Nail Failure Research Articles

Exchange nailing for femoral diaphyseal fracture non-unions: Risk factors for failure.

The aim of this study was to identify risk factors for failure of exchange nailing for femoral diaphyseal fracture non-unions. The study cohort comprised 40 patients with femoral diaphyseal non-unions treated by exchange nailing, of which six were open injuries. The median time to exchange nailing from primary fixation was 8.4 months. The main outcome measures were union, number of secondary fixation procedures required to achieve union and time to union. Multiple causes for non-union were found in 16 (40%) cases, with infection present in 12 (30.0%) patients. Further surgical procedures were required in nine (22.5%) cases, one of whom (2.5%) required the use of another fixation modality to achieve union. Union was ultimately achieved with exchange nailing in 34/37 (91.9%) patients. The median time to union after the exchange nailing was 9.4 months. Cigarette smoking and infection were risk factors for failure of exchange nailing. Multivariate analysis found infection to be the strongest predictor of exchange failure (p<0.05). Exchange nailing is an effective treatment for aseptic femoral diaphyseal fracture non-union. However, 50% of patients undergoing exchange nailing in the presence of infection required at least one further procedure. It is important to counsel patients of this so that they can plan for it and do not consider that the first exchange operation has failed.

Performance of a 2-Story CLT House Subjected to Lateral Loads

AbstractA 2-story full-scale model of a cross-laminated timber (CLT) house was tested under quasi-static monotonic and cyclic loading. The primary objectives were to investigate 3D system performance of a CLT structure subjected to lateral loads in terms of lateral strength and deformability capacity, global behavior of the structure, frequency response of the structure before and after each test, and performance of anchoring connectors (hold-downs, brackets) and connections between CLT panels. The house was 6.0×4.8 m in plan with a height of 4.8 m. A total of five (one push-over and four cyclic) quasi-static tests were performed, one direction at a time. Parameters, such as the direction of loading, number of hold-downs, and number of screws in perpendicular wall-to-wall connections, were varied in the tests. The CLT structure performed according to the design objectives, with the ultimate resistance being almost identical in both directions. Failure mechanisms, i.e., shear failure of nails in the brack...

The humelock hemiarthoplasty device for both primary and failed management of proximal humerus fractures: a case series.

Fractures of the proximal humerus account for 4-5% of all fractures. Managing proximal humerus fractures operatively and non-operatively have their respective complications both short- and long-term. We present our experience using the Humelock hemiarthoplasty device for both primary and failed management of proximal humeral fractures. We present four different examples from ten cases that include a failure of internal fixation, a failure of intramedullary nailing, a complex case in a patient with multiple co-morbidities, and a failure of nonoperative management. The patients in our series had multiple injuries and the device allowed early mobilization and produced good results. We suggest that this device has a role in the failure of primary and secondary management of proximal humeral fractures in a district general hospital setting.

Failure behavior and mechanism of slopes reinforced using soil nail wall under various loading conditions

Soil–nailing technology is widely applied in practice for reinforcing slopes. A series of centrifuge model tests was conducted on slopes reinforced with a soil nail wall under three types of loading conditions. The behavior and mechanism of failure process of the reinforced slopes were studied using image-based observation and displacement measurements for the slope, nails, and cement layer. The nailing significantly increased the stability level and restricted the tension cracks of the slopes. Increasing the nail length improved the stability of the reinforced slopes with deeper slip surfaces. The reinforced slope exhibited a significant failure process, in which slope slippage failure and cement layer fracture occurred in conjunction with a coupling effect. The deformation localization was induced by the loading within the slope and ultimately developed into a slip surface. The nailing reinforced the slope by significantly delaying the occurrence of the deformation localization within the slope. The failure of nails was recognized as a combination of pull-out failure and bend deformation. The loading conditions were shown to have a significant effect on slope deformation and nail deflection, and they consequently influenced the failure behavior and its formation sequence.

Retrograde reamed femoral nailing.

Closed, reamed, antegrade nailing remains the standard of care for femoral shaft fractures. This technique however, may be less attractive in the management of femoral shaft fractures associated with (a) ipsilateral acetabular, pelvis, or femoral neck fractures; (b) poly trauma requiring multiple simultaneous surgical procedures; and (c) pregnancy. We now report on our experience with the retrograde femoral nailing as a treatment option in these situations. Between 4/88 and 10/90, 29 retrograde femoral nailing in 24 patients were attempted. Average age was 29.3 (16-74) years. Five fractures were open. Fracture location was isthmal in 14 and infraisthmal in 15. The comminution was classified according to Winquist and Hansen: I(10), II(7), III(7), and IV(5). Nailing was possible in 28/29 cases. Insertion was made through an extraarticular medial condylar portal. Nail diameter ranged from 10 to 13 mm. An AO Universal Femoral Nail was used in the first 11 cases; all subsequent fractures were stabilized using an AO Universal Tibial Nail because its design appeared better suited to this technique. Follow-up was possible for 25 fractures in 21 patients and averaged 16.0 (range, 11-27); months 23/25 (92%) fractures healed within 12 weeks. No case was associated with an infection, loss of reduction, or nail failure. Knee flexion averaged 122°; only two knees had an extensor lag of >5°. Intraoperative complications included three cases of crack propagation at the insertion site, and four infraisthmal malreductions (two valgus, two flexion). Based on these results, we feel that retrograde reamed femoral nailing is a suitable alternative to antegrade nailing and should be considered in situations where proximal access is neither possible nor desirable.

Rush nail and management of fracture both bone forearm

Background: The failure of the conventional nailing of both bone of the forearm poses a potential problem of nail migration and rotational instability, despite the best reduction. Objectives: Rush nail is a very handy, low cost easily available implant. In the present study, we have tried to find out its applicability if used in the closed manner under C-arm control without injurying soft tissues and preserving the periosteal vascularity. Materials and Methods: This prospective study was conducted on thirty adult subjects. Skeletally mature subjects with Gustilo type 1 open and closed fractures without the neurovascular deficit were included. Stainless steel rush nails were used for all patients for both radius and ulnar repair. Patients were followed-up for a minimum of 4 months and maximum of 1.5 years. Results: The mean age of study participants was 37.43 years. Mean time of the union was 14.32 weeks. Average operative time was 67.16 min. No intraoperative complication occurred nor was any nailing converted to some other form of fixation, except in three cases radial nail was introduced by open method through anterior Henry's approach. Cast support was maintained for a mean of 7.43 weeks, after that forearm brace was applied for a mean period of 6.26 weeks and continued until radiographic union was seen. Three patients showed non-union of radius mostly distal third. They were treated with open reduction and internal fixation with locking plate and bone grafting. One patient had extensor tendon injury. Two patients have superficial infection which cured with antibiotics. One case had delayed union of radius which required bone grafting. Two patients had gross restrictions of wrist movements and pronation-supination movement. Using Anderson criteria 22 patients had satisfactory results (71.33%), three patients had excellent result. Three patients had non-unions (10%). Implant removal was performed in two cases about 14 months post-operatively and no refracture has been reported until date (after 4 months). Conclusion: Use of rush nail continues to have predictable and good results. Complication rates are lower when compared to plate osteosynthesis and even in locked intramedullary nails although application of above elbow cast after nailing is a downside of this procedure. The rush nail has still a future in repair of forearm fractures considering its low complications rates, cost and acceptable results in a developing country where financial matters are to be considered.

Femoral Lengthening Over a Pediatric Femoral Nail

Limb lengthening by callotasis as described by Ilizarov has become the standard method of lower extremity lengthening. Lengthening over an intramedullary nail to allow early removal of the external fixator has also become common in adults but few studies have addressed the efficacy in children. A retrospective review of 37 consecutive children who had undergone femoral lengthening with external fixator over an intramedullary nail was performed. Charts were reviewed for demographics, surgical details, and complications. Radiographs were examined to determine magnitude of lengthening and to calculate lengthening index. The average age of the 37 patients was 11.6 years (range, 8.1 to 17.0). The amount of lengthening averaged 7.0 cm (range, 3.0 to 11.4 cm), which represented a mean 20.4% increase in length. The mean time in the fixator was 81 days. The lengthening index was 1.21 days/mm. Thirteen patients developed major complications (37.8%) including 4 limbs that failed to lengthen initially, 3 fractures (1 before fixator removal and 3 after fixator removal), 2 nail failures, 4 deep infections, and 2 joint subluxations requiring operative care. The 3 fractures after fixator removal were treated with exchange nailing as were the 2 intramedullary nail failures. Four patients (10.8%) developed deep infections requiring irrigation, debridement, and IV antibiotics. One patient developed a late hip subluxation, which was treated with a shelf osteotomy but resulted in pain and limitation of motion. One patient developed knee subluxation during lengthening requiring operative intervention. The technique was successful in obtaining a good result with a functional lengthened femur without unresolved problems in 94% of the patients despite a significant rate of major complications, particularly in those with a congenital etiology. Only 2 of the 37 patients ultimately had results that were ultimately compromised by complications. Femoral lengthening over an intramedullary nail with the aid of an external fixator has shown to be an effective method for correcting limb length discrepancy. The technique has a high complication rate similar to other methods of lengthening. Level IV-Case Series.

Dynamic responses of nailed plywood-timber joints under a band-limited white-noise wave

In this study, dynamic tests of nailed plywood-timber joints are conducted under a band-limited white-noise wave using a uniaxial hydraulic shaking table. The principal results are as follows: dynamic responses of nailed plywood-timber joints under a band-limited white-noise wave are reasonably related to the static load-slip relationships and the dynamic responses under harmonic waves of them. When nailed plywood-timber joints are shaken under a composite wave of wide frequency range, they resonate transitionally with one of the frequency components one after another decreasing their equivalent resonant frequencies along their static load-slip curves. Nailed plywood-timber joints are in danger of ultimate failures even though the input maximum accelerations do not exceed their damage limits, if they are shaken for long times with or without intermittences. In this case, nailed plywood-timber joints are prone to fail in low-cyclic bending fatigue failure of nails. Nailed plywood-timber joints, on the other hand, are prone to fail in typical static failure modes when they are shaken under strong input maximum accelerations equivalent to their ultimate limits.

Inadequate ‘three-point’ proximal fixation predicts failure of the Gamma nail

The Gamma nail is frequently used in unstable peri-trochanteric hip fractures. We hypothesised that mechanical failure of the Gamma nail was associated with inadequate proximal three-point fixation. We identified a consecutive series of 299 Gamma nails implanted in 299 patients over a five-year period, 223 of whom fulfilled our inclusion criteria for investigation. The series included 61 men and 162 women with a mean age of 81 years (20 to 101). Their fractures were classified according to the Modified Evans' classification and the quality of fracture reduction was graded. The technical adequacy of three points of proximal fixation was recorded from intra-operative fluoroscopic images, and technical inadequacy for each point was defined. All patients were followed to final follow-up and mechanical failures were identified. A multivariate statistical analysis was performed, adjusting for confounders. A total of 16 failures (7.2%) were identified. The position of the lag screw relative to the lateral cortex was the most important point of proximal fixation, and when inadequate the failure rate was 25.8% (eight of 31: odds ratio 7.5 (95% confidence interval 2.5 to 22.7), p < 0.001). Mechanical failure of the Gamma nail in peri-trochanteric femoral fractures is rare (< 1%) when three-point proximal fixation is achieved. However, when proximal fixation is inadequate, failure rates increase. The strongest predictor of failure is positioning the lateral end of the lag screw short of the lateral cortex. Adherence to simple technical points minimises the risk of fixation failure in this vulnerable patient group.

Indications and outcomes of augmentation plating with decortication and autogenous bone grafting for femoral shaft nonunions

IntroductionThough augmentation plating (AP) with decortication and bone grafting (BG) reportedly has excellent outcomes for femoral shaft nonunions, there are no established indications of AP with decortication and BG. The purpose of this study was to evaluate the results of AP with decortication and autogenous BG for femoral shaft nonunions, focussing on the indications of AP with decortication and BG. MethodsThirty-nine patients treated with AP combined with decortication and BG for femoral shaft nonunions after femoral nail failure between November 1996 and October 2010 were retrospectively reviewed. Indications of AP with decortication and BG at the time of surgery and outcomes (bony union) were evaluated. ResultsThe mean follow-up duration was 24.8 months (range 12–81 months). Thirty-eight (97%) of 39 femoral shaft nonunions achieved bony union. One incompliant patient showed screw breakage, which was healed uneventfully with subsequent cast application. The mean time to union was 6.1 months (range 3–16 months). Primary indications at the time of surgery were nonisthmal femoral nonunions in 17 patients, isthmal nonunions in 10 patients (cortical bone defect in five and widened canal in five), failed exchange nail in seven patients, nonunions with malrotation in two patients and difficult removal in three patients. ConclusionsAP with decortication and autogenous BG is a good option for nonisthmal femoral shaft nonunions, such as supra-isthmal and infra-isthmal nonunions. In addition, this option is useful for selected cases of isthmal femoral shaft nonunions in which failure of exchange nailing is expected due to lack of a tight fit between the new larger nail and femoral cortices.

Subtrochanteric fracture non-unions with implant failure managed with the “Diamond” concept

BackgroundSubtrochanteric femoral non-unions in the setting of failed metalwork pose a challenging clinical problem. This study assessed the clinical outcome of patients treated according to the principles of the “Diamond” concept. MethodsBetween 2007 and 2011 all patients presented with a subtrochanteric atrophic aseptic non-union in the setting of metalwork failure (broken cephalomedullary reconstruction nail), and treated in a single tertiary referral unit were included to this study. The hypertrophic and the non-unions of pathologic fractures were excluded. The revision strategy was based on the “Diamond concept”; optimisation of the mechanical and the biological environment (implantation of growth factor (rhBMP-7), scaffold (RIA bone graft from contralateral femur) and concentrated mesenchymal stem cells (MSCs) harvested from the iliac crest). The minimum follow up was 26 months (16–48). ResultsFourteen patients met the inclusion criteria. A specific sequence of metalwork failure was noted with initial breakage of the distal locking screws followed by nail breakage at the lag screw level. The intraoperative examination of the removed nails revealed no gross structural damage indicative of inappropriate drilling at the time of the initial intramedullary nailing. Varus mal-alignment was present in the majority of the cases, with an average of 5.2 degrees (0–11). The average time to distal locking screw failure was 4.4 months (2–8.5) and nail failure was 6.5 months (4–10). The time to union after the revision surgery was 6.8 months (5–12). Complications included two deaths in elderly patients (due to unrelated causes), one pulmonary embolism, one myocardial infarction, one below the knee deep vein thrombosis and one blade plate failure that required further revision with double plating and grafting. ConclusionVarus mal-alignment must be avoided in the initial stabilisation of subtrochanteric fractures. Distal locking screw failure is predictive of future fracture non-union and nail breakage. In the absence of sepsis, a single stage procedure based on the “Diamond concept” that simultaneously optimizes the mechanical and biological environment is a successful method for managing complex subtrochanteric atrophic non-unions with failed metalwork.

Functional outcome following tibio-talar-calcaneal nailing for unstable osteoporotic ankle fractures

IntroductionFragility fractures of the ankle are increasing in incidence. Such fractures typically occur from low-energy injuries but lead to disproportionately high levels of morbidity. Ankle fractures in this age group are managed conservatively in plaster or by open reduction and internal fixation.Both modalities have shown high rates of failure in terms of delayed union or mal-union together with perioperative complications such as implant failure and wound breakdown. The optimal treatment of these patients remains controversial. ObjectivesWe aimed to review the functional outcome of patients with ankle fragility fractures primarily managed using a tibio-talar-calcaneal nail (TTC). MethodsWe retrospectively reviewed 31 consecutive patients primarily managed with a TCC nail for osteoporotic fragility fractures about the ankle. Data were collected via case notes, radiographic reviews and by clinical reviews at the outpatient clinic or a telephone follow-up. Information regarding patient characteristics, indication for operation, Arbeitsgemeinschaft für Osteosynthesefragen (AO) fracture classification, operative and postoperative complications, time to radiographic union and current clinical state including Olerud and Molander scores were recorded (as a measure of ankle function). ResultsNine of 31 patients had died by the time of follow-up. Mean preoperative and postoperative Olerud and Molander scores were 56 and 45, respectively. There were no postoperative wound complications. Twenty-nine of 31 patients returned to the same level of mobility as pre-injury. There were three peri-prosthetic fractures managed successfully with nail removal and replacement or plaster cast. There were two nail failures, both in patients who mobilised using only a stick, which were managed by nail removal.Ten of 31 patients were not followed up radiographically due to either infirmity or death. Thirteen of 21 followed up radiographically had evidence of union and 8/21 had none. None, however, had clinical evidence of fracture nonunion. ConclusionThe TTC nail can successfully be used to manage fragility fractures about the ankle in the elderly. Much like fractured neck of femur patients, who also have a high rate of mortality, this allows immediate mobilisation with minimal risk of wound complications. However, careful assessment must be made of each patient's mobility, as there is a significant incidence of device failure in the more active patient.

Inadequate three-point proximal fixation predicts failure of the gamma intramedullary nail

Inadequate three-point proximal fixation predicts failure of the gamma intramedullary nail

Dynamic responsive characteristics of nailed plywood–timber joints under harmonic vibrations

Dynamic tests of nailed plywood–timber joints are conducted under harmonic vibrations from 2 to 7 Hz. The principal results are as follows: under dynamic loading, nailed plywood–timber joints may break in low-cyclic bending fatigue failure of nails besides the other failure modes typical under static loading. The dynamic response of nailed plywood–timber joints is clearly dependent upon both the input frequency and the acceleration. These responsive characteristics arise from the nonlinear load–slip relationships and the characteristic cyclic stiffness degradation of nailed joints; that is, the cyclic degradation of the equivalent linear stiffness decreases the resonant frequencies of the same joints, which results in a transition of dynamic responses. It indicates that frequency components of seismic waves resonant to the frequencies corresponding to safety-limit stiffness of nailed joints may lead them to critical failures, even if the accelerations do not exceed the accelerations equivalent to the static damage-limit resistance.

Exploratory study on fatigue behaviour of laterally loaded, nailed timber joints, based on a dissipated energy criterion

Abstract Exploration of damage accumulation and reliable prediction of the fatigue lives of laterally loaded, nailed timber joints, are important to proper engineering design of wood structural systems subjected to earthquakes, cyclones/hurricanes or other loads causing fluctuating force flows in such joints. Failure of nailed timber joints typically involves the combination of yielding at plastic hinges in nail and/or the crushing of wood under nails. Force-based criteria can predict the static strength of such joints but cannot reliably predict fatigue behaviour because that depends on loading history and the dissipation of energy within plastic nail hinges and/or crushed wood. In this study, the failure modes, damage accumulation and fatigue life of nailed timber joints subjected to reversed cyclic loads under load-control condition were studied. The results showed that there are two failure modes of nailed timber joints, i.e., ductile failure of nails when the applied load level was higher than 85% of the static maximum load to failure (P max ) and brittle failure when the applied load level was &lt;85% of P max . The damage accumulation involved three phases, i.e., damage initiation, damage propagation and failure. Fatigue life of nailed joints under reversed cyclic loads was modelled by an energy criterion that separated dissipated energy into non-damaging and damaging components demarcated by the fatigue limit. This approach replicated the behaviour of nailed joints tested at 20 load levels of fully reversed repetitive cyclic loading.

Failure of intertrochanteric nailing due to distal nail jamming

Nail impingement against the anterior femoral cortex during nail insertion, or anterior cortex penetration, has been described in the literature as a worrying complication. We describe a previously unreported surgical failure due to a compromised dynamic distal locking caused by distal jamming of the nail. An 80-year-old male suffered a closed right intertrochanteric femoral fracture. Due to the presence of a long medial fragment, a 240 mm long titanium trochanteric nail was chosen to stabilize the fracture. Dynamic distal locking was performed by placing the distal screw at the inferior rim of the elliptical locking hole to allow compression of the fracture site during weight-bearing. Six-month X-ray follow-up revealed a broken nail and nonunion of the fracture due to failed dynamization of the distal locking screw. The nail was removed and replaced by a total arthroplasty. Due to the femoral anterior bow of the shaft, anterior cortical impingement of the distal tip of a nail may result in the failure of the nail to slide within the diaphyseal canal when using a medium-length nail preventing compression of the fracture. Dynamic distal locking can be ineffective if the ability of the distal nail to slide within the diaphyseal canal is hindered. This type of scenario can represent an opportunity for anterior nail impingement. Distal jamming of the nail can thus compromise dynamic compression at the fracture site during loading, thus inducing nonunion of the fracture, and leading to breakage of the osteosynthesis device. For these reasons, caution is recommended when using medium-length trochanteric nails for unstable trochanteric fractures.

Screw elastic intramedullary nail for the management of adult forearm fractures

Background:The failure of the conventional nailing of both forearm bones or isolated fractures of radius and ulna pose a potential problem of nail migration and rotational instability, despite the best reduction. The purpose of this paper is to evaluate the results of screw elastic intramedullary nail for the treatment of adult diaphyseal fractures of both forearm bones, which effectively addresses the problems associated with the conventional nailing systems for the forearm fractures.Materials and Methods:Seventy-six adults with forearm fractures (radius and ulna or isolated fracture of the single bone) were retrospectively evaluated. Fifty males and 26 females with the mean age of 38 years (range, 18-70 years) underwent closed reduction and screw intramedullary nail fixation. Ten patients required limited open reduction. The fractures were classified according to the AO/OTA system. The average followup was 12 months (range, 6 to 18 months).Results:The mean surgical time was 45 minutes (35 to 65 minutes). The meantime to union was 14 weeks (10-21 weeks). The results were graded as excellent in 50, good in 18 patients, and acceptable in eight patients, using the criteria of Grace and Eversman. We had superficial infection in three cases, one case of delayed infection, painful bursa in two cases, delayed union in two cases, malunion with dislocation of the DRUJ in two cases, injury to the extensor tendon of the thumb in one case, and one case of incomplete radioulnar synostosis.Conclusion:Closed reduction and internal fixation of forearm fractures by screw intramedullary nails reestablishes the near normal relationship of the fractured fragments. Screw intramedullary nail effectively controls both rotatory forces and the migration of the nail. It produces excellent clinical results in isolated fractures of either bones, as well as both bones of the forearm in adults.

Subtrochanteric fracture non-unions with implant failure managed with the diamond concept

Background The management of non-unions of subtrochanteric femoral fractures with associated implant failure is challenging. This study assessed the outcome of a cohort of patients treated according to the diamond concept. Methods Between 2005–2010 all patients with subtrochanteric aseptic non-unions presented post implant failure (Gamma Nail breakage) were eligible in the absence of severe systemic pathologies and comorbidities. Demographics, initial fracture pattern, method of stabilisation, mode of failure of metal work, time to revision of fixation, complications, time to union, and functional outcome were recorded over a minimum period of follow-up of 12 months. The revision strategy was based on the “diamond concept;” optimising the mechanical and biological environment (revision of fixation, osteoinduction/BMP-7, osteoconduction/RIA harvested graft, and osteogenicity/concentrate of bone marrow aspirate). Results Out of 280 nailing procedures 12 (4.3%) cases met the inclusion criteria. A consistent mode of metalwork failure was recorded with initial breakage of the proximal distal locking screw followed by nail breakage at the lag screw level. Biomechanical SEM analysis of the nails revealed no structural damage besides the standard fatigue striation. Varus mal-reduction was present in all cases, with an average of 7.3 degrees (5–11). The average time to screw failure was 4.3 months (2–6) and nail failure was 5.9 months (4–10). All but one of the cases were revised to a 95 degrees blade plate and one to an Affixus nail. Time to union was 6.5 months (5–10). All but one of the cases by 12 months have returned to their preinjury level of mobilisation. Conclusion Varus mal-reduction must be avoided in the initial stabilisation of subtrochanteric fractures. Proximal distal screw failure is predictive of future fracture non-union and subsequent nail breakage. The diamond concept for optimising mechanics and bone biology is a successful method for managing complex sub-trochanteric non-unions with failed metalwork.

Failure of intramedullary femoral nail with segmental breakage of distal locking bolts: a case report and review of the literature

Breakage of locking bolts is an important cause of interlocking nail failure in femoral fractures. It usually occurs in the form of single breakage in one of the distal bolts of the nail or nail breakage around the distal locking hole. Here we report an unusual case of intramedullary femoral nail failure with segmental breakage of both the distal locking bolts. Such a scenario usually complicates further management. We successfully managed this case with exchange nailing without bone grafting. Here we briefly reviewed the literature regarding such an unusual presentation and discussed in detail the possible etiology of such a presentation and the management options when facing such a complex situation.

Femoral reconstruction nail failures following fixation of extracapsular fractures of the hip—incidence, causes and prevention

Femoral reconstruction nail failures following fixation of extracapsular fractures of the hip—incidence, causes and prevention