Methods. In this study of patients who underwent internal fixation without
fusion for a burst thoracolumbar or lumbar fracture, we compared
the serial changes in the injured disc height (DH), and the fractured
vertebral body height (VBH) and kyphotic angle between patients
in whom the implants were removed and those in whom they were not. Radiological
parameters such as injured DH, fractured VBH and kyphotic angle
were measured. Functional outcomes were evaluated using the Greenough
low back outcome scale and a VAS scale for pain. Results. Between June 1996 and May 2012, 69 patients were analysed retrospectively;
47 were included in the implant removal group and 22 in the implant
retention group. After a mean follow-up of 66 months (48 to 107),
eight patients (36.3%) in the implant retention group had screw
breakage. There was no
Aims. The aim of this study was to investigate the safety and efficacy of 3D-printed modular prostheses in patients who underwent joint-sparing limb salvage surgery (JSLSS) for malignant femoral diaphyseal bone tumours. Methods. We retrospectively reviewed 17 patients (13 males and four females) with femoral diaphyseal tumours who underwent JSLSS in our hospital. Results. In all, 17 patients with locally aggressive bone tumours (Enneking stage IIB) located in the femoral shaft underwent JSLSS and reconstruction with 3D-printed modular prostheses between January 2020 and June 2022. The median surgical time was 153 minutes (interquartile range (IQR) 117 to 248), and the median estimated blood loss was 200ml (IQR 125 to 400). Osteosarcoma was the most common pathological type (n = 12; 70.6%). The mean osteotomy length was 197.53 mm (SD 12.34), and the median follow-up was 25 months (IQR 19 to 38). Two patients experienced local recurrence and three developed distant metastases. Postoperative complications included wound infection in one patient and
Introduction. Pedicle
To evaluate the functional outcome of open humerus diaphyseal fractures treated with the Three-stitch technique of antegrade humerus nailing. This is a retrospective study conducted at the Department of Orthopaedics in D. Y. Patil University, School of Medicine, Navi Mumbai, India. The study included 25 patients who were operated on from January 2019 to April 2021 and follow-ups done till May 2022. Inclusion criteria were adult patients with open humerus diaphyseal fractures (Gustilo-Anderson Classification). All patients with closed fractures, skeletally immature patients, and patients with associated head injury were excluded from the study. All patients were operated on with a minimally invasive Three-stitch technique for antegrade humerus nailing. All patients were evaluated based on DASH score. Out of the 25 patients included in the study, all patients showed complete union. The mean age of the patients was 40.4 years (range 23–66 years). The average period for consolidation of fracture was 10.56 weeks (range 8–14 weeks). The DASH score ranged from 0 to 15.8 with an average score of 2.96. Five patients reported complications with three patients of post-operative infection and delayed wound healing and two patients with
Proximal humerus fractures are the third most common fragility fractures with treatment remaining challenging. Mechanical fixation failure rates of locked plating range up to 35%, with 80% of them being related to the screws perforating the glenohumeral joint. Secondary screw perforation is a complex and not yet fully understood process. Biomechanical testing and finite element (FE) analysis are expected to help understand the importance of various risk factors. Validated FE simulations could be used to predict perforation risk. This study aimed to (1) develop an experimental model for single screw perforation in the humeral head and (2) evaluate and compare the ability of bone density measures and FE simulations to predict the experimental findings. Screw perforation was investigated experimentally via quasi-static ramped compression testing of 20 cuboidal bone specimens at 1 mm/min. They were harvested from four fresh-frozen human cadaveric proximal humeri of elderly donors (aged 85 ± 5 years, f/m: 2/2), surrounded with cylindrical embedding and implanted with a single 3.5 mm locking screw (DePuy Synthes, Switzerland) centrally. Specimen-specific linear µFE (ParOSol, ETH Zurich) and nonlinear explicit µFE (Abaqus, SIMULIA, USA) models were generated at 38 µm and 76 µm voxel sizes, respectively, from pre- and post-implantation micro-Computed Tomography (µCT) images (vivaCT40, Scanco Medical, Switzerland). Bone volume (BV) around the screw and in front of the screw tip, and tip-to-joint distance (TJD) were evaluated on the µCT images. The µFE models and BV were used to predict the experimental force at the initial
Objective. From our series of 570 Dynesys flexible stabilisation procedures, we studied two prospective series of patients with a minimum one-year follow-up comparing uncoated and hydroxyapatite-coated (HA) screws. Methods. Patients were entered prospectively and followed up at 6 weeks, 3, 6, and 12 months and annually thereafter. Plain radiographs were obtained annually. 58 patients who underwent Dynesys stabilisation with HA coated screws (312 screws) were evaluated. The data was compared with 71 patients who underwent Dynesys stabilisation with non-coated pedicle screws (366 screws). Outcome measures were
Proximal humerus fractures (PHF) are the third most common fractures in the elderly. Treatment of complex PHF has remained challenging with mechanical failure rates ranging up to 35% even when state-of-the-art locked plates are used. Secondary (post-operative) screw perforation through the articular surface of the humeral head is the most frequent mechanical failure mode, with rates up to 23%. Besides other known risk factors, such as non-anatomical reduction and lack of medial cortical support, in-adverse intraoperative perforation of the articular surfaces during pilot hole drilling (overdrilling) may increase the risk of secondary screw perforation. Overdrilling often occurs during surgical treatment of osteoporotic PHF due to minimal tactile feedback; however, the awareness in the surgical community is low and the consequences on the fixation stability have remained unproved. Therefore, the aim of this study was to evaluate biomechanically whether overdrilling would increase the risk of cyclic screw perforation failure in unstable PHF. A highly unstable malreduced 3-part fracture was simulated by osteotomizing 9 pairs of fresh-frozen human cadaveric proximal humeri from elderly donors (73.7 ± 13.0 ys, f/m: 3/6). The fragments were fixed with a locking plate (PHILOS, DePuy Synthes, Switzerland) using six proximal screws, with their lengths selected to ensure 6 mm tip-to-joint distance. The pairs were randomized into two treatment groups, one with all pilot holes accurately predrilled (APD) and another one with the boreholes of the two calcar screws overdrilled (COD). The constructs were tested under progressively increasing cyclic loading to failure at 4 Hz using a previously developed setup and protocol. Starting from 50 N, the peak load was increased by 0.05 N/cycle. The event of initial
Aims. The modified Dunn procedure has the potential to restore the anatomy in hips with severe slipped capital femoral epiphyses (SCFE). However, there is a risk of developing avascular necrosis of the femoral head (AVN). In this paper, we report on clinical outcome, radiological outcome, AVN rate and complications, and the cumulative survivorship at long-term follow-up in patients undergoing the modified Dunn procedure for severe SCFE. Patients and Methods. We performed a retrospective analysis involving 46 hips in 46 patients treated with a modified Dunn procedure for severe SCFE (slip angle > 60°) between 1999 and 2016. At nine-year-follow-up, 40 hips were available for clinical and radiological examination. Mean preoperative age was 13 years, and 14 hips (30%) presented with unstable slips. Mean preoperative slip angle was 64°. Kaplan–Meier survivorship was calculated. Results. At the latest follow-up, the mean Merle d’Aubigné and Postel score was 17 points (14 to 18), mean modified Harris Hip Score was 94 points (66 to 100), and mean Hip Disability and Osteoarthritis Outcome Score was 91 points (67 to 100). Postoperative slip angle was 7° (1° to 16°). One hip (2%) had progression of osteoarthritis (OA). Two hips (5%) developed AVN of the femoral head and required further surgery. Three other hips (7%) underwent implant revision due to
We have studied two matching cohorts of patients treated by Dynesys flexible stabilisation with and without hydroxyapatite (HA) coating of the pedicle screws. From our series of 570 Dynesys procedures, we studied patients with HA coated screws with a minimum one year follow-up. Patients were entered prospectively and followed up at 6 weeks, 3, 6, and 12 months and annually thereafter. Plain radiographs were obtained annually. 58 patients (26 males, 32 females, mean age 55 years at surgery) underwent Dynesys stabilisation with HA coated screws. The data was compared with 69 patients who underwent Dynesys stabilisation with non-coated pedicle screws between 2004 and 2006 (26 male, 53 female, mean age 54 years). Outcome measures were
Purpose of Study. To review the medium-term results of the Dynesys stabilisation system used in 113 consecutive patients with discogenic back pain. Methods and Results. 113 consecutive patients with discogenic back pain were treated with Dynesys as the sole intervention. Inclusion criteria included mri proven disc degeneration and an improvement in symptoms following an injection into the disc with local anaesthetic and steroid (spinal disc probing). Patients were followed up for a minimum of 5 years, with outcome measures including SF-36, Oswestry disability index (ODI) and visual pain analogue scores (VPAS). Additional factors reviewed included previous spinal operations, complications, loosening and revision rates with subsequent outcomes. Mean pre-operative ODI was 49.5, SF-36 was 37.6 and VPAS back pain was 60.9. At one year post operatively, these scores were 36.9, 49.4 and 39.8, at five years follow up, the scores were 33.3, 51.8 and 40.1 respectively. We note wide variations in our results. Several significant factors appear to contribute to the outcome of surgery. These include undergoing surgery before the age of 43, no more than 2-level disc degeneration, leg pain less than VPAS 4, and no previous spinal surgery. 19 patients had
Surgical treatment of fragility sacrum fractures with percutaneous sacroiliac (SI) screw fixation is associated with high failure rates in terms of
Purpose: Intra-articular screw penetration with the use of proximal humeral locking plates has a reported incidence in the literature of up 25%. It may occur early, due to an intra-operative unrecognized technical error, or as a result of late fracture collapse. This study was designed to demonstrate the “approach-withdraw” technique of intra-operative fluoroscopy which can be used to minimize the rate of early unrecognized intra-articular screw penetration. Method: A radiographic review was undertaken of 37 patients with proximal humerus fractures fixed with either the PHILOS plate (Synthes, Westchester, Pennsylvania) or the Periloc proximal humerus plate (Smith and Nephew, Memphis, TN) by the senior author (JY) between 2002 and 2009. Intra-operative fluoroscopy was used in each case to ensure there was no intra-articular screw encroachment by visualizing each screw tip approach and then withdraw from the articular surface during live fluoroscopy as the shoulder was taken through a range of motion. Patients were then followed for an average of nine months with serial radiographs for post-operative intra-articular screw penetration,
Introduction. Hips following in-situ pinning for slipped capital femoral epiphysis (SCFE) have an altered morphology of the proximal femur with cam type deformity. This deformity can result in femoroacetabular impingement and early joint degeneration. The modified Dunn procedure allows to reorientate the slipped epiphysis to restore hip morphology and function. Objectives. To evaluate (1) hip pain and function, (2) 10-year survival rate and (3) subsequent surgeries and complications in hips undergoing modified Dunn procedure for SCFE. Methods. Between April 1998 and December 2005 we performed the modified Dunn procedure for 43 patients (43 hips) with SCFE. Twenty-five hips (58) presented with an acute or acute on chronic slip. The mean slip angle was 43° (range, 15° – 80°). A majority of 53% of procedures were performed in male patients and the mean age at operation was 13 years (10 – 19 years). We could followup all except one hip (followup of 5.5 year) for a minimum of 10 years (mean followup 13 [10 – 18 years]). We used the anterior impingement test to assess pain and the Merle d'Aubigné- ostel score to assess function. Survivorship calculation was performed using the method of Kaplan and Meier and any of the following factors as a definition of failure: radiographic evidence of worsening osteoarthritis (OA), or a Merle d'Aubigné-Postel score less than 15. Results. (1) The prevalence of a positive anterior impingement test decreased from 100% to 16% (p<0.001). The mean Merle d'Aubigné-Postel score improved from 13 (7 – 14) to 17 (14 – 18) at most recent followup (p<0.001). (2) Four hips (9%) showed progression of OA and three hips (7%) had a Merle d'Aubigné-Postel score of less than 15 at most recent followup. This resulted in a 93% survival rate at 10-year followup. (3) No hip developed avascular necrosis. Five hips (12%) had complications with reosteosynthesis due to
The validation of a new classification of the external fixator screw-bone interface.
During the last decade or more, the anchors used for instrumentation in scoliosis surgery are predominantly transpedicular screws, according to Suk. The long term radiographical feature of screw fixation after scoliosis surgery is not previously studied. A consecutive series of 81 cases with AIS operated on with an all screw construct has been studied by means of low dose CT postoperatively and at 2 years postoperatively. There were 67 females and 14 males, with a mean age of 18.3 ± 3 years. In 26 / 81 (32 %) there were signs of loosing of one or more screws, at a maximum 3 screws. We observed loosened screws in the upper thoracic region in 16 cases, in the thoracolumbar 6 and in lumbar area in 4. Mean pre-op Cobb angle was 56 in cases of loosening and 53 of intact screw fixation (n.s.), the correction rate was 69% in loosened vs 70% among intact screws (n.s.). In males there were signs of loosening in 8/14 (57%) and in females 18/67 (27%). Among cases with loosening, 14% had suboptimal screw positioning postoperatively, in intact cases it was observed in 11% (n.s.). In the whole group there were signs of suboptimal screw positioning 12%. Clinically, 1 case had a loosened L4 screw replaced; and at all 21/26 had no complaints and 5/26 reported minor pain or discomfort. 1/26 had a minor proximal junctional kyphosis about 10°, in 3/26 there was a pull-out of some few mms. With plain radiography loosening could be observed in 11/26 cases; 5 were in the lumbar region. In a consecutive series of 81 adolescents with idiopathic scoliosis who had underwent scoliosis surgery according to Suk, one third showed, 2 years after the intervention, some minor
Introduction. To compare the union rates and post-operative mobility of antegrade intramedullary nailing of osteoporotic traumatic supracondylar femoral fractures (AO classification A to C2) with those of plating. Materials/Methods. We studied any traumatic intra or extra-articular supracondylar femoral fracture from 2005–2010. Patients were either admitted directly to our level 1 trauma centre or were referred from another hospital. Nineteen patients were identified, consisting of primarily fixation with five antegrade nails and fourteen plates. We defined osteoporotic bone as being present in anyone over sixty years old or who had a clinical diagnosis. One nail and six plates were excluded due to young age or fracture severity. This left four nails, six less invasive stabilisation system plates and two dynamic condylar screw plates. Both groups were comparable with respect to age, sex and AO fracture classification. Results. There was a significant difference in achieving union between the two groups (p=0.040). Union occurred within three months in all four fractures in the nail group but only three fractures (38%) united after primary fixation in the plate group. There were two failures due to screw pullout, one failure due to
The aim of this study was to assess the clinical and radiological results of patients who were revised using a custom-made triflange acetabular component (CTAC) for component loosening and pelvic discontinuity (PD) after previous total hip arthroplasty (THA). Data were extracted from a single centre prospective database of patients with PD who were treated with a CTAC. Patients were included if they had a follow-up of two years. The Hip Disability and Osteoarthritis Outcome Score (HOOS), modified Oxford Hip Score (mOHS), EurQol EuroQoL five-dimension three-level (EQ-5D-3L) utility, and Numeric Rating Scale (NRS), including visual analogue score (VAS) for pain, were gathered at baseline, and at one- and two-year follow-up. Reasons for revision, and radiological and clinical complications were registered. Trends over time are described and tested for significance and clinical relevance.Aims
Methods
Traditional procedures for orthopedic total joint replacements have relied upon bone cement to achieve long-term implant fixation. This remains the gold standard in number of procedures including TKR and PKR. In many cases however, implants fixed with cement have proven susceptible to aseptic loosening and 3. rd. body wear concerns. These issues have led to a shift away from cement fixation and towards devices that rely on the natural osteoconductive properties of bone and the ability of porous-coated implants to initiate on-growth and in-growth at the bone interface, leading to more reliable fixation. To facilitate long-term fixation through osseointegration, several mechanical means have been utilized as supplemental mechanism to aid in stabilizing the prostheses. These methods have included integrated keels and bone screws. The intent of these components is to limit implant movement and provide a stable environment for bone ingrowth to occur. Both methods have demonstrated limitations on safety and performance including bone fracture due keel induced stresses, loosening due to inconsistent pressfit of the keel, screw-thread stripping in cancellous bone, head-stripping, screw fracture,
Introduction: In this study, we report interobserver reliability of X-ray for the interpretation of pedicle screw osteointegration based on the diagnosis of “Halo zone” surrounding the screw. Dynamic stabilisation system for the spine relies on titanium screw purchase within the pedicle. Decision on osteointegration is important especially when the patient becomes symptomatic following initial good outcome. From our cohort of 420 Dynesys patients, over all incidence of
Introduction: In this study, we report interobserver reliability of X-ray for the interpretation of pedicle screw osteointegration based on the diagnosis of “Halo zone” surrounding the screw. Dynamic stabilisation system for the spine relies on titanium screw purchase within the pedicle. Decision on osteointegration is important especially when the patient becomes symptomatic following initial good outcome. From our cohort of 420 Dynesys patients, over all incidence of
