Aim. Shelf acetabuloplasty is part of the armamentarium for the treatment of Legg-Perthes-Calve disease. Surgeons have used it to increase the anterolateral cover of the deformed head in advanced stages of the disease. However, others, including the senior author, advocate its use for containment of the diseased femoral head earlier in the disease, for both the prevention of further femoral head extrusion and as an aid in the remodelling process. The current study presents the results of this procedure performed from August 1999 to February 2010. Method. Full sets of x-rays were available for 44 patients (45 hips). Three other bilateral cases were treated with a unilateral shelf. Results. This series includes 34 boys and 10 girls with a mean age at diagnosis of 7.5 years (range 3.9 to 15.3). The average time to heal was 37.6 months (range 12–62.4). Over 80% of the hips were Elizabethtown stages 1 and 2 and almost 70% were Herring B at the time of surgery. However, 66% presented with more than two head-at-risk signs. Reimer's migration index and the deformity index were measured on initial, preoperative, postoperative and healed x-rays. The average deformity index at those four time points was significantly related to their final Stulberg classification. CE angles increased and Sharp angles decreased significantly as a result of treatment. Although many shelf grafts showed progressive resorption, the overall acetabular depth increased. At the healed stage, 82.2% of patients were Stulberg 3 or less, denying any pain and with full range of movement whilst 17.8% were classified as Stulberg 4. One of them required a Sugioka valgus osteotomy due to continuous pain. Conclusion. Shelf acetabuloplasty should be considered not only a salvage procedure but also indicated for the containment of extruded hips in earlier stages of Perthes disease

The safety of nucleus implants remains an open issue in the treatment of intervertebral disc degeneration. Post-operative migration and subsequent extrusion represent a high risk of potential unsatisfactory outcome. The effectiveness of additionally sewing a biointegrative nucleus implant into an annulus defect was investigated therefore in this experiment. Laminectomy preserving the facet joints was performed on seven human functional spinal units (FSU’s). A reproducible annulus defect of 6×6 mm was incised, followed by a standard nucleotomy procedure and subsequent introduction of the implants. These woven patches consist of biointegrative, absorbable polyglycolic acid (PGA), lyophilized with hyaluronic acid. The annulus sealing technique requires placing a PGA-patch adjacent to the inner annulus, fixed by sutures (Polysorb 3-0, Syneture) at its four corners. Unsealed annulus defects served as a control group. FSU’s were loaded with a bending torque of 5 to 7.5 Nm. Continual revolution of the specimen around its vertical axis resulted in a combination of lateral, dorsal and flexural bending. During application of loads, implant herniation level was determined every 1 000 cycles according to predefined criteria. Tests were stopped after reaching 20 000 cycles. Five of totally six sewed specimens withstood 20 000 load cycles, whereas only one of five not sewed specimens terminated successfully. Based on the Mann-Whitney test, significant increase in stability can be detected for the sewed procedure. Sewing a biointegrative annulus implant into an annulus defect improves nucleus implant containment. It remains to be shown whether this annulus sealing technique is also effective in highly degenerated annulus tissue. Furthermore, a minimally invasive implantation device is crucial for application in a clinical setting

Purpose: Many strategies have been reported for decreasing the cost of orthopaedic procedures, including negotiating lower prices with manufacturers and using lower-cost generic implants, but prosthetic waste has not been investigated. The purpose of this study was to characterize the present and potential future cost of intra-operative waste of hip and knee implants. Method: A regional prospective assessment of implant waste was performed from January 2007 to June 2008, evaluating the incidence and reasons for component waste, the cost of the wasted implants, and where the cost was absorbed (hospital or manufacturer). Using published data on nationwide arthroplasty volumes, the results were extrapolated to the whole of the United States. Finally, based on peer-reviewed estimates of nationwide arthroplasty volumes for the next 20 years, a projection was made about the future cost burden of implant waste. Results: Implant waste occurred in 79 of 3443 recorded procedures (2%), with the surgeon bearing primary responsibility in 73% of occurrences. The annualized waste cost was $109,295.35, with 67% absorbed by the hospital. When extrapolated to the whole of the United States, the annual cost to hospitals of hip and knee prosthetic waste is $36,019,000, and is estimated to rise to $112,033,000 in current dollars by the year 2030. Conclusion: This study discovered a notable incidence of intra-operative hip and knee implant waste, with the majority of cases attributed to the surgeon, and representing an important additional cost burden on hospitals. With arthroplasty rates projected to increase markedly over the next twenty years, this waste represents a potentially noteworthy target for educational programs and other cost containment measures in orthopaedic surgery

Aims. The aim of this study was to evaluate the epidemiology and treatment of Perthes’ disease of the hip. Methods. This was an anonymized comprehensive cohort study of Perthes’ disease, with a nested consented cohort. A total of 143 of 144 hospitals treating children’s hip disease in the UK participated over an 18-month period. Cases were cross-checked using a secondary independent reporting network of trainee surgeons to minimize those missing. Clinician-reported outcomes were collected until two years. Patient-reported outcome measures (PROMs) were collected for a subset of participants. Results. Overall, 371 children (396 hips) were newly affected by Perthes’ disease arising from 63 hospitals, with a median of two patients (interquartile range 1.0 to 5.5) per hospital. The annual incidence was 2.48 patients (95% confidence interval (CI) 2.20 to 2.76) per 100,000 zero- to 14-year-olds. Of these, 117 hips (36.4%) were treated surgically. There was considerable variation in the treatment strategy, and an optimized decision tree identified joint stiffness and age above eight years as the key determinants for containment surgery. A total of 348 hips (88.5%) had outcomes to two years, of which 227 were in the late reossification stage for which a hip shape outcome (Stulberg grade) was assigned. The independent predictors of a poorer radiological outcome were female sex (odds ratio (OR) 2.27 (95% CI 1.19 to 4.35)), age above six years (OR 2.62 (95% CI (1.30 to 5.28)), and over 50% radiological collapse at inclusion (OR 2.19 (95% CI 0.99 to 4.83)). Surgery had no effect on radiological outcomes (OR 1.03 (95% CI 0.55 to 1.96)). PROMs indicated the marked effect of the disease on the child, which persisted at two years. Conclusion. Despite the frequency of containment surgery, we found no evidence of improved outcomes. There appears to be a sufficient case volume and community equipoise among surgeons to embark on a randomized clinical trial to definitively investigate the effectiveness of containment surgery. Cite this article: Bone Joint J 2022;104-B(4):510–518

In the current healthcare environment, cost containment has become more important than ever. Perioperative services are often scrutinized as they consume more than 30% of North American hospitals’ budgets. The procurement, processing, and use of sterile surgical inventory is a major component of the perioperative care budget and has been recognized as an area of operational inefficiency. Although a recent systematic review supported the optimization of surgical inventory reprocessing as a means to increase efficiency and eliminate waste, there is a paucity of data on how to actually implement this change. A well-studied and established approach to implementing organizational change is Kotter's Change Model (KCM). The KCM process posits that organizational change can be facilitated by a dynamic 8-step approach and has been increasingly applied to the healthcare setting to facilitate the implementation of quality improvement (QI) interventions. We performed an inventory optimization (IO) to improve inventory and instrument reprocessing efficiency for the purpose of cost containment using the KCM framework. The purpose of this quality improvement (QI) project was to implement the IO using KCM, overcome organizational barriers to change, and measure key outcome metrics related to surgical inventory and corresponding clinician satisfaction. We hypothesized that the KCM would be an effective method of implementing the IO. This study was conducted at a tertiary academic hospital across the four highest-volume surgical services - Orthopedics, Otolaryngology, General Surgery, and Gynecology. The IO was implemented using the steps outlined by KCM (Figure 1): 1) create coalition, 2) create vision for change, 3) establish urgency, 4) communicate the vision, 5) empower broad based action, 6) generate general short term wins, 7) consolidate gains, and 8) anchor change. This process was evaluated using inventory metrics - total inventory reduction and depreciation cost savings; operational efficiency metrics - reprocessing labor efficiency and case cancellation rate; and clinician satisfaction. The implementation of KCM is described in Table 1. Total inventory was reduced by 37.7% with an average tray size reduction of 18.0%. This led to a total reprocessing time savings of 1333 hours per annum and labour cost savings of $39 995 per annum. Depreciation cost savings was $64 320 per annum. Case cancellation rate due to instrument-related errors decreased from 3.9% to 0.2%. The proportion of staff completely satisfied with the inventory was 1.7% pre-IO and 80% post-IO. This was the first study to show the success of applying KCM to facilitate change in the perioperative setting with respect to surgical inventory. We have outlined the important organizational obstacles faced when making changes to surgical inventory. The same KCM protocol can be followed for optimization processes for disposable versus reusable surgical device purchasing or perioperative scheduling. Although increasing efforts are being dedicated to quality improvement and efficiency, institutions will need an organized and systematic approach such as the KCM to successfully enact changes. For any figures or tables, please contact the authors directly

Escalating health care expenditure worldwide is driving the need for effective resource decision-making, with medical practitioners increasingly making complex resource decisions within the context of patient care. Despite raising serious legal and ethical issues in practice, this has attracted little attention in Australia, or internationally. In particular, it is unknown how orthopaedic surgeons perceive their obligations to the individual patient, and the wider community, when rationing care, and how they reconcile competing obligations. This research explores legal and ethical considerations, and resource allocation by Australian orthopaedic surgeons, as a means of achieving public health cost containment driven by macro-level policy and funding decisions. This research found that Australian orthopaedic surgeon's perceptions, and resource allocation decision making, can be explained by understanding how principles of distributive justice challenge, and shift, the traditional medical paradigm. It found that distributive justice, and challenges of macro level health policy and funding decisions, have given rise to two new medical paradigms. Each which try to balance the best interests of individual patients with demands in respect of the sustainability of the health system, in a situation where resources may be constrained. This research shows that while bedside rationing has positioned the medical profession as the gate keepers of resources, it may have left them straddling an increasingly irreconcilable void between the interests of the individual patient and the wider community, with the sustainability of the health system hanging in the balance

Opinions about the treatment of Perthes' disease vary widely. However there is no disagreement about the need for containment during fragmentation stage to create an optimum biomechanical environment for remodelling of femoral head. Types of containment may vary. Younger children do well irrespective of the method of containment. Older children usually require surgical containment. The present study was aimed at evaluating the results of different methods of surgical containment in different age group and identifying specific factors that alter the final outcome and prognosis. 107 cases were reviewed retrospectively. 21 cases were excluded due to lack of records. 86 hips were available for clinical and radiological evaluation. 31 patients were under 7 years and required Varus osteotomy (VO). 55 patients were above 7 years. VO was performed in 30 hips and Shelf containment was done in 25. Case notes were reviewed for demographic details, surgical details and clinic letters. Radiographs were reviewed for Herring's grading, Stulberg staging, containment indices, centre edge angle, lateral pillar height, Mose index, neck shaft angle and shelf width. In all patients, there was an improvement in pre-operative symptoms and summated range of motion, especially abduction. Good functional and radiological outcome was seen in age group < 7 years. In older children, outcome was good to satisfactory with Herring grade B. Stulberg grading worsened with advancing age and Herring grade C, irrespective of the method of containment. Persistence of varus neck shaft angle and trochanteric overgrowth were significant problems with VO. Although all containment indices improved with Shelf group, Stulberg grading remained poor in most patients. The lateral pillar classification and age strongly correlate with final outcome. Herring group C had the least favourable result. Stulberg staging remained poor in older children irrespective of the method of containment

Aim. It still remains unclear whether postoperative antibiotic treatment is advantageous in presumed aseptic revision-arthroplasties of the hip (rTHA) and knee (rTKA) with unexpected-positive-intraoperative-cultures (UPIC). The aim of this study was to evaluate if there is a difference in the septic and/or aseptic re-revision rate in patients with or without postoperative antibiotics. Method. In this retrospective propensity-score (PS) matched cohort-study we compared the re-revision rate and the microbiological spectrum in rTHA and rTKA treated with (AB-Group; n=70) and without (non-AB-Group; n=70) antibiotic treatment in patients with UPIC. Baseline covariates for PS-matching were type of revision, sex, Body-Mass-Index, age, Surgical-Site-Infection-Score, American-Society-of-Anesthesiologists-Classification, serum C-reactive-protein. All patients received routine antibiotic prophylaxis, but empiric AB treatment was started only in patients in the AB-Group. Post-operative treatment was decided on an individual basis according to the preference of the surgeon and the infectious disease specialist for a minimum duration of two weeks. In total, 90 rTHA (45 AB-Group, 45 in non-AB-Group) patients with UPICs and 50 rTKA (25 AB-Group, 25 in non-AB-Group) were included in the study. There was no significant variation in patient demographics. Results. After a median follow-up of 4.1 (IQR: 2.9-5.5) years after rTHA and rTKA, there was no higher re-revision rate (p=0.813) between the AB-group 10/70 (14.3%), and the non-AB-group 11/70 (15.7%). In the AB group, 4.3% (3/70) of patients underwent revision due to septic complications compared to 5.7% (4/70) in the non-AB group (survival log-rank: p=0.691). In total, 30/70 (42.9%) of patients in the AB-group and 23/70 (32.9%) of patients in the non-AB group were diagnosed as having an “infection likely” according to the PJI diagnostic criteria of EBJIS (p=0.223). All UPICs comprised low virulent microorganisms and were considered as a contaminant. In total, 68/70 (97.1%) of the patients in the AB-group received a dual antibiotic treatment for a mean duration of 41 (IQR: 23.5-56.5) days. Conclusion. Postoperative antibiotic treatment did not result in a decreased re-revision rate compared to non-antibiotic treatment in patients with UPIC in presumed aseptic rTHA and rTKA. UPICs with pathogens are likely to be a containment and therefore the classification of “infection likely” according to the EBJIS definition can be safely ignored

Most cost containment efforts in public health systems have focused on regulating the use of hospital resources, especially operative time. As such, attempting to maximize the efficiency of limited operative time is important. Typically, hospital operating room (OR) scheduling of time is performed in two tiers: 1) master surgical scheduling (annual allocation of time between surgical services and surgeons) and 2) daily scheduling (a surgeon's selection of cases per operative day). Master surgical scheduling is based on a hospital's annual case mix and depends on the annual throughput rate per case type. This throughput rate depends on the efficiency of surgeons’ daily scheduling. However, daily scheduling is predominantly performed manually, which requires that the human planner simultaneously reasons about unknowns such as case-specific length-of-surgery and variability while attempting to maximize throughput. This often leads to OR overtime and likely sub-optimal throughput rate. In contrast, scheduling using mathematical and optimization methods can produce maximum systems efficiency, and is extensively used in the business world. As such, the purpose of our study was to compare the efficiency of 1) manual and 2) optimized OR scheduling at an academic-affiliated community hospital representative of most North American centres. Historic OR data was collected over a four year period for seven surgeons. The actual scheduling, surgical duration, overtime and number of OR days were extracted. This data was first configured to represent the historic manual scheduling process. Following this, the data was then used as the input to an integer linear programming model with the goal of determining the minimum number of OR days to complete the same number of cases while not exceeding the historic overtime values. Parameters included the use of a different quantile for each case type's surgical duration in order to ensure a schedule within five percent of the historic overtime value per OR day. All surgeons saw a median 10% (range: 9.2% to 18.3%) reduction in the number of OR days needed to complete their annual case-load compared to their historical scheduling practices. Meanwhile, the OR overtime varied by a maximum of 5%. The daily OR configurations differed from historic configurations in 87% of cases. In addition, the number of configurations per surgeon was reduced from an average of six to four. Our study demonstrates a significant increase in OR throughput rate (10%) with no change in operative time required. This has considerable implications in terms of cost reduction, surgical wait lists and surgeon satisfaction. A limitation of this study was that the potential gains are based on the efficiency of the pre-existing manual scheduling at our hospital. However, given the range of scenarios tested, number of surgeons included and the similarity of our hospital size and configuration to the majority of North American hospitals with an orthopedic service, these results are generalizable. Further optimization may be achieved by taking into account factors that could predict case duration such as surgeon experience, patients characteristics, and institutional attributes via machine learning

The coronavirus disease 2019 (COVID-19) pandemic has led to unprecedented challenges to healthcare systems worldwide. Orthopaedic departments have adopted business continuity models and guidelines for essential and non-essential surgeries to preserve hospital resources as well as protect patients and staff. These guidelines broadly encompass reduction of ambulatory care with a move towards telemedicine, redeployment of orthopaedic surgeons/residents to the frontline battle against COVID-19, continuation of education and research through web-based means, and cancellation of non-essential elective procedures. However, if containment of COVID-19 community spread is achieved, resumption of elective orthopaedic procedures and transition plans to return to normalcy must be considered for orthopaedic departments. The COVID-19 pandemic also presents a moral dilemma to the orthopaedic surgeon considering elective procedures. What is the best treatment for our patients and how does the fear of COVID-19 influence the risk-benefit discussion during a pandemic? Surgeons must deliberate the fine balance between elective surgery for a patient’s wellbeing versus risks to the operating team and utilization of precious hospital resources. Attrition of healthcare workers or Orthopaedic surgeons from restarting elective procedures prematurely or in an unsafe manner may render us ill-equipped to handle the second wave of infections. This highlights the need to develop effective screening protocols or preoperative COVID-19 testing before elective procedures in high-risk, elderly individuals with comorbidities. Alternatively, high-risk individuals should be postponed until the risk of nosocomial COVID-19 infection is minimal. In addition, given the higher mortality and perioperative morbidity of patients with COVID-19 undergoing surgery, the decision to operate must be carefully deliberated. As we ramp-up elective services and get “back to business” as orthopaedic surgeons, we have to be constantly mindful to proceed in a cautious and calibrated fashion, delivering the best care, while maintaining utmost vigilance to prevent the resurgence of COVID-19 during this critical transition period. Cite this article: Bone Joint Open 2020;1-6:222–228

Over the last several years, triple pelvic osteotomy has become our preferred method for surgical containment in Perthes disease. Since 1995, seventeen patients with Perthes disease have been treated with triple pelvic oste-otomy at our institution. Fourteen of seventeen patients (82%) had a good or excellent clinical result at latest follow-up. According to Sundt’s criteria, radiographic outcome was rated as good in fourteen patients (82%), fair in one patient and poor in two patients. Experience with the technical aspects of the procedure is necessary to avoid pseudarthrosis and iatrogenic external rotation of the acetabular fragment. To evaluate the efficacy of triple pelvic osteotomy as a method of surgical containment in Perthes disease. Recent trends point to surgery as the method of choice for containment in older children with Perthes disease. Over the last several years, triple pelvic osteotomy has become our preferred method for surgical containment in Perthes disease. Since 1995, seventeen patients (seventeen hips) with Perthes disease classified as either lateral pillar B or C have been treated with triple pelvic osteotomy at our institution. The average age at surgery was 8.5 years with an average follow-up of 4.3 years. Outcome was assessed using clinical as well as multiple radiographic criteria. Fourteen of seventeen patients (82%) had a good or excellent clinical result at latest follow-up. No patients had a residual limp or limb length inequality. Two patients had a minor postoperative complication (transient peroneal nerve palsy, meralgia paresthetica). According to Sundt’s criteria, radiographic outcome was rated as good in fourteen patients (82%), fair in one patient and poor in two patients. Triple pelvic osteotomy minimizes potential complications associated with other surgical methods such as Trendelenberg gait and shortening with proximal femoral osteotomy or hinge abduction following a Salter innominate osteotomy. Experience with the technical aspects of the procedure is necessary to avoid pseudarthrosis and iatrogenic external rotation of the acetabular fragment. Triple pelvic osteotomy is now our procedure of choice for containment in the older child with Perthes disease

Introduction: Autopsy findings (Jensen and Lauritzen 1976, Catterall et al. 1982) as well as own MRI studies (Lange et al. 1996) indicate that in Perthes’ disease there is an early cartilaginous enlargement of the femoral head. Lack of concomitant acetabular enlargement will lead to loss of containment and subluxation. We divided the transverse acetabular ligament (TAL) to promote expansion of the acetabulum for prevention of femoral head extrusion and loss of containment. Material and Methods: We report 13 patients with Perthes’disease belonging to Catterall group III or IV. The operation was performed when MRI showed a labrum lift near horizontal position indicating risk of loss of containment (Meiss 2001). There was an average cartilaginous head enlargement of 11 % in comparison to the uneffected side as measured by the Maximum Oblique Diameter. Division of the TAL was performed through an antero-medial approach (Ludloff 1913, Wein-stein 1993). A window of about 1,5 x 1 cm was created in the capsule which was left open. The TAL was divided but not removed. In all cases strict non-weightbearing was imposed postoperatively (use of a wheel chair and crutches) until well into the regeneration phase. The average period of non-weight-bearing was 1 year and 10 months. An abduction pillow was worn at night. Results: The results after an average follow-up of 4,2 years (range 2,6 -5,3 years) were evaluated according to Stulberg (1981) and Catterall (1982) with emphasis on the radiographic appearance (sphericity of the femoral head, joint congruity, containment [acetabulum head index], articulo-trochanteric distance). The result was excellent in 2 cases, good in 8, satisfactory in 2, and poor in 1 case. Two patients had a bad compliance for non-weightbearing and underwent additional bony procedures. The outcome was satisfactory and poor. Conclusions: Our data indicate that the combination of the division of the TAL and a strict conservative treatment gives very satisfactory results in Catterall group III and IV cases that present with signs of risk of loss of containment on MRI

The current ‘gold’ standard surgical intervention for critical size bone defect repair involves autologous bone grafting, that risks inadequate graft containment and soft tissue invasion. Here, a new regenerative strategy was explored, that uses a barrier membrane to contain bone graft. The membrane is designed to prevent soft tissue ingrowth, whilst supporting periosteal regrowth, an important component to bone regeneration. This study shows the development of a collagen-based barrier membrane supportive of periosteal-derived mesenchymal stem cell (P-MSC) growth. P-MSC-homing barrier membranes were successfully obtained with nonaligned fibres, via free-surface electrospinning using type I collagen and poly(E-caprolactone) in 1,1,1,3,3,3-Hexafluoro-2-propanol. Introduction of collagen in the electrospinning mixture was correlated with decreased mean fibre diameter (d: 319 nm) and pore size (p: 0.2–0.6 μm), with respect to collagen-free membrane controls (d: 372 nm; p: 1–2 μm). Consequently, as the average MSC diameter is 20 μm, this provides convincing evidence of the creation of a MSC containment membrane. SEM-EDX confirmed Nitrogen and therefore collagen fibre localisation. Quantification of collagen content, using Picro Sirius Red dye, showed a 50% reduction after 24 hours (PBS, 37 °C), followed by a drop to 25% at week 3. The collagen-based membrane has a significantly higher elastic modulus compared to collagen-free control membranes. P-MSCs attached and proliferated when grown onto collagen-based membranes, imaged using confocal microscopy over 3 weeks. A modified transwell cell migration assay was developed, using MINUSHEET® tissue carriers to assess barrier functionality. In line with the matrix architecture, the collagen-based membrane proved to prevent cell migration (via confocal microscopy) in comparison to the migration facilitating positive control. The aforementioned results obtained at molecular, cellular and macroscopic scales, highlight the applicability of this barrier membrane in a new ‘hybrid graft’ regenerative approach for the surgical treatment of critical size bone defects

We have documented the long term radiological outcome of developmental dysplasia of the hips (DDH) complicated by avascular necrosis (AVN). We have also assessed whether a policy of prolonged post-reduction containment has improved the results. Radiographs of patients with a minimum of 10 years followup wer assessed, and AVN diagnosed accordingly to Crerand and O’Brien’s criteria. Outcome grading was assessed by Severin’s criteria, and head sphericity using Mose’s rings. We identified 35 hips (35 patients) who had developed AVN. Twenty hips had a medial pattern of deformity, and 15 had a valgus pattern. Fifteen hips were Severin grade III, 13 were grade IV, and 3 were grade V. Twenty four patients had more than 6 mm discrepancy in the head of sphericity. Six patients were reviewed clinically: 4 of 5 patients who were < 24 years old have hip symptoms, and the other patient (age 41) has osteoarthritis. These results confirm that AVN is a serious complication with a poor longterm outcome, and that our prolonged containment treatment does not produce better results than those published on patients with shorter containment periods

Background: Femoral varus osteotomy for Perthes’ disease aims at achieving Containment to prevent femoral head deformation. Theoretically, ontainment is most likely to succeed if it is achieved before the femoral head extrudes and is subjected to deforming stresses. It would follow that the timing of the procedure is an important factor in determining the outcome. This study was undertaken to verify this. Methods: Records and radiographs of 610 patients with Perthes’ disease were analysed. The data of 302 patients who underwent femoral osteotomy were compared with those of non-operated patients. A new modification of the Elizabthtown classification of the stages of evolution of the disease with seven stages (Stages Ia, Ib, IIa, IIb, IIIa, IIIb & IV) was used to identify the timing of surgery and to monitor the progress of the disease following surgery. The results of treatment were assessed at healing by Mose’s criteria. Multivariate analysis was used to identify variables that influenced the shape and size of the femoral head at healing. Results: 22 patients among 86 who were operated in Stage Ia or Ib by-passed the stage of fragmentation. The extent of metaphyseal widening was considerably less in operated children. At healing, spherical femoral heads were seen in 72% of operated hips as compared to 24% of non-operated hips. The variables that influenced the shape of the femoral head at healing were, metaphyseal width, sex, age at onset, epiphyseal extrusion and the stage at surgery. Patients who were operated before Stage IIb had significantly better results than those operated later. Conclusions: The results of the study support the impression that the timing of containment is an important factor that influences the outcome in Perthes’ disease. The best results are obtained if containment is achieved before Stage IIb

Introduction: Therapeutic bone marrow transplantation has increased survival in Hurler syndrome, but the effects on musculoskeletal development remain unclear. Long term reports on mobility are poor, with many patients gradually losing walking ability in later childhood secondary to hip subluxation and joint contractures. As previous cohorts are small, data is limited. Methods: We detail the follow up of twenty patients over a mean of 94 months (range 1 – 17.4 years). Radiographs were assessed for hip dysplasia using acetabular angle of Sharp, centre edge angle of Wiberg and tibiofemoral shaft angle. Clinical examination was performed at an annual multidisciplinary assessment by one clinician and compared against age matched controls. 3D gait analysis was performed on eight older children, and deviance in kinematic variables was plotted against controls with Mann-Whitney U test for statistical analysis. Results: All patients demonstrated characteristic ace-tabular dysplasia. Fourteen patients have undergone containment surgery at a mean of 4.4 years. Innominate osteotomy is an essential part of this. Mean preoperative acetabular angle was reduced from 34 ± 4° to 22 ± 3°. Femoral head containment is maintained, with mean centre edge angle in older patients 39 ± 7°. Genu valgum is observed early, and five patients underwent medial epiphyseal stapling at a mean of 7.8 years, decreasing tibiofemoral angle by a mean of 8.0°. All patients are currently independently mobile, with restriction of internal hip rotation being the only significant clinical finding (P< 0.001). Joint contractures were not noted. Walking speed and stride length were comparable to controls, but endurance is reduced by about one quarter. Gait analysis demonstrates a characteristic pattern, with anterior pelvic tilt secondary to thoracolumbar gibbus, relative hip flexion throughout the gait cycle, valgus knees and compensatory pronated feet; all measured deviations were significant (P< 0.001). Conclusions This large group maintained successful hip containment and good mobility throughout childhood. Innominate osteotomy alone has been used recently. Despite plain film appearance, genu valgum is a functional problem in gait, and we would anticipate greater use of corrective stapling in the future. This is the first report of gait analysis in Hurler syndrome, and features specific to the condition are described

Femoral head deformity can be a devastating outcome in a small percentage of patients with Perthes' disease. Deformities usually start during the fragmentation stage. In this study, we aimed to determine the effects of Vitamin D deficiency on the natural history of Perthes' disease. Patients with Perthes' disease and Vitamin D deficiency presenting to our unit in the last 3 years were identified. All X-rays were reviewed retrospectively to determine the duration of the fragmentation and ossification stages. Treatment methods were obtained from the notes. Late presenters (i.e. after fragmentation stage) were excluded. In our unit, Vitamin D deficiency is diagnosed if levels <72 nmol/L. Fifteen patients (17 hips) with Perthes' disease were found to be Vitamin D deficient. Levels ranged from (18–71 nmol/L). The mean length of the fragmentation stage was 15.7 months which is significantly higher than quoted literature figures (8 months). Ossification stage duration was 18.8 months which was comparable to quoted figures. However, patients with severe Vitamin D deficiency (< 52 nmol/L) were found to have longer ossification stage (20.6 months) compared with patients with mild deficiency (52–72 nmol/L) (16.4 months). Seven out of 16 patients (44%) required surgical containment which is significantly higher than the usually low rates of surgical intervention. The critical fragmentation stage in Vitamin D deficiency is significantly longer putting the femoral head at higher risk of deformity and extrusion. This leads to higher rates of surgical containment. Also the severity of Vitamin D deficiency might be an important determinant of the period of time required for ossification and healing. Vitamin D level is an important prognostic factor and must be measured in all patients with Perthes' disease. Prescribing Vitamin D supplements is advisable in this group of patients. However, the effects of these supplements on the course of the disease requires further research. Level of evidence: III

Transposition osteotomy of the acetabulum (TOA) was the first periacetabular osteotomy for the osteoarthritis hips due to acetabular dysplasia, in which the acetabulum was transposed with articular cartilage. TOA improves coverage of the femoral head to restore congruity and stability, and also prevent further osteoarthritis deterioration and induce regeneration of the joint. Many good clinical outcomes have been reported for such periacetabular osteotomies for osteoarthritis of the hips at an early stage. In contrast, the clinical outcome is controversial for those hips at an advanced stage, in which the joint space has partly disappeared. The purpose of this study was to investigate whether TOA is an appropriate option for treatment of osteoarthritis of the hips at the advanced stage by comparing with matched control hips at the early stage. Between 1998 and 2001, TOA was performed in 104 hips of 98 patients. Sixteen of 17 hips (94%) with osteoarthritis at the advanced stage were examined and compared with 37 matched control hips at the early stage. The mean age at the operation was 48(38–56) and the mean follow-up period was 88 (65–107) months. TOA corrected the acetabular dysplasia and significantly improved containment of the femoral head. No hips had secondary operations including THA. Clinical scores were also significantly improved in both of the groups. In the advanced osteoarthritis cases, there was a tendency for abduction congruity before transposition osteotomy of the acetabulum to reflect the clinical outcome. TOA is a promising treatment option for the advanced osteoarthritis of the hips as well as for those patients at the early stage when preoperative radiographs show good congruity or containment of the joint

Introduction. Total shoulder replacement is a successful treatment for gleno-humeral osteoarthritis. However, components loosening and painful prostheses, related to components wrong positioning, are still a problem for those patients who underwent this kind of surgery. CT-based intraoperative navigation system is a suitable option to improve accuracy and precision of the implants as previously described in literature for others district. Method. Eleven reverse shoulder prostheses were performed at Modena Polyclinic from October 2018 to April 2019 using GPS CT-based intraoperative navigation system (Exactech, Gainsville, Florida). In the preoperative planning, Walch classification was used to assess glenoid type. The choice of inclination of the glenoid component, the screw length, as well as the inclination of the reamer was study and recorded using specific software using the CT scan of shoulder of each patient (Fig.1, Fig.2). Intraoperative and perioperative complications were recorded. Three patients were male, eight were female. Mean age was 72 years old (range 58=84). Three glenoid were type B2, six cases were B1, two case were type C1. Results. In all cases treated by reverse shoulder prostheses we had obtain good functional results at preliminary follow up. Eight degree posterior augment was used in seven case. Planned version was 0° in eight case, an anti-version of 3° was planned in the other three cases. Final reaming was as preoperatively planned in all cases except one. Mean surgical time was 71 minutes (range 51–82). One case of coracoid rupture has been reported. In all cases the system worked in proper manner without failures, no case of infection was reported. Discussion. It is well known as the more accurate placement of the glenoid led to enhanced long-term survivorship of the implant and decrease complication rates in RSTA. Our first experience with GPS navigation system has been satisfied. Good components’ positioning has been reached in all cases, without deviation from the preoperative planning. Pre-operative preparation using software has been always respected except in one case in which we decided to ream 1mm less to avoid excessive bone loss. In 3 case we decide to increase glenoid anti-version to allow a good cage containment in the scapula. No failure of the system has been recorded, with a little increase in the surgical time respect to traditional surgeries performed in our institute. The first case performed reported coracoid fracture, probably due to lack of experience in coracoid tracker positioning. It is very important to set the surgical theatre and the position of the patient in order to make the coracoid tracker visible for the computer. Screw positioning and length is decisively improved with GPS system compared with traditional implant. The most important advantage is to avoid the malposition of the glenoid component, solving problems like loosening or restriction in shoulder range of motion. We believe that a final cross check between preoperative planning and final control of the prostheses implanted, should be used in the future, but by now the GPS navigation system is a useful way to improve our surgery, especially in difficult cases. For any figures or tables, please contact the authors directly