The AO Foundation advocates the use of partially
threaded lag screws in the fixation of fractures of the medial malleolus.
However, their threads often bypass the radiodense physeal scar
of the distal tibia, possibly failing to obtain more secure purchase
and better compression of the fracture. We therefore hypothesised that the partially threaded screws
commonly used to fix a medial malleolar fracture often provide suboptimal
compression as a result of bypassing the physeal scar, and proposed
that better compression of the fracture may be achieved with shorter
partially threaded screws or fully threaded screws whose threads
engage the physeal scar. We analysed compression at the fracture site in human cadaver
medial malleoli treated with either 30 mm or 45 mm long partially
threaded screws or 45 mm fully threaded screws. The median compression
at the fracture site achieved with 30 mm partially threaded screws
(0.95 kg/cm2 (interquartile range (IQR) 0.8 to 1.2) and
45 mm fully threaded screws
(1.0 kg/cm2 (IQR 0.7 to 2.8)) was significantly higher
than that achieved with 45 mm partially threaded screws (0.6 kg/cm2 (IQR
0.2 to 0.9)) (p = 0.04 and p <
0.001, respectively). The fully
threaded screws and the 30mm partially threaded screws were seen
to engage the physeal scar under an image intensifier in each case. The results support the use of 30 mm partially threaded or 45
mm fully threaded screws that engage the physeal scar rather than
longer partially threaded screws that do not. A
45 mm fully threaded screw may in practice offer additional benefit
over 30 mm partially threaded screws in increasing the thread count
in the denser paraphyseal region. Cite this article:
We reviewed the records of 431 patients who had open reduction and internal fixation of the scaphoid performed by one surgeon (TJH) over a 13-year period. The Herbert bone screw provided adequate internal fixation without the use of plaster immobilisation, promoting a rapid functional recovery. On average, patients returned to work 4.7 weeks after surgery and wrist function was significantly improved, even when the fracture failed to unite. Healing rates for acute fractures were better than those reported for plaster immobilisation and were independent of fracture location. In the case of established nonunions, healing depended on the stage and location of the fracture, but the progress of arthritis was halted and carpal collapse significantly improved. Internal fixation of the scaphoid using the Herbert bone screw, although technically demanding, has few complications and appears to offer significant advantages over other methods of treatment.
We describe a method of internal fixation for femoral neck fractures which has been newly developed to reduce the frequency of early complications. Two cannulated screws are inserted in the axis of the femoral neck to reach into the subchondral bone of the femoral head. The screws are inserted over guide pins and the tip of the screw is self-tapping and designed to provide good anchorage in the femoral head. We used this method in 44 consecutive patients in a prospective study with no exclusions, followed for a minimum of 24 months. All fractures healed within 12 months, and there were no cases of early loosening or nonunion. In four cases, late segmental collapse had developed during the mean follow-up period of 30 months.
The spinal manifestations of neurofibromatosis include cervicothoracic kyphosis, in which scalloping of the vertebral body and erosion of the pedicles may render conventional techniques of fixation impossible. We describe a case of cervicothoracic kyphosis managed operatively with a vascularised fibular graft anteriorly across the apex of the kyphus, followed by a long posterior construct using translaminar screws, which allow segmental fixation in vertebral bodies where placement of the pedicle screws was impracticable.
Ununited fractures of the scaphoid with extensive bone resorption are usually treated by bone grafting and internal fixation, using either an open or a minimally invasive technique. We studied the feasibility of percutaneous fixation without bone grafting in a consecutive series of 27 patients with established nonunion of an undisplaced fracture of the scaphoid and extensive local resorption of bone. They were treated by a single surgeon with rigid fixation alone, using a headless cannulated screw inserted through a volar percutaneous technique. Clinical examination, standard radiographs and CT confirmed that the fracture had united in all patients at a mean of 11.6 weeks (8 to 16), and that their functional scores had improved. We concluded that extensive resorption at the fracture site is not an absolute indication for bone grafting, and that percutaneous fixation alone will eventually produce healing of ununited undisplaced fractures of the scaphoid regardless of the size of the gap.
To devise a method to quantify and optimize tightness when inserting cortical screws, based on bone characterization and screw geometry. Cortical human cadaveric diaphyseal tibiae screw holes (n = 20) underwent destructive testing to firstly establish the relationship between cortical thickness and experimental stripping torque (Tstr), and secondly to calibrate an equation to predict Tstr. Using the equation’s predictions, 3.5 mm screws were inserted (n = 66) to targeted torques representing 40% to 100% of Tstr, with recording of compression generated during tightening. Once the target torque had been achieved, immediate pullout testing was performed.Aims
Methods
In patients with osteoporosis there is always
a strong possibility that pedicle screws will loosen. This makes
it difficult to select the appropriate osteoporotic patient for
a spinal fusion. The purpose of this study was to determine the
correlation between bone mineral density (BMD) and the magnitude
of torque required to insert a pedicle screw. To accomplish this,
181 patients with degenerative disease of the lumbar spine were
studied prospectively. Each underwent dual-energy x-ray absorptiometry
(DEXA) and intra-operative measurement of the torque required to
insert each pedicle screw. The levels of torque generated in patients
with osteoporosis and osteopenia were significantly lower than those
achieved in normal patients. Positive correlations were observed between
BMD and T-value at the instrumented lumbar vertebrae, mean BMD and
mean T-value of the lumbar vertebrae, and mean BMD and mean T-value
of the proximal femur. The predictive torque (Nm) generated during pedicle
screw insertion was [-0.127 + 1.62 × (BMD at the corresponding lumbar
vertebrae)], as measured by linear regression analysis. The positive
correlation between BMD and the maximum torque required to insert
a pedicle screw suggests that pre-operative assessment of BMD may
be useful in determining the ultimate strength of fixation of a
device, as well as the number of levels that need to be fixed with
pedicle screws in patients who are suspected of having osteoporosis.
Deficiency of the anterior cruciate ligament (ACL) is a common disorder which can lead to changes in lifestyle. We followed 59 patients who had had arthroscopic reconstruction of the ACL using a central-third patellar-tendon autograft for seven years to assess the long-term effectiveness of recent advances in reconstruction of the ACL. The standard criteria for evaluation of the International Knee Documentation Committee, the Lysholm knee score and measurements using the KT 1000 arthrometer all showed satisfactory results. Deterioration in the clinical performance after seven years was associated with osteoarthritic changes and correlated with chronic ligament injuries and meniscectomy. There were three traumatic and three spontaneous ruptures. We believe that the procedure can be successful, but remain concerned about failure of the graft and osteoarthritis. The results raise questions about the best time to operate and suggest that early surgery may reduce the risk of osteoarthritis.
We created virtual three-dimensional reconstruction models from computed tomography scans obtained from patients with acetabular fractures. Virtual cylindrical implants were placed intraosseously in the anterior column, the posterior column and across the dome of the acetabulum. The maximum diameter which was entirely contained within the bone was determined for each position of the screw. In the same model, the cross-sectional diameters of the columns were measured and compared to the maximum diameter of the corresponding virtual implant. We found that the mean maximum diameter of virtual implant accommodated by the anterior columns was 6.4 mm and that the smallest diameter of the columns was larger than the maximum diameter of the equivalent virtual implant. This study suggests that the size of the screw used for percutaneous fixation of acetabular fractures should not be based solely on the measurement of cross-sectional diameter and that virtual three-dimensional reconstructions might be useful in pre-operative planning.
We report a prospective study of 198 cases of subcapital fracture of the femur treated by closed reduction and fixation with a sliding compression screw-plate. This was done without regard to the patient's age or the Garden stage of the fracture. Early weight-bearing was encouraged. Of the displaced fractures 23% failed in the first year because of non-union or infection. Of the fractures which united 27% had developed avascular necrosis after three years. Despite this we believe that the sliding compression screw-plate, of proven value in the treatment of intertrochanteric fractures, is also useful for the fixation of subcapital fractures.
Various techniques have been used for the fixation of the posterior pelvis, each with disadvantages specific to the technique. In this study, a new protocol involving the placement of posterior pelvic screws in the CT suite is described and evaluated. A total of 66 patients with unstable pelvic ring injuries was stabilised under local anaesthesia with sedation. The mean length of time for the procedure was 26 minutes per screw. There were no technical difficulties or misplaced screws and no cases of infection or nonunion. All patients stated that they would choose to have the CT scan procedure again rather than a procedure requiring general anaesthesia. The charges for the procedure were approximately £1840 ($2800) per operation. CT-guided placement of iliosacral screws is a safe, feasible, and cost-effective alternative to radiologically-guided placement in the operating theatre in selected patients.
One hundred and twenty-seven consecutive patients with displaced subcapital fractures of the femoral neck (Garden Grade III or IV) all under 80 years of age and independently mobile, were randomly allocated to fixation with either double divergent pins or a single sliding screw-plate device. The incidence of non-union and infection in the sliding screw-plate group was significantly higher, and we believe that when internal fixation is considered appropriate multiple pinning should be used. Mobility after treatment was disappointing in about half of the patients, and we feel that internal fixation can only be justified in patients who are physiologically well preserved and who maintain a high level of activity.
The aim of this study was to systematically compare the safety and accuracy of robot-assisted (RA) technique with conventional freehand with/without fluoroscopy-assisted (CT) pedicle screw insertion for spine disease. A systematic search was performed on PubMed, EMBASE, the Cochrane Library, MEDLINE, China National Knowledge Infrastructure (CNKI), and WANFANG for randomized controlled trials (RCTs) that investigated the safety and accuracy of RA compared with conventional freehand with/without fluoroscopy-assisted pedicle screw insertion for spine disease from 2012 to 2019. This meta-analysis used Mantel-Haenszel or inverse variance method with mixed-effects model for heterogeneity, calculating the odds ratio (OR), mean difference (MD), standardized mean difference (SMD), and 95% confidence intervals (CIs). The results of heterogeneity, subgroup analysis, and risk of bias were analyzed.Aims
Methods
Aims. This study aimed to establish the optimal fixation methods for calcaneal tuberosity avulsion fractures with different fragment thicknesses in a porcine model. Methods. A total of 36 porcine calcanea were sawed to create simple avulsion fractures with three different fragment thicknesses (5, 10, and 15 mm). They were randomly fixed with either two suture anchors or one headless screw. Load-to-failure and cyclic loading tension tests were performed for the biomechanical analysis. Results. This biomechanical study predicts that headless
Bone defects are frequently observed in anterior shoulder instability. Over the last decade, knowledge of the association of bone loss with increased failure rates of soft-tissue repair has shifted the surgical management of chronic shoulder instability. On the glenoid side, there is no controversy about the critical glenoid bone loss being 20%. However, poor outcomes have been described even with a subcritical glenoid bone defect as low as 13.5%. On the humeral side, the Hill-Sachs lesion should be evaluated concomitantly with the glenoid defect as the two sides of the same bipolar lesion which interact in the instability process, as described by the glenoid track concept. We advocate adding remplissage to every Bankart repair in patients with a Hill-Sachs lesion, regardless of the glenoid bone loss. When critical or subcritical glenoid bone loss occurs in active patients (> 15%) or bipolar off-track lesions, we should consider anterior glenoid bone reconstructions. The techniques have evolved significantly over the last two decades, moving from open procedures to arthroscopic, and from
The February 2023 Wrist & Hand Roundup. 360. looks at: ‘Self-care’ protocol for minimally displaced distal radius fractures; Treatment strategies for acute Seymour fractures in children and adolescents: including crushed open fractures; Routinely collected outcomes of proximal row carpectomy; Moving minor hand surgeries in the office-based procedure room: a population-based trend analysis; A comparison between robotic-assisted scaphoid
Aims. The primary aim of this study was to present the mid-term follow-up of a multicentre randomized controlled trial (RCT) which compared the functional outcome following routine removal (RR) to the outcome following on-demand removal (ODR) of the syndesmotic screw (SS). Methods. All patients included in the ‘ROutine vs on DEmand removal Of the syndesmotic screw’ (RODEO) trial received the Olerud-Molander Ankle Score (OMAS), American Orthopaedic Foot and Ankle Hindfoot Score (AOFAS), Foot and Ankle Outcome Score (FAOS), and EuroQol five-dimension questionnaire (EQ-5D). Out of the 152 patients, 109 (71.7%) completed the mid-term follow-up questionnaire and were included in this study (53 treated with RR and 56 with ODR). Median follow-up was 50 months (interquartile range 43.0 to 56.0) since the initial surgical treatment of the acute syndesmotic injury. The primary outcome of this study consisted of the OMAS scores of the two groups. Results. The median OMAS score was 85.0 for patients treated with RR, and 90.0 for patients treated with ODR (p = 0.384), indicating no significant difference between ODR and RR. The secondary outcome measures included the AOFAS (88.0 in the RR group and 90.0 for ODR; p = 0.722), FAOS (87.5 in the RR group and 92.9 for ODR; p = 0.399), and EQ-5D (0.87 in the RR group and 0.96 for ODR; p = 0.092). Conclusion. This study demonstrated no functional difference comparing ODR to RR in syndesmotic injuries at a four year follow-up period, which supports the results of the primary RODEO trial. ODR should be the standard practice after syndesmotic
Aims. The aim of this study was to examine the implant accuracy of custom-made partial pelvis replacements (PPRs) in revision total hip arthroplasty (rTHA). Custom-made implants offer an option to achieve a reconstruction in cases with severe acetabular bone loss. By analyzing implant deviation in CT and radiograph imaging and correlating early clinical complications, we aimed to optimize the usage of custom-made implants. Methods. A consecutive series of 45 (2014 to 2019) PPRs for Paprosky III defects at rTHA were analyzed comparing the preoperative planning CT scans used to manufacture the implants with postoperative CT scans and radiographs. The anteversion (AV), inclination (IC), deviation from the preoperatively planned implant position, and deviation of the centre of rotation (COR) were explored. Early postoperative complications were recorded, and factors for malpositioning were sought. The mean follow-up was 30 months (SD 19; 6 to 74), with four patients lost to follow-up. Results. Mean CT defined discrepancy (Δ) between planned and achieved AV and IC was 4.5° (SD 3°; 0° to 12°) and 4° (SD 3.5°; 1° to 12°), respectively. Malpositioning (Δ > 10°) occurred in five hips (10.6%). Native COR reconstruction was planned in 42 cases (93%), and the mean 3D deviation vector was 15.5 mm (SD 8.5; 4 to 35). There was no significant influence in malpositioning found for femoral stem retention, surgical approach, or fixation method. Conclusion. At short-term follow-up, we found that PPR offers a viable solution for rTHA in cases with massive acetabular bone loss, as highly accurate positioning can be accomplished with meticulous planning, achieving anatomical reconstruction. Accuracy of achieved placement contributed to reduced complications with no injury to vital structures by