Introduction: In this study we have studied the range of motion within Dynesys treated discs and levels adjacent to flexible stabilisation. Dynesys was designed to offer physiological motion at the lumbar spine. An advantage which is superior to abolishing movements through spinal fusion. Methods: A cohort of 75 post-Dynesys patients had weight-bearing lateral lumbar spine x rays in flexion/extension positions. Evaluation was done through PACS™ digital software. Flexibility at individual disc level was measured as the differences between flexion/extension angles accurate to within 1°. Motion was evaluated at the index and immediate adjacent levels. Results: Patients with single level Dynesys had an average ROM of (3+/−4.7) at L5-S1 and (5.1+/−2.9) at the immediate adjacent level. Two levels Dynesys was associated with a ROM of 5+/−3.6 at L5-S1 & L4–5 and 3.5+/−1.8 at their immediate neighbour disc. Across three levels, Dynesys favoured a ROM of 5.3+/−2.5 at the operated sites and 1.6+/− 2 at the adjacent level. Discussion & Conclusion: This study is the first radiological research to confirm the flexibility of Dynesys. Controlled motion at the dynesys treated disc levels share to distribute global spinal movements. This will advantage the next disc segments and protects them from risk of developing “accelerated adjacent segment disease”

There is still want of evidence in the current literature of any significant improvement in clinical outcome when comparing computer-assisted total knee arthroplasty (CA-TKA) with conventional implantation. Analysis of alignment and of component orientation have shown both significant and non-significant differences between the two methods. Not much work has been reported on clinical evidence of stability of the joint. We compared computer-assisted and conventional surgery for TKA at 5.4 years follow-up for patients with varus osteoarthritic knees with deformity of more than 15∗. Our goal was to assess clinical outcome, stability and restoration of normal limb alignment. We used CT and Cine video X ray techniques to analysize our results in Computer navigated and conventional TKRs. A three dimentional CT scan of the whole extremity was performed and evaluation was done in three planes; saggital, coronal and transverse views. CT scan was done between 10 to 14 days postoperative. Mean deviations in the mechanical axis, femoral and tibial plateau angles, and in transverse view, the trans-epicondylar axis vs posterior condylar axis were measured. The prospective randomized study comprised of 98 patients with surgery done on knees, one side navigated and other side conventional. Mean deviation in the mechanical axis was 2.2∗ in conventional knees and 1.8∗ in navigated knees. In 5 % of cases retinacular release was needed and CT analysis showed TEA in deviation of more than 2 ∗ in these cases. We analysed intraoperative data (surgical time and intraoperative complications), postoperative complications, lower limb alignment, radiographic complication on X-ray imaging, and clinical outcome throughknee and function score, range of motion and joint stability. Our results showed that CAS had greater consistency and accuracy in implant placement and stability of joint in full extension and 90∗ flexion. In the coronal view, 93.3% in the CAS group had better outcomes compared with EM (73.4%). In the sagittal axis, 90.0% CAS also had better outcomes compared with EM (63.3%). Computer-navigated total knee arthroplasty helps increase accuracy and reduce “outliers” for implant placement

Introduction: Occult fractures of carpal bones are underestimed. To be treated succesfully fractures of the scaphoid must be identified at an early stage. A delay in detection may result in non union. We validated with 3 prospective studies a new tool using scintigraphy : The quantitative Xray bone scan (QRS). Material and Methods: A previous preliminary prospective study with 60 patients was performed and published to valid the QRS as a step in diagnosis of wrist occult bones fractures equal to RMI. This exam is a bone scan with 2 improvments. 1) A quantification of the fixation spot : If the spot is two times more important on the injuried wrist (than controlateral side) the fracture is sure. 2) If you combine plain Xrays of the the wrist with scintigraphy the fracture is automatically located. This previous report pointed that repeat set of scaphoid views, dynamic and static, Ct scan, proved unsuitable for screening occult fractures of the wrist. Result: Between november 97 and march 04, 667 patients were enrolled in a prospective continue study. 40% (260/667) of patients with an injury of the wrist with normal X ray sustained an occult fracture. QRS was performed at an average of 17,7 days after the injury and after clinical exam and repeat set of scaphoid view. Scaphoid fractures were most frequent. Fixation was most important if scintigraphy was performed between 11 and 20 days after the injury. Fixation did not depend on age, sex, volume of the bone, and delay (after 15 days). Discussion: As Dikson, Dias, Thompson, and Kuckla, repeat set of scaphoid view are unable to improve significativally the number of occult fractures of the wrist. RMI as reported by Kuckla can reduce the need for further imaging procedure. RMI and scintigraphy are both the best exam to diagnose surely an occult fracture of the wrist. But QRS does not over diagnose, as RMI, bones fracture’s. Conclusion: “Plaster cast and wait” is not the treatment for occult carpal bones fracture’s. The quantitative Xray bone scan is able to diagnose such fractures with short delay

Background

Using digital X-rays to plan a hip replacement can cause problems with sizing and templating the prosthesis. Using an AP view of both hips is desirable as this allows the use of the sometimes unaffected contralateral hip for templating.

Aim of the study: The aim of the study was to register and þnd out the longterm femoral bone response after insertion of femoral stem with or with-out cement. Materials and methods: Seventeen patients (7 men, 10 women) underwent cemented and 22 patients (14 men, 8 women) uncemented total hip arthroplasty (THA). The mean age in the cemented group was 69 (58–74) years and in the uncemented group 58 (46–68) years. Femoral bone mineral density (BMD) was measured using Lunar DPX or Lunar DPX-IQ densitometry according to zones by Gruen (ROI 1–7). BMD measurements were made preoperatively, and postoperatively over four to 14 days, and at 3, 6, 12, 24, and 36 months after THA. Postoperative BMD changes were calculated using the immediate postoperative BMD value as a reference, the change being expressed as a percent. Results: Peri-prosthetic BMD decreased signiþcantly almost in all ROIs during the þrst three months after both cemented (5–18%) and uncemented (3–14%) THA (p-values < 0.05 to p< 0.001). At the end of the þrst year the most remarkable decrease in BMD was found in the calcar (zone 7) in both groups (cemented 25%; uncemented 23%). Low preoperative bone loss predicted higher periprosthetic bone loss in both groups. From one to three year only small changes in periprosthetic BMD were detected after THA. Conclusions: The present study suggests that postoperative bone loss is equal after uncemented and cemented THA. The bone loss is most pronounced during the þrst six months after THA and mainly associated in proximal femoral bone. After the phase of acute bone loss, further loss is minimal after uncomplicated THA, reßecting merely the normal aging of bone. Patients with poor bone quality at baseline are at higher risk to lose bone around the prosthesis after THA.

Purpose

To evaluate Radiological changes in the lumbosacral spine after insertion of Wallis Ligament for Foraminal Stenosis.

To evaluate Radiological changes in the lumbosacral spine after insertion of Wallis Ligament for Foraminal Stenosis.

Thirty two Levels in Twenty Six patients were followed up with standardised radiographs after insertion of Wallis Ligaments for Foraminal Stenosis. Wallis ligaments as a top-off or those with prolapsed discs were not included. The Radiological parameters compared were Anterior and Posterior Disc height, Foraminal height and width, The inter-vertebral angle (IVA), Lumbar lordosis and Scoliosis if any. The presence of slips and their progression post-op was noted, as was bony lysis if any.

There were ten males with thirteen levels and sixteen females with nineteen levels in the study. Eighteen levels (56.25%) were L4/L5, ten (31.25%) were L5/S1 and 4 (12.5%)were L3/L4. The average age in the series was 59.6 years (Range 37 – 89 yrs). Average follow up was 9.5 months (Range 2 to 36). The Average increase in Anterior disc height was 1.89 mm (+/−1.39), the posterior disc height increased by an average 1.09 mm (+/−1.14). Foraminal height increased by an average 3.85 mm (+/− 2.72), while foraminal width increased by 2.14 mm (+/− 1.38). The IVA increased in 16 and reduced in 15 patients, with no change in 1. Lumbar Lordosis increased in 23 patients, with an average value of 2.3°. No patient exhibited progression in scoliosis and no lysis could be identified. There were three Grade I slips pre-op; none progressed.

Foraminal dimensions and Disc height were consistently improved after Wallis insertion. Changes in IVA and Lumbar lordosis were however variable. A longer follow up is suggested to look for sustained improvement and the presence of lysis.

Aims and objectives

Our aim was to evaluate the indications for patients undergoing magnetic resonance imaging (MRI) of the knee prior to referral to an orthopaedic specialist, and ascertain whether these scans altered initial management.

Neck of femur fractures are a common presentation and certain patients can be managed with a total hip replacement. To receive a total hip replacement the pelvic X-rays should be templated as per AO guidelines and a common way this is performed is by including a calibration marker on the X-ray. The aim of this study is to assess and improve upon the use of the calibration marker. Details of patients admitted with a neck of femur fracture from January 1st 2018 until December 31st 2018 were gathered and used to review each initial X-ray and determine if a calibration marker was included. 376 patients were admitted with a neck of femur fracture over the one year period. 36% of patients did not have a calibration marker on their initial pelvic X-ray and 11% did not have a chest X ray. 215 patients had an intracapsular fracture and 39 went on to have a total hip replacement. 12 patients were lacking a calibration marker on their original X ray and required a repeat X ray. After a poster was placed in the radiographer booth acting as a visual aid, the use of a calibration marker improved from 62% to 70%. Calibration markers are useful tools which can aid the pre-operative planning for hip replacement surgeries shortening operative time, increase precision and reduce prosthetic loosening, lowers the risk of peri-prosthetic fractures, reduce leg length discrepancy and ensure the required implants are available. If a marker is not included on the initial X-rays, and a patient has a neck of femur fracture which requires a joint replacement, they may have to have additional X-rays performed as was the case for 12 patients in this study. This process leads to possible delays in surgery, additional radiation and increased healthcare costs

Aims: Irradiated allograft bone may help to reduce the risk of transmission of infectious agents from donor to recipient. The purpose of this study was to establish the results of impaction bone grafting of acetabular defects with froze, irradiated allograft bone. Methods: All patients treated by a single surgeon with impaction bone grafting of acetabular defects at revision total hip replacement were reviewed retrospectively. All operations were performed during the period 1994–2000. The mean follow-up was 50 months (range 30–96 months). Case notes and X rays were reviewed and analysed. The Paprosky grade of acetabular defects was determined from the pre-operative X rays and the surgeonñs operation note. Post-operative X rays were reviewed to establish the extent and rate of new bone in-growth. Functional outcomes were determined by way of self-administered questionnaires. Results: Complete records and X rays were obtained for 33 patients who underwent revision hip arthroplasty with impaction bone grafting of the acetabulum using frozen, irradiated allograft bone. There were no complications associated with the bone grafts and no patient required a re-operation. Review of serial X rays conþrmed in-growth of host bone and the functional outcome was satisfactory. Overall 29 patients (88%) declared themselves satis-þed with the outcome of their operation and 32 patients (97%) improved functionally after the operation. Conclusions: These results indicate that satisfactory results can be achieved with impaction bone grafting using frozen, irradiated allograft bone. The use of irradiated bone graft can potentially reduce the risk of disease transmission from donor to recipient without compromising the surgical results

The aim is to investigate if there is a relation between patellar height and knee flexion angle. For this purpose we retrospectively evaluated the radiographs of 500 knees presented for a variety of reasons. We measure knee flexion angle using a computer-generated goniometer. Patellar height was determined using computer generated measurement for the selected ratios, namely, the Insall–Salvati (I/S), Caton–Deschamps (C/D) and Blackburne–Peel (B/P) indices and Modified I/S Ratio. A search of an NHS hospital database was made to identify the knee x rays for patients who were below the age of forty. A senior knee surgeon (DC) supervised three trainee trauma and orthopaedics doctors (HA, JM, ES) working on this research. Measurements were made on the Insall–Salvati (I/S), Caton–Deschamps (C/D) and Blackburne–Peel (B/P) indices and Modified I/S Ratio. The team leader then categorised the experimental measurement of patients’ knee flexion angle into three groups. This categorisation was according to the extent of knee flexion. The angles were specifically, 10.1 to 20, 20.1 to 30, and 30.1 to 40 degrees of knee flexion. Out of the five-hundred at the start of the investigation, four hundred and eighteen patients were excluded because they had had either an operation on the knee or traumatic fracture that was treated conservatively

Background. An improved understanding of intervertebral disc (IVD) structure and function is required for treatment development. Loading induces micro-fractures at the interface between the nucleus pulposus (NP) and the annulus fibrosus (AF), which is hypothesized to induce a cascade of cellular changes leading to degeneration. However, there is limited understanding of the structural relationship between the NP and AF at this interface and particularly response to load. Here, X-ray scattering is utilised to provide hierarchical morphometric information of collagen structure across the IVD, especially the interface region under load. Methodology. IVDs were imaged using the I22 SAXS/WAXS beamline at Diamond Light Source. Peaks associated with the D-banded structure of collagen fibrils were fitted to quantify their azimuthal distribution, as well the magnitude and direction of internal strains under static and applied strain (0–20%). Results. IVD tissue regions exhibited structural “AF-like” and “NP-like” fingerprints. Demonstrating high internal strains on collagen fibres particularly within the NP region of the disc. AF and NP regions showed distinct collagen orientation and internal strains with an apparent lack of bracing structure seen at the interface between the differential mechanical tissues. X-ray scattering under tensile strain provided structural information at high resolution, with clear differences observed between normal and degenerate discs under load. Conclusion. X ray scattering has been utilised to develop an improved understanding of collagen structure across the intervertebral disc which can be utilised to gain an increased understanding of load induced propagation of micro fissures and disc degeneration. Conflict of Interest: No conflict of interest. Funding: BioPro Network, UCL for funding this study through support from the MRC (MR/R025673/1)

Aim: Assessing Polyethylene wear is very important in following up patients after Total hip replacement (THR) and Livermore method (using callipers) is routinely used by clinicians in calculating this wear. Our aim was to assess if ‘Imagika’, a new computer software programme can accurately assess polyethylene wear(PE-wear). We also compared the computer software with the Livermore method in calculating wear. Method: We used 15 different THR X rays of patients who had an ABG total hip replacement done. X rays that were included for the calculations were taken at different time intervals following the operation. Wear was calculated on each X ray by 3 clinicians using both the methods, on 3 separate occasions. We compared the Livermore method and the computer software for consistency of measurements and also calculated the inter and intra observer variability for both. Results: There was a statistically significant difference (at the 5% level) between the measurements taken by the Imagika software and the Livermore method. F(1,88) = 5.38, p< 0.05. There was a statistically significant difference in the inter-observer measurements using the Livermore method. F(2,42) = 4.18, p< 0.05, but there was no significant inter-observer variation using the Imagika computer software. There was no statistically significant difference (at the 5%level) in the intra-observer variability of both groups. Conclusion: The Imagika computer software proved to be better than the Livermore method in calculating wear with regards to inter-observer bias. There was also a significant difference between measurements taken using both methods. We conclude that the computer software may be a more accurate tool in the assessment of PE-wear in the future

Introduction: A good cup positioning requires reliable anatomical landmarks expecially for navigation. The anterior pelvic plane (APP) seems to be a good reference for navigation because it is in relation with pelvic tilt which do affect the position of the cotyle and consequently the position of the cup. The value of this plane is not well known according to gender, age, weight… The aim of the study is to assess radiologically the APP in standing and supine position before and after total hip arthroplasty. MATERIALS AND Methods: 92 Patients (32 males, 60 females, mean age 65 years) underwent strict lateral X-rays in standing and supine standardized position. Uninterpretable or unsatisfying X rays were withdrawn. 45 patients underwent a standing X-ray, 24 a supine X-ray, 21 a supine and standing X ray. Statistical analysis used a Student t-test. Results: Non matched values showed a retroversion of the pelvis of 6.4° (+/− 6.9) in supine position, 0.3° (+/− 7.4) in standing position. Matches values showed an retroversion of the pelvic of 6.9° (+/− 5.3) in supine position, 0.3° (+/− 5.03) in standing position (significant difference). Extreme values varied from −15° to + 18° (3 patients showed no variation, 2 patients a retroversion from supine to standing position). There was no statistical difference between male and female but a statistical differences in females. Discussion: The APP is easily assessable by X rays in standing as in supine position. Bony landmarks of the plane are also assessable by navigation tools and to can be a good plane as reference. Several authors showed the repercussion of the pelvic tilt on the cotyle position. The difference between standing and supine position is about 6°. But for some patients the difference is may be of 20°and that could explain some impigment and instability. A cup well positioned in supine position may be not so good in standing position because of the pelvic tilt. Conclusion: The value of the APP is important to know before THA and seems to be a good plane as reference for navigation

Patients with osteoarthritis of the knee reviewed by the General practioners, are usually referred for further management to the orthopaedic surgeon. It was our observation that patients were usually referred with supine knee X-rays. This meant weight-bearing films were repeated at the clinic. Methods: We sent out questionnaires to GPs inquiring whether they asked for X-rays of the knee prior to patient referral and whether they asked for weight bearing films. We also reviewed the policy in one National Hospital Service trust and one teaching hospital with regards to GPs asking for weight bearing films. The time patients spent waiting at the X-rays department was noted. Finally we inquired about the cost of a knee X-ray. Results: A total number of 65 questionnaires were sent and the response was 44 i.e. 67%. 80% of the GPs asked for non weight bearing X-rays prior to referral. Only 5% asked for weight bearing films. The radiology departments of hospitals in one NHS trust and the teaching hospital did not accept weight bearing requests from GPs. The time taken for a patient to get an X ray in the department was at least 30 minutes and the cost of X rays of the knee was £51. With an average of two patients with osteoarthritis of the knee per clinic, the cumulative waiting time for repeated X-rays was 1 hr per clinic, 5 hrs per week and 240 hrs per year. With an average of two X rays per clinic the cumulative cost was £102 per clinic, £510 per week and £24480 per year. Discussion: Non weight bearing X-rays of the knee do not add any value in making or confirming a diagnosis of osteoarthritis yet they are costly both in terms of time and money. Weight bearing films were repeated for patients with these X-rays. The cumulative cost in terms of time can be better used to review other patients and therefore reduce the waiting time before surgeons can see referrals. The other issue is the cumulative cost which can be put to better use in the trust. The time wasted by the patients who have repeated X-rays was not considered, but is also of importance. Conclusion: Patients with osteoarthritis of the knee should have weight bearing films from the initial onset. This will save time for the patient and the surgeon and will save the hospital money

The best follow up strategy after hip replacement (THR) is unclear. There are conflicting demands to obtain early diagnosis of loosening, and to minimise clinic visits. It would be desirable to achieve follow up with a validated symptom questionnaire alone, but it is unclear how frequently THRs are asymptomatic during early loosening. This study examined the relationship between patient reported symptoms after THR using two measures (Oxford Hip Questionnaire (OHQ) and Visual Analogue Scale (VAS)), and the classification of the patients AP x ray of the hip as having definite loosening, possible loosening, or a sound implant. We examined data from 325 patients who had undergone a standard Charnley THR for osteoarthritis. Patients had a mean follow-up of 85 months (range 24–144). X rays were examined by a single Consultant Orthopaedic surgeon, and classified as satisfactory, possible loosening or definite loosening. As expected, the large majority of patients had a satisfactory appearance on x-ray at all-time points. 12 patients were classified as having definite loosening on the basis of the available x-rays. 8 of these were subsequently listed for revision surgery at review. 20 patients were noted to have evidence of possible loosening. Examination of the Oxford hip questionnaire and VAS data demonstrated a strong relationship between OHQ value and the VAS result for pain (r = 0.78, p < 0.001, Spearman rank correlation). Data were analysed separately (using ROC curves) to determine whether the OHQ or VAS was a satisfactory method of selecting patients who fell into “definite loosening” or “definite or possible loosening” groups. Neither OHQ or VAS were sensitive or specific for definite or possible loosening. We conclude that x rays are required for early detection of loosening, and that follow up by OHQ or VAS alone is insufficient for this purpose

Introduction. Magnetic resonance arthrogram (MRA) is the investigation of choice in young adults with symptoms of femero acetabular impingement. The aim of the study is to assess the accuracy of MRA when correlated with surgical findings on hip arthroscopy. Materials and Method. Between June 2007 and January 2014, 136 patients had MRA followed by subsequent arthroscopy at our institution. The radiology information system was used to gather MRA data. All scans were reported by a consultant radiologist with a specialist interest in musculoskeletal radiology. Patient records were reviewed to gather surgical data. Assessment was made of labral injury, Camshaft (CAM) or Pincer lesion and degeneration of the cartilage. Results. Mean age at MRA was 34.5 years with a 2.5:1 female to male ratio. For labral pathology sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 89, 100, 100 and 22% respectively. For CAM (62, 80, 79 and 64% respectively) and Pincer lesions (15, 84, 81 and 18% respectively). MRA was specific for picking up Grade 3/4 degenerate changes in the articular cartilage (92.2%) but was not as sensitive (60%), PPV 55 and NPV 94. Conclusion. These findings demonstrate that MRA is a sensitive and specific imaging modality for assessing the labrum and articular surface, but not as good for assessing CAM and Pincer lesions. This could be due to the static nature of the MRA or a lack of firm definition as to what constitutes a CAM or Pincer lesion leading to under reporting. This maybe better assessed with plane X ray or Computed tomography with 3 dimensional reconstruction. Further to this it would be interesting to combine the plane X ray and MRA finding and see if sensitivity and specificity was improved

Introduction and Objective. Malunion after trauma can lead to coronal plane malalignment in the lower limb. The mechanical hypothesis suggests that this alters the load distribution in the knee joint and that that this increased load may predispose to compartmental arthritis. This is generally accepted in the orthopaedic community and serves as the basis guiding deformity correction after malunion as well as congenital or insidious onset malalignment. Much of the literature surrounding the contribution of lower limb alignment to arthritis comes from cohort studies of incident osteoarthritis. There has been a causation dilemma perpetuated in a number of studies - suggesting malalignment does not contribute to, but is instead a consequence of, compartmental arthritis. In this investigation the relationship between compartmental (medial or lateral) arthritis and coronal plane malalignment (varus or valgus) in patients with post traumatic unilateral limb deformity was examined. This represents a specific niche cohort of patients in which worsened compartmental knee arthritis after extra-articular injury must rationally be attributed to malalignment. Materials and Methods. The picture archiving system was searched to identify all 1160 long leg x ray films available at a major metropolitan trauma center over a 12-year period. Images were screened for inclusion and exclusion criteria, namely patients >10 years after traumatic long bone fracture without contralateral injury or arthroplasty to give 39 cases. Alignment was measured according to established surgical standards on long leg films by 3 independent reviewers, and arthritis scores Osteoarthritis Research Society International (OARSI) and Kellegren-Lawrence (KL) were recorded independently for each compartment of both knees. Malalignment was defined conservatively as mechanical axis deviation outside of 0–20 mm medial from centre of the knee, to give 27 patients. Comparison of mean compartmental arthritis score was performed for patients with varus and valgus malalignment, using Analysis of Variance and linear regression. Results. In knees with varus malalignment there was a greater mean arthritis score in the medial compartment compared to the contralateral knee, with OARSI scores 5.69 vs 3.86 (0.32, 3.35 95% CI; p<0.05) and KL 2.92 vs 1.92 (0.38, 1.62; p<0.005). There was a similar trend in valgus knees for the lateral compartment OARSI 2.98 vs 1.84 (CI −0.16, 2.42; p=0.1) and KL 1.76 vs 1.31 (CI −0.12, 1.01; p=0.17), but the evidence was not conclusive. OARSI arthritis score was significantly associated with absolute MAD (0.7/10mm MAD, p<0.0005) and Time (0.6/decade, p=0.01) in a linear regression model. Conclusions. Malalignment in the coronal plane is correlated with worsened arthritis scores in the medial compartment for varus deformity and may similarly result in worsened lateral compartment arthritis in valgus knees. These findings support the mechanical hypothesis that arthritis may be related to altered stress distribution at the knee, larger studies may provide further conclusive evidence

Introduction. One of the important criteria of the success of TKR is achievement of the Flexion ROM. Various factors responsible to achieve flexion are technique, Implant and patient related. Creation of the Posterior condylar offset is one such important factor to achieve satisfactory flexion. Aim. To correlate post op femoral condylar offset to final flexion ROM at 1 yr. post op. Methods. This is a clinico-radiological study of the cases done prospectively between September 2011 and August 2012. Inclusion criteria:. All patients undergoing Bilateral TKRs and have agreed for the follow up at 1 yr. Exclusion criteria:. Patients who had previous bony surgery on lower end femur. Patients with previous fracture of lower end femur. All the patients had PS PFC Sigma (De Puy, Warsaw) components cemented. ROMs were measured at 6 weeks, 3 months, & 1 year post op. The last reading was taken as final flexion ROM as measured by a Physiotherapist with the help of a Goniometer. Results. We had 21 cases of Bilateral TKRs who satisfied our criteria. Pre and post op femoral condylar offset was measured in mm. on lateral x ray. Pre and post op flexion was measured. Results showed that variation in the posterior femoral offset by > 3mm in post op x ray was related to loss of flexion of an average 21 deg. (16 – 24 degrees). Greater the deflection from the normal offset, greater was the loss of flexion. These patients also showed lesser improvement in KSS functional score. Discussion. Flexion is one of the most important yardsticks for the measurement of success of TKR. This factor is more important more so in Asian population. Literature has shown that three important determinants for good flexion are…. Posterior Condylar Offset Restoration. Tibial slope restoration. Femoral Roll back in flexion. An increased offset permits greater flexion before impingement between the tibial insert and the femur. In our study we kept Tibial slope and Femoral Roll back constant by using the same prosthesis. The femoral condylar offset changed as per the size of the AP femoral cutting block. (Anterior referencing guide used). Overresection of the posterior condyles reduced the posterior femoral condylar offset and hence significant loss of post op flexion. The shorter posterior condyle of smaller femoral component can increase the potential for bone impingement proximal to the posterior condyles. In our study the opposite side replaced knee acted as a control. It is generally stated that after a TKR flexion can improve upto 1 year and hence was taken as final possible flexion. Conclusion. Keeping Tibial slope and Femoral roll back constant during the surgery, posterior condylar offset restoration within 3 mm of its original pre op offset was necessary to achieve satisfactory flexion at 1 year. Undersizing the femoral component to achieve more flexion is perhaps suboptimal. Appropriate AP femoral sizing is a must to restore the normal offset

Aims: Functional results of anterior cruciate ligament (ACL) is closely related to the anatomical position of the graft. Femoral or tibial miss placements are associated with increase laxity, decrease range of motion. Based on anatomical dissections we developed a triangle method able to be used as fluoroscopic intra-operative landmark to increase the reproductibility of the placements. Methods: A lateral X ray of normal knee is mandatory before the surgical procedure. During the ACL reconstruction using patellar tendon a pin is placed to determine the tibial tunnel, and a small screw is inserted at the femoral ACL location. Under imagine intensifier, a lateral X ray of the operated knee is realised. The picture is exported and analysed on a PC computer. The surgical placement is compared with the ACL center position according to the triangle method. 35 knees have been operated and compared with 35-paired knees operated with the same technique and operator. Results: The mean distance between the ACL center and the surgically chosen femoral position is 7.5 ± 1.9 mm for the standard surgery and 4.9 ± 1.3 mm for the fluoroscopy based surgical navigation. The Wilcoxon test for small-paired series indicates a statistical significance (p=0.001). The mean extra operative time is 15 ± 7mn. Conclusion: This technique is simple, easy and rather fast. It gives to the surgery a significative improvement for positioning the ACL graft on the femoral side. It has to be confirmed for larger and by long term clinical results