Introduction

To evaluate career length after surgical treatment of combined ACL + medial collateral ligament (MCL) and ACL +posterolateral corner (PLC) surgeries in all elite athletes. Secondly, in a subgroup of male professional footballers to determine career length and competition level after ACL+MCL or ACL+PLC reconstructions and compare this to a cohort who underwent isolated ACL reconstruction (ACL-R) alone.

Introduction

To determine if elite athletes can return to professional sport after MCL or posterolateral (PLC) reconstruction using LARS ligaments. The secondary aims are to demonstrate the safety and efficacy of LARS by reporting sport longevity, subsequent surgeries, and complications.

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X-Linked Hypophosphataemia (XLH) is a rare, progressive, hereditary phosphate-wasting disorder characterised by excessive activity of fibroblast growth factor 23. The International XLH Registry was established to provide information on the natural history of XLH and impact of treatment on patient outcomes. The cross-sectional orthopaedic data presented are from the first interim analysis.

The XLH Registry (NCT03193476) was initiated in August 2017, aims to recruit 1,200 children and adults with XLH, and will run for 10 years. At the time of analysis (Last Patient In: 30/11/2020; Database Lock: 29/03/2021) 579 subjects diagnosed with XLH were enrolled from 81 hospital sites in 16 countries (360 (62.2%) children, 217 (37.5%) adults, and 2 subjects of unknown age).

Of subjects with retrospective clinical data available, skeletal deficits were the most frequently self-reported clinical problems for children (223/239, 93.3%) and adults (79/110, 71.8%). Retrospective fracture data were available for 183 subjects (72 children, 111 adults); 50 had a fracture (9 children, 41 adults). In children, fractures tended to occur in tibia/fibula and/or wrist; only adults reported large bone fractures. Joint conditions were noted for 46 subjects (6 children, 40 adults). For adults reporting osteoarthritis, knees (60%), hips (42.5%), and shoulders (22.5%) were the most frequently affected joints. Retrospective orthopaedic surgery data were collected for 151 subjects (52 children, 99 adults). Osteotomy was the most frequent surgery reported (n=108); joint replacements were recorded for adults only.

This is the largest set of orthopaedic data from XLH subjects collected to date. Longitudinal information collected during the 10-year Registry duration will generate real-world evidence which will help to inform clinical practice.

Authors acknowledge the contribution of all International XLH Registry Steering Committee members.

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Anterior cruciate ligament (ACL) reconstruction is commonly performed and has been for many years. Despite this, the technical details related to ACL anatomy, such as tunnel placement, are still a topic for debate. In this paper, we introduce the flat ribbon concept of the anatomy of the ACL, and its relevance to clinical practice.

Cite this article: Bone Joint J 2016;98-B:1020–6.

There have been differing descriptions of the anterolateral structures of the knee, and not all have been named or described clearly. The aim of this study was to provide a clear anatomical interpretation of these structures. We dissected 40 fresh-frozen cadaveric knees to view the relevant anatomy and identified a consistent structure in 33 knees (83%); we termed this the anterolateral ligament of the knee. This structure passes antero-distally from an attachment proximal and posterior to the lateral femoral epicondyle to the margin of the lateral tibial plateau, approximately midway between Gerdy’s tubercle and the head of the fibula. The ligament is superficial to the lateral (fibular) collateral ligament proximally, from which it is distinct, and separate from the capsule of the knee. In the eight knees in which it was measured, we observed that the ligament was isometric from 0° to 60° of flexion of the knee, then slackened when the knee flexed further to 90° and was lengthened by imposing tibial internal rotation.

Cite this article: Bone Joint J 2014;96-B:325–31.

Introduction:

Wear debris from articulating joint implants is inevitable. Small debris particles are phagocytosed by macrophages. Larger particles initiate the fusion of many macrophages into multi-nucleated giant cells for particle encasement. Macrophages are recruited into inflamed tissues from the circulating monocyte population. Approximately 10% of white blood cells are monocytes which after release from the bone marrow circulate for 2–3 days, before being recruited into tissues as inflammatory macrophages or undergoing apoptosis. Circulating MRP8/14 (S100A8/A9) is a measure of monocyte recruitment, part of the monocyte-endothelial docking complex, and shed during monocyte transmigration across the endothelium. The higher the S100A8/A9 the more monocytes being recruited giving an indirect measure of debris production.

Introduction:

The risk factors for degenerative joint disease are well established: increasing age, obesity, joint abnormalities, trauma and overuse, together with female gender, ethnic and genetic factors. That obesity is a significant risk factor for developing osteoarthritis in non-weight-bearing as well as weight-bearing and joints was one of the first indications that the risk was nor purely that of aberrant biomechanical loading. Low grade chronic systemic inflammation is a component of each of ageing and obesity, atherosclerosis and diabetes, culminating in Metabolic Syndrome. In our study of 1684 patients with joint degeneration 85% were overweight or obese and 65% older than 65 years with 62% being both, 73% of patients were taking medications for serious, ‘non-orthopaedic’ health problems such as cardiovascular or respiratory disease, obesity or NIDDM. Monocytes are a major component of chronic inflammation, approximately 10% of white blood cells are monocytes which circulate for 2–3 days, before being recruited into tissues as inflammatory macrophages or undergoing apoptosis. Circulating S100A8/A9 (MRP8/14) is a measure of monocyte recruitment being shed during monocyte transmigration across the endothelium. The higher the S100A8/A9 the more monocytes being recruited giving an indirect measure of chronic inflammatory status.

To date, there are no clear guidelines from the National Institute of Clinical Excellence or the British Orthopaedic Association regarding the use of Autologous Blood Transfusion (ABT) drains after elective primary Total Knee Replacement (TKR). There is little evidence to comparing specifically the use of ABT drains versus no drain. The majority of local practice is based on current evidence and personal surgical experience.

We aim to assess whether the use of ABT drains effects the haemoglobin level at day 1 post-operation and thus alter the requirement for allogenic blood transfusion. In addition we aim to establish whether ABT drains reduce post-operative infection risk and length of hospital stay.

Forty-two patients undergoing elective primary TKR in West London between September 2011 and December 2011 were evaluated pre- and post-operatively. Patient records were scrutinised. The patient population was divided into those who received no drain post-operatively and those with an ABT drain where fluid was suctioned out of the knee in a closed system, filtered in a separate compartment and re-transfused into the patient.

Twenty-six patients had ABT drains and 4 (15.4%) required an allogenic blood transfusion post-operatively. Sixteen patients received no drain and 5 (31.3%) required allogenic blood. There was no statistical difference between these two groups (p=0.22). There was no statistical difference (p=0.75) in the average day 1 haemoglobin drop between the ABT drain and no drain groups with haemoglobin drops of 2.80 and 2.91 respectively. There was no statistical difference in the length of hospital stay between the 2 groups (p=0.35). There was no statistical difference (p=0.26) in infection rates between the 2 groups (2 in ABT drains Vs. 0 in no drains). Of the 2 patients who experienced complications one had cellulitis and the other had an infected haematoma, which was subsequently washed out.

The results identify little benefit in using ABT drains to reduce the requirement for allogenic blood transfusion in the post-operative period following TKR. However, due to small patient numbers transfusion rates of 31.3% in the ABT drain group Vs. 15.4% in the no drain group cannot be ignored. Therefore further studies including larger patient numbers with power calculations are required before a true observation can be identified.

BACKGROUND

Reverse total shoulder arthroplasty (RTSA) provides an alternative to standard total shoulder arthroplasty in the treatment of selected complex shoulder problems including failed shoulder replacements. The purpose of this report is to present outcome of RTSA using Comprehensive Reverse System (CRS) as either primary or revision treatment choice.

Introduction

Austin Moore cervicocephalic prostheses have been a therapeutical option for femoral neck fractures in patients with a reduced general condition for many years. Since treatments other than total hip arthroplasties have also been included in National arthroplasty registers during the last decade, adequate reference data for comparative analyses have recently become available.

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.

The key factors in Tissue Engineering are multipotent stem cells, growth factors (necessary to manipulate cell destiny) and scaffolds (3D constructs which support the growing tissue). Mesenchymal stem cells are the most important part of this equation, and it is procurement and manipulation of these that lies at the heart of tissue engineering. Luckily, mensenchymal stem cells can be obtained from many tissues, including synovium, bone marrow and periosteum. The use of bioreactors to optimise culture conditions and improve cell viability provides an opportunity to control stem cell destiny.

Various Tissue Engineering strategies exist: manipulating cells in situ with osteogenic growth factors, such as BMP; implanting whole tissue grafts; and the use of Gene therapy. The tissues that concern orthopaedic surgeons are very diverse and no single tissue engineered construct will be able to fulfil all our clinical needs. Tissue engineering of articular cartilage is very difficult technically, but once accomplished will revolutionalise practice. The challenge lies in being able to produce cartilage as similar to native hyaline cartilage as possible.

Although promising, ACI, using culture expanded cells, is able at best to produce hyaline-like cartilage but not the real thing. Multipotent mesenchymal stem cells are being used in this field. Even simply injecting these intraarticularly has been shown to retard the progression of OA in animal models. When attempting to regenerate meniscal cartilage, the mechanical properties of the scaffold become crucial, as the biomechanics of the knee are highly hostile. Ligaments and tendons, though the least complex tissues architecturally, have very high tensile properties which will be hard to replicate.

The challenging aspects of Orthopaedic Tissue Engineering are manifold, yet the field itself is growing in leaps and bounds. Despite some initial setbacks, the new developments in this discipline are very encouraging.

Background: Implant fractures are complications that have a great impact on the patient’s quality of life after total hip arthroplasty. Nevertheless their occurrence is often considered as rare in clinical practice. We compared incidences of implant fractures in various datasets in order to calculate the risk of a fracture and assess the quality of these datasets for such evaluations.

Methods: In a structured literature analysis based on a standardised methodology the incidence of reoperations was evaluated comparing clinical studies published in Medline-listed journals and annual reports of National Arthroplasty Registers worldwide. Case reports and experimental studies were not considered.

Results: The majority of clinical studies are monocentre trials. The publications comprise a cumulative number of 72,571 stems with 234 stem fractures, 73,743 cups with 191 component fractures, and 16,381 ceramic heads with 44 fractures. A survey among the members of the American Association of Hip and Knee Surgeons covered 64,483 primary operations, hence including a similar number of primary cases as all monocentre studies together. This dataset involves 355 implant fractures.

By contrast, worldwide Register data refer to 733,000 primary operations, i.e. approximately 10 times as many as sample-based datasets.

In general, sample-based datasets present higher revision rates than register data. The deviations are high, with a maximum factor of 64 for hip stems. Whereas the AAHKS survey exhibits lower deviations than the monocentre trials, they are still too high for this data collection tool being considered as reliable and safe to provide valid data for general conclusions.

The incidence of implant fractures after total hip arthroplasty in pooled worldwide arthroplasty register datasets is 304 fractures per 100.000 implants. In other words, one out of 323 patients has to undergo revision surgery due to an implant fracture after THA in their lifetime.

Conclusion: For general assessments in the context of implant fractures, register data have the highest value. Clinical studies, which often focus on a particular implant, are of very limited value for global conclusions. Structured surveys produce more reliable data than clinical studies and are superior to monocentre trials. However, the AAHKS survey presents data that also show considerable differences to data from registers.

For the detection of rare, but severe complications like implant fractures sample-based studies achieve the goal of providing accurate figures only to a very limited extent, even if the samples are large. Here, too, comprehensive national arthroplasty registers are the most suitable tool to identify such incidents and calculate reliable figures.

Contrary to the prevalent opinion, implant fractures still are a relevant problem in arthroplasty.

Mortality after hip fractures in the elderly is one of the most important patient outcome measures. Sub-clinical thyroid dysfunction is common in the elderly population. This is a prospective study of 131 elderly patients with a mean (SD) age of 82.0 (8.9) years (range: 61–94) admitted consecutively to our trauma unit. The aim of the study was to determine the prevalence of sub-clinical thyroid dysfunction in an elderly cohort of patients with hip fracture and to determine if this affects the one year mortality.

There were three times more women (n=100) than men (n=31) in this cohort. All patients underwent surgical treatment for the hip fracture. The prevalence of sub-clinical hypothyroidism (TSH > 5.5 mU/L) was15% (n=20) and of sub-clinical hyperthyroidism (TSH < 0.35 mU/L) was 3% (n=4). Overall 18% (n=24) of patients had a subclinical thyroid dysfunction. The twelve month mortality was 27% (n=36).

Age, gender, heart rate at admission, pre-existing Coronary Heart Disease, ASA grade and presence of overt or subclinical thyroid dysfunction were analysed for association with twelve month mortality using a forward stepwise logistic regression analysis. Only ASA grade was found to significantly affect mortality at twelve months (c2 = 3.98, df = 1, p =.046). The presence of sub-clinical hypo or hyper – thyroidism was not associated with a higher mortality (p = 0.278).

We conclude that sub-clinical thyroid dysfunction does not affect the one year mortality in elderly patients treated surgically for hip fracture.

Introduction: Clinical follow-up studies are sample based, in contrast to arthroplasty register data, which refer to the entire population treated. Aim of this study is to assess the differences in revision rate to quantify bias-factors in published literature.

Materials and Methods: A structured literature review of Medline-listed peer reviewed journals on examples has been performed concerning implants with sufficient material in both data sources available. Products with inferior outcome were subsumed in a subgroup.

Results: The number of cases presented in peer reviewed journals are relatively low in general and show a high variability.

The average revision rate in peer reviewed literature is significantly lower than in arthroplasty register data-sets.

Studies published by the inventor of an implant tend to show superior outcome compared to independent publications and Arthroplasty Register data. Factors of 4 to more than 10 have been found, which has a significant impact for the results of Metaanalyses.

When an implant is taken from the market or replaced by a successor there is a significant decrease in publications, which limits the detection of failure mechanisms such as PE wear or insufficient locking mechanisms.

The final statement made about the product under investigation seem to follow a certain mainstream.

Discussion and Conclusion: Arthroplasty Register datasets are superior to Metaanalyses of peer reviewed literature concerning revision rate and the detection of failure mechanisms. Combined reviews could reduce bias factors and thereby raise the quality of reports.

Introduction: Clinical follow-up studies are sample based, in contrast to arthroplasty register data, which refer to the entire population treated. Aim of this study is to assess the differences in revision rate to quantify bias-factors in published literature.

Materials and Methods: A structured literature review of Medline-listed peer reviewed journals concerning the STAR Total Ankle Replacement have been conducted.

The published results from clinical follow up studies have been compared to Arthroplasty register Results: Results: 24% of all papers were published by the inventor of the implant.

These publications show a 3,4 times lower revision rate compared to independent studies and a 4,6 times lower revision rate compared to Register based publications.

The cumulative revision rate per 100 observed component years of register based publications is 1,36 times higher compared to independent clinical studies. The difference is statistically not significant.

Pooling the published data from all follow up studies the impact of the studies published by the inventor leads to a statistically significant bias.

Discussion and Conclusion: Publications by the inventor of the implant are overrepresented in peer reviewed scientific journals. This bias has a statistically significant impact on the final result of a Metaanalyses.

Arthroplasty Register data are able to detect bias factors and lead to a better quality of assessments concerning the outcome of arthroplasty.

Most injuries to the medial collateral ligament (MCL) heal well after conservative treatment. We have identified a subgroup of injuries to the deep portion of the MCL which is refractory to conservative treatment and causes persistant symptoms. They usually occur in high-level football players and may require surgical repair.

We describe a consecutive series of 17 men with a mean age of 29 years (18 to 44) who were all engaged in high levels of sport. Following a minor injury to the MCL there was persistent tenderness at the site of the proximal attachment of the deep MCL. It could be precipitated by rapid external rotation at the knee by clinical testing or during sport. The mean time from injury to presentation was 23.6 weeks (10 to 79) and none of the patients had responded to conservative treatment. The surgical finding was a failure of healing of a tear of the deep MCL at its femoral origin which could be repaired. After a period of postoperative protective bracing and subsequent rehabilitation the outcome was good. All the patients returned to their sports and remained asymptomatic at a mean of 48 weeks (28 to 60) post-operatively.

Recognition of this subgroup is important since the clinical features, the course of recovery and surgical requirement differ from those of most injuries to the MCL.

Purpose: Lateral meniscectomy is thought to confer a less optimal prognosis compared to medial meniscectomy however little information exists on the effect on elite sportsmen in the context of career performance and sporting ability.

Study type: Retrospective case study.

Methods: 61 international or premiership level sportsmen (36 Football, 22 Rugby, 3 Cricket) who had no previous significant knee surgery, received either medial or lateral partial meniscectomy by a single surgeon. Their subsequent career performance was analysed over a 1 to 5 year follow-up period to highlight differences in their recovery and maintenance of an elite sporting career.

Results: From our cohort 96% of sportsmen from the medial meniscectomy group were able to return to professional sports, compared to 88% in the lateral meniscectomy group. The average time to return to sports was 3.5 weeks in the medial meniscectomy group compared to 8 weeks in the lateral meniscectomy group. A statistically significant decrease in performance was noted in the lateral group, whereby 14 of the 36 sportsmen subsequently played in lower level leagues, or suffered premature retirement compared to only 1 sportsmen out of the 25 sportsmen who received a medial meniscectomy.

Conclusions: The majority of elite sportsmen who undergo partial meniscectomy are able to return to high level sporting activities and maintain their career. Unfortunately, sportsmen who undergo Lateral meniscectomy are at higher risk of not returning to their previous performance. If they do return to sport they are more likely to have diminished performance compared to those who have a medial meniscectomy. Lateral meniscectomy is associated with a relatively unpredictable recovery time-frame and higher risk of premature retirement. Athletes should be warned of these findings when treatment decisions are made.

Background: ASPS is a rare, high grade sarcoma primarily affecting children and young adults. Its origin remains enigmatic and there has until recently been no diagnostic markers. Diagnostic problems particularly occur when presenting as metastasis before detection of the primary tumour and when there is morphologic overlap with other malignancies. Recently, identification ASPS/TFE3 fusion transcripts and immuno-detection of TFE3 have been reported as useful diagnostic tools.

Design: 17 ASPS were analysed in terms of clinicopatho-logic characteristics, treatment and follow up. Archival formalin-fixed and paraffin embedded tissues were used for TFE3 immuno-histochemistry and RNA extraction followed by RT-PCR analysis and sequencing. Novel primers to detect ASPS/TFE3 fusion transcripts, type 1 and 2, were designed.

Results: The patients, 9 females/8 males, ranged in age from 3 to 46 years (median 23 years); 16 involved the extremities (9 lower, 7 upper) and one the pelvis. All but one patient had primary, curative surgery; chemotherapy and radiotherapy was given for metastatic disease. Five had lung metastases at diagnosis and 3 developed lung and brain metastases later. Four patients died of disease (after 1–5 years), 4 are alive with metastases and 9 are alive and well (after 6 mos.-10 years). 15/15 ASPS showed ASPL/TFE3 fusion transcripts (8 type 1, 7 type 2) and TFE3 immuno-positivity. Of 26 control tumours, several of which with overlapping morphologic features, none had fusion transcripts, 4 showed immuno-positivity (all granular cell tumours).

Conclusions: Immuno-detection of TFE3 and RT-PCR based identification of ASPL/TFE3 fusion transcripts in formalin-fixed/paraffin embedded tissues are powerful tools in the diagnosis of ASPS.

Background and purpose: Implantation of the femoral component at 10 to 15 degrees of anteversion is recommended in total hip arthroplasty. Surgical guidelines suggest that the lower leg be positioned horizontally or vertically with the knee flexed to 90° (figure of four). By constructing a perpendicular axis (a “figure-of-four” axis) to the lower leg, anteversion of the stem is approximated. This study was performed to validate the figure-of-four axis as a reliable intraoperative tool to approximate the retrocondylar line as reference for stem version.

Method: In 21 cadavers placed supine on an operating table, the lower legs were aligned to the horizontal plane. Using a box column drill, Steinmann nails were inserted perpendicular to the lower leg into the medial epicondyles. The Steinmann nails were replaced by cannulated titanium screws, representing the figure-of-four axis. The femoral neck axes, retrocondylar lines and the figure-of-four axes were determined using CT images of the specimen.

Results: The median version of the femoral neck axis was anteversion of 9.8° (IQR 4.5°–15.1°). The median figure-of-four axis showed a deviation of 0.5° (IQR −2.1°−2°) in relation to the retrocondylar line, whereas the median difference of the axis in relation to the femoral neck axis was 9.5° (IQR −13.6° – −2.1°).

Interpretation: The figure-of-four axis, being nearly parallel to the retrocondylar line, is a valid indirect method to determine stem version intraoperatively in patients without varus/valgus deviations of the knee.

Purposes of Study: To establish what happens, over time, to an ACL graft which is implanted in the skeletally immature knee.

Methods/Results: 5 cases of hamstring ACL reconstruction in prepubertal patients were available from the practices of 2 surgeons in which there were X-ray/MRI images taken over a period of an average of approximately 3 years from the operation. The changes in graft dimensions were measured from these images. No case of growth arrest was seen, nor of soft tissue contracture such as fixed flexion. All patients recovered to their same pre-injury level of activity, including elite level sport in 3 cases. Clinical laxity tests were always satisfactory but the senior authors have noticed that they tighten in time.

The growth of the patients was an average 17cm. The graft diameters did not change despite large changes in graft length (average 145%). Most of the length gain was in the femur.

Conclusion: Much has been written regarding potential harm to the growth plate in these patients but we are not aware of literature on the subject of the fate of the graft itself. Considerable length changes in the grafts were evident. The biological phenomena taking place in the graft are unknown. We have clearly shown an increase in the size of graft tissue due to lengthening but no change in girth. Either the graft stretches or tissue neogenesis occurs, or both. If it simply stretched then the graft would be expected to become narrower, at least in places- it did not. Nevertheless the ‘tightening’ phenomenon reported anecdotally could be due to the graft having to stretch but failing to keep up with growth. As the volume of graft increases so much then at least some neogenesis is highly likely.

Purpose of Study: To further study a group of patients with characteristic features presenting with significant, perisistent, and seemingly hard to diagnose and so treat, knee pain.

Methods/Results: 16 cases were collected. The was no association with age. 8 cases were sent as a second opinion.

Causation: 7 cases:direct trauma [5: associated with MCL tears (1 chronic overload from triple-jump),1:a blow to front of knee, 1:chronic from kneeling]

In all cases the time to make the diagnosis was prolonged. All had pain, which on close questioning was ‘neuritic’ [burning] in approximately 2/3. It was exceedingly well localized in all. Altered sensation in the appropriate distribution was noted by the patient in 3 cases, but shown in 5 cases on examination. A positive Tinel test was present in all cases.

In approximately half of cases ultrasound plus diagnostic injection of local anaesthetic [+/− steroid] was useful. However 15 of the 16 came to surgery in which a neurolysis or removal of neuroma, in 3 cases, [all confirmed on histology] was undertaken plus the underlying causative factor dealt with eg excision of osteophyte or scar. One case settled [90% better according to patient] after ultrasound-guided injection of a prepatellar bursa which was irritating the infrapatellar branch of the nerve. Of the 15 who had had surgery 12 had complete resolution of symptoms.

Conclusion: Although a relatively uncommon this scenario is worth considering as a cause of significant morbidity, with a good outcome from treatment in most cases. The presentation is of persistent very well localized troubling pain with marked tenderness, and a positive Tinel test.

Rheumatoid arthritis (RA) is a systemic autoimmune disease affecting 350,000 people in the UK. Within synovial joints, synoviocytes form a destructive pannus that degrades articular cartilage and bone. Synovial fluid glutamate levels increase 54 fold in RA patients and are also elevated in animal models of inflammatory and osteoarthritis. To determine whether elevated glutamate levels contribute to RA pathology we investigated which synovial joint tissues express glutamate receptors and whether glutamate stimulation influences synovio-cyte phenotype.

Various glutamate receptor mRNAs (NMDAR1, KA1, AMPAGluR2, AMPA GluR3, mGluR4) were expressed in tissues of the rat knee. All receptors were expressed in the patella. The fibrocartilagenous menis-cus and articular cartilage chondrocytes expressed mGluR4 and both AMPA receptor subunits. Human synoviocytes expressed NMDAR1 and KA1 mRNA.

To determine whether glutamate receptors were functional in human synoviocytes, cells were preloaded with a fluorescent indicator of intracellular calcium (iCa 2+) and stimulated with glutamate or specific agonists (NMDA or kainate, 500mM). Glutamate stimulated release of iCa2+ in 25% of synoviocytes whereas NMDA and Kainate each stimulated 15% of cells. NMDA responses increased to 57% in the absence of Mg2+ consistent with the inhibitory effect of Mg2+ on this receptor.

To determine whether activation of glutamate receptors can influence human synoviocyte phenotype, we cultured synoviocytes in various glutamate concentrations (50mM to 2mM) and measured effects of glutamate receptor antagonists on release of a proinflammatory cytokine (IL-6) and degradative enzymes (MMP2 and 9). In some RA patients, glutamate stimulation increased synoviocyte pro MMP-2 release. TIMP1 and TIMP2 release were not affected by glutamate stimulation or co-treatment with receptor antagonists.

IL-6 expression varied greatly in human synoviocytes derived from different RA patients (0–120pg/ml media). However, the AMPA/KA receptor antagonist NBQX significantly reduced IL-6 release at all glutamate concentrations. This inhibition was greater than that by CFM2 (AMPAR antagonist), indicating that activation of kainate receptors in human synoviocytes may induce IL-6 release.

We conclude that glutamate receptors are functional in human synoviocytes and regulate release of MMP-2 and IL-6 Thus glutamatergic signalling may contribute to RA pathology and represent a new therapeutic target.

The potential harm to the growth plate following reconstruction of the anterior cruciate ligament in skeletally-immature patients is well documented, but we are not aware of literature on the subject of the fate of the graft itself. We have reviewed five adolescent males who underwent reconstruction of the ligament with four-strand hamstring grafts using MR images taken at a mean of 34.6 months (18 to 58) from the time of operation. The changes in dimension of the graft were measured and compared with those taken at the original operation. No growth arrest was seen on radiological or clinical measurement of leg-length discrepancy, nor was there any soft-tissue contracture. All the patients regained their pre-injury level of activity, including elite-level sport in three. The patients grew by a mean of 17.3 cm (14 to 24). The diameter of the grafts did not change despite large increases in length (mean 42%; 33% to 57%). Most of the gain in length was on the femoral side. Large changes in the length of the grafts were seen.

There is a considerable increase in the size of the graft, so some neogenesis must occur; the graft must grow.

Purpose: The relationship of pattern of injury to this region of the knee to the intraoperative finding of abnormal common peroneal nerve position and associated nerve palsy was studied.

Methods: 54 consecutive patients with posterolateral corner disruption requiring surgery were assessed prospectively by MRI, arthroscopic examination, and by operative display. The pattern of disruption, the status of the biceps tendon and any displacement of the common peroneal nerve were recorded.

Results: Of the 54 cases, there were 9 with CPN palsy, 18 were seen to have distal injuries (13 suffering a fibular head avulsion fracture and 5 biceps tendon avulsion with no fracture). There was a strong relationship (p< 0.001) between such distal posterolateral corner injury and abnormal position of the common peroneal nerve, as 16 of the 18 (90%) patients were seen to have abnormal nerve position. No proximal injury resulted in abnormal nerve position and only 1 was associated with CPN palsy. 7 of the 13 cases of fibular head fracture had CPN palsy, and 1 of the 5 distal soft tissue avulsions.

Conclusion: There is a strong association of distal soft tissue avulsion and fibular head fracture and CPN palsy in these injuries. Whenever such a distal injury is suspected, the surgeon operating in this region should expect an abnormal position of the common peroneal nerve and appreciate the increased risk of iatrogenic damage. Presumably since the CPN is intimately bound to the biceps tendon by deep fascia, proximal retraction of the biceps tendon results in displacement of the CPN to an abnormal position and accounts for the high incidence of nerve palsy.

Introduction and Aims: To assess the tibiofemoral kinematics of the PCL deficient knee using vertical open-access ‘dynamic’ MRI.

Method: Tibiofemoral motion was assessed using open-access MRI, weight-bearing in a squat, through the arc of flexion from zero to 90 degrees in six patients with isolated rupture of the PCL in one knee [diagnosed from conventional MRI scanning and clinical assessment] and a normal contralateral knee. Mid-medial and mid-lateral sagittal images were analysed in all chosen positions of flexion in both knees to assess the relative tibiofemoral relationships. Passive sagittal laxity was assessed by performing the posterior and anterior drawer tests, while the knees were scanned, again using the same MRI scanner. The tibiofemoral positions during this stress MRI examination was measured from mid-medial and mid-lateral sagittal images of the knees.

Results: Rupture of the PCL leads to an increase in passive sagittal laxity in the medial compartment of the knee [P< 0.006]. In the weight-bearing scans, PCL rupture alters the kinematics of the knee with persistent posterior subluxation of the medial tibia so that the femoral condyle rides up the anterior upslope of the medial tibial plateau. This ‘fixed’ subluxation was observed throughout the extension-flexion arc being statistically significant at all flexion angles (P< 0.018 at 0°, P< 0.013 at 20°, P< 0.014 at 45°, P< 0.004 at 90°). The kinematics of the lateral compartment were not altered by PCL rupture to a statistically significant degree. The posterior drawer test showed increased laxity in the medial compartment.

Conclusion: PCL rupture alters the kinematics of the medial compartment of the knee resulting in ‘fixed’ anterior subluxation of the medial femoral condyle [posterior subluxation of the medial tibial condyle]. This study helps to explain the observation of increased incidence of osteoarthritis in the medial compartment and specifically femoral condyle, in PCL deficient knees.

Study Design: To design and test a new questionnaire to assess depression and other mood states.

Summary of Background Data: Measurement of depression and of other mood states in pain patients has been criticised in recent years on the grounds that most questionnaires were not developed in pain populations and suffer from criterion contamination by somatic items. In addition, there is no accepted measurement for positive emotions which are more than the absence of depression.

Objective: To develop a reliable and brief tool to assess mood in pain patients.

Method: Non-somatic items concerning depression, anxiety and positive outlook were extracted using exploratory factor analysis from commonly used instruments (Beck Depression Inventory and Hospital Anxiety and Depression Scale) completed by over 900 chronic pain patients. Confirmatory factor analysis was used to test the internal structure of the final item set. Items were then reworded and presented as a new questionnaire (the Depression, Anxiety and Positive Outlook Scale: DAPOS) to two new samples: patients attending pain management and patients attending osteopathy. The new questionnaire was compared with several well-known questionnaires (SF-36, BDI, PCS). The structure was calibrated and tested using confirmatory factor analysis on both samples. Finally, a sub-set of patients carried out a sorting task to test for face validity.

Results and conclusion: The DAPOS performed well, indicating that it is a reliable measure of the three mood states with good initial evidence of validity in these samples.

We reviewed the relationship between the pattern of damage to the posterolateral corner of the knee and the position of the common peroneal nerve in 54 consecutive patients with posterolateral corner disruption requiring surgery. We found that 16 of the 18 patients with biceps avulsions or avulsion-fracture of the fibular head had a displaced common peroneal nerve. The nerve was pulled anteriorly with the biceps tendon. None of the 34 proximal injuries resulted in an abnormal nerve position.

Whenever bone or soft-tissue avulsion from the fibular head is suspected, the surgeon should expect an abnormal position of the common peroneal nerve and appreciate the increased risk of iatrogenic damage.

MRI studies of the knee were performed at intervals between full extension and 120° of flexion in six cadavers and also non-weight-bearing and weight-bearing in five volunteers. At each interval sagittal images were obtained through both compartments on which the position of the femoral condyle, identified by the centre of its posterior circular surface which is termed the flexion facet centre (FFC), and the point of closest approximation between the femoral and tibial subchondral plates, the contact point (CP), were identified relative to the posterior tibial cortex.

The movements of the CP and FFC were essentially the same in the three groups but in all three the medial differed from the lateral compartment and the movement of the FFC differed from that of the CP. Medially from 30° to 120° the FFC and CP coincided and did not move anteroposteriorly. From 30° to 0° the anteroposterior position of the FFC remained unchanged but the CP moved forwards by about 15 mm. Laterally, the FFC and the CP moved backwards together by about 15 mm from 20° to 120°. From 20° to full extension both the FFC and CP moved forwards, but the latter moved more than the former. The differences between the movements of the FFC and the CP could be explained by the sagittal shapes of the bones, especially anteriorly.

The term ‘roll-back’ can be applied to solid bodies, e.g. the condyles, but not to areas. The lateral femoral condyle does roll-back with flexion but the medial does not, i.e. the femur rotates externally around a medial centre. By contrast, both the medial and lateral contact points move back, roughly in parallel, from 0° to 120° but they cannot ‘roll’.

Femoral roll-back with flexion, usually imagined as backward rolling of both condyles, does not occur.

The posterior cruciate ligament (PCL) was imaged by MRI throughout flexion in neutral tibial rotation in six cadaver knees, which were also dissected, and in 20 unloaded and 13 loaded living (squatting) knees. The appearance of the ligament was the same in all three groups. In extension the ligament is curved concave-forwards. It is straight, fully out-to-length and approaching vertical from 60° to 120°, and curves convex-forwards over the roof of the intercondylar notch in full flexion. Throughout flexion the length of the ligament does not change, but the separations of its attachments do.

We conclude that the PCL is not loaded in the unloaded cadaver knee and therefore, since its appearance in all three groups is the same, that it is also unloaded in the living knee during flexion. The posterior fibres may be an exception in hyperextension, probably being loaded either because of posterior femoral lift-off or because of the forward curvature of the PCL. These conclusions relate only to everyday life: none may be drawn with regard to more strenuous activities such as sport or in trauma.

Purpose: To assess if ACL reconstruction restores normal knee kinematics.

Methods: Tibiofemoral motion was assessed weight-bearing through the arc of flexion from 0 to 90° in ten patients who were at least 6 months following successful hamstring graft ACL reconstruction. Lachman’s test was also performed using dynamic MRI. Mid-medial and mid-lateral images were analysed in all positions to assess the tibiofemoral relationship.

Results: The laxity of the reconstructed knees was reduced to within normal limits. However the normal tibiofemoral relationship was not restored after ACL reconstruction with persistent anterior subluxation of the lateral tibial plateau throughout the arc of flexion 0–90°(p< 0.001).

Conclusion: Successful ACL reconstruction reduces joint laxity and improves stability but it does not restore normal knee kinematics.

Introduction Techniques of joint motion study have been limited in value by being cadaveric, or if living, non-weight-bearing, or involving two-dimensional imaging [fluoroscopy]. MRI is attractive in providing no exposure to ionising radiation, and having the potential for analysis in three dimensions. Vertical-access open MRI, designed to allow invasive procedures within the imaging volume of the magnet, can be used to allow assessment of the knee in the standing living subject. A ‘tracking device’ can maintain the same plane of scan despite incremental movements of the joint. This allows imaging of a single slice of the joint throughout the range of knee motion.

Methods A series of studies have been undertaken employing this technique to establish tibio-femoral kinematics in the normal, ACL deficient, and post ACL reconstruction knee. In addition the kinematics of the Lachman’s test have been studied.

Results The sagittal plane results for the mid-medial and mid-lateral compartments of the normal knee show very different patterns of motion of the femur on the tibia during flexion. There is little antero-posterior position change medially but the lateral femur moves a considerable way back on the tibia. This differential motion equates to femoral external rotation [tibial internal rotation] as the knee flexes. The same pattern of movement occurs and to the same magnitude, but with the tibia in a more anterior position throughout. The ACL reconstructed group had very good clinical outcome, and their laxity was reduced. However the pattern of the tibio-femoral motion was same as the ACL deficient knees.

Conclusions Our results question the widely held concepts of femoral ‘roll-back’, mediated by tension in the cruciate ligaments. The implications are potentially very far-reaching for knee arthroplasty technique and design and knee ligament injury and treatment. It may also be possible to explain, as a consequence of normal tibio-femoral motion, a theory of causation of the usual pattern of osteoarthritis affecting the antero-medial part of the tibia.

In relation to the conduct of this study, one or more of the authors is in receipt of a research grant from a non-commercial source.

Mosaicplasty¹ and Autologous Chondrocyte Implantation² (ACI) are both modern cartilage repair techniques used to repair symptomatic articular cartilage defects in the knee, based on small osteochondral grafts and cultured chondrocytes respectively. The aim is the restoration of articular cartilage, but until now there is no data comparing the two methods.

100 consecutive patients aged 15–45 with a symptomatic articular cartilage lesion in the knee suitable for cartilage repair were randomised at arthroscopic assessment to undergo either mosaicplasty or ACI. 42 patients underwent mosaicplasty, 58 had ACI. Mean age at time of surgery was 31 years and the average defect size 4. 66 cm².

46% of the defects were post-traumatic, 19% had osteochondritis dissecans, 14% had chondromalacia patella and 16% had lesions of unknown aetiology. 53% had a medial femoral condyle lesion, 25% patella, 18% lateral femoral condyle, 3% trochlea and there was one defect of the lateral tibial plateau.

The mean duration of symptoms was 7. 2 years and the average number of previous operations (excluding arthroscopies) was 1. 5. Only 6 patients had no prior surgical interventions to the affected knee. The mean follow-up was 1. 7 years.

Patients were evaluated using Modified Cincinnati and Stanmore Functional rating systems, visual analogue scores and clinical assessment. Arthroscopy and biopsy was performed at one year and repair assessed with the International Cartilage Repair Society grading system.

Clinical results at one year showed 70% of mosaic-plasty patients and 87% of ACI patients had a good or excellent result. Arthroscopy at one year demonstrated more complete healing in ACI patients. Eleven (26%) of the mosaicplasty group subsequently failed clinically and arthroscopically, with peak failure at 2 years.

At one year follow-up, both techniques of articular cartilage repair can be useful in selected patients. ACI is preferred for lesions of the patella. Long-term follow-up is needed to assess the durability of articular cartilage repair using these methods, in particular mosaicplasty which showed signs of progressive failure over 2 years.

Autologous Chondrocyte Implantation’ (ACI) is a cartilage repair technique that involves implantation of cultured chondrocytes beneath a membrane of autologous periosteum. In this study a porcine biodegradable membrane was also used to assess its effectiveness. The aim is to restore articular cartilage to symptomatic defects, rather than initiating a fibrocartilagenous repair.

We undertook a prospective study of 125 consecutive patients who underwent ACI. Average age at the time of surgery was 30. 9 years (range 14 – 49), 55% of patients were male. The average size of the defect was 4. 35 cm².

44% of defects were attributable to known traumatic incidents, 2 1 % had osteochondritis dessicans, 18% chondromalacia patella, 12% had defects of unknown aetiology and 5% other.

The average duration of symptoms prior to this surgery was 7. 16 years. The mean number of previous operations (excluding arthroscopies) was 1. 6. Only 9 patients had no previous major surgery to the affected knee. 44% had defects of the medial femoral condyle, 31% patella, 20% lateral femoral condyle and 5% had a trochlea lesion. 26% of the defects were covered with periosteum and 74% with a porcine collagen membrane (chondrogide)

Minimum follow-up was six months, 70 patients had minimum follow-up of one year. Mean follow-up 18 months.

Patients were assessed using Modified Cincinnati and Stanmore Functional rating systems, visual analogue scores and clinical evaluation.

Arthroscopy and biopsy was performed at one year and the repair assessed using the International Cartilage Research Society grading system.

At one year follow-up overall 41 % patients had an excellent result, 48% good, 8% fair and 3% poor. For defects of the medial femoral condyle, 88% had a good or excellent result, 85% for the lateral femoral condyle and 80% for the patella.

61 patients were arthroscopically assessed at one year. 50/61 (82%) demonstrated ICRS grade 1 or 2 repair. Healing of the defect occurred with either a periosteum or chondrogide defect cover.

Results at one year suggest that ACI is a successful articular cartilage repair technique in selected patients. Long-term follow-up is required to assess the durability of the repair.

In 13 unloaded living knees we confirmed the findings previously obtained in the unloaded cadaver knee during flexion and external rotation/internal rotation using MRI. In seven loaded living knees with the subjects squatting, the relative tibiofemoral movements were similar to those in the unloaded knee except that the medial femoral condyle tended to move about 4 mm forwards with flexion. Four of the seven loaded knees were studied during flexion in external and internal rotation. As predicted, flexion (squatting) with the tibia in external rotation suppressed the internal rotation of the tibia which had been observed during unloaded flexion.

We present the first study in vivo of meniscal movement in normal knees under load. Using an open MR scanner, allowing imaging in physiological positions in near to real-time, 16 young footballers were scanned moving from full extension to 90° flexion in the sagittal and coronal planes. Excursion of the meniscal horns, radial displacement and meniscal height were measured.

On weight-bearing, the anterior horn of the medial meniscus moves through a mean of 7.1 mm and the posterior horn through 3.9 mm, with 3.6 mm of mediolateral radial displacement. The height of the anterior horn increases by 2.6 mm and that of the posterior horn by 2.0 mm. The anterior horn of the lateral meniscus moves 9.5 mm and the posterior horn 5.6 mm, with 3.7 mm of radial displacement. The height of the anterior horn increases by 4.0 mm, and that of the posterior horn by 2.4 mm. In non-weight-bearing, the anterior horn of the medial meniscus moves 5.4 mm and the posterior horn 3.8 mm, with 3.3 mm of radial displacement. The anterior horn of the lateral meniscus moves 6.3 mm, and the posterior horn 4.0 mm, with 3.4 mm of radial displacement. The most significant differences between weight-bearing and non-weight-bearing were the movement and vertical height of the anterior horn of the lateral meniscus.

The pathogenesis of slipped upper femoral epiphysis is unknown but the condition has been linked with various endocrine disorders. Nine patients with slipped epiphyses in association with primary juvenile hypothyroidism are presented. In all patients, slipping occurred or symptoms developed in the affected hip before the hypothyroidism was diagnosed. A generalised pathology was suggested by the absence of trauma (8 patients), by bilateral slipping (6 patients), and by obesity and short stature in all patients. All cases had delayed skeletal maturation and characteristic metaphysial changes were seen on their radiographs. The clinical diagnosis of juvenile hypothyroidism can be difficult but it merits consideration in patients who have a slipped upper femoral epiphysis in association with short stature, obesity, delay in skeletal maturity, or any one of these.

Adults with deformities of the lower limb due to spasticity may be considerably improved by operation, but thorough pre-operative assessment as an inpatient is essential in order to pinpoint the disability. The commonest deformity is equinovarus which often responds to simple operative procedures. The results of seventy-seven operative procedures in fifty patients are recorded. Correction once achieved is stable and the deformity does not recur.