Introduction

The purpose of this study was to examine trends in patient characteristics and clinical outcomes that occur with age as a statistical variable when performing autologous osteochondral transplantation (AOT) for the treatment of osteochondral lesions of the talus (OLT).

Aims

To establish if COVID-19 has worsened outcomes in patients with AO 31 A or B type hip fractures.

To assess implant performance, to evaluate fusion and to assess clinical and radiologic outcome of circumferential fusion using porous tantalum cages for ALIF in a 360-degree fusion.

A retrospective cohort study was performed over a 4-year period that included the implantation of 280 tantalum cages in 98 patients by the technique of anterior lumbar interbody fusion (ALIF) and posterolateral spondylodesis. Radiographic follow-up was performed to document any implant related problems. Preoperative and postoperative clinical outcome measures were assessed.

No neurological, vascular or visceral injuries were reported. There were no rod breakages and no symptomatic non-unions. One revision procedure was performed for fracture. Mean VAS back pain score in our patient cohort improved from 7.5 preoperatively to 1.9 at latest follow-up, mean VAS leg pain score improved from 6.2 to 1.1 and mean ODI score improved from 51.1 to 18.3.

Porous tantalum cages have high strength and flexibility, in addition to having similar biomaterial properties to cancellous bone. Their use in 360-degree spondylodesis to treat degenerative lumbar spine deformity has been demonstrated to be very safe and effective, with excellent clinical and functional outcomes.

To evaluate the incidence of complications and the radiographic and clinical outcomes from 2-stage reconstruction including 3-column osteotomy for revision adult spinal deformity.

A prospective cohort study performed over 2 years at a major tertiary referral centre for adult spinal deformity surgery. All consecutive patients requiring 2-stage corrective surgery for revision adult spinal deformity were included. Radiographic parameters and clinical outcome measures were collected preoperatively and at 6 weeks, 6 months, 1 year and 2 years postoperatively. Radiographic parameters analysed included pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis and sagittal vertical axis. Clinical outcome measures collected included EQ-5D, ODI, SRS 22 and VAS Pain Scores.

Performing anterior column reconstruction followed by 3-column osteotomy and extension of instrumentation for revision spinal deformity resulted an excellent correction of sagittal alignment, minimal surgical complications and significant improvements in HRQOL. Restoration of lumbar lordosis, pelvic tilt and sagittal vertical axis were observed in addition to postoperative improvements in EQ-5D, ODI, SRS 22 and VAS Pain Scores at follow-up.

Performing anterior column reconstruction prior to a 3-column osteotomy minimises complications associated with 3-column osteotomy and extension of posterior instrumentation. We propose a treatment algorithm for safe and effective treatment in revision adult deformity surgery.

To assess the clinical and radiologic outcome of MM patients with thoracic spine involvement and concomitant pathologic sternal fractures with a resultant severe sagittal plane deformity.

A prospective cohort study (n=391) was performed over a 7-year period at a national tertiary referral centre for the management of multiple myeloma with spinal involvement. Clinical, serological and pathologic variables, radiologic findings, treatment strategies and outcome measures were prospectively collected. Pre-treatment and post-treatment clinical outcome measures utilised included EQ-5D, VAS, ODI and RMD scoring systems.

13 MM patients presented with a severe symptomatic progressive sagittal plane deformity with a history of pathologic thoracic compression fractures and concomitant pathologic sternal fracture. All patients with concomitant sternal fractures displayed the radiographic features and spinopelvic parameters of positive sagittal malalignment and attempted clinical compensation. All patients had poor health related quality of life measures when assessed.

Pathologic sternal fracture in a MM patient with thoracic compression fractures is a risk factor for the development of a severe thoracic kyphotic deformity and sagittal malalignment. This has been demonstrated to be associated with a very poor health related quality of life.

To examine the impact of a structured rehabilitation programme as part of an integrated multidisciplinary treatment algorithm for adult spinal deformity patients.

A prospective cohort study was performed over a 2-year period at a major tertiary referral centre for adult spinal deformity surgery. All consecutive patients requiring 2-stage corrective surgery for sagittal malalignment were included (n=32). Details of physiotherapy initial evaluation, inpatient rehabilitation progress, details of bracing treatment and time to discharge were collected. Clinical outcome scores were measured preoperatively and at 6 weeks, 6 months and 1 year postoperatively.

After second stage corrective surgery, the mean time to standing without assistance was 2.1 days, mean time to independent ambulation was 4.2 days, mean time to competent ascending and descending stairs was 5.6 days and mean time to moulded orthosis application 7.1 days. Successful progression through the structured rehabilitation programme was associated with high clinical outcome scores and improved health related quality of life (HRQOL).

The introduction of this programme contributed to the development of an enhanced recovery pathway for patients having adult spinal deformity surgery, reducing inpatient length of stay and optimising clinical outcomes.

To evaluate the differences between spinopelvic parameters before and after sagittal malalignment correction and to assess the relationship between these radiologic parameters and clinical outcome scores.

A prospective cohort study was performed over a 2-year period at a major tertiary referral centre for adult spinal deformity surgery. All consecutive patients requiring 2-stage corrective surgery were included (n=32). Radiographic parameters and clinical outcome measures were collected preoperatively and at 6 weeks, 6 months, 1 year and 2 years postoperatively. Radiographic parameters analysed included pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis and sagittal vertical axis. Clinical outcome measures collected included EQ-5D, ODI, SRS 22 and VAS Pain Scores.

Correction of sagittal malalignment was associated with significant improvements in HRQOL. Restoration of lumbar lordosis, pelvic tilt and sagittal vertical axis correlated with postoperative improvements in EQ-5D, ODI, SRS 22 and VAS Pain Scores at follow-up.

This study demonstrates that the magnitude of sagittal plane correction correlates with the degree of clinical improvements in HRQOL. This further underlines the need for spinal surgeons to target complete sagittal plane deformity correction if they wish to achieve the highest rates of HRQOL benefit in patients with marked sagittal malalignment.

To assess screw malposition rates and complications associated with pedicle screw insertion using 3D navigation technology.

A retrospective study was undertaken for all cases where O-arm® and StealthStation® systems were used over a 2-year period. The primary outcome measure was return to theatre rates for pedicle screw malposition.

A total of 938 screws were inserted (934 thoracolumbar and 4 cervical), and 103 patients underwent spinal fixation using O-arm® and StealthStation® navigation. 64 were revision cases and 39 primary cases. Average number of levels was 4.6. There were a total of 10 complications: 3 infections, 1 DVT, 1 PE, 1 fast atrial fibrillation (AF), 1 screw malposition, 1 non-union, 1 undisplaced vertebral body fracture and 1 nerve root compression following osteotomy. The percentage return to theatre for screw malposition using 3D navigation was 1% of patients and 0.1% of pedicle screws. No patients developed permanent neurological compromise.

These systems provide accuracy that is comparable to traditional 2D fluoroscopic techniques. We advocate their use in the safe insertion of pedicle screws in complex revision deformity cases where original anatomical landmarks are absent or obscured. We also believe that radiation exposure is considerably less with navigation especially in these complex and revision cases.

To describe a staged surgical technique to correct significant progressive sagittal malalignment, without the need for 3-column osteotomy, in patients with prior long thoracolumbar instrumentation for scoliosis and to evaluate the radiographic and clinical outcome from this surgical strategy.

A small cohort study (n=6) of patients with significant sagittal malalignment following extensive thoracolumbar instrumented fusions for scoliotic deformity. Radiographic parameters analysed included pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis and sagittal vertical axis. Clinical outcome measures collected included EQ-5D, ODI, SRS 22 and VAS Pain Scores.

3 patients had 2-stage anterior release and instrumented fusion followed by a posterior instrumented fusion 3 patients with a large sagittal plane deformity had a 3-stage surgical technique. All patients achieved an excellent correction of sagittal alignment, with no surgical complications and excellent health related quality of life (HRQOL) outcome measures at follow-up. There was no symptomatic non-unions or implant failures including rod breakages.

We present a safe and effective surgical strategy to treat the complex problem of progressive sagittal malalignment in the previously instrumented adult deformity patient, avoiding the need for 3-column osteotomies in the lumbar spine.

The purpose of this study is to present a series of soft tissue sarcomas requiring complex vascular reconstructions, and to describe their management and outcomes.

Soft tissue sarcomas are rare mesodermal malignancies accounting for approximately 1% of all cancers diagnosed annually. Sarcomas involving the pelvis and extremities are of particular interest to the orthopaedic surgeon. Tumours that encase and invade large calibre vascular structures present a major surgical challenge in terms of safety of excision with acceptability of surgical margins. Technical advances in the fields of both orthopaedic and vascular surgery have resulted in a trend towards limb salvage with vascular reconstruction in preference to amputation. Limb-salvage surgery is now feasible due to the variety of reconstructive options available to the surgeon. Nevertheless, surgery with concomitant vascular reconstruction is associated with higher rates of complications including infection and amputation. We present a case series of soft tissue sarcomas with vascular compromise, requiring resection and vascular reconstruction. We treated four patients (n = 4, three females, and one male) with soft tissue masses, which were found to involve local vascular structures. Histology revealed leiomyosarcoma (n = 2) and alveolar soft part sarcomas (n = 2). Both synthetic graft and autogenous graft (long saphenous vein) techniques were utilised. Arterial reconstruction was undertaken in all cases. Venous reconstruction was performed in one case. One patient required graft thrombectomy at one month post-operatively for thrombosis.

We present a series of complex tumour cases with concomitant vascular reconstructions drawn from our institution's experience as a national tertiary referral sarcoma service.

Aims

Falls are a common occurrence among hospital inpatients and can lead to injury, prolonged hospitalisation and delayed rehabilitation. There is major economic burden associated with this. Post operative orthopaedic patients have certain risk factors that predispose them to falls including decreased mobility, use of opioids and, in some cases, history of previous falls.

Introduction

Osteoporosis is a common skeletal disorder characterised by a reduced bone mass and a progressive micro-architectural deterioration in bone tissue leading to bone fragility and susceptibility to fracture. With a progressively aging population, osteoporosis is becoming an increasingly important public health issue. The Wnt/β-catenin pathway is a major signalling cascade in bone biology, playing a key role in regulating bone development and remodelling, with aberrations in signalling resulting in disturbances in bone mass.

Introduction: Despite a resurgence in cobalt-chromium metal-on-metal arthroplasty and hip resurfacing, the potential toxicity of cobalt ions in the periprosthetic area remains a cause for concern. Cytotoxic effects have been demonstrated in macrophages with cobalt ions inducing apoptosis and TNF-α secretion. A similar cytotoxic effect has been demonstrated in osteoblast-like cells. However, these studies assessed the acute cellular response to cobalt ions over 48 hours. To date, the effect on osteoblasts of chronic exposure to cobalt ions is unknown.

Aim: In this study we investigated the effect on osteoblasts of chronic exposure to cobalt ions. Specifically we investigated the chemokine response and effect on osteoblast function. We also investigated for a change in osteoblast phenotype to a less differentiated mesenchymal cell type.

Methods. Primary human osteoblasts were cultured and treated with cobalt (10ppm) over 21 days. Secreted chemokines (IL-8, MCP-1, TNF-α) were assayed using enzyme-linked immunosorbent assays (ELISA). Osteoblast function was assessed via alkaline phosphatase activity and calcium deposition. For a change in osteoblast phenotype, osteoblast gene expression was assessed using real time PCR. Immunoflourescent cell staining of actin filaments was used to examine for a change in osteoblast morphology.

Results: Chemokine (IL-8) secretion by osteoblasts was significantly increased after 7 days of stimulation with cobalt ions. In parallel with this, osteoblast function was also significantly inhibited as demonstrated by reduced alkaline phosphatase activity and calcium deposition. Regarding osteoblast phenotype, FSP-1, CTGF and TGF-β gene expression were upregulated after 7 days exposure indicating a transition in osteoblast phenotype to a less differentiated mesenchymal cell type. Immunoflourescent staining of actin filaments also showed a change in osteoblast morphology. Taken together, these data demonstrate cobalt ions induce a change in the osteoblast phenotype to that of a mesenchymal cell type. This is the first study to investigate osteoblast plasticity in the context of periprosthetic osteolysis.

Conclusion: After prolonged exposure to cobalt ions, IL-8 chemokine secretion is increased which attracts neutrophils to the periprosthetic area. Furthermore, osteoblasts no longer function as osteogenic cells as demonstrated by a decrease in osteoblast alkaline phosphatase activity and calcium deposition. Instead, they undergo transition to a mesenchymal cell type as demonstrated by an increase in the expression of genes associated with a mesenchymal cell lineage. Instead of secreting osteoid matrix the new cell type secretes unmineralized collagen. Cobalt ions are not benign and may play an important role in periprosthetic osteolysis by inducing osteoblasts to undergo transition to a less differentiated mesenchymal cell type.

Osteoporosis is a common skeletal disorder characterised by a reduced bone mass and a progressive microarchitectural deterioration in bone tissue leading to bone fragility and susceptibility to fracture. The Wnt/β-catenin pathway is a major signaling cascade in bone biology, playing a key role in regulating bone development and remodeling, with aberrations in signalling resulting in disturbances in bone mass.

Our objectives were to assess the gene expression profile of primary human osteoblasts (HOBs) exposed to dexamethasone with a view to identifying key genes driving bone mass regulation and to assess the effects of the Wnt antagonist Dickkopf-1 (Dkk1) on the bone profile of primary human osteoblasts exposed in vitro to dexamethasone.

HOBs were cultured in vitro and exposed to 10–8M dexamethasone over a time course of 4hr, 12hr and 24hr. RNA isolation, cDNA synthesis, in vitro transcription and microarray analysis were performed. Microarray data was validated by quantitative real time RT-PCR. Dkk1 expression was silenced using small interfering RNA (siRNA). Quantitative RT-PCR was performed to confirm gene knockdown. Control and Dex-treated HOBs were compared with respect to bone turnover. Markers of bone turnover analyzed included alkaline phosphatase activity, calcium deposition, osteocalcin expression, along with cell proliferation and cellular apoptosis.

Global changes in HOB gene expression were elicited by dexamethasone.

Development associated gene pathways were co-ordinately dysregulated with the expression profile of key genes of the Wnt Pathway significantly altered. Dkk1 expression in HOBs was increased in response to dexamethasone exposure with an associated reduction in alkaline phosphatase activity, calcium deposition and osteocalcin expression. Silencing of Dkk1 expression, as confirmed by quantitative RT-PCR, was associated with an increase in alkaline phosphatase activity and calcium deposition, along with increased cell proliferation and reduced cellular apoptosis.

Dkk1 is an antagonist of Wnt/β-catenin signalling and plays a key role in regulating bone development and remodeling. Silencing the expression of Dkk1 in primary human osteoblasts has been shown to rescue the effects of dexamethasone-induced bone loss in vitro. The pharmacological targeting of the Wnt/β-catenin signaling pathway offers an exciting opportunity for the development of novel anabolic bone agents to treat osteoporosis and disorders of bone mass.

Introduction: Despite a resurgence in cobalt-chromium metal-on-metal arthroplasty, the potential toxicity of metal ions in the periprosthetic area remains a cause for concern. Studies to date have assessed the acute effect of cobalt ions on osteoblasts over 48 hours. The aim of our study was to determine the response of osteoblasts to cobalt ions over a prolonged period of exposure.

Methods. Primary human osteoblasts were cultured and treated with cobalt (10ppm) over 21 days. Osteoblast function was assessed via alkaline phosphatase activity and calcium deposition. ELISA were used to assess chemokine (IL-8, MCP-1 and TNF-α) secretion. Osteoblast gene expression was assessed using microarray analysis and real time PCR. Immunoflourescent cell staining of actin filaments was used to examine osteoblast morphology.

Results: Chemokine (IL-8) secretion by osteoblasts was significantly increased after 10 days of stimulation with cobalt ions. In parallel with this, osteoblast function was also significantly inhibited as demonstrated by reduced alkaline phosphatase activity and calcium deposition. Regarding osteoblast phenotype, FSP-1, CTGF and TGF-β gene expression were upregulated indicating a transition in osteoblast phenotype. Immunoflourescent staining of actin filaments also showed a change in osteoblast morphology. Taken together, these data show cobalt ions induce a change in the osteoblast phenotype to that of a mesenchymal cell type.

Conclusion: After 10 days of treatment with cobalt ions, osteoblasts no longer function as osteogenic cells. they undergo transition to a mesenchymal cell type. Furthermore, IL-8 secretion is increased which attracts neutrophils to the periprosthetic area thereby contributing to the inflammatory response that characterises osteolysis.

Aims: A retrospective review of all periacetabular osteotomies (PAO) performed at a general elective orthopaedic Hospital over a 7-year period. To assess the clinical, functional and radiographic outcome associated with PAO when introduced as a new procedure to a non-super-specialised regional centre.

Methods: A retrospective review of 85 PAOs performed on 79 patients at Cappagh Hospital between 1/4/1998 and 1/4/2005. The medical records and radiographic images of all patients were reviewed. Clinical follow-up evaluations were also performed.

Results: 85 PAOs were performed on 79 patients. Mean age at time of surgery was 22.9 years (range, 14–41 years) with an increased preponderance of females (F:M=10:1) and right sided hip involvement (R:L=1.1:1). The mean Merle D’Aubigne and Postel hip score increased from 12.4 (range 9–14) preoperatively to 16 (range 11–18) postoperatively (P< 0.0001). The average lateral center edge angle increased from 5° preoperatively to 26° postoperatively (P< 0.0001). The anterior center edge angle averaged 6.6° preoperatively and improved to 34.4° postoperatively (P < 0.0001). The acetabular index angle decreased from an average of 24.8° preoperatively to 8.4° postoperatively (P< 0.0001). At clinical follow-up, 77% of patients had no/mild pain, 30% of patients had a limp and 64% of patients were unlimited in physical activity.

Conclusions: The short term results in this group of patients treated with PAO show reliable radiographic correction of deformity and improved clinical scores. We suggest that PAO may safely be carried out at a non-super-specialized institution provided the surgeons have sufficient experience and patients are selected appropriately.

Introduction: Haematogenous pyogenic spinal infection encompasses spondylodiskitis, septic discitis, vertebral osteomyelitis and epidural abscess. Management of pyogenic spinal infection can involve conservative methods and surgical intervention. We carried out a retrospective review of 48 cases of pyogenic vertebral osteomyelitis presenting over a twelve-year period to the National Spinal Injuries Unit of the Republic Of Ireland. Our objective was to analyze the presentation, aetiology, management and outcome of 48 cases of non-tuberculous pyogenic spinal infection.

Methods: Both the Hospital Inpatient Enquiry (HIPE) System and the National Spinal Injuries Unit Database were used to identify our study cohort. The medical records, blood results, radiologic imaging and bacteriology results of all patients identified were reviewed.

Results: The average age of presentation was 59 years with an almost even distribution between males and females. Most patients took between three and six weeks to present to hospital. Diagnosis was confirmed by serological testing of inflammatory markers and radiological imaging. The most frequently isolated pathogen was Staph. aureus (75% of cases). 94% of cases were managed by conservative measures alone, including antibiotic therapy and spinal bracing. However, in 6% of cases surgical intervention was required due to neurological compromise or mechanical instability.

Conclusions: With this large cohort of non-tuberculous, pyogenic spinal infections from the NSIU, we conclude that Staph. aureus is the predominent pathogen. In the vast majority, conservative management with antibiotic therapy and spinal bracing is very successful. However in 6% of cases surgical intervention is warranted and referral to a specialist centre is appropriate.

Aims: Rugby is a popular sport in Ireland, with over 90,000 players registered with the Irish Rugby Football Union (IRFU) at all levels. We report a 10 year series of spinal injuries presenting to the National Spinal Injuries Unit (NSIU) at the Mater Misericordiae University Hospital.

Methods: A large series of spinal injuries in rugby players was isolated utilizing the NSIU database, HIPE and data from the IRFU. An extensive chart review and telephone interview was performed in all cases to determine age, mechanism of injury, possible aetiological factors, anatomic location of injury, American Spinal Injuries Association (ASIA) scores, current level of activity and response to rehabilitation.

Results: From 1994 to 2004, 22 rugby players with spinal injuries necessitated admission to the NSIU. Twelve patients (54%) presented with neurology. The average age at time of injury was 21.1 years (range 14 – 44 years) and all patients were male. The average length of hospital stay was 10.1 days (range 1 – 45 days). Twenty patients had cervical spine injuries. The most common mechanism of injury was hyperflexion of the cervical spine, with C5/C6 most commonly injured. Fifteen injuries occurred at adult level, the remainder at schoolboy level. Seventeen (77%) players were injured whilst playing First Team rugby. Eleven (50%) players were injured in the Backs, the remainder in the Forwards. 68% of injuries occurred in the tackle situation and 32% in the scrums, rucks and mauls. Winger, Full Back and Hooker were the playing positions at greatest risk.

Nine (41%) patients underwent surgery and 11 (50%) required rehabilitation in the National Rehabilitation Centre, Dun Laoghaire, with an average length of inpatient stay of 9.22 months (range 5 – 14 months). Eight (36%) patients felt that their injury was preventable. Of those patients without neurology, 60% have returned to playing rugby.

Conclusion: Rugby as a sporting pastime is not without risk. During the ten year period under review, 8 players suffered permanent disability as a direct result of participation in competitive rugby. Serious spinal injuries continue to occur and recent rule changes have had little effect in reducing their incidence.