Purpose. The purpose of this retrospective study was to investigate the acetabular morphology of pincer impingement hips in order to better understand damage pattern in these patients. We compared MRI measurements made at different postions from anterior to posterior on the acetbulum in patients with pure pincer type FAI to those made in patients with pure cam-type to collect parameters that may be useful in the diagnosis and classification of pincer impingement. Material and Methods. From an initial consecutive retrospective population of 1022 patients that underwent MRI with clinical impingement signs 78 hips which were selected with as clear cam (n=57) or pincer (n=21) impingement on plain radiographics. On these MR Imaging was performed with a 1.5-Tesla system. For analysis, a lateral angle of overcoverage on coronal MRI (MR_LCE), the MR extrusion index and the alpha angle (after Nötzli) were used. In addition to these the gamma angle, the acetabular depth and the angle of lateral acetabular overcoverage were described clock-wise on 7 radial slides from anterior to posterior. These were compared between the cam and pincer population using students-t-test. Measurements were obtained by two observers and inter-observer variability was assessed. Results. The acetabular depth showed in all 7 positions significant smaller values for pincer-type in comparison to cam-type impingement. Highest difference was found is superior-posterior position. The acetabular angle is also significant smaller for pincer than for cam in all radial positions. Highest difference of the acetabular angle is located in superior (pincer −102.93°/cam 109.62°) and anterior-superior position (pincer 102.48°/cam 108.77 °). The gamma angle showed significant differences in all radial positions except anterior position. The highest difference is located in superior-posterior position (pincer 86.18 °/cam 08.77°). The mean MR extrusion index was significant lower for pincer type (12.73%) compared to cam-type patients (17.76%) (p=0.004). LCE angle and extrusion index on MRI displayed a Person correlation coefficient of 0.920. The correlation of the acetabular depth and angle was 0.638. Conclusion. There are several morphological differences between pincer and cam acetabuli: They are significantly deeper in all radial positions than cam hips. They tend to have greater retroversion and have smaller gamma angles. Our results suggest that the superior-posterior quadrant displays greater coverage in pincer hips than cam hips, and therefore damage to the labrum and cartilage surface may extend further into the posterior portion of the acetabulum in pincer hips than in cam hips

Controversy remains as to whether the contralateral hip should be fixed in patients presenting with unilateral slipped capital femoral epiphysis (SCFE). This study compares the outcomes of those patients who had prophylactic fixation with those who did not. We identified 90 consecutive patients with a mean age of 12.3 years presenting to the study centre with SCFE from a prospective operative database. The patient's notes and radiographs were retrospectively analysed for post-operative complications, re-presentation with a contralateral slip, and the presence of a cam lesion. The mean length of follow-up was 8 years (range 3 to 13). Fifty patients (56%) underwent unilateral fixation and 40 patients underwent bilateral fixation, of which 4 (4%) patients had simultaneous bilateral SCFE and 36 (40%) had prophylactic fixation of the contralateral hip. Twenty-three patients (46%) that underwent unilateral fixation, went onto have contralateral fixation for a further SCFE. Two patients from this group had symptomatic femoracetabular impingement from cam lesions and one patient required a Southwick osteotomy for a severe slip. Five patients (10%) that had unilateral fixation only demonstrated cam lesions on radiographic analysis, being suggestive of an asymptomatic slip. No post-operative complications were observed for the contralateral hip in patients that had prophylactic screw fixation and no cam lesions were identified on radiographic assessment. This study suggests that the contralateral hip in patients presenting with unilateral SCFE should be routinely offered prophylactic fixation to avoid a further slip, which may be severe, and the morbidity associated with a secondary cam lesion

Introduction

Femoral neck fractures are an increasingly common injury in the elderly. Frequently these patients present taking Clopidogrel, an irreversible inhibitor of platelet aggregation. Although this is associated with an increased risk of intra-operative bleeding and also an increased risk of spinal haematoma where regional anaesthesia is employed, the recent SIGN (Scottish Intercollegiate Guidance Network) guidelines recommend that surgery should not be delayed.

Chronic plantar fasciitis is a common but sometimes difficult condition to successfully treat. Platelet rich plasma (PRP), a concentrated bioactive component of autologous blood that is rich in cytokines and other growth factors, was compared with cortisone injection in the treatment of severe cases of plantar fasciitis resistant to traditional non-operative paradigms. Thirty-six patients (16 males 20 females) were prospectively block-randomized into two study groups. All patients had pre-treatment MRI and ultrasound studies consistent with plantar fasciitis. The first group was treated with a single ultrasound guided injection of 40 mg Depo-Medrol at the injury site and the second group was treated with a single ultrasound guided injection of un-buffered autologous PRP at the injury site. The cortisone group had an average age of 59 (24–74) and had failed 4 months (3–24) of standard non-operative management (rest, heel lifts, PT, NSAIDS, cam walker immobilization, night splinting, local modalities) and had pre-treatment AOFAS scores of 52 (24–60). The PRP group had an average age of 51 (21–67) and had failed 5 months (3–26) of standard non-operative management (rest, heel lifts, PT, NSAIDS, cam walker immobilization, night splinting, local modalities) and had pre-treatment AOFAS scores of 37 (30–56). All patients were then immobilized fully weight bearing in a cam walker for 2 weeks, started on eccentric home exercises and then allowed to return to normal activities as tolerated and without support. Post-treatment AOFAS scores in the cortisone initially improved to 81(60–90) at 3 months but decreased to 74 (56–85) at 6 months. Post-treatment AOFAS scores in the PRP group improved to 95 (84–90) at 3 months and remained excellent at 94 (87–100) at 6 months follow-up. This study suggests that platelet rich plasma injection is more effective and durable than cortisone injection for the treatment of severe chronic plantar fasciitis refractory to traditional non-operative management

Introduction. Femoroacetabular impingement (FAI) is a relatively recent recognised condition and a potential cause of anterior hip pain in the young military adult population. Both Cam and Pincer type FAI may lead to inflammation, labral tears, and or damage to the smooth articular cartilage of the acetabulum leading potentially to early osteoarthritis of the hip. Open Surgical hip dislocation using the Ganz Trochanteric Flip approach is an accepted technique allowing osteoplasty of the femoral neck and acetabular rim combined with labral repair if required. We present our results of this technique used in military personnel. Methods. All Military personnel who underwent FAI surgery in our unit since August 2006 were included in the study. Functional outcome was measured using the Oxford hip and McCarthy non-arthritic hip scores pre and post-operatively. Results: 13 hips in 11 patients with an average age of 36 years (21–45) underwent surgical hip dislocation for treatment of FAI. Average time of downgrading prior to surgery was 9.3(3-18) months. 6 out of the 11 patients have been upgraded to P2. Average time to upgrading was 6.8(3-17) months. There were no infections, dislocations, or neurovascular complications. Mean Oxford Hip Score improved from 22.8(range 8–38) to 39.5(11–48) and mean McCarthy hip score from 49.6(33.75–80) to 79.2(36.25–100) with an average follow up of 19.4 months (range 4– 42 months). Discussion. The early results of surgical hip dislocation in military personnel are encouraging. Long-term follow-up is required to see if this technique prevents the natural progression to osteoarthritis

We hypothesised that an independent Notch Trial is essential on the same lines as other Component Trials-Femoral, Tibial and Patellar - in posterior stabilised total knee arthroplasty. Therefore we evolved Notch Trial to visually ascertain the adequacy of intercondylar resection and eliminate the possibility of femoral intercondylar fractures. We undertook a retrospective study to evaluate Notch Trial by the frequency of the need to remove osteophytes or file uneven surfaces in intercondylar resection by using the detachable box part of the trial femoral component, assess occurrence of distal femoral intercondylar fractures and demonstrate Notch Trial in posterior stabilised total knee replacement. We studied 206 patients, 113 females and 93 males, who underwent consecutive primary posterior stabilised total knee replacements applying Notch Trial between 2000 and 2008 in a District General Hospital under our team. Outcome Measurements were 1) frequency of the need to remove osteophytes or file uneven surfaces in intercondylar resection and 2) occurrence of distal femoral intercondylar fractures intraoperatively or on postoperative radiographs. We had to remove the osteophytes and file the cut surfaces in 183 (88.88%) of patients after Notch Trial. We had no distal femoral intercondylar fractures intraoperatively or on postoperative radiographs. Notch Trial allows the surgeon to directly visualise and ascertain the adequacy and precise fit of femoral notch cut with cam part of femoral component to ensure a press fit femoral component in condylar posterior cruciate substituting total knee replacement. Notch Trial prior to Femoral Component Trial effectively pre-empts intraoperative distal femoral intercondylar fractures. We recommend that Notch Trial should become part of the protocol for cruciate substituting total knee replacement and implants of all companies should have the option of a detachable box component for Notch Trial

Cam type femoroacetabular impingement (FAI) is due to an aspheric femoral head, which is best quantified by the alpha angle described on MRI and CT-scan. Radiographic measurement of the alpha angle is not well codified and studies from the literature cannot conclude on the best view to measure it. Most authors also describe a mixed type FAI which associates an aspheric femoral head with an excessive anterior acetabular coverage of the femoral head. Anterior center edge (ACE) angle has been described on the false profile view to measure anterior acetabular coverage in hip dysplasia and has never been evaluated in FAI. In this study, we developed a new lateral hip view which associates a lateral view of the femoral neck and a false profile view of the acétabulum, which we called profile view in impingement position (PVIP). Twenty six patients operated for FAI had CT-scan, the PVIP and the false profile view of one or two hips according to pain. A control group of 19 patients who did not suffer from the hip had the PVIP. Alpha angles were measured twice on 17 CT scan of FAI patients by two observers and compared with the alpha angles measured on the corresponding hip PVIP by a correlation analysis. Alpha angles were measured twice on 45 PVIP in FAI patient and on 19 PVIP in the control group by three observers. ACE angles were measured once on 15 PVIP and on 15 false profile views. Means were compared by two tail paired t-tests, intra- and inter-observer reliability were measured by intraclass correlation coefficient. Mean alpha angle on CT scan was 65.8° and 65.6° for observers 1 and 2 respectively (p>0.05). It was 63.6° and 64.3° on the PVIP (p>0.05). No significant difference was found between CT scan and radiographic measurements, and Pearson's correlation coefficients were good at 0.74 and 0.8. ICC was 0.86 for inter-rater reliability, and 0.91 for intra-rater reliability for CT-scan alpha angle measures. ICC for PVIP measures varied from 0.82 to 0.9 for intra-rater reliability and from 0.6 to 0.9 for inter-rater reliability. Mean alpha angle measured on PVIP in FAI patients was 63.3° and was 44.9° in control subjects and the difference was significant (p<0.001) for the three observers. None of the FAI patients and 88% of the control subjects had an alpha angle < 50°. Mean ACE angle was 26.8° on PVIP and 32.8° on the false profile view, the difference was significant (p=0.015), and the Pearson's correlation coefficient was moderate (r=0.58). The PVIP is a reliable radiographic view to measure the alpha angle. It allows a good quantification of the alpha angle comparable to CT-scan measurements and permits to differentiate patients from control subjects. PVIP is not a good view to quantify anterior edge angle probably because of acetabular retroversion due to the hip flexion needed in this view. Mean ACE angle measured on the false profile view in FAI patient was comparable to ACE angle in general population reported in the literature

INTRODUCTION. Analysis of retrieved ceramic components have shown areas of localized ‘stripe wear’, which have been attributed to joint laxity and/or impingement resulting in subluxation of the head, causing wear on the edge of the cup. Studies have been conducted into the effects of mild subluxation, however few in vitro tests have looked at severe subluxation. The aim of this study was to develop a more clinically relevant subluxation protocol. MATERIALS & METHODS. Seven (Subluxation n=4; standard test n=3) of 36mm Biolox Forte (R3, Smith & Nephew) ceramic devices were tested for 0.5m cycles (mc). Two of the subluxed joints were further tested to 1 Mc. The devices were subjected to subluxation under standard testing conditions. The flex/ext was 30° and 15° respectively, with internal/external rotation of ±10°. The force was Paul type stance phase loading with a maximum load of 3 kN, and a standard ISO swing phase load of 0.3 kN at 1 Hz. The test was conducted on a ProSim hip joint wear simulator (SimSol, UK). The simulator is equipped with a novel mechanism to achieve translation of the head, to achieve subluxation. During the ISO swing phase load of 0.3kN, a controlled lateral force required for the translation of the head is applied by a cam mechanism, head retraction then occurs during heel strike. The lubricant used was new born calf serum diluted with de-ionised water to achieve average protein concentration of 20 g/l, with 0.2 wt % concentration NaN3, and changed every 250k cycles. Measurements have been taken at 0.5 & 1 mc stages. RESULTS. Linear wear measurements conducted on the subluxed joints resulted in stripe wear similar to that reported in vivo. Average length, width and depth dimensions were 25.34±1.96 mm, 8±1.60 mm and 16.95±3.87 μm (± 95% CL) respectively. Linear wear at 0.5 Mc for standard joints, were undistinguishable from the original profile. Gravimetrically, weight loss was undetectable for joints tested under standard conditions. The volume loss of the joints under subluxation was 1.9± 0.7 mm3 at 0.5 mc. Two joints tested to 1mc generated an average volume loss of 3.1±2.3 mm3. The stripe wear length, width and depth at 1 Mc were 25.30±3.33mm, 8±3.92mm and 35±17.07 μm respectiveley. DISCUSSION. The current study presents test results of a hip joint simulator with a novel subluxation mechanism to simulate severe and clinically relevant hip joint. Past techniques have had to reduce the swing phase load to achieve stripe wear patches of varying size and depth. The subluxed joints produced significantly higher volumetric wear than the standard joints. Dimensional measurements in terms of length, width and depth of wear patches of subluxed joints generated similar results to that which have been observed following retrieval analysis. Tests that can simulate different types of activity in hip joint simulators will help to improve the design and understanding of implant behaviour in vivo