Osteoarthritis (OA) is a highly prevalent degenerative joint disorder characterized by joint pain and physical disability. Aberrant subchondral bone induces pathological changes and is a major source of pain in OA. In the subchondral bone, which is highly innervated, nerves have dual roles in pain sensation and bone homeostasis regulation. The interaction between peripheral nerves and target cells in the subchondral bone, and the interplay between the sensory and sympathetic nervous systems, allow peripheral nerves to regulate subchondral bone homeostasis. Alterations in peripheral innervation and local transmitters are closely related to changes in nociception and subchondral bone homeostasis, and affect the progression of OA. Recent literature has substantially expanded our understanding of the physiological and pathological distribution and function of specific subtypes of neurones in bone. This review summarizes the types and distribution of nerves detected in the tibial subchondral bone, their cellular and molecular interactions with bone cells that regulate subchondral bone homeostasis, and their role in OA pain. A comprehensive understanding and further investigation of the functions of peripheral innervation in the subchondral bone will help to develop novel therapeutic approaches to effectively prevent OA, and alleviate OA pain. Cite this article: Bone Joint Res 2022;11(7):439–452

Introduction The close proximity of the cutaneous and major nerves around the elbow have caused orthopaedic surgeons to feel uncomfortable about the prospect of performing basic and advanced elbow arthroscopy. The aim of this study was to review the proximity of the nerves with arthroscopic vision in a cadaveric model and selected clinical cases. Methods Open exploration of the major nerves in the elbow was performed in alcohol preserved cadaveric specimens. Arthroscopic assessment of the elbow joint was performed before and after the capsule adjacent to the nerve was excised. The arthroscopic assessment of the major nerves in these specimens provided an excellent way to visualise the nerves. Results The radial nerve was found to be in contact with the anterior capsule of the joint and was at great risk with portal placement, lateral sided procedures including synovectomy, radial head excision, capsulotmy and capsulectomy. The medial nerve was protected by the brachialis muscle. The ulnar nerve was also at risk in the medial gutter. Conclusions The close proximity of the major nerves to the elbow joint places them at risk, with elbow arthroscopy. The radial and ulnar nerves are particularly close and their exact position can be dissected free with arthroscopic techniques

Introduction. Severe ‘discogenic’ back pain may be related to the ingrowth of nerves and blood vessels, although this is controversial. We hypothesise that ingrowth is greater in painful discs, and is facilitated in the region of annulus fissures. Methods. We compared tissue removed at surgery from 22 patients with discogenic back pain and/or sciatica, and from 16 young patients with scoliosis who served as controls. Wax-embedded specimens were sectioned at 7μm. Nerves and blood vessels were identified using histological stains, and antibodies to PGP 9.5 and CD31 respectively. Results. Blood vessels were identified in 77% of ‘painful’ discs compared to 44% of scoliotic discs (p=0.013), and they were more common in the anterior anulus compared to the posterior (p=0.026). Maximum penetration of blood vessels from the peripheral anulus was 4.7 mm (in ‘painful’ discs) and 2.0 mm (in control discs), and penetration increased with histological grade of disc degeneration in the ‘painful’ discs (p=0.002). In 16/17 ‘painful’ discs, blood vessels were within 1 mm of an anulus fissure, or the disc periphery. Nerves were found in 36% of ‘painful’ discs (all with blood vessels) and 25% of control discs. Nerve ingrowth was always less than or equal to blood vessel ingrowth, with a maximum observed penetration of 1.5 mm from the annulus periphery. Discussion. In degenerated and painful discs, the ingrowth of nerves appears to follow that of blood vessels, and is facilitated in the region of annulus fissures. No nerves were seen >2mm from the annulus periphery, suggesting that previous reports of nerves in the disc nucleus may refer to vertical growth from a vertebral endplate rather than radial growth through the annulus. Results support the view that discogenic back pain is associated with pain-sensitisation events in the disc periphery. Acknowledgements. Research funded by BackCare. M Stefanakis would like to thank the Greek Institute of Scholarships (I.K.Y) for financial support

Introduction and Aims: The close proximity of the major nerves to the elbow places them at risk with elbow arthroscopy. New techniques of endoscopic ulnar nerve release, biceps bursoscopy and anterior elbow arthroscopy portal will be presented. Method: In a cadaveric model needles were used to transfix the major nerves to the elbow joint capsule. From an arthroscopic perspective the needles were located to assess the position of each nerve. Capsular windows were created to provide arthroscopic visualisation of each nerve. A technique of endoscopic ulnar nerve release using the Agee system will be presented including a cadaveric study assessing its safety. Endoscopic biceps bursoscopy will also be demonstrated. Results: The ulnar nerve passes on the postero-medial capsule and is at risk with debridement of the medial gutter. The radial nerve passes on the anterior-lateral capsule and is at risk during lateral portal placement, anterior capsular release, synovectomy and radial head excision. The median nerve passes anterior to the brachialis muscle and is protected. In a cadaveric model we were able to reproducibly perform a release of the arcade of Struthers, cubital retinaculum and Osborne’s FCU fascia with no injuries to the ulnar nerve or branches. Biceps bursoscopy can be performed for partial tears of the biceps tendon. Through the biceps bed an anterior elbow arthroscopy portal can safely be created. Conclusion: An understanding of the proximity radial and ulnar nerves allows elbow arthroscopy to be more safely performed. The endoscopic ulnar nerve release, biceps bursoscopy and anterior elbow arthroscopy portal are new techniques extending the therapeutic options

Aims: Multiple nerve repair by means of a Y-shaped nerve guide represents a good model for studying the specificity of peripheral nerve fiber regeneration. Here we have employed this model for investigating the specificity of axonal regeneration in mixed nerves of the rat forelimb model. Specificity of nerve regeneration can be defined as the ability of the nerve fibers of a peripheral nerve, after a lesion. Tree types of specificity on nerve regeneration has been postulated: “tissue specificity” (the preferential reinnervation of distal nerve tissue versus other types of tissue), topographic specificity (regenerating nerve fibers are preferentially attracted by analogous distal pathways (e.g. preferential regeneration along tibial nerve pathways by tibial nerve fibers), and end-organ specificity, which is the hypothesis that distal end-organs (muscle vs. sensory targets) specifically attracts the respective (motor vs. sensory) regenerating nerve fibers. Exists no agreement regarding the presence and features of the two last type of specificity. Methods: The left median and ulnar nerves, in adult female rats, were transected and repaired with a 14-mm Y-shaped conduit. The proximal end of the Y-shaped conduit was sutured to the proximal stump of either the median nerve or the ulnar nerve. Ten months after surgery, rats were tested for functional recovery of each median and ulnar nerve. Quantitative morphology of regenerated myelinated nerve fibers was then carried out by the two-dimensional disector technique. Results: Results showed that partial recovery of both median and ulnar nerve motor function was regained in all experimental groups. Performance in the grasping test was significantly lower when the ulnar nerve was used as the proximal stump. Ulnar test assessment showed no significant difference between the two Y-shaped repair groups. The number of regenerated nerve fibers was significantly higher in the median nerve irrespectively of the donor nerve, maintaining the same proportion of myelinated fibers between the two nerves (about 60% median and 40% ulnar). On the other hand, nerve fiber size and myelin thickness were significantly larger in both distal nerves when the median nerve was used as the proximal donor nerve stump. G-ratio and myelin thickness/ axon diameter ratio returned to normal values in all experimental groups. Conlusions: These results demonstrate that combined Y-shaped-tubulization repair of median and ulnar nerves permits the functional recovery of both nerves, independently from the proximal donor nerve employed, and that tissue, and not topographic, specificity guides nerve fiber regeneration in major forelimb mixed nerves of rats

Introduction. Discogenic pain is associated with ingrowth of blood vessels and nerves, but uncertainty over the extent of ingrowth is hindering development of appropriate treatments. We hypothesise that adult human annulus fibrosus is such a dense crosslinked tissue that ingrowth via the annulus is confined to a) peripheral regions, and b) fissures extending into the annulus. Methods. Disc tissue was examined from 61 patients (aged 37–75 yrs) undergoing surgery for disc herniation, degeneration or scoliosis. 5 µm sections were stained with H&E to identify structures and tissue types. 30 µm frozen sections were examined using confocal microscopy, following immunostaining for CD31 (an endothelial cell marker), PGP 9.5 and Substance P (general and nociceptive nerve markers, respectively). Fluorescent tags were attached to the antibodies. ‘Volocity’ software was used to calculate numbers and total cross-sectional area of labelled structures, and to measure their distance from the nearest free surface (disc periphery, or annulus fissure). Results. Maximum penetration of blood vessels and nerves from the peripheral annulus was 4,800 µm and 2,200 µm respectively. Maximum distance of nerves and vessels from the nearest free surface was 236 µm and 888 µm. Substance P (but not PGP 9.5) was co-localised with blood vessels, and both number and area of Substance P-stained structures were inversely correlated with grade of disc degeneration. Interpretation. Thick sections and fluorescent markers can show reliably where labelled structures are not present. Results therefore support our hypothesis: deep penetration of nerves into the human annulus occurs only if fissures are present. No conflicts of interest. No funding obtained. This abstract has not been previously published in whole or in part; nor has it been presented previously at a national meeting

Purpose: The purpose of this study was to establish the map of the motor branches of the median and ulnar nerves of the forearm and to count the Martin-Gruber anastomoses. Knowledge of anatomic variability would be useful for hyponeurotisation surgery of the spastic hand. Variations in the antebrachial emergence of the six motor branches of the medial nerve and the three motor branches of the ulnar nerve were studied. Material and methods: This study was conducted on twenty anatomic specimens obtained from five men and five women. We measured the length of the forearm and identified the origin of each motor branch of the medial and ulnar nerves using a horizontal line between the meidal and lateral epicondyles as the reference line. Results: Mean length of the forearm was 26.93±2.6 cm. Unlike the origin of the superior and inferior pronator teres nerves, and the palmaris longus, flexor carpi radialis, and flexor digitorum superficialis nerves which were very variable (coefficient of variation 49%–113%), the origin of the anterior interosseous nerve of the forearm (CV=39%) and its branches, and the flexor pollicis longus nerve and the flexor digitorum profondus nerves (CV =23% and 29% respectively) were much more regular. The superior and inferior origins of the flexor carpi ulnaris nerve were variable (CV = 157 and 22%) while the origin of the nerves for the deep flexor of the IV and V fingers showed a better coefficient of variation (13%). We observed four Martin-Gruber anastomoses (20%). Conclusion: This study demonstrated the wide anatomic variability of the medial and ulnar nerves both interin-dividually and intraindividually. Emergence of certain nerve branches appeared to be more regular, particularly the lower group of the median nerve and the anterior interosseous nerve of the forearm. It was however impossible to identify two groups exhibiting a statistically significantly greater frequency for the median nerve. The anatomic variations of the ulnar nerve were less pronounced. The inconsistency of the inferior flexor carpi ulnaris is noteworthy

The concept of non-anatomic reversed arthroplasty is becoming increasingly popular. The design medializes and stabilizes the center of rotation, and lowers the humerus relative to the acromion, and lengthens the deltoid muscle up to 18%. Such a surgically created global distraction of muscles is likely to affect nervous structures. When nerves are stretched up to 5–10%, axonal transport and nerve conduction starts to be impaired. At 8% of elongation, venous blood flow starts to diminish and at 15% all circulation in and out of the nerve is obstructed. [. 1. ] To understand nerve dynamics following reversed arthroplasty, we investigated nerve strain and excursion in a cadaver model. In a formalin-embalmed female cadaver specimen, the brachial plexus en peripheral upper limb nerves were carefully dissected and injected with an iodine containing contrast medium. At the same time 1.2 mm-diameter leaded markers were implanted at topographically crucial via points for later enhanced recognition on CT reconstructions. After the first session of CT scanning a plastic replica of the Delta reversed shoulder prosthesis® was surgically placed followed by re-injection of the plexus with the same solution. The preoperative and the postoperative specimen were studied using a helical CT scan with a 0,5 mm slice increment. The Mimics® (Materialise NV, Belgium) software package was used for visualization and segmentation of CT images and 3D rendering of the brachial plexus and peripheral nerves. After surgery, there was an average increase in nerve strain below physiologically relevant amplitudes. In a few local segments of the brachial plexus an increase in nerve strain exceeding 5–10 % was calculated. The largest increase in strain (up to 19%) was observed in a segment of the medial cord. These results suggest there might be a clinically relevant increase in nerve strain following reversed shoulder arthroplasty

Summary. Cytokines produced within the degenerate disc induce expression of neurotrophic factors and pain related peptides which could be important in nerve ingrowth and pain sensitisation leading to low back pain. The intervertebral disc (IVD) is considered the largest aneural and avascular structure within the human body, yet during degeneration vascularisation of the IVD is seen to be accompanied by nociceptive nerves. Low back pain is a highly debilitating condition affecting around 80% of the population, 40% of which are attributed to IVD degeneration. Discogenic pain was largely thought to be a result of irritation and compression of the nerve root, yet recent data suggests that pain may be attributed to the sensitisation of sensory nerves by the synthesis of pain related peptides, calcitonin gene related peptide (CGRP) and substance P. It is known that cytokines and chemokines produced by nucleus pulposus cells elicit various effects including the production of matrix degrading enzymes, and decreased matrix molecules. Here, we investigate the hypothesis that cytokines regulate both neurotrophic factor and pain related peptide synthesis within nucleus pulposus and nerve cells which may elicit algesic effects. Real-Time PCR was performed to investigate gene expression of the neurotrophic factors NGF, BDNF, NT3 and their receptors Trk A, B and C along with Substance P and CGRP on directly extracted RNA from human NP cells and NP cells cultured in alginate for 2 weeks prior to treatment for 48hours with IL-1, IL-6 or TNFα at 0–100ng/mL. Similarly SH-SY5Y neuroblastoma cells were differentiated in retinoic acid for 7 days prior to stimulation with IL-1, IL-6 or TNFα at 0ng/mL and 10ng/mL for 48hours. Immunohistochemistry was used to localise neurotrophic factor receptors Trk A, B and C in both degenerate discs and neuronal cells. NGF expression was present in normal and degenerate disc samples, however only degenerate discs expressed the high affinity receptor TrkA. Similarly Trk B was present in 22% of normal samples increasing to 100% expression within degenerate disc samples. All cytokines increased expression of NGF in NP cells (P≤0.05). TNFα also increased BDNF significantly, whereas no significant affects were seen in NT3 expression in NP cells. Trk B expression was significantly increased by IL-1 and TNFα treatment of NP cells. Conversely Trk C was down regulated by IL-6. Substance P was significantly increased by IL-1 and TNFα treatments whilst IL-6 and TNFα increased CGRP expression in NP cells. In SH-SY5Y cells, IL-1 significantly increased BDNF whilst IL-6 and TNFα failed to induce significant differences in neurotrophic factors. All cytokines increased Trk expression in the nerve cell line; however this failed to reach significance. Immunohistochemistry confirmed the presence of Trk receptors within the neuronal cell line. Here we have demonstrated that a number of cytokines known to be up regulated during disc degeneration and disc prolapse, induce expression of various neurotrophic factors, their receptors and pain related peptides within human NP cells, as well as SH-SY5Y cells. This data suggests that the presence and production of cytokines within the degenerate disc may be responsible for nerve ingrowth and sensitisation of nerves which may result in discogenic pain

Between 1988 and 1998, a total of 12 patients (6 men and six women, of average age 36 years) underwent surgery for schwannoma of the peripheral nerves of the upper extremity. The incidence according to the involved nerve was analyzed and the follow-up results and complications after surgical treatment were reviewed. The median nerve was most frequently involved (6 cases), followed by the ulnar nerve (4 cases) and the radial nerve (2 cases). The average duration of symptoms was 2 years (3 months-8 years). Pain or painful paresthesias were usually the main complains. None of the patients suffered from Recklinhausen’s disease. Magnetic resonance imaging is the preferred exploration technique, particularly useful in case of deep tumor. EMG studies were carried out in all patients. Preservation of nerve continuity is the underlying goal of the therapeutic strategy. Marginal excision was performed in all cases. The tumors were extricable displacing the nerve fiber bundles without penetrating into the bundle itself and it was possible thus to be resected without interrupting the nerve continuity. Postoperatively, 7 patients were pain free, while 5 improved. Neurological deficits were favourably influenced by the operation. Out of 4 patients with motor deficits 3 had complete and 1 had partial recovery. Three out of 6 patients with sensory deficits had complete recovery, 2 remained unchanged, while 1 worsened. One patient developed new motor and another one new sensory deficits. New deficits developed predominantly in patients with large tumorsor longstanding symptoms. There was no reccurence or malignant transformation until the average of 52 months of follow-up

Background. Fissures in the anulus fibrosus are common in disc degeneration, and are associated with discogenic pain. We hypothesise that anulus fissures are conducive to the ingrowth of blood vessels and nerves. Purpose. To investigate the mechanical and chemical micro-environment of anulus fissures. Methods. Six thoracolumbar spine specimens, comprising three vertebrae and two discs, were obtained from cadavers aged 68-83 yr. Discs were injected with blue dye to reveal the location of complete anulus fissures. Each specimen was then subjected to 1000 N compression, while intradiscal compressive stress was investigated by pulling a miniature pressure transducer through the disc, in planes likely to cross the anulus fissures. Some additional disc fragments were removed at surgery from patients with discogenic back pain, and examined histologically to gauge the concentration of collagen and proteoglycans within radial fissures, using a qualitative method. Results. Stress profiles were obtained perpendicular to major anulus fissures in seven discs. A marked local reduction in vertically-acting compressive stress usually coincided with fissure location (confirmed at dissection), and stress reductions were inversely proportional to average pressure in the nucleus (r. 2. =0.56, p<0.05). Surgical disc samples showed local depletion of proteoglycans around the margins of radial and circumferential fissures, leaving a collagen-rich scaffold of the type known to support nerve and blood vessel growth. Conclusion. Compressive stresses within anulus fissures are reduced most when the disc nucleus is decompressed, because this facilitates internal displacements of disrupted tissue. Anulus fissures provide a micro-environment that is mechanically and chemically conducive to the ingrowth of blood vessels and nerves

Purpose of the study: Benign tumors of peripheral nerves are exceptional. Schwannomas predominate. Most tumors are revealed by tumefaction or pain over a nerve trajectory. The risk of degeneration is very low. Magnetic resonance imaging is the exploration of choice. The risk of sequelae or recurrence must nevertheless be determined with precision. We reviewed our experience with 93 benign tumors of peripheral nerves to search for factors predictive of prognosis. Material and methods: This retrospective analysis included patients seen between 1979 and 2004. We collected a series of 89 patients, 41 women and 48 men, mean age 48 years, age range 18–80, with 93 benign tumors. Mean time from symptom onset (pain) to diagnosis was 20 months. The patients consulted for pain (n=78), presence of a mass (n=79) or both (n=66). Percussion produced paresthesia in 54 patients. Pre-operative magnetic resonance imaging was available for 45 patients. The same surgeon performed nerve microsurgery in all patients. A prior procedure had been performed in another institution for 23 patients. The tumors were: schwannoma (n=74), neurofibroma (n=14), plexiform neurofibroma (n=3), angiolipoma (n=1) and intranervous lipoma (n=1). Mean tumor size was 31 mm (range 7–120 mm). Tumors were located in the brachial plexus (n=13), the upper limb (n=29), the trunk (n=1) and the lower limb (n=50). Complete resection was achieved in 83 cases, with removal of a non-stimulatable fascicle in 50 cases and a motor fascicle in. 4. Nerve repair was required for 11 cases: 5 by direct suture and 6 with grafts. Resection was impossible for 4 tumors treated by neurolysis, decompressive epineu-rotomy, biopsy and interfascicular dissection. Results: Mean follow-up was 96 months (range 3–300). Outcome was very good for 42, good for 25, fair for 8 and poor for 5 (all seen secondarily). Nine patients were lost to follow-up. There were no cases of recurrence. Discussion: Microsurgical procedures are necessary for resection of nerve tumors in order to preserve the fascicles and thus function. Unresectable tumors and secondary grafts yield les satisfactory results, in our series and in the literature. Similarly, the duration of the symptoms and the size of the tumor increase the risk of operative difficulty and sequelae. Despite high-performance imaging techniques, surgery is the only sure way to establish certain diagnosis

Introduction: Increased cell senescence has been reported in the human intervertebral disc (IVD) and was associated with degenerative pathology, particularly herniation. Increased IVD innervation and blood vessel ingrowth is associated with disc degeneration and the development of back pain. This preliminary study examines whether there is a relationship between the prevalence of senescent IVD cells and the extent to which the tissue is innervated and/or vascularised. Methods: Specimens of herniated IVD (n=16 patients: aged 36–71) were stained for senescence associated β-galactosidase activity (SA β-gal), then snap frozen and cryosectioned prior to immunolocalisation procedures to detect nerves (NF200) or blood vessels (CD34). Stained sections were counterstained with DAPI to reveal cell nuclei. The proportion of SA β-gal +ve cells was scored and the extent of neural and blood vessel ingrowth semi-quantitated. Results: The proportion of SA β gal +ve IVD cells ranged from 6% – 91% (median=16%) and was significantly correlated with age. The degree of neural or blood vessel ingrowth ranged from tissue which contained numerous (i.e. ≥10) positive cells/cell processes to tissue which was completely aneural or avascular. However, there was no clear relationship between the presence of SA β-gal +ve IVD cells and IVD innervation or vascularisation. Conclusions: Cell senescence has been associated with up-regulated expression of catabolic enzymes, e.g. MMPs and increased synthesis of trophic cytokines, e.g. VEGF. Such cellular activity might by thought to contribute to the pathological ingrowth of nerves or blood vessels into the IVD. The data presented here, however, does not support such a hypothesis. Conflicts of Interest: None. Source of Funding: Institute of Orthopaedics, RJAH Orthopaedic Hospital

Solitary tumors of the peripheral nerves are uncommon and found to be benign in 90 p. 100 of the cases. They develop from the elements constituting the nerve and are generally schwannomas (80 p. 100). Other tumors are much more exceptional and exhibit wide histological variability. The diagnosis of a tumor of the peripheral nerve must be envisaged for all cases with tumefaction or pain on the path of a nerve exacerbated at percussion. Magnetic resonance imaging is the preferred exploration technique, particularly useful in case of a deep tumor. Preservation of nerve continuity is the underlying goal of the therapeutic strategy, irrespective of the type of tumor. Extricable tumors are to be distinguished from inextricable tumors. Extricable tumors (schwannomas, intranervous lipomas) displace nerve fiber bundles without penetrating into the bundle itself and can thus be resected without interrupting nerve continuity. Prognosis is excellent if no recurrence or degeneration occurs. In case of persistent symptoms, a new exploration may be required to search for other localized tumor(s) unperceived at the first procedure. Inextricable tumors (solitary neurofibromas, hemangiomas of the Schwann sheath, neurofibrolipomas) infiltrate the structural elements of the nerve fibers making complete excision impossible without altering the nerve fibers. Epineurotomy (associated with an interfascicular biopsy for pathology examination) allows decompression and can often provide symptom relief although moderate paresthesia may persist. Patients must be informed of this possibility prior to surgery. Any recent and rapidly evolving modification in the clinical findings is suggestive of recurrence and should be followed by revision exploration. Malignant degeneration has not been observed in solitary tumors to our knowledge. Our own experience with 51 cases is generally in agreement with reports in the literature

Aims: 1 To assess the histological changes in patients with Achilles tendinopathy. 2 To map the distribution of nerves and nerve endings within the Achilles tendon. Methods: Tendon biopsy specimens were taken from patients with spontaneous (ie previously painless) Achilles rupture patients and chronic painful tendinopathy patients. ‘Normal’ cadaveric /lacerated tendon biopsies were used for comparison. Sections were stained with H& E for basic histology. Immunolocalisation of nerve tissue was performed with 2 anti-neurofilament antibodies. Non-specific immunoglobulin was used as a negative control. Results: The number of nerves and nerve endings found within the normal tendons and both groups of degenerate tendons was very low. Only 30% of the normal tendon sections showed any positive staining at all. Compared to 36% of ruptured tendon and 43% of the painful tendinopathy sections. Conclusions: Tendon rupture and chronic painful tendinopathy biopsies ALL show widespread degenerative changes. There is a paucity of nerve tissue within these tendons, which may have implications for the neurogenic hypothesis of tendon degeneration. There appear be more nerve fibres in vascular areas of the painful tendinopathy biopsies. There may be more nerve fibres in the peritendinous tissue

Purpose: Isolated tumours of the peripheral nerves are exceptional and benign in 90% of the cases. They develop from the constitutive elements of the nerve and correspond to schwannomas in 80% of cases. Other tumours are much more rare and exhibit wide histological variability. Material and methods: Fifty-one patients were reviewed at mean 4.6 years. Forty-one had a resectable tumour: schwannoma (n=39), intranervous lipoma (n=2). Ten an unresectable tumour: solitary neurofibroma (n=5), peri-nervous hemangioma (n=3), neurofibrolipoma (n=2). We detailed the type of lesion, diagnostic elements, and results of complementary explorations. Enucleation was performed for resectable tumours. Epineurotomy for decompression with systematic interfascicular biopsy was performed in the event of an unresectable tumour. Results: Postoperative neurological deficits were exceptional and transient. In a first case, prognosis was excellent due to the absence of recurrence or degeneration. In the second, neurological disorders persisted but decreased (paraesthesia). The course remained stable. Discussion: Our findings are in line with reports in the literature. The diagnosis of nerve tumour should be entertained in the event of tumefaction along a nerve trajectory or if palpation triggers pain. MRI is the most powerful complementary exploration, particularly for deep tumours. The nature of the tumour, its benignity, and the possibility for resection can be suspected on the basis of clinical and complementary findings, but surgery and pathology examination of the surgical specimen are required for confirmation. Preservation of nerve continuity is the key to the therapeutic approach. For resectable tumours, exceptional persistence of symptoms should be followed by a new exploration to search for small unrecognised tumour(s) at the same operative site. For all other cases, recent and rapid changes in the clinical presentation is a sign of recurrence and requires appropriate intervention. To our knowledge, malignant degeneration has never been observed. Conclusion: First-intention resection of a nerve with a nerve tumour is never indicated

Introduction and aims

We present a series of patients who have had secondary reconstruction of war injuries to the upper and lower limbs, sustained during the Iraq and Afghanistan conflicts.

Introduction

We present a series of patients who have had secondary reconstruction of war injuries to the upper and lower limbs, sustained during the Iraq and Afghanistan conflicts.

Introduction: Guidelines for the management of LBP recommend diagnostic triage where most cases are classified ‘non-specific’, although studies have suggested this term is unsatisfactory to patients and practitioners. We aimed to describe the explanations for LBP used by general practitioners (GPs) and physiotherapists (PTs) in the UK.

Methods: Content analysis of an open question in a cross-sectional survey of GPs and PTs, based on a vignette of a patient with non-specific LBP. Respondents provided their explanation for the patient’s LBP in the language they would use with the patient. A coding schedule was developed (AB and NF) and applied to all data (AB).

Results: Survey response was 22% (n=446) for GPs and 55% for PTs (n=1091, 580 had seen a patient with LBP in the preceding 6 months were analysed). Responses to the open question were provided by 430 GPs and 560 PTs. Both professions used predominantly biomedical explanations (68% GPs, 51% PTs) such as tissue labels (e.g. ‘muscle’, ’disc’), ‘degeneration’ and ‘wear and tear’. PTs often gave lifestyle factors as reasons for LBP, with ‘work’ (19% PTs) and ‘posture’ (26% PTs) the most common. Only 2.8% of GPs and 6.4% of PTs would explain that the cause of LBP is unknown and use of the term ‘non-specific LBP’ was rare (0.9% GPs, 1.6% PTs).

Conclusion: Explanations for LBP used by GPs and PTs remain predominantly biomedical. The term ‘non-specific LBP’ is used very rarely. Further research needs to investigate appropriate language that explains non-specific LBP that is acceptable to both practitioners and patients.

Anatomically, bone consists of building blocks called osteons, which in turn comprise a central canal that contains nerves and blood vessels. This indicates that bone is a highly innervated and vascularized tissue. The function of vascularization in bone (development) is well-established: providing oxygen and nutrients that are necessary for the formation, maintenance, and healing. As a result, in the field of bone tissue engineering many research efforts take vascularization into account, focusing on engineering vascularized bone. In contrast, while bone anatomy indicates that the role of innervation in bone is equally important, the role of innervation in bone tissue engineering has often been disregarded. For many years, the role of innervation in bone was mostly clear in physiology, where innervation of a skeleton is responsible for sensing pain and other sensory stimuli. Unraveling its role on a cellular level is far more complex, yet more recent research efforts have unveiled that innervation has an influence on osteoblast and osteoclast activity. Such innervation activities have an important role in the regulation of bone homeostasis, stimulating bone formation and inhibiting resorption. Furthermore, due to their anatomical proximity, skeletal nerves and blood vessels interact and influence each other, which is also demonstrated by pathways cross-over and joint responses to stimuli. Besides those closely connected sytems, the immune system plays also a pivotal role in bone regeneration. Certain cytokines are important to attract osteogenic cells and (partially) inhibit bone resorption. Several leukocytes also play a role in the bone regeneration process. Overall, bone interacts with several systems. Aberrations in those systems affect the bone and are important to understand in the context of bone regeneration. This crosstalk has become more evident and is taken more into consideration. This leads to more complex tissue regeneration, but may recapitulate better physiological situations