An intuitive and simple technique for accurate insertion point selection and precise Poller (blocking) screw insertion.

Although indirect reduction with intramedullary (IM) nailing is the gold standard for long bone fractures, IM nailing in meta-diaphyseal fractures often results in malalignment. Placement of Poller (blocking) screws is an attractive and useful technique in these situations; however, the selection of accurate placement points and the placement process itself are often complicated. This paper proposes an intuitive, simple, and clear technique for selecting the location of Poller screw placement that can be used in either the anteroposterior or lateral view regardless of the fracture type and discusses techniques for Poller screw placement that enable displacement correction.

The Poller Screw Technique: A Method of Fine-Tuning the Reduction in Locked Nailing.

Intramedullary nailing is the treatment of choice for diaphyseal fractures in long bones. However, nailing of long bone fractures at the metaphyseodiaphyseal junction is technically difficult and can cause malalignment because of the mismatch in the diameter of the bone. One of the most common and recently described methods of correcting deformity during nailing is the poller screw technique. We describe a modified technique to correct malreduced fractures with the nail in situ, which we have used successfully in 3 patients.

Exchange nailing with enhanced distal fixation is effective for the treatment of infraisthmal femoral nonunions.

INTRODUCTION: The treatment options for nonunions of infraisthmal femoral shaft fractures after internal fixation are controversial. Methods such as exchanging an existing nail with a nail of a larger size, dynamization, removal of the nail followed by plating, and bone grafting have all been reported. Among those options, exchange nailing seems to be the most popular choice. In this study, a Poller screw, or an additional interlocking screw, was used in conjunction with exchange intramedullary nailing. The purpose of this study was to evaluate the effectiveness of treating femoral shaft nonunions using insertion of a Poller screw or an additional interlocking screw in conjunction with intramedullary nail fixation. MATERIALS AND METHODS: This study included 18 patients who presented with nonunion of femur shaft fractures after internal fixation at the infraisthmal level. These patients included 13 men and 5 women, with a mean age of 46.8 years (range 15-78 years). The mean postsurgical period of nonunion was 7.8 months (range 6-12 months). The patients were classified into two groups: the atrophic nonunion group and the hypertrophic nonunion group. In all patients, nailing was enhanced with a Poller screw or additional interlocking screws. All patients were followed up with plain film examinations and were assessed for their functional recovery status to determine the osseous union conditions. RESULTS: All 18 patients achieved postoperative bony union after a mean time of 7.5 months (range 3-12 months), and all patients were able to walk with full weight-bearing and without pain within 3 months. There were no significant complications, such as broken hardware, implant back-outs, axial or rotational malalignments, or deep infections. CONCLUSION: Poller screws and additional interlocking screws, along with intramedullary nailing exchange, may be an effective and reliable alternative for treating infraisthmal femoral shaft nonunions.

Challenge to treat hypertrophic nonunion of the femoral shaft: the Poller screw augmentation technique.

The management of a femoral nonunion after intramedullary nailing is challenging. Exchange nailing or plate augmentation has been used to treat hypertrophic nonunions previously. The Poller screw augmentation technique is a simple procedure that can be performed in the outpatient surgery. In this study, we highlight the method of hypertrophic nonunion management according to the specific indication including our Poller screw augmentation technique.

The evolution of poller screws.

Compared to other techniques, poller screws with intramedullary nailing are technically simple, practical, and reproducible for the fixation of metaphyseal fractures. In addition, poller screws do not require special instruments or hardware and are minimally invasive. This review takes a historical perspective to evaluate poller screws holistically. A non-systematic search on PubMed was performed using 'Poller screw' or 'Blocking screw' to find early use of poller blocking screws. Relevant references from these primary studies were then followed up. In 1999, Krettek et al. first coined the term poller screws after the small metal bollards that block and direct traffic. Poller screws were introduced as an adjunct to aid the union of metaphyseal long bone fractures during intramedullary nailing. However, as more evidence was published, the true effectiveness of poller screws was not appreciated, leading to split opinions. Through our research, we have built upon our understanding of poller screws, and we present a novel classification of poller screws over the years while exploring our novel technique and what we believe to be the fourth generation of poller screws. Currently, there is a paucity of research focussing on poller screws. However, studying the original evidence regarding poller screws through the most recent articles has demonstrated a confusion of research in this field. Therefore, we suggest a more organised approach to classify the use of poller screws.

Efficacy of poller screw in addition to lag screw in the treatment of intertrochanteric fractures with proximal femoral nail: a biomechanical evaluation.

PURPOSE: The most common type of failure in treating intertrochanteric fractures with proximal femoral nails is cut-out due to varus collapse. We aim to evaluate the effect of the poller screw applied to the proximal fragment and the lag screw on varus collapse and stability in intertrochanteric fractures. METHODS: An unstable intertrochanteric fracture model without medial support was simulated in 20 synthetic femur models. In the poller screw group, in addition to the lag screw, pole screws were applied to the proximal fragment superior and inferior to the lag screw. In the progressive cyclic loading test, starting from 100 N, the loading was increased by 50 N in each cycle, and the test was continued until the maximum load at which failure occurred as a result of conditioning cycles and progressive cyclic loading tests, stiffness, type of failure, force at failure, lag screw displacement, and varus collapse were recorded. RESULT: The average stiffness was found to be 124.705 N/mm in the poller screw group and 102.77 N/mm in the control group (P < 0.001). The maximum load to failure was 1897.10 N in the poller screw group and 1475.20 N in the control group (P < 0.001). The average displacement of the lag screw within the femoral head was 0.85 mm in the poller screw group and 3.60 mm in the control group (P < 0.001). CONCLUSION: As a result, it has been shown that poller screws applied around the lag screw increase fixation stiffness and reduce varus collapse.

Poller Screws and Post-Operative Pain Relief in Tibial Fractures.

Introduction Poller screws optimise fracture alignment in those fractures managed with intramedullary (IM) nails. They enhance stability, control nail insertion, and prevent translation. Indications encompass acute fractures, delayed unions/non-unions, and deformity. Classified into four generations, they've shown positive outcomes: improved alignment, reduced complications, and shorter healing. However, their pain management impact is understudied. This retrospective cohort study aimed to compare opioid medication needs in tibial fractures managed with IM nails with and without poller screws. Methods Between January 2015 and December 2022, a retrospective analysis was conducted on tibial fractures treated at a major trauma centre. Patients primarily treated with IM nails were included. Patient and operation notes as well as radiographs, were reviewed to identify poller screw utilisation. Opioid medication data was collected and converted to "coverage" (days) and "strength" (morphine milligrams equivalent or MME). Two-tailed independent samples T-tests were performed to determine differences between patients treated with (n=205) and without poller screws (n=540). Results Patients with poller screws had fewer days with opioid prescriptions in the second post-operative month (6.8 vs. 8.9 days, p=0.038) and significantly lower opioid strength requirements across the first post-operative year (688.4 vs. 1295.4 MME, p=0.001), except the first month. Conclusion There is limited research on the connection between poller screws and pain. This study discusses their potential to reduce post-operative pain in tibial fractures. The results highlight the importance of using poller screws alongside IM. This combination appears to be effective in improving post-operative pain management and enhancing overall patient outcomes.

In silico biomechanical analysis of poller screw-assisted small-diameter intramedullary nail in the treatment of distal tibial fractures.

Objective: To evaluate the biomechanical effects of Poller screws (PS) combined with small-diameter intramedullary nails in the treatment of distal tibial fractures at different locations and on different planes. Methods: Nine finite element (FE) models were used to simulate the placement of the intramedullary nail (IMN) and the PS for distal tibial fractures. Structural stiffness and interfragmentary motion (IFM) through the fracture were investigated to assess the biomechanical effects of the PS. The allowable stress method was used to evaluate the safety of the construct. Results: With the axial load of 500 N, the mean axial stiffness of IMN group was 973.38 ± 95.65 N/mm, which was smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). The shear IFM of the IMN group was 2.10 ± 0.02 mm, which were smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). Under physiological load, the stresses of all internal fixation devices and the nail-bone interface were within a safe range. Conclusion: In the treatment of distal tibial fractures, placing the PS in the proximal fracture block can obtain better biomechanical performance. The IMN fixation system can obtain higher structural stiffness and reduce the IFM of the fracture end by adding PS.

Blocking screw augmentation in intramedullary nailing for displaced surgical neck fractures of the proximal humerus.

A displaced surgical neck fracture can be a good indication for antegrade intramedullary nailing. However, nail insertion may result in malreduction and translational displacement of the humeral head fragment because of muscle traction and size discrepancies between the diameters of the medullary canal and the intramedullary nail. We used blocking screw augmentation in 20 fractures with residual medial displacement of the distal fragment after nail insertion to anatomically reduce displacement of the fracture and to maintain the reduced position before bone union. A blocking screw was placed percutaneously at the lateral side of the canal. Next, a straight intramedullary nail was reinserted medial to the blocking screw. Finally, the nail was locked both proximally and distally. All cases showed bone union without fixation failure at the time of the final follow-up. Blocking screw augmentation with intramedullary nailing is feasible for the treatment of humeral surgical neck fractures and is thought to be helpful for fracture reduction during surgery and stable fixation after surgery.

Poller (blocking) screw with intramedullary femoral nailing for subtrochanteric femoral non-unions: clinical outcome and review of concepts.

INTRODUCTION: Surgery to treat nonunion resulted from malalignment is challenging since correction and bone union should be achieved simultaneously. To report the clinical outcomes achieved through reconstruction of sub-trochanteric femoral fractures by femoral nailing using a poller screw and to review the current concepts. MATERIALS AND METHODS: Fourteen patients (11 men and 3 women; mean age 56.4 years) who were diagnosed with non-union of subtrochanteric femoral fractures and who underwent intramedullary nailing with blocking screws between August 2013 and March 2019, with at least 1 year follow-up, were analyzed retrospectively. The preoperative and postoperative Centrum-Collum-Diaphyseal angle and anterior angulation angle were measured. Bone union time, position and number of poller screws used, and complications were analyzed. Functional assessment was performed by evaluating the Harris hip score. The related literature was searched, and 14 clinical studies on the treatment of sub-trochanteric non-union were analyzed. RESULTS: Bone union was achieved in 12/14 cases (85.7%) at the final follow-up within a mean of 6.52 (3-12) months. Bone union was also achieved in two patients lacking bone union at the final follow-up through bone grafting and augmented plating. No cases developed complications, including infection and bone necrosis, and the varus deformity and anterior angulation significantly improved from a preoperative mean of 12.4° and 9.4° to postoperative mean 3.8° and 2.4°, respectively. The mean Harris hip score at the final follow-up was 87.07 (73-98) points. Analysis of published literature revealed high rates of bone union (78-100%) through various fixation methods. CONCLUSION: Correction with blocking screws and rigid fixation with intramedullary nailing to treat sub-trochanteric-non-union-caused malalignment can yield good clinical and radiological outcomes.

Do Poller screws effect union in tibial shaft fractures treated with intramedullary nailing?

INTRODUCTION: Tibial shaft fractures are a commonly encountered challenge presented to orthopaedic trauma surgeons. Intramedullary nailing (IMN) is often the treatment of choice and whilst effective, complications of delayed and/or non-union can cause significant morbidity and necessitate additional operative procedures. The use of Poller screws during IMN are a recognised way of aiding fracture reduction, however the clinical benefits of this are debated. This study evaluated the outcome of tibial shaft fractures treated with IMN with or without the addition of Poller screws. METHODS: Retrospective cohort study of all patients undergoing IMN following tibial shaft fractures over a 5-year period. 154 operated tibial shaft fractures were identified, with patients divided into 3 groups - Group 1: IM nailing alone, Group 2: IMN + 1 conventional Poller screw, or Group 3: IMN + 2 Poller screws placed Epicentrically across the fracture site. Data collected included demographics, length of stay, fracture type, position and AO classification grade, operative time, and operating surgeons' grade. Primary outcome measure was the incidence of delayed and/or non-union. Secondary outcomes were differences in rates of infection and additional orthopaedic procedures between the 3 groups. RESULTS: Overall 139/154 fractures (90.3%) achieved a timely union. There was a statistically significant difference (p = 0.05) in fracture union between the 3 groups, with 75/88 fractures healing in group 1 (IMN alone) compared to 44/46 in Group 2 (IMN + 1 Poller screw) and 20/20 in group 3 (IMN + 2 Poller screws). There was no statistical difference in the incidence of superficial infection, (p = 0.95) additional procedures (p = 0.23) or deep infection (p = 0.65) between the 3 groups. CONCLUSION: The addition of Poller screws appear to be a safe and effective adjunct in the treatment of tibial shaft fractures via IMN. Further prospective randomised trials are needed to fully elucidate both the role and potential benefits of Poller screw augmentation in acute lower limb fracture management.

Systematic review on the outcomes of poller screw augmentation in intramedullary nailing of long bone fracture.

Various technical tips have been described on the placement of poller screws during intramedullary (IM) nailing; however studies reporting outcomes are limited. Overall there is no consistent conclusion about whether intramedullary nailing alone, or intramedullary nails augmented with poller screws is more advantageous.We conducted a systematic review of PubMed, EMBASE, and Cochrane databases. Seventy-five records were identified, of which 13 met our inclusion criteria. In a systematic review we asked: (1) What is the proportion of nonunions with poller screw usage? (2) What is the proportion of malalignment, infection and secondary surgical procedures with poller screw usage? The overall outcome proportion across the studies was computed using the inverse variance method for pooling.Thirteen studies with a total of 371 participants and 376 fractures were included. Mean follow-up time was 21.1 months. Mean age of included patients was 40.0 years. Seven studies had heterogenous populations of nonunions and acute fractures. Four studies included only acute fractures and two studies examined nonunions only.The results of the present systematic review show a low complication rate of IM nailing augmented with poller screws in terms of nonunion (4%, CI: 0.03-0.07), coronal plane malunion (5%, CI: 0.03-0.08), deep (5%, CI: 0.03-0.11) and superficial (6%, CI: 0.03-0.11) infections, and secondary procedures (8%, CI: 0.04-0.18).When compared with the existing literature our review suggests intramedullary nailing with poller screws has lower rates of nonunion and coronal malalignment when compared with nailing alone. Prospective randomized control trial is necessary to fully determine outcome benefits. Cite this article: EFORT Open Rev 2020;5:189-203. DOI: 10.1302/2058-5241.5.190040.

Regenerate Deformity with the Precice Tibial Nail.

Limb lengthening by distraction osteogenesis is an accepted orthopaedic surgical technique. The Precice intramedullary lengthening system is the most recent innovation in limb lengthening. Early results have been favourable in femoral lengthening but there is little reported on the outcome in tibial lengthening. The aim of this study is to present our early results of Precice tibial lengthening, and the stepwise evolution of our surgical technique. MATERIALS AND METHODS: A case series of 17 consecutive tibial lengthenings were prospectively analysed. Healing index, length achieved, range of motion, and complications were recorded. The initial cases followed the recommended surgical technique. Progressive regenerate deformity during lengthening required changes to the surgical method. RESULTS: No cases were lost to follow-up. All the nails lengthened at the desired rate. There were no complications of infection or poor regenerate formation. Progressive valgus and procurvatum was prevented in later cases by the positioning of Poller blocking screws at the time of nail insertion. CONCLUSION: The tibial Precice nail is successful in obtaining length and good regenerate formation. The recommended technique was insufficient to control the deforming forces from the lower limb muscle compartments during lengthening. We therefore recommend the addition of multiple blocking screws in an amended technique. HOW TO CITE THIS ARTICLE: Wright SE, Goodier WD, Calder P. Regenerate Deformity with the Precice Tibial Nail. Strategies Trauma Limb Reconstr 2020;15(2):98-105.

Does the Use of Blocking Screws Improve Radiological Outcomes Following Intramedullary Nailing of Distal Tibia Fractures?

AIM: The aim of this study is to assess whether the addition of blocking screws during intramedullary nailing of a distal tibia fracture improved the radiological outcome and prevented a loss of fracture alignment. As a secondary outcome, the time to radiographic union was compared to see if a more rigid bone-implant construct had an effect on healing. METHODS: We searched computerized records at a UK level 1 major trauma center. The joint alignment was measured on the immediate postoperative radiograph and compared to the most recent radiograph. We used a difference of 2° to indicate a progressive deformity. RESULTS: Thirty patients were included. Twenty patients had no blocking screw and 10 patients had a blocking screw. Six patients had a difference in their coronal plane alignment of 2° or more (3/6 had no blocking screw). The results were analyzed and found to be not statistically significant (p = 0.82). The addition of a blocking screw has also been shown not to have an effect on the time to radiological union (RUST score greater or equal to 10). CONCLUSION: We use a 2.5-mm blocking wire to aid in fracture reduction prior to reaming or nail insertion and then remove the wire when the nail has been adequately locked. We no longer routinely replace the wire with a blocking screw and this could lead to a decrease in procedure time, cost, and radiation exposure. HOW TO CITE THIS ARTICLE: Fawdington RA, Lotfi N, Beaven A, et al. Does the Use of Blocking Screws Improve Radiological Outcomes Following Intramedullary Nailing of Distal Tibia Fractures? Strategies Trauma Limb Reconstr 2019;14(1):11-14.

Blocking Screw-assisted Intramedullary Nailing Using the Reverse-rule-of-thumbs for Limb Lengthening and Deformity Correction.

INTRODUCTION: Historically, blocking screws have been used to assist in acute reduction of fractures during intramedullary (IM) nailing. The reverse-rule-of-thumbs (RROT) for blocking screws was introduced to facilitate internal lengthening nail use in deformity correction and limb lengthening. Our study investigated the ability of blocking screws, using same principle, to accurately correct long-bone deformity with and without lengthening and to prevent lengthening-induced deformity. MATERIALS AND METHODS: This is an institutional review board (IRB)-approved retrospective study on 86 patients who had IM nail-assisted limb reconstruction of femur or tibia with blocking screws. Surgeries were performed for deformity correction, limb lengthening, or deformity correction and limb lengthening. Data on the following variables were collected: number of blocking screws, distance of each blocking screw to osteotomy, distance of osteotomy from joint line, and amount of lengthening. Mechanical axis deviation (MAD) and joint alignment parameters were measured preoperatively and at the final postoperative follow-up. The primary outcome was the ability to obtain desired MAD and joint orientation angles. Accuracies were reported as postoperative measurements relative to goal. Association for the Study and Applications of the Methods of Ilizarov (ASAMI) scores were collected. RESULTS: The accuracy of deformity correction was within 6 mm from goal, while joint orientation was corrected to within 1.5° of goal. Number of blocking screws did not significantly impact accuracy. Distance of blocking screw to osteotomy and amount of lengthening did not affect accuracy. In femurs, osteotomies greater than 10 cm from the joint line were more accurate in MAD goal (p = 0.017). This result was not replicated in tibias. ASAMI scores were excellent or good. CONCLUSION: Using RROT configuration, blocking screws were effective in correcting deformities of lower extremity long bones and in preventing deformity during limb lengthening. If positioned correctly, number of screws and their distance to osteotomy did not affect accuracy. Amount of lengthening did not impact accuracy. Distal femoral osteotomy less than 10 cm from knee joint may be challenging even with using blocking screws. HOW TO CITE THIS ARTICLE: Dabash S, Zhang DT, Rozbruch SR, et al. Blocking Screw-assisted Intramedullary Nailing Using the Reverse-rule-of-thumbs for Limb Lengthening and Deformity Correction. Strategies Trauma Limb Reconstr 2019;14(2):77-84.

Blocking screws for alignment control in intramedullary limb lengthening.

Simultaneous deformity correction in the frontal and sagittal plane becomes more and more an important part of intramedullary lengthening to avoid further operative procedures. Such as in fracture treatment blocking screws can be used for alignment control if osteotomy is performed in the metaphyseal bone. 31 intramedullary lengthening procedures between 2009 and 2011 were retrospectively analysed for precision of simultaneous deformity correction. The average planned correction to the HKA was 2.4° (0.1°-8.0°) and the final results after lengthening deviated an average of 1.7° (0.0°-8.1°) from the planning. With blocking screws a higher degree of deformity (mean 3.2° vs. 1.7°; p<0.05) was corrected with a slightly higher precision (mean 1.5° vs. 1.9°; p=0.48) compared to patients without blocking screws. Placed on the concave side of the deformity blocking screws are a helpful tool to successfully address leg length discrepancy and other deformities with one single operation.

A novel technique for accurate Poller (blocking) screw placement.

Achieving good results with intramedullary nailing of oblique long bone fractures at the metaphyseal-diaphyseal junction can be difficult. There is a strong tendency for axial displacement and an association with characteristic malalignment of the short fragment. Poller or blocking screws have been shown to be effective in aiding fracture reduction. While several papers describe methods for screw placement, these are confusing to understand, difficult to follow in clinical practice and not always applicable. Here we describe a new, simple, reproducible and easy to use method for ensuring accurate Poller screw placement, in order to maximise the benefits of their use and achieve good overall results.

The Usefulness of Poller Screw with Antegrade Nailing in the Initial Treatment of Infraisthmal Femur Shaft Fracture

PURPOSE: The purpose of this study was to evaluate the radiologic and clinical outcomes after intramedullary nailing with Poller screw insertion at initial stage in infraisthmal femur shaft fractures. MATERIALS AND METHODS: Seven consecutive patients (7 femurs) treated with antegrade intramedullary nailing with Poller screw insertion for the infraisthmal femur shaft fracture were reviewed retrospectively. There were 4 male and 3 female patients. Mean age was 46.1 years (20-72 years). Operative time including Poller screw insertion, time for union, malalignment, and range of motion were evaluated. RESULTS: All 7 cases had primarily healed successfully. Mean time for radiologic union was 19.1 weeks (16-24 weeks) postoperatively. One case had 5 degree valgus malalignment. One case of 15 mm shortening was reported and he required shoe lift orthosis. All cases had a full range of motion in hip and knee joint. CONCLUSION: Antegrade intramedullary nailing with Poller screw insertion is useful in the initial treatment of infraisthmal femur shaft fracture, because it could provide additional stability. An additional 20 minutes were required but a Poller screw should be considered according to the anatomic location of a femur shaft fracture.

The Use of Poller Screws in Nonunion of Femoral Shaft Following Intramedullary Nailing of Femoral Shaft Fracture: A Case Report / 대한정형외과학회잡지

As intramedullary nailing became more common in the treatment of femur shaft fractures, the incidence of nonunion increased which led to various treatment modalities for this complication. Accurate diagnosis of the etiology of nonunion and appropriate treatment is essential. Poller screws can help in preventing possible sagittal malalignment after intramedullary nail fixation and also be a minimally invasive method to treat hypertrophic nonunion derived from bone fragment mobility. We report 1 case along with literature review for the treatment of hypertrophic nonunion in femur.

Treatment of Proximal Shaft Fracture of Tibia with Intramedullary Nail: Analysis According to AO Classification and the Poller Screw

PURPOSE: This was a retrospective study to evaluate the results of intramedullary nailing in proximal shaft fracture of tibia. We analyzed those results according to AO classification and Poller screw. MATERIALS AND METHODS: Thirty-three proximal tibial shaft fractures (32 patients) were followed for more than one year. In AO classification, there were 6 cases of type A, 14 cases of type B, and 13 cases of type C. We used Poller screws in 14 operations. We evaluated translation, angulation and nonunion after surgeries. RESULTS: Twenty-eight cases (85%) were united primarily, but nonunions occurred in 5 cases. Malalignment (angulation>5degree or translation>5 mm) was found in 14 cases (42%). In Poller screw used and non-used groups, the malalignment was respectively showed in 2 cases (14%) and 12 cases (63%). According to AO classification, nonunion was found in only type B with 5 cases (36%). CONCLUSION: Intramedullary nailing of proximal shaft fracture of tibia showed relatively lower rate of primary union. Especially, when initial fractures have a butterfly fragment, it showed the higher rate of nonunion. Moreover, the malalignment rate was relatively higher, yet it is possible to reduce the rate of malalignment by using Poller screw.