Latest Advances in Robot-Assisted Knee Arthroplasty.

In the longstanding pursuit of improving alignment and functional outcome in knee arthroplasty, technological evolution leading to robotic systems has now been introduced to the mainstream orthopaedic surgical world. This technology facilitates greater accuracy in implant placement, protects soft tissues, and achieves better balancing, while also allowing the potential to be more bone conserving. Robots currently in use in orthopaedic surgery can be classified into passive or haptic semi-active surgeon-guided systems. Using a virtual model of the knee joint, the robot system guides bone cuts and facilitates precise implant placement. In addition, small changes to bone resection can be made permitting deformity correction and balancing. This is achieved on-table by dynamic referencing, which enables live objective measurement of range of movements, stability, and gap balance throughout the range of motion. Preservation of ligaments and their unnecessary releases has been shown to reduce time to recovery and allow potentially better knee kinematics. Advances in robot technology in knee arthroplasty have led to the development of a variety of systems to execute the multiple steps in this procedure including using computed tomography (CT) scans, magnetic resonance imaging (MRI) scans, plain radiographs (image based), or image-free systems. The combination of these images and on-table registering of bony landmarks allow the creation of a 3-dimensional (3D) virtual, but accurate, model of the knee during surgery. The various systems apply sculpting tools, burrs, or cutting saws to deliver the bone cuts or allow robots to guide placement of cutting blocks to ensure accurate pre-planned bone cuts. Intraoperative adjustments to bone resections can be made using a variety of tracker systems to measure joint movement and ligament balance to correct any malalignments while performing the surgery, so compound errors in the technique are avoided. Data from comparative studies suggest improved accuracy in implant placement in patients compared to conventional knee arthroplasty. Benefits of robot assistance have been demonstrated both in total knee arthroplasty and unicompartmental knee arthroplasty. Recent studies show a trend toward improved patient-reported outcomes and better patient satisfactions as well as earlier recoveries following robot-assisted knee arthroplasty. Early survivorship data has also shown a better survivorship with robot-assisted knee arthroplasty, although long-term survivorship data are awaited. An increase in familiarity, availability, and demand for this technology is driving innovations aimed at delivering a personalized approach to knee arthroplasty. This chapter will discuss the latest advances and look at the clinical research in relation to the robotic technological advancement comparing some of the different system approaches.

Isolated Cuboid-Lateral Cuneiform Coalition A Rare Cause of Foot Pain.

Tarsal coalitions represent a cohort of conditions characterized by bony, cartilaginous, or fibrous union of two or more tarsal bones. These disorders are often poorly understood by medical professionals, often leading to delays in diagnosis and treatment. They may be asymptomatic or cause hindfoot pain, stiffness, decreased range of motion, and foot deformities. Coalitions can be investigated by an ascending sequence of imaging including radiography, computed tomography, and magnetic resonance imaging. They may be managed conservatively with orthoses, activity modification, physiotherapy, anti-inflammatory medications, or definitive surgical intervention. To our knowledge, cuboid-lateral cuneiform coalition has not been reported in the orthopedic literature. We describe a 40-year-old woman with this condition who reported a 1-year history of left foot pain and stiffness. She was definitively diagnosed with magnetic resonance imaging and was managed conservatively with an aircast boot and hydrocortisone injection.

The role of electrical stimulation in the management of avascular necrosis of the femoral head in adults: a systematic review.

BACKGROUND: Avascular necrosis of the femoral head causes significant morbidity and occurs in up to 20,000 people per year. A variety of nonoperative and operative measures have been trialled however a definitive treatment algorithm is yet to be established. Young adults in many cases have undergone multiple surgical procedures in their lifetime with increasing risks of complications. Less invasive techniques may help reduce the number of operations required and positively influence the natural history of the disease process. Our aim was to navigate the literature and examine the results of electrical stimulation of the femoral head in avascular necrosis. METHODS: The following defined search strategy was used to perform a systematic review using MEDLINE and Google Scholar databases: ((avascular necrosis) OR (osteonecrosis)) AND (femoral head) AND ((electrical stimulation) OR (capacitive coupling) OR (pulsed electromagnetic fields)). Articles were reviewed and data compiled into tables for analysis. RESULTS: Fourty six articles were identified with a total of 10 articles meeting the inclusion criteria. 8 articles were prospective studies and 2 were retrospective. Early Ficat stages showed the best responses to treatment via pulsed electromagnetic fields with improvements in both clinical and radiographic parameters. Direct current and capacitative coupling have had a more ambiguous outcome. CONCLUSIONS: Pulsed electromagnetic fields may have a role in the management of early avascular necrosis. The paucity of clinical studies into this technique indicates a need for further studies.

Evidence for robots.

Robots have been successfully used in commercial industry and have enabled humans to perform tasks which are repetitive, dangerous and requiring extreme force. Their role has evolved and now includes many aspects of surgery to improve safety and precision. Orthopaedic surgery is largely performed on bones which are rigid immobile structures which can easily be performed by robots with great precision. Robots have been designed for use in orthopaedic surgery including joint arthroplasty and spine surgery. Experimental studies have been published evaluating the role of robots in arthroscopy and trauma surgery. In this article, we will review the incorporation of robots in orthopaedic surgery looking into the evidence in their use.

Nodular fasciitis of the masseter.

A 73-year-old man presented to ENT clinic with a painless, smooth lump overlying his right cheek. Fine needle aspiration wrongly diagnosed necrotising malignancy with squamous differentiation. MRI showed a lesion overlying the right masseter, and positron emission tomography scanning incorrectly suggested this was a metabolically active lymph node. After surgical excision, immunohistochemical analysis showed this was in fact nodular fasciitis of the masseter. Nodular fasciitis is a rare, benign, proliferative lesion whose clinical and histological features make it difficult to distinguish from malignancies such as sarcoma. Immunohistochemical analysis for markers including vimentin and actin is crucial for diagnosis. Without this, misdiagnoses are common and patients are at risk of unnecessarily aggressive treatment. This case report summarises the epidemiological, aetiological and clinical features of nodular fasciitis, explores the pitfalls of investigation modalities and describes its management.

Functional MRI brain imaging studies using the Contact Heat Evoked Potential Stimulator (CHEPS) in a human volunteer topical capsaicin pain model.

Acute application of topical capsaicin produces spontaneous burning and stinging pain similar to that seen in some neuropathic states, with local hyperalgesia. Use of capsaicin applied topically or injected intradermally has been described as a model for neuropathic pain, with patterns of activation in brain regions assessed using functional magnetic resonance imaging (fMRI) and positron emission tomography. The Contact Heat Evoked Potential Stimulator (CHEPS) is a noninvasive clinically practical method of stimulating cutaneous A-delta nociceptors. In this study, topical capsaicin (1%) was applied to the left volar forearm for 15 minutes of twelve adult healthy human volunteers. fMRI scans and a visual analog pain score were recorded during CHEPS stimulation precapsaicin and postcapsaicin application. Following capsaicin application there was a significant increase in visual analog scale (mean ± standard error of the mean; precapsaicin 26.4 ± 5.3; postcapsaicin 48.9 ± 6.0; P < 0.0001). fMRI demonstrated an overall increase in areas of activation, with a significant increase in the contralateral insular signal (mean ± standard error of the mean; precapsaicin 0.434 ± 0.03; postcapsaicin 0.561 ± 0.07; P = 0.047). The authors of this paper recently published a study in which CHEPS-evoked A-delta cerebral potential amplitudes were found to be decreased postcapsaicin application. In patients with neuropathic pain, evoked pain and fMRI brain responses are typically increased, while A-delta evoked potential amplitudes are decreased. The protocol of recording fMRI following CHEPS stimulation after topical application of capsaicin could be combined with recording of evoked potentials to provide a simple, rapid, and robust volunteer model to develop novel drugs for neuropathic pain.

The taylor spatial frame™ for correction of neglected fracture dislocation of the ankle.

Treatment of neglected fracture dislocations of the ankle poses a surgical challenge. Extensive open reduction can frequently be contraindicated because of local skin conditions and contractures. The Taylor Spatial Frame™ (TSF) has been used to reduce and maintain reduction of complex fractures. Its use in fracture dislocation of the ankle joint has not been described. We describe a case where a TSF was used to reduce and treat a 6-week-old fracture dislocation of the ankle. The TSF is a versatile device, which has a role in the management of both acute and neglected fractures.

Lateral clavicular autograft for repair of reverse hill-sachs defect.

Posterior dislocations of the shoulder joint can result in an impression fracture over the anteromedial humeral head, termed the reverse Hill-Sachs lesion, the presence of which can contribute to recurrent dislocations. Methods described to repair this defect include using allografts, iliac crest and coracoid process autografts, and bone graft substitutes. We describe a novel technique using the lateral end of the ipsilateral clavicle as an autograft in a 78 year old man with a reverse Hill Sachs lesion. This graft can be harvested through the same incision and does not compromise the stability of the acromioclavicular joint or any future shoulder arthroplasty.

Clinical trial of the p38 MAP kinase inhibitor dilmapimod in neuropathic pain following nerve injury.

Current treatments of neuropathic pain arising from conditions such as nerve injury/compression are only partially effective, and limited in their use by side-effects. p38 mitogen-activated protein kinase (MAPK) is involved in the regulation and synthesis of inflammatory mediators, and is the target for a novel class of cytokine-suppressive anti-inflammatory drugs. p38 inhibitors may reduce neuronal sensitisation in preclinical models of neuropathic pain, particularly where there is a substantial inflammatory component. An exploratory, multicentre, double-blind, placebo-controlled, two-period, cross-over trial was undertaken to evaluate the effect of dilmapimod (SB-681323), a selective p38 MAPK inhibitor, on neuropathic pain symptoms and signs. Fifty patients with nerve trauma, radiculopathy or carpal tunnel syndrome were randomised; 43 patients completed the study. Eligible patients received oral dilmapimod and placebo twice daily for 2 weeks, with an intervening washout period of 2-4 weeks. Subjects attended weekly for efficacy and safety assessments, which included evaluation of daily and current pain intensity using an 11-point numerical rating scale (NRS), quantitative sensory testing, allodynia and global impression of change. There was a statistically significant reduction in the primary endpoint of average daily pain score during the second week of treatment among patients treated with dilmapimod (15 mg/day) compared to placebo using NRS [0.80; 95% CI (0.28, 1.33); p=0.0034]. A similar trend for effect was seen in some secondary endpoints. Dilmapimod was well tolerated, with no clinically relevant safety findings. p38 MAPK inhibitors merit further evaluation for neuropathic pain in larger clinical trials, particularly for clinically meaningful analgesic effect size.

Age related incidence and early outcomes of hip fractures: a prospective cohort study of 1177 patients.

INTRODUCTION: Associated with the increase in the aging population, there is an increase in the incidence of hip fractures worldwide. Outcome following such fractures is affected by age of the patient. This study aims to assess the incidence and early outcome of hip fractures, comparing between different age groups. METHODS: Data of hip fractures collected over a period of five years was analysed. Patients were divided into three groups, group A (patients under the age of 64), group B (patients between 65 and 84 years of age), and group C (patients over the age of 85). RESULTS: Of the 1177 patients included in the study, there were 90 patients in group A, 702 patients in group B and 385 patients in group C. There was a female preponderance across all age groups, and this increased as age advanced (p < 0.0001). A significantly larger number of older patients lived alone and needed aids to walk before the injury (p < 0.0001). There was no significant difference in the type of fracture across the three groups (p = 0.13). A higher proportion of the elderly with intracapsular fractures were treated by replacement arthroplasty. Older patients who had internal fixation of intracapsular fractures had a better walking ability at 4 months. The overall deterioration in mobility was greater in older patients (p < 0.0001). Mortality was higher in older patients. CONCLUSIONS: Hip fractures are more common among females irrespective of age group. Older patients have a higher mortality and a greater deterioration of walking ability after such injuries. Internal fixation of intracapsular fractures have demonstrated satisfactory early outcome in the immediate period. This could be attributed to retention of native bone, better propioception and shorter operation time.

The time course of CO2 laser-evoked responses and of skin nerve fibre markers after topical capsaicin in human volunteers.

OBJECTIVE: To assess the temporal relationship between skin nerve denervation and regeneration (dermal and intra-epidermal fibres, IENF) and functional changes (CO(2) laser-evoked potentials, LEPs, and quantitative sensory tests, QST) after topical cutaneous application of capsaicin. METHODS: Capsaicin (0.075%) was applied to the lateral calf for three consecutive days. QST, LEPs and skin biopsies were performed at baseline and time intervals up to 54days post-capsaicin treatment. Biopsies were immunostained with antibodies for PGP9.5, TRPV1, and GAP-43 (marker of regenerating nerve fibres), and analyzed for IENFs and dermal innervation (for GAP-43). RESULTS: At 1day post-capsaicin, cutaneous thermal sensitivity was reduced, as were LEPs. PGP9.5, TRPV1, and GAP-43 immunoreactive-nerve fibres were almost completely absent. By Day 12, LEPs had fully recovered, but PGP9.5 and TRPV1 IENF continued to be significantly decreased 54days post-capsaicin. In contrast, dermal GAP-43 immunoreactivity closely matched recovery of LEPs. CONCLUSIONS: A good correlation was observed between LEPs and GAP-43 staining, in contrast to PGP9.5 and TRPV1. Laser stimulation is a non-invasive and sensitive method for assessing the initial IENF loss, and regenerating nerve fibres. SIGNIFICANCE: Assessing skin biopsies by PGP9.5 immunostaining alone may miss significant diagnostic and prognostic information regarding regenerating nerve fibres, if other approaches are neglected, e.g. LEPs or GAP-43 immunostaining.

Contact Heat Evoked Potentials Using Simultaneous Eeg And Fmri And Their Correlation With Evoked Pain.

BACKGROUND: The Contact Heat Evoked Potential Stimulator (CHEPS) utilises rapidly delivered heat pulses with adjustable peak temperatures to stimulate the differential warm/heat thresholds of receptors expressed by Adelta and C fibres. The resulting evoked potentials can be recorded and measured, providing a useful clinical tool for the study of thermal and nociceptive pathways. Concurrent recording of contact heat evoked potentials using electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) has not previously been reported with CHEPS. Developing simultaneous EEG and fMRI with CHEPS is highly desirable, as it provides an opportunity to exploit the high temporal resolution of EEG and the high spatial resolution of fMRI to study the reaction of the human brain to thermal and nociceptive stimuli. METHODS: In this study we have recorded evoked potentials stimulated by 51° C contact heat pulses from CHEPS using EEG, under normal conditions (baseline), and during continuous and simultaneous acquisition of fMRI images in ten healthy volunteers, during two sessions. The pain evoked by CHEPS was recorded on a Visual Analogue Scale (VAS). RESULTS: Analysis of EEG data revealed that the latencies and amplitudes of evoked potentials recorded during continuous fMRI did not differ significantly from baseline recordings. fMRI results were consistent with previous thermal pain studies, and showed Blood Oxygen Level Dependent (BOLD) changes in the insula, post-central gyrus, supplementary motor area (SMA), middle cingulate cortex and pre-central gyrus. There was a significant positive correlation between the evoked potential amplitude (EEG) and the psychophysical perception of pain on the VAS. CONCLUSION: The results of this study demonstrate the feasibility of recording contact heat evoked potentials with EEG during continuous and simultaneous fMRI. The combined use of the two methods can lead to identification of distinct patterns of brain activity indicative of pain and pro-nociceptive sensitisation in healthy subjects and chronic pain patients. Further studies are required for the technique to progress as a useful tool in clinical trials of novel analgesics.

Tumours of the hand presenting as pathological fractures.

Tumours represent one of the important differential diagnoses that need to be considered while investigating fractures of the small bones of the hand, as this can sometimes be the sole or the first presenting complaint. We conducted a retrospective study of the Scottish Bone Tumour Registry, analysing the records of patients with hand tumours which primarily presented as pathological fractures. The registry held records of 233 patients with tumours involving the bones of the hand, of which 53 (22.7%) had pathological fractures as the first presenting complaint. The average age at presentation was 36.9 yrs. The proximal phalanx was the most common bone involved (50.9%). The distal phalanx rarely developed pathological fractures due to tumours (5.3%). Most of the lesions affected the fifth ray (43.9%) Chondroma was the most common tumour seen (43 patients). Malignant lesions were an infrequent cause of pathological fractures (7 chondrosarcomas and 1 Ewing's sarcoma). Tumours are less commonly seen as a cause of fractures in the hand with most such fractures initially treated as minor injuries with buddy strapping and early mobilisation. A carefully obtained history and study of radiographs is essential to diagnose these lesions.

Endoscopic management of hypertensive intraventricular haemorrhage with obstructive hydrocephalus.

BACKGROUND: Intracranial haemorrhage accounts for 30-60 % of all stroke admissions into a hospital, with hypertension being the main risk factor. Presence of intraventricular haematoma is considered a poor prognostic factor due to the resultant obstruction to CSF and the mass effect following the presence of blood resulting in raised intracranial pressure and hydrocephalus. We report the results following endoscopic decompression of obstructive hydrocephalus and evacuation of haematoma in patients with hypertensive intraventricular haemorrhage. METHODS: During a two year period, 25 patients diagnosed as having an intraventricular haemorrhage with obstructive hydrocephalus secondary to hypertension were included in this study. All patients underwent endoscopic evacuation of the haematoma under general anaesthesia. Post operative evaluation was done by CT scan and Glasgow outcome scale. RESULTS: Of the 25 patients, thalamic haemorrhage was observed in 12 (48%) patients, while, 11 (44%) had a putaminal haematoma. Nine (36%) patients had a GCS of 8 or less pre-operatively. Resolution of hydrocephalus following endoscopic evacuation was observed in 24 (96%) patients. No complications directly related to the surgical technique were encountered in our study. At six months follow-up, a mortality rate of 6.3% and 55.5% was observed in patients with a pre-operative GCS of > or = 9 and < or = 8 respectively. Thirteen of the 16 (81.3%) patients with a pre-operative GCS >/= 9 had good recovery. CONCLUSION: Endoscopic technique offers encouraging results in relieving hydrocephalus in hypertensive intraventricular haemorrhage. Final outcome is better in patient with a pre-operative GCS of >9. Future improvements in instrumentation and surgical techniques, with careful case selection may help improve outcome in these patients.

Scaphoid fractures: variation in radiographic views - a survey of current practice in the West of Scotland region.

BACKGROUND: A variation seems to exist between hospitals with regard to the initial radiographic assessment of suspected scaphoid fractures. MATERIALS AND METHODS: A survey of all acute hospitals in the West of Scotland was carried out to ascertain the current practice in the assessment of acute scaphoid fractures. Consultant radiologists and consultant orthopaedic surgeons from the same hospitals were requested to suggest the minimum number and type of views to be ideally performed for a routine scaphoid series. RESULTS: Fourteen hospitals, 85 consultant orthopaedic surgeons and 60 consultant radiologists were contacted. Among the hospitals, 64.3% performed four views and 28.5% performed three views for a suspected scaphoid fracture. The commonly performed radiographs were lateral with the wrist neutral (85.7%) and postero-anterior oblique in ulnar deviation (78.5%). Of the consultant orthopaedic surgeons, 57.5% suggested four views, while 33.3% suggested three views. A lateral view with the wrist neutral (87.8%) and a postero-anterior view in ulnar deviation (51.5%) were considered most useful. Of the consultant radiologists, 68.4% suggested four views and 15.8% suggested three views. A lateral view with the wrist neutral (84.2%) and a postero-anterior view in ulnar deviation (52.6%) were considered most useful. DISCUSSION: A lack of uniformity is found among orthopaedic consultants who request scaphoid views, radiographers who perform the views and radiology consultants who report on these. We feel a uniform system of radiographic evaluation of scaphoid fractures should be introduced, with a standardized number and type of views, in all hospitals to increase the familiarity of both terminology and visualization.