Standardised cement augmentation of the PFNA using a perforated blade: A new technique and preliminary clinical results. A prospective multicentre trial

Finite element study on the micromechanics of cement-augmented proximal femoral nail anti-rotation (PFNA) for intertrochanteric fracture treatment

Blade cut-out is a common complication when using proximal femoral nail anti-rotation (PFNA) for the treatment of intertrochanteric fractures. Although cement augmentation has been introduced to overcome the cut-out effect, the micromechanics of this approach remain to be clarified. While previous studies have developed finite element (FE) models based on lab-prepared or cadaveric samples to study the cement-trabeculae interface, their demanding nature and inherent disadvantages limit their application. The aim of this study was to develop a novel 'one-step forming' method for creating a cement-trabeculae interface FE model to investigate its micromechanics in relation to PFNA with cement augmentation. A human femoral head was scanned using micro-computed tomography, and four volume of interest (VOI) trabeculae were segmented. The VOI trabeculae were enclosed within a box to represent the encapsulated region of bone cement using ANSYS software. Tetrahedral meshing was performed with Hypermesh software based on Boolean operation. Finally, four cement-trabeculae interface FE models comprising four interdigitated depths and five FE models comprising different volume fraction were established after element removal. The effects of friction contact, frictionless contact, and bond contact properties between the bone and cement were identified. The maximum micromotion and stress in the interdigitated and loading bones were quantified and compared between the pre- and post-augmentation situations. The differences in micromotion and stress with the three contact methods were minimal. Micromotion and stress decreased as the interdigitation depth increased. Stress in the proximal interdigitated bone showed a correlation with the bone volume fraction (R2 = 0.70); both micromotion (R2 = 0.61) and stress (R2 = 0.93) at the most proximal loading region exhibited a similar correlation tendency. When comparing the post- and pre-augmentation situations, micromotion reduction in the interdigitated bone was more effective than stress reduction, particularly near the cement border. The cementation resulted in a significant reduction in micromotion within the loading bone, while the decrease in stress was minimal. Noticeable gradients of displacement and stress reduction can be observed in models with lower bone volume fraction (BV/TV). In summary, cement augmentation is more effective at reducing micromotion rather than stress. Furthermore, the reinforcing impact of bone cement is particularly prominent in cases with a low BV/TV. The utilization of bone cement may contribute to the stabilization of trabecular bone and PFNA primarily by constraining micromotion and partially shielding stress.

Nail fixation of unstable trochanteric fractures with or without cement augmentation: A cost-utility analysis in the United States: Cost-utility of cement augmentation

OBJECTIVES

Recent clinical studies have shown favorable outcomes for cement augmentation for fixation of trochanteric fracture. We assessed the cost-utility of cement augmentation for fixation of closed unstable trochanteric fractures from the US payer's perspective.

METHODS

The cost-utility model comprised a decision tree to simulate clinical events over 1 year after the index fixation surgery, and a Markov model to extrapolate clinical events over patients' lifetime, using a cohort of 1,000 patients with demographic and clinical characteristics similar to that of a published randomized controlled trial (age ≥75 years, 83 % female). Model outputs were discounted costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) over a lifetime. Deterministic and probabilistic sensitivity analyses were performed to assess the impact of parameter uncertainty on results.

RESULTS

Fixation with augmentation reduced per-patient costs by $754.8 and had similar per-patient QALYs, compared to fixation without augmentation, resulting in an ICER of -$130,765/QALY. The ICER was most sensitive to the utility of revision surgery, mortality risk ratio after the second revision surgery, mortality risk ratio after successful index surgery, and mortality rate in the decision tree model. The probability that fixation with augmentation was cost-effective compared with no augmentation was 63.4 %, 58.2 %, and 56.4 %, given a maximum acceptable ceiling ratio of $50,000, $100,000, and $150,000 per QALY gained, respectively.

CONCLUSION

Fixation with cement augmentation was the dominant strategy, driven mainly by reduced costs. These results may support surgeons in evidence-based clinical decision making and may be informative for policy makers regarding coverage and reimbursement.

Augmented versus non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails for treating trochanteric fractures in patients over sixty-five years of age

PURPOSE

Intramedullary nailing is a common treatment for pertrochanteric fractures. However, implant-related mechanical failures, such as cut-out and cut-through, lead to higher rates of revision surgery, loss of autonomy, and mortality. Cemented augmentation enhances the bone-implant interface. This study compared the frequency of mechanical failures between augmented and non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails.

METHODS

This descriptive, retrospective study at a level 1 trauma centre included patients aged > 65 years with pertrochanteric fractures treated by a short augmented or non-augmented TFNA nail. The primary outcome was the comparison of cut-out or cut-through rates between groups at three and six months postoperatively.

RESULTS

Of the 181 patients analysed, 103 had augmented TFNA nails and 78 had non-augmented TFNA nails. There were no statistically significant differences between groups in terms of demographic characteristics, AO/OTA classification, or quality of reduction. The failure rate was significantly lower in the augmented group than in the non-augmented group: 1 (0.97%) versus 9 (11.54%) (p = 0.005). At six months postoperatively, there was no significant difference between the two groups concerning functional recovery, as measured by the Parker and EuroQoL 5-Dimensions scores.

CONCLUSIONS

For patients aged over 65 years, the use of the augmented TFNA nail may reduce the risk of fixation failures such as cut-out.

Outcomes of cement augmentation in fragility trochanteric hip fractures - A multicenter randomized controlled trial follow-up

PURPOSE

Cement augmentation is considered to improve the bone-implant construct stability in hip fragility fractures, additionally biomechanical studies show that cement augmentation improves the pull-out strength and increases resistance to failure. Thus far, the advantage of these technique used in a clinical scenario is yet to be determined METHODS: a randomized, multicenter, single-blinded clinical trial was conducted in patients aged 65 years or older who were admitted to two level I trauma centers with a fragility intertrochanteric hip fracture during September 2015 and December 2017. Patients were stratified into 2 groups: patients between 65 and 85 years and older than 85 years. A balanced block randomization was performed using blocks of 6 patients: 3 patients assigned to the control group (no augmentation) and 3 patients to the intervention group. Follow-up visits were done at 1, 3, 6 and 12 postoperative months documenting the tip-apex distance (TAD) as well as followed up after 5 to 7 years of surgical procedure documenting EQ5D, Parker Mobility Score and mortality rates at these different time points.

RESULTS

A total of 90 patients were included but only 53 patients completed a one-year follow up. The mean immediate postoperative and one-year follow up TAD measurement from the whole cohort (20.99 mm vs 21.3 mm, respectively) showed no statistical significance (P = 0.18). For patients in the control group, the difference of TAD measurements from the immediate postoperative and one-year follow-up was -0.25 mm (P = 0.441). For patients included in the intervention group, the difference of TAD measurement from the immediate postoperative and 1-year follow up was -0.48 mm (P = 0.383). No statistical difference was found when stratified by age (p = 0.78). One patient from the control group had an implant failure after 1-month postoperative. Readmission after 30 days showed no statistical difference between both groups (7 vs. 7 patients, p = 0.754). Augmentation did not show a difference in most of the functional outcomes nor quality of life after 5 to 7 years of surgical procedure.

CONCLUSIONS

The use of augmentation can be considered a safe procedure for the fixation of fragility hip fractures.

Failure of Fixation in Trochanteric Hip Fractures: Does Nail Design Matter?

OBJECTIVE

The objective of this study was to compare clinical outcomes of patients with trochanteric hip fractures treated with specific different cephalomedullary nail (CMN) designs.

METHODS

A scoping review of the English literature was performed. Inclusion criteria were studies comparing perioperative and postoperative outcomes of trochanteric hip fractures fixated by CMNs for one of the following CMN designs: short versus long nails, blade versus screw fixation, dual versus single lag screw fixation, and application of cement augmentation. Inclusion criteria consisted of human comparative clinical trials (randomized and observational). Exclusion criteria included noncomparative studies, studies comparing CMN with non-CMN devices or with arthroplasty, studies with less than 3 months follow-up, studies that did not provide relevant clinical outcome measures, biomechanical, finite element analyses, animal, or in vitro publications. Data regarding reoperations, peri-implant fractures, mechanical failure, nonunion, infection rates, and functional outcomes were reviewed.

RESULTS

Twenty-two studies met the inclusion criteria and formed the basis of this study. Failure of fixation rates and reoperation rates for each of the nail designs selected for evaluation is presented, in addition to specific outcome measures relevant to that nail design which was explored: peri-implant fracture-short versus long nails, and specific mechanism of failure-blade versus plate.

CONCLUSIONS

Decreased failure of fixation and reoperations rates were found for integrated dual lag screw fixation. Similar fixation failure and reoperation rates were found for the long versus short nails and for blade versus screw fixation.

LEVEL OF EVIDENCE

Diagnostic, Level IV.

Augmentation in fragility fractures, bone of contention: a systematic review

BACKGROUND

Osteoporosis is a complex multifactorial disease characterized by reduced bone mass and microarchitectural deterioration of bone tissue linked to an increase of fracture risk. Fragility fractures occur in osteoporotic subjects due to low-energy trauma. Osteoporotic patients are a challenge regarding the correct surgical planning, as it can include fixation augmentation techniques to reach a more stable anchorage of the implant, possibly lowering re-intervention rate and in-hospital stay.

METHODS

The PubMed database and the Google Scholar search engine were used to identify articles on all augmentation techniques and their association with fragility fractures until January 2022. In total, we selected 40 articles that included studies focusing on humerus, hip, spine, and tibia.

RESULTS

Literature review showed a quantity of materials that can be used for reconstruction of bone defects in fragility fractures in different anatomic locations, with good results over the stability and strength of the implant anchorage, when compared to non-augmented fractures.

CONCLUSION

Nowadays there are no recommendations and no consensus about the use of augmentation techniques in osteoporotic fractures. Our literature review points at implementing the use of bone augmentation techniques with a specific indication for elderly patients with comminuted fractures and poor bone quality.

Biomechanical analysis of recently released cephalomedullary nails for trochanteric femoral fracture fixation in a human cadaveric model

BACKGROUND

Recently, two novel concepts for intramedullary nailing of trochanteric fractures using a helical blade or interlocking dual screws have demonstrated advantages as compared to standard single-screw systems. However, these two concepts have not been subjected to a direct biomechanical comparison so far. The aims of this study were to investigate in a human cadaveric model with low bone quality (1) the biomechanical competence of nailing with the use of a helical blade versus interlocking screws, and (2) the effect of cement augmentation on the fixation strength of the helical blade.

METHODS

Twelve osteoporotic and osteopenic human cadaveric femoral pairs were assigned for pairwise implantation using either a short TFN-ADVANCED Proximal Femoral Nailing System (TFNA) with a helical blade head element or a short TRIGEN INTERTAN Intertrochanteric Antegrade Nail (InterTAN) with interlocking screws. Six osteoporotic femora, implanted with TFNA, were augmented with bone cement. Four groups were created: group 1 (TFNA) paired with group 2 (InterTAN), both consisting of osteopenic specimens, and group 3 (TFNA augmented) paired with group 4 (InterTAN), both consisting of osteoporotic specimens. An unstable trochanteric AO/OTA 31-A2.2 fracture was simulated and all specimens were tested until failure under progressively increasing cyclic loading.

RESULTS

Stiffness in group 3 was significantly higher versus group 4, p = 0.03. Varus (°) and femoral head rotation around the femoral neck axis (°) after 10,000 cycles were 1.9 ± 1.0/0.3 ± 0.2 in group 1, 2.2 ± 0.7/0.7 ± 0.4 in group 2, 1.5 ± 1.3/0.3 ± 0.2 in group 3 and 3.5 ± 2.8/0.9 ± 0.6 in group 4, being significantly different between groups 3 and 4, p = 0.04. Cycles to failure and failure load (N) at 5° varus or 10° femoral head rotation around the neck axis in groups 1-4 were 21,428 ± 6020/1571.4 ± 301.0, 20,611 ± 7453/1530.6 ± 372.7, 21,739 ± 4248/1587.0 ± 212.4 and 18,622 ± 6733/1431.1 ± 336.7, being significantly different between groups 3 and 4, p = 0.04.

CONCLUSIONS

Nailing of trochanteric femoral fractures with use of helical blades is comparable to interlocking dual screws fixation in femoral head fragments with low bone quality. Bone cement augmentation of helical blades provides significantly greater fixation strength compared to interlocking screws constructs.

Cost-Effectiveness of Cement Augmentation Versus No Augmentation for the Fixation of Unstable Trochanteric Fractures

BACKGROUND

A previous randomized controlled trial (RCT) demonstrated a trend toward a reduced risk of implant-related revision surgery following fixation with use of a Proximal Femoral Nail Antirotation (PFNA) with TRAUMACEM V+ Injectable Bone Cement augmentation versus no augmentation in patients with unstable trochanteric fractures. To determine whether this reduced risk may result in long-term cost savings, the present study assessed the cost-effectiveness of TRAUMACEM V+ cement augmentation versus no augmentation for the fixation of unstable trochanteric fractures from the German health-care payer's perspective.

METHODS

The cost-effectiveness model comprised 2 stages: a decision tree simulating clinical events, costs, and utilities during the first year after the index procedure and a Markov model extrapolating clinical events, costs, and utilities over the patient's lifetime. Sources of model parameters included the previous RCT, current literature, and administrative claims data. Outcome measures were incremental costs (in 2020 Euros), incremental quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). Model uncertainty was assessed with deterministic and probabilistic sensitivity analyses.

RESULTS

The base-case analysis showed that fixation with cement augmentation was the dominant strategy as it was associated with cost savings (€50.3/patient) and QALY gains (0.01 QALY/patient). Major influential parameters for the ICER were the utility of revision, rates of revision surgery within the first year after fixation surgery, and the costs of augmentation and revision surgery. Probabilistic sensitivity analyses demonstrated that estimates of cost savings were more robust than those of increased QALYs (66.4% versus 52.7% of the simulations). For a range of willingness-to-pay thresholds from €0 to €50,000, the probability of fixation with cement augmentation being cost-effective versus no augmentation remained above 50%.

CONCLUSIONS

Fixation with use of cement augmentation dominated fixation with no augmentation for unstable trochanteric fractures, resulting in cost savings and QALY gains. Given the input parameter uncertainties, future analyses are warranted when long-term costs and effectiveness data for cement augmentation are available.

LEVEL OF EVIDENCE

Economic and Decision Analysis Level II . See Instructions for Authors for a complete description of levels of evidence.

Indications for cement augmentation in fixation of geriatric intertrochanteric femur fractures: a systematic review of evidence

INTRODUCTION

Achieving durable mechanical stability in geriatric intertrochanteric proximal femur fractures remains a challenge. Concomitant poor bone quality, unstable fracture patterns, and suboptimal reduction are additional risk factors for early mechanical failure. Cement augmentation of the proximal locking screw or blade is one proposed method to augment implant anchorage. The purpose of this review is to describe the biomechanical and clinical evidence for cement augmentation of geriatric intertrochanteric fractures, and to elaborate indications for cement augmentation.

METHODS

The PubMed database was searched for English language studies up to January 2021. Studies that assessed effect of calcium phosphate or methylmethacrylate cement augmentation during open reduction and internal fixation of intertrochanteric fractures were included. Studies with sample size < 5, nontraumatic or periprosthetic fractures, and nonunion or revision surgery were excluded. Study selection adhered to PRISMA criteria.

RESULTS

801 studies were identified, of which 40 met study criteria. 9 studies assessed effect of cement augmentation on fracture displacement. All but one found that cement decreased fracture displacement. 10 studies assessed effect of cement augmentation on total load or cycles to failure. All but one demonstrated that augmented implants increased this variable. Complication rates of cement augmentation during ORIF of intertrochanteric fractures ranged from 0 to 47%, while non-augmented implants ranged from 0 to 51%. Reoperation rates ranged from 0 to 11% in the cement-augmented group and 0 to 11% in the non-augmented group. Fixation failure ranged from 0 to 11% in the cement-augmented group and 0 to 20% in the non-augmented group. Nonunion ranged from 0 to 3.6% in the cement-augmented group and 0 to 34% in the non-augmented group.

CONCLUSIONS

Calcium phosphate or PMMA-augmented CMN fixation of IT fractures increased construct stability and improved outcomes in biomechanical and early clinical studies. The findings of these studies suggest an important role for cement augmentation in patient populations at high risk of mechanical failure.

[Augmentation in the treatment of proximal humeral and femoral fractures]

BACKGROUND

Proximal humeral and trochanteric femoral fractures in older patients are typically caused by low-energy trauma and are therefore often associated with osteoporosis. The treatment of such fragility fractures can be difficult as implant purchase is reduced in osteoporotic bone. By augmenting the fixation with cement the contact surface between implant and bone can be increased, which improves the stability of the osteosynthesis.

OBJECTIVE

This article describes the operative technique for the augmentation of trochanteric femoral fractures treated with the Trochanteric Fixation Nail-Advanced (TFNA, DePuy Synthes, Oberdorf BL, Switzerland) and proximal humeral fractures stabilized with a PHILOS plate (DePuy Synthes). Furthermore, the evidence for the augmentation of these two fracture types is elucidated.

RESULTS

Biomechanical studies could show an improved stability of the osteosynthesis after successful augmentation for both fracture types. The current evidence also indicates a clinical reduction of fixation failure. Whether the augmentation has an influence on the functional result could so far not yet clearly be proven.

CONCLUSION

Augmentation seems to be a safe and valuable addition to available treatment options especially for patients with fragility fractures.

Cement distribution and initial fixability of trochanteric fixation nail advanced (TFNA) helical blades

INTRODUCTION

Early fixation and rehabilitation is the gold standard treatment for intertrochanteric femur fractures. To avoid postoperative complications such as cut-out or cut-through, cement augmentation with perforated helical blades has been developed. The purpose of this study was to evaluate the distribution of injected cement at the head-neck portion of proximal femur using computed tomography (CT) and to examine its initial fixability and clinical outcomes.

PATIENTS AND METHODS

Elderly patients who had intertrochanteric fractures were treated with a helical blade only (BO group) or with a helical blade and cement augmentation (CA group). After fracture reduction, trochanteric fixation nail advanced (TFNA) helical blades were inserted, aiming at the center/center position with 20 mm of tip-apex distance. In the CA group, 4.2 mL of cement was injected under an image intensifier (1.8 mL of cement was directed cranially and 0.8 mL each was directed to the caudally, anteriorly, and posteriorly). Patient demographics, radiographic parameters with CT, and post-operative clinical outcome were examined.

RESULTS

Each group included nine patients with similar demographics. Maximum penetration depth (MPD) in the CA group was significantly greater than those in the BO group for all four directions (p < 0.01). In the CA group, the anterior MPD was significantly greater than the posterior (p < 0.01) and the cranial (p = 0.02) MPD. Surface area and volume in the CA group were two-times and three-times larger than that in the BO group, respectively. Among radiographic parameters, ΔRotation angle in the CA group was significantly smaller than that of the BO group (p = 0.03). For the ΔParker score, the CA group showed less of a decrease than in the BO group (p < 0.01). Visual analog scale (VAS) for the passive range of motion (ROM) and for full-load walking in the CA group was significantly lower than those in the BO group (p < 0.01).

CONCLUSIONS

The initial fixability of the TFNA helical blade with cement augmentation demonstrated double the surface area and triple the volume. This suppressed implant micro-motion, reduced postoperative pain, and accelerated rehabilitation in the acute phase.

Use of a Trochanteric Fixation Nail-Advanced (TFNA) with cement augmentation for treatment of trochanteric fractures in patients greater than sixty five years of age

PURPOSE

Intramedullary nailing is the standard treatment of trochanteric fractures. Mechanical failure such as cut-out and cut-through are associated with high rates of revision surgery, functional impairment, and mortality. The aim of the study was to evaluate the rate of mechanical failure of the cement augmented screws of Trochanteric Fixation Nail-Advanced (TFNA) nails.

PATIENTS AND METHODS

A descriptive, retrospective, multi-operator, single-centre study was performed at our level 1 trauma centre between June 2019 and June 2020. Patients were included if they were > 65 years of age, presented with a trochanteric fracture treated with an augmented TFNA nail with 6 months of follow-up. The primary outcome was fixation failure rate (cut-out or cut-through) at three and six post-operative months. Secondary endpoints were intra-operative data, clinical scores, and radiographic analysis.

RESULTS

Forty-five patients (38 women and 7 men) were analysed. The mean age was 82.84 years (65-102, 9.50). There were no instances of mechanical failure in our series, after either three or six months of follow-up. No patient exhibited cut-out or cut-through. The mean amount of cement injected was 4.72 mL (3-6; 1.05). The mean length of surgery was 37.59 min (25-55; 6.48), and the mean intra-operative radiation exposure was 91.47 cGycm² (25.04-201.81; 51.40) for a mean duration of 43.11 s (17-86; 16.81). The mean duration of hospitalisation was 6.38 days (2-11; 2.27).

CONCLUSIONS

Our clinical results suggest that cement-augmented TFNA screws can be successfully used in the management of trochanteric fractures in patients > 65 years of age.

Mechanical testing of cephalomedullary nail lag screws after the addition of hydroxyapatite substitutes

OBJECTIVE

To compare the effects of 3 implant designs, with and without hydroxyapatite reinforcement, on push/pull-out strength and rotational torque.

METHODS

Three implant designs (Gamma 3, INTERTAN, and PFNA-II) were selected for comparison. A hydroxyapatite cylinder (NEOBRACE) was used to reinforce the interface between the femoral head and the lag screw. Maximum push-out strength, maximum pull-out strength, and peak rotational torque were measured in cellular blocks mimicking osteoporotic cancellous bone, with and without NEOBRACE.

RESULTS

In the push-out test, INTERTAN produced a significantly higher push-out strength in osteoporotic bone density cellular blocks than the other lag screws and blades (P < .05). With the addition of NEOBRACE, push-out strength was significantly higher for INTERTAN and PFNA-II (P < .05) than for the non-NEOBRACE group. In the pull-out test, INTERTAN produced a significantly higher pull-out strength in the osteoporotic bone density cellular blocks than did the other lag screws and blades (P < .05). With the addition of NEOBRACE, the pull-out strengths of INTERTAN and Gamma 3 versus those of the non-NEOBRACE group significantly increased (P < .05). In the rotational torque test, INTERTAN produced significantly greater rotational torque in the osteoporotic cellular blocks than the other lag screws and blades (P < .05). The addition of NEOBRACE resulted in a significant increase in rotational torque only for INTERTAN (P < .05).

CONCLUSION

The use of NEOBRACE supported an increase in push/pull-out strength and rotational torque, especially in systems with a relatively increased bone or implant interface area.Level of Evidence: Level V.

Recent advances in the local antibiotics delivery systems for management of osteomyelitis

Chronic osteomyelitis is a challenging disease due to its serious rates of mortality and morbidity while the currently available treatment strategies are suboptimal. In contrast to the adopted systemic treatment approaches after surgical debridement in chronic osteomyelitis, local drug delivery systems are receiving great attention in the recent decades. Local drug delivery systems using special carriers have the pros of enhancing the feasibility of penetration of antimicrobial agents to bone tissues, providing sustained release and localized concentrations of the antimicrobial agents in the infected area while avoiding the systemic side effects and toxicity. Most important, the incorporation of osteoinductive and osteoconductive materials in these systems assists bones proliferation and differentiation, hence the generation of new bone materials is enhanced. Some of these systems can also provide mechanical support for the long bones during the healing process. Most important, if the local systems are designed to be injectable to the affected site and biodegradable, they will reduce the level of invasion required for implantation and can win the patients’ compliance and reduce the healing period. They will also allow multiple injections during the course of therapy to guard against the side effect of the long-term systemic therapy. The current review presents different available approaches for delivering antimicrobial agents for the treatment of osteomyelitis focusing on the recent advances in researches for local delivery of antibiotics.

HIGHLIGHTS

Chronic osteomyelitis is a challenging disease due to its serious mortality and morbidity rates and limited effective treatment options.

Local drug delivery systems are receiving great attention in the recent decades.

Osteoinductive and osteoconductive materials in the local systems assists bones proliferation and differentiation

Local systems can be designed to provide mechanical support for the long bones during the healing process.

Designing the local system to be injectable to the affected site and biodegradable will reduces the level of invasion and win the patients’ compliance.

Effect of hydroxyapatite tubes on the lag screw intraoperative insertion torque for the treatment of intertrochanteric femoral fractures

BACKGROUND

Hydroxyapatite (HA) augments are frequently used in orthopedic surgery. However, the effectiveness of HA augments on the treatment of intertrochanteric femoral fractures remains unknown. This study aimed to investigate whether the use of HA tubes affects the intraoperative insertion torque of the lag screw during intertrochanteric femoral fracture surgery.

METHODS

From January 2016 to October 2020, 58 patients with intertrochanteric femoral fractures were included and divided into the HA treatment group (HA group, n = 29) and non-HA treatment group (N group, n = 29). Patients with intertrochanteric femoral fractures were treated using the Gamma3 nail system® with or without two HA tubes. HA tubes were inserted into the femoral head through the lag screw hole before the insertion of the lag screw. The mean and maximum intraoperative insertion torques of the lag screw, bone mineral density (BMD) of the uninjured opposite side femoral neck, and tip apex distance (TAD) of the lag screw on postoperative radiographs were assessed. To assess the loss of reduction after the surgery, we investigated the amounts of telescoping of the lag screw and the changes in the neck shaft angle.

RESULTS

The mean and maximum insertion torques were correlated with BMD in the HA and N groups, respectively. The mean and maximum insertion torques were not correlated with TAD in the HA and N groups, respectively. The mean torque/BMD ratio was significantly higher in the HA group than in the N group (p = 0.03). There were no significant differences in the maximum torque/BMD ratio between HA and N groups (p = 0.06), while the maximum torque/BMD ratio tended to be higher in the HA group than in the N group. The amounts of telescoping of the lag screw in the HA group were significantly lower than that in the N group (p = 0.04), while there were no significant differences in the changes in the neck shaft angle between two groups (p = 0.32).

CONCLUSION

Our results strongly suggest that the use of HA tubes increases the intraoperative lag screw insertion torque/BMD ratio and may improve the lag screw fixation by strengthening the bone/metal thread interface in the treatment of intertrochanteric femoral fractures.

Screw-Tip Augmented Locked Plating Versus Primary Reverse Total Shoulder Arthroplasty in Displaced Proximal Humeral Fractures: A Retrospective Comparative Cohort Study With a Mean Follow-Up of 39 Months

Introduction

This study compared the clinical and radiologic outcomes of screw-tip augmented locking plate osteosynthesis (STA) vs primary reverse total shoulder arthroplasty (RSA) in elderly patients with displaced proximal humeral fractures.

Methods

60 patients (age >65 years) with a displaced proximal humeral fracture underwent open reduction and internal fixation with locking plate and fluoroscopy controlled screw-tip augmentation. Sixty matched individuals (age, gender, fracture pattern, and mean follow-up) treated by RSA for fractures were identified from the institutional database and outcomes as well as occurring complications and need for revision surgery were compared.

Results

At 39 months’ follow-up, 25 patients in the STA group (mean age 74.5 ± 12 years, 76.7% woman) showed a mean Constant Score (CS) of 68 ± 18.8 points. Mean %CS compared to the contralateral side was 81.6 ± 19.8%. Of 60 matched individuals in the RSA group, 22 patients (mean age 78.9 ± 8.2 years, 76.7% woman) showed a mean CS of 60.6 ± 21.2 points (P = .33), and the mean %CS compared to the contralateral side was 81.6 (74.7 ± 18.6)% (P = .14). The overall complication rate in STA group was 32% (secondary varus or valgus displacement >10°, n = 4, avascular necrosis, n = 4). In RSA group, the overall complication rate was 4.5% (P = <.05). We observed one early onset infection. Revision surgery with removal of the prosthesis and PMMA spacer implantation for two-stage revision was necessary. The follow-up rate was 41.7 vs 36.7%.

Conclusions

Screw-tip augmented locked plating and reverse total shoulder arthroplasty result in comparable satisfying functional outcome 3 years following a displaced proximal humeral fracture in elderly patients. However, we noted a higher complication and revision rate in the STA group. In contrast, primary reversed shoulder arthroplasty resulted in a lower rate of complications and revisions, which may be beneficial in elderly patients.

Impact of Bone Cement Augmentation on the Fixation Strength of TFNA Blades and Screws

Background and Objectives: Hip fractures constitute the most debilitating complication of osteoporosis with steadily increasing incidences in the aging population. Their intramedullary nailing can be challenging because of poor anchorage in the osteoporotic femoral head. Cement augmentation of Proximal Femoral Nail Antirotation (PFNA) blades demonstrated promising results by enhancing cut-out resistance in proximal femoral fractures. The aim of this study was to assess the impact of augmentation on the fixation strength of TFN-ADVANCED^TM Proximal Femoral Nailing System (TFNA) blades and screws within the femoral head and compare its effect when they are implanted in centre or anteroposterior off-centre position. Materials and Methods: Eight groups were formed out of 96 polyurethane low-density foam specimens simulating isolated femoral heads with poor bone quality. The specimens in each group were implanted with either non-augmented or cement-augmented TFNA blades or screws in centre or anteroposterior off-centre positions, 7 mm anterior or posterior. Mechanical testing was performed under progressively increasing cyclic loading until failure, in setup simulating an unstable pertrochanteric fracture with a lack of posteromedial support and load sharing at the fracture gap. Varus-valgus and head rotation angles were monitored. A varus collapse of 5° or 10° head rotation was defined as a clinically relevant failure. Results: Failure load (N) for specimens with augmented TFNA head elements (screw/blade centre: 3799 ± 326/3228 ± 478; screw/blade off-centre: 2680 ± 182/2591 ± 244) was significantly higher compared with respective non-augmented specimens (screw/blade centre: 1593 ± 120/1489 ± 41; screw/blade off-centre: 515 ± 73/1018 ± 48), p < 0.001. For both non-augmented and augmented specimens failure load in the centre position was significantly higher compared with the respective off-centre positions, regardless of the head element type, p < 0.001. Augmented off-centre TFNA head elements had significantly higher failure load compared with non-augmented centrally placed implants, p < 0.001. Conclusions: Cement augmentation clearly enhances the fixation stability of TFNA blades and screws. Non-augmented blades outperformed screws in the anteroposterior off-centre position. Positioning of TFNA blades in the femoral head is more forgiving than TFNA screws in terms of failure load.

Cement augmentation of internal fixation for trochanteric fracture: a systematic review and meta-analysis

PURPOSE

This study aimed to determine the efficacy and safety of cement augmentation for internally fixed trochanteric fractures through a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

We searched the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov databases to identify RCTs, published until July 2020 that examined the effects of cement augmentation of internal fixation of trochanteric fractures. The primary outcomes were reoperation and Parker Mobility Score, whereas the secondary outcomes were 1-year mortality rate, EuroQol 5 Dimension, fixation failures, and adverse events. We conducted meta-analyses of the outcome measures using the random-effects models. We evaluated the certainty of evidence based on the Cochrane risk-of-bias tool and the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

We included three RCTs (326 participants). No significant effect was observed in favor of cement augmentation on all these outcomes. The certainty of evidence for fixation failures was very low and that for the other outcomes was low. The overall risk of bias for each outcome was high or of some concern in all included studies.

CONCLUSIONS

The effect of cement augmentation of internal fixation of trochanteric fractures was uncertain for the clinical outcomes due to the low certainty of evidence. Further RCTs with a low risk of selection bias may present convincing conclusions on the efficacy and safety of cement augmentation.

LEVEL OF EVIDENCE

Level 1.

Cementation: for better or worse? Interim results of a multi-centre cohort study using a fenestrated spiral blade cephalomedullary device for pertrochanteric fractures in the elderly

INTRODUCTION

Cephallomedullary nail fixation is currently the most popular treatment for pertrochanteric fractures. Despite continuous improvement in implant design, fixation failures still occur in a concerning number of cases. This study aims to evaluate the effect of cement augmentation of the new-generation Trochanteric Femoral Nail Advanced (TFNA) perforated spiral blade on complications including fixation failure in the elderly population.

MATERIALS AND METHODS

We retrospectively evaluated 107 patients aged 65 + treated for pertrochanteric fractures via TFNA between 2015 and 2019 based on whether cementation was used. Baseline demographics, fracture classifications, and reduction quality were compared. Patients with a follow-up of at least 6 months were analyzed for the primary outcome of fixation failure. All patients, regardless of loss to follow-up within 6 months, were analyzed for other complications including mortality.

RESULTS

Seventy-six patients (47 cemented, 29 non-cemented) had a minimum follow-up of 6 months (mean 13 months). There were no statistically significant differences between the two treatment groups in terms of patient demographics, ASA or AO/OTA fracture classification, reduction quality, or length of follow-up. There was a lower rate of fixation failure in the cement-augmented (CA) group versus the non-cement-augmented (NCA) group (2.1% vs 13.8%; p = 0.047). No cut-out or cut-through was observed in the CA group. Seven patients had adverse intraoperative events, with a significantly higher rate of fixation failure in these patients (40% vs 2.8%; p = 0.00). There were no statistically significant differences in 30-day mortality (6.3% CA vs 4.3% NCA; p = 0.632) or 3-month mortality (9.5% CA vs 12.8% NCA; p = 0.589).

CONCLUSIONS

Cementation of TFNA blades may decrease risk of fixation failure, however, the surgeon must be aware of potential complications such as cement leakage into the hip joint and be able to manage them as they arise.

Comparison of clinical outcomes with proximal femoral nail anti-rotation versus InterTAN nail for intertrochanteric femoral fractures: a meta-analysis

Background

A meta-analysis to access the pros and cons of proximal femoral nail anti-rotation (PFNA) versus InterTAN nail for intertrochanteric femoral fractures including available evidence extracted from literature.

Methods

According to the Cochrane systemic analysis method, randomized control trials (RCTs) and retrospective comparative observational studies which were related to the comparison of PFNA and InterTAN nail in the treatment of the elderly with intertrochanteric fractures were retrieved. Data were independently extracted from the included studies by two reviewers and analyzed using RevMan 5.3, and the quality of the studies was assessed.

Results

Two RCTs and seven observational studies were recruited, which consisted of 681 patients with PFNA and 651 patients with InterTAN nail. The meta-analyses showed no significant differences between the two approaches on Harris Hip Score, operation time, blood loss, time to union, mean hospital stay, union problems, intraoperative complications, hematoma, infection, and other complications in both RCTs and observational studies. In terms of other outcomes, for the RCTs, results showed that there were shorter tip–apex distance and reduced pain at thigh or hip in InterTAN nail than in PFNA; however, InterTAN nail was not superior to PFNA in cutout, reoperation, and femoral shaft fracture; for observational studies, the risk of the screw migration (RR = 5.13, 95%CI [1.33,19.75], P = 0.02), cutout (RR = 3.26, 95%CI [1.64,6.47], P = 0.0008), the varus collapse of the femoral head (RR = 7.19, 95%CI [2.18,23.76], P = 0.001), femoral shaft fracture (RR = 5.73, 95%CI [2.24,14.65], P = 0.0003) treated by InterTAN nail were significantly decreased, compared with those by PFNA; however, no significant differences were observed in the aspects of tip–apex distance and pain at thigh or hip between these two groups.

Conclusion

Analysis of a large number of relevant clinical indicators available shows that InterTAN nail has better clinical manifestation than PFNA in treating unstable femoral intertrochanteric fractures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02031-8.

Cement augmentation for trochanteric fracture in elderly: A systematic review

BACKGROUND

Cement augmentation of internal fixation of hip fracture has reported to improve fracture stability in osteoporotic hip fractures, reducing the risk of cut-out of the sliding screw through the femoral head. The purpose of present study was to perform a systematic literature review on the effects of augmentation technique in patients with osteoporotic hip fractures.

MATERIAL AND METHODS

A comprehensive literature search was systematically performed to evaluate all papers published in English language included in the literature between January 2010 and July 2020, according to the PRISMA 2009 guidelines. In vivo and in vitro studies, case reports, review articles, cadaveric studies, biomechanical studies, histological studies, oncological studies, technical notes, studies dealing with radiological classifications and studies on revision surgery were excluded.

RESULTS

A total of 5 studies involving 301 patients were included. Patients had a mean age of 84.6 years and were followed up for a mean period of 11 months. The proximal femoral fractures were stabilized with implantation of the PFNA or Gamma nail and augmentation was performed with two different cements: polymethylmethacrylate (PMMA) in 4 studies and calcium phosphate (CP) in one study. Overall, 57.5% of patients reached the same or greater preoperative mobility, and postoperative Parker Mobility Score and Harris Hip Score were acceptable. No significantly complications were observed, and no additional surgery related to the implant was required.

CONCLUSION

The results of this systematic review show that cement augmentation is a safe and effectiveness method of fixation to treat trochanteric fractures.

Early Experience with the Trochanteric Fixation Nail-Advanced (TFN-A): A Descriptive Review of Thirty-Four Cases from a Single Center

BACKGROUND

The Trochanteric Fixation Nail-Advanced (TFN-A) is offered as a "next-generation" solution to the ever-increasing incidence of pertrochanteric and intertrochanteric fractures. It aims to build upon the success of earlier-generation proximal femur implants, while at the same time attempting to address complications, like varus collapse, cut-out, implant failure and anterior cortical perforation/impingement. It also aims to provide the surgeon with flexibility by offering varied options under a single implant system.

OBJECTIVES

This descriptive study looked at the early outcomes of the TFN-A as used in a single trauma centre. It attempts to shed light on the question of whether the TFN-A is at least equivalent to more established proximal femur implants in terms of fixation while reducing complication rates.

METHODS

Thirty-four patients who underwent fixation using the TFN-A at a single centre from October 2016 to July 2018 were retrospectively reviewed for this study. All surgeries were done by experienced orthopaedic surgeons. The decision for cement augmentation of the femoral head element was made on a case-to-case basis. Radiographs of the hip, pelvis and femora were taken to monitor fracture healing and evaluate post-fixation neck-shaft angle (NSA)/varus collapse, cut-out/cut-through, implant failure and anterior cortical impingement/perforation.

RESULTS

All thirty-four patients had neck-shaft angles within 5 degrees of the contralateral hip immediately post-surgery. Two patients had varus collapse > 5 degrees on follow-up but did not progress to cut-out. Two patients had broken distal locking screws, albeit their fractures healed uneventfully. There were four cases of cement augmentation with "retrograde filling", wherein most of the cement went into the femoral neck. No patients experienced distal anterior cortical impingement or perforation. All but one patient subsequently progressed to full weight-bearing.

CONCLUSION

Early experience with the TFN-A appears to suggest that it is at least comparable to preceding proximal femur nail devices in terms of fixation. Absence of anterior cortical impingement or perforation suggests that the TFN-A shows promise in addressing this issue. The incidence of "retrograde cement filling" is a previously unreported point of interest for head-neck element augmentation which requires further study.

Trochanteric fixation nail advanced with helical blade and cement augmentation: early experience with a retrospective cohort

Intra-articular screw cut-out is a potential complication of intertrochanteric femur fracture fixation with a cephalomedullary nail. Cement augmentation of fixation in the proximal segment offers the prospect of increased stability and fewer complications, but clinical experience with non-resorbable cement is limited. To determine the handling properties and efficacy of this new technique, we performed a retrospective propensity-matched cohort of forty-four geriatric intertrochanteric femur fractures treated with a cephalomedullary nail with (n = 11) or without (n = 33) augmentation with non-resorbable cement injected into the proximal segment. In the patients treated with cement augmentation, at minimum 3-month follow-up, there were no instances of intra-articular cut-out, and no increase in re-operation compared to conventional fixation. Cement augmentation appears to be safe and effective in geriatric intertrochanteric femur fractures to mitigate risk of cut-out.

A novel method for intraoperative osseomechanical strength measurements: a biomechanical ex vivo evaluation on proximal femora

INTRODUCTION

The increasing number of geriatric traumatology cases has intensified the need to reliably and objectively evaluate local bone quality, the latter poses a decisive factor for the choice of an optimal approach to treat osteoporotic fractures. Osteodensitometry imaging techniques are not routinely available in acute operative settings, nor do they provide objective information on local bone properties specifically needed for the prognosis of implant stability.

MATERIALS AND METHODS

This study sought to verify ex vivo the feasibility and sensitivity of a novel method for the determination of local bone strength in the acute operative setting (intraoperative osseomechanical strength measurement; IOSM) that is based on the principle of material displacement resistance against the force of a rotary indenter. Samples consisted of human femoral heads obtained after total hip replacement. Comparisons were made with results obtained via conventional dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (qCT).

RESULTS

Regression analyses of the results showed a highly significant correlation between the IOSM and the control methods (r = 0.61 and r = 0.56; p < 0.01), indicating that this new approach qualifies as a reliable tool for the intraoperative evaluation of the intrinsic local bone strength.

CONCLUSIONS

The intraoperative integration of this method may support surgeon on taking proper decisions in terms of optimal surgical approaches and prevention of complications inherent to osteoporotic bone.

Predicting Factors for Return to Prefracture Ambulatory Level in High Surgical Risk Elderly Patients Sustained Intertrochanteric Fracture and Treated With Proximal Femoral Nail Antirotation (PFNA) With and Without Cement Augmentation

Introduction:

Postoperative outcomes in the elderly patients with intertrochanteric fracture were generally poor with a low rate of return to prefracture ambulatory level (RPAL). Recent studies showed that proximal femoral nail antirotation (PFNA) with cement augmentation might be useful for postoperative functional recovery. This study aimed to compare the outcomes in elderly patients with high surgical risk, American Society of Anesthesiologist (ASA) grade 3 or 4, who sustained intertrochanteric fractures and were treated with PFNA with and without cement augmentation, and to correlate perioperative surgical factors with the RPAL.

Methods:

A retrospective consecutive series was conducted based on 135 patients with prefracture ambulation classified as independent in community with or without a single cane (68 in augmented group and 67 in control group). Perioperative data and data on the complications within 1-year postsurgery were collected and compared. Predictive factors for RPAL were analyzed via logistic regression analysis.

Results:

The overall 1-year postoperative mortality rate was 10% (n = 14) with no significant difference between groups (P = .273). The proportion of elderly patients with RPAL in the augmented group was significantly higher than for those in the control group (48% vs 29%, P = .043). Via univariate analysis, ASA grade 4 (P = .077), history of stroke (P = .035), and use of cement augmentation (P = .041) were correlated with RPAL. However, multivariate regression analysis showed that ASA grade 4 (odds ratio [OR] = 0.40, 95% confidence interval [CI]: 0.18-0.90, P = .026) and use of cement augmentation (OR = 2.72, 95% CI: 1.22-6.05, P = .014) were the significant predictors for RPAL.

Discussion and Conclusions:

The results of the present study showed that PFNA with cement augmentation is safe and effectiveness in the intertrochanteric fracture treatment of elderly. Postoperative functional recovery, like RPAL, in elderly patients who sustained intertrochanteric fractures is relatively low, especially in those with ASA grade 4. However, cement augmentation with PFNA might be helpful for increasing the RPAL in high-surgical-risk geriatric patients.

Intraoperative assessment of reduction quality during nail fixation of intertrochanteric fractures

BACKGROUND

The quality of intertrochanteric fracture reduction has traditionally been evaluated using simple radiographs. However, subjective intraoperative evaluation and efforts to achieve a perfect reduction are essential for optimal outcomes. This study aimed to establish criteria for the intraoperative assessment of the quality of intertrochanteric fracture reduction and also analyzed postoperative outcomes in terms of reduction quality.

METHODS

This study included 106 patients who received cephalo-medullary nailing for the treatment of intertrochanteric fractures between March 2012 and May 2016 and were followed-up for at least 1 year. An image intensifier was used intraoperatively to evaluate reduction quality by examining the restoration of anteromedial cortex continuity, and neck-shaft angle and anteversion. Based on the reduction quality, the patients were classified into optimal, acceptable, and unacceptable groups, with intervention provided for the unacceptable group. The need for revision surgery and the degree of blade sliding were assessed, and postoperative outcomes related to implant position were analyzed.

RESULTS

Over 50% of patients with Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type 31A2 and A3 fractures were assigned to the unacceptable group after closed reduction (P = 0.006), and 60 cases required additional reduction. Approximately 40% of cases classified as clinically unacceptable required revision, and the rate of sliding was ≥2-fold higher in the unacceptable group than those in the optimal and acceptable groups (P = 0.015), with an average excessive sliding of 9.85 mm. Regarding implant position, cut-out or penetration were observed in cases with superiorly-located blades (P = 0.039).

CONCLUSIONS

Good outcomes cannot be achieved with traction alone for femoral intertrochanteric fractures. Active management is required because accurate anteromedial cortex reduction, and restoration of neck-shaft angle and anteversion are essential in femoral intertrochanteric fractures.

Assessment of two augmentation techniques on the mechanical properties of titanium cannulated bone screws

OBJECTIVE

To determine the effects of 2 augmentation techniques on the mechanical properties of titanium cannulated bone screws.

SAMPLE

33 titanium cannulated bone screws (outer diameter, 6.5 mm; guide channel diameter, 3.6 mm).

PROCEDURES

11 screws were allocated to each of 3 groups. The guide channel of each screw was filled with polymethyl methacrylate bone cement alone (OCS group) or in combination with a 3.2-mm-diameter orthopedic pin (PCS group) or remained unmodified (control group) before mechanical testing. Each screw underwent a single-cycle 3-point bending test to failure with a monotonic loading rate of 2.5 mm/min. Failure was defined as an acute decrease in resistance to load of ≥ 20% or a bending deformation of 15 mm. Mechanical properties were determined for each screw and compared among the 3 groups.

RESULTS

All screws in the control and OCS groups and 1 screw in the PCS group broke during testing; a 15-mm bending deformation was achieved for the remaining 10 screws in the PCS group. Maximum load and load at failure differed significantly among the 3 groups. Stiffness and load at yield for the PCS group were significantly greater than those for the control and OCS groups but did not differ between the control and OCS groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of bone cement and an orthopedic pin to fill the guide channel of cannulated screws significantly increased the strength of the construct, but ex vivo and in vivo studies are necessary before this augmentation technique can be recommended for clinical patients.

Augmented Fixation for Fractures of the Appendicular Skeleton

Despite advances in technology such as locked plating, osteoporotic bone and bone defects remain challenging complications for orthopaedic surgeons. The concept of augmented fixation is useful in these settings. Augmented fixation can be described as improving construct strength and stability by enhancing the surrounding environment. By understanding and using the techniques of alternative fixation strategies, endosteal or medullary support, structural grafting, or the use of bone graft substitutes in combination with standard or integrated fixation, surgeons can improve the chances of success when treating difficult fractures. The purpose of this article is to introduce the reader to the concept of augmented fixation, review strategies for its application, and review applicable published results.

Femoral offset loss and internal arch restoration defect are correlated with intramedullary nail cut-out complications after pertrochanteric fractures: a case-control study

BACKGROUND AND PURPOSE

In a previous study, we investigated the link between the femoral offset (FO) loss by trochanteric impaction (TI) and cut-out complication occurrence after pertrochanteric fractures. Three major factors are likely to drive to failure after intramedullary nailing (IN): fracture stability, reduction quality and osteosynthesis quality. We wanted to investigate the quality of the fracture reduction through the TI and the neck-shaft angle (NSA) measurement and correlate these parameters with the risk of mechanical failure occurrence.

MATERIALS AND METHODS

It was a retrospective multicentric one case-one control match design study with age and gender randomization. The cases presented a mechanical failure of nailing: [Formula: see text] in percentage. Femoral rotation was taken into account, and all TI were rotation-corrected (TI_corrected). Rotation-corrected neck-shaft angles (NSA_corrected) were calculated. The neck-shaft angle gap between the fractured and the healthy sides (NSA_gap) was a ratio: [Formula: see text] in percentage. The tip-apex distance (TAD) was measured. Absolute values of TI_corrected and NSA_gap were analyzed.

RESULTS

Twenty-one cases and 21 controls were examined. The average TI_corrected rate was 30% for the cases and 11% for the controls (p = 0.007). A 13% TI_corrected threshold had maximum specificity and sensitivity, equal to 71%. The average TAD was 27 mm for cases and 19 mm for controls (p = 0.004). The average NSA_gap rate was 7% for the case group and 4% for the control group (p = 0.009). The areas under the ROC curves for TI_corrected, TAD and NSA_gap were 0.73, 0.73 and 0.66, respectively.

INTERPRETATION

Closed reduction and exclusive implantation of IN do not seem optimal in case of FO or NSA restoration failure after pertrochanteric fractures.

LEVEL OF EVIDENCE

Level III, case-control study.

Migration of the Lag Screw after Intramedullary Treatment of AO/OTA 31.A2.1-3 Pertrochanteric Fractures Does Not Result in Higher Incidence of Cut-Outs, Regardless of Which Implant Was Used: A Comparison of Gamma Nail with and without U-Blade (RC) Lag Screw and Proximal Femur Nail Antirotation (PFNA)

The best intramedullary nail for the treatment of unstable AO/OTA 31.A2.1-3 fractures remains uncertain. A total of 237 patients (45 male, 192 female) were eligible for the assessment with an average age of 81.9 ± 10.5 years and a minimum follow-up of six months. We assessed the cut-out rate, the TAD and calTAD (Tip Apex distance) of three different implants. An overall cut-out rate of 2.5% (n = 6) was observed. The cut-out rate was 1.2% (n = 1) in the Proximal Femur Nail Antirotation (PFNA) group, 3.7% (n = 3) in the Gamma Nail group and 2.9% (n = 2) in the Gamma3^® with a U-Blade (RC) lag-screw group. The TAD and calTAD differed between the cut-out and non-cut group-20.0 mm vs. 18.5 mm and 13.1 mm vs. 15.3 mm, respectively. A significantly higher TAD of 32.5 mm could be seen in the cut-out after PFNA (p < 0.0001). The only significant change in follow-up using Parker's ratio was observed in the PFNA group (p < 0.0001). The rate of patients requiring surgery after complications was 8.4% (n = 20) without any significant difference between the three groups. The PFNA blade showed significant migration within the femoral head, however the cut-out rate remained the smallest compared to Gamma3 with or without additional U-Blade (RC) lag screw.

Cement augmentation of the Proximal Femoral Nail Antirotation (PFNA) - A multicentre randomized controlled trial

INTRODUCTION

New implant designs like the Proximal Femoral Nail Antirotation (PFNA) were developed to reduce failure rates in unstable pertrochanteric fractures in the elderly. Standardized implant augmentation with up to 6 mL of polymethylmethacrylate (PMMA) cement has been introduced to enhance implant anchorage by increasing the implant-bone interface in osteoporotic bone conditions. Biomechanically, loads to failure were significantly higher with augmentation. The primary objective of this study was to compare the mobility of patients with closed unstable trochanteric fractures treated by PFNA either with or without cement augmentation.

PATIENTS AND METHODS

A prospective multicentre, randomized, patient-blinded trial was conducted with ambulatory patients aged 75 or older who sustained a closed, unstable trochanteric fracture. Surgical fixation had to be performed within 72 h after admission. Outcomes were evaluated at baseline, during surgery, 3 to 14 days after surgery, 3 months, 6 months, and 12 months after surgery. To evaluate the primary objective, patients' walking speed was assessed by the Timed Up and Go (TUG) test. Secondary objectives included the analysis of implant migration assessed on radiographs, quality of life measured by the Barthel Index, mobility measured by the Parker Mobility Score, and complications.

RESULTS

Of 253 randomized patients, 223 patients were eligible: 105 patients were allocated to the PFNA Augmentation group and 118 to PFNA group. At 3 to 14 days after surgery, there was no statistical significant difference in mean walking speed between the treatment groups. For the secondary objectives, also no statistical significant differences were found. However, no patient in the PFNA Augmentation group had a reoperation due to mechanical failure or symptomatic implant migration compared to 6 patients in the PFNA group.

CONCLUSIONS

Augmentation of the PFNA blade did not improve patients' walking ability compared to the use of a non-augmented PFNA but might have the potential to prevent reoperations by strengthening the osteosynthesis construct.

[Traumatology in the elderly : Multimodal prevention of delirium and use of augmentation techniques]

Recent data show that 20-80% of surgery patients are affected by delirium during inpatient clinical treatment. The medical consequences are often dramatic and include a 20 times higher mortality and treatment expenses of the medical unit increase considerably. At the University Hospital of Münster a multimodal and interdisciplinary concept for prevention and management of delirium was developed: all patients older than 65 years admitted for surgery are screened by a specialized team for the risk of developing delirium and treated by members of the team if there is a risk of delirium. Studies proved that by this multimodal approach the incidence of delirium was lowered and therefore the quality of medical care improved.When surgical treatment of fractures in the elderly is required, limited bone quality as well as pre-existing implants can complicate the procedure. Secondary loss of reduction after osteosynthesis and avulsion of the implant in particular must be prevented. Augmentation of the osteosynthetic implant with bone cement can increase the bone-implant interface and therefore stability can be improved. Additional intraoperative 3D imaging can be necessary depending on the localization of the fracture. In biomechanical studies we could prove greater stability in the osteosynthesis of osteoporotic fractures of the distal femur when using additional bone cement; therefore, the use of bone cement is an important tool, which helps to prevent complications in the surgical treatment of fractures in the elderly. Nevertheless, special implants and technical skills are required and some safety aspects should be considered.

Decision Making in the Management of Extracapsular Fractures of the Proximal Femur - is the Dynamic Hip Screw the Prevailing Gold Standard?

Currently, approximately half of all hip fractures are extracapsular, with an incidence as high as 50 in 100,000 in some countries. The common classification systems fail to explain the logistics of fracture classification and whether they all behave in the same manner. The Muller AO classification system is a useful platform to delineate stable and unstable fractures. The Dynamic hip screw (DHS) however, has remained the 'gold standard' implant of choice for application in all extracapsular fractures. The DHS relies on the integrity and strength of the lateral femoral wall as well as the postero-medial fragment. An analysis of several studies indicates significant improvements in design and techniques to ensure a better outcome with intramedullary nails. This article reviews the historical trends that helped to evolve the DHS implant as well as discussing if the surgeon should remain content with this implant. We suggest that the gold standard surgical management of extracapsular fractures can, and should, evolve.

The role of lesser trochanter fragment in unstable pertrochanteric A2 proximal femur fractures - is refixation of the lesser trochanter worth the effort?

BACKGROUND

Instability of osteoporotic pertrochanteric fractures is defined by loss of medial/lateral cortical integrity with the posteromedial fragment including the lesser trochanter being pivotal for load distribution. Literature addressing the importance of lesser trochanter refixation is scarce. To clarify the effect of lesser trochanter refixation on primary stability in these fractures, following study was performed.

METHODS

21 femora were match-paired in 3 groups and osteotomized, creating pertrochanteric fractures (AO-31A2). Group 1 was stabilized with a proximal femoral nail, group 2 with a dynamic hip screw and group 3 with an augmented proximal femoral nail. Each femur was tested non-destructively at 200 and 400N with and without refixation of the lesser trochanter (configuration A/B). The overall stiffness and movement of the femoral neck was recorded.

FINDINGS

At 200N, refixation reduced movement of the femoral neck and increased overall stiffness significantly in group 1 and 3. At 400N, refixation decreased movement of the femoral neck not significantly in all groups (1=38%, 2=36%, 3=43%). The augmented proximal femoral nail after refixation showed the highest stability of all constructs.

INTERPRETATION

Refixation of the lesser trochanter may increase the primary stability of pertrochanteric fracture osteosynthesis as all groups showed a higher primary stability. Therefore, refixation should be considered in unstable, osteoporotic fractures. If additional trauma through refixation appears inappropriate, cement augmentation should be performed as it showed only 9% less stability than a non-augmented proximal femoral nail with refixation of the lesser trochanter.

[Augmentation techniques on the proximal femur]

BACKGROUND

Due to the demographic change fractures of the proximal femur are an increasing major healthcare problem and are associated with the highest mortality among frailty fractures.

OBJECTIVES

These mainly osteoporosis-associated fractures of the hip often represent a surgical challenge and the outcome has a decisive influence on the preservation of function and independency of orthogeriatric patients. Augmentation techniques could improve the stability of osteosynthesis in proximal femoral fractures.

METHODS

Cement augmentation of proximal femoral nailing (PFNA) for the treatment of pertrochanteric femoral fractures is the most commonly used and standardized method of augmentation for these fractures by which a safer condition for immediate full weight bearing and mobilization can be achieved.

RESULTS

In biomechanical and clinical studies good fracture healing was shown and there was no evidence of cement-associated complications in augmented PFNA nailing. In the majority of patients the mobility level prior to trauma could be achieved.

CONCLUSION

In addition to the optimal surgical treatment, secondary prevention such as osteoporosis management to avoid further fractures is crucial in the treatment of these patients. This article is based on the current literature and provides an overview of the possible applications of cement augmentation for the treatment of proximal femoral fractures. In addition the surgical approach as well as previous scientific data on an established osteosynthesis using cement-augmented PFNA for the treatment of pertrochanteric frailty fractures are presented.

[Augmentation technique on the proximal humerus]

BACKGROUND AND OBJECTIVES

The treatment of osteoporotic fractures is still a challenge. The advantages of augmentation with respect to primary in vitro stability and the clinical use for the proximal humerus are presented in this article.

MATERIAL AND METHODS

In this study six paired human humeri were randomized into an augmented and a non-augmented group. Osteosynthesis was performed with a PHILOS plate (Synthes®). In the augmented group the two screws finding purchase in the weakest cancellous bone were augmented. The specimens were tested in a 3-part fracture model in a varus bending test.

RESULTS

The augmented PHILOS plates withstood significantly more load cycles until failure. The correlation to bone mineral density (BMD) showed that augmentation could partially compensate for low BMD.

CONCLUSION

The augmentation of the screws in locked plating in a proximal humerus fracture model is effective in improving the primary stability in a cyclic varus bending test. The targeted augmentation of two particular screws in a region of low bone quality within the humeral head was almost as effective as four screws with twice the amount of bone cement. Screw augmentation combined with a knowledge of the local bone quality could be more effective in enhancing the primary stability of a proximal humerus locking plate because the effect of augmentation can be exploited more effectively limiting it to the degree required. The technique of augmentation is simple and can be applied in open and minimally invasive procedures. When the correct procedure is used, complications (cement leakage into the joint) can be avoided.

Impact of cement-augmented condylar screws in locking plate osteosynthesis for distal femoral fractures - A biomechanical analysis

INTRODUCTION

Compromised bone quality and the need for early mobilization continue to lead to implant failure in elderly patients with distal femoral fractures. The cement augmentation of screws might facilitate improving implant anchorage. The aim of this study was to analyse the impact of cement augmentation of the condylar screws on implant fixation in a human cadaveric bone model.

MATERIAL AND METHODS

Ten pairs of osteoporotic femora (mean age: 90 years, range: 84-99 years) were used. A 2-cm gap osteotomy was created in the metaphyseal region to simulate an unstable AO/OTA 33-A3 fracture. All specimens were treated with a polyaxial locking plate. Specimens randomly assigned to the augmented group received an additional cement augmentation of the condylar screws using bone cement. A servohydraulic testing machine was used to perform incremental cyclic axial loading using a load-to-failure mode.

RESULTS

All specimens survived at least 800N of axial compressive force. The mean compressive forces leading to failure were 1620N (95% CI: 1382-1858N) in the non-augmented group and 2420N (95% CI: 2054-2786N) in the group with cement-augmented condylar screws (p=0.005). Deformation with cutting out of the condylar screws and condylar fracture were the most common reasons for failure in both groups. Whereas axial stiffness was comparable between both osteosyntheses (p=0.508), significant differences were observed for the plastic deformation of the constructs (p=0.014).

CONCLUSION

The results of the present study showed that the cement augmentation of the condylar screws might be a promising technique for the fixation of distal femoral fractures in elderly patients with osteoporotic bones.

[Pertrochanteric femoral fractures in the elderly]

Pertrochanteric fractures are one of the most common injuries in the elderly and due to the demographic changes the incidence and importance of this fracture entity will even increase in the future. The dynamic hip screw (DHS) has been used as the gold standard implant in the treatment of pertrochanteric femoral fractures for many years but recent studies have shown that cephalomedullary nails have some advantages. Due to the high incidence, operative treatment of these fractures is part of the standard repertoire of trauma surgeons and this article therefore provides an overview of existing knowledge and new trends in the treatment of pertrochanteric femoral fractures.

The use of augmentation techniques in osteoporotic fracture fixation

There are an increasing number of fragility fractures, which present a surgical challenge given the reduced bone quality of underlying osteoporosis. Particularly in aged patients, there is a need for early weight bearing and mobilization to avoid further complications such as loss of function or autonomy. As an attempt to improve fracture stability and ultimate healing, the use of biomaterials for augmentation of osseous voids and fracture fixation is a promising treatment option. Augmentation techniques can be applied in various locations, and fractures of the metaphyseal regions such as proximal humerus, femur, tibia and the distal radius remain the most common areas for its use. The current review, based on the available mechanical and biological data, provides an overview of the relevant treatment options and different composites used for augmentation of osteoporotic fractures.

Periprosthetic fracture fixation in osteoporotic bone

Fixation techniques of periprosthetic fractures are far from ideal although the number of this entity is rising. The presence of an intramedullary implant generates its own fracture characteristics since stiffness is altered along the bone shaft and certain implant combinations affect load resistance of the bone. Influencing factors are cement fixation of the implant, intramedullary locking and extramedullary or intramedullary localization of the implant and the cortical thickness of the surrounding bone. Cerclage wires are ideally suited to fix radially displaced fragments around an intramedullary implant but they are susceptible to axial and torsional load. Screws should be added if these forces have to be neutralized. Stability of the screw fixation itself can be enhanced by embracement configuration around the intramedullary implant. Poor bone stock quality, often being present in metaphyseal areas limits screw fixation. Cement augmentation is an attractive option in this field to enhance screw purchase.

Which factor is most important for occurrence of cutout complications in patients treated with proximal femoral nail antirotation? Retrospective analysis of 298 patients

INTRODUCTION

Mechanical complications, such as cut-out of the head-neck fixation device, are the most common causes of morbidity after trochanteric femur fracture treatment. The causes of cut-out complications are well defined in patients who are treated with sliding hip screws and biaxial cephalomedullary nails but there are few reports about the patients who are treated with proximal femoral nail antirotation.

AIM

The purpose of this study was to evaluate the most important factor about occurance of cutout complication and also to evaluate the risks of the combination of each possible factors.

PATIENTS AND METHODS

Overally 298 patients were enrolled in the study. Medical records were reviewed for patients' age, fracture type, gender, anesthesia type and occurance of cut-out complication. Postoperatively taken radiographs were reviewed for tip-apex distance, obtained collo-diaphyseal angle, the quadrant of the helical blade and Ikuta reduction subgroup. The most important factor (s) and also predicted probability of cut-out complication was calculated for each combination of factors.

RESULTS

Cut-out complication was observed in 14 patients (4.7 %). The most important factor about occurrence of the cut-out complication was found as varus reduction (p: 0.01), the second important factor was found as implantation of the helical blade in the improper quadrant (p: 0.02). Tip-apex distance was found as third important factor (p: 0.10). The predicted probability of cut-out complication was calculated as 45.6 % when whole of the four surgeon dependent factors were improperly obtained.

CONCLUSION

Althought obtaining proper tip-apex distance is important to prevent cutout complication in these fractures, if the fracture is not reduced in varus position and helical blade is inserted in the proper quadrant, possibility of cut-out complication is very low even in the patients with high tip-apex distance.

Fast and easy preoperative estimation of cancellous bone mineral density in patients with proximal femur fractures

INTRODUCTION

Postoperative complications after hip fractures in osteoporotic bone such as implant cutout can be reduced by the use of specially designed implants or additional cement augmentation. It is not yet clear at which degree of osteoporosis, patients will profit from implant augmentation or specially designed implants for geriatric patients. As the surgeon ideally should obtain information on local bone quality at the site of implant anchorage already preoperatively, the aim of the study was to develop an easily applicable radiographic method to estimate bone quality in those patients.

MATERIALS AND METHODS

75 patients with unilateral hip fracture were included. Preoperatively, a CT scan with a calibration device was conducted. Postoperatively, DXA scans were performed. The proposed method measures local cancellous bone mineral density in the contralateral and uninjured femoral head. As a control, 15 young and healthy non-osteoporotic subjects were included. Inter- and intraobserver reliability was investigated for a subgroup of 20 patients.

RESULTS

Study group patients had a mean BMD measured by CT scans of 194.2 mg/cm(3) (SD 40.4). There was a statistically significant correlation with data from DXA scans (r = 0.706, p < 0.001). The control group was significantly younger and showed a significantly higher BMD when compared to the study group (p < 0.001). Reliability evaluation showed no statistically significant difference in inter- and intraobserver measurements. Interclass correlation proved to be very high.

CONCLUSION

The proposed method is an easily applicable, reliable and useful tool to estimate bone quality preoperatively using the contralateral hip as a reference. Obtained data may facilitate the decision-making towards the use of further therapeutic measures to improve implant anchorage in osteoporotic bone such as bone cement augmentation. Thus, our method allows for a more individualized surgical treatment of hip fracture patients adapted to the estimated cancellous bone quality of the patient.

[Proximal femoral fractures in the elderly]

Proximal femoral fractures represent an increasing major healthcare problem due to the demographic changes in this aging population and are associated with the highest mortality among fractures in elderly patients after suffering insufficiency injuries (so-called fragility fractures). The main aim in the treatment of orthogeriatric patients who suffered from a proximal femoral fracture is the preservation of function and independency. Given the high prevalence of comorbidities in these patients, interdisciplinary and interprofessional approaches are required. The use of modern osteosynthesis procedures can provide an improved, individualized surgical treatment with early full weight bearing of the affected extremity. Another aspect is the accompanying geriatric treatment which is associated with a significant reduction of perioperative and postoperative complications. In addition to acute treatment, the organization of secondary fracture prevention is a crucial pillar of treatment. This article provides an overview of the essential elements of orthogeriatric trauma surgery in elderly patients following proximal femoral fractures.

Is the cortical thickness index a valid parameter to assess bone mineral density in geriatric patients with hip fractures?

INTRODUCTION

Reduced bone quality is a common problem during surgical fixation of geriatric hip fractures. The cortical thickness index (CTI) was proposed to assess the bone mineral density (BMD) of the proximal femur on the basis of plain X-rays. The purpose of this study was to evaluate the inter- and intraobserver reliability of the CTI and to investigate correlation between CTI and BMD in geriatric patients.

METHODS

60 patients (20 pertrochanteric fractures, 20 femoral neck fractures, 20 without fractures) were included. All patients had ap and lateral hip X-rays and measurement of BMD by Dual Energy X-ray Absorptiometry at different areas of the hip. The ap and lateral CTI was measured twice by four blinded observers and correlation between mean CTI and BMD was calculated.

RESULTS

Mean ap CTI was 0.52 and mean lateral CTI was 0.45. Inter- and intraobserver reliability was good for ap CTI (ICC 0.71; 0.79) and lateral CTI (ICC 0.65; 0.69). A significant correlation between CTI and overall BMD was found in patients without fractures (r = 0.74; r = 0.67). No significant correlation between CTI and overall BMD was found in patients with proximal femoral fractures.

CONCLUSION

The CTI has sufficient reliability for the use in daily practice. It showed significant correlation with BMD in patients without hip fractures. In patients with proximal femoral fractures, no correlation between CTI and BMD was found. We do not recommend the CTI as parameter to assess the BMD of the proximal femur in geriatric patients with hip fractures.

Does metaphyseal cement augmentation in fracture management influence the adjacent subchondral bone and joint cartilage?: an in vivo study in sheep stifle joints

Augmentation of implants with polymethylmethacrylate (PMMA) bone cement in osteoporotic fractures is a promising approach to increase implant purchase. Side effects of PMMA for the metaphyseal bone, particularly for the adjacent subchondral bone plate and joint cartilage, have not yet been studied. The following experimental study investigates whether subchondral PMMA injection compromises the homeostasis of the subchondral bone and/or the joint cartilage.Ten mature sheep were used to simulate subchondral PMMA injection. Follow-ups of 2 (4 animals) and 4 (6 animals) months were chosen to investigate possible cartilage damage and subchondral plate alterations in the knee. Evaluation was completed by means of high-resolution peripheral quantitative computed tomography (HRpQCT) imaging, histopathological osteoarthritis scoring, and determination of glycosaminoglycan content in the joint cartilage. Results were compared with the untreated contralateral knee and statistically analyzed using nonparametric tests.Evaluation of the histological osteoarthritis score revealed no obvious cartilage damage for the treated knee; median histological score after 2 months 0 (range 4), after 4 months 1 (range 5). There was no significant difference when compared with the untreated control site after 2 and 4 months (P = 0.23 and 0.76, respectively). HRpQCT imaging showed no damage to the metaphyseal trabeculae. Glycosaminoglycan measurements of the treated joint cartilage after 4 months revealed no significant difference compared with the untreated cartilage (P = 0.24).The findings of this study support initial clinical observation that PMMA implant augmentation of metaphyseal fractures appears to be a safe procedure for fixation without harming the subchondral bone plate and adjacent joint cartilage.

Augmented screws in angular stable plating of the proximal humerus: what to do when revision is needed?

BACKGROUND

Bone cement augmentation of modified cannulated locking screws shows biomechanically and clinically good results for osteoporotic fracture management. Nevertheless, complications need to be considered. Therefore implant removal should be tested for feasibility.

METHODS

Implant removal was simulated in 7 pairs of osteoporotic cadaveric humeri: During screw removal from an angular stable proximal humerus plate, we measured the maximum torque of 14 augmented screws and the corresponding 14 non-augmented screws on the contralateral humeri. After screw removal, specimens were cut along the screw axes to macroscopically investigate the impact of screw removal on the surrounding bone. In addition, we established a technique for cement removal in cases in which the screw head is obstructed with cement and therefore disables the insertion of the screwdriver.

FINDINGS

The screw extraction torque measurements showed no significant differences between the two groups regarding one screw (screw 4 augmented: 1.52Nm, SD 0.25Nm vs. screw 4 non-augmented: 1.80Nm, SD 0.40Nm; P=0.20), whereas torque values for the second screw in the augmented group were lower than in the control group (screw 5 augmented: 0.72Nm, 0.31Nm vs. screw 5 non-augmented: 1.42Nm, 0.52Nm; P=0.009). Macroscopy of the bone showed no damage to the trabeculae within the humeral head due to the removal.

INTERPRETATION

The removal of cannulated, polymethylmethacrylate-augmented, 2.8mm titanium screws from an angular stable plate was uncomplicated, without the need for special instruments or increased torque for screw removal. No additional damage was visible at the bone-cement interface.

Implant augmentation: adding bone cement to improve the treatment of osteoporotic distal femur fractures: a biomechanical study using human cadaver bones

The increasing problems in the field of osteoporotic fracture fixation results in specialized implants as well as new operation methods, for example, implant augmentation with bone cement. The aim of this study was to determine the biomechanical impact of augmentation in the treatment of osteoporotic distal femur fractures.Seven pairs of osteoporotic fresh frozen distal femora were randomly assigned to either an augmented or nonaugmented group. In both groups, an Orthopaedic Trauma Association 33 A3 fractures was fixed using the locking compression plate distal femur and cannulated and perforated screws. In the augmented group, additionally, 1 mL of polymethylmethacrylate cement was injected through the screw. Prior to mechanical testing, bone mineral density (BMD) and local bone strength were determined. Mechanical testing was performed by cyclic axial loading (100 N to 750 N + 0.05N/cycle) using a servo-hydraulic testing machine.As a result, the BMD as well as the axial stiffness did not significantly differ between the groups. The number of cycles to failure was significantly higher in the augmented group with the BMD as a significant covariate.In conclusion, cement augmentation can significantly improve implant anchorage in plating of osteoporotic distal femur fractures.