Total temporomandibular joint (TMJ) replacements reduce pain and improve quality of life in patients suffering from end-stage TMJ disorders, such as osteoarthritis and trauma. Jaw kinematics measurements following TMJ arthroplasty provide a basis for evaluating implant performance and jaw function. The aim of this study is to provide the first measurements of three-dimensional kinematics of the jaw in patients following unilateral and bilateral prosthetic TMJ surgeries. Jaw motion tracking experiments were performed on 7 healthy control participants, 3 unilateral and 1 bilateral TMJ replacement patients. Custom-made mouthpieces were manufactured for each participant's mandibular and maxillary teeth, with each supporting three retroreflective markers anterior to the participant's lip line. Participants performed 15 trials each of maximum jaw opening, lateral and protrusive movements. Marker trajectories were simultaneously measured using an optoelectronic tracking system. Laser scans taken of each dental plate, together with CT scans of each patient, were used to register the plate position to each participant's jaw geometry, allowing 3D condylar motion to be quantified from the marker trajectories. The maximum mouth opening capacity of joint replacement patients was comparable to healthy controls with average incisal inferior translations of 37.5mm, 38.4mm and 33.6mm for the controls, unilateral and bilateral joint replacement patients respectively. During mouth opening the maximum anterior translation of prosthetic condyles was 2.4mm, compared to 10.6mm for controls. Prosthetic condyles had limited anterior motion compared to natural condyles, in unilateral patients this resulted in asymmetric opening and protrusive movements and the capacity to laterally move their jaw towards their pathological side only. For the bilateral patient, protrusive and lateral jaw movement capacity was minimal. Total TMJ replacement surgery facilitates normal mouth opening capacity and lateral and inferior condylar movements but limits anterior condylar motion. This study provides future direction for TMJ implant design

Aims. The first aim of this study was to evaluate whether preoperative renal function is associated with postoperative changes in whole blood levels of metal ions in patients who have undergone a Birmingham Hip Resurfacing (BHR) arthroplasty with a metal-on-metal bearing. The second aim was to evaluate whether exposure to increased cobalt (Co) and chromium (Cr) levels for ten years adversely affected renal function. Methods. As part of a multicentre, prospective post-approval study, whole blood samples were sent to a single specialized laboratory to determine Co and Cr levels, and the estimated glomerular filtration rate (eGFR). The study included patients with 117 unrevised unilateral BHRs. There were 36 females (31%). The mean age of the patients at the time of surgery of 51.3 years (SD 6.5), and they all had preoperative one-, four-, five-, and ten-year laboratory data. The mean follow-up was 10.1 years (SD 0.2). Results. Median Co levels at one year postoperatively increased significantly compared with the preoperative values, by a factor of 9.7, from 0.13 to 1.26 ppb (p < 0.001), and the median Cr levels increased significantly by a factor of 2.5, from 0.60 to 1.50 ppb (p < 0.001). Lower preoperative eGFRs were associated with significantly larger increases in Co at one year compared with the preoperative levels (ρ = -0.26; p = 0.005), but there was no relationship between preoperative eGFRs and changes in Cr at one year (ρ = -0.13; p = 0.153). Metal levels remained relatively constant with the passage of time, with a median ten-year value of 1.12 ppb for Co and 1.29 ppb for Cr. There was no significant relationship between the Co and Cr levels at ten-year follow-up and the change in eGFR from the preoperative level to that at ten years (ρ = -0.02; p = 0.827 for Co; ρ = -0.008; p = 0.933 for Cr). Conclusion. Although patients with lower preoperative eGFRs tended to have larger increases in Co levels at one year, increased metal levels for patients who underwent unilateral BHR did not adversely affect renal function during the first ten postoperative years. Cite this article: Bone Joint J 2024;106-B(3 Supple A):44–50

Aims. Morphological abnormalities are present in patients with developmental dysplasia of the hip (DDH). We studied and compared the pelvic anatomy and morphology between the affected hemipelvis with the unaffected side in patients with unilateral Crowe type IV DDH using 3D imaging and analysis. Methods. A total of 20 patients with unilateral Crowe-IV DDH were included in the study. The contralateral side was considered normal in all patients. A coordinate system based on the sacral base (SB) in a reconstructed pelvic model was established. The pelvic orientations (tilt, rotation, and obliquity) of the affected side were assessed by establishing a virtual anterior pelvic plane (APP). The bilateral coordinates of the anterior superior iliac spine (ASIS) and the centres of hip rotation were established, and parameters concerning size and volume were compared for both sides of the pelvis. Results. The ASIS on the dislocated side was located inferiorly and anteriorly compared to the healthy side (coordinates on the y-axis and z-axis; p = 0.001; p = 0.031). The centre of hip rotation on the dislocated side was located inferiorly and medially compared to the healthy side (coordinates on the x-axis and the y-axis; p < 0.001; p = 0.003). The affected hemipelvis tilted anteriorly in the sagittal plane (mean 8.05° (SD 3.57°)), anteriorly rotated in the transverse plane (mean 3.31° (SD 1.41°)), and tilted obliquely and caudally in the coronal plane (mean 2.04° (SD 0.81°)) relative to the healthy hemipelvis. The affected hemipelvis was significantly smaller in the length, width, height, and volume than the healthy counterpart. (p = 0.014; p = 0.009; p = 0.035; p = 0.002). Conclusion. Asymmetric abnormalities were identified on the affected hemipelvis in patients with the unilateral Crowe-IV DDH using 3D imaging techniques. Improved understanding of the morphological changes may influence the positioning of the acetabular component at THA. Acetabular component malpositioning errors caused by anterior tilt of the affected hemi pelvis and the abnormal position of the affected side centre of rotation should be considered by orthopaedic surgeons when undertaking THA in patients with Crowe-IV DDH. Cite this article: Bone Joint J 2020;102-B(10):1311–1318

To compare the efficacy of intra-articular and intravenous modes of administration of tranexamic acid in primary total knee arthroplasty in terms of blood loss and fall in haemoglobin level. Study Design: Randomized controlled trial. Duration of Study: Six months, from May 2019 to Nov 2019. Seventy-eight patients were included in the study. All patients undergoing unilateral primary total knee replacement were included in the study. Exclusion criteria were patients with hepatitis B and C, history of previous knee replacement, bilateral total knee replacement, allergy to TXA, Hb less than 11g/dl in males and less than 10g/dl in females, renal dysfunction, use of anticoagulants for 7 days prior to surgery and history of thromboembolic diseases. Patients were randomly divided into group A and B. Group A patients undergoing unilateral primary total knee replacement (TKR) were given intravenous tranexamic acid (TXA) while group B were infiltrated with intra-articular TXA. Volume of drain output, fall in haemoglobin (Hb) level and need for blood transfusion were measured immediately after surgery and at 12 and 24 hours post operatively in both groups. The study included 35 (44.87%) male and 43 (55.13%) female patients. Mean age of patients was 61 ± 6.59 years. The mean drain output calculated immediately after surgery in group A was 45.38 ± 20.75 ml compared with 47.95 ± 23.86 ml in group B (p=0.73). At 24 hours post operatively, mean drain output was 263.21 ± 38.50 ml in intravenous group versus 243.59 ± 70.73 ml in intra-articular group (p=0.46). Regarding fall in Hb level, both groups showed no significant difference (p>0.05). About 12.82% (n=5) patients in group A compared to 10.26% (n=4) patients required blood transfusion post operatively (p=0.72). Intra-articular and intravenous TXA are equally effective in patients undergoing primary total knee arthroplasty in reducing post-operative blood loss

Aims. The glenohumeral joint is the most frequently dislocated articulation, but possibly due to the lower prevalence of posterior shoulder dislocations, approximately 50% to 79% of posterior glenohumeral dislocations are missed at initial presentation. The aim of this study was to systematically evaluate the most recent evidence involving the aetiology of posterior glenohumeral dislocations, as well as the diagnosis and treatment. Materials and Methods. A systematic search was conducted using PubMed (MEDLINE), Web of Science, Embase, and Cochrane (January 1997 to September 2017), with references from articles also evaluated. Studies reporting patients who experienced an acute posterior glenohumeral joint subluxation and/or dislocation, as well as the aetiology of posterior glenohumeral dislocations, were included. Results. A total of 54 studies met the inclusion criteria. In total, 182 patients were included in this analysis; study sizes ranged from one to 66 patients, with a mean age of 44.2 years (. sd. 13.7). There was a higher proportion of male patients. In all, 216 shoulders were included with 148 unilateral injuries and 34 bilateral. Seizures were implicated in 38% of patients (n = 69), with falls, road traffic accidents, electric shock, and iatrogenic reasons also described. Time to diagnosis varied across studies from immediate up to a delay of 25 years. Multiple associated injuries are described. Conclusion. This review provides an up-to-date insight into the aetiology of posterior shoulder dislocations. Our results showed that seizures were most commonly implicated. Overall, reduction was achieved via open means in the majority of shoulders. We also found that delayed diagnosis is common

The aim of this study was to compare the outcome of bilateral sequential total ankle replacement (TAR) with that of unilateral TAR. We reviewed 23 patients who had undergone sequential bilateral TAR under a single anaesthetic and 46 matched patients with a unilateral TAR. There were no significant pre-operative differences between the two groups in terms of age, gender, body mass index, American Society of Anaesthesiologists classification and aetiology of the osteoarthritis of the ankle. Clinical and radiological follow-up was carried out at four months, one and two years. After four months, patients with simultaneous bilateral TAR reported a significantly higher mean pain score than those with a unilateral TAR. The mean American Orthopaedic Foot and Ankle Society hindfoot score and short-form 36 physical component summary score were better in the unilateral group. However, this difference disappeared at the one-and two-year follow-ups. Bilateral sequential TAR under one anaesthetic can be offered to patients with bilateral severe ankle osteoarthritis. However, they should be informed of the long recovery period

We wished to determine whether simultaneous bilateral sequential total knee replacement (TKR) carried increased rates of mortality and complications compared with unilateral TKR in low- and high-risk patients. Our study included 2385 patients who had undergone bilateral sequential TKR under one anaesthetic and 719 who had unilateral TKR. There were no significant pre-operative differences between the groups in terms of age, gender, height, weight, body mass index, diagnosis, comorbidity and duration of follow-up, which was a mean of 10.2 years (5 to 14) in the bilateral and 10.4 years (5 to 14) in the unilateral group. The peri-operative mortality rate (eight patients, 0.3%) of patients who had bilateral sequential TKR was similar to that (five patients, 0.7%) of those undergoing unilateral TKR. In bilateral cases the peri-operative mortality rate (three patients, 0.4%) of patients at high risk was similar to that (five patients, 0.3%) of patients at low risk as it was also in unilateral cases (two patients, 1.0% vs three patients, 0.6%). There was no significant difference (p = 0.735) in either the overall number of major complications between bilateral and unilateral cases or between low- (p = 0.57) and high-risk (p = 0.61) patients. Also, the overall number of minor complications was not significantly different between the bilateral and unilateral group (p = 0.143). Simultaneous bilateral sequential TKR can be offered to patients at low and high risk and has an expected rate of complications similar to that of unilateral TKR

We investigated whether simultaneous bilateral sequential total hip replacement (THR) would increase the rate of mortality and complications compared with unilateral THR in both low- and high-risk groups of patients. We enrolled 978 patients with bilateral and 1666 with unilateral THR in the study. There were no significant pre-operative differences between the groups in regard to age, gender, body mass index, diagnosis, comorbidity as assessed by the grading of the American Society of Anesthesiologists (ASA), the type of prosthesis and the duration of follow-up. The mean follow-up was for 10.5 years (5 to 13) in the bilateral THR group and 9.8 years (5 to 14) in the unilateral group. The peri-operative mortality rate of patients who had simultaneous bilateral THR (0.31%, three of 978 patients) was similar to that of patients with unilateral THR (0.18%, three of 1666 patients). The peri-operative mortality rate of patients in the bilateral group was similar in high risk and low risk patients (0.70%, two of 285 patients vs 0.14%, one of 693 patients) and this was also true in the unilateral THR group (0.40%, two of 500 patients vs 0.09%, one of 1166 patients). Patients with bilateral THR required more blood transfusions and a longer hospital stay than those in the unilateral THR group. There was no significant difference (p = 0.32) in the overall number of complications between the groups. This was also true for the low-risk (p = 0.81) vs high-risk (p = 0.631) patients. Our findings confirm that simultaneous sequential bilateral THR is a safe option for patients who are considered to be either high or low risk according to the ASA classification

Introduction. Most of patients with unilateral hip disease shows muscle volume atrophy of pelvis and thigh in the affected side because of pain and disuse, resulting in reduced muscle weakness and limping. However, it is unclear how the muscle atrophy correlated with muscle strength in the patient with hip disorders. A previous study have demonstrated that the volume of the gluteus medius correlated with the muscle strength by volumetric measurement using 3 dimensional computed tomography (3D-CT) data, however, muscles influence each other during motions and there is no reports focusing on the relationship between some major muscles of pelvis and thigh including gluteus maximus, gluteus medius, iliopsoas and quadriceps and muscle strength in several hip and knee motions. Therefore, the purpose of the present study is to evaluate the relationship between muscle volumetric atrophy of major muscles of pelvis and thigh and muscle strength in flexion, extension and abduction of hip joints and extension of knee joint before surgery in patients with unilateral hip disease. Material and Methods. The subjects were 38 patients with unilateral hip osteoarthritis, who underwent hip joint surgery. They all underwent preoperative computed tomography (CT) for preoperative planning. There were 6 males and 32 females with average age 59.5 years old. Before surgery, isometric muscle strength in hip flexion, hip extension, hip abduction and knee extension were measured using a hand held dynamometer (µTas F-1, ANIMA Japan). Major muscles including gluteus maximus, gluteus medius, iliopsoas and quadriceps were automatically extracted from the preoperative CT using convolutional neural networks (CNN) and were corrected manually by the experienced surgeon. The muscle volumetric atrophy ratio was defined as the ratio of muscle volume of the affected side to that of the unaffected side. The muscle weakness ratio was defined as the ratio of muscle strength of the affected side to that of the unaffected side. The correlation coefficient between the muscle atrophy ratio and the muscle weakness ratio of each muscle were calculated. Results. The average muscle atrophy ratio was 84.5% (63.5%–108.2%) in gluteus maximus, 86.6% (65.5%–112.1%) in gluteus medius, 81.0% (22.1%–130.8%) in psoas major, and 91.0% (63.8%–127.0%) in quadriceps. The average muscle strength ratio was 71.5% (0%–137.5%) in hip flexion, 88.1% (18.8%–169.6%) in hip abduction, 78.6% (21.9%–130.1%) in hip extension and 84.3% (13.1%–122.8%) in knee extension. The correlation coefficient between the muscle atrophy and the ratio of each muscle strength between the affected and unaffected side were shown in Table 1. Conclusion. In conclusion, the muscle atrophy of gluteus medius muscle, psoas major muscle and quadriceps muscle significantly correlated with the muscle weakness in hip flexion. The muscle atrophy of psoas major muscle and quadriceps muscle also significantly correlated with the muscle weakness in knee extension. There were no significant correlation between the muscle atrophy and the muscle weakness in hip extension and abduction

We report a prospective case-series study to evaluate the results of non-operative and operative treatment of symptomatic unilateral lumbar spondylolysis. Non-operative treatment results in healing in most patients with symptomatic unilateral spondylolysis. Surgery however is indicated when symptoms persist beyond a reasonable time affecting the quality of life in young patients particularly the athletic population. We treated 41 patients [31 male, 10 female] with suspected unilateral lumbar spondylolysis. Thirty-one patients were actively involved in sports at various levels. Patients with a positive stress reaction on SPECT imaging underwent a strict protocol of activity restriction, bracing and physical therapy for 6 months. At the end of six months, patients who remained symptomatic underwent a Computed Tomography [CT] scan to confirm the persistence of a spondylolysis. Seven patients subsequently underwent a direct repair of the defect using the modified Buck's Technique. Baseline Oswestry disability index [ODI] and Short-Form-36 [SF-36] scores were compared to two year ODI and SF-36 scores for all patients. In the non-operated group, the mean pre-treatment ODI was 36 [SD=10.5], improving to 6.2 [SD=8.2] at two years. In SF-36 scores, the physical component of health [PCS] improved from 30.7 [SD=3.2] to 53.5 [SD =6.5] [p<0.001], and the mean score for the mental component of health [MCS] improved from 39 [SD=4.1] to56.5 [SD=3.9] [p<0.001] at two years. 20/31 patients resumed their sporting career within 6 months of onset of treatment, a further 4/31 patients returned to sports within one year. The seven patients who remained symptomatic at six months underwent a unilateral modified Buck's Repair. The most common level of repair was L5 (n=4). The mean pre-operative ODI was 39.4 (SD=3.6) improving to 4.4 (SD=4) at the latest follow-up. The mean score of PCS [SF-36] improved from 29.6 [SD=4.4] to 51.2 [SD=5.2] (SD=5.2) (p<0.001) and the mean score of MCS (SF-36) improved from 38.7 (SD=1.9) to 55.5 (SD=5.4) (p<0.001). A specific protocol of conservative treatment for patients with a unilateral lumbar spondylolysis resulted in a high rate of success with 83% of patients avoiding surgery. If symptoms persist beyond a reasonable period (i.e. 6 months) and reverse gantry CT scan confirms a non-healing defect of the pars interarticularis one may consider a unilateral direct repair of the defect with good outcome ultimately

Background. Direct anterior approach (DAA), total hip arthroplasty (THA, performed with the patient in the supine position, creates a unique opportunity to do bilateral THA under one anesthesia. Previous studies evaluating this option are limited by small sample size or lack of control group. The purpose of this study is to compare early clinical outcomes of simultaneous bilateral, unilateral and staged bilateral DAA-THA. Methods. Using an institutional registry database, we reviewed 3977 DAA-THA performed in 3334 patients at minimum 90-days follow up. A single surgeon performed all surgeries. Simultaneous bilateral DAA-THA group included 512 hips in 256 patients, unilateral DAA-THA group 2691 hips and staged bilateral DAA-THA group 774 hips in 387 patients. We reviewed 90-day postoperative complications, readmissions, length of stay, and rate of home discharge between all three groups. Results. There were no statistical differences in readmission (range 0.77–1.8%), postoperative clinical complications, and rate of home discharge (96.1–98.1%) between simultaneous bilateral, unilateral, or staged bilateral groups. The number of transfusions in the simultaneous bilateral group (9/256, 3.5%) was significantly higher than in the unilateral (24/2691, 0.89%, p=0.002) or the staged bilateral group (4/387, 1.0%, p=0.04). The total length of stay (LOS) in the simultaneous bilateral group (1.8 ± 0.8 days) was longer (p<0.001) than in the unilateral group (1.2 ± 1.0 days) but shorter (p<0.001) than the two added LOS in the staged bilateral group (2.8 ± 2.2 days). Conclusion. Our large cohort in a single surgeon case showed that simultaneous bilateral DAA-THA is comparable with unilateral or staged bilateral surgery in regards to postoperative clinical complications, readmission rate, and rate of home discharge but with an increased rate of transfusion. We believe that simultaneous bilateral DAA-THA is a reasonable and safe option in properly selected patients who require bilateral THA

To investigate the clinical results of capsular arthroplasty in the treatment of young patients with unilateral hip dislocation. We retrospectively evaluated all patients who had the capsular arthroplasty from June 2012 to September 2016 in our department. Hips were evaluated using hip Harris score (HHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. The Tonnis osteoarthritis grade and Severin classification were used to access the radiographic outcomes. Fifty-nine patients (10 males and 49 females) with an average of 16.8y (range: 8–26y) were followed by a mean of 32.1 months (range: 12.5–66.0 months). The mean HHS was 83.4 (range: 31.2–99) and WOMAC score was 12.3 (range: 0–49) at the final follow up. Multivariate analysis revealed that the poor capsular quality (OR=8.29) was associated with the poor result. The thicker capsule (OR=0.83) and bigger femoral head (OR=0.73) were associated with the good result. There were 15 patients (25.4%) identified as Tonnis grade 0, 21 patients (35.6%) as grade 1, 18 patients (30.5%) as grade 2 and 5 patients (8.5%) as grade 3. According to Severin classification, 28 patients (47.6%) were regarded as class I, 22 patients (37.3%) as II, 7 patients (11.9%) as III and 2 patients (3.4%) as IV. One patient underwent THA after 41.5 months. The joint stiffness was the most common complication (10.2%). We confirmed the efficacy of the capsular arthroplasty in the treatment of young patients with unilateral hip dislocation. The capsular quality and the size of femoral head were associated with the clinical results

Five vertebrae with unilateral spondylolysis are presented. The associated asymmetry of the posterior elements supports the concept of a localised form of growth deficiency. The defect is difficult to demonstrate radiologically, and is perhaps present more frequently than is recognised. It should be suspected clinically from asymmetry of the neural arch and from unilateral wedging of the vertebral body, and may be demonstrated by further radiographic examination. The clinical significance is uncertain, but one patient is presented in whom unilateral spondylolysis was associated with intermittent sciatic pain

Hip resurfacing arthroplasty (HRA) became a popular procedure in the early 90s because of the improved wear characteristic, preserving nature of the procedure and the optimal stability and range of motion. Concerns raised since 2004 when metal ions were seen in blood and urine of patients with a MoM implant. Design of the prosthesis, acetabular component malpositioning, contact-patch-to-rim distance (CPR) and a reduced joint size all seem to play a role in elevated metal ion concentrations. Little is known about the influence of physical activity (PA) on metal ion concentrations. Implant wear is thought to be a function of use and thus of patient activity levels. Wear of polyethylene acetabular bearings was positively correlated with patient's activity in previous studies. It is hypothesized that daily habitual physical activity of patients with a unilateral resurfacing prosthesis, measured by an activity monitor, is associated with habitual physical activity. A prospective, explorative study was conducted. Only patients with a unilateral hip resurfacing prosthesis and a follow-up of 10 ± 1 years were included. Metal ion concentrations were determined using ICP-MS. Habitual physical activity of subjects was measured in daily living using an acceleration-based activity monitor. Outcome consisted of quantitative and qualitative activity parameters. In total, 16 patients were included. 12 males (75%) and 4 females (25%) with a median age at surgery of 55.5 ± 9.7 years [43.0 – 67.9] and median follow-up of 9.9 ± 1.0 years [9.1 – 10.9]. The median cobalt and chromium ion concentrations were 25 ± 13 and 38 ± 28 nmol/L. A significant relationship, when adjusting for age at surgery, BMI, cup size and cup inclination, between sit-stand transfers (p = .034) and high intensity peaks (p = .001) with cobalt ion concentrations were found (linear regression analysis). This study showed that a high number of sit-stand transfers and a high number of high intensity peaks is significantly correlated with high metal ion concentrations, but results should be interpreted with care. For patients it seems save to engage in activities with low intensity peaks like walking or cycling without triggering critical wear or metal ions being able to achieve important general health benefits and quality of life, although the quality (high intensity peaks) of physical activity and behaviour of patients (sit-stand-transfers) seem to influence metal ion concentrations

Traumatic unilateral facet dislocation of the lumbosacral junction without fracture or with non-displaced fractures of adjacent vertebrae is extremely rare. We describe a case of a young male who sustained a unilateral facet dislocation of the lumbosacral junction in a motor vehicle accident. The unusual features of this case include an unremarkable physical and neurological examination on presentation and absence of other substantial vertebral or extra-vertebral injuries

Aims. The aim of this study was to compare the cost-effectiveness of treatment with an osseointegrated percutaneous (OI-) prosthesis and a socket-suspended (S-) prosthesis for patients with a transfemoral amputation. Patients and Methods. A Markov model was developed to estimate the medical costs and changes in quality-adjusted life-years (QALYs) attributable to treatment of unilateral transfemoral amputation over a projected period of 20 years from a healthcare perspective. Data were collected alongside a prospective clinical study of 51 patients followed for two years. Results. OI-prostheses had an incremental cost per QALY gained of €83 374 compared with S-prostheses. The clinical improvement seen with OI-prostheses was reflected in QALYs gained. Results were most sensitive to the utility value for both treatment arms. The impact of an annual decline in utility values of 1%, 2%, and 3%, for patients with S-prostheses resulted in a cost per QALY gained of €37 020, €24 662, and €18 952, respectively, over 20 years. Conclusion. From a healthcare perspective, treatment with an OI-prosthesis results in improved quality of life at a relatively high cost compared with that for S-prosthesis. When patients treated with S-prostheses had a decline in quality of life over time, the cost per QALY gained by OI-prosthesis treatment was considerably reduced. Cite this article: Bone Joint J 2018;100-B:527–34

Methods. A retrospective review of 80 patients with unilateral slipped capital femoral epiphysis from 1998–2012 was undertaken to determine the outcome of the unaffected hip. All patients were treated with either prophylactic single Richards screw fixation or observation of the uninvolved hip and were followed up for at least 12 months. The unaffected hip of 44 patients (mean age 12.6 years, range 9–17) had simultaneous prophylactic fixation and 36 patients (mean age 13.4 years, range 9–17.4) were managed with observation. Results. Sequential slip of the unaffected hip was noted in 10 patients (28 per cent) in the observation group and only in 1 patient (2 per cent) in the group managed with prophylactic fixation. A Fisher's exact test showed significantly high incidence of sequential slip in unaffected hips when managed with regular observation (p-value 0.002). Only 3 cases had symptomatic hardware on the unaffected side after prophylactic fixation with one requiring revision of the metal work; one had superficial wound infection treated with antibiotics. No cases had AVN or chondrolysis. Conclusion. Simultaneous prophylactic fixation of the unaffected hip significantly reduces the incidence of sequential slip in unilateral SCFE with minimal complications. Level of evidence. III

Between 1992 and 1997, we undertook a prospective, targeted clinical and ultrasonographic hip screening programme to assess the relationship between ultrasonographic abnormalities of the hip and clinical limitation of hip abduction. A total of 5.9% (2 of 34) of neonatal dislocatable hips and 87.5% (7 of 8) of ‘late’ dislocated hips seen after the age of six months, presented with unilateral limitation of hip abduction. All major (Graf type III) and 44.5% of minor (Graf type II) dysplastic hips presented with this sign. Statistically, bilateral limitation of hip abduction was not a useful clinical indicator of underlying hip abnormality because of its poor sensitivity, but unilateral limitation of abduction of the hip was a highly specific (90%) and reasonably sensitive sign (70%). It was more sensitive than the neonatal Ortolani manoeuvre, which has been considered to be the method of choice. It was, however, not sensitive enough to be of value as a routine screening test in developmental dysplasia of the hip. We consider unilateral limitation of hip abduction to be an important clinical sign and its presence in an infant over the age of three to four months makes further investigation essential

Posterior cruciate ligament deficiency (PCLD) leads to structural and proprioceptive impairments of the knee, affecting the performance of daily activities including obstacle-crossing. Therefore, identifying the biomechanical deficits and/or strategies during this motor task would be helpful for rehabilitative and clinical management of such patients. A safe and successful obstacle-crossing requires stability of the body and sufficient foot clearance of the swing limb. Patients with PCLD may face demands different from normal when negotiating obstacles of different heights. The objective of this study was thus to identify the biomechanical deviations/strategies of the lower limbs in unilateral PCLD during obstacle-crossing using motion analysis techniques. Twelve patients with unilateral PCLD and twelve healthy controls participated in the current study with informed written consent. They were asked to walk and cross obstacles of heights of 10%, 20% and 30% of their leg lengths at self-selected speeds. The PCLD group was asked to cross the obstacles with each of the affected and unaffected limb as the leading limb, denoted as PCLD-A and PCLD-U, respectively. The kinematic and kinetic data were measured with a 7-camera motion analysis system (Vicon, Oxford Metrics, U.K.) and two force plates (AMTI, U.S.A.). The angles of the stance and swing limbs (crossing angles) and the moments of the stance limbs (crossing moments) for each joint in the sagittal plane when the leading limb was above the obstacle were calculated for statistical analysis. A 3 by 2, 2-way mixed-model analysis of variance with one between-subject factor (PCLD-A vs. Control, and PCLD-U vs. Control) and one within-subject factor (obstacle height) was performed (α=0.05). Paired t-test was used to compare the variables between PCLD-A and PCLD-U (α=0.05). SAS version 9.2 was used for all statistical analysis. When the leading toe was above the obstacle, the PCLD group showed significantly greater hip flexion in the swing limb but decreased dorsiflexion in the stance limb, both in PCLD-A and PCLD-U (P<0.05). Greater knee flexion and greater ankle dorsiflexion were found in the leading limb in PCLD-A (P<0.05). Meanwhile, the PCLD group showed significantly decreased ankle plantarflexor but increased knee extensor crossing moments in the stance limb compared with the Control (P<0.05). None of the calculated variables were found to be significantly different between PCLD-A and PCLD-U (P>0.05). When crossing the obstacle, patients with PCLD reduced ankle plantarflexor moments that were mainly produced by the gastrocnemius. This may help reduce the posterior instability of the affected knee. Greater knee extensor crossing moments may also help reduce the posterior instability of the standing knee when the leading toe was above the obstacle. The changed joint kinetics as a result of PCLD were not only seen on the affected side but also on the unaffected side during obstacle-crossing. This symmetrical pattern may be necessary in performing functional activities that may require either the affected side or the unaffected side leading. These results suggest that rehabilitative intervention, including muscular strengthening, on both affected and unaffected sides are necessary in patients with unilateral PCLD

Introduction. Limb length discrepancy (LLD) is one of the major reasons of dissatisfaction after total hip arthroplasty(THR) and limb equalization after THR in unilateral developmental dysplasia of the hip (DDH) is very important. study designed to measure the difference of adult femoral length between normal and dislocated hip in unilateral DDH. Method. Sixty patients with unilateral high riding DDH (crow type 3,4) who were underwent THR included. All the cases had digital lower limb scanograms. Exclusion criteria was any previous hip or femur surgery, any rheumatoid disease, history of any disease that affect the growth. All the scanograms measured by one fellowship of adult reconstruction and one radiologist specialized in musculoskeletal imaging. Each one repeated the measurements two months later blindly and inter observer and intra observer reliability checked. Each one measured femoral length in both sides from greater trochanter(GT), to the distal surface of the femoral condyles. Results. 59 female and one males included. Average age was 27.5 years (19–50 years). Inter observer reliability index were excellent (ICC 98%). Only 6 cases (10%) had exactly equal femoral length, 31(52%) cases were longer on the dislocated side and 23 (38%) cases were shorter. Average overgrowth was 6.1 mm (Range: 1–22) and average undergrowth was 10.7 (Range 1–21). 35 cases (58.3%) cases had 5 mm or more differences and 30% had 5–10 mm .17 cases (28.3%) had at least 10 mm difference that 8 cases (13%) had shorter and 9 cases (15%) had longer femur on dislocated side. Maximum difference was 22 mm over length on dislocated side. Conclusions. More than half of patients with unilateral high riding DDH have longer femur on the dislocated side and 15% of them are longer than 10 mm. we recommend to get the scanograms in all the unilateral DDH cases to avoid post-operative limb discrepancy and detecting the amount of shortening in cases that need femoral shortening

Background. Active therapeutic exercises during unstable and unilateral conditions using body weight for resistance are often used in the rehabilitation of low back pain (LBP). In LBP patient's unilateral atrophy of the spinal muscles is reported. To address these deficits understanding side to side muscle activity using surface Electromyography (SEMG) can help clinicians design exercises that specifically address these deficits. Aim: To identify the effects of unilateral and unstable bridging exercises on trunk muscle activity. Methods. Using a repeated measures design, SEMG side to side measurements of lumbar Multifidus (MF), Iliocostalis Thoracis (ICT), Rectus Abdominis (RA) and External Oblique (EO) were conducted on 20 healthy subjects (16 female, age 25.45±3.57 years, height 166±0.8 cm, weight 63.35±12.70 kg. Mean Body Mass Index 23) during 8 supine bridging exercises with stable, unstable and unilateral conditions. Results. Muscle activity was significantly influenced by unilateral and unstable conditions. Highest SEMG activity was found in MF and ICT, lowest in RA and EO in all exercises. Highest SEMG activity of all investigated muscles was found during all unstable or unilateral conditions and lowest activity during standard bridging exercises. Unilateral exercises increased ipsilateral EMG activity on the unsupported side of all investigated muscles. Conclusion. The results suggest that unilateral atrophied muscles can be specifically trained by using unilateral bridging exercises. The intensity of the exercises can be adapted to subjects' ability by including various unstable or unilateral conditions within the bridging exercise, since individual muscle activity ranges from low to high activity between the exercises. Conflicts of Interest. None. Source of Funding. None. I confirm that this abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting

With the increase in the elderly population, there is a dramatic increase in the number of spinal fusions. Spinal fusion is usually performed in cases of primary instability. However it is also performed to prevent iatrogenic instability created during surgical treatment of spinal stenosis in most cases. In literature, up to 75% of adjacent segment disease (ASD) can be seen according to the follow-up time. 1. Although ASD manifests itself with pathologies such as instability, foraminal stenosis, disc herniation or central stenosis. 1,2. There are several reports in the literature regarding lumbar percutaneous transforaminal endoscopic interventions for lumbar foraminal stenosis or disc herniations. However, to the best our knowledge, there is no report about the treatment of central stenosis in ASD. In this study, we aimed to investigate the short-term results of unilateral biportal endoscopic decompressive laminotomy (UBEDL) technique in ASD cases with symptomatic central or lateral recess stenosis. The number of patients participating in the prospective study was 8. The mean follow-up was 6.9 (ranged 6 to 11) months. The mean age of the patients was 68 (5m, 3F). The development of ASD time after fusion was 30.6 months(ranged 19 to 42). Mean fused segments were 3 (ranged 2 to 8). Preoperative instability was present in 2 of the patients which was proven by dynamic lumbar x-rays. Preoperative mean VAS-back score was 7.8, VAS Leg score was 5.6. The preoperative mean JOA (Japanese Orthopaedic Association) score was 11.25. At 6th month follow-up, the mean VAS back score of the patients was 1, and the VAS leg score was 0.5. This improvement was statistically significant (p = 0.11 and 0.016, respectively). The mean JOA score at the 6th month was 22.6 and it was also statistically significant comparing preoperative JOA score(p = 0.011). The preoperative mean dural sac area measured in MR was 0.50 cm2, and it was measured as 2.1 cm. 2. at po 6 months.(p = 0.012). There was no progress in any patient's instability during follow-up. In orthopedic surgery, when implant related problems develop in any region of body (pseudoarthrosis, infection, adjacent fracture, etc.), it is generally treated by using more implants in its final operation. This approach is also widely used in spinal surgery. 3. However, it carries more risk in terms of devoloping ASD, infection or another complications. In the literature, endoscopic procedures have almost always been used in the treatment of ventral pathologies which constitute only 10%. In ASD, disease devolops as characterized by wide facet joint arthrosis and hypertrophied ligamentum flavum in the cranial segment and it is mostly presented both lateral recess and santal stenosis symptoms (39%). In this study, we found that UBEDL provides successful results in the treatment of patients without no more muscle and ligament damage in ASD cases with spinal stenosis. One of the most important advantages of UBE is its ability to access both ventral and dorsal pathologies by minimally invasive endoscopic aproach. I think endoscopic decompression also plays an important role in the absence of additional instability at postoperatively in patients. UBE which has already been described in the literature given successful results in most of the spinal degenerative diseases besides it can also be used in the treatment of ASD. Studies with longer follow-up and higher patient numbers will provide more accurate results

Europeam Group of Neuro-orthopaedic (GLAENeO), Caracas, The prevention of a dislocated hip is one of the aims of early surgery in Cerebral Palsy children, specially those severely involved. We performed a retrospective study of those cerebral palsy patients operated of adductor tenotomy between 1975 and 1995 with a total of 1474 patients. We grouped them in those who had a unilateral tenotomy and those who had a bilateral tenotomy as primary surgery. Of these only 8% had an obturator neurectomy, without walking ability, and 92 % had it not. Age at surgery varied from 6 months to 8 years of age with a mean of 4 years and 3 months. Group I: 792 patients (53.7 %) with unilateral adductor contracture, sustained a unilateral adductor tenotomy. Of these patients a total of 619 (78, 2 %) required a contralateral adductor tenotomy at a mean of 3 years and 6 months. Group II: 682 patients (46, 3 %) with bilateral adductor contracture that had a bilateral adductor tenotomy in one stage. Of the 792 patients that sustained a two stage adductor tenotomy, 123 (20%) presented a unilateral dislocated hip and of these 115 (93 %) occurred in the hip operated secondly at a mean of 1 year post tenotomy. Of the 682 patients with bilateral adductor tenotomies only 7 (1 %) had a dislocated hip 2 years post tenotomy. Of the 72 dislocated hips, 12 (59 %) were quadriplegics, 28 (22 %) were diplegic, 21 (18 %) hemiplegics and 1 (1 %) tetraplegic. Of the 619 patients tenotomized in two stages, in 143 the diaphyseal – cervical angle was 155 ° (23,1 %), at a mean of 6 and a half years of age and 3 years post the second tenotomy. In 102 of these patients (71 %) a varus derotation osteotomy was performed in the hip operated in the second act with further dislocation of the hip in 20 cases (20 %). Of the 685 patients with bilateral tenotomy in one stage, varus derotation osteotomy was required in 68 (68 %) at a mean of 6 years of age with only a 3 % of dislocations in this group. In view of these results we recommend a bilateral adductor tenotomy be performd regardless of a difference in the degree of contracture of both sides, thus coordinating the forces and avoid further dislocation the hip

Introduction The decision to perform bilateral total knee replacement (TKR) either simultaneously or as a staged procedure is made depending on the level of disease severity, comorbidities, total anaesthetic time and cost. We compared the outcomes of these two bilateral groups of patients with unilateral TKR. Methods Between August 1992 and December 2002 all patients requiring primary TKR received an uncemented, hydroxyapatite-coated, posterior cruciate ligament retaining prosthesis implanted by the senior author. All peri-operative complications were recorded prospectively, as were pre-operative and post-operative knee scores (Knee Society Clinical Rating Score) at three and six months, and one, two, five, and 10 years thereafter. Patients were divided into three groups being; simultaneous bilateral TKR (SIM), staged bilateral TKR (STA), and unilateral TKR (SIN) with the outcomes of each group compared for statistical significance. One thousand one hundred and forty patients (1638 knees) were included in the study. The majority of patients were female in the STA and SIN groups (60% and 53% respectively) and males in the SIM group (57%). There were 790 (SIM), 206 (STA), and 642 (SIN) knees with mean ages of 67 (SIM), 65 (STA), and 67 years (SIN). The primary diagnosis was OA in each of the groups (> 93%). Results Pre-operative and post-operative scores revealed no significant differences (p> .05) between the groups. Mean scores ranged from 94 to 98 pre-operatively and increased up to 182 to 187 at five years. Post-operative complications were significantly higher (p< .01) in both bilateral groups. There were 68 (17.2%) and 16 (15.5%) cases of thrombi in the SIM and STA groups respectively compared to 60 (9.3%) cases in the SIN group. Pulmonary emboli were also significantly higher in the bilateral groups compared to the unilateral group (p< .01). The rate of deep infection was higher (p=.09) in the STA group compared to the SIM and SIN groups (2.9% of patients compared to 1.1% and 1.4% respectively). There have been 10 revisions (four SIM, one STA, and five SIN) and two cases of peri-operative death (one STA, one SIM) both due to MI. Conclusions While simultaneous TKR has higher rates of post-operative complication compared to unilateral TKR, it is less than staged TKR. Therefore simultaneous bilateral knee replacements, when indicated, are the ideal treatment of choice compared to staged procedures

To compare the efficacy of intra-articular and intravenous modes of administration of tranexamic acid in primary Total Knee Arthroplasty in terms of blood loss and fall in haemoglobin level. This randomized controlled trial was conducted from 12th May 2017 to 11th May 2017. Seventy eight patients were included in the study. Patients were randomly divided into group A and B. Group A patients undergoing unilateral primary total knee replacement (TKR) were given intravenous tranexamic acid (TXA) while group B were infiltrated with intra-articular TXA. Volume of drain output, fall in haemoglobin (Hb) level and need for blood transfusion were measured immediately after surgery and at 12 and 24 hours post operatively in both groups. The study included 35 (44.87%) male and 43 (55.13%) female patients. Mean age of patients was 61±6.59 years. The mean drain output calculated immediately after surgery in group A was 45.38±20.75 mL compared with 47.95±23.86 mL in group B (p=0.73). 24 hours post operatively, mean drain output was 263.21±38.50 mL in intravenous group versus 243.59±70.73 mL in intra-articular group (p=0.46). Regarding fall in Hb level, both groups showed no significant difference (p>0.05). 12.82% (n=5) patients in group A compared to 10.26% (n=4) patients required blood transfusion post operatively (p=0.72). Intra-articular and intravenous TXA are equally effective in patients undergoing primary total knee arthroplasty in reducing post operative blood loss. For any reader queries, please contact . drjunaidrmc@gmail.com

We reviewed 16 patients with spina bifida and unilateral dislocation of the hip at an average age of 17 years. Nine had a high neurological level (thoracic to L3) and seven a low lesion (L4 to sacral). We assessed the influence of unilateral dislocation of the hip on leg-length discrepancy, hip pain, hip stiffness and pressure sores of the ischial tuberosity. In non-walking patients with high-level lesions, unilateral dislocation gave little functional disability and did not appear to require reduction. In walking patients with low-level lesions, leg-length discrepancy led to a poor gait and functional problems which could be prevented by reduction of the dislocation. In all patients with low lesions, surgery was successful in maintaining reduction; in two of five patients with high lesions it was unsuccessful

Objectives. External fixators are the traditional fixation method of choice for contaminated open fractures. However, patient acceptance is low due to the high profile and therefore physical burden of the constructs. An externalised locking compression plate is a low profile alternative. However, the biomechanical differences have not been assessed. The objective of this study was to evaluate the axial and torsional stiffness of the externalised titanium locking compression plate (ET-LCP), the externalised stainless steel locking compression plate (ESS-LCP) and the unilateral external fixator (UEF). Methods. A fracture gap model was created to simulate comminuted mid-shaft tibia fractures using synthetic composite bones. Fifteen constructs were stabilised with ET-LCP, ESS-LCP or UEF (five constructs each). The constructs were loaded under both axial and torsional directions to determine construct stiffness. Results. The mean axial stiffness was very similar for UEF (528 N/mm) and ESS-LCP (525 N/mm), while it was slightly lower for ET-LCP (469 N/mm). One-way analysis of variance (ANOVA) testing in all three groups demonstrated no significant difference (F(2,12) = 2.057, p = 0.171). There was a significant difference in mean torsional stiffness between the UEF (0.512 Nm/degree), the ESS-LCP (0.686 Nm/degree) and the ET-LCP (0.639 Nm/degree), as determined by one-way ANOVA (F(2,12) = 6.204, p = 0.014). A Tukey post hoc test revealed that the torsional stiffness of the ESS-LCP was statistically higher than that of the UEF by 0.174 Nm/degree (p = 0.013). No catastrophic failures were observed. Conclusion. Using the LCP as an external fixator may provide a viable and attractive alternative to the traditional UEF as its lower profile makes it more acceptable to patients, while not compromising on axial and torsional stiffness. Cite this article: B. F. H. Ang, J. Y. Chen, A. K. S. Yew, S. K. Chua, S. M. Chou, S. L. Chia, J. S. B. Koh, T. S. Howe. Externalised locking compression plate as an alternative to the unilateral external fixator: a biomechanical comparative study of axial and torsional stiffness. Bone Joint Res 2017;6:216–223. DOI: 10.1302/2046-3758.64.2000470

Aims: Cobalt (Co) and chromium (Cr) ion associated carcinogenesis and chromosomal damage in animals have raised concerns that metal-on-metal (MOM) total hip replacement (THR) in humans may produce the same effects over time. Considering that the risks may be related to the level of these ions in the body, this study compared the serum Co and Cr levels in patients with unilateral versus bilateral 28 mm diameter MOM THR. Methods: All patients having THR at our institution were prospectively registered on a computerised database. From our database, 108 Ultima MOM THR with 28 mm CoCrMo bearing were identified. After patient review in clinic and before blood results were known, patient matching was performed by date after surgery, activity level and weight. Using these stringent criteria, 11 unilateral THR could be adequately matched with 11 bilateral THR. Blood serum was taken with full anti-contamination protocols and serum analysed via inductively coupled plasma mass spectrometry (ICP-MS) Statistical analysis used the Mann-Whitney U test. Results: The median serum Co level after unilateral MOM THR was 22 nmol (range 15 to 37 nmol) compared to 42 nmol (range 19 to 221 nmol) for bilateral MOM THR (p=0.001). The median serum Cr level after unilateral MOM THR was 19 nmol (range 2 to 35 nmol) compared to 52 nmol (range 19 to 287 nmol) for bilateral MOM THR (p=0.04). Conclusions: This study has shown that the serum Co and Cr levels in patients with bilateral MOM THR are significantly higher than those with unilateral MOM THR. With levels of up to 50 times the upper of limit of normal, this finding may be of relevance for the development of potential long-term side effects

Aims: Elevated serum cobalt and chromium ion levels associated with carcinogenesis and chromosomal damage in animals has raised concerns that metal-on-metal (MOM) total hip replacement (THR) in humans may produce the same effects over time. Considering that the risks may be related to the level of these ions in the body, this study compared the serum cobalt and chromium ion levels in patients with unilateral versus bilateral 28 mm diameter MOM THR. Methods: All patients having THR at our institution were prospectively registered on a computerised database. From our database, we identified 108 patients with Ultima (Johnson and Johnson, Leeds) MOM THR with 28 mm bearing made of cobalt-chromium alloy. After patient review in clinic and before blood results were known, patient matching was performed by date after surgery at blood sampling, activity level and body mass. Using these stringent criteria, 11 unilateral THR could be adequately matched with 11 bilateral THR. Blood serum was taken with full anti-contamination protocols and serum analysed via inductively coupled plasma mass spectrometry. Statistical analysis used the Mann-Whitney U test. Results: The serum cobalt ion level after unilateral MOM THR was 4.4 times normal (median 22 nmol/L, range 15 to 37 nmol/L) compared to 8.4 times normal (median 42 nmol/L, range 19 to 221 nmol/L) for bilateral MOM THR (p=0.001). The serum chromium ion level after unilateral MOM THR was 3.8 times normal (median 19 nmol/L, range 2 to 35 nmol/L) compared to 10.4 times normal (median 52 nmol/L, range 19 to 287 nmol/L) for bilateral MOM THR (p=0.04). Conclusions: This study has shown that the serum cobalt and chromium ion levels in patients with bilateral MOM THR are significantly higher than those in patients with unilateral MOM THR. With levels of up to 50 times the upper limit of normal, this finding may be of relevance for the potential development of long-term side effects

We treated 36 patients with unilateral facet dislocations or fracture-dislocations of the cervical spine at the Mayo Clinic between 1975 and 1986. Adequate records were available for 34: ten patients were treated by open reduction and posterior fusion, and 24 by nonoperative management. Of these, 19 had halo traction followed by halo-thoracic immobilisation, four had a simple cervicothoracic orthosis, and one received no active treatment. Anatomical reduction was achieved more frequently in the operative group (60% compared with 25%). Nonoperative treatment was more likely to result in cervical translation on flexion/extension lateral radiographs, and in significant symptoms. Only 36% of the patients treated by halo traction achieved anatomical alignment; in 25% halo traction failed to achieve or maintain any degree of reduction. During halo-thoracic immobilisation, half of the patients lost some degree of reduction and patient satisfaction with the appliance was low. Open reduction and internal fixation of unilateral facet injuries gave better results. 6

The number of hip arthroplasty procedures has steadily increased in the United States over the last decade [Wolford, et. al, 2015]. This trend will continue as this treatment is the most effective approach in relieving pain, improving mobility, reducing fall risk and improving the quality of life in patients with end-stage osteoarthritis. The effectiveness of recovery can be impacted by factors such as access to postoperative physical therapy regimens. During the recovery period, it is important for therapists to be guided in their therapeutic decision making by accurate data concerning the patient's performance on a variety of measures. This project is designed to map the gait recovery curves of individuals who have undergone unilateral hip arthroplasty. To date, eight individuals (4 females, mean age 64.9, SD 11.1) have participated in the study. Five of the patients were treated by traditional press-fit Accolade II implants (Stryker, Mahwah, NJ USA) through a direct anterior approach THA and the other three has been treated by using DAA THA and using neck preserving Minihip. TM. short stem implant (Corin Ltd., Cirencester, UK). Each participant walked on an instrumented treadmill as a self-selected speed for three minutes pre-surgery. Post-surgery data collections occurred at three and six weeks, and three and six months and employed the same treadmill speed as used prior to surgery. Bilateral lower limb kinematic data was collected with a 12 camera motion capture system Vicon® (Oxford Metrics, Oxford, UK) using reflective markers attached to the hip, knee, ankle, heel and toe. Force plates embedded in the treadmill provided kinetic data that aided in the detection of heel strike and toe off. The temporal features associated with gait, including stride, stance time and double support time were obtained for both the surgical and non-surgical limbs and were used to assess changes in performance during the recovery period. The stance and double support data were also converted to a percentage of stance values which provide additional insights into gait control strategies. Repeated measure MANOVAs were used to evaluate any potential differences in the variables either between limbs or over time. Results from the statistical testing revealed that there were no significant differences between the two limbs for either stride or stance time. This was expected since global asymmetrical gait would have led to the participants veer off of the treadmill. There was a main effect of ‘Time’ for both stride and stance times. Post hoc testing indicated that the 6-month post-surgery measures were significantly reduced when compared to the Pre-surgery and 3-week post-surgery measures. Similarly, there were no significant differences in double support times between the two legs but there was a main effect for time. Post hoc testing revealed that the 6-month post-surgery double support time was significantly less than the Pre-surgery and 3-week post-surgery measures. These significant changes clearly indicate that surgery is effective in improving gait parameters. Moreover, clinicians may want to consider assessing double support time as this measure is a particularly robust indicator of the effectiveness of unilateral hip arthroplasty

Purpose: Metal-on-metal (MOM) bearing surfaces release ions locally and into the systemic circulation. This elevation raises concern about the long term effects of elevated metal ions. The goal of the present study was to monitor serum cobalt (Co) and chromium (Cr) levels in patients after MOM resurfacing hip arthroplasty with the Cormet 2000 prosthesis. We present here pilot data on Co and Cr levels in patients with bilateral versus unilateral hip resurfacing devices. Method: We prospectively collected patient characteristics, outcome, and serum samples from device implanted subjects at 6 months, 1, 2, and 3 years following surgery. Unilateral patients had one implant during the entire course of follow-up and bilateral patients were included after the second implant surgery was performed. Serum Co/Cr levels were determined using high-resolution inductively coupled plasma mass spectrometry. Students t-test was used to compare ion levels in two groups based on the number of resurfacing implants (bilateral versus unilateral). Results: 41 unilateral and 9 bilateral subjects were enrolled and followed for serum Co and Cr levels. In general, Co/Cr levels were increased at all time points when compared to control levels in both groups. Bilateral subjects had average serum levels concentrations significantly higher than those observed for unilateral cases (Co: 5.99 vs 2.56 μg/L (p=0.0001); Cr: 6.66 vs 3.60 (p=0.0009). Conclusion: Elevated serum Co/Cr levels were observed at all time points following implantation in both groups and serum levels were nearly 2 times higher in the bilateral group. Based on these preliminary findings, patients undergoing bilateral total hip resurfacing arthroplasty may need to be monitored more closely than those patients receiving unilateral devices. In addition, these bilateral cases may be at a greater risk of ion level toxicities than the unilateral population

Introduction. In cases of unilateral clubfoot, the leg and foot is visually smaller than the opposite, uninvolved side. Parents want to know how much smaller the leg and foot will be. The purpose of this study was to answer this question and compare the results of children treated with a posterior medial release (PMR) with those treated with the Ponseti method (PM). Methods. This is a prospective, longitudinal study of calf circumference and foot length. We measured the calf circumference with a tape measure at the visually maximum girth of the uninvolved side and at the symmetrical position of the involved side. We measured each foot length from the tip of the hallux to the end of the heel. We recorded the measurements at each follow-up visit in a database and analysed the data using linear regression analysis. Results. We followed 93 children (65 PMR, 28 PM) for a mean of 68 months (SD 55, range 6-252) The ratio men/women was 53/40. Mean percent calf size difference was 9.83% (95%CL 8.74-10.92%). Mean percent foot size difference was 8.70% (95%CL 7.54-9.87%). From the numbers available, no differences between the two procedures are evident. Conclusion. Children with a unilateral clubfoot have c10% smaller calf circumference and foot length as compared to the uninvolved side. We found no differences between children treated with PMR or PM, implying the smaller size is intrinsic to the condition and not due to type of treatment

Aims: Cobalt (Co) and chromium (Cr) ion associated carcinogenesis and chromosomal damage in animals has raised concerns that metal-on-metal (MOM) total hip replacement (THR) in humans may produce the same effects over time. Considering that the risks may be related to the level of these ions in the body, this study compared the serum Co and Cr levels in patients with unilateral versus bilateral 28 mm diameter MOM THR. Methods: All patients having THR at our institution were prospectively registered on a computerised database. From our database, 108 Ultima MOM THR with 28 mm CoCrMo bearing were identiþed. After patient review in clinic and before blood results were known, patient matching was performed by date after surgery, activity level and weight. Using these stringent criteria, 11 unilateral THR could be adequately matched with 11 bilateral THR. Blood serum was taken with full anti-contamination protocols and serum analysed via atomic absorption spectrometry. Statistical analysis used the Mann-Whitney U test. Results: The median serum Co level after unilateral MOM THR was 22 nmol (range 15 to 37 nmol) compared to 42 nmol (range 19 to 221 nmol) for bilateral MOM THR (p=0.001). The median serum Cr level after unilateral MOM THR was 19 nmol (range 2 to 35 nmol) compared to 52 nmol (range 19 to 287 nmol) for bilateral MOM THR (p=0.04). Conclusions: This study has shown that the serum Co and Cr levels in patients with bilateral MOM THR are signiþcantly higher than those with unilateral MOM THR. With levels of up to 50 times the upper limit of normal, this þnding may be of relevance for the potential development of long-term side effects

Introduction:. The clinical significance of serum metal ion levels alone in patients with stemmed MoM hip arthroplasty remains uncertain. This study aims to measure the metal ion levels in patients with unilateral and bilateral hip arthroplasty to see whether or not the patients with bilateral hips have higher metal ions. Patients and Methods. All the patients with bilateral MoM hip arthroplasty were identified from the research database. These patients were then matched with those in a similar age group who had a unilateral hip arthroplasty, but same University of California Los Angeles (UCLA) activity score. The UCLA activity scores along with other hip scores have been previously gathered for all the patients. Both sets of patients then had measurement of serum cobalt and chromium levels. The results were analyzed and compared. Results:. There were a total of 53 patients with bilateral hips and 53 matched patients with unilateral hips. The average serum Cobalt and Chromium levels were 34 nmol/L (range <10–76) and 23 nmol/L (range <10–104) respectively in the bilateral group; and 14 nmol/L (range <10–45) and 21 nmol/L (range <10–57) in the unilateral group. Given that the MHRA (UK) threshold levels deemed clinically significant are 120 nmol/L and 135 nmol/L for Cobalt and Chromium respectively; the results obtained here are not clinically significant. Conclusions:. One would normally expect, with mathematical reasoning, a patient with bilateral hip arthroplasty to have higher serum metal ion levels than a patient with unilateral arthroplasty. However, this study goes to show that it is not the case

Ring frames have the advantage of allowing progressive correction. However, the available frames for complex deformities are heavy and bulky leading to poor compliance by patients. Also, the mounting procedure requires considerable expertise and skill. On the other hand, a unilateral external fixator has the advantages of less bulk and a lighter weight. Thus, it causes less disability and can achieve better patient compliance even with bilateral application. However, previous unilateral fixators have had various limitations with respect to deformity correction, such as restricted placement of hinges, restricted correction planes, and a limited range of correction angles. In addition, it was impossible to achieve progressive correction while fixation was maintained. To overcome these disadvantages of existing unilateral fixators, we developed a new fixator for gradual correction of multi-plane deformities including translational and rotation deformities. This unilateral external fixator is equipped with a universal bar link system. The link is constructed from three dials and two splines that are connecting the dials. The pin clamps are able to vary the direction of a pin cluster in the three dimensional planes. The system allows us to correct angulation, translation, rotation, and the combination of the above. In addition, open or closed hinge technique is available because the correction hinge can be placed right on the center of rotational angulation (CORA), or at any desired location, by adjusting the length of the link spline. By increasing the spline length, the virtual hinge can also be set far from the fixator. Gradual correction can be performed by rotating the three dials using a worm gear goniometer that is temporarily attached. A 3D reconstructed image of the bone is generated preoperatively. Preoperative planning can be done using this image. Mounting parameters are determined by postoperative AP and lateral computed radiography images. These postoperative images are matched with the pre-operative 3D CT image by 2D and 3D image registration. Then, the fixator can be virtually fixed to the bone. By performing virtual correction, it is possible to plan the correction procedure. The fixator is manipulated by rotating each of the three dials to the predetermined angles calculated by the software. Static load testing disclosed that the fixator could bear a load of 1700 N. No breakage or deformation of the fixator itself was recognized. Mechanical testing demonstrated that this new fixator has sufficient strength for full weight bearing, as well as sufficient fatigue resistance for repeated or prolonged use. The results of clinical application in patients with multi-plane femoral deformities were excellent, and correction with very small residual deformity was achieved in each plane

The aim of this study was to investigate the incidence of dysplasia in the ‘normal’ contralateral hip in patients with unilateral developmental dislocation of the hip (DDH) and to evaluate the long-term prognosis of such hips. A total of 48 patients (40 girls and eight boys) were treated for late-detected unilateral DDH between 1958 and 1962. After preliminary skin traction, closed reduction was achieved at a mean age of 17.8 months (4 to 65) in all except one patient who needed open reduction. In 25 patients early derotation femoral osteotomy of the contralateral hip had been undertaken within three years of reduction, and later surgery in ten patients. Radiographs taken during childhood and adulthood were reviewed. The mean age of the patients was 50.9 years (43 to 55) at the time of the latest radiological review. In all, eight patients (17%) developed dysplasia of the contralateral hip, defined as a centre-edge (CE) angle < 20° during childhood or at skeletal maturity. Six of these patients underwent surgery to improve cover of the femoral head; the dysplasia improved in two after varus femoral osteotomy and in two after an acetabular shelf operation. During long-term follow-up the dysplasia deteriorated to subluxation in two patients (CE angles 4° and 5°, respectively) who both developed osteoarthritis (OA), and one of these underwent total hip replacement at the age of 49 years. In conclusion, the long-term prognosis for the contralateral hip was relatively good, as OA occurred in only two hips (4%) at a mean follow-up of 50 years. Regular review of the ‘normal’ side is indicated, and corrective surgery should be undertaken in those who develop subluxation. Cite this article: Bone Joint J 2014; 96-B:1161–6

PURPOSE: There is an argument in the literature regarding the use of intramedullary nail or the external fixation followed by intramedullary nail in tibial fractures with severe damage of soft tissues, threatened compartment syndrome, open type IIIA fractures and in polytrauma patients. The purpose of this retrospective study was to evaluate the results of non-jointed external fixators as a definite treatment for these type of tibial shaft fractures. MATERIAL AND METHOD: 86 patients (91 tibial shaft fractures) were treated at the authors’ institute with a non-jointed external fixator. The mean patient age was 35 years (range, 15–80). There were 70 male and 16 female patients. The average time of surgery from the accident was 10 hours. The indications for application an external fixator was: severe damage of the soft tissues in 11 fractures, an incipient compartment syndrome in 12 fractures, open type III Gustilo fractures in 57, and 11 tibia fractures in polytrauma patients. According to AO classification 46 fractures were type A, 32 type B and 13 type C. RESULTS: The average follow up was 2.9 years (ranged, 1–5 years). The average operative time was 50 min. Complications included: 3 non-unions, 5 delayed unions, 1 malunions, 1 tibia shortening, 3 superficial infections of soft tissues in open fractures, 26 pin infections and 1 osteomyelitis in open fractures. In 2 patients fat embolism was diagnosed while pulmonary embolism was a complication in 2 patients. Deep venous thrombosis (DVT) developed in 5 patients. A re-operation was performed in 11 out of 91 fractures. Change of the method was necessary in 2 out of 91 fractures. The primary callus in 10 out of 91 fractures was due to the stiffness of the unilateral non-jointed external fixators and did not influence the final results. Mean time of fracture union for the open fractures that did not require change of the method nor bone graft was 25 weeks, while for the closed fractures was 18 weeks. The dynamization of the system and partial weight bearing was started at 6 weeks and all the patients had full weight bearing by the 12th week. CONCLUSION: The unilateral external fixators were the definite treatment in 88 out of 91 fractures. The unilateral external fixators can be used as a definite treatment for tibial shaft fractures in the majority of the cases. Re-operation or change of the method is unusual and must be performed only when there is a delay in callus formation

Purpose: To compare the clinical and radiographic outcomes of a unilateral transpedicular approach with those of standard bilateral transpedicular vertebroplasty. Materials and methods: Retrospective review of vertebroplasty yielded 19 vertebrae in 16 patients that were treated with a standard bilateral approach and 24 vertebrae in 21 patients who were treated with unilateral transpedicular approach. Clinical outcomes, including pain relief and change in pain medication requirements, were compared in the two groups by using chi-square test and Fisher’s exact test. Results: All patients had reported a high reduction in pain in both groups with similar clinical outcomes. Conclusions: Use of a unilateral approach in percutaneus vertebroplasty allows filling of both vertebral halves from a single puncture site with no statistically significant difference in clinical outcome from that of a bilateral transpeduncolar vertebroplasty; this technique permits a shorter operating time with lower rate of complications

Introduction: The aim of this research project was to establish a simple, reliable and repeatable externally fixed femoral fracture model. The rat was selected, as it was a suitable animal for use in a model of fracture repair and ovariectomy induced osteoporosis, both of which were to be investigated in future experiments. There are femoral fracture models described in the literature based on the insertion of an intramedullary nail prior to inducing a fracture. We felt, based on our experience of the unilateral externally fixed mouse fracture model, that external fixation would allow us to carry out radiographical and histological analysis of fracture healing without any of the tissue trauma caused by the insertion and removal of the intramedullary device. Materials and Methods: A unilateral external fixator was chosen due to its simplicity. Four threaded stainless steel pins pass through holes in an aluminium plate with nuts placed on the pin above and below the plate. The holes in the plate were 0.1mm bigger than the pins and unthreaded allowing the plate to slide freely over the pins. Tightening of the upper nut compressed the plate against the lower nut holding the pin securely. 41 female Sprague-Dawley rats, aged between 12 and 18 weeks, were used. They were anaesthetised using a standard mixture of hypnorm and midazolam and analgesia, fluids and antibiotic were administered subcutaneously prior to surgery. The femur was exposed through a lateral approach and a standardised osteotomy was made prior to the application of the fixator plate. Accurate reduction was confirmed visually at the time of surgery and also by way of a post-op x-ray. 25 animals were sacrificed at 4 days and 1, 2, 4, 6 and 8 weeks for histology. The fractured limbs were harvested, fixed, decalcified and paraffin embedded as per standard protocol and serial sections were cut. These were stained with H& E and alcian blue and analysed 15 animals were sacrificed at 4,6 or 8 weeks for biomechanical strength testing. Four-point bending was carried out on freshly harvested femurs stored in normal saline between harvest and testing. Both limbs were tested and the fractured limbs were standardised relative to the unfractured limb. Maximum load to failure was recorded and stiffness was calculated from the load-displacement curve. Results: No post-operative complications of fixation failure or infection occured. On histological assessment at D4 a predominantly lymphocytic inflammatory response was seen within the fracture haematoma. This inflammatory response was replaced with endosteal and periosteal new bone between wks 1 and 2. Bridging of the fracture gap was seen at week 6. Both stiffness and load to failure increased with increasing time. There was a statistically significant improvement in the percentage stiffness and percentage load to failure between 4 and 8 weeks (p=0.03 and p=0.018 respectively). The difference in load to failure between 6 and 8 weeks was also significantly different (p=0.042). Discussion: A simple, reliable and repeatable externally fixed rat femoral fracture model has been established

The purpose of this study was to investigate the efficacy and fusion rates of a unilateral pedicle screw construct supplemented with a translaminar screw in transforaminal lumbar interbody fusion (TLIF). The construct was used with an aim of providing suitable spine stiffness with minimal implant load for spinal fusion. Nineteen consecutive patients who underwent single level TLIF were included in the study. All patients had posterior spinal instrumentation using a unilateral pedicle screw construct with a contralateral translaminar screw. Patients were assessed preoperatively and at two, six, twelve and twenty-four weeks following surgery and at the end of one and two years. At every visit Oswestry disability index score,Visual analogue scale for pain and a pain diagram were recorded. A radiographic exam was also conducted and CT scan was done if there was concern about fusion. The average follow up was twenty-four months. There were twelve males and seven females with an average age of forty-eight years. All patients went on to clinical and radiographic union. Sixteen of nineteen patients had significant clinical improvement on VAS for pain, Oswestry scores and pain medication. Three patients had recurrence of radicular pain on the side of the TLIF leading to reexploration. In all three patients solid fusion was observed but scar tissue was evident and symptoms resolved following redecompression of the foramen. The biomechanical competence of a construct is evidenced by successful fusion. With the advent of minimally invasive techniques to achieve spinal fusion the goal is to use minimal instrumentation without compromising on the final stiffness of the spine. The construct of unilateral pedicle screws supplemented with a trans-laminar screw led to fusion in all our cases. It requires lesser soft tissue dissection and the posterior implants are 56% cheaper

The risk of contra-lateral slip in patients with primary unilateral slipped capital femoral epiphysis (SCFE) is difficult to determine. The material consists of 115 patients operated on because of unilateral SCFE between 1968 – 1991. There were 75 boys (65%) and 40 girls (35%). The mean age at the diagnosis was 12.8 years. Methods. Measurements of such radiological parameters of hip joints as: neck-shaft angle, Alsberg angle, slip angle and Klein’s sign were done. All these measurements were done in three periods. First – at the time of admission, second – at the time of suspected contra-lateral slip and third – at follow up (minimum 2 yrs after subcapital growth plate closure). The mean follow up was 11 yrs (2 – 29). Results. Contra-lateral slip developed in 73% of patients with Alsberg angle (capital physeal – femoral shaft angle) less than 61° and only in 43% of patients with this angle bigger than 61°. No correlation between developing of contra-lateral slip and femoral neck – shaft angle, slip angle and negative Klein’s sign was found. A positive Kline’s sign in the “healthy” hip was observed in 37% of patients with unilateral SCFE at the moment of the fist slip and in all of them contra-lateral slip and/or early coxarthrosis developed. Conclusions. More vertical orientation of the proximal femoral epiphysis can be used as risk factor of the contra-lateral slip in patients with primary unilateral SCFE. Femoral neck – shaft angle, slip angle and negative Kline’s sign in the “healthy” hip have no prognostic value according to the contra-lateral slip. More than 1/3 of the patients with primary unilateral slip developed a symptomatic contra-lateral slip

We studied 50 patients before and after unilateral total hip replacement, and compared them, using gait analysis, with 22 having staged bilateral operations. The average age of the patients was 65 years at the first operation. The mean follow-up was 53 months for the unilateral cases and 27 months, after the second THR, for the bilateral cases. The average interval between first and second THR was 24 months. Patients with bilateral hip disease did not gain optimal function, even on the first side, until both hips had been replaced. Unilateral replacement gave better gait analysis results than did either side after bilateral procedures

The coronal plane lower limb alignment plays an important role in the occurrence and progression in knee osteoarthritis. There have been reports of the valgus knee in patients with unilateral developmental hip dislocation (UDHD) with the relatively small sample size. Besides, few studies have analyzed the lower limb alignment of the contralateral side. The purpose of our study was to identify the coronal plane alignment of both the ipsilateral and the contralateral lower limb in patients with UDHD and find out the difference between patients with Hartofilakidis type II and III. The radiographic data of all UDHD patients who met the inclusion criteria from March 2011 to February 2017 were retrospectively reviewed, including the hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), anatomical lateral distal femoral angle (aLDFA), mechanical proximal tibial angle (MPTA) and the lateral distal tibial angle (LDTA). Besides, the femoral torsion angle was measured on the images of CT scan. The average HKA was 3.42°(range: −4.3–12.8°) on the affected side, and −2.11°(range: −11.4–5.4°) on the contralateral side (P?0.0001). The valgus lower limb alignment on ipsilateral side was most frequently seen in both Hartofilakidis type II (20cases, 51.3%) and type III groups (25cases, 67.6%), whereas for the contralateral side, the neutral alignment in type II group (27 cases, 69.2%) and varus alignment in type III group (19 cases, 51.4%) were most commonly observed. Both the mLDFA (P?0.001) and aLDFA (P?0.001) of ipsilateral side were significantly smaller than those of contralateral side. The average femoral torsion angle was 37.9°(range: 10.4–64.4°) on the affected side, and 27.1°(range: 9.7–45.5°) on the contralateral side (P?0.001). In conclusion, UDHD patients may present with lower limb malalignment on both sides. The valgus lower limb alignment is the most common deformity on ipsilateral side, which is caused by increased femoral torsion angle as well as the decreased aLDFA. The patients with Hartofilakidis type III UDHD may be more prone to present varus alignment deformity than those with Hartofilakidis type II on the contralateral side. The lower limb malalignment and deformity of ipsilateral distal femur should be considered during any surgery involving hip, knee or femur

Rupture of an aneurysm of the common iliac artery is a rare cause of pain in the hip. We describe an elderly hypertensive patient with an aneurysmal rupture of the left common iliac artery who presented with unilateral hip pain masquerading as septic arthritis

Increasing pressure to use rapid recovery care pathways when treating patients undergoing total hip arthroplasty (THA) is evident in current health care systems for numerous reasons. Patient autonomy and health care economics has challenged the ability of THA implants to maintain functional integrity before achieving bony union. Although collared stems have been shown to provide improved axial stability, it is unclear if this stability correlates with activity levels or results in improved early function to patients compared to collarless stems. This study aims to examine the role of implant design on patient activity and implant fixation. The early follow-up period was examined as the majority of variation between implants is expected during this time-frame. Patients (n=100) with unilateral hip OA who were undergoing primary THA surgery were recruited pre-operatively to participate in this prospective randomized controlled trial. All patients were randomized to receive either a collared (n=50) or collarless (n=50) cementless femoral stem. Patients will be seen at nine appointments (pre-operative, < 2 4 hours post-operation, two-, four-, six-weeks, three-, six-months, one-, and two-years). Patients completed an instrumented timed up-and-go (TUG) test using wearable sensors at each visit, excluding the day of their surgery. Participants logged their steps using Fitbit activity trackers and a seven-day average prior to each visit was recorded. Patients also underwent supine radiostereometric analysis (RSA) imaging < 2 4 hours post-operation prior to leaving the hospital, and at all follow-up appointments. Nineteen collared stem patients and 20 collarless stem patients have been assessed. There were no demographic differences between groups. From < 2 4 hours to two weeks the collared implant subsided 0.90 ± 1.20 mm and the collarless implant subsided 3.32 ± 3.10 mm (p=0.014). From two weeks to three months the collared implant subsided 0.65 ± 1.54 mm and the collarless implant subsided 0.45 ± 0.52 mm (p=0.673). Subsidence following two weeks was lower than prior to two weeks in the collarless group (p=0.02) but not different in the collared group. Step count was reduced at two weeks compared to pre-operatively by 4078 ± 2959 steps for collared patients and 4282 ± 3187 steps for collarless patients (p=0.872). Step count increased from two weeks to three months by 6652 ± 4822 steps for collared patients and 4557 ± 2636 steps for collarless patients (p=0.289). TUG test time was increased at two weeks compared to pre-operatively by 4.71 ± 5.13 s for collared patients and 6.54 ± 10.18 s for collarless patients (p=0.551). TUG test time decreased from two weeks to three months by 7.21 ± 5.56 s for collared patients and 8.38 ± 7.20 s for collarless patients (p=0.685). There was no correlation between subsidence and step count or TUG test time. Collared implants subsided less in the first two weeks compared to collarless implants but subsequent subsidence after two weeks was not significantly different. The presence of a collar on the stem did not affect patient activity and function and these factors were not correlated to subsidence, suggesting that initial fixation is instead primarily related to implant design

Posterior approach to the lumbar spine necessarily induces structural damage of paravertebral muscles. In order to avoid these changes, we have started to utilize a microscopic decompression of the spinal canal via an unilateral approach since 1998. The purpose of this study was to evaluate the results of this operative procedure for lumbar spinal canal stenosis. A total of 18 patients, 13 men and five women, were reviewed. The age at the time of surgery ranged from 53years to 78years with a mean of 69.0years. Follow up period averaged 12.3months ranging from one to 32months. As for operative procedure, unilateral paravertebral muscle was retracted laterally and lam-inotomy in the approached side was performed. Following complete decompression of a nerve root in the approached side, microscope was tilted and the inner aspect of lamina in the contralateral side was resected using high-speed drill with a guard of yellow ligament to dural sac and nerve root. Following the procedure, yellow ligament was resected and nerve root in the contralateral side was decompressed. Results: In operation time, blood loss and recovery rate of JOA score, there were no statistical differences compared with ordinal laminotomy cases. Dural sac was well decompressed not only in the hemilaminec-tomy side but also in the contralateral side. All cases showed intensity change of paravertebral muscle in the approached side on T2 weighted MRI. Conclusion: The procedure described here was definitely effective because paravertebral muscle in the contralateral side and midline structure of the lumbar spine could be completely preserved

Bilateral decompression of spinal stenosis may induce instability which compromises outcome. In an attempt to overcome this problem, bilateral decompression can be carried out through a unilateral approach. The ipsilateral side is decompressed by hemi-laminectomy with undercutting partial facetectomy and the contra-lateral side is treated by careful excavation beneath the spinous processes and laminae with preservation of the laminae, posterior ligament complexes and paraspinal muscles. This is achieved with the aid of an operating microscope or loupe and headlight. Previous reports contain little information about outcome and complications. We reviewed 30 patients with bilateral spinal stenosis, but without significant spondylolisthesis who were decompressed bilaterally from a unilateral approach by a single surgeon during a calendar year. They represented a third of our annual operations for spinal stenosis. Thirty patients had 45 levels decompressed. Female to male ratio was 2:1 and average age was 66 years. The average duration of preoperative symptoms was 1.6 years. The mean follow up period was 30 weeks (12 weeks to one year). Assessment was carried out using the Oswestry Disability Index, pre- and post-operative visual analogue pain scores for leg pain and back pain, walking distance and MacNab criteria of patient outcome. Results: improvement in Oswestry Disability Index, pain scores for sciatica and back pain and improved walking distance. All but one case had good or excellent outcome. Complications: one dural tear and two cases with temporary dermatomal sensory change. Whilst the technique is safe, and effective, a longer randomised controlled study is needed to demonstrate any real advantage over traditional approaches

The purpose this prospective, randomized clinical trial was to determine if unilateral or bilateral simultaneous total hip arthroplasty procedures resulted in a differing incidence of fat embolization, degree of hemodynamic compromise, levels of hypoxemia or mental status changes. Also, the incidence of fat embolization was compared between the cemented and cementless total hip arthroplasty in the patients with a unilateral- and bilateral simultaneous total hip arthroplasty. One hundred and fifty-six consecutive patients undergoing primary total hip arthroplasty were enrolled prospectively in the study after giving informed consent. The group consisted of fifty patients undergoing bilateral simultaneous total hip arthroplasty and 106 patients undergoing unilateral total hip arthroplasty. One hundred and three hips were cemented and 103 hips were cementless. To determine the hemodynamic changes and to detect the fat and bone marrow embolization, arterial and right atrial blood samples were obtained before implantation (baseline) and at one, three, five and ten minutes after implantation of the acetabular component. Also, arterial and right atrial blood samples were obtained at one, three, five and ten minutes after implantation of the femoral component. And then blood samples were obtained at twenty-four and forty-eight hours after the operation. Arterial blood pressure, right atrial pressure, arterial oxygen tension and carbon-dioxide tension were monitored at corresponding times. The presence of lipid was determined with oil red O fat stain and the presence of cellular contents of bone marrow was determined with Wright-Giemsa stain. The incidence of fat embolism was not statistically different (P=1.000) between the patients with a bilateral total hip arthroplasty (twenty seven patients or 54 per cent) and the patients with a unilateral total hip arthroplasty (fifty-two patients or 49 per cent). In the semiquantitative analysis of fat globules in both groups, there was no tendency to have a higher number of fat globules in the bilateral group than in the unilateral group. Also, the incidence of bone marrow embolization was not statistically different (P=0.800) between the patients with a bilateral total hip arthroplasty (eight patients or 16 per cent) and the patients with a unilateral total hip arthroplasty (fourteen patients or 13 per cent). There was no statistical difference (P=0.800) in the incidence of the presence of fat globule between the cemented total hip (thirty-four patients or 34 per cent) and the cementless total hip arthroplasty (forty-seven patients or 44 per cent). Also, there was no statistical difference (P=0.627) in the incidence of the presence of bone marrow cells between the cemented total hip arthroplasty (thirteen patients or 13 per cent) and the cement-less total hip arthroplasty (twelve patients or 11 per cent). Four patients with positive bone marrow cells had neurological manifestation. All of these four patients developed diffuse encephalopathy with confusion and agitation for about twenty-four hours. The present study confirmed that the incidence of fat and bone marrow embolization is similar in the patients with a bilateral simultaneous-and unilateral total hip arthroplasty as well as in the patients with cemented and cementless total hip arthroplasty. The patients with bone marrow cell emboli had a significantly lower arterial oxygen tension (p=0.022) and oxygen saturation (p=0.017) than the patients without bone marrow cell emboli. On the contrary, the number of fat globules did not affect the perioperative hemodynamic changes. Encephalopathy is related to the biochemical and/or mechanical changes by bone marrow cells

Salter innominate osteotomy is an effective reconstructive procedure for the treatment of developmental dysplasia of the hip (DDH), but some children have a poor outcome at skeletal maturity. In order to investigate factors associated with an unfavourable outcome, we assessed the development of the contralateral hip. We retrospectively reviewed 46 patients who underwent a unilateral Salter osteotomy at between five and seven years of age, with a mean follow-up of 10.3 years (7 to 20). The patients were divided into three groups according to the centre–edge angle (CEA) of the contralateral hip at skeletal maturity: normal (> 25°, 22 patients), borderline (20° to 25°, 17 patients) and dysplastic (<  20°, 7 patients). The CEA of the affected hip was measured pre-operatively, at eight to nine years of age, at 11 to 12 years of age and at skeletal maturity. The CEA of the affected hip was significantly smaller in the borderline and dysplastic groups at 11 and 12 years of age (p = 0.012) and at skeletal maturity (p = 0.017) than in the normal group. Severin group III was seen in two (11.8%) and four hips (57.1%) of the borderline and dysplastic groups, respectively (p < 0.001). . Limited individual development of the acetabulum was associated with an unfavourable outcome following Salter osteotomy. Cite this article: Bone Joint J 2014;96-B:1419–23