the tibio-femoral and/or patello-femoral compartments with an inadequate bone resection. Despite these surgical measures and adequate pain control and rehabilitation, certain patients will continue to frustrate our best efforts. These patients likely have a biological predisposition for formation of scar tissue. Other potential causes for the stiff TKR include complex regional pain syndrome or joint infection. Close followup of a patient's progress is crucial for the success in return of ROM. Should motion plateau early in the recovery phase, the patient should be evaluated for manipulation under anesthesia. At our institution, most manipulations are performed within 3 months post-operative under an epidural anesthetic; patients will stay overnight for continuous epidural pain relief and immediate aggressive PT. The results of re-operations for a stiff TKR are variable due to the multiple etiologies. A clear cause of stiffness such as component malposition, malrotation or overstuffing of the joint has a greater chance of regaining motion than arthrofibrosis without a clear cause. Although surgical treatment with open arthrolysis, isolated component or complete revision can be used to improve TKR motion, results have been variable and additional procedures are often necessary

Aims

Avascular femoral head necrosis in the context of gymnastics is a rare but serious complication, appearing similar to Perthes’ disease but occurring later during adolescence. Based on 3D CT animations, we propose repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension and external rotation as a possible cause of direct vascular damage, and subsequent femoral head necrosis in three adolescent female gymnasts we are reporting on.

A nationwide study of Perthes’ disease in Norway was undertaken over a five-year period from January 1996. There were 425 patients registered, which represents a mean annual incidence of 9.2 per 100 000 in subjects under 15 years of age, and an occurrence rate of 1:714 for the country as a whole. There were marked regional variations. The lowest incidence was found in the northern region (5.4 per 100 000 per year) and the highest in the central and western regions (10.8 and 11.3 per 100 000 per year, respectively). There was a trend towards a higher incidence in urban (9.5 per 100 000 per year) compared with rural areas (8.9 per 100 000 per year). The mean age at onset was 5.8 years (1.3 to 15.2) and the male:female ratio was 3.3:1. We compared 402 patients with a matched control group of non-affected children (n = 1 025 952) from the Norwegian Medical Birth Registry and analysed maternal data (age at delivery, parity, duration of pregnancy), birth length and weight, birth presentation, head circumference, ponderal index and the presence of congenital anomalies. Children with Perthes’ disease were significantly shorter at birth and had an increased frequency of congenital anomalies. Applying Sartwell’s log-normal model of incubation periods to the distribution of age at onset of Perthes’ disease showed a good fit to the log-normal curve. Our findings point toward a single cause, either genetic or environmental, acting prenatally in the aetiology of Perthes’ disease

The aim of school screening is to identify most or all the individuals with unrecognized idiopathic scoliosis (IS) at an early stage when a less invasive treatment is more effective. The present study summarises the contribution of school screening in research of IS epidemiology, natural history and aetiology. In addition, school screening is a unique tool for research of IS in humans, as in most published articles, all aetiopathogenetic factors are studied in animals and not in humans. Such contribution is beyond the original aim of school screening but is very important to expand our knowledge and adequately understand the pathogenesis of IS. The role of biological factors such as the menarche, the lateralization of the brain, the handedness, the thoracic cage, the intervertebral disc, the melatonin secretion, as well as the role of environmental factors such as the light and the impact of the geographical latitude in IS prevalence were studied in children referred from school screening. The present study provides evidence to support that school screening programs should be continued not only for early detection of IS but also as a basis for epidemiological surveys until we learn much more about the aetiology of IS

The purpose of this study was to identify aetiological that may determine prognosis in ulnar nerve lesions and to evaluate the role of non-operative treatment. 148 consecutive patients (100 male) with 170 electrophysiologically proven (by nerve conduction and electromyography) ulnar nerve lesions were identified from the departmental records. Patient details, symptoms, known aetiology and treatment profile were recorded. Each patient was then contacted by telephone and/or questionnaire 1–6 (median 3. 8) years following electrodiagnosis to determine clinical progress and outcome. In patients with sensory symptoms alone or non-progressive painless motor symptoms, non-operative treatment was commenced. This involved advice on activity modifications and protection with a tubipad bandage or night spin. 12. 9% and 8. 8% of lesions were due to injury and intra-operative pressure respectively. Other causes included deformity and/or synovitis from arthritis of the elbow, repeated pressure, medial epicondylitis and benign space occupying lesions. 58. 2% were idiopathic with no clinical aetiological factor. 22 patients had expected bilateral lesions whereas 15 had contralateral lesions that were not symptomatic. 89. 4% and 4. 7% of lesions occurred at the elbow and wrist respectively. 83% of patients received non-operative first line treatment. 21% of these required operative intervention following further clinical and electrophysiological assessment. Partial or complete recovery occurred in 80%, 67% and 52% of the intra-operative, idiopathic and injury cases respectively (P< 0. 05). We conclude lesions of the ulnar nerve predominate in males and can be treated non-operatively providing clinical and electrophysiological monitoring is possible. Bilaterality is not uncommon and should be excluded. Lesions due to injury have a worse prognosis than those caused by direct continuous or repeated pressure or where no aetiological factor exists

Introduction: Femoroacetabular impingement (FAI) causes pain in young adults and osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis. We aimed to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls. Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. Probands were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of their 77 partners and was age and gender-matched. All subjects were assessed clinically and radiologically (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and morphological abnormalities. Participants were classified as:. Normal morphology, no clinical features. Abnormal morphology, no clinical features. Abnormal morphology, clinical signs but no symptoms. Abnormal morphology with symptoms and signs. Osteoarthritis. Results: The sibling relative risks were significant for groups b, c, and d (ranging between 2–5, p< 0.01). Pro-bands and siblings shared the same pattern of abnormal morphology. Gender specificity was apparent: pincer abnormalities common in sisters but not in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, but only 50% of sisters did. Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during development warrants further study. Symptoms are variable, indicating a spectrum of disease progression. These cohorts present an opportunity to prospectively study the natural history of the condition, improve understanding of the mechanisms and pathology, and potentially to be recruited into clinical trials

1. Chondromalacia of the patella starts most frequently on the medial facet. 2. The anatomy of the medial femoral condyle is described, including the rim at its superior border, and the different arrangement at the upper border of the lateral femoral condyle. 3. Rubbing of the medial patellar facet on the rim at the upper border of the medial femoral condyle can explain in part the etiology of chondromalacia

A five-year prospective trial involving 120 patients was undertaken to investigate the aetiology and treatment of coccydynia. The cause lies in some localised musculoskeletal abnormality in the coccygeal region. Lumbosacral disc prolapse is not a significant factor. The condition is genuine and distressing and we found no evidence of neurosis in our patients. Physiotherapy was of little help in treatment but 60% of patients responded to local injections of corticosteroid and local anaesthesia. Manipulation and injection was even more successful and cured about 85%. Coccygectomy was required in almost 20% and had a success rate of over 90%

Introduction: Femoroacetabular impingement (FAI) is an important cause of hip pain in young adults and a precursor to osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis of the hip. From a research perspective, FAI is an example of how subtle morphological abnormality results in a predictable pattern of cartilage damage, and thereby offers great potential as a model to study early degenerative disease. Although many causes of FAI are described, the vast majority of patients give no history of previous hip disease. The purpose of this study was to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls. Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. These patients were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of the 77 partners of those siblings (40 male, 37 female, mean age 41.9 years). All subjects underwent clinical (interview, examination, and hip scores) and radiological assessment (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and cam- and pincer-type abnormalities. Results: Participants were classified as a) Normal morphology with no clinical features, b) Abnormal morphology but no clinical features c) Abnormal morphology with clinical signs but no symptoms, and d) Abnormal morphology with symptoms and signs. The sibling relative risks were significant for groups b, c, and d, supporting the hypothesis of an underlying genetic predisposition to FAI. Siblings usually demonstrated the same type of abnormal morphology as the proband. Gender specificity was apparent however, with pincer abnormalities which were usually apparent in female probands being common in sisters but less common in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, although only 50% of sisters did so. Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during maturity warrants further study. We have identified a spectrum of disease with a proportion of siblings with abnormal morphology currently asymptomatic. These cohorts present an opportunity to prospectively study the natural history of the condition, improve our understanding of the mechanisms and pathology in early degenerative disease, and potentially to be recruited into clinical trials of surgical and adjuvant treatments

Over the long term, the results of the insertion of a Grammont inverted shoulder prothesis are unknown. The present study reports survivorship curves and the role of the initial aetiology in patients re-examined after 5 to 10 years. Patients and methods Eighty prostheses (for 77 patients) were implanted between 1992 and 1998: 66 cases of massive cuff tear arthropathy (MCTA) and 24 cases for another aetiology (mainly rheumatoid arthritis and revision). At the time of follow-up, 18 patients had died and 2 could not be traced. The remaining patients (57 representing 60 prostheses) were seen by an independent examiner. The minimum follow-up was 5 years. The average follow-up was 69,6 months. Kaplan-Meir survivorship curves for the 60 prostheses were established in order to show the probability of failure as defined by: revision of the prothesis, glenoid loosening, and a functional level< 30 points according to the Constant score. Results The survivorship curves were as follow:. - for non revision of the prosthesis at 10 years: 91% overall; after 9 years: 95% for MCTA, and 77 % for the others aetiologies. This difference was statistically significant (p< 0,01) ; 6 implants were revised: 3 for MCTA and 3 for other aetiologies. - for non glenoid loosening at 10 years: 84 % overall ; after 7 years: 91% for MCTA and 77% for other aetiologies. This difference was statistically significant (p< 0,05). In addition to the cases of replaced implants mentioned above there was a case of glenoid loosening after 8 years follow-up in a patient aged 92. -for Constant score < 30 at 10 years: 58 % overall. The punctual survivorship rate was significantly different in function of the aetiology, at 6 years ; but this was no longer the case after 7 years. Discussion. According to revision of the prosthesis, there is a clear rupture in the survivorship curve about 3 years after insertion in aetiologies other than MCTA. This suggests that Grammont inverted total shoulder arthroplasty is not appropriate in these aetiologies (particularly in cases of rheumatoid arthritis). According to Constant score < 30, there is a clear rupture in the survivorship curve about 7 years after insertion specially in MCTA cases. This suggests that inverted protheses should be used only in cases with severe handicap and only in patients aged over 75

The purpose of this study was to identify aetiological factors that may determine prognosis in ulnar nerve lesions at the elbow and to evaluate the role of non-operative treatment. One hundred and thirty consecutive patients (92 male) with 152 electrophysiologically proven (by nerve conduction and electromyography) ulnar nerve lesions at the elbow were identified from the departmental records. Patient details, symptoms, known aetiology and treatment profile were recorded. Each patient was then contacted by telephone and / or questionnaire between one and six years after electrodiagnosis to determine clinical progress and outcome. In patients with sensory symptoms alone or non-progressive painless motor symptoms, non-operative treatment was commenced. This involved advice on activity modification and protection with a tubipad bandage or night splint with continued clinical and electrophysiological surveillance. Sixty-one percent of lesions were idiopathic with no clinical aetiological factor. Defined causes included deformity and/or synovitis from arthritis of the elbow (11.2%), injudicious intra-operative pressure (9.2%), injury/trauma (8.5%) repeated pressure (4.1%), medial epicondylitis (2.9%) and benign space occupying lesions (2.9%). Twenty-two patients had expected bilateral lesions whereas 15 had contralateral lesions that were not symptomatic. Eighty-three percent of patients received non-operative first line treatment. Twenty-one percent of these required operative intervention (simple decompression) following further clinical and electrophysiological assessment. Partial or complete recovery occurred in 88%, 80%, 67% and 52% of the arthritis, intra-operative, idiopathic and injury cases respectively (P< 0.05). We conclude lesions of the ulnar nerve at the elbow predominate in males and the majority can be treated non-operatively providing clinical and electrophysiological monitoring is possible. Bilaterality is not uncommon and should be excluded. Lesions due to injury have a worse prognosis than those caused by arthritis of the elbow, direct continuous or repeated pressure or where no aetiological factor exists

Surfing is a popular UK water-sport. Recommendations for protective gear are based on studies abroad from trauma from large waves and reef breaks which may not be relevant in the UK. This study assesses the aetiology of UK surfing injuries in order to assist treatment and provide formative recommendations on protective equipment. Data was collected from UK surf clubs via an online survey. 130 individuals reported 335 injuries. M:F ratio 85:45, median age 28 (range 17–65). Head injuries were the most common (24%) followed by foot and ankle (19%). Surfers collided most often with their own boards (31%) followed by rocks/coral (15%), the sea (11%) and other surf boards (10%). Lacerations were the commonest injury (31%); followed by bruises/ black-eyes (24%) and joint/ligament sprains (15%). Concussions (5%), fractures (3%) and teeth injuries (1%) were rare. Less than 1/3 of all injuries required professional medical attention, 2 required operative intervention. Surfing injuries in the UK are common but usually minor. Serious head injuries (fractures and concussions) are rare. There is insufficient evidence to warrant the routine use of protective helmets whilst surfing in the UK, although protective head and foot gear may be considered when surfing the rarer reef/ rock breaks

Introduction: This is a prospective study of a series of consecutive cases of Os Odontoideum focussing on CT and MRI data. Both congenital and post-traumatic aetiologies have been proposed in the literature. This can lead to confusion in a medico-legal and clinical setting. Methods: Radiological, CT and MRI data from 26 consecutive cases of cranio-cervical anomalies were collected prospectively. Demographic details, the presence of any recent or remote traumatic aetiology and the clinical presentation were obtained from the medical record. A reconstructed mid-sagittal CT was examined for the thickness of the arch of C1, the size and location of the Os and the morphology of the atlantodens joint. The presence of any cord impression or signal change was obtained from the MRI. Results: 18 cases of Os Odontoideum were identified. Only one had a history of significant trauma remote from presentation. All adults had an abnormal archdens joint configuration (the ‘Jigsaw’ sign) with one exception. The atlantodens ratio was significantly greater in all cases of Os odontoideum indicating a relatively thickened anterior arch of the atlas. One case of non-union of a dens fracture presenting five or more years after the injury was identified in this series. Neither in this case nor two cases of transverse ligament rupture and two cases of Ossiculum terminale, was a thickened arch or an abnormal atlantodens joint observed. 12 of the cases presented after traumatic injury to the neck. In only three of these was there any abnormal neurological signs. Conclusions: Os Odontoideum has a characteristic appearance of the anterior C1 arch and the atlantodens joint as viewed on CT. These radiological signs are not observed after dens fractures. They may be taken to indicate a congenital aetiology for the condition. Patients with Os odontoideum are able to tolerate moderate to severe levels of injury without sustaining significant acute cord damage

At the apex of an idiopathic scoliotic curve there is a greater proportion of "slow twitch" muscle fibres in multifidus on the convex as compared to the concave side. To determine whether this represents a primary muscular imbalance relevant to the aetiology of idiopathic scoliosis or merely a secondary change, the lengths of multifidus on opposite sides of the curve were measured. Multifidus is shorter on the convex side. This is consistent with the theory of primary muscular imbalance, in which the more tonically acting muscle with its higher proportion of "slow twitch" fibres contracts and shortens as the deformity is produced. The paradox of multifidus being shorter on the convex rather than on the concave side is explained by consideration of its action

A study of the natural history and aetiology of deep vein thrombosis in 499 patients after total hip replacement is presented. Deep vein thrombosis was diagnosed by scanning the leg for 125Iodine-labelled fibrinogen for a period of 14 to 18 days and by ascending phlebography. It has been shown that deep vein thrombosis occurs ater than in patients who have undergone abdominal operations, and the risk period is longer. The peak of onset of thrombosis is on the fourth day after the hip replacement. Attempts at prophylaxis using subcutaneous heparin or intermittent pneumatic compression of the calves delay the appearance of thrombosis. Analysis of possible aetiology factors shows that the age of the patient, the degenerative disease of the hip, the surgical approach, and under-transfusion of blood, all have a significant effect on the incidence of thrombosis

Aims

Despite numerous studies on periprosthetic joint infections (PJI), there are no robust data on the risk factors and timing of metachronous infections. This study was performed to answer the following questions: 1) Is there any difference of manifestation time of metachronous PJIs between different localizations of multiple artificial joints? 2) Can we identify any specific risk factor for metachronous PJIs for different localizations of multiple artificial joints?

Introduction Both congenital and acquired aetiologies for Os Odontoideum have been proposed leading to confusion in a medico-legal setting. No large series with CT and MRI features has been reported. Methods Clinical, radiological, CT and MRI data from 25 cases of cranio-cervical anomalies (including 18 with Os Odontoideum) was collected prospectively. The hypothesis that Os Odontoideum is associated with signs of dysplasia such as arch hypertrophy (as quantified by the arch-peg ratio) and a ‘jigsaw’ like atlanto-dens joint configuration was tested. Results Only one of 18 cases with Os Odontoideum gave a history of remote trauma. None of the cases with other post traumatic conditions showed arch hypertrophy or dysplasia of the joint. Os Odontoideum was associated with two distinctive features on mid-sagittal CT reconstruction: arch hypertrophy and the presence of a ‘jigsaw sign’. A quantitative definition of arch hypertrophy (an arch/ peg ratio greater than 0.5) provided a sensitive and specific test for Os Odontoideum. This was further enhanced in combination with the jigsaw sign to give a test accuracy of 97%. Motor changes with MRI signs of cord damage were observed in one of 12 cases associated with trauma. Conclusions The lack of a history of remote trauma and the dyplastic atlanto-dens joint seen on CT are more suggestive of a congenital than a post-traumatic aetiology for Os Odontoideum. Patients with Os odontoideum are able to tolerate moderate to severe levels of injury without sustaining significant acute cord damage

1. Breech malposition and hormonal joint laxity produce atraumatic posterior dislocations in the hip joints of young rabbits. 2. Experimental studies were shown to cause the development of a limbus and other softtissue changes similar to those found in human congenital dislocations. 3. The development of femoral retroversion and anteversion in the presence of joint laxity is described. 4. The co-existence of breech malposition and hormonal joint laxity in utero, and their importance as prime factors in the etiology of congenital dislocation of the hip, are discussed

1. Peroneal spastic flat foot is a term loosely and often inaccurately used to describe rigid valgus feet developing from widely different causes. 2. The most common causes are two anomalies of the bones of the tarsus—the calcaneonavicular bar, and the talocalcaneal bridge. The first was described in 1921 by Sloman and in 1927 by Badgley; the other is described for the first time in this paper as an etiological factor in rigid flat foot though it has been recognised by anatomists for fifty years as a skeletal variation. The term peroneal spastic flat foot, as applied to these cases, is inaccurate since there is no spasm of the peroneal muscles. The deformity is a fixed structural deformity due to anomalous bone structure, and the apparent spasm of peroneal muscles is in reality an adaptive shortening. A better term would be rigid flat foot due to talocalcaneal bridge or calcaneonavicular bar. 3. The smaller group of patients who suffer from inflammatory lesions of the tarsal joints, chiefly due to rheumatoid arthritis, do in fact develop valgus deformity from peroneal spasm. The resemblance between the two groups is superficial and it is limited to the apparent similarity of the deformity. Though it might be justifiable to designate this type as peroneal spastic flat foot, it would be better to use the more accurate title—arthritic flat foot with peroneal spasm. 4. Lipping of the upper margin of the talonavicular joint strongly suggests the existence of one or other of the congenital anomalies. Both anomalies are visualised only by special radiological projections

A sibling risk study that shows a statistically significant increase in risk for anteromedial osteoarthritis of the knee. Anteromedial osteoarthritis is a distinct phenotype of osteoarthritis. Previous studies have shown a genetic aetiology to both hip and knee osteoarthritis. The aim of this study was to determine the sibling risk of antero-medial osteoarthritis of the knee. We conducted a retrospective cohort study of 132 probands with primary anteromedial osteoarthritis, who had undergone unicompartmental arthroplasty. Sibling were identified as having symptomatic knee problems by postal Oxford Knee Score (OKS). A positive OKS was defined as an OKS+/− 2SD of the mean of the proband group. Sibling spouses were used as controls. Those siblings & spouses that were symptomatic from the OKS were invited to undergo Knee X-rays, to look for radiological signs of osteoarthritis. Osteoarthritis was diagnosed as greater than Grade II on the Kell-gren Lawrence classification. The pattern of disease was noted and it was considered if the sibling were suitable for a unicompartmental knee arthroplasty. The prevalence and sibling risk of anteromedial osteoarthritis was determined using a randomly selected single sibling per proband family. The prevalence was determined in the 103 single proband sibling pairs. There was a statistically significant risk within the sibling group P= 0.024 using the Chi square test. The relative risk of anteromedial osteoarthritis was. 3.21(95% CI 1.08 to 9.17). Genetic factors play a major role in the development of anteromedial osteoarthritis

A prospective study was made of 119 children with transient synovitis or any other cause for synovial effusion and elevated intra-articular pressure. During a follow-up of one year not one case of Perthes' disease was diagnosed and the late clinical and radiographic changes were minimal with moderate overgrowth of the femoral head in 33% and widening of the joint space in 14.2%. Our results do not support the widely accepted concept that Perthes' disease develops as a result of the period of elevated intra-articular pressure found in transient synovitis. Further research into this and Perthes' disease should follow the premise that they are two different diseases without any aetiological connection

1. The clinical features of hyperostosis cranii are briefly reviewed. In large series of cases the syndrome has been found to occur almost entirely in females. 2. In recent studies of dystrophia myotonica, it is apparent that hyperostosis cranii is one of the variable features of the disorder. This disease occurs equally among males and females and the hyperostosis cranii also is distributed equally among males and females. 3. Hyperostosis cranii also occurs in patients with Morgagni's syndrome, with acromegaly, and as "senile hyperostosis.". 4. The etiology of hyperostosis is still a matter for speculation. More recent studies have focused attention on the endocrine system, and it seems probable, in view of the sex distribution in dystrophia myotonica, that the key to the problem may be found in this disorder. 5. In dystrophia myotonica the characteristic skull changes are hyperostosis cranii, a small pituitary fossa, excessive sinus formation and prognathism. These are acromegaloid changes. Gonadal atrophy is a common feature and endocrine study suggests that the endocrine defect is primarily a failure of the androgenic function of the adrenals and the testes. 6. In rodents and in humans ablation of the gonads leads to overactivity of gonadotrophic cells and, at times, of somatotrophic cells. Sometimes pituitary tumours develop. 7. Acromegaloid features may occur in eunuchs, and it is likely that the acromegaloid changes in dystrophia myotonica are of the same order from overactivity of growth hormone. 8. In animals excess of growth hormone produces thickening of the skull. 9. In dystrophia myotonica, acromegaly, and Morgagni's syndrome, it is suggested that hyperostosis cranii is an expression of unrestrained activity of growth hormone

Slipped upper femoral epiphysis (SUFE) is a condition, which affects the immature hip joint. Many theories have been postulated as to its underlying aetiology however; its exact cause is, as yet unknown. The final common pathway appears to be failure of the of the growth plate to resist shearing forces, giving rise to displacement of the femoral head. We hypothesized that the lubricating ability of the synovial fluid in hip joints of children with SUFE was defective, thereby allowing increasing shear forces on the physis to occur, so that when the joint is loaded it will fail at its weakest point, namely the capital epiphysis. Aim: The aim of this study was to establish a biomechanical porcine cadaveric model to study SUFE and use this model to determine how defective joint lubrication may increase the probability of SUFE. Methods: Using immature porcine femurs and a custom-made rig, a torsional load was applied about an axis perpendicular to the growth plate in order to cause the femur to fail along the growth plate. The Hounsefield testing machine applied a tensile load and recorded the associated elongation. From these figures the torque applied to the femoral head and the associated angular rotation could be computed. Using Weibel analysis we were able to determine the probability of SUFE occurring for a range of synovial fluid coefficients of friction, a range of joint reaction forces and neck-shaft angles. Results: We found that it is possible to induce a SUFE in an immature porcine loaded hip joint and that there was an increased probability of slip with increased coefficient of friction of synovial fluid, increased percentage body weight and increased neck-shaft angle. Conclusion: Defective lubrication may be a key underlying aetiological factor responsible for SUFE

Aims: The study aimed at analyzing the outcome of femoral components in patients with total hip replacement following osteonecrosis of the femoral head with regard to the associated factor of the osteonecrosis. Methods: We reviewed 41 patients with 55 cementless total hip replacements operated for advanced osteonecrosis. According to etiology of the osteonecrosis patients were divided into two groups. The first group included 17 cases with osteonecrosis without a systemic disease and the second group 38 cases with osteonecrosis associated with a systemic disease (alcohol abuse, corticosteroid medication, sickle-cell-disease). Results: The follow-up was on average 6.4 years (range, 2 to 12.8). Eight stem revisions had to be performed, all of them were in the patients with a systemic disease. Ten-year survival rates with femoral revision as the endpoint were in the first group 100%, and in the systemic disease group 68% (p=0.03). Conclusion: The data of this retrospective study supports the notion that the aetiology of osteonecrosis might has an influence on the survival of the femoral component

We report four patients who showed hundreds of brilliant white loose bodies at arthroscopy of the knee after a short history of pain and crepitus. Histological, historical and clinical evidence is presented which indicates that the aetiology of this condition is the culture of chondrocytes in synovial fluid. It is suggested that reversal of the usually accepted order of events in synovial osteochondromatosis could provide a better and unified explanation for both that condition and multiple loose bodies. The term 'snow storm knee' is proposed to describe the dramatic picture seen at arthroscopy

We have shown that stress fractures can be induced in the tibial diaphysis of an animal model by the repeated application of non-traumatic impulsive loads. The right hind limbs of 31 rabbits were loaded for three to nine weeks and changes in the bone were monitored by radiography and bone scintigraphy. The presence of stress fractures was confirmed histologically in some cases. Most animals sustained a stress fracture within six weeks and there was a positive correspondence between scintigraphic change and radiological evidence. Microscopic damage was evident at the sites of positive bone scans. The progression, location, and time of onset of stress fractures in this animal model were similar to those in clinical reports, making the model a useful one for the study of the aetiology of stress fractures

Introduction: To determine the aetiology of peripheral nerve injuries presenting to a specialist centre, identify the management strategies employed and discuss the functional outcome achieved. Methods: Retrospective review of all children referred to this hospital between 1996–2003 with an acquired nerve injury. Obstetrical brachial plexus palsy was excluded. Results: 100 nerve injuries (94 patients) were identified. The mean age was 9.9yrs (0.5–16yrs). 81 injuries involved the upper limb, 19 the lower limb. Most were due to low energy trauma and associated with fractures or their surgical management. 16% presented with autonomic sympathetic dysfunction, 10% with neuropathic pain. 43 patients underwent at least one surgical procedure. The operation was classified diagnostic in 5 (no surgically remediable lesion identified), therapeutic in 33 (surgical procedure could be expected to aid recovery) and reconstructive in 5 (no improvement in nerve function could be achieved; functional improvement achieved by other means). Excellent functional outcome only occurred in conservatively treated cases and in some treated by neurolysis. Nerve grafts and direct repairs were associated with good outcomes. Delayed surgery was associated with fair outcomes. Discussion: Peripheral nerve injuries in children as in adults require careful, prompt attention to obtain the best outcome. Iatropathic injuries must be acknowledged

Heritable thrombophilic disorders have been proposed as one of the causes for Legg-Calvé-Perthes disease. A total of 62 patients diagnosed with this disease between 1988 and 1997 and 50 controls were screened for thrombophilia. The incidence and relationship of thrombophilia to the severity of the disease were evaluated. One patient and none of the controls had protein S deficiency. One of the control group and one of the patients had protein C deficiency with the latter child also having a combined deficiency with a mutant factor V gene. The number of children with a mutant factor V gene, protein C deficiency, who were homozygous for the C 677T polymorphism of methylenetetra-hydrofolate reductase or were heterozygous for mutant G20210A prothrombin did not differ statistically in the study and the control groups. No patient had antithrombin deficiency or positive lupus anticoagulant. We found no correlation between thrombophilia and the extent of the disease. The most common risk factors for arteriovenous thromboembolism showed no statistical significance in our patients compared with the control group or with the general population. These data do not confirm an aetiological role for thrombophilia in Perthes’ disease

Introduction:. Recent studies have concluded that gender influences hip morphology at the time of surgery as well as dysplastic development of the hip. This may lead to a particular choice of implant including stem design and/or neck modularity. In this study we hypothesized that not only gender but also morphotype and etiology (primary osteoarthritis versus aseptic osteonecrosis) may be a significant factor to predict the anatomy of the hip at the time of total hip arthroplasty (THA). Methods:. We reviewed 690 patients undergoing THA for primary arthritis (OA) or avascular osteonecrosis (AVN) between April 2000 and June 2005 and stratified each into three groups based on their anatomic constitution: endomorph (EN), ectomorph (ECT), or mesomorph (ME) (determined by the ratio: pelvic width/total leg length measured on full-length X-rays). Two independent observers measured twice four parameters on preoperative CT scan: neck-shaft-angle angle (NSA), femoral offset value (FO), helitorsion (Ht) value and femoral neck anteversion (Av). Results:. No significant difference were observed between men and women for the four parameters with respectively: NSA (129.29° ± 5.6 versus 129.3° ± 5.7), Av (20.3° ± 8.6 versus 20.27° ± 8.6), FO (19.7 mm ± 3.98 versus 19.74 mm ± 3.98) and Ht (19.97° ± 12.2 for men and 19.94° ± 12.3). Significant difference were found for NSA: 130.1° ± 5.8 for ECT, 129.55° ± 6 for MES and 128.2° ± 5,1 for EN with p < 0.01. For Av, the values were: 18.9° ± 8.7 for ECT, 20.74° ± 8.1 for MES and 21.2° ± 8.95 for EN (p < 0.01). For FO the values were 19.1 mm ± 3.9 for ECT, 19.7 ± 4 for MES and and 20.44 mm ± 3.93 for EN (p < 0.01). No difference was found for Ht between the 3 groups. A significant difference was found between patients suffering from OA and AVN: mean NSA was 130.36° ± 8.79 for OA patients versus 127.35° ± 8.38 for those who had an AVN (p < 0.01). A value was 17.06° ± 8.1 for OA and 23.7 ± 7.89 for AVN (p < 0.01). FO value was 18.72 mm ± 3.71 for OA versus 20.75 mm ± 4.15 for AVN (p <0.01). And Ht was 18.94° ± 9.64 for OA and 21.05° ± 14.5 for AVN patients (p < 0.01). Discussion and conclusion:. Patients with short and wide morphotype (endomorph) had, irrespective of gender, lower values of NSA with greater anterversion and offset values, whereas patients with long and narrow morphotype (ectomorph) had higher values of NSA and smaller Av and FO (figure 1). In the same time patients suffering from AVN have lower NSA angle, lower Av, smaller FO and Ht (figure 2). Femoral stem design should allow the consideration of these differences to optimize the reconstruction of the hip at the time of THA including pre-operative and intra-operative modularity

Introduction Spondylolysis and isthmic spondylolisthesis (IS) have both a familial and mechanical aetiology, yet the phenotypic expression of the familial aetiology is unknown except for the observation of spinal bifida occulta. Other posterior element abnormalities are unrecognised, and any facet joint orientation (FJO) abnormality at the effected level has been ignored because of presumed previous mechanical defunctioning by the pars defect. The recognition of multilevel sagittal FJO in L4/5 degenerative spondylolisthesis (DS), begs the question whether more proximal segment examination may reveal FJ variations in IS. Methods MRI scans were used to measure orientation of the FJ at L3/4, L4/5, and L5/S1 in 30 individuals with normal scans, and 30 patients with IS. The angular measurement recorded is in relation to the coronal plane. Repeated measures assessment confirmed method validity. Results Mean measurement of axial FJO at L3/4 and L4/5 was 51.1 and 42.5deg in normal subjects, and 45.2 and 35.0deg in IS. The more coronal angulation at the levels above a pars defect in IS was highly statistically significant (p=0.0006 & p=0.00002). At L5/S1 orientations were the same (39deg). Discussion Relative coronal FJO in the lumbar spine may be the phenotypic expression of the congenital aetiology of IS. The mechanism of effect may be increased stress concentration at the pars between or below coronally oriented FJs. These more coronal FJOs in IS also explain:- the common observation of retrolisthesis at L4/5 above IS when the L4/5 disc degenerates, lateral overhang of the L4/5 FJ to the L5 pedicle entry-point above an IS, and the exceptionally uncommon combination of DS at L4/5 and IS at L5/S1 when both disorders are independently common. This latter observation can be further explained by the generalization that DS occurs in those individual with sagittal lumbar facets, and that IS occurs in those with more coronal FJs

To retrospectively analyze the etiology and microbiological results of synovial fluid culture, periprosthetic tissue culture and sonication fluid culture in 74 episodes of prosthetic joint infection (PJI) in 66 patients treated at the Department for Orthopaedic Surgery in 5 years period. PJI was diagnosed according to the standard definition criteria (1). Conventional microbiological methods were used together with sonication of explanted prosthesis and sonication fluid culture. The results are presented in Table 1. Acute PJI were more common in female patients (72%), whereas delayed PJI occurred in both sexes equally. Surprisingly, among acute PJI streptococcal (especially Streptococcus agalactiae) PJI were as common as Staphylococcus aureus PJI; we also observed high percentage of polymicrobial PJI (26 % among acute PJI and 30 % among delayed PJI), whereas 6/21 (28.6%) were detected by sonication fluid culture only. Preoperative synovial fluid culture identified the pathogen in 91.3% of acute PJI and in 63.2% of delayed PJI. Sonication fluid culture identified causative pathogens in 85% of acute PJI and in 95% of delayed PJI. In acute PJI 24/34 (70.6%) patient had concordant microbiological results between standard cultures and sonication fluid cultures, whereas in 4/34 (11.7%) microorganisms were detected by sonication fluid culture only and in 6/34 (17.6%)by tissue culture only. 23/40 (57.5%)patients with delayed PJI had concordant microbiological results; in 3/40 (7.5%) pathogens were detected by sonication fluid culture only. We found sonication as very useful additional method in diagnostics of PJI, especially low grade PJI. At the same time we observed high percentage of positive and concordant mcrobiological results between all three microbiological methods in patients with acute PJI

We performed electrophysiological studies on both legs of 52 children, aged from 3 months to 15 years, with idiopathic club foot. In only nine (17%) was no abnormality found. Isolated peroneal nerve damage was seen in 14 (27%). Abnormality of both peroneal and posterior tibial nerves was found in five (10%). Four patients (8%) had evidence of isolated spinal-cord dysfunction, whereas combined spinal-cord and peripheral-nerve lesions were seen in 14 (27%). Six patients (11%) had variable neurogenic electrophysiological patterns. In 13 patients in whom the studies were repeated neither progression nor improvement of the electrophysiological parameters was observed. Pathological electrophysiological findings were found in 66% of conservatively-treated patients. In the 43 patients treated surgically, all 16 with fair and poor results had pathological electrophysiological findings and 12 required further operations. Multiplicity of the pathological findings was related to the severity of the deformity of the foot; normal studies represent a good prognostic sign. Electrophysiological studies are useful in idiopathic club foot with residual deformities after conservative or operative treatment. Our findings support the theory that muscle imbalance is an aetiological factor in idiopathic club foot

To evaluate the proportion of microbial associations causing PJI, diversity of their strains and impact on treatment failure after the removal of the hip implant and insertion of a spacer. Spectrum of pathogens in 189 cases of PJI was studied retrospectively. Strains were isolated from the joint aspirates, tissue samples and removed orthopedic devices. The cohort comprised 144 cases of PJI after primary THA and 45 cases after the hip replacement revision surgery. All patients underwent first stage of two-stage revision procedure which involves the removal of a hip implant, debridement of infected periprosthetic tissues and subsequent insertion of a bone cement spacer. There were 92 males and 97 females (median age of 57 yrs). Statistical analysis of the results was performed with GraphPad Prism 6.0 (California, USA). Microbial associations were detected in 28.6% (n=54) of PJI cases. Gram-positive bacteria prevailed in both groups with mono- and polymicrobial etiology. There were 52.5% of S. aureus isolates in monomicrobial group and 25% isolates in polymicrobial group (p=0.0002). This also included 8.4 and 20.6% isolates of MRSA, respectively (p<0.0001). CNS were detected in 20.1% of mono- and 27.9% of polymicrobial infection isolates, including about 40% of MRSE in both groups. Gram-negative pathogens accounted for 25.7% of isolates in polymicrobial group and 14.1% in monomicrobial group (p=0.022). Non-fermenting bacteria prevailed among Gram-negative strains presented in associations. Acinetobacter sp. and P. aeruginosa were identified in 7.4% (p=0.043) and 5.1% (p=0.56) of polymicrobial isolates. The percentage of treatment failure after the removal of the hip implant and insertion of a spacer was considerably higher (p<0.0001) in patients with polymicrobial than monomicrobial infection: 72.2 vs 25.2%, respectively. The proportion of isolates in microbial associations involving Gram-negative pathogens was 61.5% in patients with infection recurrence and 26.7% in patients with a successful outcome of the surgery (p=0.033). Microbial associations were found in 28.6% of PJI cases after hip arthroplasty. They posed a significant risk for treatment failure after removal of the hip implant and insertion of a spacer. The multidrug-resistant strains (MRSA, Acinetobacter sp. and P. aeruginosa) were often isolated in microbial associations. Our results suggest that further study of the risk factors for polymicrobial infection is necessary in patients with PJI. Identification of a patient group at high risk for developing polymicrobial PJI will allow prescription of empiric antimicrobial therapy in time, taking into account possible multi-resistant pathogens

The purpose of this study was to investigate the role that genetics play in the aetiology and symptomatology of full thickness tears of the rotator cuff. From a retrospective, cohort study of 205 patients diagnosed with full thickness rotator cuff tears, we determined, using ultrasound, the prevalence of full thickness tears in their 129 siblings. Using 150 spouses as controls, the relative risk of full thickness rotator cuff tear in siblings v controls was 2.42 (p< 0.0001, 95 % CI 1.77 to 3.31). The relative risk of symptomatic full thickness rotator cuff tear in siblings v controls was 4.65 (p< 0.0001, 95 % CI 2.42 to 8.63). The significantly increased risk for tears in siblings implies that genetic factors play a major role in the development of full thickness tears of the rotator cuff

Femoral head necrosis in the context of high impact gymnastics of young adolescents is rare but seems a more serious complication compared to a Perthes like necrosis.

Between 2017 and 2019, three young females aged from12 to 14 years were referred due incapacitating hip pain and severe collapsing femoral head necrosis. The indication of hip preserving surgery was based on the extent of the necrosis, presence of a vital lateral pillar and joint subluxation.

In one of our 3 cases total head involvement made THR necessary, which was performed elsewhere. In the remaining 2 cases, head reduction osteotomy plus periacetabular osteotomy led to a good and a fair result.

Repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension/ external rotation could be the cause of severe femoral head necrosis in three adolescent female gymnasts we are reporting on. Supra-selective angiography or sonography may be helpful to improve indication. Targeted adaptation of training methods should be discussed. Due to the severe vascular insult, results have to be considered moderate.

Purpose: Infection after resection and total knee arthoplasty for malignant bone tumours in children is a serious complication which may compromise limb salvage. The purpose of this work was to study the aetiology, treatment and prognosis of this event. Material and methods: Among the 169 total knee arthroplasties performed for malignant bone tumours between 1981 and 1999, we selected 17 patients meeting the following criteria: proven infection with identified germ on deep samples or presence of a fistula more than two years after surgery. All of the patients had osteogenic sarcomas (excluding Ewing sarcomas which account for 30% of the tumours in this localisation). The bone tumour involved the femur (n=11) or the tibia (n=6) and required extraarticular (n=14) or transarticular (n=2) resection. Infections were primary (n=9) developing after the first operation, or secondary (n=8) to surgical revision in six, joint wound in one, or haematogeneous dissemination in one patient. The causal germ was identified in thirteen patients (76%) and was a staphylococcus in all cases. Treatment included systemic antibiotics and lavage (n=10), one-procedure change in prosthesis (n=3), removal of the implant with replacement by a spacer (n=2), surgical abstention (n=2), or amputation (n=1). Results: Mean follow-up was eight years (2 – 16 years). On the average, treatment of infection lasted 51 months and required a 3.9 surgical interventions. At last follow-up, infection was considered cured in 70% of the patients who were free of clinical or laboratory signs of infection without antibiotics for at least one year. The arthroplasty could be preserved in one-third of the cases (22% of the primary infections and 50% of the secondary infections). Another treatment, arthrodesis (n=6), Borggreve procedure (n=1), or amputation (n=4), was given in the other two-thirds. Discussion: The 10% complication rate observed here is in agreement with data in the literature. Development of primary infection is influenced more by the histology of the tumour and the presence of skin wounds (methotrexate) than by tumour site or type of resection. The diagnosis of primary infection is made late, often at the end of the postoperative chemotherapy protocol. Changing the implant is the ideal treatment. Secondary infection is characteristically less difficult to diagnose; infection is recognised earlier and the chances of preserving the implant are better

Purpose: The objective of this study was to analyze the clinical results of arthroscopic release for the treatment of shoulder stiffness and to report the results according to etiology. Method: Thirty cases were reviewed in 29 patients with a mean age of 48 years [range, 25–75]. The mean time from diagnosis to surgery was 37.5 months [range, 6–120]. The stiffness was considered idiopathic (i.e. frozen shoulder) (10 cases), post-traumatic (eight cases) or post-surgical (12 cases). The release consisted of 14 rotator interval resections, four anterior capsulotomies, 20 anterior and inferior capsulotomies, three tenotomies of the superior portion of the subscapularis, and 11 biceps tenotomies or tenodeses. In 26 cases, associated extra-articular procedures were also performed, including 22 subacromial bursectomies and four acromioplasties. Patients were reviewed at a mean follow-up of 44 months [range, 12–99]. Results: Eighty-nine percent were satisfied or very satisfied. The mean Subjective Shoulder Value was 76%. The mean Constant score increased from 40 ± 13 points preoperatively to 74 ± 16 points postoperatively (p< 0.05). Conclusion: Arthroscopic shoulder release is effective for pain relief and improved function. The recovery of motion is better in idiopathic stiffness (i.e. frozen shoulder) than in post-traumatic and post-surgical stiffness. Resection of the rotator interval seems effective to restore external rotation and elevation

1. An anatomical study of the bony structure of the pars interarticularis of the fourth and fifth lumbar vertebrae has been made in specimens from seven cadavers aged seventeen to sixty-seven. 2. Layers of cortical bone have been described antero-laterally and postero-medially which are thickest in the narrowest region of the pars. 3. In one specimen from a seventeen-year-old male, a healing fracture was found in the antero-lateral layer of cortical bone in the right neural arch of the fourth lumbar vertebra. 4. The stresses to which the pars is subject consist primarily of shear forces applied to the articular processes. The significance of these stresses to the etiology of spondylolysis is discussed

Purpose: Congenital idiopathic clubfoot is the most common musculoskeletal birth defect developing during the fetal period, but with no known etiology. MYH 2, 3, 7, and 8 are expressed embryonically or perinatally, the period during which congenital idiopathic clubfoot develops; are all components of Type II muscle, which is consistently decreased in clubfoot patients; and are associated with several muscle contracture syndromes that have associated clubfoot deformities. In this study, we hypothesized that mutations in embryonic and perinatal myosin genes could be associated with congenital idiopathic clubfoot. Methods: We screened the exons, splice sites, and predicted promoters of 24 bilateral congenital idiopathic clubfoot patients and 24 matched controls in MYH 1, 2, 3, and 8 via sequence-based analysis, and screened an additional 76 patients in each discovered SNP. Results: While many SNPs were found, none proved to be significantly associated with the phenotype of congenital idiopathic clubfoot. Also, no known mutations that cause distal arthrogryposis syndromes were found in the congenital idiopathic clubfoot patients. Conclusion: These findings demonstrate that congenital idiopathic clubfoot has a different pathophysiology than the clubfoot seen in distal arthrogryposis syndromes, and defects in myosin are most likely not directly responsible for the development of congenital clubfoot. Given the complexity of early myogenesis, many regulatory candidate genes remain that could cause defects in the hypaxial musculature that is invariably observed in congenital idiopathic clubfoot. Significance: This study further differentiates congenital idiopathic clubfoot as distinct from other complex genetic syndromes that can present with similar deformities, and thus facilitates further research to improve the clinical diagnosis and treatment of congenital idiopathic clubfoot

Object: To study the incidence, etiology and management of patients with neuralgia following Posterior Lumbar Interbody Fusion (PLIF). Design: A prospective study of 85 patients undergoing PLIF surgery from March 1996 to March 2001. Subjects: Seven of the 85 patients undergoing PLIF surgery developed new leg pain between three days and five months following surgery. Results: The incidence of neuralgia was 8%. In all the patients the post-surgical neuralgia was in a new distribution. MRI examination ruled out misplaced pedicle screws in all cases, but was otherwise unhelpful. One patient developed neuralgia five months post-operatively due to collapse of the cortico-cancellous graft and secondary foraminal narrowing. This was not relieved following surgical decompression. Four patients had neuralgia caused by relative stenosis of the exiting nerve (3) or the traversing nerve (1) which started between three days and two weeks after surgery. The pain was relieved in all four following surgical decompression. One patient had leg pain when lying down; standing and sitting relieved this. A loose lamina was found on exploring the wound. Her pain settled after surgery. One patient developed a spondylolisthesis at the level below a L4/5 PLIF four months after surgery. Her pain was eased by stabilization of the lower segment. Conclusions: MRI scans are not very helpful in these cases. Early exploration is recommended and gave good results in six of our seven cases

Object: To study the incidence, etiology and management of patients with neuralgia following Posterior Lumbar Interbody Fusion (PLIF). Design: A prospective study of 216 patients undergoing PLIF surgery from March 1996 to August 2003. Subjects: 16 of the 225 patients (7.1%) undergoing PLIF surgery developed new leg pain following surgery. Results In all patients, the distribution of the postoperative pain was different than the pre-operative pain. Nerve swelling with relative stenosis was the most common cause (9/16), followed by pedicular screw misplacement (2/16), nerve anomaly (2/16), loose posterior arch (2/16), and graft subsidence (1/16). Nine patients with nerve swelling complained of pain with no neurological findings. One responded to a root block and 6 to re-exploration and further decompression. The patients with misplaced screws woke up from surgery with pain and neurology. The pain responded to removal of screws in both. Two patients with loose posterior arches complained of leg pain while lying down only. These symptoms disappeared after excision of the arches. In 2 patients conjoint roots were found intra-operatively. Both developed post operative pain, which settled down in one. In one patient subsidence of an iliac graft caused pain a few months following surgery and did not respond to further decompression. Discussion: The overall incidence of post PLIF neuralgia was 7.1%, however by removing the whole facet, as performed in the last 122 patients, the incidence reduced from 9.7% (first 103 patients) to 4.9%. Based on our data we propose a classification system for Post PLIF Neuralgia, and a management plan. Using both, 11 of the 16 patients reported their leg pain disappeared, leaving only 5 patients with residual leg pain (< 3%). Key-stones in avoiding post PLIF neuralgia are generous decompression of the nerve roots, especially the lateral recess above the disc, total facetectomy and removal of graft pieces before closure

Aim. Paediatric fractures are common but those occurring in non-ambulant children are associated with higher rates of Non Accidental Injury (NAI). There is little published on the mechanisms of injury associated with accidental fracture in young children. This study explores the aetiology of long bone fractures in non-ambulant children. Methods. This retrospective multicentre study looked at children aged ≤18 months presenting to three hospitals over 3 years (2009 to 2011). Information was gathered on age, gender, fracture type, injury mechanism, final diagnosis, treatment and details of screening for NAI. Results. 147 children were identified who were ≤18 months old (mean 12 months). There were 32 femoral, 37 tibial, 43 forearm, 17 humeral, 16 clavicular and 3 fibular fractures. We identified 6 confirmed cases of NAI and 7 pathological fractures (osteopenia of prematurity or osteogenesis imperfecta). 5/64 children aged ≤12 months old had NAI compared with 1/83 in those aged >12 months. All 7 pathological fractures occurred in the ≤12 months group. NAI or pathological fracture was more likely in ≤12 months group compared to those >12 months (p=0.0002) Of the 12 children with no clear mechanism of injury, 5 had NAI and 3 had pathological fractures. In 39/147 children NAI was considered in the documentation and 29 had a paediatric review. Falls from beds and change mats were more common in ≤12 months group, as well as transverse femoral fractures; caused when those carrying the child slipped downstairs and applied a sudden bending force to the held leg. In those >12 months falls from chairs, down steps, in playgrounds or on trampolines were more common. 12/147 fractures were caused directly by other children (6 in each group). Conclusion. Our study identified causes of accidental long-bone fracture in non-ambulant children. In cases where there is no clear mechanism of injury, NAI must be carefully excluded

We report the presence of estrogen receptor (ER) in the ligamentum capitis femoris (LCF) and hip capsule. We took 15 LCF and hip capsule biopsies from 15 patients undergoing hip surgery for the Developmental Dysplasia of the hip (DDH) and 15 hip capsules and LCF’s from intrauterine ex fetuses. The mean age of the babies was 10.3 months (6–18 months) at the time of surgery. Total 60 specimens were grouped into two as the DDH group and the control group and each of these groups were further divided into two to generate the groups for the LCF and hip capsules. Full thickness 1 x 1 cm anterior capsule and LCF portions were taken as biopsy specimens. An immunohistochemical study using monoclonal antibody against to estrogen receptors was performed to identify estrogen target cells in the hip capsule and LCF. The positive rates of ER staining in the control group were % 1.6 ± 0.2 for the LCF and % 1.3 ± 0.2 for the hip capsule, in the DDH group positive rates of ER staining were %2.5 ± 0.3 for the LCF and % 2.0 ± 0.3 for the hip capsule. The positive rates of ER staining in LCF and hip capsule of the control group were significantly lower than that in the DDH group in both groups we found ER’s to be significantly lower in the hip capsule than in LCF. The presence of estrogen receptors in the LCF and hip capsule supports the effect of estrogen in etiology of the DDH

Purpose of the study: Among the causes of secondary congenital equinovarus club foot, neurological disorders predominate. The entity we examine here corresponds to irreversible pure motor paralysis with no sensorial disorder affecting the lateral compartment predominantly and sometimes associated with involvement of the anterior compartment. There is no literature on this entity. Beyond the question of the aetiology, the demonstration of this pathological condition can modify therapeutic strategy in order to prevent recurrence. Material and methods: We examined 42 congenital equinovarus club feet with persistent pure motor paralysis involving the lateral compartment and sometimes the anterior compartment with a mean 10 years follow-up. The Dimeglio classification was used and an analytical muscle score was noted for each patient. Complementary tests included an electromyogramme when possible. Conservative treatment was the rule either using a functional method or the Ponseti method; surgery was then proposed when necessary for posteromedial release with or without palliative muscle transfer. The following procedures were performed: posteromedial release (n=33) and muscle transfer (n=26): tibialis posterior (n=22), tibialis anterior (n=3); hemisoleus (,n=1); tibialis posterior associated with flexor digitorum longus (n=3). Results: Conservative treatment was used for all feet but all presented recurrence and required secondary surgery (33 posteromedial releases and 26 muscle transfers). Discussion: This study opens the discussion on the similarity between idiopathic and arthrogryoposis club foot since the electromyography sometimes reveals an anomaly of the anterior horn. Thus club foot with pure motor and persistent paralysis involving the lateral and/or anterior compartment will not respond sufficiently to nocturnal contention if an adapted muscle transfer is not associated. Conclusion: Muscle transfer to reactivate dorsal flexion of the foot enables a better functional outcome. First intention conservative treatment can be instituted while waiting for potential recovery. If the paralysis persists beyond one year, muscle transfer is indicated before the deformity recurs and requires an associated posteromedial release

The etiological diagnosis of the loosening of a total joint replacement is of highest importance for the prognosis of the patient and the survival of the revision. However no test proved to be definitive and reliable in making a diagnosis of a periprostetic infection or to exclude it. In this study a twofold comparison of the following generally accepted methods of periprostetic infection diagnosis was made: First, the results of intraoperative and extraoperative incubation of cultures among each other and secondly, the cultures with the preoperative levels of the two acute phase reactants CRP and ESR were compared. Within the prospective study started in the Istanbul University, Cerrahpasa Faculty of Medicine, Department of Orthopaedics and Traumatology in November 2001, CRP and ESR analyses as well as specimens of liquid, swab and biopsy cultures of 32 cases were examined until June 2002. In each case two specimens were taken intraoperative, which were incubated immediately in the operating room and afterwards in the laboratory. The statistical analyses were performed with the software SPSS for Windows, where the Mann-Whitney U test and the chi square test were applied. We had 24 female and 8 male cases. The average age was 61.44. Eight patients were found infected, the 24 other cases were aseptic. CRP and ESR, which are the most useful preoperative acute phase reactants, were found to have a sensitivity of 53.8% and 42.1% and a specificity of 94.4% and 100%, respectively. CRP and ESR measured together had a sensitivity of 58.3% and a specificity of 100%. It was concluded that the CRP levels in the infected cases were not significantly affected by an additional rheumatological disease of the patient. Three different kinds of microorganisms were found in the eight infected cases: methicillin sensitive coagulase (−) staphylococcus in four cases, methicillin sensitive staphylococcus aureus in three cases and methicillin resistant coagulase (−) staphylococcus in one case. For the specimens incubated in the operating room the reproduction and diagnostic power of the specimens isolated from the liquid was found significantly higher than the specimens isolated from the swap and the biopsy (p< 0.001). CRP and ESR are parameters helping the surgeons to make reliable preoperative decisions. As the diagnostic power of a normal level CRP and ESR combination is significantly different than a high level combination, we find it useful to require both tests before the operation. For the diagnosis and tracking of patients with additional rheumatological disease CRP should be required primarily. If the surgeon suspects any infection during the operation, first of all liquid specimens should be taken and tried to incubate them in the operation room conditions

Background: To our knowledge, there are no publications that have evaluated physical activities in relation to the etiology of AIS other than sport scoliosis (1,2) so we undertook a study to assess the physical activities of patients with progressive AIS from their first year to early teens and compared these with those of a control group. Methods: All 156 children in this study had to adhere to the following 6 criteria:- born full term, fed well as infants, achieved their milestones, no hospital visits except for sports injuries, no family history of a scoliosis and no back pain (prior to diagnosis in the patient group). We compared 79 consecutive patients (girls 66, boys 13) diagnosed as progressive AIS (62 of whom subsequently had a spinal fusion) with a control group of 77 subjects (girls 66, boys 11) of similar age, gender, race and socioeconomic status. A structured history was obtained from the mother and child of each group average time taken to obtain the history was 47 minutes. Each child was examined for toe touching and vertical symmetry of spinous processes whilst standing. The findings suggest a relation between physical activities or the lack of them and the development of progressive AIS. Results: There is a significantly increased odds of AIS in those who were introduced to a swimming pool within the first year of life (p=0.001), did not attend gymnastics/ karate classes (p=0.005), did not attend dance classes (girls only, p=0.045), did not have horse riding classes (p=0.003), did not go skating (< 0.001), and who could touch their toes (p=0.011). No association is found with playing football/hockey or regular swimming at the age of 10 years. Conclusion: Progressive AIS is positively associated with an early introduction to swimming and ability to toe touch. Spinal asymmetry was noted in the controls. AIS is negatively associated with participation in dance, skating, gymnastics/karate and horse riding classes. Is it possible that children who develop AIS have a longstanding proprioception defect which makes them less likely to participate in sporting activities? If so, by encouraging children to participate in sport might we increase their proprioception abilities and make those at risk less likely to develop spinal asymmetry which may progress to a scoliosis requiring surgical correction?

Aims

The number of revision total knee arthroplasties (TKA) that are performed is expected to increase. However, previous reports of the causes of failure after TKA are limited in that they report the causes at specific institutions, which are often dependent on referral patterns. Our aim was to report the most common indications for re-operations and revisions in a large series of posterior-stabilised TKAs undertaken at a single institution, excluding referrals from elsewhere, which may bias the causes of failure.

Introduction

Historically, US arthroplasty revision rates are based on CMS data that cannot verify initial surgery date in patients under 65 years or laterality of revision. We calculated US one-year revision rates for primary total hip replacement (THR) using a representative cohort. Reasons for revision were documented.

This study sought to determine the genetic contribution of Perthes' disease, using the world's largest twin-registry.

We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least one individual had Perthes' Disease. The DTR captures every twin pair born alive in Denmark. Those with Perthes' disease were identified using health record linkage to the Danish Morbidity Record. Probandwise concordance was calculated to describe the likelihood that any given individual had LCPD if their co-twin was also diagnosed.

There were 81 twin pairs; 10 monozygotic (MZ), 51 dizygotic (DZ), and 20 unclassified (UZ). There was no association between birth weight and being the affected co-twin. Four pairs (two dizygotic and two unclassified) were concordant for LCPD, which is greater than would be expected assuming no familial aggregation. There were no concordant MZ twin pairs. The overall probandwise concordance was 0.09 (95% CI 0.01–0.18): 0.00 for the MZ, 0.08 (95% CI 0.00–0.18) for the DZ, and 0.18 (95% 0.00–0.40) for the UZ twin pairs.

This study found evidence of familial clustering in LCPD but did not demonstrate a genetic component. The absolute risk that a co-twin of an affected individual will develop LCPD is low, even in the case of MZ twin pairs.

We report a study of 112 patients with primary anteromedial osteoarthritis of the knee and their families. Sibling risk was determined using randomly selected single siblings. Spouses were used as controls. The presence of symptomatic osteoarthritis was determined using an Oxford knee score of ≥ 29 supported by a Kellgren and Lawrence radiological score of II or greater.

Using Fisher’s exact test we found that there was a significant increased risk of anteromedial osteoarthritis (OA) relative to the control group (p = 0.031). The recurrence risk of anteromedial OA to siblings was 3.21 (95% confidence interval 1.12 to 9.27).

These findings imply that genetic factors may play a major role in the development of anteromedial OA of the knee.

Dual mobility significantly reduces the risk of prosthetic instability. This mechanical complication occurs when the prosthetic head moves out from the retentive polyethylene liner, such phenomenon called intra-prosthetic dislocation reports a ten-year incidence of 2% in the literature.

We prospectively analysed all intra-prosthetic dislocations having occurred since 1985 in our department in order to investigate patient- and implant-related risk factors.

91 intra-prosthetic dislocations occurred with NOVAE (SERF) cups in 85 patients of mean age 50.7 years. Intra-prosthetic dislocation occurred after a mean period of 8.8 years.

A PRO (SERF) stem was implanted in 56 cases and a PF (SERF) stem in 35. The stems were different from one another in their neck diameter and material: 13 mm titanium neck and 16 mm stainless steel neck respectively.

When taking both prosthetic features into account, no significant difference could be established regarding the time between implantation and dislocation.

Comparison between these two prosthetic features was performed by means of two continuous homogeneous series which included 240 patients implanted with PF stems and 382 patients with PRO stems. At a mean 15-year follow-up, the two series reported a non-statistically different intra-prosthetic dislocation rate of 4%.

In both series, young age and large diameter cups were considered predisposing factors for intra-prosthetic dislocation.

Therefore, unlike suggested by several authors, prosthetic neck material and diameter do not appear as the main predictors for intra-prosthetic dislocation which is highly promoted by patient-related features.

Introduction: The cause for Subungual Exostosis remains unknown, although relationships with trauma, infection and irritation have all been suggested. We report the case of a 23 year old female who developed this condition after Zadek’s procedure done for an in growing toe nail.

Case Report: A 23-year-old woman presented to us with an infected ingrowing great toenail of 1 month duration. An X-ray was performed to rule out osteomyelitis (Figures 1a and 2a), and the patient was put on oral antibiotics to control infection. 12 weeks later, the patient underwent a Zadek’s procedure with uneventful post op. recovery. However, 4 months later the patient came back with increasing pain and swelling in the operated toe. Clinically, there was a shiny nodule measuring 0.5 x 0.5cm over the dorso-medial aspect of the nail bed which was tender to touch, hard in consistency and appeared to be arising from the bone. X-ray’s confirmed it as Subungual Exostosis (Figures 1b and 2b). She successfully underwent excision of the tumour and was symptom free with no signs of recurrence at six-month follow up

Discussion: Our case highlights the fact that Subungual Exostosis may be triggered off by damage to the nail bed during surgeries for ingrowing toe nails and that extreme care must be taken during nail removal to avoid injury to the nail bed. This complication is more pronounced in the presence of pre-existing infection. Excision appears to be the treatment of choice and a biopsy report is always needed for confirmation before discharging the patient from the clinic.

Conclusion: Careful handling of nail bed is necessary during surgery and this unusual complication can be included when taking consent for Zadek’s procedure.

Introduction: Dislocation following total knee arthroplasty (TKA) is an unusual but dramatic post-operative complication. Previously reports involve only a few isolated cases. This study retrospectively analyzed the incidence, associated factors and treatment of dislocation following TKA.

Method: All cases of TKA dislocation since 1970, when the first TKA was done at our institution, were identified from our institutional total joint registry (31.000 TKA). The medical history and X-ray were reviewed on all cases with this diagnosis. The 58 cases identified were reviewed with particular attention to associated factors that might contribute to this problem.

Results: The overall incidence of TKA dislocation was 1.87 per 1.000 arthroplasties, with a rate of 0.93 and 6.61 for primary and revision TKA respectively. The dislocations occurred at the mean of 29.5 months (range 0 to 193). Original prosthesis designs used were posterior-stabilized (53%), cruciate retaining (31%) and rotating hinge (16%). Dislocation was associated with a history of ligament laxity in 45.6% of patients, extensor mechanism deficiency in 35.5% and TKA infection in 25.9%. The mean follow-up post dislocation was 4.8 years (range 0.1 to 20.1). Non operative treatment was used for 29 knees and resulted in 25 knees experiencing further symptomatic instability. The remaining knees were treated by surgery. Of those treated by revision TKA (N=27) only 3 complained of symptomatic instability (P< 0.001).

Conclusions: TKA dislocation is a major complication. Conservative treatment is ineffective. Revision TKA reliably yields a stable knee in 89% of cases so treated. These results emphasize the importance of proper surgical technique, careful soft tissue balancing, and adequate constraint in the prevention and treatment of this problem.

1. The hypothesis is advanced that the fundamental lesion of epiphysiolysis is a slow posterior growth migration of the head on the neck.

2. It is suggested that this is unrelated to the erect posture or to any abnormality of the growth cartilage.

3. Sitting stresses are measured and are postulated as the likely cause of the growth deviation.

4. The result of the deviation is an increase in the shear stress component; in the erect posture clinical epiphysiolysis is regarded as a simple fracture occurring in a proportion of deviated cases when the increased shear component exceeds the critical level appropriate to the individual.

5. It is suggested that this hypothesis explains the age and sex incidence, the left predominance, the reduced epiphysial angle found on the uninvolved hip and the clinical and radiological evolution of the disorder.

1. Six cases of quadriceps contracture in children are described. All were either premature or suffered severe illnesses soon after birth.

2. Some additional information is given about cases of the same condition previously published by other authors.

3. It is suggested that injections and infusions given to newborn babies are sometimes the cause of the condition.

4. Some of the therapeutic substances and measures which may be responsible are discussed. These include antibiotics, vitamin K preparations and "subcutaneous" fluid therapy.

1. Twenty-eight cases of the infantile and three cases of the adolescent type of tibia vara occurring in West Indian Negroes are reported.

2. The condition is characterised by failure of growth of the postero-medial part of the upper tibial epiphysis.

3. The deformity produced is acute varus at the upper tibia with medial torsion and eventually flexion of the diaphysis on the epiphysis.

4. These deformities are considered to be due to a vicious circle set up by considerable alteration of the lines of force on the medial portion of the upper tibial epiphysial line.

In controlled clinical studies of adult diabetics a 42% incidence of signs of Dupuytren's disease was found. The incidence was highest in the older patients with a longer history of diabetes, but was not related to the severity of the diabetes. The features of Dupuytren's disease in the diabetics has a distinctive pattern, being more severe in men than women and, compared with controls, having a radial shift towards the middle finger. The disease was mild and of benign prognosis, rarely needing operation. In a further study, 13% of patients with Dupuytren's disease were found to have a raised blood glucose level. The question is posed as to whether the biochemical disturbance causes the Dupuytren's disease or whether the pattern of inheritance predisposes to both Dupuytren's disease and diabetes.

The internal pressure of simple bone cysts was found to be slightly higher than the normal pressure of the bone marrow in the contralateral limb. The pressure within the cyst was measured during drilling with a Kirschner wire; it gradually decreased as the number of drill-holes increased. The PO2 of the cyst fluid was markedly lower than that of either venous or arterial blood measured synchronously. It is suggested that venous obstruction in the bone is the likely cause of these cysts. Seven patients with simple bone cysts were treated by the multiple drill-hole method, and the clinical outcome was excellent. Multiple drilling may prove to be the treatment of choice for simple bone cysts in the younger patient, as it presents fewer hazards than other procedures.

1. It is suggested that early weight-bearing on physiologically bowed legs in infants leads to slowing of growth of the tibia and consequent increase of the differential length between fibula and tibia.

2. Such differential growth can produce both varus and medial rotation, leading to established tibia vara or Blount's disease.

3. Stimulation of tibial growth by simple metaphysial forage can correct this deformity if performed at an early age.

A careful study of children with transient synovitis of the hip has failed to establish any connection with infection by staphylococci or streptococci, with allergy, with viral infection and with trauma.

Five knees with congenital dislocation were explored. The cruciate ligaments were found to be absent or hypoplastic. The results obtained by reconstructing an anterior cruciate ligament appear to be good. On the basis of dissections of foetal knees we believe that the cruciate ligaments are the main structures preventing an anterior dislocation of the knee in early foetal life; this deviation from the adult pattern is due to the bony configuration of the foetal knee. We therefore postulate that the basic defect in congenital dislocation of the knee is an absence or hypoplasia of the cruciate ligaments.

1. Eighty-five patients have been studied soon after a ligamentous injury at the foot or ankle. These patients were treated in one of three ways, and in fifty-six patients the results were evaluated six to fifteen months after injury.

2. It is concluded: a) that ligamentous injuries at the foot and ankle frequently produce a proprioceptive deficit affecting the muscles of the injured leg; b) that such a deficit is responsible for the symptom of "giving way" of the foot; and c) that the incidence of both the proprioceptive deficit and the symptom of "giving way" can substantially be reduced by treatment after injury with the coordination exercises described in this study.

3. The mechanism of production of the proprioceptive defect is discussed.

Aim:

To determine if patients with coronal plane deformity in the lumbar spine have a higher grade of lumbar spine subtype compared to controls.

From a retrospective, cohort study of 205 patients diagnosed with full-thickness tears of the rotator cuff, we determined, using ultrasound, the prevalence of such tears in their 129 siblings. Using 150 spouses as controls, the relative risk of full-thickness tears in siblings versus controls was 2.42 (95% CI 1.77 to 3.31). The relative risk of symptomatic full-thickness tears in siblings versus controls was 4.65 (95% CI 2.42 to 8.63).

The significantly increased risk for tears in siblings implies that genetic factors play a major role in the development of full-thickness tears of the rotator cuff.

Nonunion of the distal radius is a rare complication (0.2%) which gradually can lead to deformity, pain and dysfunction of the hand. We examined 7 patients who developed nonunion of the distal radius after surgical intervention and we try to rationalize this complication.

Our material consisted of 7 patients (2 male and 5 female) average 51 years old (31–75). Two patients with distal radial malunion, developed nonunion after corrective osteotomy. Four patients with comminuted metaphyseal radial fracture and concomitant distal ulna fracture, developed nonunion after application of an external fixator alone or in combination with internal fixation. Finally one patient with isolated fracture of the distal metaphysis developed nonunion after internal fixation. All patients after the confirmation of the nonunion and until radiological union underwent 1–3 operations. The index procedures for final union were wrist arthrodesis (1 patient) radioscapholunate fusion with excision of the distal scaphoid (2 patients) and internal fixation (4 patients). Additionally, in 6 patients a supplementary method for DRUJ asymmetry was needed.

Results were estimated after a mean follow-up of 30,8 months (1–4 years) based on radiological and clinical criteria. There were 1 excellent, 5 good and 1 fair result.

Despite the existence of predisposing factors (comminution, associated fracture of the distal ulna, metabolic disease, osteoporosis, distraction through external fixator), the contribution of the surgeon to the development of the nonunion is undeniable.

Background: We have recently observed that many of our sarcoma patients presented also with thyroid disorders. Literature data are almost unavailable on this topic.

Materials and Methods: Retrospective analysis of files of patients with sarcoma and clinically overt thyroid disorders.

Results: Out of 375 patients with soft tissue sarcomas (STS) and 235 with bone sarcoma (BS) including small blue round cell tumors (SBRC), 28 patients (4.6%) had an associated significant thyroid disorder. The types of sarcoma were mainly liposarcoma followed by malignant fibrous histiocytoma, leiomyosarcoma and bone sarcoma. The primary sites were mainly limb and trunk. The interval between the diagnosis of the thyroid disorder and the sarcoma varied between {−14} years (thyroid first) and {+16.5} years (thyroid later) with a median of {−0.2} years. Thyroid disorders included goiter, thyroiditis and carcinoma.

Conclusions: There are basic-science and clinical evidences to a possible common pathway that leads to the association between overt thyroid disorders and sarcomas of bone or soft tissues. Oncogene erbA activity is related to thyroid receptors to T3 and to development of sarcoma. Cross talk of the sarcoma oncogene and the erbA might contribute to the development of sarcoma. The thyroid hormone receptor and the highly related viral oncoprotein v-erbA are found exclusively in the nucleus as stable constituents of chromatin. It has been shown that v-erbA can block the spontaneous differentiation in erythroid cells transformed by various retroviral oncogenes. V-erbA can alter the spectrum of neoplasia induced by the v-src oncogene, which causes predominantly sarcomas and erythroblastosis in chicks. The erbA can cooperate with other oncogenes such as v-erbB or with v-fms, v-ras, and c-kit. Cooperation with v-myc may play a role in the development of rhabdomyosarcoma especially in thyroid hormone deficiency state. The possible clinical implications are the need to screen patients with sarcoma to thyroid disorders, and patients with thyroid disorders for malignant diseases.

To study the contribution of the special morphological features of lumbo-sacral spine as causes of the slipping in the spondylolisthesis, the roentgenographic measurements were performed in 47 cases of spondylolysis, 77 of spondylolisthesis and 597 of several low back pain as a control.

The transitional lumbo-sacral spine was more frequently seen in the spondylolisthesis group, but there was no d ifference between the spondylolysis and control.

The angle between the superior surface and the posterior border of the sacral vertebral body (posterior superior sacral angle) was apparently low in the spondylolisthesis, whereas no difference was noted between another groups.

In conclusion, special morphological features such as low prices of the posterior superior sacral angle is considered one of the risk factors for the cause of slipping.

We report nine cases of irreducible congenital dislocation of the knee which were treated by early operation with good results. All were resistant to conservative measures and operation was performed at an average age of nine months. The essential abnormality was a short quadriceps muscle together with subluxation of the hamstring muscles to lie anterior to the axis of knee flexion. The quadriceps tendon was lengthened by VY-plasty and in six cases additional length was gained by proximal mobilisation of the muscle. After operation all the patients were able to walk.

This is a prospective study of 105 knees in 91 patients with idiopathic osteonecrosis of the femoral condyles, with an average follow-up of five years in 101 knees. Forty-eight of the 75 patients in whom the body weight was studied were obese and four of the 33 patients in whom a densitometry study was done showed decreased bone density. Prognosis is unfavourable if the lesion is larger than five square centimetres and if its width is more than 40 per cent of that of the condyle. Of the 22 patients followed up after conservative treatment 80 per cent were satisfactory. Of the 11 knees treated by arthrotomy alone 55 per cent were satisfactory. Of the 31 knees treated by osteotomy (21 with associated arthrotomy) 87 per cent were satisfactory. Arthrotomy did not significantly improve the results of osteotomies. The ideal correction was to 10 degrees of valgus. Of the 37 knees treated with replacement 95 per cent were satisfactory, and the best results were obtained with the total-condylar prosthesis.

A review was conducted of the records of fifty-five children who were admitted to the Hospital for Sick Children in Toronto between 1955 and 1975 with a diagnosis of Volkmann's contracture in fifty-eight limbs. Ten patients had been transferred to this hospital with established ischaemia after Bryant's traction for a fractured femur; all had a very poor outcome. Thirteen other cases of Volkmann's contracture affecting the superficial posterior compartment had been treated with a fixed Thomas' splint and a Bradford frame after fractures of the femoral shaft. Supracondylar fractures of the elbow resulting in Volkmann's contracture frequently had both an arterial injury and a compartment syndrome. Most of the fifty-five children reviewed here had not had early appropriate treatment. For the past twenty-one years the frequency of Volkmann's contracture has not declined in spite of many published reports on the compartment syndrome, and the hazards of supracondylar fractures and of Bryant's traction.

One hundred normal fingers were dissected and arthrographs obtained by injection of a chromopaquegelatin mixture, allowing comparison between the radiographic and macroscopic configuration of the synovial capsule. Synovial recesses protruding from each side of every metacarpo-phalangeal joint were found in relation to the collateral ligaments and corresponding exactly with the site of radiological erosions. A group of bursae lying on the superficial aspect of collateral ligaments were also demonstrated. A rudimentary infra-articular meniscus was found. The results of examination of the insertions of the interossei showed differences from traditional descriptions.

The cause of rheumatoid deformity was suggested to be the rheumatoid process arising in the lateral recesses and lateral bursae, weakening the collateral ligaments, which give way in the directions of the deforming forces. These are derived from the long flexor tendons, which were shown to exert an ulnar and volar strain on the metacarpo-phalangeal joint of every finger during grip.

The cause of pseudarthrosis of the clavicle is obscure. Right-sidedness is an almost constant feature. We have proposed that the lesion is sometimes due to pressure upon the developing clavicle by the subclavian artery which is normally at a higher level on the right side. This may be accentuated in the presence of cervical ribs or unduly elevated first ribs, both of which we have observed in association with pseudarthrosis. We have also noted pseudarthrosis on the left side in association with dextrocardia (when the relative positions of the subclavian arteries are reversed) and in the presence of a large left cervical rib.

We have speculated upon the nature of the clavicular defect in cranio-cleido dysostosis, in which disorder the first ribs are habitually elevated. A similar mechanism may be involved.

Data was collected on 139 eligible patients a minimum of 18 months post surgery who had had 2 or more ligaments reconstructed. 63 patients were available for clinical follow up. It is the largest single surgeon series studied.

27% of injuries were high energy traffic accidents. 73% were low energy, mainly sports related. 63% of patients were delayed referrals to our unit. Of these nearly 48% had already undergone knee surgery, often more than 6 months post injury. 17% of all cases presented with failed ligament reconstructions. Of those patients followed up 19% were operated upon within 3 weeks of injury, 56% were delayed reconstructions with a mean time to surgery of 21 months and 25% were revision reconstructions. Time to follow up ranged from 18 months to 10 years.

The median KOS ADL, KOS Sports Activity and Lysholm scores for uni-cruciate surgery were all better than those for bi-cruciate surgery. All results were better for acute rather than chronic cases, which in turn were better than those for revision cases. The Tegner score showed that only acute uni-cruciate reconstructions returned to their pre-injury level.

TELOS stress radiographs demonstrated a mean post drawer of 5.9 mm side-to-side difference after reconstructions involving the PCL. IKDC grades showed 6% of knees were normal and 57% were nearly normal.

37% required further surgery, mainly to increase movement or for hardware removal. There was 1 deep infection and 2 cases of thrombosis. There were no vascular complications but 2 had transient nerve injuries.

Multi-ligament surgery can produce good functional outcomes but the knee is never normal. There is an increased risk of PCL laxity post op. Early referral to a specialist unit is suggested as delayed referral to a specialist unit potentially subjects the patient to unnecessary surgery and may affect outcome.

Background

Since 1991 to 2008 approximately 800,000 Exeter stems have been sold worldwide with 80 reported cases of fracture (neck or stem). This study aimed to determine factors predisposing to fracture.

Introduction

Postural and motor activities are the results of interactions of smaller inhibitory and larger facilitating structures of the central nervous system (CNS). In the case of dysbalance of inhibitory and facilitating structures during CNS evolution, the asymmetry of postural activities can appear. This asymmetry remains hidden in the early periods of evolution and becomes apparent in the periods of quick growth and increased hormonal and metabolic activities. Genetic and neural factors have proven to be significant in the cause of idiopathic scoliosis (IS), so we propose a neural developmental hypothesis of this disease.

Metal-on-metal (MOM) hip resurfacings release chromium and cobalt wear debris into the surrounding joint. The hip tissue taken from failed MOM hips shows specific histological features including a subsurface band-like infiltrate of macrophages with particulate inclusions, perivascular lymphocytic infiltrate and fibrin exudation. This tissue response has been called Aseptic Lymphocytic Vasculitis Associated Lesion (ALVAL).

There is a recognised carcinogenic potential associated with hexavalent chromium and epidemiological data from first generation MOM arthroplasties may suggest an increased incidence of haematological malignancy. The ALVAL type reaction includes a marked proliferation of lymphocytes in the perivascular space and thorough investigation of this lymphocytic response is warranted.

This study aims to further characterise the lymphocytic infiltrate using immunohistochemistry and to test clonality using polymerase chain reaction (PCR).

Tissues from revised all cause failed MOM hip arthroplasties (n=77) were collected and analysed initially using routine H&E staining. Those that met the diagnostic criteria of ALVAL described above (n=34) were further stained with a panel of immunohistochemical markers (CD3, CD4, CD8 (T-cell markers) and CD20 (B-cell marker)). 10 representative ALVAL cases were selected and sent for gene rearrangement studies using PCR to determine whether the lymphocytes were polyclonal or monoclonal in nature.

The analysis of the lymphocytic aggregates in ALVAL, showed a mixed population of B and T cells. Within the aggregates, there was a predominance of B cells (CD20) over T cells (CD3). Of the 10 cases which were analysed by PCR, 7 were suitable for interpretation. None of these cases showed evidence of monoclonal lymphocyte proliferation.

The carcinogenic potential of wear debris from MOM hips, particularly affecting the haematopoietic system should be investigated. This study has shown a predominantly B-lymphocyte response in tissues surrounding MOM hips which is polyclonal. Although the numbers are small, the study suggests an immune mediated response in MOM hip tissue and excludes a neoplastic proliferation.

However, long term follow up of patients with MOM hips may be prudent.

The fine structure of palmar fascia from patients with Dupuytren's contracture (DC) was compared with that from patients with carpal tunnel syndrome (CTS). In contrast to previous assumptions, the ultrastructure of fibroblasts both in vivo and in vitro from DC and CTS appeared identical, indicating that myofibroblasts are not specific to DC. The major differences between DC and CTS were: 1) a sixfold and fortyfold increase in fibroblast density in cord and nodular areas of DC compared with CTS; 2) a more disorganised pattern of collagen fibrils in DC; and 3) markedly narrowed microvessels surrounded by thickened, laminated basal laminae and proliferating fibroblasts in DC compared with CTS. To account for these morphological changes a hypothesis is presented which proposes that oxygen-free radicals cause pericytic necrosis and fibroblastic proliferation. This hypothesis provides a potential avenue for therapy of DC and other fibrotic conditions.

In a family study in which thirty-four patients with osteochondritis dissecans and eighty-six of their first-degree relatives were examined clinically and radiologically, only one relative was found to have osteochondritis dissecans. No association with other forms of osteochondritis, endocrinological abnormalities or dwarfism was found.

Neck injury of the whiplash type may lead to the cranial symptoms of the Barre-Lieou syndrome. Forty patients with this syndrome and 40 without it were investigated by a variety of imaging techniques. There was a clear correlation between root sleeve defects at C3/4 shown by special oblique myelographic views and cranial symptoms. Good results were obtained by anterior cervical discectomy and fusion at C3/4 in 21 cases. It is suggested that the syndrome may result from irritation of the sympathetic nervous supply at this level.

The results of operation for traumatic anterior dislocation of the head of the radius in eight children have been reviewed. We are satisfied on the basis of the results obtained and the outcome in one untreated patient that operative reduction is fully justified, provided that the annular ligament is reconstructed and internal fixation employed. We have not seen unilateral congenital dislocation and doubt its existence. Secondary subluxation of the distal radio-ulnar joint has been noted in an untreated patient.

1. That viruses may be involved in the causation of human tumours has long been suspected but not yet proved. The discovery that osteogenic sarcoma can be induced by viral agents in mice and hamsters makes the proposition that human sarcomas may also have a viral origin basically tenable on presently available evidence. In order to distinguish between passengers and causative agents it will probably be necessary to demonstrate antigenic cross-reactivity in tumours of similar type collected from different geographical areas, and the oncogenicity in subhuman primates of extracts containing virus from human tumours. Such information is likely to become available in the next few years.

2. The demonstration of tumour-specific immune reactions in an increasing number of patients with various forms of neoplasm, including skeletal sarcomas, and the correlation of these reactions with the clinical status of the disease sustains the hope that eventually immunotherapy may contribute to the control of cancer in man.

3. Animal experiments have revealed that the potentiation of immune responses may lead to the elimination of small foci of neoplastic cells. The role of immunotherapy in the treatment of cancer may therefore be as an adjunct to surgery, radiotherapy and chemotherapy (Alexander 1968). Once the primary tumour has been removed it may be possible to employ immunotherapeutic measures to destroy the relatively few remaining cells that give rise to late metastases; this is particularly apposite to juvenile osteosarcoma.

Of 44 patients (55 hips) with slipped upper femoral epiphysis treated from 1963 to 1989, 13 (14 hips) developed chondrolysis. Eight hips had chondrolysis at the time of presentation, all in female patients who were either coloured or black and who had moderate or severe slips. The other six hips had persistent pin penetration of the joint; in five of these the pin penetrated the anterosuperior quadrant of the head. Removal of penetrating pins resulted in improvement in pain in all six hips and in the range of movement in four. Chondrolysis did not develop in any of 11 hips with transient intraoperative pin penetration. In hips with chondrolysis maximum joint-space narrowing developed within the first year; improvement in joint space and range of movement continued for up to three years after maximal involvement. At an average follow-up of 13.3 years no patient had pain but five hips were stiff.

It has been suggested that occult infection of joint prostheses contributes to a proportion of aseptic loosening. The aims of the study were to determine the incidence of occult infection in a sample of patients undergoing revision surgery for aseptic loosening and examine the role of ultrasound sonication in its detection.

A prospective trial was conducted at Christchurch and Burwood Hospitals. At the time of revision surgery, intra-operative tissue and fluid samples were taken. The removed prosthesis was immersed in saline solution in a sterile plastic container, and then sonicated. The sonicate fluid underwent prolonged routine cultures (14 days) to increase the rate of detection of slow growing organisms. The cases were patients undergoing revision surgery for aseptic loosening or infection. The control group was comprised of patients having revision surgery for any other indication. These implants were subjected to the same protocol as the study group.

A total of 122 patients were included in the study; 54 in the Aseptic Loosening [AL] group, 15 Infections and 53 controls. There were significantly more smokers in the AL group and less smokers in the control group (p=0.04 and p=0.04 respectively). The mean age for revision in the Infection and Periprosthetic fracture groups was less than those of other groups (p=0.007 and p=0.02) respectively. There were 18 cases with positive intra-operative cultures. Eight of those were in the aseptic group (i.e. 14.8% of the group). Conventional sampling techniques were positive in 17 of 18 cultures (94%). Sonication was only positive in 10 out of the 18 cultures (56%). Sonication was concordant with the conventional sampling techniques in half of the positive cultures in the AL group and overall. The only bacteria to be isolated from sonicate cultures were Staphylococcus Aureus and Coagulase Negative Staphylococci. Diabetes Mellitus was the only risk factor to have a significant association with having a positive culture result (p=0.03). There was also a significant association with having raised pre-operative Neutrophil differential count or inflammatory markers with having a positive culture (p=0.0001). However this association was not present when the AL group was examined separately.

There was a significant rate of positive culture results in the aseptic loosening group of around 15%. Ultrasound sonication was less sensitive than current sampling techniques with no apparent added benefit. This paper does not support the hypothesis that occult infection is a significant driver of aseptic loosening.

Purpose

Anterior knee pain has been relieved by resection of the infrapatellar plica (IPP). The question is: How? The hypothesis is: the IPP acts as an intra-articular ligament, a mechanical link between the forces of knee motion, the fat pad (FP) and the distal femur, holding the FP captive through the arc of motion. Release of the IPP severs this link, allowing the highly innervated FP to move freely. This may allow any underlying pathologic process to heal.