Aims. The presence of
Cervical spine
Objectives. Understanding lumbar facet joint involvement and biomechanical changes post spinal fusion is limited. This study aimed to establish an in vitro model assessing mechanical effects of fusion on human lumbar facet joints, employing synchronized motion, pressure, and stiffness analysis. Methods and Results. Seven human lumbar spinal units (age 54 to 92, ethics 15/YH/0096) underwent fusion via a partial nucleotomy model mimicking a lateral cage approach with PMMA cement injection. Mechanical testing pre and post-fusion included measuring compressive displacement and load, local motion capture, and pressure mapping at the facet joints. pQCT imaging (82 microns isotropic) was carried out at each stage to assess the integrity of the vertebral endplates and quantify the amount of cement injected. Before fusion, relative facet joint displacement (6.5 ± 4.1 mm) at maximum load (1.1 kN) exceeded crosshead displacement (3.9 ± 1.5 mm), with loads transferred across both facet joints. After fusion,
Abstract. Objectives. While spinal fusion is known to be associated with adjacent disc degeneration, little is known on the role of the facet joints in the process, and whether their altered biomechanics following fusion plays a role in further spinal degeneration. This work aimed to develop a model and method to sequentially measure the effects of spinal fusion on lumbar facet joints through synchronisation of both motion analysis, pressure mapping and mechanical analysis. Methods. Parallel measurements of mature ovine lumbar facet joints (∼8yr old, n=3) were carried out using synchronised load and displacement measurements, motion capture during loading and pressure mapping of the joint spaces during loading. Functional units were prepared and cemented in PMMA endcaps. Displacement-controlled compression measurements were carried out using a materials testing machine (3365, Instron, USA) at 1 mm/min up to 950 N with the samples in a neutral position, while motion capture of the facet joints during compression was carried out using orthogonal HD webcams (Logitech, Switzerland) to measure the displacement of key facet joint features. The pressure mapping of load transfer during displacement was carried out using a flexible pressure sensor (6900 series, Tekscan, USA). Each sample was imaged at an isotropic resolution of 82 microns using a μCT scanner (XtremeCT, Scanco, Switzerland) to quantify the curvature within the facet joints. Results. Relative facet joint displacement under load, in a neutral position, showed more displacement (2.36 ±1.68 mm) compared to the cross-head when under compression (2.06 ±1.19 mm). Motion capture indicated the relative displacement of the facet joints was more posterior with some lateral motion. For five of the six facet joints, pressure measurement was possible only on 24±7 % of the surface due to the large change in curvature. Partially measured loads through the
We carried out a study to determine the effect of
Traumatic unilateral
Summary. Nucleotomy almost doubles the transmitted forces on the facet joints in human lumbar spine, regardless of the amount of removed nucleus pulposus. Introduction. Low back pain involves the lumbar facet joints in 15% to 45% of the cases. The surgical intervention, nucleotomy, might also lead to painful
Introduction. Mechanical integrity of patella can be weakened by the technique of removing the articulating surface. The senior author developed the technique of maintaining subchondral bone of the lateral patellar
Introduction and Aims: The aim of this paper is to review C1-C2
Purpose: Facet joint arthrosis is an entity that can have a key role in the etiology of low back pain, especially with hyperextension, and is a key component of surgical planning, especially when considering disc arthroplasty. Plain films and MRI are most commonly utilized as the initial imaging of choice for low back pain, but these methods may not truly allow an accurate assessment of
The supraspinatus tendon (SP) often ruptures. Gray established that the tendinous insertion always attaches to the highest
Abstract. Objective. Flexible stabilisation has been utilised to maintain spinal mobility in patients with early-stage lumbar spinal stenosis (LSS). Previous literature has not yet established any non-fusion solution as a viable treatment option for patients with severe posterior degeneration of the lumbar spine. This feasibility study evaluates the mean five-year outcomes of patients treated with the TOPS (Total Posterior Spine System)
Introduction: The effect of
Aim: To investigate the efficacy of the Insall tube realignment procedure when used to treat osteoarthrosis of the lateral
Background. Surgical resection of middle
Hypertrophy of lumbar articular
Introduction. Anteromedial gonarthrosis is a common well described pattern of knee osteoarthritis with cartilage wear beginning in the anteromedial quadrant of the medial tibial plateau in the presence of an intact and functioning ACL. It is well known that mechanical factors such as limb alignment and meniscal integrity affect the progression of arthritis and there is some evidence that the morphology of the tibial plateau may be a risk factor in the development of this disease. The extension
Introduction: Anteromedial gonarthrosis is a common well described pattern of knee osteoarthritis with cartilage wear beginning in the anteromedial quadrant of the medial tibial plateau in the presence of an intact and functioning ACL. It is well known that mechanical factors such as limb alignment and meniscal integrity affect the progression of arthritis and there is some evidence that the morphology of the tibial plateau may be a risk factor in the development of this disease. The extension
We treated 36 patients with unilateral
Fractures of the anteromedial
Peroneal spastic flatfeet without coalition or other known etiologies in adolescence remain a challenge to manage. We present eight such cases with radiological and surgical evidence of bony abnormalities in the subtalar region just anterior to the posterior
We describe a lumbar
Painful peroneal spastic flatfeet without coalition or other known etiologies in adolescence, remains a difficult condition to treat. We present eight such cases with radiological and surgical evidence of bony abnormalities in the lateral subtalar region just anterior to the posterior
Introduction. Historically, surgeons have focused on isolated simple coalition resection in symptomatic tarsal coalition with concomitant rigid flat foot. However, a review of literature suggests that coalitions with severe preoperative planovalgus malposition treated with resection alone are associated with continued disability and deformity. We believe that concomittant severe flatfoot should be considered as much as a pathological component and pain generator as the coalition itself. Our primary hypothesis is that simple resection of middle
The requirements for a motion segment fusion for degenerative disc disease are relief from symptoms from a solid union with minimal damage to surrounding tissue. This is possible with the ‘Mini PLIF’ using the B Twin cages and
Aim. Historically, surgeons have focused on isolated simple coalition resection in symptomatic tarsal coalition with concomitant rigid flat foot. However, recent evidence suggests that coalitions with severe preoperative planovalgus malposition treated with resection alone are associated with continued disability and deformity. We believe that concomitant severe flatfoot should be considered as much as a pathological component and pain generator as the coalition itself. Our primary hypothesis is that simple resection of middle
The aim of this study was to assess the benefit and durability of isolated lateral release for advanced osteoarthritis of the lateral
Bilateral interlocking of the articular
We report 13 patients with missed bilateral
Awake Rapid Heavy-Weight Closed Reduction (ARHWCR) with weights from 18 to 72 kg was used to reduce six unilateral and nine bilateral cervical
The cervical spine is the most vulnerable segment in high velocity injuries. Bifacet dislocations are associated with significant soft tissue damage and neurological deficit. Management of delayed presentation of cervical
Objective. To identify any difference in clinical outcome between Intra-Capsular
Cervical total disc replacement has been in practice for years now as a viable alternative to cervical fusion in suitable cases, aspiring to preserve spinal motion and prevent adjacent segment disease. Reports are rife that neck pain emerges as an annoying feature in the early postoperative period. The facet joint appears to be the most likely source of pain. 50 patients were prospectively followed up through 5 years after having received disc replacement surgery, indicated for symptomatic soft disc herniation of the cervical spine presenting with radiculopathy.
We excluded those with degenerative trophic changes of the cervical spine, focal instability, trauma, osteoporosis, previous cervical spine surgery, previous infection, ossifying axial skeletal disease and inflammatory spondyloarthritides. The device used was an unconstrained implant with stabilizing teeth. Over the 5 years, we studied their postoperative comfort level via the Neck Disability Index (NDI) and Visual Analogue Score (VAS). Pre-operative and post-operative analysis of the sagittal axis and of involved facet joints were done. 22 patients suffered postoperative neck pain as reflected by the NDI and VAS scores. Of these, 10 reported of neck pain even 24 months after surgery. However, none were neurologically worse and all patients returned to their pre-morbid functions and were relieved of pain by 28 months. All 22 patients reported of rapid dissolution of neckache after peri-facetal injections of steroids were done under image guidance. We draw attention to the facet joint as the pain generator, triggered by inappropriate implant height, eccentric stresses via hybrid constructs, eccentric loading due to unconstrained devices and unaddressed Luschka joint degeneration. Such factors require careful selection of patients for surgery, necessitate proper pre-operative templating and call for appropriate technical solutions during surgery.
• All were skeletally mature and aged between 22 to 50.
• Single surgeon (first author)
Facet joint osteoarthritis (FJOA) is a prominent clinical hallmark of degenerative spine disorders. During disease progression, cartilage and subchondral bone tissues undergo increased turnover and remodeling. The structural changes to the subchondral tissue of FJOA have not been studied thus far. In this study, we performed a micro computed tomography (µCT) study of the subchondral cortical plate (SCP) and trabecular bone (STB) in FJOA and determined osteoarthritis-specific alterations. Twenty-four patients (11 male, 13 female, median age 65) scheduled for decompression and stabilization surgery for degenerative spinal stenosis were included in this study. FJOA specimens were harvested during surgery and analyzed by µCT. Bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp) and trabecular number (Tb.N) were evaluated using CT Analyser. Lumbar facet joints without chondropathy from cadaveric specimens (9 male, 6 female, median age 57) served as healthy controls. Age-, gender- and disease-specific effects were identified by ANOVA (Introduction
Methods
A case of a ganglion arising from a distal lumbar articular facet joint associated with low back pain and sciatica is reported and the pertinent literature reviewed.
To determine whether spinal
Aims. The purpose of this retrospective study was to investigate the
clinical relevance of increased facet joint distraction as a result
of anterior cervical decompression and fusion (ACDF) for trauma. Patients and Methods. A total of 155 patients (130 men, 25 women. Mean age 42.7 years;
16 to 87) who had undergone ACDF between 1 January 2001 and 1 January
2016 were included in the study. Outcome measures included the Neck
Disability Index (NDI) and visual analogue scale (VAS) for pain.
Lateral cervical spine radiographs taken in the immediate postoperative
period were reviewed to compare the interfacet distance of the operated
segment with those of the facet joints above and below. Results. There was a statistically significant relationship between greater
facet distraction and increased NDI and VAS pain scores. This was
further confirmed by Spearman correlation, which showed evidence
of a moderate correlation between both NDI score and
Ulnocarpal impaction (UCI) is a common cause of ulnar-sided wrist pain. UCI typically occurs in wrists with positive ulnar variance, which causes altered loading mechanics between the ulnar head, lunate and triquetrum. However, many individuals with positive ulnar variance never develop UCI, and some with neutral or negative ulnar variance do experience UCI. This suggests that other variables contribute to the development of UCI. Suspected culprits include lunate morphology, and dynamic changes with loaded (grip) pronation. If these anatomic variations are contributing to UCI, we expect them to influence functional impairment scores. Therefore, the objective of this study was to evaluate the relationship between radiographic parameters and pre-surgical upper extremity patient-rated outcomes scores (PROS) in patients with a diagnosis of UCI. Retrospective cohort study of patients undergoing ulnar shortening osteotomy or arthroscopic wafer procedure for UCI. Data derived from prospectively collected departmental database that captured demographic, clinical, functional and radiographic information. Radiographic parameters evaluated were: lunate morphology [presence vs. absence of hamate
Despite the current trend favoring surgical treatment of displaced intra-articular calcaneal fractures (DIACFs), studies have not been able to demonstrate superior functional outcomes when compared to non-operative treatment. These fractures are notoriously difficult to reduce. Studies investigating surgical fixation often lack information about the quality of reduction even though it may play an important role in the success of this procedure. We wanted to establish if, amongst surgically treated DIACF, an anatomic reduction led to improved functional outcomes at 12 months. From July 2011 to December 2020, at a level I trauma center, 84 patients with an isolated DIACF scheduled for surgical fixation with plate and screws using a lateral extensile approach were enrolled in this prospective cohort study and followed over a 12-month period. Post-operative computed tomography (CT) imaging of bilateral feet was obtained to assess surgical reduction using a combination of pre-determined parameters: Böhler's angle, calcaneal height, congruence and articular step-off of the posterior
Despite the current trend favoring surgical treatment of displaced intra-articular calcaneal fractures (DIACFs), studies have not been able to demonstrate superior functional outcomes when compared to non-operative treatment. These fractures are notoriously difficult to reduce. Studies investigating surgical fixation often lack information about the quality of reduction even though it may play an important role in the success of this procedure. We wanted to establish if, amongst surgically treated DIACF, an anatomic reduction led to improved functional outcomes at 12 months. From July 2011 to December 2020, at a level I trauma center, 84 patients with an isolated DIACF scheduled for surgical fixation with plate and screws using a lateral extensile approach were enrolled in this prospective cohort study and followed over a 12-month period. Post-operative computed tomography (CT) imaging of bilateral feet was obtained to assess surgical reduction using a combination of pre-determined parameters: Böhler's angle, calcaneal height, congruence and articular step-off of the posterior
Displaced intraarticular calcaneal fractures are debilitating injuries with significant socioeconomic and psychological effects primarily affecting patients in active age between 30 and 50 years. Recently, minimally and less invasive screw fixation techniques have become popular as alternative to locked plating. The aim of this study was to analyze biomechanically in direct comparison the primary stability of 3 different cannulated screw configurations for fixation of Sanders type II-B intraarticular calcaneal fractures. Fifteen fresh-frozen human cadaveric lower limbs were amputated mid-calf and through the Chopart joint. Following, soft tissues at the lateral foot side were removed, whereas the medial side and Achilles tendon were preserved. Reproducible Sanders type II-B intraarticular fracture patterns were created by means of osteotomies. The proximal tibia end and the anterior-inferior aspect of the calcaneus were then embedded in polymethylmethacrylate. Based on bone mineral density measurements, the specimens were randomized to 3 groups for fixation with 3 different screw configurations using two 6.5 mm and two 4.5 mm cannulated screws. In Group 1, two parallel longitudinal screws entered the tuber calcanei above the Achilles tendon insertion and proceeded to the anterior process, and two transverse screws fixed the posterior
We scanned 25 left knees in healthy human subjects
using MRI. Multiplanar reconstruction software was used to take
measurements of the inferior and posterior
From a search of MRI reports on knees, 20 patients were identified with evidence of early anteromedial osteoarthritis without any erosion of bone and a control group of patients had an acute rupture of the anterior cruciate ligament. The angle formed between the extension and flexion
We examined the reliability of radiological findings in predicting segmental instability in 112 patients (56 men, 56 women) with a mean age of 66.5 years (27 to 84) who had degenerative disease of the lumbar spine. They underwent intra-operative biomechanical evaluation using a new measurement system. Biomechanical instability was defined as a segment with a neutral zone >
2 mm/N. Risk factor analysis to predict instability was performed on radiographs (range of segmental movement, disc height), MRI (Thompson grade, Modic type), and on the axial CT appearance of the
Aims. No randomized comparative study has compared the extensile lateral approach (ELA) and sinus tarsi approach (STA) for Sanders type 2 calcaneal fractures. This randomized comparative study was conducted to confirm whether the STA was prone to fewer wound complications than the ELA. Methods. Between August 2013 and August 2018, 64 patients with Sanders type 2 calcaneus fractures were randomly assigned to receive surgical treatment by the ELA (32 patients) and STA (32 patients). The primary outcome was development of wound complications. The secondary outcomes were postoperative complications, pain scored of a visual analogue scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) score, 36-item Short Form health survey, operative duration, subtalar joint range of motion (ROM), Böhler’s angle and calcaneal width, and posterior
Distal radius fractures have an incidence rate of 17.5% among all fractures. Their treatment in case of comminution, commonly managed by volar locking plates, is still challenging. Variable-angle screw technology could counteract these challenges. Additionally, combined volar and dorsal plate fixation is valuable for treatment of complex fractures at the distal radius. Currently, biomechanical investigation of the competency of supplemental dorsal plating is scant. The aim of this study was to investigate the biomechanical competency of double-plated distal radius fractures in comparison to volar locking plate fixation. Complex intra-articular distal radius fractures AO/OTA 23-C 2.1 and C 3.1 were created by means of osteotomies, simulating dorsal defect with comminution of the lunate
Background. Open subtalar arthrodesis has been associated with a moderate rate of non-union, as high 16.3%, and high rates of infection and nerve injury. Performing this operation arthroscopically serves to limit the disruption to the soft tissue envelope, improve union rates and reduce infection. Our study describes our outcomes and experience of this operation. Method. Retrospective review of all patients who underwent an arthroscopic subtalar arthrodesis between 2023 and 2008. We excluded patients undergoing concurrent adjacent joint arthrodesis. The primary aim was to report on rates of union. Secondary outcomes included reporting on conversion to open procedure, duration of surgery, infection, and iatrogenic injury to surrounding structures. Results. 135 patients were included in the final analysis. 129 patients (95.5%) achieved union. The median time to fusion was 98 days. All cases were performed through sinus tarsi portals. 38 cases were performed with an additional posterolateral portal. Most cases (107/77%) were performed with 2 screws. 3 cases (2.2%) were converted to open procedures. The median tourniquet time was 86 minutes but available in only 88 (65%) cases. There were 4 (2.9%) superficial infections and no deep infections. 1 patient sustained an injury to FHL and there were no reported nerve injuries. Conclusions. At present this is the largest series of arthroscopic subtalar arthrodeses. We demonstrate that this operation can achieve high rates of union with low rates of infection with an equally low likelihood of needing to convert to an open procedure with modest operative times. In our experience the addition of a posterolateral portal does not appear to increase the incidence of nerve injury and aids in the visualisation of all 3
Aim. By gaining insight into the Quality of Life (QoL) status and occurrence of complications, critical
Introduction. The aetiology of hallux valgus is almost certainly multifactoral.
The biomechanics of the first ray is a common factor to most. There
is very little literature examining the anatomy of the proximal
metatarsal articular surface and its relationship to hallux valgus
deformity. Methods. We examined 42 feet from 23 specimens in this anatomical dissection
study. Results. This analysis revealed three distinct articular subtypes. Type
1 had one single
We previously reported that osteoblasts at the curve apex in adolescent idiopathic scoliosis (AIS) exhibit a differential phenotype, compared to non-curve osteoblasts(1). However, the Hueter-Volkmann principle on vertebral body growth in spinal deformities (2) suggests this could be secondary to altered biomechanics. This study examined whether non-curve osteoblasts subjected to mechanical strain resemble the transcriptomic phenotype of curve apex osteoblasts.
The use of intraoperative navigation and robotic surgery for minimally invasive lumbar fusion has been increasing over the past decade. The aim of this study is to evaluate postoperative clinical outcomes, intraoperative parameters, and accuracy of pedicle screw insertion guided by intraoperative navigation in patients undergoing lumbar interbody fusion for spondylolisthesis. Patients who underwent posterior lumbar fusion interbody using intraoperative 3D navigation since December 2021 were included. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Short Form Health Survey-36 (SF-36) were assessed preoperatively and postoperatively at 1, 3, and 6 months. Screw placement accuracy, measured by Gertzbein and Robbins classification, and facet joint infringement, measured by Yson classification, were assessed by intraoperative Cone Beam CT scans performed at the end of instrumentation. Finally, operation time, intraoperative blood loss, hospital stay, and screw insertion time were evaluated. This study involved 50 patients with a mean age of 63.7 years. VAS decreased from 65.8±23 to 20±22 (p<.01). ODI decreased from 35.4%±15 to 11.8%±14 (p<.01). An increase of SF-36 from 51.5±14 to 76±13 (p<.01) was demonstrated. The accuracy of “perfect” and “clinically acceptable” pedicle screw fixation was 89.5% and 98.4%, respectively. Regarding
We dissected 12 fresh-frozen leg specimens to
identify the insertional footprint of each fascicle of the Achilles tendon
on the calcaneum in relation to their corresponding muscles. A further
ten embalmed specimens were examined to confirm an observation on
the retrocalcaneal bursa. The superficial part of the insertion
of the Achilles tendon is represented by fascicles from the medial
head of the gastrocnemius muscle, which is inserted over the entire
width of the inferior
Abstract. Purpose. Recently several authors have suggested a correlation between posterior tibial slope (PTS) and sagittal stability of the knee. However, there is a lack of consensus in the literature relating to measurement, normal values and important values to guide treatment. We performed a systematic literature review looking at PTS and cruciate ligament surgery. Our aim was to define a gold standard measurement technique, determine normal ranges and important values for consideration during cruciate ligament surgery. Methods. Electronic searches of MEDLINE (PubMed), CINAHL, Cochrane, Embase, ScienceDirect, and NICE in June 2020 were completed. Inclusion criteria were original studies in peer-reviewed English language journals. A quality assessment of included studies was completed using the Methodological Index for Non-Randomized Studies (MINORS) Criteria. Results. Two-hundred and twenty-one papers were identified; following exclusions 34 papers were included for data collection. The mean MINORS score for non-comparative studies was 13.8 and for comparative studies 20.4, both indicating fair to good quality studies. A large variation in PTS measurement technique was identified, resulting in a wide range of values reported. In addition, there appears to be significant variation between different races, ages and genders. Conclusion. We demonstrated a lack of consensus in the literature relating to various
Surgical trainees are finding it increasingly more challenging to meet operative requirements and coupled with the effects of COVID-19, we face a future of insufficiently trained surgeons. As a result, virtual reality (VR) simulator training has become more prevalent and whilst more readily accepted in certain arthroscopic fields, its use in hip arthroscopy (HA) remains novel. This project aimed to validate VR high-fidelity HA simulation and assess its functional use in arthroscopic training. Seventy-two participants were recruited to perform two basic arthroscopic tasks on a VR HA simulator, testing hip anatomy, scope manipulation and triangulation skills. They were stratified into novice (39) and experienced (33) groups based on previous arthroscopy experience. Metric parameters recorded from the simulator were used to assess construct validity. Face validity was evaluated using a Likert-style questionnaire. All recordings were reviewed by 2 HA experts for blinded ASSET score assessment. Experienced participants were significantly faster in completing both tasks compared with novice participants (p<0.001). Experienced participants damaged the acetabular and femoral cartilage significantly less than novice participants (p=0.011) and were found to have significantly reduced path length of both camera and instrument across both tasks (p=0.001, p=0.007), demonstrating significantly greater movement economy. Total ASSET scores were significantly greater in experienced participants compared to novice participants (p=0.041) with excellent correlation between task time, cartilage damage, camera and instrument path length and corresponding ASSET score constituents. 62.5% of experienced participants reported a high degree of realism in all
Introduction. Kinematics post-TKA are complex; component alignment, component geometry and the patient specific musculoskeletal environment contribute towards the kinematic and kinetic outcomes of TKA. Tibial rotation in particular is largely uncontrolled during TKA and affects both tibiofemoral and patellofemoral kinematics. Given the complex nature of post- TKA kinematics, this study sought to characterize the contribution of tibial tray rotation to kinematic outcome variability across three separate knee geometries in a simulated framework. Method. Five 50. th. percentile knees were selected from a database of planned TKAs produced as part of a pre-operative dynamic planning system. Virtual surgery was performed using Stryker (Kalamazoo, MI) Triathlon CR and PS and MatOrtho (Leatherhead, UK) SAIPH knee medially stabilised (MS) components. All components were initially planned in mechanical alignment, with the femoral component neutral to the surgical TEA. Each knee was simulated through a deep knee bend, and the kinematics extracted. The tibial tray rotational alignment was then rotated internally and externally by 5° & 10°. The computational model simulates a patient specific deep knee bend and has been validated against a cadaveric Oxford Knee Rig. Preoperative CT imaging was obtained, landmarking to identify all patient specific axes and ligament attachment sites was performed by pairs of trained biomedical engineers. Ethics for this study is covered by Bellberry Human Research Ethics Committee application number 2012-03-710. Results and Discussion. From the 360 Knee Systems database, 1847 knees were analysed, giving an average coronal alignment of 4.25°±5.66° varus. Five knees were selected with alignments between 4.1° and 4.3° varus. Kinematic outcomes were averaged over the 5 knees. The component geometries resulted in characteristically distinct kinematics, in which femoral rollback was most constrained by the PS components, whereas tibiofemoral axial rotation was most constrained in MS components. Patella lateral shift was comparable amongst all components in extension, medialising in flexion. Patella shift remained more lateral in MS components compared to PS and CR. Average patella lateral shift, medial and lateral
Aims. It remains controversial whether patellofemoral joint pathology is a contraindication to lateral unicompartmental knee arthroplasty (UKA). This study aimed to evaluate the effect of preoperative radiological degenerative changes and alignment on patient-reported outcome scores (PROMs) after lateral UKA. Secondarily, the influence of lateral UKA on the alignment of the patellofemoral joint was studied. Methods. A consecutive series of patients who underwent robotic arm-assisted fixed-bearing lateral UKA with at least two-year follow-up were retrospectively reviewed. Radiological evaluation was conducted to obtain a Kellgren Lawrence (KL) grade, an Altman score, and alignment measurements for each knee. Postoperative PROMs were assessed using the Kujala (Anterior Knee Pain Scale) score, Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS JR), and satisfaction levels. Results. A total of 140 knees (130 patients) were identified for analysis. At mean 4.1 years (2.0 to 8.5) follow-up, good to excellent Kujala scores were reported. The presence of mild to moderate preoperative patellofemoral joint osteoarthritis had no impact on these scores (KL grade 0 vs 1 to 3, p = 0.203; grade 0 to 1 vs 2 to 3, p = 0.674). Comparable scores were reported by patients with osteoarthritis (Altman score of ≥ 2) evident on either the medial or lateral patellofemoral joint
Aims. The aim of this study was to investigate the changes in femoral
trochlear morphology following surgical correction of recurrent
patellar dislocation associated with trochlear dysplasia in children. Patients and Methods. A total of 23 patients with a mean age of 9.6 years (7 to 11)
were included All had bilateral recurrent patellar dislocation associated
with femoral trochlear dysplasia. The knee with traumatic dislocation
at the time of presentation or that had dislocated most frequently
was treated with medial patellar retinacular plasty (Group S). The
contralateral knee served as a control and was treated conservatively
(Group C). All patients were treated between October 2008 and August
2013. The mean follow-up was 48.7 months (43 to 56). Axial CT scans
were undertaken in all patients to assess the trochlear morphological
characteristics on a particular axial image which was established
at the point with the greatest epicondylar width based on measurements
preoperatively and at the final follow-up. Results. Preoperatively, there were no statistically significant differences
between the trochlear morphology in the two groups (sulcus angle,
p 0.852; trochlear groove depth, p 0.885; lateral trochlear inclination,
p 0.676; lateral-to-medial
Treatment of comminuted intraarticular calcaneal fractures remains controversial and challenging. Anatomic reduction with stable fixation has demonstrated better outcomes than nonoperative treatment of displaced intraarticular fractures involving the posterior
BACKGROUND. Conventional TKA surgery attempts to restore patients to a neutral alignment, and devices are designed with this in mind. Neutral alignment may not be natural for many patients, and may cause dissatisfaction [1]. To solve this, kinematical alignment (KA) attempts to restore the native pre-arthritic joint-line of the knee, with the goal of improving knee kinematics and therefore patient's function and satisfaction [1]. Proper prosthetic trochlea alignment is important to prevent patella complications such as instability or loosening. However, available TKA components have been designed for mechanical implantation, and concerns remain relating the orientation of the prosthetic trochlea when implants are kinematically positioned. The goal of this study is to investigate how a currently available femoral component restores the native trochlear geometry of healthy knees when virtually placed in kinematic alignment. METHODS. The healthy knee OAI (Osteoarthritis Initiative) MRI dataset was used. 36 MRI scans of healthy knees were segmented to produce models of the bone and cartilage surfaces of the distal femur. A set of commercially available femoral components was laser scanned. Custom 3D planning software aligned these components with the anatomical models: distal and posterior condyle surfaces of implants were coincident with distal and posterior condyle surfaces of the cartilage; the anterior flange of the implant sat on the anterior cortex; the largest implant that fitted with minimal overhang was used, performing ‘virtual surgery’ on healthy subjects. Software developed in-house fitted circles to the deepest points in the trochlear grooves of the implant and the cartilage. The centre of the cartilage trochlear circle was found and planes, rotated from horizontal (0%, approximately cutting through the proximal trochlea) through to vertical (100%, cutting through the distal trochlea) rotated around this, with the axis of rotation parallel to the flexion
Aim:. The purpose of this study was to identify factors (radiographic and MRI) which may be important in determining whether a degenerative spondylolisthesis at L4/5 is mobile. Method:. We identified 60 consecutive patients with a degenerative spondylolisthesis(DS) at L4/5 and reviewed their imaging. Patients were separated into groups on the basis of whether the DS was mobile (group A) or non-mobile (Group B) when comparing the upright plain lumbar radiograph to the supine MRI. We assessed the lumbar lordosis, pelvic incidence, sacral slope, pelvic tilt, grade of the slip,
Conventional TKA surgery attempts to restore patients to a neutral alignment, and devices are designed with this in mind. Neutral alignment may not be natural for many patients, and may cause dissatisfaction. To solve this, kinematical alignment (KA) attempts to restore the native pre-arthritic joint-line of the knee, with the goal of improving knee kinematics and therefore patient's function and satisfaction. Proper prosthetic trochlea alignment is important to prevent patella complications such as instability or loosening. However, available TKA components have been designed for mechanical implantation, and concerns remain relating the orientation of the prosthetic trochlea when implants are kinematically positioned. The goal of this study is to investigate how a currently available femoral component restores the native trochlear geometry of healthy knees when virtually placed in kinematic alignment. The healthy knee OAI (Osteoarthritis Initiative) MRI dataset was used. 36 MRI scans of healthy knees were segmented to produce models of the bone and cartilage surfaces of the distal femur. A set of commercially available femoral components was laser scanned. Custom 3D planning software aligned these components with the anatomical models: distal and posterior condyle surfaces of implants were coincident with distal and posterior condyle surfaces of the cartilage; the anterior flange of the implant sat on the anterior cortex; the largest implant that fitted with minimal overhang was used, performing ‘virtual surgery’ on healthy subjects. Software developed in-house fitted circles to the deepest points in the trochlear grooves of the implant and the cartilage. The centre of the cartilage trochlear circle was found and planes, rotated from horizontal (0%, approximately cutting through the proximal trochlea) through to vertical (100%, cutting through the distal trochlea) rotated around this, with the axis of rotation parallel to the flexion
Abstract. Background. Conventional TKR aims for neutral mechanical alignment which may result in a smaller lateral distal femoral condyle resection than the implant thickness. We aim to explore the mismatch between implant thickness and bone resection using 3D planning software used for Patient Specific Instrumentation (PSI) TKR. Methods. This is a retrospective anatomical study from pre-operative MRI 3D models for PSI TKR. Cartilage mapping allowed us to recreate the native anatomy, enabling us to quantify the mismatch between the distal lateral femoral condyle resection and the implant thickness. Results. We modelled 292 knees from PSI TKR performed between 2012 and 2015. There were 225 varus knees and 67 valgus knees, with mean supine hip-knee-angle of 5.6±3.1 degrees and 3.6±4.6 degrees, respectively. In varus knees, the mean cartilage loss from medial and lateral femoral condyle was 2.3±0.7mm and 1.1±0.8mm respectively; the mean overstuffing of the lateral condyle 1.9±2.2mm. In valgus knees, the mean cartilage loss from medial and lateral condyle was 1.4±0.8mm and 1.5±0.9mm respectively; the mean overstuffing of the lateral condyle was 4.1±1.9mm. Conclusions. Neutral alignment TKR often results in overstuffing of the lateral condyle. This may increase the patello-femoral pressure at the lateral
Patellofemoral joint degeneration is often considered a contraindication to medial unicompartmental knee replacement. We examined the validity of this preconception using information gathered prospectively on the intra-operative status of the patellofemoral joint in 824 knees in 793 consecutive patients who underwent Oxford unicondylar knee replacement for anteromedial osteoarthritis. All operations were performed between January 1998 and September 2005. A five-point grading system classified degeneration of the patellofemoral joint from none to full-thickness cartilage loss. A subclassification of the presence or absence of any full-thickness cartilage loss was subsequently performed to test selected hypotheses. Outcome was evaluated independently by physiotherapists using the Oxford and the American Knee Society Scores with a minimum follow-up of one year. Full-thickness cartilage loss on the trochlear surface was observed in 100 of 785 knees (13%), on the medial
We retrospectively analysed the MR scans of 25 patients with patellofemoral dysplasia and ten control subjects, to assess whether there was any change in the morphology of the patella along its vertical length. Ratios were calculated comparing the size of the cartilaginous and subchondral osseous surfaces of the lateral and medial
Introduction: With increasing availability of CT scans their use in the investigation of the subtalar joint increases, whilst we continue to use plain x-ray. Using a standardised reporting protocol, we graded x-rays and CT scans to compare the diagnosis made using each modality. Materials and Methods: An atlas and reporting system of the subtalar joint was designed using a modification of Kellgren and Lawrence’s system. 50 consecutive CT scans of the subtalar joint were identified and saved along with paired plain x-rays of the foot and ankle. All investigations were anonymised. Scans were excluded if there were no plain films or there was evidence of previous trauma. Orthopaedic surgeons were asked to report on the 50 CT scans and 50 plain radiographs using the reporting protocol, commenting on two components for each investigation; the anterior and middle
Background. NICE guidance suggests that caudal epidural injections of steroid and local anaesthetic may be considered for acute and severe sciatica, however studies have demonstrated limited long-term benefit and impact on future surgery. This study aimed to investigate the use of caudal epidural injections in a district general hospital setting and the rate of subsequent operation. Methods. All patients undergoing caudal epidural injection between 1. st. January and 30. th. June 2015 were included. Records were reviewed to obtain diagnosis, pre- and post-epidural clinical findings, prior interventions, and subsequent operations. Results. A total of 141 patients underwent a caudal epidural, with a median age of 63 (18 – 90). 37 patients went on to surgical intervention within 3 years, resulting in a conversion rate of 26.1%. Amongst those not requiring surgery, 59 (56.19%) had disc herniation, 42 (40%) stenosis, 4 spondylolisthesis, and 1 a
Introduction. Tibial patho-morphology has been described as a factor that predisposes to medial compartment osteoarthritis of the knee in 2D analysis. The aim of this study was to investigate whether the morphology of normal and pre-OA medial compartments are really different in 3 dimensions. Method. A total of 20 normal (group A) and 20 pre-OA knees (group B) were included. Group A consisted of contra-lateral knees of young patients awaiting hip surgery and group B of asymptomatic contra-lateral knees of patients awaiting unicompartmental knee arthroplasty (UKA). Using 3D reconstructions from CT scans, femurs were aligned to the transcondylar and anatomical axes. The medial femoral extension
Endoscopic spine surgery is a promising and minimally invasive technique for the treatment of disc herniation and spinal stenosis. However, the literature on the outcome of interlaminar endoscopic decompression (IED) versus conventional microsurgical technique (CMT) in patients with lumbar spinal stenosis is scarce. We analyzed 88 patients (IED: 36/88, 40.9%; CMT: 52/88, 59.1%) presenting with lumbar central spinal stenosis between 2018–2020. Surgery-related (operation time, complications, time to hospital release (THR), ASA score, C-reactive protein (CRP), white blood cell count (WBC), side (unilateral/bilateral), patient-reported (ODI, NRS (leg-, back pain), eQ5D, COMI), and radiological (preoperative dural sack cross-sectional area (DSCA), Shizas score (SC), left (LRH) and right (RRH) lateral recess heights, left (LFA) and right (RFA)
Trochlear geometry of modern femoral implants is designed for mechanical alignment (MA) technique for TKA. The biomechanical goal is to create a proximalised and more valgus trochlea to better capture the patella and optimize tracking. In contrast, Kinematic alignment (KA) technique for TKA respects the integrity of the soft tissue envelope and therefore aims to restore native articular surfaces, either femoro-tibial or femoro-patellar. Consequently, it is possible that current implant designs are not suitable for restoring patient specific trochlea anatomy when they are implanted using the kinematic technique, this could cause patellar complications, either anterior knee pain, instability or accelerated wear or loosening. The aim of our study is therefore to explore the extent to which native trochlear geometry is restored when the Persona. ®. implant (Zimmer, Warsaw, USA) is kinematically aligned. A retrospective study of a cohort of 15 patients with KA-TKA was performed with the Persona. ®. prosthesis (Zimmer, Warsaw, USA). Preoperative knee MRIs and postoperative knee CTs were segmented to create 3D femoral models. MRI and CT segmentation used Materialise Mimics and Acrobot Modeller software, respectively. Persona. ®. implants were laser scanned to generate 3D implant models. Those implant models have been overlaid on the 3D femoral implant model (generated via segmentation of postoperative CTs) to replicate, in silico, the alignment of the implant on the post-operative bone and to reproduce in the computer models the features of the implant lost due to CT metal artefacts. 3D models generated from post-operative CT and pre-operative MRI were registered to the same coordinate geometry. A custom written planner was used to align the implant, as located on the CT, onto the pre-operative MRI based model. In house software enabled a comparison of trochlea parameters between the native trochlea and the performed prosthetic trochlea. Parameters assessed included 3D trochlear axis and anteroposterior offset from medial
BACKGROUND. Trochlear geometry of modern femoral implants is designed for the mechanical alignment (MA) technique for Total Knee Arthroplasty (TKA). The biomechanical goal is to create a proximalised and more valgus trochlea to better capture the patella and optimize tracking. In contrast, Kinematic alignment (KA) technique for TKA respects the integrity of the soft tissue envelope and therefore aims to restore native articular surfaces, either femoro-tibial or femoro-patellar. Consequently, it is possible that current implant designs are not suitable for restoring patient specific trochlea anatomy when they are implanted using the kinematic technique. This could cause patellar complications, either anterior knee pain, instability or accelerated wear or loosening. The aim of our study is therefore to explore the extent to which native trochlear geometry is restored when the Persona. ®. implant (Zimmer, Warsaw, USA) is kinematically aligned. METHODS. A retrospective study of a cohort of 15 patients with KA-TKA was performed with the Persona. ®. prosthesis (Zimmer, Warsaw, USA). Preoperative knee MRIs and postoperative knee CTs were segmented to create 3D femoral models. MRI and CT segmentation used Materialise Mimics® and Acrobot Modeller® software, respectively. Persona. ®. implants were laser-scanned to generate 3D implant models. Those implant models have been overlaid on the 3D femoral implant model (generated via segmentation of postoperative CTs) to replicate, in silico, the alignment of the implant on the post-operative bone and to reproduce in the computer models the features of the implant lost due to CT metal artefacts. 3D models generated from post-operative CT and pre-operative MRI were registered to the same coordinate geometry. A custom written planner was used to align the implant, as located on the CT, onto the pre-operative MRI based model (figure 1). In house software enabled a comparison of trochlea parameters between the native trochlea and the performed prosthetic trochlea (figure 2). Parameters assessed included 3D trochlear axis and anteroposterior offset from medial
Purpose: Unrepairable fractures of the radial head are often treated with radial head arthroplasty. Insertion of a radial head prosthesis that is too thick, or overstuffed, is believed to be a common complication that may result in pain, arthrosis, capitellar wear and decreased elbow range of motion. The purpose of this study was to develop guidelines for determining the appropriate thickness of radial head implants. We hypothesized that. radiographic incongruity of the medial
Are there any patho-anatomical features that might predispose to primary knee OA? We investigated the 3D geometry of the load bearing zones of both distal femur and proximal tibias, in varus, straight and valgus knees. We then correlated these findings with the location of wear patches measured intra-operatively. Patients presenting with knee pain were recruited following ethics approval and consent. Hips, knees and ankles were CT-ed. Straight and Rosenburg weight bearing X-Rays were obtained. Excluded were: Ahlbäck grade “>1”, previous fractures, bone surgery, deformities, and any known secondary causes of OA. 72 knees were eligible. 3D models were constructed using Mimics (Materialise Inc, Belgium) and femurs oriented to a standard reference frame. Femoral condyle Extension Facets (EF) were outlined with the aid of gaussian curvature analysis, then best-fit spheres attached to the Extension, as well as Flexion Facets(FF). Resected tibial plateaus from surgery were collected and photographed, and Matlab combined the average tibia plateau wear pattern. Of the 72 knees (N=72), the mean age was 58, SD=11. 38 were male and 34 female. The average hip-knee-ankle (HKA) angle was 1° varus (SD=4°). Knees were assigned into three groups: valgus, straight or varus based on HKA angle. Root Mean Square (RMS) errors of the medial and lateral extension spheres were 0.4mm and 0.2mm respectively. EF sphere radii measurements were validated with Bland-Altman Plots showing good intra- and interobserver reliability (+/− 1.96 SD). The radii (mm) of the extension spheres were standardised to the medial FF sphere. Radii for the standardised medial EF sphere were as follows; Valgus (M=44.74mm, SD=7.89, n=11), Straight (M=44.63mm, SD=7.23, n=38), Varus (M=50.46mm, SD=8.14, n=23). Ratios of the Medial: Lateral EF Spheres were calculated for the three groups: Valgus (M=1.35, SD=.25, n=11), Straight (M=1.38, SD=.23, n=38), Varus (M=1.6, SD=.38, n=23). Data was analysed with a MANOVA, ANOVA and Fisher's pairwise LSD in SPSS ver 22, reducing the chance of type 1 error. The varus knees extension
The aim of the study was to assess the safety of a novel anatomical landmark in the placement of thoracic pedicle screws. It is our clinical observation that the sagittal plane of the screw trajectory is perpendicular to the plane of the superior articular
Aims. To develop a core outcome set of measurements from postoperative radiographs that can be used to assess technical skill in performing dynamic hip screw (DHS) and hemiarthroplasty, and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. A Delphi exercise was undertaken at a regional major trauma centre to identify candidate measurement items. The feasibility of taking these measurements was tested by two of the authors (HKJ, GTRP). Validity and reliability were examined using the radiographs of operations performed by orthopaedic resident participants (n = 28) of a multicentre randomized controlled educational trial (ISRCTN20431944). Trainees were divided into novice and intermediate groups, defined as having performed < ten or ≥ ten cases each for DHS and hemiarthroplasty at baseline. The procedure-based assessment (PBA) global rating score was assumed as the gold standard assessment for the purposes of concurrent validity. Intra- and inter-rater reliability testing were performed on a random subset of 25 cases. Results. In total, 327 DHS and 248 hemiarthroplasty procedures were performed by 28 postgraduate year (PGY) 3 to 5 orthopaedic trainees during the 2014 to 2015 surgical training year at nine NHS hospitals in the West Midlands, UK. Overall, 109 PBAs were completed for DHS and 80 for hemiarthroplasty. Expert consensus identified four ‘final product analysis’ (FPA) radiological parameters of technical success for DHS: tip-apex distance (TAD); lag screw position in the femoral head; flushness of the plate against the lateral femoral cortex; and eight-cortex hold of the plate screws. Three parameters were identified for hemiarthroplasty: leg length discrepancy; femoral stem alignment; and femoral offset. Face validity, content validity, and feasibility were excellent. For all measurements, performance was better in the intermediate compared with the novice group, and this was statistically significant for TAD (p < 0.001) and femoral stem alignment (p = 0.023). Concurrent validity was poor when measured against global PBA score. This may be explained by the fact that they are measuring difference
To investigate whether there are different patterns of patellar degeneration, 123 consecutive knee arthroplasties were investigated. Knees on which previous patellar surgery or osteotomies had been done were excluded. Areas of grade-III or more degeneration of the patella and femoral condyle were recorded. The femur was divided into three condyles and nine areas. The patella was divided into three
When navigating patellofemoral/unicompartmental knee surgery, the surgeon makes assumptions based upon algorithms developed for total knee arthroplasty. In this study we set out to show how variable the normal knee is. Minor anatomical variations in the shape of our knee may make a big difference in terms of orientation and joint wear patterns. Tibial patho-morphology has been described as a factor that predisposes to medial compartment osteoarthritis of the knee (anteromedial-OA), yet this is limited to 2D analysis. We aimed to describe the 3D morphology of both the tibial and femoral components of the medial compartment of the knee. We hypothesized that morphological differences do exist between normal knees and those predisposed to osteoarthritis. A total of 20 normal (group A) and 20 pre-OA knees (group B) were included. Group A consisted of contra lateral knees of young patients (<
55 years) awaiting hip surgery and group B of asymptomatic contra lateral knees of patients awaiting unicompartmental knee arthroplasty (UKA). Using 3D reconstructions from CT scans, we analyzed the tibiofemoral joint, which consists of the femoral condyles and the tibial plateau. The femur was aligned to the transcondylar and anatomical axes. The medial femoral extension
During knee arthroplasty operations, it appeared that different patterns of patellar degeneration occur. To confirm this, 123 patellae were evaluated in a prospective study. The patellae of patients who had undergone patellar surgery or osteotomy were excluded. The femur was divided into three condyles and nine areas, and the patella into three
Summary Statement. Spinal flexibility in bending and axial torque has been shown to exhibit very modest changes with advancing disc degeneration. This study is the first to address the possible relationship in pure anterior shear and no clear relationship was observed. Introduction. Disc degeneration (DD) is a risk factor for low back pain. Stable or unstable spine segments may be treated with an isolated decompression or instrumented stabilization, respectively. The effect of DD on spinal flexibility has been addressed by several groups in bending but not in shear; a highly relevant load direction in the lumbar spine is anterior shear. The objective of our study was to determine the effect of DD on anterior translation and specimen stiffness under shear loading in an in vitro model of degenerative spondylolisthesis. Methods. Magnetic resonance images were obtained for human cadaveric lumbar FSUs (N=30). Disc degeneration was assessed with the Pfirrmann five-point grading scale. Three surgeons independently graded the discs and the grade common to at least two of the surgeons was assigned to that specimen. Each specimen was then tested in three sequential states: intact,
Introduction:. Varus alignment of the knee is common in patients undergoing unicondylar knee replacement. To measure the geometry and morphology of these knees is to know whether a single unicondylar knee implant design is suitable for all patients, i.e. for patients with varus deformity and those without. The aim of this study was to identify any significant differences between normal and varus knees that may influence unicondylar implant design for the latter group. Methodology:. 56 patients (31 varus, 25 normal) were evaluated through CT imaging. Images were segmented to create 3D models and aligned to a tri-spherical plane (centres of spheres fitted to the femoral head and the medial and lateral flexion facets). 30 key co-ordinates were recorded per specimen to define the important axes, angles and shapes (e.g. spheres to define flexion and extension
The most common injury in rugby resulting in
spinal cord injury (SCI) is cervical
Abstract. Objectives. Catastrophic neck injuries in rugby tackling are rare (2 per 100,000 players per year) with 38% of these injuries occurring in the tackle. The aim of this study was to determine the primary mechanism of cervical spine injury during rugby tackling and to highlight the effect of tackling technique on intervertebral joint loads. Methods. In vivo and in vitro experimental data were integrated to generate realistic computer simulations representative of misdirected tackles. MRI images were used to inform the creation of a musculoskeletal model. In vivo kinematics and neck muscle excitations were collected during lab-based staged tackling of the player. Impact forces were collected in vitro using an instrumented anthropometric test device during experimental simulations of rugby collisions. Experimental kinematics and muscle excitations were prescribed to the model and impact forces applied to seven skull locations (three cranial and four lateral). To examine the effects of technique on intervertebral joint loads the model's neck angle was altered in steps of 5° about each rotational axis resulting in a total of 1,623 experimentally informed simulations of misdirected tackles. Results. Neck flexion angles and cranial impact locations had the largest effects on maximal compression, anterior shear and flexion moment loads. During posterior cranial impacts compression forces and flexion moments increased from 1500 to 3200 N and 30 to 60 Nm respectively between neck angles of 30° extension and 30° flexion. This was more evident at the C5-C6 and C6-C7 joints. Anterior shear loads remained stable throughout neck angle ranges however during anterior impacts they were directed posteriorly when the neck was flexed. Conclusions. The combination of estimated joint loads in the lower cervical spine support buckling as the primary injury mechanism of anterior bilateral
Purpose: At present there is no reported, valid and reproducible model of degenerative spondylolisthesis for biomechanical testing of spinal implants. The purpose of this study was to create a single functional spinal unit (FSU) model that could demonstrate anterolisthesis consistent with low grade degenerative spondylolisthesis under physiologic shear loads. Method: Eight fresh-frozen human cadaveric, lumbar FSU’s were potted and secured in a custom jig for pure shear testing. The cranial segment was loaded from – 50N (posterior) to 250N (anterior) over three cycles for each of five test conditions with a 300N preload. Test conditions addressed known restraints to shear translation and were performed in the same order for all specimens, and included: intact,
Background: The Evans osteotomy has been proven to be very effective in treating flatfoot deformity in adults. However, it has not been shown whether the site of osteotomy influences the contact areas and peak pressures within the subtalar joint. It is hypothesized that the posterior
Purpose of the study: In accordance with the conclusions established at the SOFCOT symposium in 1988, we propose surgical treatment of displaced fractures of the calcaneus with screw fixation after reduction. We developed an original classification system of 3D computed tomography images which allows a precise description of the fractures and guides joint and calcaneal body reconstructions. The purpose of this work was to provide a precise analysis of operated fractures in order to identify prognostic factors and validate use of exclusive screw fixation for calcaneal fractures. Materials and methods: This series included 60 operated articular fractures of the calcaneus. The Uthéza classification was: 12 vertical, 7 horizontal with 1 fracture line, 3 horizontal with 2 fracture lines, 23 mixed with 1 fracture line and 15 mixed with 2 fracture lines. 3D computed tomography evidenced the fundamental fracture lines and their anterior extension. Fixation was achieved with one screw inserted in a transverse position under the posterior
Purpose And Background: In patients with chronic low back pain (LBP), selective injection procedures (provocative discography, medial branch,
The purpose of our study is to assess the degenerative changes in the motion segments above a L5S1 spondylolytic spondylolisthesis, and to analyse the factors that contribute towards a retro-listhesis in the segment immediately above the slip. Prospective radiographic case series. 38 patients with a symptomatic L5S1 spondylolytic spondylolisthesis, with a mean age of 52.8 yrs (95% CI 47.2 – 58.4). 55.3% (n = 21) were females and 44.7% (n = 17) males. 58% (22) had grade 1 and 42% (16) grade 2 slips. Plain radiographs: Lumbar lordosis, slip angle, sacral slope, grade of the slip, and retro-listhesis at L45. MRI scans:
Introduction:. The insertion footprint of the different muscles tendon fascicles of the Achilles Tendon on the calcanium tuberosity has not been described before. Method:. Twelve fresh frozen leg specimens were dissected to identify the different Achilles Tendon fascicles insertion footprint on the calcaneum in relation to their corresponding muscles. Further ten embalmed cadaveric leg specimens were examined to confirm an observation on the retrocalcaneal bursa. Results:. The superficial part of the AT insertion is made by tendon fascicles from the medial head of the gastrocnemius muscle which insert over the entire width of the inferior
The total disc replacement (TDR) devices are gaining popularity because of their capability of allowing joint motion at the index level. Studies have shown that motion preservation can reduce the likelihood of further degeneration at the adjacent level with better surgical outcome. Current lumbar TDR devices require an anterior approach for implantation. However, it is known that its clinical outcome may depend on implant insertion and placement during surgery. Only limited number of biomechanical studies regarding the effect of placement orientation on the clinical outcome is currently available. The purpose of this study was to investigate effects of various surgical placement of a lumbar TDR on the kinematics and load-sharing characteristics using finite element method (FEM). A previously-validated 3-D nonlinear FE model of the intact lumbar motion segment (L3-S1) based on computer tomography (CT) images of a cadaveric specimen (male, age 56, no pathologies) was used as the baseline FE model. Then, implantation of ProDisc-L (Spine Solutions, Inc., Synthes, Paoli, PA, USA) was simulated into the L4–L5 disc space through anterior approach with removal of the nucleus, anterior longitudinal ligament, and the anterior part of the annulus. The location of lumbar TDR was varied in the sagittal and the coronal planes. In the sagittal plane, the implants were placed anteriorly at 3-mm (S-3), 5-mm (S-5), and 7-mm (S-7) offset from the posterior margin of the endplate. In the coronal plane, the devices were shifted from the baseline position laterally to the right by 1-mm (C-1), 2-mm (C-2), and 3-mm (C-3) from the mid-sagittal line along the lower endplate. All of the models were subject to 150N compressive pre-load and flexion/extension moments of 10Nm at the superior endplate L4, while the inferior endplate of L5 was fully constrained. Changes in motion (ROM) and
The rotator cuff is sited on the anatomical neck of the humerus and is formed by the insertion of the supraspinatus (SP), infraspinatus (IS), teres minor (TM) and subscapularis. All play a vital role in the movement of the glenohumeral joint, and the anatomy is of critical importance in arthroscopic rotator cuff repair. We undertook an osteological and gross anatomical dissection study of the insertion mechanism of these tendons, in particular the SP . The SP inserts by a triple or quadruple mechanism. The ‘heel’ (medial) and capsule fuse, inserting into the anatomical neck proximal to the anterior
1. During a fifteen-year period a clinical, radiological and in some cases a surgical study has been made of 319 patients suffering from spondylolisthesis–that is, forward slipping of one lumbar vertebra on another or forward sagging of the whole lumbar spine in relation to the sacrum. 2. The five etiological factors are described, and the cases are assigned to five groups according to the factor responsible for the slip. In every case slipping is permitted by a lesion of the apparatus which normally resists the forward thrust of the lower lumbar spine–that is, the hook of the neural arch composed of the pedicle, the pars interarticularis and the inferior articular
We have studied fracture-dislocation of the fifth lumbar vertebra in seven patients and reviewed 50 previously reported cases. Based on this information, we have classified the injury into five types: type 1, unilateral lumbosacral facet-dislocation with or without
Background: Calcaneonavicular coalitions (CNC) have been reported to be associated with anatomical aberrations of either the calcaneus and/or navicular bones. These morphological abnormalities may complicate accurate surgical resection. Three-dimensional analysis of spatial orientation and morphological characteristics may help in preoperative planning of resection. Materials and Methods: Sixteen feet diagnosed with CNC were evaluated by means of 3D CT modeling. Three angles were defined that were expressed in relation to one reproducible landmark (lateral border of the calcaneus): the dorsoplantar inclination, anteroposterior inclination and socket angle. The contact surface area was determined from the depth and width of the coalitions. Three-dimensional reconstructions of the calcanei evaluated the presence and morphology of the anterior calcaneal
In six unloaded cadaver knees we used MRI to determine the shapes of the articular surfaces and their relative movements. These were confirmed by dissection. Medially, the femoral condyle in sagittal section is composed of the arcs of two circles and that of the tibia of two angled flats. The anterior
Cadaver knee joints were mounted so that life-like forces of weight-bearing were simulated. The patello-femoral contact areas were defined under load throughout the range of movement by the dye method. During movement from extension to 90 degrees of flexion a band of contact sweeps across the patella from inferior to superior pole, but the odd