Reduced cervical spine canal AP diameter is linked to the development of spinal cord injury and myelopathy. This is of particular interest to clinicians in New Zealand, given a unique socio-ethnic make-up and prevalent participation in collision sport. Our study builds upon previous unpublished evidence, by analysing normal cervical spine CT scans to explore morphological differences in the sub-axial cervical spine canal, between New Zealand European, Māori and Paciāca individuals.

670 sub-axial cervical vertebrae (C3-C7) were analysed radiographically using high resolution CT trauma scans, showing no acute pathology with respect to the cervical spine. All measurements were made uPlising mulP-planar reconstruction software to obtain slices parallel to the superior endplate at each vertebral level. Maximal canal diameter was measured in the AP and transverse planes. Statistical analysis was performed using analysis of variance (ANOVA).

We included 250 Maori, 250 NZ European and 170 Paciāca vertebrae (455 male, 215 female). Statistically and clinically signiācant differences were found in sagittal canal diameter between all ethnicities, at all spinal levels. NZ European vertebrae demonstrated the largest AP diameter and Paciāca the smallest, at all levels. Transverse canal diameter showed no signiācant difference between ethnicities, however the raatio of AP:transverse diameter was signiācantly different at all spinal levels except C3. Subjective morphological differences in the shape of the vertebral canal were noted, with Māori and Paciāca patients tending towards a flatter, curved canal shape.

A previous study of 166 patients (Coldham, G. et al. 2006) found cervical canal AP diameter to be narrower in Māori and Paciāca patients than in NZ Europeans. Our study, evaluating the normal population, conārms these differences are likely reflecPve of genuine variation between these ethniciPes. Future research is required to critically evaluate the morphologic differences noted during this study.

Introduction

The accuracy of hexapod circular external fixator deformity correction is contingent on the precision of radiographic analysis during the planning stage. The aim of this study was to compare the SMART TSF (Smith and Nephew, Memphis, Tennessee) in-suite radiographic analysis methods with the traditional manual deformity analysis methods in terms of accuracy of correction.

Purpose

Degenerative changes of the lumbar motion segment often lead to stenosis of the spinal canal or neuroforamen. Axial lumbar interbody fusion (AxiaLIF) is intended to indirectly increase and stabilize foraminal dimensions by restoring disc height in patients with degenerative disc disease, thereby relieving axial and radicular pain. Therefore, this study investigated the effects of AxiaLIF on anterior disc height, posterior disc height, foraminal height and foraminal width as well as to determine the effectiveness of this minimally-invasive technique for indirect decompression and restoration of disc height.

Several studies have highlighted the relationship between anterior cruciate (ACL) injury and knee geometry particularly tibial slope (TS). However, clinical data are inconsistent, whether the lateral or medial or slopes have a different influence on ACL injury. Our goal was to assess whether the medial, lateral slopes are associated with ACL injury and whether meniscus geometry is associated with ACL injury. In addition, we sought to determine if lateral meniscal height could serve as a simple surrogate measurement for ACL injury risk. A case-controlled study compared 68 patients with an ACL injury and 68 matched nested controls. Radiological analysis of MRI measured the anterior-posterior distance of the medial and lateral plateaus, the tibial slope of both plateaus and meniscus geometry. Groups were compared using a Mann-Whitney test and α < 0 .05. The lateral tibial plateau slope was significantly higher in the ACL injured group (6.92 degrees ±5.8) versus the control group 2.68 ±5.26 (p 0.0001). In addition, the lateral meniscal slope was significantly steeper with (ACL injuries: −1 ±4.7 versus −4.73 ±4.4 (p 0.0001) in the control group. The ACL Injured group had a significantly lower lateral meniscal height 0.76 cm ±0.09, compared to the control group that has 0.88 cm ±0.12 (p 0.0001). The Lateral meniscal height had a sensitivity of 76.47% and specificity 75% for predicting ACL injury using a cut off of. Patients with ACL-injury had significantly higher lateral tibial plateau slope. Lateral meniscus height was found to be an easy measurement to make on MRI with a high specificity for predicting ACL injury. Lateral tibial slope and meniscal Geometry can be used to identify patients with high risk of an ACL injury, that might benefit from further surgery to optimize rotational stability in high-risk patients

Introduction. Pelvic tilt can vary over time due to aging and the possible appearance of sagittal spine disorders. Cup position in total hip arthroplasty (THA) can be influenced due to these changes. We assessed the evolution of pelvic tilt and cup position after THA and the possible appearance of complications for a minimum follow-up of ten years. Materials and methods. 343 patients received a cementless THA between 2006 and 2009. All were diagnosed with primary osteoarthritis and their mean age was 63.3 years (range, 56 to 80). 168 were women and 175 men. 250 had no significant lumbar pathology, 76 had significant lumbar pathology and 16 had lumbar fusion. Radiological analysis included sacro-femoral-pubic (SFP), acetabular abduction (AA) and anteversion cup (AV) angles. Measurements were done pre-operatively and at 6 weeks, and at five and ten years post-operatively. Three measurements were recorded and the mean obtained at all intervals. All radiographs were evaluated by the same author, who was not involved in the surgery. Results. There were nine dislocations: six were solved with closed reduction, and three required cup revision. All the mean angles changed over time; the SFP angle from 59.2º to 60º (p=0.249), the AA angle from 44.5º to 46.8º (p=0.218), and the AV angle from 14.7º to 16.2º (p=0.002). The SFP angle was lower in older patients at all intervals (p<0.001). The SFP angle changed from 63.8 to 60.4º in women and from 59.4º to 59.3º in men, from 58.6º to 59.6º (p=0.012). The SFP angle changed from 62.7º to 60.9º in patients without lumbar pathology, from 58.6º to 57.4º in patients with lumbar pathology, and from 57.0º to 56.4º in patients with a lumbar fusion (p=0.919). The SFP cup angle was higher in patients without lumbar pathology than in the other groups (p<0.001), however, it changed more than in patients with lumbar pathology or fusion at ten years after THA (p=0.04). Conclusions. Posterior pelvic tilt changed with aging, influencing the cup position in patients after a THA. Changes due to lumbar pathology could influence the appearance of complications at mid and long-term

Aim. Debridement and implant retention (DAIR) is a valuable option for treating periprosthetic joint infection (PJI), provided that the criteria of the Infectious Diseases Society of America guidelines are fulfilled. The inflammation caused by infection and the surgical impact of DAIR may influence implant stability. In this study, we investigated the sequelae of DAIR on implant survival after total hip arthroplasty (THA). Method. THAs from our database implanted between 1984 and 2016 were included in a retrospective double-cohort study. THAs were exposed (DAIR cohort) or not exposed to DAIR (control cohort). The control cohort comprised patients matched 3:1 to the DAIR cohort. The outcome—implant failure over time—was evaluated for (i) revision for any reason, (ii) aseptic loosening of any component, and (iii) radiographic evidence of loosening. Results. Fifty-seven THAs (56 patients) were included in the DAIR cohort and 170 THAs (168 patients) in the control cohort. The mean follow-up periods in the DAIR and control cohorts were 6.1 (SD 4.7) and 7.8 (SD 5.5) years, respectively. During follow-up, 20 (36%) patients in the DAIR cohort and 54 (32%) in the control cohort died after a mean of 4.1 (SD 4.7) and 7.2 (SD 5.4) years, respectively. Revision for any reason was performed in 9 (16%) DAIR THAs and 10 (6%) control THAs (p = 0.03) and for aseptic loosening of any component in 5 (9%) DAIR THAs and 8 (5%, p = 0.32) control THAs, respectively. Radiological analysis included 56 DAIR THAs and 168 control THAs. Two (4%) stems and 2 (4%) cups in the DAIR cohort and 7 (4%) and 1 (0.6%) in the control cohort, respectively, demonstrated radiological signs of failure (p = 1). Conclusions. THAs exposed to DAIR were revised for any reason more frequently than were THAs in the control cohort. The difference in revisions for aseptic loosening was not statistically significant. There was no statistically significant difference in radiographic evidence of loosening of any component between cohorts

The objective of this study was to evaluate the short term clinical and radiological results of a new short stem hip implant. In 29 consecutive patients suffering from osteoarthritis with 33 affected hip joints, the clinical and radiological results of 33 cementless hip arthroplasties using a cementless implanted short stem prosthesis type Aida and a cementless cup type Ecofit were evaluated prospectively between October 2009 and June 2015 in two hospitals. The median age of patients at time of surgery was 55 years (range, 30–71 years), 23 male and 10 female patients were included in the study. The median clinical follow up was 24 months (range, 1.5–51 months), and the median radiological follow up was 12 months (range, 1–51 months). Two patients were lost to follow up and two patients had only one immediate postoperative x- ray. The Harris Hip Score improved from a median preoperative value of 53 to a median postoperative value of 93 at follow up. Radiological analysis showed that 19 stems (58%) showed stable bony ingrowth, five cases (15%) showed stable fibrous ingrowth. Four cases need further follow up for proper evaluation of stem fixation. The short term survival of this new short stem is very promising, and achieving the goals of standard hip arthroplasty

Aim. The objective of this study was to evaluate the intermediate term clinical and radiological results of a new short stem hip implant. Methods. In 20 consecutive patients suffering from osteoarthritis with 25 affected hip joints (five cases were bilateral), the clinical and radiological results of 25 hip arthroplasties performed in one hospital between October 2009 and May 2014 through a minimally invasive anterolateral approach using a cementless short stem prosthesis type Aida and a cementless cup type Ecofit with a ceramic on ceramic pairing were evaluated prospectively. The median age of patients at time of surgery was 60 years (range, 42–71 years), 15 male (4 were bilateral) and 5 female patients (one was bilateral) were included in the study. The median clinical follow up was 30 months (range, 2–88 months), and the median radiological follow up was 30 months (range, 2–88 months). Results. Harris Hip Score improved from a median preoperative value of 53 to a median postoperative value of 96 (range, 73–100) at follow up. 22 hips (88%) showed an excellent postoperative Harris Hip Score, 2 hips (8%) a good postoperative Harris Hip Score, and one hip (4%) a fair postoperative Harris Hip Score. Only two patients complained of postoperative thigh pain. Regarding patient satisfaction, 15 patients (60%) were very satisfied, 10 patients (40%) were satisfied. None was unsatisfied. Radiological analysis showed that 19 stems (76%) were with stable bony ingrowth, two cases (8%) showed stable fibrous ingrowth. Four cases need further follow up for proper evaluation of stem fixation.(See Figures 1,2,3). Conclusion. The intermediate term survival of this new short stem is very promising, and achieving the goals of a standard hip arthroplasty. For any figures or tables, please contact the authors directly

Introduction. Although pelvic tilt does not significantly change after primary total hip arthroplasty (THA) at a short term, can vary over time due to aging and the possible appearence of sagittal spine disorders. Cup positioning relative to the stem can be influenced due to these changes. Purpose. We assessed the evolution of pelvic tilt and cup position after THA for a minimum follow-up of five years and the possible appearence of complications. Materials and methods. 47 patients underwent same single THA between 2008 and 2012. All were diagnosed with primary osteoarthritis and their mean age was 70.2 years (range, 63 to 75). There were 28 male patients, 19 had a contralateral THA, 17 were studied for lumbar pathology and three were operated for lumbo-sacral fusion. Radiological analysis included sacro- femoral-pubic and acetabular abduction angles on the anteroposterior pelvic view; and cup anteversion angle on the lateral cross-table hip view according to Woo and Morrey. All assessments were done pre-operatively and at 6 weeks, one, two and five years post-operatively. Three measurements were recorded and mean was obtained at all intervals All radiographs were evaluated by the same author, who was not involved in surgery. Results. There were four dislocations: one early and two contralateral dislocations which were solved wiith closed reduction, and one late recurrent dislocation five years after surgery which required cup revision. No other revision surgeries were performed. Mean sacro-femoral pubic angle decreased at all intervals from 60.6º preoperatively, to 60.0º at one year and 58.8 º at five years. This decrease was more significant in female, 63.3º preoperatively to 59.3º, than in male patients, 58.7º to 58.3º at five years. Mean acetabular abduction angle increased from 47.3º at 6 weeks to 48.2º at five years. Mean cup anteversion increased from 24.3º at 6 weeks to 26.4º at one year and 34.3º at five years. Conclusions. Posterior pelvic tilt increased with aging over time, particularly in women. These changes increased cup inclination and anteversion which may result in more dislocations after primary THA

Introduction. Bone loss management represents one of the most challenging issues for the orthopaedic surgeon. In most cases, stems, structural allograft, TMcones, and sleeves are adequate to allow optimal implant stability and durable fixation. In selected cases of wide metadiaphyseal bone defects, these devices do not provide proper intraoperative stability. In such scenarios, further steps are needed and include complex modular reconstruction, substitution with megaprosthesis (exposing patients at high risk of early failure) or joint arthrodesis that can yield unacceptable results. The aim of this paper is to present early results obtained with a new custom-made implant for complex metadiaphyseal bone defects management in knee revision surgery. By means of case presentations the authors would highlight the possibilities and technical notes of this novel device in complex knee revision surgery. Methods. Since2015, 8 custom-made porous titanium devices were implanted for massive bone defect management in 6 knee arthroplasty revision procedures. Five patients were staged revision for periprosthetic joint infection (PJI) and one patient underwent a staged revision for post-traumatic septic arthritis. Main demographic and surgical data were collected. Clinical (Range of Movement [ROM], Knee Society Score [KSS] and Oxford Knee Score [OKS]), radiological findings and complications were recorded at different time points and statistically evaluated. Mean follow up was 19.5 ± 9.6months. Results. The study group included 4 males and 2 females with a mean age of 63.7 ± 5.5 years and a mean Body Mass Index of 29.3 ± 4.1. Globally, the mean number of previous surgeries was 4.8 ± 2.7. The custom made device was combined with a hinged prosthesis in 5 cases and with a constrained condylar implant in 1 patient. Hybrid fixation was used in all cases. The mean KSS and OKS of the entire population improved significantly from 35.3 ±6.5 and 19.2 ±3.5 preoperatively to 85.8 ±4.0 and 39.3 ±3.1 at the time of last follow-up evaluation (p<0.01). The range of motion improved from 46.7 ±9.8 of mean preoperative flexion and 7.8 ±6.8 of mean preoperative flexion contracture to 93.3 ±10.3 and 1.2 ±2.9 respectively (p<0.01). Radiological analysis showed no migration or implant loosening. No intraoperative or postoperative complication was recorded. One patient required a prolonged antibiotic therapy for positive culture samples of sonication of the retrieved spacer. No implant mismatch between the preoperative planning and the final implant was reported. Conclusion. The presented custom-made implant showed promising early clinical and radiological results. In extremely selected cases, this new device can be considered a safe and effective surgical step between “off the shelf” reconstruction implants and knee substitution with a tumor megaprosthesis. Accurate surgical planning and intraoperative management of soft tissues and residual bone stock are of paramount importance

INTRODUCTION. Historically, the clinical performance of novel implants was usually reported by designer surgeons who were the first to acquire clinical data. Regional and national registries now provide rapid access to survival data on new implants and drive ODEP ratings. To assess implant performance, clinical and radiological data is required in addition to implant survival. Prospective, multi-surgeon, multi-centre assessments have been advocated as the most meaningful. We report the preliminary results of such a study for the MiniHip™femoral component and Trinity™ acetabular component (Corin Ltd, UK). METHODS. As part of a non-designer, multi-surgeon, multi-centre prospective surveillance study to assess the MiniHip™stem and Trinity™ cup, 535 operations on 490 patients were undertaken. At surgery, the average age and BMI of the study group was 58.2 years (range 21 to 76 years) and 27.9 (range 16.3 to 43.4) respectively. Clinical (Harris Hip Score, HHS) and radiological review have been obtained at 6 months, 3 and 5 years. Postal Oxford Hip Score (OHS) and EuroQol- 5D (EQ5D) score have been obtained at 6 months and annually thereafter. To date, 23 study subjects have withdrawn or lost contact, 11 have died, and 9 have undergone revision surgery. By the end of March 2018, 6 month, 1, 2, 3, 4, and 5 year data had been obtained for 511, 445, 427, 376, 296 and 198 subjects respectively. RESULTS. Implant revision rate is 1.68% (9/535), with revision for any reason as an endpoint; four of the nine involved the revision of the femoral component. At the 5-year time point, mean OHS had improved from 21.3 to 42.5 (p<0.01), EQ5D from 0.42 to 0.82 (p<0.01), and HHS from 51.6 to 92.5 (p<0.01). Radiological analysis is ongoing, and thus far has revealed more variation in stem alignment than is usually observed for more conventional length femoral components. This may indicate that optimal alignment of calcar loading short stems is different to that of longer, medullary canal aligned implants, consistent with the neck-stabilised design of the MiniHip™ stem. No other significant radiological findings were noted. During surgery, 31 calcar fractures were sustained, of which 20 were treated with cerclage wiring, 1 with femoral grafting and the remainder required no treatment. None of the hips with calcar fractures have been revised to date. DISCUSSION. The clinical and radiological performance of the MiniHip™ femoral stem is consistent with established femoral implants. Longer surveillance will determine whether this performance is maintained. Patients in this study will be continued to be followed-up and reviewed at the 7 and 10-year time points. CONCLUSION. The MiniHip™ stem is safe and efficacious at mid-term follow-up

Introduction. Implantation of total hip replacement (THR) remains a concern in patients with developmental dysplasia of the hip (DDH) because of bone deformities and previous surgeries. In this frequently young population, anatomical reconstruction of the hip rotation centre is particularly challenging in severe, low and high dislocation, DDH. The basic principles of the technique and the implant selection may affect the long-term results. The aim of the study was to compare surgical difficulties and outcome in patients who underwent THR due to arthritis secondary to moderate or severe DDH. Material and Methods. We assessed 131 hips in patients with moderate DDH (group 1) and 56 with severe DDH (Group 2) who underwent an alumina-on-alumina THR between 1999 and 2012. The mean follow-up was 11.3 years (range, 5 to 18). Mean age was 51.4 years in group 1 and 42.2 in group 2. There were previous surgery in 5 hips in group 1 and in 20 in group 2 (p<0.001). A dysplastic acetabular shape type C according to Dorr and a radiological cylindrical femur were both more frequent in group 2 (in both cases p<0.001). We always tried to place the acetabular component in the true acetabulum. Smaller cups (p<0.001), screw use for primary fixation (p<0.001) and bone autograft used as segmental reinforcement in cases of roof deficiency (p<0.001) were more frequent in group 2. Radiological analysis of the cup included acetabular abduction, version and Wiberg angles, horizontal, vertical, and hip rotation centre distances, and acetabular head index. Abductor mechanism reconstruction according to the lever arm distance and height of the greater trochanter was also evaluated. Cup placement within or outside Lewinnek´s safe zone was recorded. Two-way ANOVA with repeated measures were used to analyse clinical and radiological changes. Results. There were 6 cups revised for aseptic loosening, three in each group. Survivorship analysis at 15 years: 97.3% (95% IC 94.4–100) for group 1 and 93.0% (95% IC 85.2–100) for group 2 (p=0.186). Despite a worse preoperative status in group 2, the outcome improved similarly in both groups. Postoperative radiological measurements were better in group 1 except for acetabular acetabular and version angles. The improvement from the pre- to the post-operative situation was greater in group 2 except for the height of the greater trochanter. Acetabular component placement within the Lewinnek´s safe zone was similar in both groups. All revised cups were outside this zone. No osteolysis or complications related to the use of ceramics were found. Conclusions. The alumina-on-alumina THR provided good results in both groups including pain relief and functional improvement. Placing the acetabular component in the true acetabulum inside the Lewinnek safe zone can ensure a good result in these challenging dysplastic hips

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Aims

Distraction osteogenesis with intramedullary lengthening devices has undergone rapid development in the past decade with implant enhancement. In this first single-centre matched-pair analysis we focus on the comparison of treatment with the PRECICE and STRYDE intramedullary lengthening devices and aim to clarify any clinical and radiological differences.

Back ground. In 1970's, condylar type knee prosthese with anatomic design appeared, however, joint flexion was not satisfactory. Y/S II total knee arthroplasty (TKA) was developed to obtain deep flexion together with bilateral ligament balance in 1980. The articular surface of the tibial component was flattened to permit femoral shift posteriorily during knee flexion. Medial and lateral soft tissue release was determined by a unique ligament tensor both at flexion and extension. A metal tray was embedded in polyethylene, which had a shape of glasses frame. Though the usage of Y/SII TKA was finished in 1984, we here studied its long term surgical results using the Kaplan-Meyer method. Study design. From 1988 to 1991, 122 knees were replaced by Y/SII TKA in 81 patients with rheumatoid arthritis (RA). Among them, 24 joints in 12 patients were examined directly. The average age of follow-up was 19.5 years. The survival rate was investigated according to medical records. Results. The HSS knee score was 53.6 prior to the operation and 76.8 at the final observation. The average flexion was improved from 110.7degrees to 124.0 degrees after the operation, and was 115.8 degrees at the follow up. Radiological analysis showed no distinct clear zone around the femoral and tibial components. There was no breakage of components or polyethylene wear that cause a metal contact. The survival rate was 99% at 4 years and 97% at 19 years after the operation. Three prostheses were removed due to loosening in 2 and infection in 1. Discussion. While modern knee prostheses are designed to get deep flexion and long-term durability, the purposes of TKA in the earlier era were pain relief, stability and correction of deformity. Y/SII TKA was developed in such period, and obtained fairly deep flexion probably by its design and soft tissue release using the special instrument. Another result was that Y/SII TKA had long durability with a high rate of survival. One of the reasons was considered as the structure of femoral component. The metal tray with a shape of glasses frame conducts mechanical load anatomically to the bone and prevent from metal contact when polyethylene wears. The number of the size of component was only 3 and was fewer compared to current-generation prostheses. While this requires some technique when an operator inserts Y/SII prostheses, only a few instruments are needed during operation. Conclusively, we showed the good long term results of Y/SII TKA developed in relatively early era of knee prostheses

INTRODUCTION. The development of new bearing surfaces for total joint replacement is constantly evolving. Oxidized zirconium (Oxinium) has been introduced for use in both total hip arthroplasty (THA) and total knee arthroplasty (TKA). The aetiology of wear is multifactorial and includes adhesive, abrasive, third-body and fatigue wear mechanisms. Oxinium femoral components have demonstrated clear improvements in wear characteristics in-vitro. The purpose of this prospective study was to evaluate the mid-term (minimum 5 year) clinical and radiographic results and survivorship of the Genesis II™ knee implant system using an Oxinium femoral component. METHODS. Between January 2001 and December 2008, 382 Genesis II Oxinium (Smith & Nephew) primary total knee arthroplasties (TKA) (313 patients) were implanted at our institution. A comparison with a cohort of 317 patients (382 knees) who received a Genesis II knee implant using a ‘conventional’ cobalt-chrome (Co-Cr) femoral component was performed during the same time period. Prospective data was collected on all patients including demographics (age, BMI, diagnosis) as well as pre and postoperative clinical outcome scores (SF-12, WOMAC, and knee society clinical rating scores (KSCRS). Radiological analysis for evidence of osteolysis and loosening was performed in all patients. Comparisons were performed to determine differences between the Oxinium and Cobalt Chrome cohorts. Kaplan-Meier survival analysis was performed to show cumulative survival over time. Failure was defined as femoral component revision due to any cause. RESULTS. The mean age at time of surgery was 54.0 and 60.6 years respectively for the Oxinium and Co-Cr groups. The mean time from surgery was 8.13 +/− 2.03 years and 8.59 +/− 2.01 years for the Oxinium and Co-Cr groups respectively. Both groups demonstrated a statistically significant improvement in clinical outcome measures between pre, and post operative SF-12, WOMAC, and KSCRS scoring systems with no difference between two groups. There were a total of 15 revisions (infection: 8, stiffness: 2, aseptic loosening of patella component: 2, Aseptic loosening of the tibial component: 1, instability: 1, and one malaligned Femoral Component) in the Oxinium group. In the CoCr group there were a total of 9 revisions (Infection:5, aseptic loosening:1, instability: 1, stiffness: 1 and one patient revised for unexplained pain). Radiographically, no loosening was noted in the Oxinium group and all implants appeared well fixed. There was one case of loosening seen in the cobalt chrome group. The overall survival was 99.7 for both Oxinium and CoCr femoral components. Our study demonstrated no significant differences in validated clinical outcome scores and radiographic outcomes when comparing the Oxinium and Co-Cr femoral components. CONCLUSION. Despite the large numbers in our study, there were no statistically significant differences between Oxinium and CoCr femoral components at a minimum of five years follow up. While no clear benefits have been demonstrated, the use of an Oxinium femoral component demonstrated no adverse events at mid-term follow-up. Conventional Co-Cr femoral components remain the gold standard while long-term follow-up data is required to demonstrate the potential benefits of Oxinium

We report long term outcomes of the Rotaglide mobile bearing total knee arthroplasty (RTK). Method. Between 1995 and 1998, 61 RTK prostheses were implanted at our institution consecutively. Of 34 knees with a median duration to end of follow up of 13.0 years (range 11.4 to 14.2 years), the clinical result using Knee Society Score and radiological analysis using Knee Society Roentgenographic Sytstem was evaluated. Result. The prosthesis had an estimated survival probability of 94.1% at 13 years. There was one case of deep infection and one case of meniscal component failure. Clinical evaluation and knee function. The mean Knee score and function score at final follow-up are 90.0±8.3 and 61.8±29.6. The mean postoperative range of motion at final follow-up was from 0.7° (range 0–20°) to 117.8° (range 90–135°). Radiological analysis. The mean post operative FTA, aangle, ßangle, dangle are 173.8±3.9°, 96.4±2.2°, 90.9±3.1°, 81.3±2.9°. Clear zone was recognized in 2 tibia components but no progression was confirmed in the follow-up duration. Discussion. RTK is mobile bearing total knee which has a one piece meniscal component that is able to glide antero-posteriorly and rotate on the tibial component. Area contact between meniscal component and femoral component can be maintained from 0°to 90°of flexion. RTK gives satisfactory long-term clinical results. No knees were revised for aseptic loosening. This may be a result of the implant design

Total hip arthroplasty (THA) in teenagers is uncommon and previously associated with poor survival rates. However it is sometimes the only option remaining to relieve pain and improve function in patients with advanced hip disease. We report on the clinical and radiological outcomes of THA in teenage patients. Medical records and radiographs of all consecutive teenage patients undergoing THA at a tertiary referral centre between 2006–2011 were reviewed. Mean follow-up was 3.4 years (range 0.6–6.8) with 9 patients having at least 5 years follow-up. Post-operative Harris hip, Oxford hip (OHS) and University of California Los Angeles (UCLA) activity scores were recorded. 51 THAs were performed in 43 patients (21 male, 22 female) with a mean age of 17 years (range 12–19). The 5 most common indications were slipped upper femoral epiphysis osteonecrosis 15 (29.4%), developmental hip dysplasia osteonecrosis 5 (9.8%), multiple/spondylo-epiphyseal dysplasia 5 (9.8%), chemotherapy-induced osteonecrosis 4 (7.8%) and idiopathic osteonecrosis 4 (8.2%). 46 (90%) were uncemented THAs and 5 (10%) were reverse hybrid THAs with 7 computer assisted design/manufacture (CADCAM) femoral implants. Articular bearings were ceramic/ceramic in 40 (78.4%), metal/metal 6 (11.8%), metal/polyethylene 3 (5.9%) and ceramic/polyethylene 2 (3.9%). The survival rate was 96% with 2 acute head revisions for 1 sciatic nerve palsy and 1 instability. Other complications (8.2%) included 1 dislocation, 1 sciatic nerve palsy that resolved, 1 surgical site infection and 1 unexplained pain. At latest follow-up, the mean Harris hip score was 90 (68–99), OHS was 42 (32–48) and UCLA activity score was 6 (4–9). Radiological analysis showed 2 patients with lucent lines around the acetabular component, but no signs of osteolysis or wear. As one of the largest studies on teenagers undergoing THA, we report good clinical and radiological outcomes at short to intermediate term follow-up

Degenerate chondral surfaces can be assessed in many ways, but arthroscopy is often performed without proper categorisation, mapping, zoning or sizing of lesions. Progression of disease in un-resurfaced compartments is well-recognised to occur, but is only one of several failure mechanism in partial knee replacement. A validated ‘Functional Zone’ mapping method was used to document articular surface damage in 250 sequential cases of knee arthroscopy in patients over the age of 40. Size, shape, location and severity of each chondral lesion were noted using the Outerbridge classification. Analysis determined rates of involvement of particular compartments and assessed potential for partial replacement or local treatment and also to consider the risk of future progression. Radiographs including antero-posterior standing, postero-anterior flexion views (Rosenberg), lateral and skyline views were graded (Kellgren and Lawrence) and compared with the arthroscopic findings. Our results showed that out of the 210 knees with Grade 3 or greater damage 13.3% of knees showed ‘isolated’ medial disease of Outerbridge Grade 3 or worse. Isolated lateral disease was noted in 1.4%, patello-femoral disease in 24.3%, bi-compartmental (Medial/PFJ) disease in 30.9% with tibio-femoral and tri-compartmental disease seen in 15.2%. The combination of lateral and patello-femoral disease was seen in 14.8%. Provided that Grade 1 and 2 changes (which were found in other compartments in high percentages) were ignored and ACL status considered, this information seemed to indicate that at the time these procedures were performed, 13.3% of cases were suitable for a medial uni-compartmental device, with sub-analysis of lesion sizes indicating that 17 out of 28 cases (60.7%) were suitable for a localised resurfacing. Lateral uni-compartmental replacement seemed suitable for only 1.4%, patello-femoral replacement in 24.3%, bi-compartmental in 30.9% and total knee replacement in 30%. The mean age for partial resurfacing was 53years and 59 years for total joint replacements. Radiological analysis found that the antero-posterior standing views had only 66% sensitivity and 73% specificity for the presence of Grade 3 changes or worse in the medial compartment in comparison with Rosenberg views having a sensitivity of 73% and a specificity of 83%. Skyline views had a sensitivity of 56% and 100% specificity. This study indicates that a large proportion of cases may be suited to local and limited resurfacing. Cases suitable for Patello-femoral and Bi-compartmental replacements were very common, but with the patella-femoral joint's tendency to be more forgiving in terms of symptoms, meaning that indications for uni-compartmental replacement might well be much higher than the arthroscopic findings suggested. On the other hand, the presence of high levels of Grade 1 and 2 changes in other compartments seems to indicate a need for caution particularly in younger patients. This study also indicates a need for better methods of assessing local cartilage health such as enhanced MRI scanning or spectroscopy