Objectives. Because of the contradictory body of evidence related to the potential benefits of helical blades in trochanteric fracture fixation, we studied the effect of bone compaction resulting from the insertion of a proximal femoral nail anti-rotation (PFNA). . Methods. We developed a subject-specific computational model of a trochanteric fracture (31-A2 in the AO classification) with lack of medial support and varied the bone density to account for variability in bone properties among hip fracture patients. Results. We show that for a bone density corresponding to 100% of the bone density of the cadaveric femur, there does not seem to be any advantage in using a PFNA with respect to the risk of blade cut-out. On the other hand, in a more osteoporotic femoral head characterised by a density corresponding to 75% of the initial bone density, local bone compaction around the helical blade provides additional bone purchase, thereby decreasing the risk of cut-out, as quantified by the volume of bone susceptible to yielding. Conclusions. Our findings indicate benefits of using a PFNA over an intramedullary nail with a conventional lag screw and suggest that any clinical trial reporting surgical outcomes regarding the use of helical blades should include a measure of the femoral head bone density as a covariable

Aims. Proximal femur fractures treatment can involve anterograde nailing with a single or double cephalic screw. An undesirable failure for this fixation is screw cut-out. In a single-screw nail, a tip-apex distance (TAD) greater than 25 mm has been associated with an increased risk of cut-out. The aim of the study was to examine the role of TAD as a risk factor in a cephalic double-screw nail. Methods. A retrospective study was conducted on 112 patients treated for intertrochanteric femur fracture with a double proximal screw nail (Endovis BA2; EBA2) from January to September 2021. The analyzed variables were age, sex, BMI, comorbidities, fracture type, side, time of surgery, quality of reduction, pre-existing therapy with bisphosphonate for osteoporosis, screw placement in two different views, and TAD. The last follow-up was at 12 months. Logistic regression was used to study the potential factors of screw cut-out, and receiver operating characteristic curve to identify the threshold value. Results. A total of 98 of the 112 patients met the inclusion criteria. Overall, 65 patients were female (66.3%), the mean age was 83.23 years (SD 7.07), and the mean follow-up was 378 days (SD 36). Cut-out was observed in five patients (5.10%). The variables identified by univariate analysis with p < 0.05 were included in the multivariate logistic regression model were screw placement and TAD. The TAD was significant with an odds ratio (OR) 5.03 (p = 0.012) as the screw placement with an OR 4.35 (p = 0.043) in the anteroposterior view, and OR 10.61 (p = 0.037) in the lateral view. The TAD threshold value identified was 29.50 mm. Conclusion. Our study confirmed the risk factors for cut-out in the double-screw nail are comparable to those in the single screw. We found a TAD value of 29.50 mm to be associated with a risk of cut-out in double-screw nails, when good fracture reduction is granted. This value is higher than the one reported with single-screw nails. Therefore, we suggest the role of TAD should be reconsidered in well-reduced fractures treated with double-screw intramedullary nail. Cite this article: Bone Jt Open 2024;5(6):457–463

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

This study compares outcomes of fixation of subtrochanteric femoral fractures using a single lag screw (Gamma3 nail, GN) with a dual lag screw device (InterTAN nail, IN). The primary outcome was mechanical failure, defined as lag screw cut-out, back-out, nail breakage or peri-implant fracture. Technical factors associated with mechanical failure were also identified. All adult patients (>18yrs) with a subtrochanteric femoral fracture treated in a single centre were retrospectively identified using electronic records. Included patients underwent surgical fixation using either a long GN (2010–2017) or IN (2017–2022). Cox regression analysis was used to determine the risk of mechanical failure and technical predictors of failure. The study included 587 patients, 336 in the GN group (median age 82yrs, 73% female) and 251 in the IN group (median age 82yrs, 71% female). The IN group exhibited a higher prevalence of osteoporosis (p=0.002) and CKD□3 (p=0.007). There were no other baseline differences between groups. The risk of any mechanical failure was increased two-fold in the GN group (HR 2.51, p=0.020). Mechanical failure comprising screw cut-out (p=0.040), back-out (p=0.040) and nail breakage (p=0.51) was only observed in the GN group. The risk of peri-implant fracture was similar between the groups (HR 1.10, p=0.84). Technical predictors of mechanical included varus >5° for cut-out (HR 15.61, p=0.016), TAD>25mm for back-out (HR 9.41, p=0.020) and shortening >1cm for peri-implant fracture (HR 6.50, p=<0.001). Dual lag screw designs may reduce the risk of mechanical complications for patients with subtrochanteric femoral fractures

The augmentation of fixation with bone cement is increasingly being used in the treatment of severe osteoporotic fractures. We investigated the influence of bone quality on the mechanics of augmentation of plate fixation in a distal femoral fracture model (AO 33 A3 type). Eight osteoporotic and eight non-osteoporotic femoral models were randomly assigned to either an augmented or a non-augmented group. Fixation was performed using a locking compression plate. In the augmented group additionally 1 ml of bone cement was injected into the screw hole before insertion of the screw. Biomechanical testing was performed in axial sinusoidal loading. Augmentation significantly reduced the cut-out distance in the osteoporotic models by about 67% (non-augmented mean 0.30 mm (. sd. 0.08) vs augmented 0.13 mm (. sd. 0.06); p = 0.017). There was no statistical reduction in this distance following augmentation in the non-osteoporotic models (non-augmented mean 0.15 mm (. sd. 0.02) vs augmented 0.15 mm (. sd. 0.07); p = 0.915). In the osteoporotic models, augmentation significantly increased stability (p = 0.017). Cite this article: Bone Joint J 2013;95-B:1406–9

We investigated a new intramedullary locking nail that allows the distal interlocking screws to be locked to the nail. We compared fixation using this new implant with fixation using either a conventional nail or a locking plate in a laboratory simulation of an osteoporotic fracture of the distal femur. A total of 15 human cadaver femora were used to simulate an AO 33-A3 fracture pattern. Paired specimens compared fixation using either a locking or non-locking retrograde nail, and using either a locking retrograde nail or a locking plate. The constructs underwent cyclical loading to simulate single-leg stance up to 125 000 cycles. Axial and torsional stiffness and displacement, cycles to failure and modes of failure were recorded for each specimen. When compared with locking plate constructs, locking nail constructs had significantly longer mean fatigue life (75 800 cycles (. sd. 33 900) vs 12 800 cycles (. sd. 6100); p = 0.007) and mean axial stiffness (220 N/mm (. sd. 80) vs 70 N/mm (. sd. 18); p = 0.005), but lower mean torsional stiffness (2.5 Nm/° (. sd. 0.9) vs 5.1 Nm/° (. sd. 1.5); p = 0.008). In addition, in the nail group the mode of failure was either cut-out of the distal screws or breakage of nails, and in the locking plate group breakage of the plate was always the mode of failure. Locking nail constructs had significantly longer mean fatigue life than non-locking nail constructs (78 900 cycles (. sd. 25 600) vs 52 400 cycles (. sd. 22 500); p = 0.04). The new locking retrograde femoral nail showed better stiffness and fatigue life than locking plates, and superior fatigue life to non-locking nails, which may be advantageous in elderly patients. Cite this article: Bone Joint J 2014;96-B:114–21

Aims

To evaluate if, for orthopaedic trainees, additional cadaveric simulation training or standard training alone yields superior radiological and clinical outcomes in patients undergoing dynamic hip screw (DHS) fixation or hemiarthroplasty for hip fracture.

Introduction. Unstable intertrochanteric hip fractures (AO 31A2) continue to be a challenge, as non-locking implants have shown a considerable rate of loss of reduction. Intramedullary fixation has been recommended, although screw cut-out has been identified as problematic. This study was performed to ascertain whether treatments with the established proximal femoral nail (PFN) and the newer PFNA with blade design (proximal femoral nail antirotation) have advantages over the use of the Percutaneous Compression Plate (PCCP, developed by Gotfried). Methods. Cohort study. Between March 2003 and March 2008, 134 patients with unstable fractures were treated with a PCCP, (n=44, 78.3 yrs, ASA 2.8), a PFN (n=50, 77.2 yrs, ASA 2.8), or a PFNA (n=40, 75.8 yrs, ASA 2.6). The patients (31 PCCP, 33 PFN, 30 PFNA) were then reexamined clinically and radiologically after approximately 21 months. Results. The PCCP was found to require less implantation time than the PFN and the PFNA (60 vs. 80 vs. 84 min, p<0.001) and less radiation exposition time (PCCP 139 vs. PFN 283 vs. PFNA 188 seconds, p<0.001). The rate of reoperations due to wound infections and hematomas amounted to 2% for the PCCP, 4% for the PFN, and 5% for the PFNA (p=0.799). Due to mechanical complications, 9% of patients implanted with a PCCP, 13% of those implanted with a PFN, and 5% of those implanted with a PFNA had to be reoperated (p=0.353). The cut-out rate was 2% after implantation of the PCCP, 4% after the PFN, and 5% after implantation of the PFNA (p=0.799). In one case, the shaft was fractured intraoperatively (PFNA). The tip-apex distance for the lower femoral neck screw (PCCP 22mm vs. PFN 30mm vs. PFNA 30mm, p<0.001), stress-related varisation of the collodiaphyseal (CCD) angle (4° for all implants), impaction (PCCP 5mm vs. PFN 5mm vs. PFNA 6mm, p=0.662) and femoral shortening (PCCP 3mm vs. PFN 3mm vs. PFNA 4mm, p=0.876) were not determinants of the postoperative function. On the basis of their scores according to Merle d'Aubigné and Harris, there was no variation in the results of the follow-up examinations. Conclusions. The use of the PCCP for the treatment of unstable trochanteric fractures presents a minimally invasive method of implantation, as well as a promising therapy option with regards to operation time, radiologic examination time, and rate of complications. Processes of impaction due to stress are seldom observed. No benefits could be established in an intramedullary treatment with the PFN or the PFNA; thus, it appears that the higher cost of these implants is avoidable

Introduction. The most common treatment options for fixation of osteoporotic distal femur fractures are retrograde nails and locking plates. There are proponents of more elastic titanium plates as well as more rigid steel plates; No clear superiority of one over the other has been established. We aimed to evaluate the mechanical differences between stainless steel and titanium locking plates in the fixation of distal femur fractures in osteoporotic bone. We hypothesized that due to its higher elasticity titanium locking plates can absorb more energy and are therefore less likely to “cut” into the bone compared to stainless steel locking plates resulting in improved metaphyseal osteoporotic fracture fixation. Methods. We used eight matched pairs of osteoporotic fresh-frozen human cadaveric femurs (age >70 years, all female). Within each pair we randomized one femur to be fitted with a Less Invasive Stabilization System (LISS-Titanium locking plate) and one with a Distal Locking Condylar Plate (DLCP-Stainless steel locking plate). A fracture model simulating an AO 33-A3 fracture was created (extraarticular comminuted fracture) and specimens were subsequently subjected to step-wise cyclic axial loading to failure. We used an advanced three dimensional tracking system (Polhemus Fastrak) to monitor the movement of the distal fragment relative to the real time distal plate position allowing us to evaluate distal implant cut-out. Results. During cyclic testing, seven of the eight pairs of matched femurs, the DLCP failed before the LISS plate (p=0.03). All constructs were able to withstand cyclical loading up to 800N. The overall plastic deformation as measured by the displacement of the Instron crosshead experienced by the titanium plate constructs was significantly lower compared to the stainless steel plate construct: The plastic deformation of the LISS plates was 39% lower compared to the Locking Condylar plates after cycle testing at 400 Newtons and 70% lower at 800N. Furthermore during the 800N cycle testing the LISS plating system showed a significantly lower rate of plastic deformation not only for the entire bone-implant construct, but also between the plate and the distal fragment than the locking condylar plate (=less distal implant cut-out). Conclusions. The use of a more advanced three dimensional tracking system, fresh-frozen osteoporotic matched human specimen and the ability to test all constructs to failure allowed us a more thorough comparison of titanium versus stainless steel implants compared to previous studies. The titanium locking plates provided an overall superior fixation of osteoporotic distal femur fractures with less distal implant cut-out, a better elastic recoil, and a slower rate of residual plastic deformation

Introduction. The sliding hip screw is the implant of choice for the operative treatment of stable trochanteric femur fractures. Surgeons have been using widely the four-hole side plate DHS (Dynamic Hip screw) with four bicortical screws, which allows adequate weight bearing after operation. However, there is lacking of scientific studies that support the use of such long plate and we question ourselves if we can accomplish the same results with the use of a smaller plate. The objective of this study is to compare the results accomplished with a four-hole and a two-hole DHS side plate in the treatment of transtrochanteric fractures. Material and Methods. This study included 140 patients (43 male and 97 female) that had stable transtrochanteric fractures between 1/01/2005 and 31/12/2008 and were submitted to osteossynthesis with DHS side-plate. 32 (22.9%) were treated with a two-hole DHS (group DHS2) and 108 (77.1%) with four-hole. The fractures were evaluated according to the AO/OTA classification and Evans for stability. The fracture reduction was assessed according to Sernbo criteria and was recorded also patient demographics, fracture patterns and fixation, comorbilities, mortality rate, capacity of ambulation and complications. Results. The patients had in medium 77.74 ± 49.52 years and 18 months of follow-up (range 6–36 months). Both groups had similar patient demographics. The etiology of the fracture was fall in 120 (85.7%) and 20 (14.3%) from traffic accident, 10 (7.1%) were patological. 15 (10.7%) died during hospital stay: 13 (12.0%) in DHS4 group and 2 (6.3%) in DHS2. In terms of capacity of ambulation in the group DHS2 15.6% didn't ambulate and 25% had walking aid; in the group DHS4 20.4% didn't ambulate and 29.7% had walking aid. Concerning fracture reduction there was varus (<125°) in 9.4% of DHS2 group and 9.3% in DHS4. Also in the group DHS4 there were 15 (13.9%) complications: 3 cut-out, 3 device failure, 8 infections and 1 pseudarthrosis. In the group DHS2 there were 4 (12.5%) complications: 1 cut-out, 2 infections and 1 device failure. 121 (28 group DHS2 and 93 group DHS4) fractures healed without complications in anatomical position with good function of the hip joint. Discussion. We found no significant differences between the two groups regarding reduction or percentage of complications. However we could observe that in the group DHS2 there was a lesser rate of mortality during hospital stay and a higher capacity of ambulation without walking aid. So the fixation of stable transtrochanteric fractures with a two-hole DHS side-plate is safe, less invasive, less surgical time and less blood loss than a four-hole. As our study reveled in these stable fractures there is lacking of benefit with the use of a larger slide-plate, the two-hole is adequate and its use should be increasing in our clinical practice

Aims

The aim of this study was to investigate if there are differences in outcome between sliding hip screws (SHSs) and intramedullary nails (IMNs) with regard to fracture stability.

The treatment for trochanteric femoral fractures is still challenging. Since 2005, we are using 2 new implants: Gamma3™ nail and the PFN-A™. All patients with a fracture of the trochanteric area were included in an observational study during 3 years. Objectives were radiographics and clinics (complications) comparaison of these 2 new devices. We included 426 patients (236 Gamma3™ nails, 190 PFN-A™). We faced the epidemiological data, per and post-operative complications. The tip-apex distance and the position of the cephalic implant were studied. The 2 implants were well positionned in more than 80%, with no statistic diffferencie. We found a a cut-out rate of 1,4 % and a re-operation rate of 4,9 %. These rates of usual complications are very low in comparaison with litterature. We did not found a statistic difference between these 2 differents nails. But, we observed 2 unusual complications: for the Gamma3™ nail, a high rate of automatic distal locking failure, and for the PFN-A™, many patients complained of thigh pain resulting from a prominent cephalic blade. These 2 new complications can be avoided by small changes in the operative procedure. In our mind these 2 implants can be used for treating all patients with trochanteric fracture, but we need other studies to compare these nails with the new generation of sliding plate

Aims

Postoperative malalignment of the femur is one of the main complications in distal femur fractures. Few papers have investigated the impact of intraoperative malalignment on postoperative function and bone healing outcomes. The aim of this study was to investigate how intraoperative fracture malalignment affects postoperative bone healing and functional outcomes.

PURPOSE. To evaluate the late radiographic and functional complications occurring after treatment of reverse oblique trochanteric fractures with the proximal femoral nail. PATIENTS. This is a retrospective study which was conducted between October 2004 and October 2009. 55 patients with a reverse oblique trochanteric fracture were treated with the Gamma 3 nail. According to the AO classification, there were 36 type AIII-1, 8 AIII-2, 11 AIII-3 fractures. Closed reduction was achieved in all patients. The long gamma 3 nail was used in 34 fractures. The mean follow up was 18 months (range 9 to 32 months). The patients were evaluated clinically (Harris hip score) and radiographically. RESULTS. No intraoperative complications were recorded. During surgery, satisfactory reduction and acceptable nail insertion was assessed in all patients. No early postoperative technical failures were noticed. Complete union was achieved in 51 patients. The mean Harris hip score was 80.2. The results were excellent in 23 patients (41.8%), good in 19 (34.5%), fair in 9 (16.3%), and poor in 4 patients (7%). Late radiographic complications included secondary varus displacement due to cut-out of the proximal screw in three patients (5.4%), and calcification at the tip of the greater trochanter in nine patients (16%). Stress shielding as evidenced by the lack of cortical hypertrophy at the level of the tip of the implant were detected in 5 patients. Patients treated with a long gamma 3 nail achieved a statistically significant better result (p< 0.005). Three patients (5.5%) required a reconstructive procedure. CONCLUSION. Proximal femoral nailing provides stronger fixation of the proximal part in reverse oblique trochanteric fractures reducing mechanical complications. The implant choice, the accuracy of fracture reduction, and the correct placement of the nail are the key factors influencing the final outcome

We compared the results of the surgical treatment of trochanteric hip fractures before and after surgeons had been introduced to the tip-apex distance (TAD) as a method of evaluating screw position. There were 198 fractures evaluated retrospectively and 118 after instruction. The TAD is the sum of the distance from the tip of the screw to the apex of the femoral head on antero-posterior and lateral views. This decreased from a mean of 25 mm in the control group to 20 mm in the study group (p = 0.0001). The number of mechanical failures by cut-out of the screw from the head decreased from 16 (8%) in the control group at a mean of 13 months to none in the study group at a mean of eight months (p = 0.0015). There were significantly fewer poor reductions in the study group. Our study confirms the importance of good surgical technique in the treatment of trochanteric fractures and supports the concept of the TAD as a clinically useful way of describing the position of the screw

Hip fracture treatment strategies continue to evolve with the goal of restoring hip fracture victims to Pre-injury Functional levels. Strategies for improved treatment have focused on fracture exposure, reduction, provisional fixation and definitive fixation with implant designs optimised for fracture union with minimal implant failure as originally proposed by Lambotte. Multiple implant designs have been conceived based on perceived inadequacies of previous generational designs. To better understand this evolutionary process, it is necessary to review the predecessors of modern fracture treatment and understand their design concepts and results. It is interesting that the modern era of surgical treatment of hip fractures actually began in 1902, when Dr Royal Whitman advocated the necessity of a closed reduction of adult hip fractures under general anesthesia and stabilisation by hip spica cast. Dr Whitman predicted the evolution of stabilisation by internal fixation and commented on this in his 1932 JBJS editorial emphasising the importance of surgical treatment of fractures. Dr Smith-Peterson, also from New York, in 1925 developed the 1st commercially successful hip implant, a tri–flanged nail. These first surgeries were performed with an open reduction, through a Smith-Petersen approach without radiographic control. This nail device was rapidly modified in the 1930's to permit insertion over a guide wire with a radiographic controlled insertion technique, a minimally invasive procedure. Nail penetration and implant failure in pertrochanteric fractures led to the rapid development of side-plates and a refocus on reduction stability. This led to a period of primary corrective osteotomies for enhanced stability, but fell out of failure after the sliding hip screw concept took hold. Originally conceived by Godoy-Moreira and Pohl independently in the 1940s, it became rapidly accepted as a method to avoid nail penetration and implant failure, unfortunately at the expense of accepting malunion and collapse of the fracture. Even the importance of rotational stability was discarded as insignificant by Holt in 1963. The concept of reduction of the Antero-Medial cortex was forgotten in favour of the Tip-apex distance as the only important variable in reduction to avoid implant cut-out. The concept of malunion of pertrochanteric fractures was simply deleted from consideration with disregard for the possible association of impaired functional recovery. Several recent papers that improved functional recovery is possible when these new implants are coupled with successful reduction strategies. Further studies are needed to identify the correct choice of implant for the appropriate fracture configuration, which may lead to a revision of our current fracture classification systems and our concepts of stability

Introduction. Significant access morbidity with intercostal neuralgia and post-thoracotomy pain syndrome was reported in case that an anterior approach for spondylodesis of fractures of the thoracolumbar spine was used. We describe our experience with thoracoscopical fusion from anterior as a less invasive approach. Patients. Between 02/2007 and 09/2008 in a series of 32 patients (18 male; mean age 43, 17–74yrs) with fractures of the thoracolumbar spine (level Th11: n = 2, level Th12: n = 12, level L1: n = 18; fracture types: A3.1.1: n = 15, A3.2.1: n = 11, A3.3.1: n = 3, B2.1: n = 1 and B2.3: n = 2) thoracoscopical fracture stabilization was performed. A less invasive approach with three portals without an assistant was used facilitated by a new retractor system. In 16 patients fracture stabilization from anterior was supported by an additional spondylodesis using an dorsal approach. For reconstruction of the anterior column a VLIFT-system (n = 19), a Synex- (n = 11) or a Harms-Cage (n = 2) in combination with a MACS-TL (n = 16) or a Arcofix-system (n = 2) were used. Results. Thoracoscopical fusion from anterior was performed about 8 days after the injury (1–73 days), monosegmental in 11 and bisegmental in 21 out of 32 cases. The mean overall operating time was 201min (range 105–380min). The mean overall blood loss was 780ml, in 3/32 patients blood transfusions were required. In one patient epidural bleeding and in another a screw cut-out of the MACS system of the first lumbar vertebral body occurred intraoperatively. Revision surgery was necessary due to failure of the hardware (n = 2) or occurrence of hematothorax (n = 1). In the further follow up period no wound healing disorders, failure of the implants nor intercostal neuralgia were noted. Discussion. The endoscopic view is two-dimensional and may disorientate the less experienced surgeon, and thus, prolong operation time. However, the use of a retractor system allowed for bimanual operation increasing the depth perception, provided an optimal illuminated, and permanent and stable operation field, and was economic as an assistant was not required. Conclusion. The presented technique is a high demanding approach for anterior fusion of fractures of the thoracolumbar spine, however, with the potential to reduce the surgical access trauma to a minimum with an operation time comparable to open surgery. Patients might benefit from a shortened rehabilitation and a early reintegration into professional life

Aims

The primary aim of this study was to determine if delayed clavicular fixation results in a greater risk of operative complications and revision surgery.

Objectives

External fixators are the traditional fixation method of choice for contaminated open fractures. However, patient acceptance is low due to the high profile and therefore physical burden of the constructs. An externalised locking compression plate is a low profile alternative. However, the biomechanical differences have not been assessed. The objective of this study was to evaluate the axial and torsional stiffness of the externalised titanium locking compression plate (ET-LCP), the externalised stainless steel locking compression plate (ESS-LCP) and the unilateral external fixator (UEF).

The spiral blade modification of the Dynamic Hip Screw (DHS) was designed for superior biomechanical fixation in the osteoporotic femoral head. Our objective was to compare clinical outcomes and in particular the incidence of loss of fixation.

In a series of 197 consecutive patients over the age of 50 years treated with DHS-blades (blades) and 242 patients treated with conventional DHS (screw) for AO/OTA 31.A1 or A2 intertrochanteric fractures were identified from a prospectively compiled database in a level 1 trauma centre. Using propensity score matching, two groups comprising 177 matched patients were compiled and radiological and clinical outcomes compared. In each group there were 66 males and 111 females. Mean age was 83.6 (54 to 100) for the conventional DHS group and 83.8 (52 to 101) for the blade group.

Loss of fixation occurred in two blades and 13 DHSs. None of the blades had observable migration while nine DHSs had gross migration within the femoral head before the fracture healed. There were two versus four implant cut-outs respectively and one side plate pull-out in the DHS group. There was no significant difference in mortality and eventual walking ability between the groups. Multiple logistic regression suggested that poor reduction (odds ratio (OR) 11.49, 95% confidence intervals (CI) 1.45 to 90.9, p = 0.021) and fixation by DHS (OR 15.85, 95%CI 2.50 to 100.3, p = 0.003) were independent predictors of loss of fixation.

The spiral blade design may decrease the risk of implant migration in the femoral head but does not reduce the incidence of cut-out and reoperation. Reduction of the fracture is of paramount importance since poor reduction was an independent predictor for loss of fixation regardless of the implant being used.

Cite this article: Bone Joint J 2015;97-B:398–404.