Aims

There are limited long-term studies reporting on outcomes of the Zimmer Modular Revision (ZMR) stem, and concerns remain regarding failure. Our primary aim was to determine long-term survival free from all-cause revision and stem-related failure for this modular revision stem in revision total hip arthroplasty (THA). Secondary aims included evaluating radiological and functional outcomes.

Aims

Several different designs of hemiarthroplasty are used to treat intracapsular fractures of the proximal femur, with large variations in costs. No clinical benefit of modular over monoblock designs has been reported in the literature. Long-term data are lacking. The aim of this study was to report the ten-year implant survival of commonly used designs of hemiarthroplasty.

Aims

The aim of this study was to describe services available to patients with periprosthetic femoral fracture (PPFF) in England and Wales, with focus on variation between centres and areas for care improvement.

Aims

Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings.

Aims

Within healthcare, several measures are used to quantify and compare the severity of health conditions. Two common measures are disability weight (DW), a context-independent value representing severity of a health state, and utility weight (UW), a context-dependent measure of health-related quality of life. Neither of these measures have previously been determined for developmental dysplasia of the hip (DDH). The aim of this study is to determine the DW and country-specific UWs for DDH.

Aims

Several short- and mid-term studies have shown minimal liner wear of highly cross-linked polyethylene (HXLPE) in total hip arthroplasty (THA), but the safety of using thinner HXLPE liners to maximize femoral head size remains uncertain. The objective of this study was to analyze clinical survival and radiological wear rates of patients with HXLPE liners, a 36 mm femoral head, and a small acetabular component with a minimum of ten years’ follow-up.

Aims

Hip fracture commonly affects the frailest patients, of whom many are care-dependent, with a disproportionate risk of contracting COVID-19. We examined the impact of COVID-19 infection on hip fracture mortality in England.

Aims

Despite multiple trials and case series on hip hemiarthroplasty designs, guidance is still lacking on which implant to use. One particularly deficient area is long-term outcomes. We present over 1,000 consecutive cemented Thompson’s hemiarthroplasties over a ten-year period, recording all accessible patient and implant outcomes.

Aims

Orthopaedic surgeries are complex, frequently performed procedures associated with significant haemorrhage and perioperative blood transfusion. Given refinements in surgical techniques and changes to transfusion practices, we aim to describe contemporary transfusion practices in orthopaedic surgery in order to inform perioperative planning and blood banking requirements.

Aims

Highly cross-linked polyethylene (HXLPE) has greatly improved the durability of total hip arthroplasty (THA) in young patients because of its improved wear characteristics. Few studies have followed this population into the second decade, and therefore the purpose of this investigation was to evaluate the clinical outcome for THA patients 50 years of age and younger at a minimum of 15 years postoperatively. The second purpose was to evaluate the radiological findings secondary to wear or mechanical failure of the implant.

Aims

The purpose of our study was to determine which groups of orthopaedic providers favour virtual care, and analyze overall orthopaedic provider perceptions of virtual care. We hypothesize that providers with less clinical experience will favour virtual care, and that orthopaedic providers overall will show increased preference for virtual care during the COVID-19 pandemic and decreased preference during non-pandemic circumstances.

Aims

Malreduction of the syndesmosis has been reported in up to 52% of patients after fixation of ankle fractures. Multiple radiological parameters are used to define malreduction; there has been limited investigation of the accuracy of these measurements in differentiating malreduction from inherent anatomical asymmetry. The purpose of this study was to identify the prevalence of positive malreduction standards within the syndesmosis of native, uninjured ankles.

Aims

Extracellular matrix (ECM) and its architecture have a vital role in articular cartilage (AC) structure and function. We hypothesized that a multi-layered chitosan-gelatin (CG) scaffold that resembles ECM, as well as native collagen architecture of AC, will achieve superior chondrogenesis and AC regeneration. We also compared its in vitro and in vivo outcomes with randomly aligned CG scaffold.

Aims

Our rural orthopaedic service has undergone service restructure during the COVID-19 pandemic in order to sustain hip fracture care. All adult trauma care has been centralised to the Royal Shrewsbury Hospital for assessment and medical input, before transferring those requiring operative intervention to the Robert Jones and Agnes Hunt Orthopaedic Hospital. We aim to review the impact of COVID-19 on hip fracture workload and service changes upon management of hip fractures.

Aims

Dual mobility (DM) bearings are an attractive treatment option to obtain hip stability during challenging primary and revision total hip arthroplasty (THA) cases. The purpose of this study was to analyze data submitted to the American Joint Replacement Registry (AJRR) to characterize utilization trends of DM bearings in the USA.

Aims

Our objective is to describe our early and mid-term results with the use of a new simple primary knee prosthesis as an articulating spacer in planned two-stage management for infected knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a complete two-stage revision.

Aims

The practice of overlapping surgery has been increasing in the delivery of orthopaedic surgery, aiming to provide efficient, high-quality care. However, there are concerns about the safety of this practice. The purpose of this study was to examine the safety and efficacy of a model of partially overlapping surgery that we termed ‘swing room’ in the practice of primary total hip (THA) and knee arthroplasty (TKA).

Aims

Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity.

Aims

We investigated the long-term performance of the Tripolar Trident acetabular component used for recurrent dislocation in revision total hip arthroplasty. We assessed: 1) rate of re-dislocation; 2) incidence of complications requiring re-operation; and 3) Western Ontario and McMaster Universities osteoarthritis index (WOMAC) pain and functional scores.

Aims

Custom flange acetabular components (CFACs) are a patient-specific option for addressing large acetabular defects at revision total hip arthroplasty (THA), but patient and implant characteristics that affect survivorship remain unknown. This study aimed to identify patient and design factors related to survivorship.

Aims

Fretting and corrosion at the modular head/neck junction, known as trunnionosis, in total hip arthroplasty (THA) is a cause of adverse reaction to metal debris (ARMD). We describe the outcome of revision of metal-on-polyethylene (MoP) THA for ARMD due to trunnionosis with emphasis on the risk of major complications.

Aims

Recently, there has been considerable interest in quantifying the associations between bony abnormalities around and in the hip joint and osteoarthritis (OA). Our aim was to investigate the relationships between acetabular undercoverage, acetabular overcoverage, and femoroacetabular impingement (FAI) with OA of the hip, which currently remain controversial.

Aims

The best time for definitive orthopaedic care is often unclear in patients with multiple injuries. The objective of this study was make a prospective assessment of the safety of our early appropriate care (EAC) strategy and to evaluate the potential benefit of additional laboratory data to determine readiness for surgery.

Fractures around total knee arthroplasties pose a significant surgical challenge. Most can be managed with osteosynthesis and salvage of the replacement. The techniques of fixation of these fractures and revision surgery have evolved and so has the assessment of outcome. This specialty update summarises the current evidence for the classification, methods of fixation, revision surgery and outcomes of the management of periprosthetic fractures associated with total knee arthroplasty.

Cite this article: Bone Joint J 2016;98-B:1489–96.

This article presents a unified clinical theory that links established facts about the physiology of bone and homeostasis, with those involved in the healing of fractures and the development of nonunion. The key to this theory is the concept that the tissue that forms in and around a fracture should be considered a specific functional entity. This ‘bone-healing unit’ produces a physiological response to its biological and mechanical environment, which leads to the normal healing of bone. This tissue responds to mechanical forces and functions according to Wolff’s law, Perren’s strain theory and Frost’s concept of the “mechanostat”. In response to the local mechanical environment, the bone-healing unit normally changes with time, producing different tissues that can tolerate various levels of strain. The normal result is the formation of bone that bridges the fracture – healing by callus. Nonunion occurs when the bone-healing unit fails either due to mechanical or biological problems or a combination of both. In clinical practice, the majority of nonunions are due to mechanical problems with instability, resulting in too much strain at the fracture site. In most nonunions, there is an intact bone-healing unit. We suggest that this maintains its biological potential to heal, but fails to function due to the mechanical conditions. The theory predicts the healing pattern of multifragmentary fractures and the observed morphological characteristics of different nonunions. It suggests that the majority of nonunions will heal if the correct mechanical environment is produced by surgery, without the need for biological adjuncts such as autologous bone graft.

Cite this article: Bone Joint J 2016;98-B:884–91.

Aims

Reconstruction of the acetabulum after failed total hip arthroplasty (THA) can be a surgical challenge in the presence of severe bone loss. We report the long-term survival of a porous tantalum revision acetabular component, its radiological appearance and quality of life outcomes.

Aims

The purpose of this study was to report the experience of dynamic intraligamentary stabilisation (DIS) using the Ligamys device for the treatment of acute ruptures of the anterior cruciate ligament (ACL).

Aims

Glenoid bone loss can be a challenging problem when revising a shoulder arthroplasty. Precise pre-operative planning based on plain radiographs or CT scans is essential. We have investigated a new radiological classification system to describe the degree of medialisation of the bony glenoid and that will indicate the amount of bone potentially available for supporting a glenoid component. It depends on the relationship between the most medial part of the articular surface of the glenoid with the base of the coracoid process and the spinoglenoid notch: it classifies the degree of bone loss into three types.

It also attempts to predict the type of glenoid reconstruction that may be possible (impaction bone grafting, structural grafting or simple non-augmented arthroplasty) and gives guidance about whether a pre-operative CT scan is indicated.

Aims

We present a case series of ten metal-on-polyethylene total hip arthroplasties (MoP THAs) with delayed dislocation associated with unrecognised adverse local tissue reaction due to corrosion at the trunnion and pseudotumour formation.

Objectives

Sagittal alignment of the lumbosacral spine, and specifically pelvic incidence (PI), has been implicated in the development of spine pathology, but generally ignored with regards to diseases of the hip. We aimed to determine if increased PI is correlated with higher rates of hip osteoarthritis (HOA). The effect of PI on the development of knee osteoarthritis (KOA) was used as a negative control.

Tapered fluted titanium stems are increasingly used for femoral revision arthroplasty. They are available in modular and non-modular forms. Modularity has advantages when the bone loss is severe, the proximal femur is mis shapen or the surgeon is unfamiliar with the implant, but it introduces the risk of fracture of the stem at the junction between it and the proximal body segment. For that reason, and while awaiting intermediate-term results of more recently introduced designs of this junction, non-modularity has attracted attention, at least for straightforward revision cases.

We review the risks and causes of fracture of tapered titanium modular revision stems and present an argument in favour of the more selective use of modular designs.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):50–3.

This study aimed to determine the long-term functional, clinical and radiological outcomes in patients with Schatzker IV to VI fractures of the tibial plateau treated with an Ilizarov frame. Clinical, functional and radiological assessment was carried out at a minimum of one year post-operatively. A cohort of 105 patients (62 men, 43 women) with a mean age of 49 years (15 to 87) and a mean follow-up of 7.8 years (1 to 19) were reviewed. There were 18 type IV, 10 type V and 77 type VI fractures. All fractures united with a mean time to union of 20.1 weeks (10.6 to 42.3). No patient developed a deep infection. The median range of movement (ROM) of the knee was 110^o and the median Iowa score was 85.

Our study demonstrates good long-term functional outcome with no deep infection; spanning the knee had no detrimental effect on the ROM or functional outcome.

High-energy fractures of the tibial plateau may be treated effectively with a fine wire Ilizarov fixator.

Cite this article: Bone Joint J 2015;97-B:1693–7.

Adverse reaction to wear and corrosion debris is a cause for concern in total hip arthroplasty (THA). Modular junctions are a potential source of such wear products and are associated with secondary pseudotumour formation.

We present a consecutive series of 17 patients treated at our unit for this complication following metal-on-highly cross-linked polyethylene (MoP) THA. We emphasise the risk of misdiagnosis as infection, and present the aggregate laboratory results and pathological findings in this series.

The clinical presentation was pain, swelling or instability. Solid, cystic and mixed soft-tissue lesions were noted on imaging and confirmed intra-operatively. Corrosion at the head–neck junction was noted in all cases. No bacteria were isolated on multiple pre- and intra-operative samples yet the mean erythrocyte sedimentation rate was 49 (9 to 100) and C-reactive protein 32 (0.6 to 106) and stromal polymorphonuclear cell counts were noted in nine cases.

Adverse soft–tissue reactions can occur in MoP THA owing to corrosion products released from the head–neck junction. The diagnosis should be carefully considered when investigating pain after THA. This may avoid the misdiagnosis of periprosthetic infection with an unidentified organism and mitigate the unnecessary management of these cases with complete single- or two-stage exchange.

Cite this article: Bone Joint J 2015;97-B:1024–1030.

Non-modular tapered fluted, titanium stems are available for use in femoral revision. The combination of taper and flutes on the stem provides axial and rotational stability, respectively. The material and surface properties of the stem promotes bone on-growth. If the surgeon is confident and reasonably experienced in the surgical use of this sort of design and the case is relatively straightforward, a non-modular design is effective. It also potentially reduces implant inventory, and circumvents the potential problems of taper junction corrosion and fatigue fracture. There are reports of excellent survival, good clinical and functional results and evidence of subsequent increase in proximal bone stock.

Cite this article: Bone Joint J 2014;96-B(11 Suppl A):56–9.

Objectives

The aim of this study was to examine whether asymmetric loading influences macrophage elastase (MMP12) expression in different parts of a rat tail intervertebral disc and growth plate and if MMP12 expression is correlated with the severity of the deformity.

The management of spinal deformity in children with univentricular cardiac pathology poses significant challenges to the surgical and anaesthetic teams. To date, only posterior instrumented fusion techniques have been used in these children and these are associated with a high rate of complications. We reviewed our experience of both growing rod instrumentation and posterior instrumented fusion in children with a univentricular circulation.

Six children underwent spinal corrective surgery, two with cavopulmonary shunts and four following completion of a Fontan procedure. Three underwent growing rod instrumentation, two had a posterior fusion and one had spinal growth arrest. There were no complications following surgery, and the children undergoing growing rod instrumentation were successfully lengthened. We noted a trend for greater blood loss and haemodynamic instability in those whose surgery was undertaken following completion of a Fontan procedure. At a median follow-up of 87.6 months (interquartile range (IQR) 62.9 to 96.5) the median correction of deformity was 24.2% (64.5° (IQR 46° to 80°) vs 50.5° (IQR 36° to 63°)).

We believe that early surgical intervention with growing rod instrumentation systems allows staged correction of the spinal deformity and reduces the haemodynamic insult to these physiologically compromised children. Due to the haemodynamic changes that occur with the completed Fontan circulation, the initial scoliosis surgery should ideally be undertaken when in the cavopulmonary shunt stage.

Cite this article: Bone Joint J 2014;96-B:94–9.

Tapered, fluted, modular, titanium stems are increasingly popular in the operative management of Vancouver B2 and selected B3 peri-prosthetic femoral fractures. We have reviewed the results at our institution looking at stem survival and clinical outcomes and compared this with reported outcomes in the literature. Stem survival at a mean of 54 months was 96% in our series and 97% for combined published cases. Review of radiology showed maintenance or improvement of bone stock in 89% of cases with high rates of femoral union. Favourable clinical outcome scores have reported by several authors. No difference in survival or clinical scores was observed between B2 and B3 fractures. Tapered stems are a useful option in revision for femoral fracture across the spectrum of femoral bone deficiency.

Cite this article: Bone Joint J 2013;95-B, Supple A:17–20.

The aim of this prospective randomised study was to compare the clinical and radiological results of a cemented all-polyethylene Ultima acetabular component with those of a cementless porous-coated acetabular component (PFC) following total hip replacement (THR). A total of 287 patients received either a polyethylene acetabular component (group A) or a cobalt–chromium porous-coated component (group B) with an identical cemented femoral component and 28 mm cobalt-chromium head, thus making it the largest study of its type. Patients were evaluated radiologically and clinically using the Harris hip score (HHS). Group A comprised 183 patients (73 male, 110 female) with a mean age of 71.3 years (55 to 89). Group B comprised 104 patients (48 male, 56 female) with a mean age of 69.8 years (56 to 89). A total of 16 patients (13 in Group A, three in Group B) did not have post-operative data for analysis. The mean follow-up in group A was 7.52 years (0.4 to 15.0) and in Group B 7.87 years (0.5 to 14.0).

At final follow-up the mean HHS was similar between groups A and B (74.5 (25 to 100) and 78.0 (37 to 100), respectively; p = 0.068). The total number of revisions for any cause was 28, 17 of which were in group A and 11 in group B. The ten-year survivorship was 86.8% (95% confidence interval (CI) 78.4 to 92.1) and 89.2% (95% CI 78.3 to 94.8) for groups A and B, respectively (log-rank p-value = 0.938). A total of 20 cemented and two cementless acetabular components had evidence of acetabular radiolucencies or acetabular component migration at last follow-up (p = 0.001).

These results indicate that patients with a cemented all-polyethylene and cementless porous-coated polyethylene lined acetabular component have similar long-term clinical outcomes.

Tapered, fluted, modular, titanium stems have a long history in Europe and are increasing in popularity in North America. We have reviewed the results at our institution looking at stem survival and clinical outcomes. Radiological outcomes and quality of life assessments have been performed and compared to cylindrical non-modular cobalt chromium stems. Survival at five years was 94%. This fell to 85% at ten years due to stem breakage with older designs. Review of radiology showed maintenance or improvement of bone stock in 87% of cases. Outcome scores were superior in tapered stems despite worse pre-operative femoral deficiency. Tapered stems have proved to be a useful alternative in revision total hip arthroplasty across the spectrum of femoral bone deficiency.

Antibiotic impregnated articulating spacers are used in two-stage revision total knee arthroplasty to deliver local antibiotic therapy while preserving function. We have observed infection control in greater than 95% of cases with functional outcomes approaching those seen in revision for aseptic loosening. Higher failure has been observed with methicillin resistant organisms.

There is little information about the management of peri-prosthetic fracture of the humerus after total shoulder replacement (TSR). This is a retrospective review of 22 patients who underwent a revision of their original shoulder replacement for peri-prosthetic fracture of the humerus with bone loss and/or loose components. There were 20 women and two men with a mean age of 75 years (61 to 90) and a mean follow-up 42 months (12 to 91): 16 of these had undergone a previous revision TSR. Of the 22 patients, 12 were treated with a long-stemmed humeral component that bypassed the fracture. All their fractures united after a mean of 27 weeks (13 to 94). Eight patients underwent resection of the proximal humerus with endoprosthetic replacement to the level of the fracture. Two patients were managed with a clam-shell prosthesis that retained the original components. The mean Oxford shoulder score (OSS) of the original TSRs before peri-prosthetic fracture was 33 (14 to 48). The mean OSS after revision for fracture was 25 (9 to 31). Kaplan-Meier survival using re-intervention for any reason as the endpoint was 91% (95% confidence interval (CI) 68 to 98) and 60% (95% CI 30 to 80) at one and five years, respectively.

There were two revisions for dislocation of the humeral head, one open reduction for modular humeral component dissociation, one internal fixation for nonunion, one trimming of a prominent screw and one re-cementation for aseptic loosening complicated by infection, ultimately requiring excision arthroplasty. Two patients sustained nerve palsies.

Revision TSR after a peri-prosthetic humeral fracture associated with bone loss and/or loose components is a salvage procedure that can provide a stable platform for elbow and hand function. Good rates of union can be achieved using a stem that bypasses the fracture. There is a high rate of complications and function is not as good as with the original replacement.

Scapulothoracic fusion (STF) for painful winging of the scapula in neuromuscular disorders can provide effective pain relief and functional improvement, but there is little information comparing outcomes between patients with dystrophic and non-dystrophic conditions. We performed a retrospective review of 42 STFs in 34 patients with dystrophic and non-dystrophic conditions using a multifilament trans-scapular, subcostal cable technique supported by a dorsal one-third semi-tubular plate. There were 16 males and 18 females with a mean age of 30 years (15 to 75) and a mean follow-up of 5.0 years (2.0 to 10.6). The mean Oxford shoulder score improved from 20 (4 to 39) to 31 (4 to 48). Patients with non-dystrophic conditions had lower overall functional scores but achieved greater improvements following STF. The mean active forward elevation increased from 59° (20° to 90°) to 97° (30° to 150°), and abduction from 51° (10° to 90°) to 83° (30° to 130°) with a greater range of movement achieved in the dystrophic group. Revision fusion for nonunion was undertaken in five patients at a mean time of 17 months (7 to 31) and two required revision for fracture. There were three pneumothoraces, two rib fractures, three pleural effusions and six nonunions. The main risk factors for nonunion were smoking, age and previous shoulder girdle surgery.

STF is a salvage procedure that can provide good patient satisfaction in 82% of patients with both dystrophic and non-dystrophic pathologies, but there was a relatively high failure rate (26%) when poor outcomes were analysed. Overall function was better in patients with dystrophic conditions which correlated with better range of movement; however, patients with non-dystrophic conditions achieved greater functional improvement.

This review summarises the opinions and conclusions reached from a symposium on infected total knee replacement (TKR) held at the British Association of Surgery of the Knee (BASK) annual meeting in 2011. The National Joint Registry for England and Wales reported 5082 revision TKRs in 2010, of which 1157 (23%) were caused by infection. The diagnosis of infection beyond the acute post-operative stage relies on the identification of the causative organism by aspiration and analysis of material obtained at arthroscopy. Ideal treatment then involves a two-stage surgical procedure with extensive debridement and washout, followed by antibiotics. An articulating or non-articulating drug-eluting cement spacer is used prior to implantation of the revision prosthesis, guided by the serum level of inflammatory markers. The use of a single-stage revision is gaining popularity and we would advocate its use in certain patients where the causative organism is known, no sinuses are present, the patient is not immunocompromised, and there is no radiological evidence of component loosening or osteitis.

It is our opinion that single-stage revision produces high-quality reproducible results and will soon achieve the same widespread acceptance as it does in infected hip arthroplasty.

We report the outcome at ten to 15 years of two-stage revision for hip infection in 99 patients using the Prostalac articulated hip spacer system.

All the patients were contacted to determine their current functional and infection status using the Oxford-12, Short form-12, and Western Ontario and McMaster University Osteoarthritis Index questionnaires. A total of 11 of the 99 patients had a further infection, of whom seven responded to repeat surgery with no further sequelae. The mean interval between the stages was five months (1 to 36). We were able to review 48 living patients, with a mean age of 72 years (46 to 86), 34 (71%) of whom provided health-related quality-of-life outcome scores.

The mean follow-up was 12 years (10 to 15). The long-term success rate was 89% and with additional surgery this rose to 96%. The mean global Western Ontario and McMaster University Osteoarthritis Index score was 80.6 (sd 18.3). The mean Oxford-12 score was 74.0 (sd 22.3), and the mean Short form-12 score was 53.1 (sd 9.4) (mental) and 33.5 (sd 13.5) (physical). The mean satisfaction score was 90.5 (sd 15.3).

Two-stage revision for hip infection using a Prostalac interim spacer offers a predictable and lasting solution for patients with this difficult problem.

Fractures of the odontoid in children with an open basilar synchondrosis differ from those which occur in older children and adults. We have reviewed the morphology of these fractures and present a classification system for them.

There were four distinct patterns of fracture (types IA to IC and type II) which were distinguished by the site of the fracture, the degree of displacement and the presence or absence of atlantoaxial dislocation. Children with a closed synchondrosis were classified using the system devised by Anderson and D’Alonzo. Those with an open synchondrosis had a comparatively lower incidence of traumatic brain injury, a higher rate of missed diagnosis and a shorter mean stay in hospital. Certain subtypes (type IA and type II) are likely to be missed on plain radiographs and therefore more advanced imaging is recommended. We suggest staged treatment with initial stabilisation in a Halo body jacket and early fusion for those with unstable injuries, severe displacement or neurological involvement.

This study compared the effect of a computer-assisted and a traditional surgical technique on the kinematics of the glenohumeral joint during passive abduction after hemiarthroplasty of the shoulder for the treatment of fractures. We used seven pairs of fresh-frozen cadaver shoulders to create simulated four-part fractures of the proximal humerus, which were then reconstructed with hemiarthroplasty and reattachment of the tuberosities. The specimens were randomised, so that one from each pair was repaired using the computer-assisted technique, whereas a traditional hemiarthroplasty without navigation was performed in the contralateral shoulder. Kinematic data were obtained using an electromagnetic tracking device.

The traditional technique resulted in posterior and inferior translation of the humeral head. No statistical differences were observed before or after computer-assisted surgery.

Although it requires further improvement, the computer-assisted approach appears to allow glenohumeral kinematics to more closely replicate those of the native joint, potentially improving the function of the shoulder and extending the longevity of the prosthesis.

We compared the outcome of patients treated for an intertrochanteric fracture of the femoral neck with a locked, long intramedullary nail with those treated with a dynamic hip screw (DHS) in a prospective randomised study.

Each patient who presented with an extra-capsular hip fracture was randomised to operative stabilisation with either a long intramedullary Holland nail or a DHS. We treated 92 patients with a Holland nail and 98 with a DHS. Pre-operative variables included the Mini Mental test score, patient mobility, fracture pattern and American Society of Anesthesiologists grading. Peri-operative variables were anaesthetic time, operating time, radiation time and blood loss. Post-operative variables were time to mobilising with a frame, wound infection, time to discharge, time to fracture union, and mortality.

We found no significant difference in the pre-operative variables. The mean anaesthetic and operation times were shorter in the DHS group than in the Holland nail group (29.7 vs 40.4 minutes, p < 0.001; and 40.3 vs 54 minutes, p < 0.001, respectively). There was an increased mean blood loss within the DHS group versus the Holland nail group (160 ml vs 78 ml, respectively, p < 0.001). The mean time to mobilisation with a frame was shorter in the Holland nail group (DHS 4.3 days, Holland nail 3.6 days, p = 0.012). More patients needed a post-operative blood transfusion in the DHS group (23 vs seven, p = 0.003) and the mean radiation time was shorter in this group (DHS 0.9 minutes vs Holland nail 1.56 minutes, p < 0.001). The screw of the DHS cut out in two patients, one of whom underwent revision to a Holland nail. There were no revisions in the Holland nail group. All fractures in both groups were united when followed up after one year.

We conclude that the DHS can be implanted more quickly and with less exposure to radiation than the Holland nail. However, the resultant blood loss and need for transfusion is greater. The Holland nail allows patients to mobilise faster and to a greater extent. We have therefore adopted the Holland nail as our preferred method of treating intertrochanteric fractures of the hip.

Contracture of the collateral ligaments is considered to be an important factor in post-traumatic stiffness of the elbow. We reviewed the results of isolated release of the medial collateral ligament in a series of 14 patients with post-traumatic loss of elbow flexion treated between 1998 and 2002. There were nine women and five men with a mean age of 45 years (17 to 76). They were reviewed at a mean follow-up of 25 months (9 to 48). The operation was performed through a longitudinal posteromedial incision centred over the ulnar nerve. After decompression of the ulnar nerve, release of the medial collateral ligament was done sequentially starting with the posterior bundle and the transverse component of the ligament, with measurement of the arc of movement after each step. If full flexion was not achieved the posterior half of the anterior bundle of the medial collateral ligament was released.

At the latest follow-up, the mean flexion of the elbow improved significantly from 96° (85° to 115°) pre-operatively to 130° (110° to 150°) at final follow-up (p = 0.001). The mean extension improved significantly from 43° (5° to 90°) pre-operatively to 22° (5° to 40°) at final follow-up (p = 0.003). There was a significant improvement in the functional outcome. The mean Broberg and Morrey score increased from a mean of 54 points (29.5 to 85) pre-operatively to 87 points (57 to 99) at final follow-up (p < 0.001). All the patients had normal elbow stability.

Our results indicate that partial surgical release of the medial collateral ligament is associated with improved range of movement of the elbow in patients with post-traumatic stiffness, but was less effective in controlling pain.

A prospective cohort of 222 patients who underwent revision hip replacement between April 2001 and March 2004 was evaluated to determine predictors of function, pain and activity level between one and two years post-operatively, and to define quality of life outcomes using validated patient reported outcome tools. Predictive models were developed and proportional odds regression analyses were performed to identify factors that predict quality of life outcomes at one and two years post-operatively. The dependent outcome variables were the Western Ontario and McMaster Osteoarthritis Index (WOMAC) function and pain scores, and University of California Los Angeles activity scores. The independent variables included patient demographics, operative factors, and objective quality of life parameters, including pre-operative WOMAC, and the Short Form-12 mental component score.

There was a significant improvement (t-test, p < 0.001) in all patient quality of life scores. In the predictive model, factors predictive of improved function (original regression analyses, p < 0.05) included a higher pre-operative WOMAC function score (p < 0.001), age between 60 and 70 years (p < 0.037), male gender (p = 0.017), lower Charnley class (p < 0.001) and aseptic loosening being the indication for revision (p < 0.003). Using the WOMAC pain score as an outcome variable, factors predictive of improvement included the pre-operative WOMAC function score (p = 0.001), age between 60 and 70 years (p = 0.004), male gender (p = 0.005), lower Charnley class (p = 0.001) and no previous revision procedure (p = 0.023). The pre-operative WOMAC function score (p = 0.001), the indication for the operation (p = 0.007), and the operating surgeon (p = 0.008) were significant predictors of the activity assessment at follow-up.

Predictors of quality of life outcomes after revision hip replacement were established. Although some patient-specific and surgery-specific variables were important, age, gender, Charnley class and pre-operative WOMAC function score had the most robust associations with outcome.

We report 79 cases of bone and joint tuberculosis between 1988 and 2005, eight of which were in the Caucasian population and 71 in the non-white population.

The diagnosis was made in the majority (73.4%) by positive bacteriology and/or histology. The mean age at the time of diagnosis was higher in the Caucasian group at 51.5 years (28 to 66) than in the South Asian group at 36.85 years (12 to 93). Only one patient had previous BCG immunisation.

The spine was the site most commonly affected (44.3%). Surgical stabilisation and/or decompression was performed in 23% of these cases because of cord compression on imaging or the presence of neurological signs.

A six-month course of chemotherapy comprising of an initial two months of rifampicin, isoniazide, pyrazinamide and sometimes ethambutol followed by four months treatment with rifampicin and isoniazide, was successful in all cases without proven drug resistance.

We describe the influence of the angle of immobilisation during partial weight-bearing on the forces across the extensor mechanism of the knee. Gait analysis was performed on eight healthy male subjects with the right knee in an orthotic brace locked at 0°, 10°, 20° and 30°, with the brace unlocked and also without a brace. The ground reaction force, the angle of the knee and the net external flexion movement about the knee were measured and the extensor mechanism force was calculated.

The results showed a direct non-linear relationship between the angle of knee flexion and the extensor mechanism force. When a brace was applied, the lowest forces occurred when the brace was locked at 0°. At 30° the forces approached the failure strength of some fixation devices. We recommend that for potentially unstable injuries of the extensor mechanism, when mobilising with partial weight-bearing, the knee should be flexed at no more than 10°.

In a 41-year-old man, right-sided infraspinatus muscle weakness was associated with compression of the suprascapular nerve caused by a spinoglenoid ganglion cyst. The lesion was confirmed using electromyography and MRI. In addition, arthroscopy showed an incomplete discoid labrum. The free inner edge of the labrum was removed as in a meniscectomy of a discoid meniscus in the knee joint. Arthroscopic decompression of the cyst was performed through a juxtaglenoid capsulotomy which was left open. Neurological function recovered completely.

Surgical access to the head of the radius is usually performed through a lateral approach. We present an alternative technique through a modified posterior approach which was developed following dissections of 22 human cadavers. An osteotomy of the supinator tuberosity was performed and reflected as a single unit with the attached annular ligament. Excellent exposure of the head of the radius was achieved, replacement of the head was undertaken and the osteotomy site repaired. The elbows were stable and had a full range of movement. The approach was then carried out on 13 patients for elective replacement of the head and was found to be safe and reproducible. In the patient group all osteotomies united, the elbows were stable and had an improved range of supination and pronation. There was no change in flexion and extension of the elbow. Complications included a haematoma and a reflex sympathetic dystrophy.

The modified posterior approach provides excellent access to the head and neck of the radius, gives good stability of the elbow and allows early mobilisation of the joint.

Fragility fractures of the ankle occur mainly in elderly osteoporotic women. They are inherently unstable and difficult to manage. There is a high incidence of complications with both non-operative and operative treatment.

We treated 12 such fractures by closed reduction and stabilisation using a retrograde calcaneotalotibial expandable nail. The mean age of patients was 84 years (75 to 95). All were women and were able to walk fully weight-bearing after surgery. There were no wound complications. One patient died from a myocardial infarction 24 days after surgery. The 11 other patients were followed up for a mean of 67 weeks (39 to 104).

All the fractures maintained satisfactory alignment and healed without delay. Six patients refused removal of the nail after union of the fracture. The functional rating using the scale of Olerud and Molander gave a mean score at follow-up of 61, compared with a pre-injury value of 70.

We studied 16 hips (eight cadaver specimens) using arthrography, arthroscopy and anatomical dissection, under incremental traction of up to a maximum of 64 kg, to determine the relationship of the portals to nearby neurovascular structures.

The distance of each arthroscopic portal (anterior, anterolateral, and posterolateral) to the associated neurovascular structures was measured after the application of 23 kg of traction.

Traction of up to 64 kg on the lower limb failed to produce evidence of labral or capsular injury. Furthermore, traction of 23 kg resulted in little change in the position of adjacent neurovascular structures relative to the standard arthroscopic portals.

Removal of well-fixed, cementless, acetabular components during revision arthroplasty remains a challenging problem. Further damage to host bone may limit options for reconstruction and compromise the long-term result of the revision operation. We report the results of 31 hips with well-fixed, cementless sockets which were removed using a new cup extraction system. In all hips the socket was removed without difficulty and with minimal further bone loss.

We have undertaken a prospective evaluation of health-related quality-of-life outcomes in 26 consecutive patients undergoing periacetabular osteotomy with a minimum follow-up of 24 months (24 to 42). The Western Ontario-Macmaster (WOMAC) and Short Form 36 (SF-36) outcome measures were evaluated preoperatively and at follow-up. Secondary outcome measures included retrospective assessment of sports activity and satisfaction with the procedure.

Follow-up data were available for 22 patients (85%). A significant improvement in the pain (p < 0.0001) and function (p < 0.0001) scales of the WOMAC and the SF-36 physical score (p < 0.0001) was seen. The mean sports activity score improved from 1.9 to 4.4, with a very high mean satisfaction rating of 89.7/100.

A significant improvement in both global and disease-specific health outcomes can be expected after this operation, with a high rate of satisfaction and improvement in sporting activities.

We have examined whether primary human muscle-derived cells can be used in ex vivo gene therapy to deliver BMP-2 and to produce bone in vivo. Two in vitro experiments and one in vivo experiment were used to determine the osteocompetence and BMP-2 secretion capacity of cells isolated from human skeletal muscle.

We isolated five different populations of primary muscle cells from human skeletal muscle in three patients. In the first in vitro experiment, production of alkaline phosphatase by the cells in response to stimulation by rhBMP-2 was measured and used as an indicator of cellular osteocompetence. In the second, secretion of BMP-2 was measured after the cell populations had been transduced by an adenovirus encoding for BMP-2. In the in vivo experiment, the cells were cotransduced with a retrovirus encoding for a nuclear localised β-galactosidase gene and an adenovirus encoding for BMP-2. The cotransduced cells were then injected into the hind limbs of severe combined immune-deficient (SCID) mice and analysed radiographically and histologically. The nuclear localised β-galactosidase gene allowed identification of the injected cells in histological specimens. In the first in vitro experiment, the five different cell populations all responded to in vitro stimulation of rhBMP-2 by producing higher levels of alkaline phosphatase when compared with non-stimulated cells. In the second, the five different cell populations were all successfully transduced by an adenovirus to express and secrete BMP-2. The cells secreted between 444 and 2551 ng of BMP-2 over three days. In the in vivo experiment, injection of the transduced cells into the hind-limb musculature of SCID mice resulted in the formation of ectopic bone at 1, 2, 3 and 4 weeks after injection. Retroviral labelling of the cell nuclei showed labelled human muscle-derived cells occupying locations of osteoblasts in the ectopic bone, further supporting their osteocompetence.

Cells from human skeletal muscle, because of their availability to orthopaedic surgeons, their osteocompetence, and their ability to express BMP-2 after genetic engineering, are an attractive cell population for use in BMP-2 gene therapy approaches.

We present a study of ten consecutive patients who underwent excision of thoracic or thoracolumbar hemivertebrae for either angular deformity in the coronal plane, or both coronal and sagittal deformity. Vertebral excision was carried out anteriorly alone in two patients. Seven patients had undergone previous posterior spinal fusion. Their mean age at surgery was 13.4 years (6 to 19). The mean follow-up was 78.5 months (20 to 180). The results were evaluated by radiological review of the preoperative, postoperative and most recent follow-up films.

The mean preoperative coronal curve was 78.2° (30 to 115) and was corrected to 33.9° (7 to 58) postoperatively, a mean correction of 59%. Preoperative coronal decompensation of 35 mm was improved to 11 mm postoperatively. Seven patients had significant coronal decompensation preoperatively, which was corrected to a physiological range postoperatively. There were no major complications and no neurological damage.

We have shown that resection of thoracic and thoracolumbar hemivertebrae can be performed safely, without undue risk of neurological compromise, in experienced hands.

The pathogenesis of aseptic loosening of total joint prostheses is not clearly understood. Two features are associated with loosened prostheses, namely, particulate debris and movement of the implant. While numerous studies have evaluated the cellular response to particulate biomaterials, few have investigated the influence of movement of the implant on the biological response to particles. Our aim was therefore to test the hypothesis that excessive mechanical stimulation of the periprosthetic tissues induces an inflammatory response and that the addition of particulate biomaterials intensifies this.

We allocated 66 adult Beagle dogs to four groups as follows: stable implants with (I) and without (II) particulate polymethylmethacrylate (PMMA) and moving implants with (III) and without (IV) particulate PMMA. They were then evaluated at 2, 4, 6, 12 and 24 weeks.

The stable implants were well tolerated and a thin, fibrous membrane of connective tissue was observed. There was evidence of positive staining in some cells for interleukin-6 (IL-6). Addition of particulate PMMA around the stable implants resulted in an increase in the fibroblastic response and positive staining for IL-6 and tumour necrosis factor-alpha (TNF-α). By contrast, movement of the implant resulted in an immediate inflammatory response characterised by large numbers of histiocytes and cytokine staining for IL-1ß, TNF-α and IL-6. Introduction of particulate PMMA aggravated this response. Animals with particulate PMMA and movement of the implant have an intense inflammatory response associated with accelerated bone loss.

Our results indicate that the initiation of the inflammatory response to biomaterial particles was much slower than that to gross mechanical instability. Furthermore, when there was both particulate debris and movement, there was an amplification of the adverse tissue response as evidenced by the presence of osteolysis and increases in the presence of inflammatory cells and their associated cytokines.

Caveolae, specialised regions of the cell membrane which have been detected in a wide range of mammalian cells, have not been described in bone cells. They are plasmalemmal invaginations, 50 to 100 nm in size, characterised by the presence of the structural protein, caveolin, which exists as three subtypes. Caveolin-1 and caveolin-2 are expressed in a wide range of cell types whereas caveolin-3 is thought to be a muscle-specific subtype. There is little information on the precise function of caveolae, but it has been proposed that they play an important role in signal transduction.

As the principal bone-producing cell, the osteoblast has been widely studied in an effort to understand the signalling pathways by which it responds to extracellular stimuli. Our aim in this study was to identify caveolae and their structural protein caveolin in normal human osteoblasts, and to determine which subtypes of caveolin were present. Confocal microscopy showed staining which was associated with the plasma membrane. Transmission electron microscopy revealed the presence of membrane invaginations of 50 to 100 nm, consistent with the appearance of caveolae. Finally, we isolated protein from these osteoblasts, and performed Western blotting using anti-caveolin primary antibodies. This revealed the presence of caveolin-1 and -2, while caveolin-3 was absent.

The identification of these structures and their associated protein may provide a significant contribution to our further understanding of signal transduction pathways in osteoblasts.

We studied the effect of the surface finish of the stem on the transfer of load in the proximal femur in a sheep model of cemented hip arthroplasty. Strain-gauge analysis and corresponding finite-element (FE) analysis were performed to assess the effect of friction and creep at the cement-stem interface.

No difference was seen between the matt and polished stems. FE analysis showed that the effects of cement creep and friction at the stem-cement interface on femoral strain were small compared with the effect of inserting a cemented stem.

There are few medium- and long-term data on the outcome of the use of proximal femoral structural allografts in revision hip arthroplasty. This is a study of a consecutive series of 40 proximal femoral allografts performed for failed total hip replacements using the same technique with a minimum follow-up of five years (mean 8.8 years; range 5 to 11.5 years). In all cases the stem was cemented into both the allograft and the host femur. The proximal femur of the host was resected in 37 cases.

There were four early revisions (10%), two for infection, one for nonunion of the allograft-host junction, and one for allograft resorption noted at the time of revision of a failed acetabular reconstruction. Junctional nonunion was seen in three patients (8%), two of whom were managed successfully by bone grafting, and bone grafting and plating respectively. Instability was observed in four (10%). Trochanteric nonunion was seen in 18 patients (46%) and trochanteric escape in ten of these (27%). The mean Harris hip score improved from 39 to 79. Severe resorption involving the full thickness of the allograft was seen in seven patients (17.5%). This progressed rapidly and silently, but has yet to cause failure of any of the reconstructions.

Profound resorption of the allograft may be related to a combination of factors, including a slow form of immune rejection, stress shielding and resorption due to mechanical disuse with solid cemented distal fixation, and the absence of any masking or protective effect which may be provided by the retention of the bivalved host bone as a vascularised onlay autograft. Although continued surveillance is warranted, the very good medium-term clinical results justify the continued use of structural allografts for failed total hip replacements with severe loss of proximal femoral bone.

We have previously described a simple and reproducible three-dimensional technique of CT for the measurement of the cover of the femoral head in acetabular dysplasia in adults. We now describe the application of this technique in ten patients with symptomatic dysplasia to assess the degree and direction of dysplasia and to measure the cover obtained at acetabular osteotomy.

The indices obtained gave a useful indication of the degree and direction of the dysplasia and confirmed which components had been used most efficiently to achieve cover. The information is easily presented in graphical form and gives a clearer indication of the cover obtained than the indices derived from plain radiographs.

We describe a patient with a Mason type-III fracture of the head of the radius associated with traumatic dislocation of the elbow. The radial head was intact throughout its circumference despite being completely detached from the shaft and devoid of any soft-tissue attachments. Severe comminution of the radial neck prevented reconstruction by internal fixation and precluded prosthetic replacement of the head. The head was fixed to the shaft with a tricortical iliac-crest bone graft which replaced the neck. Two years later, the patient had a stable elbow with flexion from 10° to 130°. Radiologically, the head of the radius appeared to be viable and the bone graft had incorporated.

Dental procedures may lead to a transient bacteraemia lasting for up to 30 minutes. Of the numerous cases of total hip arthroplasty (THA) reported which have been infected from haematogenous sources, dental procedures have been involved only infrequently. We reviewed the records of 2973 patients after THA. Of the late infections identified in 52 patients, three (6%) were strongly associated with a dental procedure. Infection was diagnosed by culture from the affected joint; Streptococcus viridans was identified in two cases and Peptostreptococcus in one. One patient had diabetes mellitus and another rheumatoid arthritis, both conditions predisposing to infection. The dental operations all lasted for more than 45 minutes and no patient received perioperative antibiotics.

Infection of a THA after dental procedures is more common than has been previously suspected. Patients with systemic disease, or who are undergoing extensive procedures, should be considered for prophylactic antibiotic treatment.

We examined macroscopically and microscopically 55 cadaver rotator-cuff tendons attached to their humeral heads to determine the distance between the edge of the articular cartilage and the tendon insertion of the supraspinatus (the width of the sulcus) and the score of regressive changes at the sulcus. In 33 specimens we measured the tensile strength. The width of the sulcus was correlated with the score of regressive changes and with the ultimate tensile strength of the supraspinatus tendon.

The width of the sulcus correlated positively with the score of regressive changes (r = 0.66, p < 0.0001), but there was a negative correlation between the latter and the ultimate tensile strength (r = −0.81, p = 0.001) and between the width of the sulcus and the ultimate tensile strength (r = −0.74, p = 0.004).

We believe that the width of the sulcus is a simple and useful clinical indicator of the integrity and the tensile strength of the supraspinatus tendon.

We have reviewed the results of 30 operations performed on 23 patients with Ficat stage-III or stage-IV osteonecrosis of the femoral head in which autogenous cortical and cancellous bone grafting had been performed through a so-called trapdoor made in the femoral head.

At a mean of 56 months (30 to 60) after operation 20 of 24 stage-III hips (83%) had a good or excellent result as determined by the Harris hip-scoring system. Two of six stage-IV hips (33%) had good or excellent results. Eighteen of 21 hips (86%) with a combined necrotic angle of 200° had good or excellent clinical results compared with only four of nine hips (44%) with a combined necrotic angle of more than 200°. Six of the eight hips which had fair or poor results were in patients who had received corticosteroids; five of these six hips had lesions with a combined necrotic angle of greater than 200° or were in a late stage (stage IV). There were no perioperative complications.

Our results suggest that the trapdoor procedure with autogenous cancellous and cortical bone grafting can be successful in Ficat and Arlet stage-III osteonecrosis of the hip in patients with small- to medium-sized lesions.

Limb salvage after loss of bone and soft tissue may require many operations to obtain soft-tissue cover and bony continuity. We describe a fibula-flexor hallucis longus osteomuscular flap which can provide both soft tissue and bone in a single stage. The flap is based on the peroneal vessels and is covered by a split-thickness skin graft.

We report the results in five patients with an average bone defect of 8.3 cm and soft-tissue and skin loss. All regained a normal gait on the donor side; four had clinical and radiological union with excellent soft-tissue cover, but one required later amputation due to diffuse coagulopathy.

The flap provides free vascularised bone with muscle cover. It has a dependable, long pedicle with minimal morbidity at the donor site, and allows monitoring of the vascularity of the fibular graft.

Posterior fixation of intervertebral discs is used to treat, and occasionally diagnose, discogenic pain since it is thought that it will reduce the internal loading of the discs in vitro. We measured the internal loading of ten intervertebral discs using stress profilometry under simulated physiological loads and then after posterior fixation. Partial discectomies were performed to simulate advanced disc degeneration and the sequence repeated.

Posterior fixation had very little effect on the magnitude of the loads acting on the disc and none when disc degeneration was simulated. It did, however, reduce bulging of the anterior annulus under combined bending and compression (p < 0.03). Recent experiments in vivo have shown that discogenic pain is associated with abnormal bulging of the annulus which suggests that the clinical benefit of fixation may be due to this.

We investigated the distribution of compressive ‘stress’ within cadaver intervertebral discs, using a pressure transducer mounted in a 1.3 mm diameter needle. The needle was pulled along the midsagittal diameter of a lumbar disc with the face of the transducer either vertical or horizontal while the disc was subjected to a constant compressive force. The resulting ‘stress profiles’ were analysed in order to characterise the distribution of vertical and horizontal compressive stress within each disc. A total of 87 discs from subjects aged between 16 and 87 years was examined.

Our results showed that age-related degenerative changes reduced the diameter of the central hydrostatic region of each disc (the ‘functional nucleus’) by approximately 50%, and the pressure within this region fell by 30%. The width of the functional annulus increased by 80% and the height of compressive ‘stress peaks’ within it by 160%. The effects of age and degeneration were greater at L4/L5 than at L2/L3, and the posterior annulus was affected more than the anterior. Age and degeneration were themselves closely related, but the stage of degeneration had the greater effect on stress distributions.

We suggest that structural changes within the annulus and endplate lead to a transfer of load from the nucleus to the posterior annulus. High ‘stress’ concentrations within the annulus may cause pain, and lead to further disruption.

We reviewed 11 patients (17 ankles) who had had core decompression for symptomatic avascular necrosis of the talus before collapse. The Mazur grading system was used to assess function preoperatively and at final follow-up, and radiographs were graded according to the Ficat and Arlet (1980) classification modified for the ankle.

At a mean follow-up of seven years (2 to 14) 14 ankles (82%) had an excellent or good outcome (Mazur scores > 80 points; pain scores > 40 points (41 to 50)). The other three ankles required tibiotalar fusion at a mean of 13 months (5 to 20) after core decompression.

We conclude that core decompression is a viable method of treatment for symptomatic avascular necrosis of the talus before collapse.

A case is reported in which fractures of the radius and ulna were fixed with Vitallium plates and screws. Seven years later a painful swelling appeared over the extensor aspect of the forearm. After eight years sarcoma was suspected and a pale tumour infiltrating muscle was found at operation. However, the histology excluded neoplasia and showed massive fibrosis and patchy necrosis of muscle, with chronic inflammatory changes peripherally. After the removal of the metal the swelling disappeared. A sinus down to the ulna followed operation and was not cured two years later. At this stage standard patch testing showed skin sensitivity to cobalt. Metal sensitivity is proposed as the cause of this extraordinary reaction in muscle.

1. Two cases of haemangioma of the patella are reported.

2. In one case pain alone brought the patient for treatment; in the other, a pathological fracture was the first symptom.

3. In neither case was a firm diagnosis made before excision and histological examination of the patella.

4. In each case a good result followed removal of the patella: this is probably the best method of treatment.

5. The literature relating to haemangioma of bone and to tumours of the patella is briefly reviewed.

Two cases of ganglion arising in the alar folds of the infrapatellar fat pad are reported. Both patients had symptoms of internal derangement of the knee, sufficient to justify operation.

1. A radiological study of the acromio-humcral interval in sixty normal shoulders and in fifty-nine shoulders with known tears of the rotator cuff is reported.

2. The normal acromio-humeral interval was found to be seven to fourteen millimetres, a range that is consistent with previous observations.

3. Narrowing of this interval is a frequent concomitant of a tear of the rotator cuff.

4. An interval of five millimetres or less should be considered compatible with a tear of the rotator cuff until proven otherwise.

5. An explanation of the pathomechanics of the observation has been proposed.

1. A total of 120 Moore's arthroplasties in 111 patients were reviewed one to nine years after operation.

2. There was striking reduction in the severity of pain in 105 out of the 120 hips reviewed. Range of movement was improved in most patients but the degree of independence was improved less often. The reasons for this are discussed.

3. We draw the following conclusions regarding the place of Moore's arthroplasty. Firstly, it was a natural step in the evolution towards total hip replacement, an operation which promises to give more complete relief of symptoms and which seems likely to replace Moore's arthroplasty as the treatment of choice in osteoarthritis of the hip in the elderly. Secondly, Moore's arthroplasty is still a rational procedure for the treatment of degeneration if the acetabulum is not involved—for instance, in idiopathic avascular necrosis of the femoral head. Thirdly, it is certainly a valuable operation for some cases of recent fracture of the femoral neck. Avascular necrosis of the femoral head after trifin nailing can be satisfactorily treated by Moore's arthroplasty, particularly in the early stages before the acetabulum becomes involved. Finally, Moore's arthroplasty gave many fairly elderly patients considerable relief of pain at a time when nothing better was available. Much of the relief afforded has proved to be lasting, but deterioration sometimes occurred with time. In the few patients whose deterioration amounted to failure a definite cause for the failure was found. In the majority the deterioration was slight, and it seems likely that the operation will last most of these elderly patients for the rest of their lives.

1. A case of total dislocation of the cuboid bone without fracture is described. This is an uncommon injury and to our knowledge has not previously been reported.

2. Its rarity is explained in the light of the structural anatomy and function of the foot.

3. A mechanism of injury is postulated and a method of reduction and fixation described.

I have tried to describe the functional attainments of amputees using conventional prostheses. I have outlined the work we have been doing on pneumatic arms for infants and children. I have discussed some of the practical problems in applying pneumatic and myo-electric systems to adults. The inescapable conclusion that one must reach is that two basic clinical requirements must be met before really significant advance is made in this field. Firstly, we must find a method of providing sensory information from the prosthesis. Secondly, we must find a way of utilising more control sites. So far we have only been able to make use of direct movements or myo-electric signals. In the high level bilateral subjects more controls are required than appear to be available. Capener has suggested, in more than one discussion that I can recall, the possibility of using the voice and I have no doubt that a subject could be trained to reserve certain frequencies for prosthetic controls. It may be that we will have to think along some such lines as this.

1. A case is described of fatigue fractures occurring in the lowest thirds of the right tibia and fibula simultaneously.

2. The fibular fracture was a runner's fracture.

3. The tibial fracture was ascribed to the application of a below-knee walking plaster to treat the fibular lesion.

4. Both fractures were slow in uniting.

5. The fractures occurred in a rapidly growing youth but no clinical evidence of an endocrine dysfunction was found.

1. Congenital defects of the extremities are described. Although the detailed anatomy is infinitely variable, a broad classification in relation to prosthetic management has been suggested.

2. Most patients with these deformities can be fitted with a prosthesis without major surgical intervention. With this they will have at least as good function as they would have after amputation. A plea is made for a conservative attitude in this respect. It is suggested that recourse to amputation should be confined to cases in which prosthetic equipment falls short of functional and cosmetic requirements, and that, when possible, it should be deferred until the child is old enough to share in the decision.

3. The prostheses applicable to the various types of deformity are briefly described.

4. The application of similar techniques to cases of acquired shortening is mentioned.

5. The incorporation of certain features of artificial arms in flail arm splints is discussed.