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Bone & Joint Open
Vol. 5, Issue 8 | Pages 652 - 661
8 Aug 2024
Taha R Davis T Montgomery A Karantana A

Aims

The aims of this study were to describe the epidemiology of metacarpal shaft fractures (MSFs), assess variation in treatment and complications following standard care, document hospital resource use, and explore factors associated with treatment modality.

Methods

A multicentre, cross-sectional retrospective study of MSFs at six centres in the UK. We collected and analyzed healthcare records, operative notes, and radiographs of adults presenting within ten days of a MSF affecting the second to fifth metacarpal between 1 August 2016 and 31 July 2017. Total emergency department (ED) attendances were used to estimate prevalence.


Bone & Joint Open
Vol. 5, Issue 2 | Pages 123 - 131
12 Feb 2024
Chen B Duckworth AD Farrow L Xu YJ Clement ND

Aims

This study aimed to determine whether lateral femoral wall thickness (LWT) < 20.5 mm was associated with increased revision risk of intertrochanteric fracture (ITF) of the hip following sliding hip screw (SHS) fixation when the medial calcar was intact. Additionally, the study assessed the association between LWT and patient mortality.

Methods

This retrospective study included ITF patients aged 50 years and over treated with SHS fixation between 2019 and 2021 at a major trauma centre. Demographic information, fracture type, delirium status, American Society of Anesthesiologists grade, and length of stay were collected. LWT and tip apex distance were measured. Revision surgery and mortality were recorded at a mean follow-up of 19.5 months (1.6 to 48). Cox regression was performed to evaluate independent risk factors associated with revision surgery and mortality.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_9 | Pages 92 - 92
17 Apr 2023
Raina D Mrkonjic F Tägil M Lidgren L
Full Access

A number of techniques have been developed to improve the immediate mechanical anchorage of implants for enhancing implant longevity. This issue becomes even more relevant in patients with osteoporosis who have fragile bone. We have previously shown that a dynamic hip screw (DHS) can be augmented with a calcium sulphate/hydroxyapatite (CaS/HA) based injectable biomaterial to increase the immediate mechanical anchorage of the DHS system to saw bones with a 400% increase in peak extraction force compared to un-augmented DHS. The results were also at par with bone cement (PMMA). The aim of this study was to investigate the effect of CaS/HA augmentation on the integration of a different fracture fixation device (gamma nail lag-screw) with osteoporotic saw bones. Osteoporotic saw bones (bone volume fraction = 15%) were instrumented with a gamma nail without augmentation (n=8) or augmented (n=8) with a CaS/HA biomaterial (Cerament BVF, Bonesupport AB, Sweden) using a newly developed augmentation method described earlier. The lag-screws from both groups were then pulled out at a displacement rate of 0.5 mm/s until failure. Peak extraction force was recorded for each specimen along with photographs of the screws post-extraction. A non-parametric t-test was used to compare the two groups. CaS/HA augmentation of the lag-screw led to a 650% increase in the peak extraction force compared with the controls (p<0.01). Photographs of the augmented samples shows failure of the saw-bones further away from the implant-bone interface indicating a protective effect of the CaS/HA material. We present a novel method to enhance the immediate mechanical anchorage of a lag-screw to osteoporotic bone and it is also envisaged that CaS/HA augmentation combined with systemic bisphosphonate treatment can lead to new bone formation and aid in the reduction of implant failures and re-operations


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 55 - 55
11 Apr 2023
Raina D Markeviciute V Arvidsson L Törnquist E Stravinskas M Kok J Jacobson I Liu Y Tengattini A Sezgin E Vater C Zwingenberger S Isaksson H Tägil M Tarasevicius S Lidgren L
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Majority of osteoporosis related fractures are treated surgically using metallic fixation devices. Anchorage of fixation devices is sometimes challenging due to poor osteoporotic bone quality that can lead to failure of the fracture fixation. Using a rat osteoporosis model, we employed neutron tomography and histology to study the biological effects of implant augmentation using an isothermally setting calcium sulphate/hydroxyapatite (CaS/HA) biomaterial with synthetic HA particles as recruiting moiety for systemically administered bisphosphonates. Using an osteoporotic sawbones model, we then provide a standardized method for the delivery of the CaS/HA biomaterial at the bone-implant interface for improved mechanical anchorage of a lag-screw commonly used for hip fracture fixation. As a proof-of-concept, the method was then verified in donated femoral heads and in patients with osteoporosis undergoing hip fracture fixation. We show that placing HA particles around a stainless-steel screw in-vivo, systemically administered bisphosphonates could be targeted towards the implant, yielding significantly higher peri-implant bone formation compared to un-augmented controls. In the sawbones model, CaS/HA based lag-screw augmentation led to significant increase (up to 4 times) in peak extraction force with CaS/HA performing at par with PMMA. Micro-CT imaging of the CaS/HA augmented lag-screws in cadaver femoral heads verified that the entire length of the lag-screw threads and the surrounding bone was covered with the CaS/HA material. X-ray images from fracture fixation surgery indicated that the CaS/HA material could be applied at the lag-screw-bone interface without exerting any additional pressure or risk of venous vascular leakage.: We present a new method for augmentation of lag-screws in fragile bone. It is envisaged that this methodcould potentially reduce the risk of fracture fixation failure especially when HA seeking “bone active” drugs are used systemically


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_2 | Pages 113 - 113
10 Feb 2023
Burrows K Lock A Smith Z McChesney S
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Failure of cephalomedullary fixation for proximal femur fractures is an uncommon event associated with significant morbidity to the patient and cost to the healthcare system. This institution changed nailing system from the PFNA (DePuy Synthes) to InterTan (Smith and Nephew) in February 2020. To assess for non-inferiority, a retrospective review was performed on 247 patients treated for unstable proximal femur fractures (AO 31 A2; A3). Patients were identified through manual review of fluoroscopic images. Stable fracture patterns were excluded (AO 31 A1). Pre/post operative imaging, demographic data, operative time and ASA scores assessed. Internal/external imaging and national joint registry data were reviewed for follow up. No significant difference was found in overall failure rate of PFNA vs InterTan (4.84% vs 3.23%; p = 0.748). Overall, short nails were more likely to fail by cut-out than long nails (7.5% vs 1.2%; p = 0.015). Nails which failed by varus cut-out had a higher tip/apex distance (TAD) (26.2mm vs 17.0mm; p < 0.001). Of concern, varus cut-out occurred in two InterTan nails with TAD of <25mm. The PFNA enjoyed a shorter operative time for both the short (59.1 vs 71.8 mins; p = 0.022) and long nails (98.8 vs 114.3 mins; p = 0.016) with no difference in 120-day survival rate. Overall failure rates of the PFNA and InterTan nailing systems were comparable. However, the failure rate of short nails in this study is concerning. Using long nails with a lag screw design for unstable intertrochanteric femoral fractures may reduce failure rates. Cumulative frequency analysis suggests stringent tip-apex distances of less than 21mm may reduce failure rates in lag-screw design cephulomedullary nails. This dataset suggests that unstable intertrochanteric fractures may be more reliably managed with a long cephalomedullary device


The Bone & Joint Journal
Vol. 100-B, Issue 1 | Pages 95 - 100
1 Jan 2018
Evers J Fischer M Zderic I Wähnert D Richards RG Gueorguiev B Raschke MJ Ochman S

Aims

The aim of this study was to investigate the effect of a posterior malleolar fragment (PMF), with < 25% ankle joint surface, on pressure distribution and joint-stability. There is still little scientific evidence available to advise on the size of PMF, which is essential to provide treatment. To date, studies show inconsistent results and recommendations for surgical treatment date from 1940.

Materials and Methods

A total of 12 cadaveric ankles were assigned to two study groups. A trimalleolar fracture was created, followed by open reduction and internal fixation. PMF was fixed in Group I, but not in Group II. Intra-articular pressure was measured and cyclic loading was performed.


Bone & Joint Research
Vol. 6, Issue 8 | Pages 481 - 488
1 Aug 2017
Caruso G Bonomo M Valpiani G Salvatori G Gildone A Lorusso V Massari L

Objectives. Intramedullary fixation is considered the most stable treatment for pertrochanteric fractures of the proximal femur and cut-out is one of the most frequent mechanical complications. In order to determine the role of clinical variables and radiological parameters in predicting the risk of this complication, we analysed the data pertaining to a group of patients recruited over the course of six years. Methods. A total of 571 patients were included in this study, which analysed the incidence of cut-out in relation to several clinical variables: age; gender; the AO Foundation and Orthopaedic Trauma Association classification system (AO/OTA); type of nail; cervical-diaphyseal angle; surgical wait times; anti-osteoporotic medication; complete post-operative weight bearing; and radiological parameters (namely the lag-screw position with respect to the femoral head, the Cleveland system, the tip-apex distance (TAD), and the calcar-referenced tip-apex distance (CalTAD)). Results. The incidence of cut-out across the sample was 5.6%, with a higher incidence in female patients. A significantly higher risk of this complication was correlated with lag-screw tip positioning in the upper part of the femoral head in the anteroposterior radiological view, posterior in the latero-lateral radiological view, and in the Cleveland peripheral zones. The tip-apex distance and the calcar-referenced tip-apex distance were found to be highly significant predictors of the risk of cut-out at cut-offs of 30.7 mm and 37.3 mm, respectively, but the former appeared more reliable than the latter in predicting the occurrence of this complication. Conclusion. The tip-apex distance remains the most accurate predictor of cut-out, which is significantly greater above a cut-off of 30.7 mm. Cite this article: G. Caruso, M. Bonomo, G. Valpiani, G. Salvatori, A. Gildone, V. Lorusso, L. Massari. A six-year retrospective analysis of cut-out risk predictors in cephalomedullary nailing for pertrochanteric fractures: Can the tip-apex distance (TAD) still be considered the best parameter?. Bone Joint Res 2017;6:481–488. DOI: 10.1302/2046-3758.68.BJR-2016-0299.R1


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_2 | Pages 5 - 5
1 Jan 2014
Parker L Ray P Grechenig S Grechenig W
Full Access

When inserting a lag-screw across an arthrodesis, stress is concentrated under the screw head risking asymmetrical force distribution and fracture of the cortical bone bridge. The IO FiX (Extremity Medical, NJ USA) is a new intraosseous device comprising an X-Post on one side of and parallel to the arthrodesis and a lag-screw inserted through the head of the X-Post which reinforces the cortical bone bridge. The X-Post behaves as an internal washer improving force distribution across the arthrodesis. Being intraosseous, near to the neutral axis of bend also means the device is fatigue-resistant and soft tissue irritation is reduced. The IO FiX has not been independently verified and therefore we analysed its performance in a human cadaveric ankle model. Our null hypothesis was there is no difference in force generation and contact area in an ankle arthrodesis when the IO FiX is compared with partially-threaded lag-screws. We used ten randomized cadaver ankles with a mean age of seventy-one years (44–84 years) prepared with flat arthrodesis cuts. A Tek-scan (Boston, USA) pressure transducer was used to measure force and contact area produced when the IO FiX was compared with a standard lag-screw and washer. The median average force in the IO FiX group was 3.95 kg and 2.35 kg in the lag-screw group (p=<0.01 Wilcoxon signed-rank). The IO FiX was able to create a more uniform contact area within the arthrodesis with a median average of 3.41 cm. 2. compared with 2.42 cm. 2. in the lag-screw group (p=<0.03 Wilcoxon signed rank). Our results suggest the IO FiX improves force generation and contact area across the arthrodesis. With the theoretical advantages of reduced soft tissue irritation and a lower risk of fatigue failure, the IO FiX offers a significant advantage compared with traditional fixation techniques


The Bone & Joint Journal
Vol. 95-B, Issue 12 | Pages 1662 - 1666
1 Dec 2013
Parker L Garlick N McCarthy I Grechenig S Grechenig W Smitham P

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: Bone Joint J 2013;95-B:1662–6.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 450 - 450
1 Sep 2012
Kristensen H Brink O Thorninger R Borris L Andersen K
Full Access

Introduction. The purpose of the present study was to identify risk factors for lag-screw cut-out following osteosynthesis of intertrochanteric fractures. Materials and methods. The study was a case-control study using a sex and age matched control group. The fractures were classified according to Evans and OTA/AO classifications. Operative treatment was performed using dynamic hip-screw or cephalomedullary nailing systems. All patients were followed for at least 3–4 months postoperatively. The following risk factors were assessed: fracture type, quality of reduction by blinded assessment using a visual analogue scale, tip-apex distance (TAD) according to Baumgaertner, lag-screw positioning and other relevant additional risk factors in terms of walking ability, osteoporosis, cardio-vascular disease, neurological disease, diabetes, obesity, alcohol consumption and smoking. Results. 35 cases with lag-screw cut-out and 122 controls without cut-out, 124 women with a mean age of 84.9 (range: 51–95) years and 33 men with a mean age of 82.3 (range: 67–94) years were identified. Cut-out were significantly more frequent in OTA/AO type 31-A3 fractures (odds ratio (OR) 4.13; 95% CI: 1.50–11.36). The quality of reduction was significantly related to the risk of cut-out. The mean TAD was 26.5 mm in the case group and 21 mm in the control group. This difference was significant (chi square test p=0.046). Assessment of the lag-screw positioning showed that a central/central (OR 0.18; 95 % CI: 0.11–0.30) or central/inferior (OR 0.14; 95 % CI: 0.03–0.63) position was associated with a reduced risk for cut-out. None of the additional risk factors included in this study seemed to have any influence on the results. Conclusion. This study showed that fracture type, quality of reduction, TAD and lag-screw positioning were the most important risk factors for cut-out


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_II | Pages 276 - 276
1 May 2010
Chin K Gogi N Fulcher G Deshmukh S Shepherd D
Full Access

Introduction: Fracture of cortical long bone can be treated with open reduction and internal fixation. Although the lag-screw technique would provide a stronger compression across the fracture site, this may not translate directly into a significantly better mechanical stability of the construct. In narrow long bone such as the metacarpus, it may be technically difficult to over-drill the near cortex. In addition, the fracture configuration as well as the presence of soft tissue attachment and neurovascular bundle in such smaller bones may give rise to technical difficulty in fixation with all the screws from the same side. Hypothesis: We therefore propose to test the hypothesis that there is no difference in the mechanical stability of the construct, in terms of three points bending and axial loading, between fixation with lag screw (L) and cortical screw (1C) in long bone oblique fracture. Secondly, we proposed that fixation with alternate cortical screws from both sides of the cortices (2C) may confer a stronger mechanical stability than fixation with all screws from one side (1C). Method: A 12 cm long oblique osteotomy was created along the shaft of tibial saw bone to produce an artificial long oblique fracture. The two fragments were held together and precompressed similarly with reduction clamp. Lag screw technique (L), unilateral (1C) and bilateral (2C) simple cortical screws techniques were used to fix the fracture with a total of four 4.5mm cortical screw in each construct. The test piece was placed into position and compressed under displacement control using a Bose ElectroForce. ®. 3300 Series test instrument (Bose Corporation ElectroForce Systems Group, Minnesota USA). The displacement was applied at a rate of 0.42mm/s. The displacement and load were measured every 0.0586 seconds and recorded using Win-Test Software (Bose Corporation ElectroForce Systems Group, Minnesota USA). Result: In three-points bending, fixation with unilateral cortical screws (1C) provided the highest mean stiffness values of the three techniques with an average of 27.72 N/mm (standard deviation STD 4.90 N/mm). The lag screw technique (L) had slightly lower mean stiffness values with an average of 26.29 N/mm (STD 3.46 N/ mm). Fixation with opposing screws (2C) had a lowest mean stiffness averaging 18.31 N/mm (STD 14.49 N/ mm). In axial compression, unilateral cortical screws (1C) provided the highest average stiffness at 290.33 N/mm (STD 89.84 N/mm) The opposing pre-compression technique had an average stiffness of 241.24 N/ mm (STD 121.30 N/mm) and the lag screw technique 198.94 N/mm (STD 58.33N/mm). Conclusion: In conclusion, fixation with unilateral cortical screws (1C) provided a better mechanical stability than lag screw. Fixation with bilateral cortical screws (2C) did not provide a more stable construct than unilateral screw fixation


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 12 | Pages 1548 - 1557
1 Dec 2008
Brinkman J Lobenhoffer P Agneskirchner JD Staubli AE Wymenga AB van Heerwaarden RJ

New developments in osteotomy techniques and methods of fixation have caused a revival of interest of osteotomies around the knee. The current consensus on the indications, patient selection and the factors influencing the outcome after high tibial osteotomy is presented. This paper highlights recent research aimed at joint pressure redistribution, fixation stability and bone healing that has led to improved surgical techniques and a decrease of post-operative time to full weight-bearing.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 2 | Pages 145 - 154
1 Feb 2007
Giannoudis PV Tzioupis CC Pape H Roberts CS

With the development of systems of trauma care the management of pelvic disruption has evolved and has become increasingly refined. The goal is to achieve an anatomical reduction and stable fixation of the fracture. This requires adequate visualisation for reduction of the fracture and the placement of fixation. Despite the advances in surgical approach and technique, the functional outcomes do not always produce the desired result. New methods of percutaneous treatment in conjunction with innovative computer-based imaging have evolved in an attempt to overcome the existing difficulties. This paper presents an overview of the technical aspects of percutaneous surgery of the pelvis and acetabulum.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_II | Pages 247 - 247
1 May 2006
Robinson C Houshian S Khan L
Full Access

The purpose of this study was to prospectively audit the functional outcome and peri-operative complications associated with the use of a trochantericentry cephalomedullary nail to treat all low-energy subtrochanteric fractures. Methods: Over a 95 month period, we used the Long Gamma Nail (LGN) to treat a consecutive series of 302 locally-resident patients who sustained subtrochanteric fractures during low-energy trauma. We prospectively assessed the mortality, prevalence of complications and functional outcome during the first year post-injury. We used survivorship methodology to assess the rate of re-operations and implant revision during the first year after surgery. Results: By one year, 74 patients had died, 10 were untraceable and 7 refused to participate in follow-up. The remaining 211 patients had evaluation of their functional outcome and post-operative complications during the first year post-injury. The prognosis following an operatively-treated subtrochanteric fracture was similar to other proximal femoral fractures, with a one-year mortality of 24.5%, and an increased level of social dependence, increased use of walking aids and reduction in mobility amongst survivors. Re-operation was required in 27 patients (8.9%), although only 18 patients required nail revision. On survivorship analysis, 96.8% of fractures had healed by six months post-injury, and only five patients had confirmed non-unions, which were successfully treated with autogenous bone grafting. Lag-screw mechanical failure and fractures distal to the nail were seen in twelve (4%) and five (1.7%) patients respectively; all of these fractures subsequently healed after further treatment. Deep sepsis occurred in only five (1.7%) patients. Conclusions: Subtrochanteric fractures caused by low-energy trauma have similar prognosis to other proximal femoral fractures. Trochanteric-entry cephalomedullary nails are a versatile treatment option for these injuries, and are associated with an acceptable rate of peri-operative complications and favourable functional outcome


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 1 | Pages 68 - 75
1 Jan 2005
Miedel R Ponzer S Törnkvist H Söderqvist A Tidermark J

We studied 217 patients with an unstable trochanteric or subtrochanteric fracture who had been randomly allocated to treatment by either internal fixation with a standard Gamma nail (SGN) or a Medoff sliding plate (MSP, biaxial dynamisation mode). Their mean age was 84 years (65 to 99) and they were reviewed at four and 12 months after surgery. Assessments of outcome included general complications, technical failures, revision surgery, activities of daily living (ADL), hip function (Charnley score) and the health-related quality of life (HRQOL, EQ-5D).

The rate of technical failure in patients with unstable trochanteric fractures was 6.5% (6/93) (including intra-operative femoral fractures) in the SGN group and 5.2% (5/96) in the MSP group. In patients with subtrochanteric fractures, there were no failures in the SGN group (n = 16) and two in the MSP group (n = 12). In the SGN group, there were intra-operative femoral fractures in 2.8% (3/109) and no post-operative fractures. There was a reduced need for revision surgery in the SGN group compared with the MSP group (8.3%; 9/108; p = 0.072). The SGN group also showed a lower incidence of severe general complications (p < 0.05) and a trend towards a lower incidence of wound infections (p = 0.05). There were no differences between the groups regarding the outcome of ADL, hip function or the HRQOL. The reduction in the HRQOL (EQ-5Dindexscore) was significant in both groups compared with that before the fracture (p < 0.005).

Our findings indicate that the SGN showed good results in both trochanteric and subtrochanteric fractures. The limited number of intra-operative femoral fractures did not influence the outcome or the need for revision surgery. Moreover, the SGN group had a reduced number of serious general complications and wound infections compared with the MSP group. The MSP in the biaxial dynamisation mode had a low rate of failure in trochanteric fractures but an unacceptably high rate when used in the biaxial dynamisation mode in subtrochanteric fractures.

The negative influence of an unstable trochanteric or subtrochanteric fracture on the quality of life was significant regardless of the surgical method.


The Journal of Bone & Joint Surgery British Volume
Vol. 78-B, Issue 3 | Pages 387 - 390
1 May 1996
Lunsjö K Ceder L Stigsson L Hauggaard A

The Medoff sliding plate (MSP) is a new device used to treat intertrochanteric and subtrochanteric fractures. There are three options for sliding; either along the shaft or the neck of the femur, or a combination of both. In a prospective series of 108 consecutive displaced intertrochanteric fractures we used combined dynamic compression. The patients were followed clinically and radiologically for one year. All fractures healed during the follow-up period. The only postoperative technical failure was one lag-screw penetration. Combined compression of the MSP gives increased dynamic capacity which reduces the risk of complications. The low rate of technical failure in our series compares favourably with that of the sliding hip screw or the Gamma nail but randomised trials comparing the MSP with other hip screw systems are necessary to find the true role of the MSP with its various sliding modes


The Journal of Bone & Joint Surgery British Volume
Vol. 77-B, Issue 2 | Pages 277 - 283
1 Mar 1995
Choueka J Koval K Kummer F Crawford G Zuckerman J

We studied the biomechanical behaviour of three sliding fixation devices for trochanteric femoral fractures. These were a titanium alloy sideplate and lag screw, a titanium alloy sideplate and dome plunger with cement augmentation, and a stainless-steel sideplate and lag screw. We used 18 mildly osteoporotic cadaver femora, randomly assigned to one of the three fixation groups. Four displacement and two strain gauges were fixed to each specimen, and each femur was first tested intact (control), then as a two-part fracture and then as a four-part intertrochanteric fracture. A range of physiological loads was applied to determine load-bearing, load-sharing and head displacement. The four-part-fracture specimens were subsequently tested to failure to determine maximum fixation strengths and modes of failure. The dome-plunger group failed at a load 50% higher than that of the stainless-steel lag-screw group (p < 0.05) and at a load 20% higher than that of the titanium-alloy lag-screw group (NS). All 12 lag-screw specimens failed by cut-out through the femoral head or neck, but none of the dome-plunger group showed movement within the femoral head when tested to failure. Strain-gauge analysis showed that the dome plunger produced considerably less strain in the inferior neck and calcar region than either of the lag screws. Inferior displacement of the femoral head was greatest for the dome-plunger group, and was due to sliding of the plunger. The dome plunger with cement augmentation was able to support higher loads and did not fail by cut-out through the femoral head.(ABSTRACT TRUNCATED AT 250 WORDS)


The Journal of Bone & Joint Surgery British Volume
Vol. 54-B, Issue 3 | Pages 432 - 441
1 Aug 1972
Maudsley RH Chen SC

1. A modification of the McLaughlin technique of lag screw fixation of the fractured scaphoid is described. 2. Fifty-six patients operated upon between 1956 and 1966 have been reviewed and their fractures classified under the headings recent, delayed union and non-union. 3. Plaster casts were avoided and early return to work encouraged; 95 per cent did so within two months. 4. Of twenty-two recent fractures, including three perilunar trans-scaphoid dislocations, nineteen united; of fifteen showing delayed union, eight united: and of nineteen cases of non-union, only two united. 5. The function of the wrist in the seventeen cases of persistent non-union stabilised by lag-screw was surprisingly good; only one patient has required arthrodesis to date. 6. The indications and contra-indications for the operation are discussed


The Journal of Bone & Joint Surgery British Volume
Vol. 39-B, Issue 3 | Pages 477 - 486
1 Aug 1957
McKee GK

A method of intra-articular arthrodesis of the hip is described in which fixation is obtained with a lag-screw. Two main advantages are claimed: first, that it is a compression arthrodesis and gives early bony fusion; and second, that it gives adequate internal fixation in most cases so that the disadvantages of a plaster hip spica are avoided, and the patient may walk with crutches two or three weeks after the operation. The results were satisfactory in forty-seven of the first fifty cases in which this method of arthrodesis was employed. There were two post-operative deaths and one failure to secure fusion in a case of massive necrosis of the femoral head