We aimed to obtain anthropometric data on Korean knees and to compare these with data on commonly available total knee arthroplasties (TKAs). The dimensions of the femora and tibiae of 1168 knees were measured intra-operatively. The femoral components were found to show a tendency toward mediolateral (ML) under-coverage in small femurs and ML overhang in the large femurs. The ML under-coverage was most prominent for the small prostheses. The ML/anteroposterior (ML/AP) ratio of Korean tibiae was greater than that of tibial components. This study shows that, for different reasons, current TKAs do not provide a reasonable fit for small or large Korean knees, and that the ‘gender-specific’ and ‘stature-specific’ components help for large Korean femurs but offer less satisfactory fits for small femurs. Specific modifications of prostheses are needed for Asian knees

We investigated factors associated with postoperative lipiduria and hypoxemia in patients undergoing surgery for orthopedic fractures. We enrolled patients who presented to our emergency department due to traumatic fractures between 2016 and 2017. We collected urine samples within 24 hours after the patients had undergone surgery to determine the presence of lipiduria. Hypoxemia was defined as an SpO2 <95% determined with a pulse oximeter during the hospitalization. Patients’ anthropometric data, medical history, and laboratory test results were collected from the electronic medical record. Logistic regression analyses were used to determine the associations of clinical factors with postoperative lipiduria and hypoxemia with multivariate adjustment. A total of 144 patients were analyzed (mean age 51.3 ± 22.9 years, male 50.7%). Diabetes (odd ratio 3.684, 95% CI 1.256-10.810, p=0.018) and operation time (odd ratio 1.005, 95% CI 1.000-1.009, p=0.029) were independently associated with postoperative lipiduria, while age (odd ratio 1.034, 95% CI 1.003-1.066, p=0.029), body mass index (odd ratio 1.100, 95% CI 1.007-1.203, p=0.035), and operation time (odd ratio 1.005, 95% CI 1.000-1.010, p=0.033) were independently associated with postoperative hypoxemia. We identified several factors independently associated with postoperative lipiduria and hypoxemia in patients with fracture undergoing surgical intervention. Operation time was associated with both postoperative lipiduria and hypoxemia, and we recommend that patients with prolonged operation for fractures should be carefully monitored for clinical signs related to fat embolism syndrome

Introduction. Distraction histogenesis is utilised for cosmetic reasons in patients with constitutional short stature, achondroplasias, or height dysphoria. One of the considerations of patients and surgeons alike, is the preservation of aesthetically acceptable body proportions after the lengthening i.e which segment of the lower limb to lengthen and by how much, in order to preserve the patient's proportions within -or as close as possible to- the normal range of human body proportions. Sound anthropometric data on the normal range of the human body proportions is currently lacking. The aim of this study is to calculate the normal range of the ratio between the lengths of the lower limb, upper limb, femur, tibia, stature and trunk. Methods. Data form standardized measurements of the lengths of the tibia, femur, arm, stature, lower limb, upper limb was obtained from a sample population of 6068 healthy men and women servicing in the US Army. The mean, median, range and standard deviation were calculated for the following ratios of lengths: whole lower limb/leg, Stature/leg, Whole lower limb/thigh, Stature/thigh, Siting height/whole lower limb, Stature/Whole lower limb, Arm Span/Stature, Whole upper limb/Whole lower limb. Results. The ratios show normal distribution. Results are presented separately for men and women for the total sample population and for subgroups based on ethnic origin (White, Black, Hispanic and Asian). Discussion. This study is one of the first to provide specific anthropometric data from a large sample population relevant to the evidence-based preoperative planning and patient counselling before cosmetic limb lengthening procedures

Aim. This study aims to define the normal postoperative presepsin kinetics in patients undergoing primary cementless total hip replacement (THR). Methods. Patients undergoing primary cementless THR at our Institute were recruited. At enrollment anthropometric data, smocking status, osteoarthritis stage according to Kellgren and. Lawrence, Harris Hip Score (HHS), drugs assumption and comorbidities were recorded. All the patients underwent serial blood tests, including complete blood count, presepsin (PS) and C-Reactive Protein (CRP) 24 hours before arthroplasty and at 24-, 48-, 72- and 96-hours postoperatively and at 3-, 6- and 12-months follow-up. Statistical analysis was performed with SPSS v25.0 (SPSS Inc, Chicago, IL, USA). The Wilcoxon and Kruskal-Wallis tests followed by the Dunn multiple comparison post hoc tests were carried out. Correlations between PS, CRP and TOT were assessed using the Spearman rank correlation coefficient. P values below 0.05 were considered significant. Results and conclusion. A total of 96 patients were recruited (51 female; 45 male; mean age= 65.74±5.58) were recruited. The mean PS values were: 137.54 pg/ml at baseline, 192.08 pg/ml at 24-hours post-op; 254.85 pg/ml at 48-hours post-op; 259 pg/ml at 72-hours post-op; 248.6 pg/ml at 96-hour post-op; 140.52 pg/ml at 3-months follow-up; 135.55 pg/ml at 6-months follow-up and 130.11 pg/ml at 12-months follow-up. In two patients (2.08%) a soft-tissue infection was observed; in these patients higher levels (>350pg/mL) were recorded at 3-months follow-up. The lack of a presepsin decrease at 96 hours post-operatively should be a predictive factor of infection

Recently a great amount of research has been conducted into fatigability of paraspinal muscles in relation to Lower Back Pain (LBP). Additionally relationships have been observed between a general level of “fitness” and LBP. This research project aimed to evaluate the influence of aerobic fitness and health on lower back muscle function as measured by Electromyographic (EMG) spectral parameters. Participants undertake a series of psychometric tests, anthropometric data collection, EMG spectral analysis of the paraspinal muscles at lumbar and thoracic regions, and an aerobic fitness test. The EMG test involves a 30-sec isometric pull against a load normalised for weight. The spectral half-width, initial median frequency and median frequency slope are calculated. Participants are given biofeedback and exercise advice. Participants in this study were of above average fitness level compared to normative data. Other anthropometric data were similar to previous work conducted within this department. Preliminary regression analysis results have revealed no relationships between aerobic fitness level and EMG parameters, a finding that is counter to current beliefs on LBP and fitness, however it was observed that age did significantly influence lumbar spectral variable values (p = .002). A similar psychological profile was observed for all fitness levels

As for the number of patients who requires total knee arthroplasty (TKA), Asian-Pacific countries will be the most important market. However, due to the paucity of anthropometric data on the proximal tibia in this population, many prostheses designed for Caucasian knees have been introduced without specific modification.The aim of the current study was to analyze the geometry of the proximal tibia to design the optimum component for the Japanese population. Anthropometric data on the proximal tibia of 100 knees in 80 patients undergoing TKA was obtained. Briefly, anterior-posterior (AP) and medial-lateral (ML) lengths were measured with a combination of two different methods, namely on the computed tomography (CT) images obtained preoperatively and intraoperative direct measurement on tibial resection surface. Reproducible measurement was possible only when the intraoperative measurement was combined with the corresponding CT images while the direction of measurements being aligned to the epicondylar axis of the femur. It was shown that smaller components with an ML of around 60 mm were rarely required. Tibial component size variation should focus on an ML length of 65 to 75 mm because 76 of 100 knees (76 %) fell into this size range. When the subjects were confined to women, 70 of 77 knees (91%) were included in this size range. The intraoperative AP to ML ratio had a negative correlation with the ML length (r = −0.412, P < 0.0001) indicating that bigger knees were shallower in the AP direction. The size variation of currently popular pros-theses were not in accordance with the geometry of the tibial resection surface shown in this study. The results of this study applied to a cross-section of the Japanese population can be used by manufacturers to create a prosthesis suitable for most of the Asian-Pacific population

Introduction. Hip arthroplasty is considered common to patients aged 65 and over however, both Jennings, et al., (2012) and Bergmann (2016) found THA patients are substantially younger with more patients expecting to return to preoperative activity levels. With heavier, younger, and often more active patients, devices must be able to support a more demanding loading-regime to meet patient expectations. McClung (2000) demonstrated that obese patients can display lower wear-rates with UHMWPE bearing resulting from post-operative, self-induced reduced ambulatory movement, thus questioning if obese kinematics and loading are indeed the worst-case. Current loading patterns used to test hip implants are governed by ISO 14242-1 (2014). This study aimed to characterize a heavy and active population (referred to as HA) and investigate how the gait profile may differ to the current ISO profile. Method. A comprehensive anthropometric data set of 4082 men (Gordon, CC., et.al., 2014) was used to characterize a HA population. Obese and HA participants were classed as BMI ≥30 however HA participants were identified by applying anthropometric ratios indicative of lower body fat, namely “waist to height” (i.e. WHtR <0.6) and “waist to hip” (i.e. WHpR <0.9). Findings. Of 491 obese participants 61 were identified as HA (i.e. BMI> 30, WHpR<0.9; WHtR<0.6) (Figure 1). These characteristics were validated against a population of elite rugby players that were found to be a true reflection of HA patients (Figure 2). Combining the Army and Rugby populations resulted in a weight of 123kg for the 95. th. percentile, which based on 3× body weight (as referenced in ISO14242-1) would equate to a peak simulator load of 3620N. Conclusion. Characterization of a HA population was successfully defined as clinically obese by BMI, but with WHtR and WHpR associated with lower body fat. The author was unable to identify gait characteristics of a HA population through existing literature. Future Work. A gait-lab based study will be used to compare literature-based kinematics of obese subjects to those of HA subjects. A worst-case gait cycle can then be established for standard walking and other activities and translated into hip simulator parameters for HA patients

Designs of medical devices are tested for their mechanical behaviour, ability to transfer the load that is normally bore by the healthy tissue, and prove of the resistance to fatigue. The virtual testing in silico is widely accepted technique based on three sets of input data – geometry is normally obtained from CT or MRI scan as well as the tissue density that is translated into mechanical properties of the tissue. The virtual behaviour of the system is controlled by set of constrains accordingly while the third set of data consist of the load that system normally transfers through the load-bearing tissue. The magnitude and character of the load is highly dependent on the physical activity, external loads, physical condition of the subject and its specific factors such as gender, health condition, etc. Most of the published simulations use estimated simplified loads, which barely simulate the real behaviour of the system. The evaluation of the spinal load published some years back estimated a normal (N) and shear force (S) accompanied by the flexing moment (M). Due to lack of experimental possibility we used these data to test the biomechanical response of the lumbar segment with isotropic material models of all tissues. Then we investigated the possibility to evaluate muscular forces and their recruitment. It is a complex task and even today it is not possible to measure directly in vivo all muscular forces contributing to the movement. The musculo-skeletal system is a statically indeterminate system. The forces can be solved by means of computational modelling based on the measured trajectories of the body motion and additional optimization functions combined with static equations. The trajectories were recorded by the fast camera system in our motion laboratory and consequently exported into an open simulation software that uses a generic skeleton with around two hundreds muscle fascicles. The skeleton was scaled to correspond to our subject's anthropometric data and further scaling to mock-up the generic vertebrae was performed to eliminate discrepancies between the generic and subject's bones. Once these adjustments were done a kinematics and inverse dynamics modules were engage with selected objective function controlling the muscular recruitment that the max. relative muscular force is as small as possible. The 84 muscular forces acting on the segment were exported to a text file in APDL language and uploaded in the Finite Element (FE) database. The results of FE analysis were compared to the results obtained earlier using N,S,M load [1]. The comparison between the two models shows that the results of segment's total displacement was reduced by 36 percent compared to initial results. The stress and stress intensity increased six times. The identical model with orthotropic material showed reduced displacement by 80 percent and the stress and stress intensity was reduced by 60 percent compared to initial results

Introduction. The purpose of this study was to experimentally evaluate impingement and dislocation of total hip replacements while performing dynamic movements under physiological-like conditions. Therefore, a hardware-in-the-loop setup has been developed, in which a physical hip prosthesis actuated by an industrial robot interacts with an in situ-like environment mimicked by a musculoskeletal multibody simulation-model of the lower extremity. Methods. The multibody model of the musculoskeletal system comprised rigid bone segments of the lower right extremity, which were mutually linked by ideal joints, and a trunk. All bone geometries were reconstructed from a computed tomography set preserving anatomical landmarks. Inertia properties were identified based on anthropometric data and by correlating bone density to Hounsfield units. Relevant muscles were modeled as Hill-type elements, passive forces due to capsular tissue have been neglected. Motion data were captured from a healthy subject performing dislocation-associated movements and were fed to the musculoskeletal multibody model. Subsequently, the robot moved and loaded a commercially available total hip prosthesis and closed the loop by feeding the physical contact information back to the simulation model. In this manner, a comprehensive parameter study analyzing the impact of implant position and design, joint loading, soft tissue damage and bone resection was implemented. Results. The parameter study revealed a generally high dislocation risk for the seating-to-rising with adduction scenarios. Improper implant positioning or design could be compensated by adjusting prosthesis components correspondingly. Gluteal insufficiency or lower joint loading did not result in higher impingement or dislocation risk. However, severe malfunction of the artificial joint was found for proximal bone resection. Discussion. Previous testing setups ignored the impact of active muscles or relied on simplified contact mechanics. Herein, total hip replacement stability has been investigated experimentally by using a hardware-in-the-loop simulation. Thereby, several influencing factors such as implant position and design as well as soft tissue insufficiency and imbalance could be systematically evaluated with the goal to enhance joint stability

Introduction & aims. Different racial groups show variations in femoral morphometry. Femoral anteroposterior measurement and mediolateral measurement are key variables in designing femoral implant for TKR. Their aspect ratio determines the shape and mediolateral sizing for the proper patellofemoral tracking and uniform stress distribution over the resected distal femoral surface. Method. We reviewed the current literature in December 2013 in common medical databases including the Cochrane Library, PubMed and Medline. Keywords included combinations of: Anthropometry, Knee, Arthroplasty, Femur, Morphometry, Geometry. We selected papers including femoral morphometric data collected from populations of different ethnic origins. Papers covered populations in the USA, China, Germany, Thailand, Korea, India, Japan and Malaysia. Results. We have analysed femoral morphometry variables among different ethnic groups from the available data. Gross size of the resected femur can be defined in terms of antero-posterior (AP) and medio-lateral (ML) dimensions, an in the aspect ratio of femoral medio-lateral to femoral antero-posterior dimensions (fML/fAP). The Korean population showed the least value of fAP among all the groups, followed by Thai, Japanese, Indian, Malaysian and Chinese showing the increasing order among the sub-groups of Asian Population. American population shows the next higher fAP measurements from Asian population. German follows, and Arab quantify the largest value of this femoral anthropometric variable. fML varies by huge difference among male and female data in all populations. Thai, Indian, Malaysian, Arab, Japanese, Korean, German, Chinese and American; this sequence is the increasing order of fML. More trapezoid-shaped and narrower ML, this variation in female group leads to over-hang the implant for a given fAP. Generally, the aspect ratios are measured higher in these smaller female knees, and lower in larger male knees. Conclusions. Anthropometric data measuring distal femoral segment in different ethnic groups shows that the Asian population requires custom-fit implant design based on the morphological data. It would be more appropriate to introduce several medio-lateral options in sizing the implant for given antero-posterior dimensions

We report the outcome of 161 of 257 surgically fixed acetabular fractures. The operations were undertaken between 1989 and 1998 and the patients were followed for a minimum of ten years. Anthropometric data, fracture pattern, time to surgery, associated injuries, surgical approach, complications and outcome were recorded. Modified Merle D’Aubigné score and Matta radiological scoring systems were used as outcome measures. We observed simple fractures in 108 patients (42%) and associated fractures in 149 (58%). The result was excellent in 75 patients (47%), good in 41 (25%), fair in 12 (7%) and poor in 33 (20%). Poor prognostic factors included increasing age, delay to surgery, quality of reduction and some fracture patterns. Complications were common in the medium- to long-term and functional outcome was variable. The gold-standard treatment for displaced acetabular fractures remains open reduction and internal fixation performed in dedicated units by specialist surgeons as soon as possible

Introduction. Precise implant matching with a resected bony surface is a crucial issue to ensure a successful total knee arthroplasty (TKA). Extremely undersized or oversized components should be avoided. Therefore, we should measure the exact anthropometric data of the resected bony surface preoperatively or intraoperatively. The purpose of this study was to intraoperatively analyze the exact anthropometric proximal tibial data of Japanese patients undergoing TKA and correlate these measurements to the dimensions of current prosthetic systems. Patients and Methods. Three hundred and seventy-three knees in 299 Japanese patients were included in this study. There were 246 women and 53 men with a mean age of 74 (range: 63–85) years. All TKAs were performed by 3 senior surgeons (TS, AK, and NM). The bone cut in the proximal tibia was made perpendicular to the longitudinal axis of the tibia in the frontal plane. Intraoperative measurements of the proximal tibial cut surface were taken after proximal tibial preparation. Akagi's line (center of the posterior cruciate ligament tibial insertion to the medial border of the patellar tendon attachment) was adopted as the anteroposterior axis line of the proximal tibia. A mediolateral (ML) line was drawn perpendicular to Akagi's line. Then, anteroposterior (AP), lateral anteroposterior (lAP), and medial anteroposterior (mAP) lines were drawn as shown in Figure 1. Results. There was a significant positive correlation between lAP and ML dimensions. Although there also was a significant positive correlation between lAP and mAP dimensions, individual knees presented much scatter (Figure 2). The lAP dimension was smaller than the mAP dimension in all knees by a mean of 4.5 ± 1.9 mm. The proximal tibia exhibited asymmetry between the lateral and medial plateaus. The recent data of 177 knees indicated that Akagi's line was located 1.0 ± 1.2 mm medial to the AP line. A comparison of the morphologic data and the dimensions of the implants, one of which was a symmetric tibial component (NexGen: Zimmer, Warsaw, Indiana), and the other asymmetric (Genesis II: Smith & Nephew, Memphis, Tennessee), indicated that an asymmetric tibial component could be beneficial in maximizing the coverage of the tibial plateau. However, the size variation of the asymmetric tibial component was poor and the lAP and mAP dimensions showed much scatter; thus, we should measure the proximal tibia and choose the proper tibial component during surgery. Conclusions. This study provides important reference data that may be useful for designing proper tibial components for Japanese patients

Purpose: The purpose of the study is to measure the resected surface of femur of the Korean patients during total knee arthroplasty surgery and to compare these measurements with the dimensions of femoral implants in current use. Materials and Methods: Morphometric data (7 parameters) were obtained in 500 cases of resected femur of the Korean patients who underwent total knee arthroplasties, and these data were compared with four current implants designs. Results: The range of medial-lateral width at the given implant varies widely. The anterior width of the resected femur at the condyle is smaller than the widths of the most implants, creating an overhang. The medial-lateral width of the condyle at the level of transepicondylar line is wider than most of the present implants. However the widths of the resected posterior condyles were narrower at anterior-posterior alignment, causing overhang at the posterior condyles. We felt this will cause anterior tensioning at flexion and reduce the ability to flex further. Conclusion: The shape of the femur in Korean knee is different from that of current TKR implants in use, which are based on the anthropometric data of Caucasians. Therefore new design, better suited to the morphometric measurements of Korean knee, is necessary. Though historically this mismatch of the implant was well tolerated, new design to better fit the measurement of Korean knee should be considered for functional enhancement such as range of motion, durability and function

Most studies on LBP have focused on adults although many investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years. 688 students aged 16± 1 years from 5 randomly selected high schools participated in this multifactorial study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts. LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents. Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity

The purpose was to investigate back pain and disability and their relationship to vertebral changes in patients with untreated Scheuermann's. Overall, 136 patients who had attended the outpatient clinics between 1950 and 1990 for Scheuermann's were contacted, 49 of them (12 females, 37 males) responded. There was no difference in the baseline data between responders and non-responders. From radiographs, th-kyphosis, l-lordosis, and scoliosis were measured. The number of affected vertebrae and the degree of wedging were registered. Anthropometric data, occurrence of back pain, disability scores, and employment status were compared to a representative sample (n=3835) of the normal population. After mean follow-up of 37 (6.5;25.9-53.7) y, their average age was 58.8 (8.2;44.4.-79.3) y. Male patients were significantly taller than the control subjects. Female patients were on average 6 kg heavier (P=0.016) and their mean BMI was higher (23.9 kg/m. 2. vs 20.8 kg/m. 2. ,P=0.001) at age 20 than in the controls. Females had a greater mean kyphosis than males (51.7 vs. 43.2°, p=0.11). There was no correlation between the degree of thoracic kyphosis and disability. Scheuermann's patients had an increased risk for constant back pain (P=0.003), a 2.6-fold risk for disability because of back pain during the past 5 years (P=0.002), a 3.7-fold risk for back pain during the past 30 days (P<0.001), and a 2.3-fold risk for sciatic pain (P=0.005). They reported a poorer quality of life (p<0.001) and general health (p<0.001). There was no difference in working ability and employment status between patients and controls

Study design: Prospective multifactorial study on low back pain (LBP) in adolescents. Background data: Most studies on LBP have focused on adults although may investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years. Material and Methods: 688 students aged 16± 1 years from 5 randomly selected high schools participated in this study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. Results: LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts. Discussion: LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents. Conclusion: Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity

Introduction: The foot is a very complex structure acting as the platform for all gait patterns. At present, little is known about the exact biomechanics of the foot due to the difficulties in modeling all of the components of the foot accurately. This has made it virtually impossible to develop a complete understanding of the aetiology of many diseases of the foot including hallux rigidus. We hypothesize that sagittal plane incongruency of the rotation of the 1. st. Metatarsophalangeal Joint (MTPJ), or an increase in the tension of the intrinsic plantar flexors is responsible for the development of hallux rigidus. Materials & Methods: Ground reaction forces and kinematic data from gait analysis together with anthropometric data from MRI scans of a 24 y.o. female were used to create a Mimics model of the articulation of a normal 1st MTPJ during a gait cycle. The centre of rotation was calculated by triangulating the articular surfaces. Finite element analysis was performed on the model and on similar models with the hypothesized;. joint incongruency,. an increased tension in the Flexor Hallicus Brevis and. an increased tension in the plantar fascia. Results: The results demonstrated a significant increase in the peak stresses, contact areas and stress distributions between the incongruent models compared to the congruent models. Discussion: To the best of our knowledge this is the most accurate FE model of the 1st MTPJ calculated. Hallux Rigidus is a very common forefoot disorder, with multiple etiologies and treatments advocated. This model demonstrates that an increased tension in the plantar flexors results in a reduced ROM with increased contact stresses on the joint surface. Conclusion: While it is known Hallux Rigidus has a multi-factorial etiology, the authors feel the above study demonstrates an important inherent etiology

Aims

The aim of this investigation was to compare risk of infection in both cemented and uncemented hemiarthroplasty (HA) as well as in total hip arthroplasty (THA) following femoral neck fracture.

Aims

The purpose of this study was to evaluate the mid-term outcomes of autologous matrix-induced chondrogenesis (AMIC) for the treatment of larger cartilage lesions and deformity correction in hips suffering from symptomatic femoroacetabular impingement (FAI).

The incidence of acetabular fractures within the UK is about 3 in 100,000 of the population per year. Since Letournel and Judet first proposed that operative reduction and rigid internal fixation of displaced fractures will likely lead to better outcome, operative management of such fractures has become standard management in major trauma centres. Long term outcome results following acetabular surgery have been reported sparingly. Two hundred and fifty-seven displaced acetabular fractures underwent an open reduction and internal fixation at St. George’s Pelvic Unit between 1992 and 1997. All surgery was performed by a single surgeon. 161 patients were followed up prospectively for a minimum of 10 years. Those lost to follow up were excluded. Anthropometric data, fracture pattern, time to surgery, associated injuries, approach, complication and outcome recorded on a database. Modified Merle D’ Auberge score was utilized as outcome measures. The mean age was 36 years (15 to 85). Road traffic accident was the commonest mechanism of injury. We observed simple fractures in 34 % and associated fractures in 66%. 52% suffered polytrauma. Average time to surgery was 11 days and anatomic reduction was achieved in 73.9%. Results were excellent 46.8 %, good 25.5 %, fair 7.5 %, and poor 19.2 %. Poor prognostic factors were increasing age, delayed surgery, poor reduction, and posterior column, transverse posterior wall and T-shaped fracture patterns. Acetabular surgery poses a major challenge to the trauma surgeon. Complications in the immediate, mid and long term are not rare. Our results compare to other series with shorter follow-up. We believe that the gold standard treatment for displaced acetabular fractures must be open reduction internal fixation performed by a dedicated pelvic surgeon at the earliest time possible. Moreover whether we are merely postponing the inevitable post-traumatic arthritis is still unknown

Purpose. The majority (73%) of orthopaedic surgeons in Canada prefer using semitendinosus-gracilis (STG) autograft for ACL reconstruction. However, there is large variation in tendon size between individuals which makes pre-operative estimation of graft size unpredictable. Inadequate graft size may require an alternative source of graft tissue that should be planned prior to surgery. The purpose of this study is to determine if clinical anthropometric data and MRI measurements of STG tendons can be used to predict hamstring graft size. Method. One-hundred and fourteen patients with ACL deficiency awaiting reconstruction using hamstring autograft were retrospectively evaluated. The following information was obtained from patient charts: height, weight, body mass index (BMI), age, and gender. Cross-sectional area (CSA) of gracilis (G) and semitendinosus (ST) tendons were determined from pre-operative MRI scans using NIH ImageJ analysis software. Actual STG graft diameters were obtained from operative reports. Correlations between patient height, weight, BMI, age, gender, ST-CSA, G-CSA, STG-CSA and intraoperative graft size were calculated to determine the association between these variables. Multiple stepwise regression was performed to assess the predictive value of these variables to intraoperative graft diameter. In addition, three investigators with no radiological experience made independent measurements of the ST and G tendons to determine the inter-rater reliability (ICC) of MRI measurements. Results. All variables were independently correlated with intraoperative graft size (p<0.001). However, based on multiple stepwise regression analysis, only models including STG-CSA (r2=.212; p<.001); STG-CSA and sex (r2=.285; p<.001); and STG-CSA, sex and weight (r2=.294; p<.001) were found to be significant predictors of graft size (when co-variation in other factors was controlled). Inter-class correlation coefficients demonstrated very high agreement between raters for measurements of the ST, G and STG (.816, .827, .863, respectively). Conclusion. Measurement of tendon CSA from MRI images is very reliable. A model including STG-CSA, sex and weight was found to be strongly predictive of hamstring graft diameter for ACL reconstruction. This model may enhance our ability to predict adequate graft size and identify instances that other graft tissues may be a better option. The results of this study may improve pre-operative planning for ACL reconstruction

Purpose: There is no data concerning morphological dimensions of distal femur(DF), proximal tibia(PT) and thickness of patella(TP) in Indian population and our objective was to analyse the anthropometric data in Indian knees and to correlate them with existing knee arthroplasty systems. Methods: MRI scans of 25 patients(15M;10F) who underwent bilateral knee scans for ligamental injuries were collected. Patients with arthritis, bone loss, varus/ valgus deformity of > 150 and those with immature skeleton were excluded. The mean age was 32 years (range 18–53y). Three surgeons independently measured medio-lateral(ML), antero-posterior(AP) lengths & aspect ratio(AR) of DF, PT and TP on three occasions one week apart to account for intra & inter-observer variability. The resultant data of 50 knees was analysed using SPSS v16.0 and compared with five different knee arthroplasty systems (PFC sigma/NexGen/Scorpio/IB-II/ Gender specific knee). Results: The mean ML & AP for proximal tibia was 73.3±5.3 & 47.8±4.3 mm. The mean ML & AP (lateral condyle) for distal femur was 74.3±5.9 & 65.4±5.0 mm. The mean unresected thickness of patella was 24.7 & 21.8 mm in males & females respectively. The ML & AP showed a statistically significant positive correlation with person’s height (ML®=0.55;AP®=0.50 & p=0.01). A decrease in AR for increasing AP dimension was noted for both distal femur and proximal tibia (Tibia®=0.153;p=0.29 & Femur:®=−0.91;p=0.001). Discussion: None of the prosthesis designs mimicked this decrease in AR and NexGen infact showed increase in AR. Only Gender specific knee closely mimicked normal variation in AR and is available only for females (in India). Most of the available TKR prosthesis designs differ from true knee morphometry of Indian population. These data provides the basis for designing optimal prosthesis for people of Indian/Asian origin in UK/overseas

There is no data concerning morphological dimensions of distal femur, proximal tibia and patella in Indian population. The objective was to analyse the anthropometric data in Indian knees and to co-relate them with existing knee arthroplasty systems. MRI scans of 25 patients (15 males & 10 females) who underwent bilateral knee scans for ligamental injuries were collected. Patients with arthritis, bone loss, varus/valgus deformity of > 15 degrees and those with immature skeleton were excluded. The mean age was 32 yrs (18–53 yrs). Three surgeons independently measured medio-lateral (ML), antero-posterior(AP) dimensions & aspect ratio(AR) of distal femur, proximal tibia and unresected patellar thickness(PT) on three occasions one week apart to account for intra & inter-observer variability. The resultant data of 50 knees was analysed using SPSS v14.0 and compared with five prosthesis knee systems (PFC sigma, NexGen, Scorpio, IB-II & Gender specific knee). The mean ML & AP for proximal tibia was 73.3±5.3 & 47.8±4.3 mm. The mean ML & AP (lateral condyle) for distal femur was 74.3±5.9 & 65.4±5.0 mm. The mean PT was 24.7 & 21.8 mm in males & females respectively. The ML & AP showed a statistically significant positive correlation with the height of the person (ML r=0.55; AP r=0.50 & p=0.01). The tibial and femoral AR showed higher ratio for smaller knees & smaller ratio for larger knees i.e. decline in AR for increasing AP dimension. None of the prosthesis designs mimicked this decrease in AR and NexGen prosthesis infact showed an increase in AR. Gender differences in the morphological data were shown by variable tibial AR. Most of the available TKR prosthesis designs differ from actual knee morphometry of Indian population. These data provides the basis for designing optimal prosthesis for people of Indian/Asian origin in UK and overseas

Introduction. Despite extensive research, the cause of adolescent idiopathic scoliosis (AIS) is still largely unclear. Girls with AIS tend to be taller and leaner, and have a lower body-mass index (BMI) and lower bone mass, than do healthy girls. Recent MRI studies have shown the presence of relative anterior spinal overgrowth in girls with AIS. The lower bone mineral status and BMI could be related to dysfunctional central regulation pathway of growth, bodyweight, and bone metabolism. Following several interesting reports on the role of leptin in regulation of the above pathway in animals and human beings, our recent study has shown a low leptin concentration in girls with AIS girls compared with healthy adolescents. This finding leads to our new hypothesis that abnormal leptin bioavailability could be associated with the lower bodyweight, lower bone mineral density, and relatively disproportional endochondral skeletal growth in AIS. This study aimed to investigate the leptin bioavailability in girls with AIS. Methods. 53 girls with AIS and 27 healthy girls (aged 11–16 years) were recruited in this preliminary study. Clinical and anthropometric data were obtained. Blood samples were obtained for ELISA of leptin and soluble leptin receptor (sOB-R). Independent Student's t test and multivariate regression were used in group comparison. Results. The AIS group had significantly lower BMI and longer arm span than did controls. Additionally, girls with AIS had significantly higher soluble leptin receptor concentrations (22·1 ng/mL [□}6·9] vs 17·8 ng/mL [4·4]; p<0·01). However, the leptin concentration (7·6 ng/mL [□}5·3] vs 8·7 ng/mL [□}6·0]) and the leptin/sOB-R ratio (0·38 [□}0·28] vs 0·56 [□}0·47]) were similar to that of the controls. In girls with AIS, the leptin, sOB-R, and the leptin/sOB-R ratio correlated well with bodyweight and BMI. After adjustment for BMI, sOB-R in girls with AIS was significantly higher than in controls (r=0·37, p=0·042). Conclusions. This preliminary report showed that the soluble leptin receptor could be abnormal in girls with AIS. Leptin and sOB-R are related to bodyweight. sOB-R is a major modulator of leptin concentration in circulation, the abnormality of which may lead to the retention of leptin in the circulation and thus abnormal regulatory effect. In this study, girls with AIS had lower BMI and longer arm span, which may reflect the possible change resulting from abnormal leptin bioavailability. Further longitudinal study with larger sample size would be useful to help to understand the long-term effect of the low leptin and high sOB-R in girls with AIS on their bodyweight and skeletal development. It is also noteworthy to study the mechanism of increased sOB-R in AIS

The objective of this study was to determine if pre-operative gait patterns could predict which patients selected for unicondylar knee replacement (UKR) actually received a UKR or a total knee replacement (TKR). At the time of surgery, ten of the twenty-two UKR candidates presented with extensive degenerative changes and received total knee replacements. We analyzed gait, radiographic, and anthropometric data with a pattern recognition technique designed to detect biomechanical differences between the two groups. The groups were indistinguishable clinically, and radiographically, yet the pattern recognition technique identified features that completely separated the two groups based on the biomechanical differences. The objective of this study was to determine if pre-operative gait patterns could predict which patients selected for UKR actually received a UKR or a TKR. The UKR and TKR groups were indistinguishable visibly, clinically, and radiographically, yet the pattern recognition technique employed in this analysis identified features that completely separated the two groups. Biomechanical differences between the pre-operative groups could lead to more accurate diagnosis of unicompartmental knee OA as well as further understanding of the pathomechanics of knee OA. Twenty-two patients were initially diagnosed with unicompartmental knee OA of the medial side, and prescribed to receive unicompartmental knee replacements (UKR). At the time of surgery, ten of the twenty-two UKR candidates presented with more extensive degenerative changes and received total knee replacements (TKR). We measured gait data including knee joint angles forces and moments, velocity, stride length, stance percentage, and stance time as well as body mass index. Furthermore radiographic measures were taken including the Hip Knee Ankle (HKA) angle, the standing knee flexion angle, and the medial and lateral condyle joint spaces. The data were analysed using a pattern recognition technique that used principal component analysis to extract features from the data and discriminant analysis to separate the two groups. The discriminant function completely separated the UKR and TKR patients based on their pre-operative data. The most discriminatory feature represented a difference in early swing phase in the knee internal rotation moments

Introduction. Dislocation of total hip replacements (THRs) remains a severe complication after total hip arthroplasty. However, the contribution of influencing factors, such as implant positioning and soft tissue tension, is still not well understood due to the multi-factorial nature of the dislocation process. In order to systematically evaluate influencing factors on THR stability, our novel approach is to extract the anatomical environment of the implant into a musculoskeletal model. Within a hardware-in-the-loop (HiL) simulation the model provides hip joint angles and forces for a physical setup consisting of a compliant support and a robot which accordingly moves and loads the real implant components [2]. The purpose of this work was to validate the HiL test system against experimental data derived from one patient. Methods. The musculoskeletal model includes all segments of the right leg with a simplified trunk. Bone segments were reconstructed from a human computed tomography dataset. The segments were mutually linked in the multibody software SIMPACK (v8.9, Simpack AG, Gilching, Germany) by ideal joints starting from the ground-fixed foot. Furthermore, inertia properties were incorporated based on anthropometric data. Inverse dynamics was used to obtain muscle forces. Thus, optimization techniques were implemented to resolve the distribution problem of muscle forces whereas muscles were assumed to act along straight lines. For validation purposes the model was scaled to one patient with an instrumented THR [1]. Averaged kinematic measurements were used to obtain joint angles for a knee-bending motion. Then, the model was exported into real-time capable machine code and embedded into the HiL environment. Real implant components of a standard THR were attached to the endeffector of the robot and the compliant support. Finally, the HiL simulation was carried out simulating knee-bending. Experimentally measured hip joint forces from the patient [1] were used to validate the HiL simulation. Results. According to the joint angles obtained a knee-bending motion was carried out during the HiL simulation (Fig. 1). Predicted components of the hip joint force were in-between the envelopes of measured in-vivo data with partial deviation of the y-component (Fig. 2). The force application by the robot agreed well with the force values provided by the model. Discussion. Previous quasi-static mechanical setups for testing subluxation and dislocation of THRs neglected the impact of soft tissue structures on actual joint loading. Therefore, we combine the advantages of robot-based testing and numerical simulations within a HiL approach for dynamic analyses of THRs [2]. Thereby, validation is required to enhance the credibility of test results. The data presented demonstrate that the HiL test system with the embedded musculoskeletal model is capable of providing comparable THR loading as derived from in-vivo data. Certain deviations of the joint force's y-component will be the focus of up-coming model improvements. By considering dislocation-associated movements such as deep knee-bending, the influence of implant design and positioning on THR stability can be evaluated under reproducible, physiological-like conditions in subsequent studies

Introduction: Treatment of hip joint disease with Total Hip Arthroplasty (THA) is in continuous evolution with new approaches, new size of components and type of bearing surfaces. Meanwhile, the analyses of proven implants continues to yeld results with a high survivor-ship and almost absent osteolysis, even with the greater wear found in the poliethylene (PE) insert of 10 to 15 year old implants. The results of these THA and the need to revise some implants not loosened but with wear of the PE, is the object of this study. Methods: 330 non-cemented THA with the CLS expansion cup, performed by four surgeons over 15 years, are retrospectively analyzed. General anthropometric data of the studied population was obtained from medical records. Clinical elements are evaluated, among others the diagnosis, size and orientation of the components, time of partial/total weight bearing, period of crutch assisted walking, subjective patient satisfaction. X-rays were measured for numerical assessment of the orientation of the cup, migration, radiolucent lines, osteolysis and indirect evaluation of the wear of the PE insert. Obtained data recorded over the life of the implant was computed for correlations. Other studied elements include survival rate, complication, occurrence and type of revisions. Results: The encountered populations age was 62.7 +/− 10.9 years (Min 20, Max 86), the sex 43.1% male 56.9% female, the affected side 53.5% right 46.5% left. Charts of clinical elements, radiological measurements and correlation studies are presented. The wear of the PE insert correlates with the age of the implant and the inclination of the cup but not with radiolucent lines or osteolysis, which have a very low incidence. The complications and the survivorship analysis of the implants are presented and discussed. The encountered revision rate was 2.3% in the studied population. Without loosening, most revisions consisted on simple PE and head exchange. Conclusions: In the authors’ opinion, the very high rate of long-term survivorship with the CLS expansion cup makes this an excellent implant for THA. Even in the 10 to 15 year old group of implants presenting greater wear of PE, there is very low presence of osteolysis and low rate of loosening, permitting to perform simple exchange of the insert and head, a simple revision procedure that will allow quick functional recovery, high patient satisfaction and a good cost/efficiency relationship

Introduction: Bone resorption in the proximal femur is commonly seen after cementless total hip arthroplasty (THA). One of the main determinants of bone remodeling seems to be prosthesis design. With DXA, the amount of bone mass after THA can be precisely determined. We evaluated the BMD behavior of two different ultra-short implants with proximal load transfer, in order to study how a design can affect femoral bone remodeling. The rationale behind these designs is the experimental evidence that loading the medial and the lateral flare effectively preserves in time metaphyseal bone stock. Moreover, biomechanical tests have confirmed that this kind of stress distribution allows to remove the diaphyseal portion of the stem. Methods: A total of 33 patients operated with a cementless femoral implant were included in this study. Two slightly different designs were tested: Type 1 (Stanmore Orthopaedics), featuring an extremely short distal stem (n=10), and Type 2 (DePuy International Ltd), where distal stem was virtually absent (n=23). All implants were customized based on pre-operative CT data. The main features of these implants were the ultra-short stem and the large lateral flare. The rationale was to preserve bone stock and gain a more physiologic load transfer to the proximal femur thus preventing stress-shielding. DXA examination was performed on all patients 3 years after THA. Due to the peculiar design, a specific protocol of analysis with five regions of interest (ROI) was developed: ROI1 (greater trochanter), ROI2 and ROI4 (respectively lateral and medial of the ultra-short stem), ROI3 (below the tip) and ROI5 (calcar). The same protocol was applied to the non-operated contralateral femur and percentage contralateral BMD was calculated with the following formula: (BMD of operated hip/BMD of contralateral hip)×100. A standard DXA of contralateral hip and lumbar spine was also performed to evaluate the skeletal bone mineralization. Results: No differences were found in the anthropometric data and sex between the two groups. Age was found lower (p=0.001) in Type 2. BMD of lumbar spine and contralateral femur from standard DXA were not different in the two groups. BMD was higher in Type 2 in ROI4 and ROI5 (p< 0.001). The calculated percentage contralateral BMD was higher in Type 2 in ROI2 (p=0.009), ROI4 (p< 0.001) and ROI5 (p=0.01). Conclusions: This study confirms that progressive shortening of femoral stem produces a more proximal loading, which effectively preserves in time metaphyseal bone stock and increases periprosthetic BMD in the medial ROIs. The increased BMD in periprosthetic lateral and medial proximal regions in the operated hip respect to the contralateral femur seems to be due not only to the increased weight-bearing, but also to the specific ultra-short stem design

Introduction: Following an Australian study on the incidence of scoliosis in a population of short-statured children treated with human growth hormone (conducted during 2001–2002), it was determined that the only risk factor for the presence of idiopathic scoliosis was having Turner/another syndrome. The 30% incidence in Turner syndrome was noted to be much higher than previously reported (11–12%). The aim of this study is to determine the incidence of scoliosis in a group of growth hormone-treated and non-treated Turner Syndrome subjects who attended the International Turner Syndrome Society meeting in Sydney, Australia in July 2003 and to correlate the results with the Australian 2001–2002 results. Methods: 88 subjects were clinically examined for the presence and severity of idiopathic scoliosis. Their ages ranged from 11 to 60 years. All subjects provided information regarding previous growth hormone and/or oestrogen administration. Anthropometric data including sitting and standing height and arm span was also collated on this cohort. Results: 13 of 46 (28.3%) subjects who had no growth hormone treatment were found to have scoliosis. Five of 42 (12%) subjects who were growth hormone treated were found to have scoliosis. 12 curves were thoracic, five were thoracolumbar and one was lumbar. The 13 subjects with scoliosis and no growth hormone treatment had curves between10 and 20° Cobb angle. Three growth hormone-treated subjects had curves of 10°, one had a curve of 30° and the last subject had already undergone scoliosis surgery. Combining the results of this study with the three Australian States study from 2001–2002, 18 of 87 (21%) growth hormone-treated Turner syndrome subjects have idiopathic scoliosis. 13 of 46 (28%) non-growth hormone-treated Turner syndrome subjects also have idiopathic scoliosis. Of the total 133 subjects in this cohort, 31 (23%) have idiopathic scoliosis. Discussion: The incidence of idiopathic scoliosis in Turner syndrome appears to have been understated in previous studies. Data from this study would indicate that treating children who have Turner syndrome with adjuvant human growth hormone does not appear to result in a greater incidence or severity of idiopathic scoliosis. In this relatively small study, two of five children who had previous growth hormone treatment developed larger curves, one requiring corrective scoliosis surgery

The accurate assessment of skeletal maturity is essential in the management of orthopaedic conditions in the growing child. In order to identify the time of peak height velocity (PHV) in adolescents, two systems for assessing skeletal maturity have been described recently; the calcaneal apophyseal ossification method and the Sanders hand scores.

The purpose of this study was to compare these methods in assessing skeletal maturity relative to PHV. We studied the radiographs of a historical group of 94 healthy children (49 females and 45 males), who had been followed longitudinally between the ages of three and 18 years with serial radiographs and physical examination. Radiographs of the foot and hand were undertaken in these children at least annually between the ages of ten and 15 years. We reviewed 738 radiographs of the foot and 694 radiographs of the hand. PHV was calculated from measurements of height taken at the time of the radiographs.

Prior to PHV we observed four of six stages of calcaneal apophyseal ossification and two of eight Sanders stages. Calcaneal stage 3 and Sanders stage 2 was seen to occur about 0.9 years before PHV, while calcaneal stage 4 and Sanders stage 3 occurred approximately 0.5 years after PHV.

The stages of the calcaneal and Sanders systems can be used in combination, offering better assessment of skeletal maturity with respect to PHV than either system alone.

Cite this article: Bone Joint J 2015;97-B:1710–17.

In patients with severe quadriplegic cerebral palsy and painful hip dislocation proximal femoral resection arthroplasty can reduce pain, but the risk of heterotopic ossification is significant. We present a surgical technique of autologous capping of the femoral stump in order to reduce this risk, using the resected femoral head as the graft.

A retrospective study of 31 patients (43 hips) who had undergone proximal femoral resection arthroplasty with (29 hips) and without autologous capping (14 hips) was undertaken. Heterotopic ossification was less frequent in patients with autologous capping, and a more predictable pattern of bony overgrowth was found.

For a selected group of non-ambulatory patients with long-standing painful dislocation of the hip, we recommend femoral resection arthroplasty over more complicated reconstructive operations. The risk of heterotopic ossification, which is a major disadvantage of this operation, is reduced by autologous capping.

We describe the influence of the angle of immobilisation during partial weight-bearing on the forces across the extensor mechanism of the knee. Gait analysis was performed on eight healthy male subjects with the right knee in an orthotic brace locked at 0°, 10°, 20° and 30°, with the brace unlocked and also without a brace. The ground reaction force, the angle of the knee and the net external flexion movement about the knee were measured and the extensor mechanism force was calculated.

The results showed a direct non-linear relationship between the angle of knee flexion and the extensor mechanism force. When a brace was applied, the lowest forces occurred when the brace was locked at 0°. At 30° the forces approached the failure strength of some fixation devices. We recommend that for potentially unstable injuries of the extensor mechanism, when mobilising with partial weight-bearing, the knee should be flexed at no more than 10°.

Our aim in this pilot study was to evaluate the fixation of, the bone remodelling around, and the clinical outcome after surgery of a new, uncemented, fully hydroxyapatite-coated, collared and tapered femoral component, designed specifically for elderly patients with a fracture of the femoral neck.

We enrolled 50 patients, of at least 70 years of age, with an acute displaced fracture of the femoral neck in this prospective single-series study. They received a total hip replacement using the new component and were followed up regularly for two years.

Fixation was evaluated by radiostereometric analysis and bone remodelling by dual-energy x-ray absorptiometry. Hip function and the health-related quality of life were assessed using the Harris hip score and the EuroQol-5D.

Up to six weeks post-operatively there was a mean subsidence of 0.2 mm (−2.1 to +0.5) and a retroversion of a mean of 1.2° (−8.2° to +1.5°). No component migrated after three months. The patients had a continuous loss of peri-prosthetic bone which amounted to a mean of 16% (−49% to +10%) at two years. The mean Harris hip score was 82 (51 to 100) after two years.

The two-year results from this pilot study indicate that this new, uncemented femoral component can be used for elderly patients with osteoporotic fractures of the femoral neck.

We reviewed the outcome in 24 children with bilateral spastic cerebral palsy aged seven years or younger for whom surgery was recommended between 1999 and 2005 following gait analysis. A total of 13 children (operative group) had surgery and the remaining 11 (control group) did not, for family or administrative reasons. The operative group had at least two post-operative gait analyses at yearly intervals, with eight children having a third and six children a fourth. The control group had a second analysis after a mean interval of 1.5 years (95% confidence interval 1.1 to 1.9). In the operative group, the Gillette gait index, the ranges of movement in the lower limb joint and knee extension in stance improved following surgery, and this was maintained overall at the second post-operative analysis. The minimum knee flexion in stance in the control group increased between analyses.

These results suggest that surgical intervention in selected children can result in improvements in gait and function in the short to medium term compared with non-operative management.