Management of glenoid bone loss with impaction and structural bone grafting in reverse shoulder arthroplasty

INTRODUCTION

Glenoid bone loss is a commonly encountered problem in complex primary and revision shoulder arthroplasty. Addressing glenoid bone loss is critical to avoid complications like early loosening, impingement, notching and instability. A large number of techniques like bone grafting using autograft or allograft, eccentric reaming, augmented base plates, patient-specific instrumentations and custom-made implants are available to tackle bone loss.

MATERIALS AND METHODS

We prospectively collected the data of all patients with glenoid defects undergoing primary or revision reverse shoulder replacement between 2004 and 2017. This included demographic data, ranges of motion, Constant-Murley score and Subjective Shoulder Value (SSV). A pre-operative CT scan was done as well to plan the surgery and calculate the glenoid version. At each follow-up, the clinical function and shoulder scores were assessed. Additionally, the radiographs were assessed for graft incorporation, evidence of lysis and calculation of glenoid version.

RESULTS

Between 2004 and 2017, 37 patients underwent glenoid bone grafting during reverse shoulder arthroplasty. Average age was 72 years (range 46-88). Indications for surgery were cuff tear arthropathy (6 patients); revision of failed other prosthesis (23); primary osteoarthritis (4); rheumatoid arthritis (3); and second-stage revision for infection (1). The glenoid defect was contained in 24 patients, and therefore, impaction graft with a combination of bone graft substitute and/or humeral head autograft was performed. In 13 patients the glenoid defect was severe and uncontainable and therefore a graft-implant composite glenoid was implanted using humeral head autograft or allograft. Average follow-up was 3.6 years (range 1-10). Mean Constant score improved from 34 before surgery to 63 after surgery. Mean SSV score improved from 0.9/10 to 8.3/10. Active movements improved significantly with forward elevation increasing from 54° to 123°; abduction from 48° to 123°; external rotation from 24° to 38°; internal rotation from 57° to 70°. Radiographs at final follow-up showed no radiolucencies around the glenoid component and no evidence of loosening of the implant. In 2 cases there was a grade I notching. There was 100% survivorship at the last follow-up.

CONCLUSION

Impaction bone grafting along with structural grafting when required is an effective and reproducible way of managing severe glenoid bone loss. This technique gives consistent and good clinical and radiological results.

The "purse string" technique for anterior glenohumeral instability: long-term results 7-13-year follow-up

PURPOSE

The "Purse-String Technique" (PST) is an arthroscopic horizontal mattress suture technique for recurrent anterior shoulder instability that uses a single double-loaded suture anchor at the 4-o' clock position, achieving a Bankart labral repair and an infero-superior capsular shift. In this study, we describe the long-term results of the PST.

METHODS

The study included 69 individuals (70 shoulders), with a mean age of 30 years, who had recurrent post-traumatic anteroinferior instability. A purse-string suture anchor at the 4-o'clock position was used to address the Bankart lesion and capsular laxity, recreating the anterior glenoid bumper. All patients were assessed via telephone interview at a mean of 116 months after surgery (7-13-year follow-up).

RESULTS

Postoperatively, the mean Constant score was 94, mean Rowe score was 93 and mean Walch-Duplay score was 89. 89% of patients resumed their preinjury sport activities, with 61% of patients achieving preinjury levels and most professional athletes returning to full activity. Seven patients had recurrent dislocation postoperatively (10% failure rate). Of these patients, three had revision arthroscopic stabilization, one patient had revision arthroscopic stabilization with remplissage, two had a Latarjet procedure, whereas one patient decided to seek no further treatment.

CONCLUSION

The long-term results of PST are promising, with a low failure rate, high patient satisfaction and a high rate of return to sport.

LEVEL OF EVIDENCE

Level IV; Case series; Treatment study.

Acute versus delayed reverse total shoulder arthroplasty for proximal humeral fractures: a consecutive cohort study

BACKGROUND

The treatment of displaced proximal humeral fractures (PHFs) remains controversial. Open reduction-internal fixation (ORIF) can be challenging, especially in elderly patients with poor bone quality, whereas hemiarthroplasty has had unpredictable outcomes. Conservative treatment may result in severe fracture sequelae with poor outcomes, requiring late reverse total shoulder arthroplasty (RTSA) in many cases. The past few years have seen a shift toward the use of RTSA for the treatment of PHFs. The aim of this study was to compare the outcomes of RTSA between patients with acute fractures and patients who underwent delayed RTSA for fracture sequelae. Our hypothesis was that the outcomes of RTSA for acute PHFs would be better than those of delayed RTSA for fracture sequelae.

METHODS

We followed up 36 patients with a mean age of 79.1 years who underwent primary RTSA for acute PHFs and 56 patients with a mean age of 72.1 years who underwent RTSA in delayed fashion for fracture sequelae, including failed ORIF. The minimum follow-up period was 24 months. The mean follow-up period was 39.3 months in the acute RTSA group and 56.6 months in the delayed RTSA group. Demographic data, radiographs, and surgery data were prospectively collected and analyzed. At final follow-up, range of motion and radiographic analysis findings, as well as the Subjective Shoulder Value (SSV) and Constant score (CS), were recorded.

RESULTS

The clinical results favored the group undergoing acute RTSA for acute PHFs, with a mean SSV of 8.3 of 10 and adjusted CS of 88.9% compared with a mean SSV of 8.0 of 10 and adjusted CS of 77.6% in the group undergoing late RTSA for fracture sequelae-but without statistically significant differences between the groups. Although the acute RTSA group showed slightly better range-of-motion values, no statistically significant differences were found between the groups. No intraoperative complications occurred. The time from injury to the regaining of good pain-free function was significantly shorter in the acute RTSA group.

CONCLUSION

Although there were no statistically significant differences in outcomes between early RTSA for acute PHFs and late RTSA for fracture sequelae, the time from injury to the regaining of good pain-free function was significantly shorter in the acute RTSA group. Therefore, we advocate early RTSA for acute PHFs in elderly patients to provide a quicker recovery and an early return to good predictable outcomes with a much shorter period of pain and discomfort. In cases of failed conservative treatment, malunion, or failed ORIF, salvage RTSA has the potential to provide a good outcome.

Survival of monoblock RM vitamys compared with modular PINNACLE cups: mid-term outcomes of 200 hips performed by a single surgeon

INTRODUCTION

Monoblock cups have theoretical advantages over modular cups; however, their superiority in terms of survival has not been confirmed in comparative studies.

METHODS

We compared the mid-term survivorship of 107 RM Pressfit vitamys monoblock cups (Mathys Ltd., Bettlach, Switzerland) with 93 modular pressfit Pinnacle cups (DePuy Synthes, Warsaw, IN, USA). All cases were registered in the Arthroplasty Registry Thessaloniki and performed by a senior surgeon through the same approach between 2013 and 2014. The groups were comparable in sex distribution, preoperative diagnosis, follow-up, cup diameter, head diameter, type and use of screws, HOOS and HSS preop scores; the recipients of RM cup were significantly younger.

RESULTS

3 sockets were revised. The 6-year survival for any reason was 99.1% for the RM and 97.8 % for the PINNACLE group. There was no difference in survival for aseptic loosening and any reason between groups (log-rank test p = 0.921 and p = 0.483, respectively). The age (95% CI, 0.79-1.1), sex (95% CI, 0.2-45.0), cup diameter (95% CI, 0.18-1.1), head diameter (95% CI, 0.004-6.2), preoperative diagnosis and use of screws (95% CI, 0.02-4.3), did not influence hazard ratio for revision between groups. HHS and HOOS were comparable at the last follow-up.

CONCLUSIONS

Our study demonstrated that both cup designs had similar revision rates at mid-term follow-up, regardless the fact that the RM vitamys was used in a cohort of younger patients; which according to the literature would have led to earlier failures. Further long-term data are needed to evaluate the superiority of RM vitamys in the clinical setting, especially in the young.

Minimally invasive fixation with modified palm tree technique for proximal humerus fractures: Outcomes in a series of 132 patients

INTRODUCTION

Various surgical techniques and implants are available for surgical treatment of significantly displaced proximal humerus fractures. We describe a minimally invasive technique using 3 curved wires, inserted in a retrograde fashion into the humeral head. These are aimed to diverge within the humeral head to provide three separate 3-point fixations to achieve good stability. We present the results of proximal humerus fractures managed with the modified palm tree technique.

METHODS

A retrospective analysis of data collected prospectively including demographics, radiographs, clinical outcomes, complications and revision surgery for patients treated with the palm tree technique was performed.

RESULTS

Between 1998 and 2017, 132 patients underwent fixation with this technique. Average age was 61.8 years. Fifty-Eight fractures were 2 part, 46 were three part and 28 were four part. Average follow up was 26 months. In three to four part fractures, a bone graft substitute block was used behind the humeral head fragment for structural support. There were 11 early revisions (8.3%). In 7 cases the fixation failed early and was revised to other implants like angular & locking plates (4), hemiarthroplasties (2) and reverse arthroplasty (1). In 4 cases the construct was revised to achieve better positioning of the wires. From the 125 remaining patients, 120 achieved union(96.8%). There were 3 painless fibrous non-unions and 2 painful non-unions requiring revision. The mean final Constant score was 75.5 and subjective shoulder value was 7.8/10. Nine patients (6.8%) developed avascular necrosis of the humeral head of which three patients were revised later to an arthroplasty.

CONCLUSION

This technique is a simple, minimally invasive technique which can be used for two, three and four part fractures with good functional outcomes and high union rates. No metalwork remains in the proximal humerus should another procedure like arthroplasty be required in case of avascular necrosis of the humeral head or fracture sequela.

Total hip arthroplasty in patients with slipped capital femoral epiphysis: a systematic analysis of 915 cases

There is limited evidence on the outcomes of Total Hip Arthroplasty (THA) in Slipped Capital Femoral Epiphysis (SCFE) patients. This systematic review aims to evaluate the current literature in terms of survival rate, functional outcomes, complications and types of implants of THA in SCFE patients. Following the established methodology of PRISMA guidelines, PubMed, Cochrane library, ScienceDirect and Ovid MEDLINE were systematically searched from inception to September 2018. The search criteria used were: (“total hip arthroplasty’’ OR ‘’total hip replacement’’ OR “hip arthroplasty’’ OR ‘’hip replacement’’) AND (‘’slipped capital femoral epiphysis’’ OR ‘’slipped upper femoral epiphysis’’ OR ‘’femoral epiphysis’’). Ten studies were finally included in the analysis and were qualitatively appraised using the Newcastle-Ottawa tool. Variables were reported differently between studies. The sample size varied from 12 to 374 THAs. A total of 877 patients undergone 915 THAs. The mean reported follow-up ranged from 4.4 to 15.2 years and the mean patients’ age at the time of THA from 26 to 50 years. Four studies specified the type of implants used, with 62% being uncemented, 24% hybrid (uncemented cup/cemented stem) and 14% cemented. All but three studies reported the mean survival of implants that ranged from 64.9% to 94.8%. A limited number of complications were mentioned. There was a tendency for more favorable functional outcomes in modern studies. Modern THA-studies in SCFE patients showed improvement of survivorship, clinical outcomes and patient satisfaction. Future higher-quality studies are necessary to estimate long-term postoperative outcomes better.

Association of Polymorphisms in the Promoter Region of NOS2A Gene with Primary Knee Osteoarthritis in the Greek Population

Introduction

A new emerging role of nitric oxide (NO) in the aetiology of osteoarthritis (OA) has been reported. Inducible NO synthase (iNOS), produced by chondrocytes, is the major source of NO in the osteoarthritic cartilage. The aim of this study is to evaluate the potential association between the -1173C/T (rs9282799), -1026 C/A (rs 2779249) and -954G/C (rs1800482) single nucleotide polymorphisms (SNPs) in the promoter of the iNOS gene (NOS2A) and the incidence of knee OA in Greek population.

Methods

Ninety-six patients with primary knee OA were included in the study along with 44 controls. Genotypes were identified using polymerase chain reaction (PCR) and DNA sequencing techniques. Allelic and genotypic frequencies were compared between patients and controls.

Results

None of the -1173C/T, -1026 C/A and -954G/C SNPs were detected in the studied population, either in patients or controls. However, another SNP was identified at the site -1056 at the promoter region, where the initial G allele was substituted by the T allele. Interestingly, the TT genotype was completely absent in controls, but was detected in six patients with a 6.2% observed frequency. The difference between patients and controls was not statistically significant (p-value = 0.18). In male OA patients, the observed frequency of the TT genotype was higher (28.6%) in comparison to the 0% of the male controls (p-value = 0.1). The frequency of the G allele was 0.82 in controls and 0.78 in OA patients (p-value = 0.53).

Conclusions

The present study demonstrates that the 954G/C, -1026C/A, -1056G/T and -1173C/T SNPs of the NOS2A gene are not a risk factor for primary knee OA in Greek population. Moreover, -954G/C, -1026C/A and -1173C/T are rare, if not completely absent, in the Greek population. Additional research is mandatory in order to investigate the association of these SNPs with OA in different ethnic populations.

Reverse shoulder arthroplasty with a cementless short metaphyseal humeral prosthesis without a stem: survivorship, early to mid-term clinical and radiological outcomes in a prospective study from an independent centre

INTRODUCTION

The use of reverse total shoulder arthroplasty has increased for the management of cuff-deficient glenohumeral joint arthritis and fractures. With bone preservation being a major target in reverse shoulder arthroplasty, metaphyseal humeral components without a stem were developed. The aim of this study is to present the survivorship, functional and radiological outcomes of a novel short metaphyseal prosthesis without a diaphyseal stem from an independent centre.

METHODS

Clinical function and radiological features of patients undergoing stemless reverse shoulder arthroplasty were prospectively recorded. Patients' demographics, indications for surgery, complications, functional and radiological assessment at the final follow-up as well as survivorship with the end point of revision for any reason were recorded.

RESULTS

Between 2009 and 2016, 36 patients received 37 reverse shoulder arthroplasties with the stemless Verso prosthesis. Mean age of the patients was 76.9 years. The most common indication for surgery was cuff tear arthropathy. Mean follow-up was 3 years (range 1-7 years). Oxford shoulder score improved from an average of 11 pre-operatively (range 2-19) to 44 post-operatively (range 29-48) (p < 0.0001). There was one case of a deep post-operative infection that needed washout, liner exchange with retention of the prosthesis. Radiographic analysis showed no lucencies, or stress shielding around the humeral or glenoid components. Constant score at the final follow-up was on average 63 (range 35-86). Activities of daily living with requirement for internal and external rotation score (ADLEIR) was on average 12 pre-operatively (range 0-27) and 31 post-operatively (range 18-36) (p < 0.0001). There was 100% survivorship of the prosthesis in this early to mid-term study.

CONCLUSION

This early to mid-term prospective study demonstrates excellent survivorship and radiological results of the Verso reverse shoulder replacement. It needs a simple reproducible technique, and the results have been replicated at an independent centre. This study underlines its survivorship in the early to mid-term and confirms lower incidence of complications such as instability, notching, loosening and the need for revision surgery. Most importantly, it conserves the humeral bone stock for revision arthroplasties in the future. Our results are similar to those of the currently published literature.

Inducible nitric oxide synthase as a target for osteoarthritis treatment

INTRODUCTION

Inducible nitric oxide synthase (iNOS) is the enzyme responsible for the production of nitric oxide (NO), a major proinflammatory and destructive mediator in osteoarthritis (OA). Areas covered: This is a comprehensive review of the recent literature on the involvement of iNOS in osteoarthritis and its potential to be used as a target for OA treatment. Evidence from in vitro, in vivo and human studies was systematically collected using medical search engines. Preclinical studies have focused on the effect of direct and indirect iNOS inhibitors in both animal and human tissues. Apart from direct inhibitors, common pharmacological agents, herbal and dietary medicines as well as hyperbaric oxygen, low level laser and low intensity pulsed ultrasound have been shown to exhibit a chondroprotective effect by inhibiting the expression of iNOS. Expert opinion: Data support the further investigation of iNOS inhibitors for the treatment of OA in human studies and clinical trials. Indirect iNOS inhibitors such as interleukin 1 inhibitors also need to be studied in greater detail. Finally, human studies need to be conducted on the herbal and dietary medicines and on the non-invasive, non-pharmacological treatments.

Results from the surgical resection of severe heterotopic ossification of the hip: a case series of 26 patients

INTRODUCTION

Surgical resection of heterotopic ossification (HO) around the hip joint is often challenging. The aim of this study is to evaluate the clinical and radiological outcomes following surgical resection of Brooker's type III and IV HO of the hip.

METHODS

We retrospectively reviewed clinical and radiological data, between November 2006 and January 2013, of all patients who underwent surgical resection of severe HO of the hip. Brooker's grading, range of motion and the Harris Hip Score before and after surgery were recorded in all cases. The combined radiation (700 cGy preoperatively) and indomethacin regimen was used to prevent heterotopic ossification recurrence.

RESULTS

Twenty-six patients (22 males and 4 females) were included in our study. Mean patient age was 47.38 years (range 24-72). The HO was graded as Brooker grade III in 3 patients (11.5%) and Brooker grade IV in 23 patients (88.5%). Mean time interval between HO development and resection was 40.8 months (range 13-156 months). All patients had CT scans prior to surgery. Mean follow-up was 31.4 months (range 24-40 months). There was no severe HO recurrence. Complications included one intraoperative injury of a femoral artery branch, one intraoperative femoral neck fracture treated with intramedullary nailing, one sciatic nerve injury and one superficial infection treated conservatively.

CONCLUSIONS

Surgical resection of severe HO of the hip along with preoperative radiation and indomethacin provides excellent results; however, the complication rate is relatively high. Careful evaluation of the preoperative CT scan and wide exposure are required in order to identify all the involved neurovascular structures.

Recurrent missense mutation of GDF5 (p.R438L) causes proximal symphalangism in a British family

Proximal symphalangism (SYM1B) (OMIM 615298) is an autosomal dominant developmental disorder affecting joint fusion. It is characterized by variable fusions of the proximal interphalangeal joints of the hands, typically of the ring and little finger, with the thumb typically being spared. SYM1 is frequently associated with coalition of tarsal bones and conductive hearing loss. Molecular studies have identified two possible genetic aetiologies for this syndrome, NOG and GDF5. We herein present a British caucasian family with SYM1B caused by a mutation of the GDF5 gene. A mother and her three children presented to the orthopaedic outpatient department predominantly for feet related problems. All patients had multiple tarsal coalitions and hand involvement in the form of either brachydactyly or symphalangism of the proximal and middle phalanx of the little fingers. Genetic testing in the eldest child and his mother identified a heterozygous missense mutation in GDF5 c.1313G>T (p.R438L), thereby establishing SYM1B as the cause of the orthopaedic problems in this family. There were no mutations identified in the NOG gene. This report highlights the importance of thorough history taking, including a three generation family history, and detailed clinical examination of children with fixed planovalgus feet and other family members to detect rare skeletal dysplasia conditions causing pain and deformity, and provides details of the spectrum of problems associated with SYM1B.

Application of Far Cortical Locking Technology in Periprosthetic Femoral Fracture Fixation: A Biomechanical Study

BACKGROUND

Lack of fracture movement could be a potential cause of periprosthetic femoral fracture (PFF) fixation failures. This study aimed to test whether the use of distal far cortical locking screws reduces the overall stiffness of PFF fixations and allows an increase in fracture movement compared to standard locking screws while retaining the overall strength of the PFF fixations.

METHODS

Twelve laboratory models of Vancouver type B1 PFFs were developed. In all specimens, the proximal screw fixations were similar, whereas in 6 specimens, distal locking screws were used, and in the other six specimens, far cortical locking screws. The overall stiffness, fracture movement, and pattern of strain distribution on the plate were measured in stable and unstable fractures under anatomic 1-legged stance. Specimens with unstable fracture were loaded to failure.

RESULTS

No statistical difference was found between the stiffness and fracture movement of the two groups in stable fractures. In the unstable fractures, the overall stiffness and fracture movement of the locking group was significantly higher and lower than the far cortical group, respectively. Maximum principal strain on the plate was consistently lower in the far cortical group, and there was no significant difference between the failure loads of the 2 groups.

CONCLUSION

The results indicate that far cortical locking screws can reduce the overall effective stiffness of the locking plates and increase the fracture movement while maintaining the overall strength of the PFF fixation construct. However, in unstable fractures, alternative fixation methods, for example, long stem revision might be a better option.

Treatment for spondylolysis and spondylolisthesis in children

PURPOSE

To review outcome of 44 children who underwent conservative or surgical treatment for spondylolysis or spondylolisthesis.

METHODS

Records of 25 male and 19 female children aged 5 to 14 (mean, 10.2) years who underwent conservative (n=39) or surgical (n=5) treatment for spondylolysis (n=19) or spondylolisthesis (n=25) were reviewed. Conservative treatment involved application of a thoracolumbosacral orthotic brace for all day except bedtime until symptoms resolved and then physiotherapy including exercises to strengthen the abdominal and back muscles and stretching exercises of the hamstrings and hip flexors. Surgery (instrumented posterolateral fusion [n=4] or Wiltse posterolateral fusion [n=1]) with allografts was indicated in patients with refractory pain (n=2) or nerve root irritation (n=1) and in patients with iatrogenic spondylolisthesis (n=2), followed by application of the brace for 3 months and then physiotherapy. Outcome was assessed using the Seitsalo scoring system.

RESULTS

The mean follow-up period was 6.5 (range, 3-10) years. No patient developed any postoperative complication. Outcome was excellent in 35 patients, good in 8, and fair in one. All 5 patients who underwent posterolateral fusion for refractory spondylolisthesis achieved good outcome. In 11 patients with spondylolysis, the pars defect healed. None of the spondylolysis progressed to spondylolisthesis. All displacements remained stable, without any progression.

CONCLUSION

Conservative treatment is effective for most patients with spondylolysis or spondylolisthesis. Instrumented posterolateral fusion is indicated in patients with persistent symptoms and for iatrogenic cases.

Periprosthetic femoral fracture fixation: a biomechanical comparison between proximal locking screws and cables

BACKGROUND

The incidence of periprosthetic femoral fractures (PFF) around a stable stem is increasing. The aim of this biomechanical study was to examine how three different methods of fixation, for Vancouver type B1 PFF, alter the stiffness and strain of a construct under various configurations, in order to gain a better insight into the optimal fixation method.

METHODS

Three different combinations of proximal screws and Dall-Miles cables were used: (A) proximal unicortical locking screws alone; (B) proximal cables and unicortical locking screws; (C) proximal cable alone, each in combination with distal bicortical locking screws, to fix a stainless steel locking compression plate to five synthetic femora with simulated Vancouver type B1 PFFs. In one synthetic femora, there was a 10-mm fracture gap, in order to simulate a comminuted injury. The other four femora had no fracture gap, to simulate a stable injury. An axial load was applied to the constructs at varying degrees of adduction, and the overall construct stiffness and surface strain were measured.

RESULTS

With regards to stiffness, in both the gap and no gap models, method of fixation A was the stiffest form of fixation. The inclusion of the fracture gap reduced the stiffness of the construct quite considerably for all methods of fixation. The strain across both the femur and the plate was considerably less for method of fixation C, compared to A and B, at the locations considered in this study.

CONCLUSION

This study highlights that the inclusion of cables appears to damage the screw fixations and does not aid in construct stability. Furthermore, the degree of fracture reduction affects the whole construct stability and the bending behaviour of the fixation.

Management of glucocorticoid-induced osteoporosis: clinical data in relation to disease demographics, bone mineral density and fracture risk

INTRODUCTION

Glucocorticoid-induced osteoporosis (GIOP) is the most common type of secondary osteoporosis. Patient selection and the treatment choice remain to be controversial. None of the proposed management guidelines are widely accepted. We evaluate the available clinical data, the efficacy of current medication and we propose an overall algorithm for managing GIOP.

AREAS COVERED

This article provides a critical review of in vivo and clinical evidence regarding GIOP and developing evidence-based algorithm of treatment. Data base used includes MEDLINE® (1950 to May 2014).

EXPERT OPINION

Patient-specific treatment is the gold standard of care. Glucocorticoid (GC)-treated patients must comply with a healthy lifestyle and receive 1000 mg of calcium and at least 800 mg of Vitamin D daily. Bisphosphonate (BP) therapy is the current standard of care for prevention and treatment of GIOP. Most of bisphosphonates demonstrated benefit in lumbar bone mineral density (BMD) and some in hip BMD. Alendronate, risedronate and zoledronate showed vertebral anti-fracture efficacy in postmenopausal women and men. Scarce data however when compared head to head with BP efficacy. In post-menopausal women, early antiresorptive BP treatment appears to be efficient and safe. In premenopausal women and patients at high risk of fracture receiving long-term GC therapy however, teriparitide may be advised alternatively.

The biomechanical effect of bone quality and fracture topography on locking plate fixation in periprosthetic femoral fractures

Optimal management of periprosthetic femoral fractures (PFF) around a well fixed prosthesis (Vancouver B1) remains controversial as adequate fixation needs to be achieved without compromising the stability of the prosthesis. The aim of this study was to highlight the effect of bone quality i.e. canal thickness ratio (CTR), and fracture topography i.e. fracture angle and its position in relation to the stem, on the biomechanics of a locking plate for a Vancouver B1 fracture. A previously corroborated simplified finite element model of a femur with a cemented total hip replacement stem was used in this study. Canal thickness ratio (CTR) and fracture topography were altered in several models and the effect of these variations on the von Mises stress on the locking plate as well as the fracture displacement was studied. Increasing the CTR led to reduction of the von Mises stress on the locking plate as well as the fracture movement. In respect to the fracture angle with the medial cortex, it was shown that acute angles resulted in lower von Mises stress on the plate as opposed to obtuse angles. Furthermore, acute fracture angles resulted in lower fracture displacement compared to the other fractures considered here. Fractures around the tip of the stem had the same biomechanical effect on the locking plate. However, fractures more distal to the stem led to subsequent increase of stress, strain, and fracture displacement. Results highlight that in good bone quality and acute fracture angles, single locking plate fixation is perhaps an appropriate management method. On the contrary, for poor bone quality and obtuse fracture angles alternative management methods might be required as the fixation might be under higher risk of failure. Clinical studies for the management of PFF are required to further support our findings.

The effect of the timing of antibiotics and surgical treatment on infection rates in open long-bone fractures: a 6-year prospective study after a change in policy

Our current protocol in treating open long-bone fractures includes early administration of intravenous antibiotics and surgery on a scheduled trauma list. This represents a change from a previous protocol where treatment as soon as possible after injury was carried out. This review reports the infection rates in the period 6 years after the start of this protocol. Two hundred and twenty open long-bone fractures were reviewed. Data collected included time of administration of antibiotics, time to theatre and seniority of surgeon involved. The patients were followed up until clinical or radiological union occurred or until a secondary procedure for non-union or infection was performed. Clinical, radiological and haematological signs of infection were documented. If present, infection was classified as deep or superficial. Surgical debridement was performed within 6 h of injury in 45 % of cases and after 6 h in 55 % of cases. Overall infection rates were 11 and 15.7 %, respectively (p = 0.49). The overall deep infection rate was 4.3 %. There was also no statistically significant difference in the subgroups of deep (p = 0.46) and superficial (p = 0.78) infection. Intravenous antibiotics were administered within 3 h of injury in 80 % of cases and after 3 h in 20 % of cases. The infection rates were 14 and 12.5 %, respectively (p = 1.0). There was no statistically significant difference in the subgroups of deep (p = 0.62) and superficial (p = 0.73) infection. Further statistical analysis did not reveal a significant difference in infection rates for any combination of timing of antibiotics and surgical debridement. Infection rates where the most senior surgeon present was a consultant were 9.5 % as opposed to 16 % with the consultant not present, but this trend was not statistically significant. These results suggest that the change in policy may have contributed to an improvement of the deep infection rate to 4.3 % from the previous figure of 8.5 % although this decrease is not statistically significant. Surgeons may have had concerns that delaying theatre may lead to an increased infection rate, but these results do not substantiate this concern.

Open reduction internal fixation of lateral humeral condyle fractures in children. A series of 105 fractures from a single institution

Lateral humeral condyle fractures account for 17 % of the distal humeral condyle fractures. Displaced and/or rotated fractures require appropriate reduction and stabilisation. There are, however, a number of controversies in the surgical management of these patients. The aim of the present study was to review the results of patients with a displaced lateral humeral condyle fracture treated with open reduction and internal fixation (ORIF). We retrospectively reviewed children treated with ORIF of lateral humeral condyle fractures at a single institution over a period of 13 years. All cases were identified through the trauma register. Case notes and radiographs were retrieved. Fracture classification, mode of fixation, time to union, and final outcomes at the latest follow-up were reviewed. One hundred and five lateral condyle fractures were identified in 76 male and 29 female patients. Average age was 6.2 years. Ninety-two were Milch type II and 13 Milch type I. According to the Jacob’s classification, 38 were type II and 67 type III. All fractures were treated with open reduction and fixation with K-wires. Average time to radiological union was 33 days. Follow-up ranged between 2 and 8 years (average 3.2 years). Radiological hypertrophy of the lateral condyle was present in 45 cases (42 %). Three patients developed a pseudo-cubitus varus deformity. Further four patients developed a true cubitus varus. There was one case of superficial infection of the K-wires and one case of delayed union. At the latest follow-up, 96 % of the patients achieved an excellent final result and 4 % a good final result. Our results demonstrate that fracture union and excellent final outcomes can be expected in all patients using our protocol, whereby all patients with a displaced fracture are managed by ORIF with K-wire fixation, with the wires only being removed after there is evidence of radiological union. Compared to recent reports of closed reduction internal fixation, this series demonstrates good results with no complications directly relating to the open reduction technique. Level of evidence Case series, Level IV.

A preliminary study of manipulation under anaesthesia for secondary frozen shoulder following breast cancer treatment

INTRODUCTION

The aim of this paper is to present the results of manipulation under anaesthesia (MUA) and injection of local anaesthetic and corticosteroid followed by a physiotherapy regime for secondary frozen shoulder after breast cancer treatment (surgery, radiotherapy), and to compare them with a control group.

METHODS

Patients referred to the senior author for secondary frozen shoulder following breast cancer treatment over a ten-year period were investigated. Recorded data included age, treatment for breast cancer, length of symptoms, Oxford shoulder score (OSS) and range of motion before and after shoulder MUA. These data were compared with a control group of patients with frozen shoulder.

RESULTS

A total of 263 patients were referred with 281 frozen shoulders. Of these, 7 patients (7 shoulders) had undergone previous breast cancer treatment and the remaining 256 patients (274 shoulders) formed the control group. None of the patients were diabetic. The mean preoperative OSS was 31 for the study group and 27 for the control group, improving to 43 for both groups following MUA. Forty-two per cent of the study group and fifteen per cent of the control group had a second MUA subsequently. At the long-term follow-up appointment, 71% of the study group patients were satisfied with their result.

CONCLUSIONS

The results of this preliminary study suggest that MUA, corticosteroid injection and subsequent physiotherapy have achieved good final results in a series of patients with frozen shoulder secondary to breast cancer treatment. Members of the multidisciplinary team looking after breast cancer patients should be aware of this management option and, on manifestation of this pathology, should refer the patient to an orthopaedic surgeon.

Admission inflammatory markers and isolation of a causative organism in patients with spontaneous spinal infection

INTRODUCTION

The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.

METHODS

Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.

RESULTS

The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).

CONCLUSIONS

In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy.

Abstract S4-02: Integrated genomic analyses of members of protein kinase C family identifies subtype specific alterations as novel therapeutic targets

Introduction

Members of the protein kinase C family are serine/threonine kinases that are involved in proliferation, apoptosis, cell survival and migration, and have been implicated in tumorigenesis. Recently PRKCE has been found to be up-regulated in triple-negative (TN) breast cancers and has been proposed as a target for therapeutic intervention. The aims of this study were to determine i) whether different members of the PKC family are dysregulated and/ or mutated in specific subtypes of breast cancer, ii) to investigate the impact of silencing or overexpression of members of the PKC family in cell line models representative of the different breast cancer subtypes.

Material and methods:

We obtained expression and mutational data from the cancer genome atlas (TCGA) project from 567 and 640 samples subjected to microarray-based gene expression profiling and whole exome sequencing, respectively. Pair-wise SAM analysis of TCGA gene expression data was performed to identify differential expression between subgroups (ER+, HER2+ and TN). Potential driver mutations were identified through the algorithm CHASM. Subtype specific dependencies were identified from the re-analysis of publicly available siRNA kinome-wide screens in a panel of 20 breast cancer cell lines. In vitro assessment of gene overexpression was assessed in MCF10A cells by wound healing scratch assays and 3D growth in Matrigel.

Results

PRKCA, B, I and Q were expressed at significantly higher levels in TN breast cancers. Higher expression of PRKCE was significantly associated with ER-negativity, whereas high PRKCD expression was associated with ER-positivity. Analysis of siRNA kinome-wide screen data resulted in a significant reduction in survival associated with PRKCI and PRKCE in ER-negative cells, PRKCQ in triple-negative cells, and PRKCD in ER-positive cells. Furthermore meta-analysis of published exome and whole genome sequencing data identified potentially activating recurrent kinase domain mutations in PRKCB (0.93%), Q (1.25%) and Z (0.93%), with mutations in PRKCZ being associated with higher gene expression. Forced expression of wild-type PRKCQ and PRKCZ in MCF10A cells resulted in the formation of irregular acini in 3D cell culture and expression of wild-type PRKCZ resulted in increased migration.

Conclusions

Differential expression of members of the protein kinase C family, are associated with different molecular subtypes of breast cancer. Furthermore, we have shown that breast cancer cells are dependent upon expression of these family members in vitro, which are associated with different cellular phenotypes.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S4-02.

Evaluation of fracture topography and bone quality in periprosthetic femoral fractures: A preliminary radiographic study of consecutive clinical data

The unique configuration of periprosthetic femoral fractures (PFFs) is a major determinant of the subsequent management. The aim of this preliminary study was to investigate potential relationships between fracture angle (FA), fracture level (FL) and bone quality of Vancouver type B PFF. The FA, FL and the canal thickness ratio (CTR) were quantified for 27 patient X-rays. The CTR is an indicator of the underlying bone quality. Relationships between these factors were studied for the whole X-ray set, for a subgroup involving fracture above the tip of the stem and for subgroups with stable and unstable implants. When considering all cases, no significant correlation was found between the FA and any other measurement. Considering only cases with unstable implants, a statistically significant correlation was found between the FA and the FL (R(2)=0.489, p=0.002). No correlation was found between FA and any other measurement for stable implants suggesting that FA could be considered as an independent factor when classifying B1 fractures. Considering all cases, a weak correlation was found between CTR and FL (R(2)=0.152, p=0.044) suggesting that fractures below the tip of the stem may indicate a lower bone quality. This preliminary study suggests that the effect of FA on the optimal management of Vancouver type B1 fractures could be considered, independent of the quality of the bone or fracture position. Furthermore, fractures around or below the tip of the stem may suggest a poor bone quality. Larger number of patients is required to confirm these initial findings.

Admission inflammatory markers and isolation of a causative organism in patients with spontaneous spinal infection

INTRODUCTION

The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.

METHODS

Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.

RESULTS

The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).

CONCLUSIONS

In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy.

Comparison of different warfarin reversal protocols on surgical delay and complication rate in hip fracture patients

PURPOSE. To compare the effects of different warfarin reversal protocols on surgical delay and complication rate in hip fracture patients. METHODS. Records of 7 men and 17 women aged 68 to 93 (mean, 82) years who were on warfarin and underwent surgery for femoral neck fractures were reviewed. The time to surgery, complication rate, and mortality were recorded, as were the International Normalised Ratio (INR) on admission and the day of operation, as well as the dose, route, and time of administration of vitamin K for reversing the anticoagulation effect of warfarin. Patients were divided into 4 groups based on the warfarin reversal treatment. Group 1 (n=4) included patients who did not receive reversal treatment, as their admission INR was 1.5 or less. Group 2 (n=6) included patients who did not receive reversal treatment even though their INR was >1.6. Group 3 (n=5) included patients who received inappropriate reversal treatment (late or low-dose oral administration). Group 4 (n=9) included patients who received appropriate reversal treatment in terms of dose, route, and time of administration. RESULTS. Among the 4 groups, the mean INR was 2.2 (range, 1.3-4.6) on admission and 1.4 (range, 1.0-1.6) on the day of surgery. Group 1 was excluded from further analysis. Respectively in groups 2, 3, and 4, the mean times to surgery were 2.3, 2.6, and 1.2 days, and the complication rates were 67%, 20%, and 11%. CONCLUSION. Early administration of intravenous vitamin K for hip fracture patients on warfarin is recommended to ensure early operative management and avoid postoperative complications.

Locking plate fixation for Vancouver B1 periprosthetic femoral fractures: a critical analysis of 135 cases

PURPOSE

The overall incidence of periprosthetic femoral fractures (PPF) is between 0.1 and 6 % of all total hip arthroplasties. Locking compression plates (LCP) have been used for the treatment of Vancouver B1 PPFs with variable results. The aim of this study is to examine the literature on locking plate failure rates, mode and reasons for failure.

METHODOLOGY

A literature search was conducted for studies reporting the management of PPF of the femur with LCP fixation. The primary medical search engines used for the study were Ovid MEDLINE and EMBASE databases up to August 2012.

RESULTS

Twelve studies were identified, reporting overall union rates of 91 % in 135 fractures. Only 7 (5 %) fractures required revision surgery due to plate fracture (5) or pull out (2). Important trends in plate complications included: stress riser at the end of the plate, stress concentration in the fracture area due to rigid fixation, early loading and absence of cortical strut grafting for biological support when needed.

CONCLUSION

LCP has been used successfully in the management of Vancouver B1 PPF. However, potential areas of improvement include, leaving the fracture site free of locking screws, therefore, not disturbing the soft tissue envelope around the fracture and also reducing plate stiffness. Adding cortical strut allografts to improve stability and bone quality, if needed, may also improve outcome. Limitations in the use of strut grafts or transverse fractures below the tip of the stem that cannot be controlled with single or double plating may require long stem revision to achieve axial stability.

Disease-modifying osteoarthritis drugs: in vitro and in vivo data on the development of DMOADs under investigation

INTRODUCTION

Osteoarthritis is a disabling affliction, and disease-modifying osteoarthritis drugs (DMOADs) would be highly desirable adjuncts to symptomatic relief as they may delay the disease process.

AREAS COVERED

This study is a comprehensive review of the recent literature on the efficacy of DMOADs in the treatment of OA. In vitro and in vivo evidence was collected using MEDLINE® (1950 to November 2012) and EMBASE (1980 to November 2012) databases. Several drugs have demonstrated DMOAD effects in OA. They can be divided into three groups based on their predominant mode of action: those targeting cartilage, inflammatory pathways and subchondral bone. OARSI guidelines recommend glucosamine and chondroitin sulphates and diacerein as DMOADS, and NICE will recommend glucosamine sulphate in the next update of guidelines. Exploration of improved outcome measures and identification of subgroups of patients most likely to benefit from different DMOADs are likely to be the most important areas of development over the coming years.

EXPERT OPINION

It is expected that a wider range of prospective clinical studies will be embarked upon in the coming years. Trials including MRI as well as joint space narrowing (JSN) should be designed in a systematic manner, powered with sufficient numbers to demonstrate clinical benefit at different stages of disease.

Bone metabolism in anorexia nervosa: molecular pathways and current treatment modalities

Eating disorders are associated with a multitude of metabolic abnormalities which are known to adversely affect bone metabolism and structure. We aimed to comprehensively review the literature on the effects of eating disorders, particularly anorexia nervosa (AN), on bone metabolism, bone mineral density (BMD), and fracture incidence. Furthermore, we aimed to highlight the risk factors and potential management strategies for patients with eating disorders and low BMD. We searched the MEDLINE/OVID (1950-July 2011) and EMBASE (1980-July 2011) databases, focussing on in vitro and in vivo studies of the effects of eating disorders on bone metabolism, bone mineral density, and fracture incidence. Low levels of estrogen, testosterone, dehydroepiandrosterone, insulin-like growth factor-1 (IGF-1), and leptin, and high levels of cortisol, ghrelin, and peptide YY (PYY) are thought to contribute to the 'uncoupling' of bone turnover in patients with active AN, leading to increased bone resorption in comparison to bone formation. Over time, this results in a high prevalence and profound degree of site-specific BMD loss in women with AN, thereby increasing fracture risk. Weight recovery and increasing BMI positively correlate with levels of IGF-1 and leptin, normalisation in the levels of cortisol, as well as markers of bone formation and resorption in both adolescent and adult patients with AN. The only treatments which have shown promise in reversing the BMD loss associated with AN include: physiologic dose transdermal and oral estrogen, recombinant human IGF-1 alone or in combination with the oral contraceptive pill, and bisphosphonate therapy.

Cement-in-cement acetabular revision with a constrained tripolar component

Dislocation of a total hip replacement (THR) is common following total hip arthroplasty (THA). When nonoperative management fails to maintain reduction, revision surgery is considered. The use of constrained acetabular liners has been extensively described. Complete removal of the old cement mantle during revision THA can be challenging and is associated with significant complications. Cement-in-cement revision is an established technique. However, the available clinical and experimental studies focus on femoral stem revision. The purpose of this study was to present a case of cement-in-cement acetabular revision with a constrained component for recurrent dislocations and to investigate the current best evidence for this technique. This article describes the case of a 74-year-old woman who underwent revision of a Charnley THR for recurrent low-energy dislocations. A tripolar constrained acetabular component was cemented over the primary cement mantle following removal of the original liner by reaming, roughening the surface, and thoroughly irrigating and drying the primary cement. Clinical and radiological results were good, with the Oxford Hip Score improving from 11 preoperatively to 24 at 6 months postoperatively. The good short-term results of this case and the current clinical and biomechanical data encourage the use of the cement-in-cement technique for acetabular revision. Careful irrigation, drying, and roughening of the primary surface are necessary.

Patellar resurfacing in total knee arthroplasty: does design matter? A meta-analysis of 7075 cases

BACKGROUND

Patellar resurfacing in total knee arthroplasty remains controversial. The aim of this study was to compare outcomes following total knee arthroplasty with patellar resurfacing with those following total knee arthroplasty without patellar resurfacing. We also sought to identify any correlation between outcomes and prosthetic design.

METHODS

Eighteen Level-I randomized controlled trials with a cumulative sample size of 7075 knees (3463 in the resurfacing group and 3612 in the non-resurfacing group) satisfied the inclusion criteria. In the primary analysis, patellar resurfacing total knee arthroplasty was compared with non-resurfacing total knee arthroplasty, with use of reoperation rates, incidence of anterior knee pain, and functional scores as outcome measures. The secondary analysis focused on comparing patella-friendly and non-patella-friendly total knee arthroplasty designs with regard to the same three outcome measures.

RESULTS

No significant differences were found between the resurfacing and non-resurfacing groups with regard to the incidence of anterior knee pain. A higher rate of reoperations was observed in the non-resurfacing group. Analysis of homogeneous data comparing patella-friendly with non-patella-friendly total knee arthroplasty designs demonstrated no differences in the incidence of reoperations.

CONCLUSIONS

No evidence was found to suggest that either patellar resurfacing or the prosthetic design affects the clinical outcome of a total knee arthroplasty. The higher incidence of reoperations in the non-resurfacing group may be attributed to the fact that secondary patellar resurfacing adds a surgical option for the treatment of anterior knee pain following total knee arthroplasty, thus artificially increasing the rate of reoperations in the non-resurfacing group.

Biological therapy of bone defects: the immunology of bone allo-transplantation

IMPORTANCE OF THE FIELD

Bone is one of the most transplanted tissues worldwide. Autograft is the ideal bone graft but is not widely used because of donor site morbidity and restricted availability. Allograft is easily accessible but can transmit infections and elicit an immune response.

AREAS COVERED IN THIS REVIEW

This review identifies all in vitro and in vivo evidence of immune responses following bone transplantation and highlights methods of improving host tolerance to bone allotransplantation.

WHAT THE READER WILL GAIN

In humans, the presence of anti-HLA specific antibodies against freeze-dried and fresh-frozen bone allografts has been demonstrated. Fresh-frozen bone allograft can still generate immune reactions whilst freeze-dried bone allografts present with less immunogenicity but have less structural integrity. This immune response can have an adverse effect on the graft's incorporation and increase the incidence of rejection. Decreasing the immune reaction against the allograft by lowering the immunogenic load of the graft or lowering the host immune response, would result in improved bone incorporation.

TAKE HOME MESSAGE

It is essential that the complex biological processes related to bone immunogenicity are understood, since this may allow the development of safer and more successful ways of controlling the outcome of bone allografting.