This study aimed to examine the effect of high tibial osteotomy (HTO) on the ankle and subtalar joints via analysis of static radiographic alignment. We hypothesised that surgical alteration of the alignment of the proximal tibia would result in compensatory distal changes. 35 patients recruited as part of the wider Biomechanics and Bioengineering Centre Versus Arthritis HTO study between 2011 and 2018 had pre- and postoperative full-length weightbearing radiographs taken of their lower limbs. In addition to standard alignment measures of the limb and knee (mechanical tibiofemoral angle, Mikulicz point, medial proximal tibial angle), additional measures were taken of the ankle/subtalar joints (lateral distal tibial angle, ground-talus angle, joint line convergence angle of the ankle) as well as a novel measure of stance width. Results were compared using a
Introduction. Knee dislocations, vascular injuries and floating knee injuries can be initially managed by a external fixator. Fixator design constructs include the AO pattern and the Diamond pattern. However, these traditional constructs do not adhere to basic principles of external fixation. The Manchester pattern knee-spanning external fixator is a new construct pattern, which uses beam loading and multiplanar fixation. There is no data on any construct pattern. This study compares the stability of these designs. Materials & Methods. Hoffman III (Stryker, USA) external fixation constructs were applied to articulated models of the lower limb, spanning the knee with a diamond pattern and a Manchester pattern. The stiffness was loaded both statically and cyclically with a Bose 3510 Electroforce mechanical testing jig (TA Instruments). A ramp to load test was performed initially and cyclical loading for measurement of stiffness over the test period. The results were analysed with a
Progressive collapsing foot deformity (PCFD) is a complex foot deformity with varying degrees of hindfoot valgus, forefoot abduction, forefoot varus, and collapse or hypermobility of the medial column. In its management, muscle and tendon balancing are important to address the deformity. Peroneus brevis is the primary evertor of the foot, and the strongest antagonist to the tibialis posterior. Moreover, peroneus longus is an important stabilizer of the medial column. To our knowledge, the role of peroneus brevis to peroneus longus tendon transfer in cases of PCFD has not been reported. This study evaluates patient reported outcomes including pain scores and any associated surgical complications for patients with PCFD undergoing isolated peroneus brevis to longus tendon transfer and gastrocnemius recession. Patients with symptomatic PCFD who had failed non-operative treatment, and underwent isolated soft tissue correction with peroneus brevis to longus tendon transfer and gastrocnemius recession were included. Procedures were performed by a single surgeon at a large University affiliated teaching hospital between January 1 2016 to March 31 2021. Patients younger than 18 years old, or undergoing surgical correction for PCFD which included osseous correction were excluded. Patient demographics, medical comorbidities, procedures performed, and pre and post-operative patient related outcomes were collected via medical chart review and using the appropriate questionnaires. Outcomes assessed included Visual Analogue Scale (VAS) for foot and ankle pain as well as sinus tarsi pain (0-10), patient reported outcomes on EQ-5D, and documented complications. Statistical analysis was utilized to report change in VAS and EQ-5D outcomes using a
Distal radius fracture is one of the most common fractures in older women (∼70,000 cases annually in Canada). Treatment of this fracture has been shifting toward surgery (mainly volar locking plate (VLP) technology), which significantly enhances surgeon's ability to maintain correction. However, current surgical outcomes are far from perfect. There is a need for an implant which maintains the corrected position (reduction), minimizes soft tissue disruption, and is technically easy to perform. A novel internal, composite-based implant was designed to achieve these ends. It is unclear, however, whether this novel implant offers similar fracture fixation as the VLP. As such, the objective of this research was to evaluate the fracture stability (assessed by calculating change in fracture length) of the novel implant and VLP under cyclic fatigue loading. Specimens: Seven radius specimens derived from older female cadavers (mean = 82.3 years, SD = 11.3 years) were used for the experiment. Preparation: A standardized dorsal wedge was removed from the cortex. The distance from the proximal and distal transverse osteotomies was 10 mm and was positioned 20 mm proximal to the tip of the radial styloid. The osteotomy removed all load-bearing capabilities of bone, equivalent to a worst-case-scenario for DRF fixation. Simulated Loading: The proximal end of the radii was potted (fixed) and positioned in a material testing system. To mimic natural loading conditions, hands were cycled between −30°/30° flexion/extension, at 0.5 Hz, for 2000 cycles, while tension load was applied to the tendons (25-N constant force per tendon, 100-N in total). Mechanical testing outcomes: A position tracking sensor used to measure change in fracture length. This change, as a function of number of cycles, was used to assess implant resistance to fatigue loading. Statistical Analysis: A
Introduction. Circumferential periosteal release is a rarely reported procedure for paediatric limb lengthening. The technique involves circumferential excision of a strip of periosteum from the metaphysis of the distal femur, tibia and fibula. This study aims to determine the mid to long-term effectiveness of this technique. Materials and Methods. A retrospective case series was performed of all patients undergoing circumferential periosteal release of the distal femur and/or tibia between 2006 and 2017. Data collected included demographics, surgical indication, post-operative limb-lengths and complications. Data collection was stopped if a further procedure was performed that may affect limb-length (except a further release). Leg-length discrepancies were calculated as absolute values and as percentages of the longer limb-length. Final absolute and percentage discrepancies were compared to initial discrepancies using a
This study was designed to compare atypical hip fractures with a matched cohort of standard hip fractures to evaluate the difference in outcomes. Patients from the American College of Surgeons National Surgical Quality Improvement Program's (NSQIP) targeted hip fracture data file (containing a more comprehensive set of variables collected on 9,390 specially targeted hip fracture patients, including the differentiation of atypical from standard hip fractures) were merged with the standard 2016 NSQIP data file. Atypical hip fracture patients aged 18 years and older in 2016 were identified via the targeted hip fracture data file and matched to two standard hip fracture controls by age, sex, and fracture location. Patient demographics, length of hospital stay, 30-day mortality, major and minor complications, and other hip-specific variables were identified from the database. Binary outcomes were compared using the McNemar's test for paired groups, and continuous outcomes were compared using a
BACKGROUND:. Although most radiographs used for polyethylene wear measurements have been taken with the patient in the supine position in order to assess penetration by the femoral head into the acetabular polyethylene socket, we have questioned the effect of weight-bearing on the position of the head within the socket. The current study aimed to determine the effect of weight bearing, i.e. standing on the two-dimensional radiographic position of the femoral head within the socket. PATIENTS AND METHODS:. A total of three hundred and fifty patients (three hundred and eighty three hips) who had had a total hip arthroplasty had digital radiographs made a set of anteroposterior radiographs for each patient: one radiograph was made with the patient supine and one was made with the patient standing in full weight bearing on the replaced hip. The patients were divided into the following two groups: 1) seventy-five patients (eighty-three hips) with conventional polyethylene (CON) (group-1); 2) two hundred and seventy-five patients (three hundred hips) with highly cross-linked polyethylene (XPL) (group-2). The set of radiograph was taken at three weeks postoperatively and at the time of semiannual follow-up. The average ceramic femoral head penetration was measured with radiographs taken in the standing or supine position at the final follow-up and compared with those of three weeks postoperatively. A single researcher with use of a computerized measurement system performed all measurements on the radiographs of the two-dimensional position of the head. Follow-up period were 13.5 ± 1.0 (range. 11.0–15.5) years in group-1 and 7.6 ± 2.1 (range. 5.0–12.6) years in group-2. RESULTS:. Linear penetration rates in group-1 were 0.172 ± 0.069 mm/year in supine position and 0.178 ± 0.069 mm/year in standing position (p < 0.05,
The opposable thumb is one of the defining characteristics of human anatomy and is involved in most activities of daily life. Lack of optimal thumb motion results in pain, weakness, and decrease in quality of life. First carpometacarpal (CMC1) osteoarthritis (OA) is one of the most common sites of OA. Current clinical diagnosis and monitoring of CMC1 OA disease are primarily aided by X-ray radiography; however, many studies have reported discrepancies between radiographic evidence of CMC1 OA and patient-related outcomes of pain and disability. Radiographs lack soft-tissue contrast and are insufficient for the detection of early characteristics of OA such as synovitis, which play a key role in CMC OA disease progression. Magnetic resonance imaging (MRI) and two-dimensional ultrasound (2D-US) are alternative options that are excellent for imaging soft tissue pathology. However, MRI has high operating costs and long wait-times, while 2D-US is highly operator dependent and provides 2D images of 3D anatomical structures. Three-dimensional ultrasound imaging may be an option to address the clinical need for a rapid and safe point of care imaging device. The purpose of this research project is to validate the use of mechanically translated 3D-US in CMC OA patients to assess the measurement capabilities of the device in a clinically diverse population in comparison to MRI. Four CMC1-OA patients were scanned using the 3D-US device, which was attached to a Canon Aplio i700 US machine with a 14L5 linear transducer with a 10MHz operating frequency and 58mm. Complimentary MR images were acquired using a 3.0 T MRI system and LT 3D coronal photon dense cube fat suppression sequence was used. The volume of the synovium was segmented from both 3D-US and MR images by two raters and the measured volumes were compared to find volume percent differences. Paired sample t-test were used to determine any statistically significant differences between the volumetric measurements observed by the raters and in the measurements found using MRI vs. 3D-US. Interclass Correlation Coefficients were used to determine inter- and intra-rater reliability. The mean volume percent difference observed between the two raters for the 3D-US and MRI acquired synovial volumes was 1.77% and 4.76%, respectively. The smallest percent difference in volume found between raters was 0.91% and was from an MR image. A
Rotator cuff tears are the most common cause of shoulder disability, affecting 10% of the population under 60 and 40% of those aged 70 and above. Massive irreparable rotator cuff tears account for 30% of all tears and their management continues to be an orthopaedic challenge. Traditional surgical techniques, that is, tendon transfers are performed to restore shoulder motion, however, they result in varying outcomes of stability and complications. Superior capsular reconstruction (SCR) is a novel technique that has shown promise in restoring shoulder function, albeit in limited studies. To date, there has been no biomechanical comparison between these techniques. This study aims to compare three surgical techniques (SCR, latissimus dorsi tendon transfer and lower trapezius tendon transfer) for irreparable rotator cuff tears with respect to intact cuff control using a clinically relevant biomechanical outcome of rotational motion. Eight fresh-frozen shoulder specimens with intact rotator cuffs were tested. After dissection of subcutaneous tissue and muscles, each specimen was mounted on a custom shoulder testing apparatus and physiologic loads were applied using a pulley setup. Under 2.2 Nm torque loading maximum internal and external rotation was measured at 0 and 60 degrees of glenohumeral abduction. Repeat testing was conducted after the creation of the cuff tear and subsequent to the three repair techniques. Repeated measures analysis with
INTRODUCTION. In patients presenting with significant ligamentous instability/insufficiency and/or significant varus/valgus deformity of the knee, reproduction of knee alignment and soft tissue stability continues to be a difficult task to achieve. These complex primary total knee arthroplasty (TKA) candidates generally require TKA systems incorporating increasing levels of constraint due to the soft-tissue and/or bone deficiencies. In addition, achievement of “normal” gap symmetry through physiologic kinematics is challenging due to the complexity of the overall correction. Advancements in TKA design have not fully addressed the negative consequences of the increased forces between the degree of component constraint, the femoral box, and the tibial post. The purpose of this early feasibility study was to introduce the design characteristics of a primary TKA system that incorporates progressive constraint kinematics using a low profile trapezoidal femoral box, and to assess the short-term clinical and radiographic results of this patient cohort. METHODS. We retrospectively evaluated 22 consecutive, non-selected, complex primary TKA patients with a minimum of 3-years follow-up and varus deformity of > 20 degrees or valgus deformity of >15 degrees. The Progressive Constraint Kinematics® Knee System (PCK, MAXX Orthopedics, Norristown, PA) was used and provides a variable constraint profile, from high constraint in extension to less constraint in flexion through a novel trapezoidal femoral box. We evaluated patient demographics, pre- and post-operative serial radiography, range of motion (ROM), and total Knee Society Score (KSS – total score). General descriptive statistics and
INTRODUCTION. The specific factors affecting wear of the ultrahigh molecular weight polyethylene (UHMWPE) tibial component of total knee replacements (TKR) are poorly understood. One recent study demonstrated that lower conforming inserts produced less wear in knee simulators. The purpose of this study is to investigate the effect of insert conformity and design on articular surface wear of postmortem retrieved UHMWPE tibial inserts. METHODS. Nineteen NexGen cruciate-retaining (NexGen CR) and twenty-five NexGen posterior-stabilized (NexGen PS) (Zimmer) UHWMPE tibial inserts were retrieved at postmortem from fifteen and eighteen patients respectively. Articular surfaces were scanned at 100×100μm using a coordinate measuring machine (SmartScope, OGP Inc.). Autonomous mathematical reconstruction of the original surface was used to calculate volume loss and linear penetration maps of the medial and lateral plateaus. Wear rates for the medial, lateral and total articular surface were calculated as the slope of the linear regression line of volume loss against implantation time. Volume loss due to creep was estimated as the regression intercept. Student t-tests were used to check for significant. RESULTS. The NexGen CR and NexGen PS patient groups were approximately the same age at time of implantation (mean±SD: 72.1±9.9 and 68.7±8.8 years respectively, p=0.260) and implantation times were not significantly different (8.7±3.1 and 9.1±3.7 years, p=0.670). Both groups showed high variability in wear scars. No significant difference in wear rates on the total surface (mean±SE: 11.89±5.01 mm. 3. /year vs. 11.09±4.18 mm. 3. /year, p=0.905). However, NexGen CR components showed significantly higher volume loss due to creep than NexGen PS components (70.22±47.07 mm. 3. vs. 31.30±41.15 mm. 3. , p=0.007). These results were reflected on the medial and lateral sides, with no significant differences in wear rates on the medial side (p=0.856) or lateral side (p=0.633) and higher volume losses due to creep associated with the NexGen CR components. While NexGen CR and NexGen PS showed a near equal mean percentage of volume loss on the medial side (CR: 52.4±11.7%, PS: 52.5±11.6%), a
Computer assisted total knee arthroplasty helps in accurate and reproducible implant positioning, bony alignment, and soft-tissue balancing which are important for the success of the procedure. In TKR, there are two surgical techniques one is measured resection in which bony landmarks are used to guide the bone cuts and the other is gap balancing which equal collateral ligament tension in flexion and extension is done before and as a guide to final bone cuts. Both these procedures have their own advantages and disadvantages. We retrospectively collected the data of 128 consecutive patients who underwent computer-assisted primary TKA using either a gap-balancing technique or measured resection technique. All the operations were performed by a single surgeon using computer navigation system available during a period between June 2016 to October 2016. Inclusion criteria were all patients requiring a primary TKA, male or female patients, and who have given informed consent for participation in the study. All patients requiring revision surgery of a previous implanted TKA or affected by active infection or malignancy, who presented hip ankylosis or arthrodesis, neurological deficit or bone loss or necessity of more constrained implants were excluded from the study. Two groups measured resection and gap balancing was randomly selected. At 1-year follow-up, patients were assessed by a single orthopaedic registrar blinded to the type of surgery using the Knee Society score (KSS) and functional Knee Society score (FKSS). Outcomes of the 2 groups were compared using the paired t test. All the obtained data were analysed. Statistical analysis was performed using SPSS 11.5 statistical software (SPSS Inc. Chicago). Inter-class correlation coefficient (ICC) and
Introduction. Modified gap technique has been reported to be beneficial for the intraoperative soft tissue balancing in posterior-stabilized (PS) -TKA. We have found intraoperative ligament balance changed depending on joint distraction force, which might be controlled according to surgeons' fells. We have developed a new surgical concept named as “medial preserving gap technique (MPGT)” to preserve medial knee stability and provide quantitative surgical technique according to soft tissue balance measurement using a tensor device. The purpose of this study was to compare 3-years postoperative knee stability after PS-TKA in varus type osteoarthritic (OA) knees between MPGT and measured resection technique (MRT). Material & Method. The subjects were 94 patients underwent primary unilateral PS-TKA for varus type OA knees. The surgical technique was MPGT in 47 patients and MRT in 47 patients. An originally developed off-set type tensor device was used to evaluate intraoperative soft tissue balance. In MPGT, medial release was limited until the spacer block corresponding to the bone thickness from proximal lateral tibial plateau could be easily inserted. Femoral component size and external rotation angle were adjusted depending on the differences of center gaps and varus angles between extension and flexion before posterior femoral condylar resection. The knee stabilities at extension and flexion were assessed by stress radiographies at 1 and 3 years after TKA; varus-valgus stress test at extension and stress epicondylar view at flexion. We measured medial and lateral joint openings (MJO, LJO) at both knee extension and flexion. MJOs and LJOs at 2 time periods were compared in each group using
Introduction. For restoration of neutral limb alignment in Total Knee Arthroplasty (TKA), we usually start by removing osteophytes in varus osteoarthritic knees. However, we have found no reports in the literature regarding research on the exact influence of osteophyte removal on angle correction. The purpose of this study was to define the influence of osteophyte removal on limb alignment correction in the coronal plane in TKA. Materials and Methods. Nine patients with varus malalignment that were scheduled for TKA were included in this study. Only patients with degenerative osteoarthritis were considered. After registration of a navigation system, each knee was tested at maximum extension, and 30 and 60 degrees of flexion before and after osteophyte removal. The same examiner applied all external loads of 10 N-m valgus torque at each angle and in both states. Subsequently, the widths of the osteophytes were measured. All data were analyzed statistically using
The objectives of this study are to ascertain primary caregivers' understanding of risks associated with home trampoline use; to educate caregivers in regard to documented literature based risks associated with home trampoline use; and to evaluate if this information will have any influence on their future regulation of home trampoline use for their children. One hundred primary caregivers of patients treated in the paediatric orthopaedic surgery outpatient clinic at London Health Sciences centre were surveyed. All caregivers in clinic were invited to participate. The only exclusion criteria was the inability to provide consent. Caregivers' baseline perceptions on the risks associated with home trampoline use were assessed using a questionnaire. Caregivers then received an information pamphlet outlining documented trampoline safety data. They were then sent the same questionnaire to complete within one week of reading the pamphlet. Using our research electronic database capture (Redcap), the results of the surveys were compiled and analysed using spss 22,
Objectives. The purpose of this study was to evaluate the impact of multi-radius (MR, n=20) versus gradually reducing radius (GR, n=18) knee design on the kinematics and kinetics of the knee during level ground walking one year after total knee arthroplasty. Materials and Methods. Thirty-eight knees with end-stage knee osteoarthritis were examined before and one year after total knee arthroplasty. The groups consisted of subjects who had undergone total knee arthroplasty with a representative MR designed implant (B Braun-Aesculap Vega. ®. Knee System) and a representative GR designed implant (Depuy Attune. ®. Knee System) (Figure 1). The kinematic and kinetic parameters of knee varus angle, first peak knee adduction moment, sagittal plane knee excursion and extensor moment were evaluated during gait, as well as the spatiotemporal gait outcomes of walking speed, stride length, cadence, step length, the percentage of stance phase. Comparisons of preoperative and postoperative outcomes were done by the
Fixation of tendon transfers about the foot in children typically involves creating a bone tunnel through which a suture is passed and tied over an external button. An internal suspension system, such as the Endobutton (Smith & Nephew) is an alternative fixation method which has demonstrated excellent fixation strength and minimal intraosseous tunnel displacement in various adult procedures. Application of the Endobutton technique has no risk of skin ulceration, does not require suture removal and may provide more secure fixation. The purpose of this study is to compare the biomechanical properties of the external button and Endobutton fixation techniques. Our primary outcome measure was intra-osseous displacement of the suture, during both static and dynamic loading, in cadaver feet. Nine adult cadaver feet were utilised. A bone tunnel was drilled in the lateral cuneiform and #1 braided non-absorbable suture was passed through the tunnel. One end was secured to a carabiner to be attached to the materials testing system and the other to the fixation device. The external button and Endobutton fixation techniques were tested once in each cadaver, randomising the order of testing to minimise bias. Each fixation technique underwent static and dynamic cyclic loading. A custom Matlab script was used to process video and materials testing system data. The relative displacement of the suture within the bone tunnel, as a function of time and load magnitude, was recorded during static and dynamic cyclic loading. Both fixation groups were analysed and compared for statistical significance using a
The MediShoe (Promedics Orthopaedics Ltd, Glasgow) is a specific post-operative foot orthosis used by post-operative foot and ankle patients designed to protect fixations, wounds and maximise comfort. The use of rigid-soled shoes has been said to alter joint loading within the knee and with the popular use of the MediShoe at our centre in post operative foot and ankle surgery patients, it is important to ascertain whether this is also true. An analysis of the knee gait kinetics in healthy subjects wearing the MediShoe was carried out. Ten healthy subjects were investigated in a gait lab both during normal gait (control) and then with one shoe orthosis worn. Force plates and an optoelectronic motion capture system with retroreflective markers were used and placed on the subjects using a standardised referencing system. Three knee gait kinetic parameters were measured:- knee adduction moment; angle of action of the ground reaction force with respect to the ground in the coronal plane as well as the tibiofemoral angle. These were calculated with the Qualisys software package (Gothenburg, Sweden). A two-tailed
Introduction. The purpose of this study was to demonstrate the feasibility of passively collecting objective data from a commercially available smartphone-based care management platform (sbCMP) and robotic assisted total knee arthroplasty (raTKA). Methods. Secondary data analysis was performed using de-identified data from a commercial database that collected metrics from a sbCMP combined with intraoperative data collection from raTKA. Patients were included in this analysis if they underwent unilateral raTKA between July 2020 and February 2021, and were prescribed the sbCMP (n=131). The population consisted of 76 females and 55 males, with a mean age of 64 years (range, 43 – 81). Pre-operative through six-week post-operative data included step counts from the sbCMP, as well as administration of the KOOS JR. Intraoperative data included surgical times, the hip-knee-ankle angle (HKA), and medial and lateral laxity assessments from the robotic assessment. Data are presented using descriptive statistics. Comparisons were performed using a
Introduction. A stem extension improves fixation stability of a tibial component. We need caution not to contact the tibial cortex with an offset adaptor. A symmetric tibial stem design often requires the component's re-positioning with negative effects. Therefore, the objective of this study was to validate clinical efficacy of a tibial baseplate with asymmetric stemmed position (TB-ASP) using aligning outlier rate. We hypothesized that TB-ASP design will be better aligned without unessential offset adaptor than a tibial baseplate with symmetric stemmed position (TB-SSP). Methods. TB-ASP was designed based on the anthropometric standard model (58 female cadavers, 54.7±11.4 years)(Figure 1.). To validate the stem position, 3D bone models of 20 OA patients (71.8±7.2 years) was reconstructed. All virtual surgery has done by one surgeon with consistent surgical procedure for the analysis criteria. An analysis of TB-ASP's aligning outlier was proceeded by following steps; 1) aligning tibial baseplate to the line from medial 1/3 tuberosity to the center of PCL, 2) selecting tibial baseplate's size for maximal bone coverage without problematic overhang, 3) trying to displace tibial baseplate and stem extension(120mm long) not to contact tibial cortex. A case invading tibial cortex was considered to be an outlier. The ratio using offset adaptor was compared to those of TB-SSP. Statistical analysis was performed using