``Sandwich technique" with dual strut allograft in surgical treatment of femoral nonunion.

OBJECTIVE: The treatment of femoral nonunion is challenging for both the surgeon and the patient. Strut allografts increase the bone stock, enhance fracture healing and increase stability by acting as a biological plate. In this study, we aimed to report the results of the sandwich technique with two-strut allograft in the treatment of oligotrophic or atrophic femoral nonunions. METHODS: Medical records of the patients who were treated due to femoral nonunion in a single center were retrospectively reviewed. Twenty-one patients (10 males, 11 females) with a mean age of 49 (range: 21 to 79) years were included in the study. The left side was affected in 11 patients, whereas the right side was affected in ten. The patients had 11 femoral shaft fractures, seven proximal femoral fractures and three distal femoral fractures. The mean time from the previous operation to the nonunion surgery was 9.6 (range: 6 to 22) months. RESULTS: Union was achieved in all patients after a mean period of 6.2 (range: 4 to 10) months. The mean follow-up time was 46.8 (range: 12 to 86) months. One patient had superficial surgical site infection in the autologous graft donor site. CONCLUSION: The sandwich technique with two-strut allograft provides good results in the treatment of femoral nonunion. The technique can be used on any type of nonunion, at any segment of the femur and can be combined with different fixation techniques.

Biomechanics of Osteoporotic Fracture Fixation.

PURPOSE OF REVIEW: Fractures of osteoporotic bone in elderly individuals need special attention. This manuscript reviews the current strategies to provide sufficient fracture fixation stability with a particular focus on fractures that frequently occur in elderly individuals with osteoporosis and require full load-bearing capacity, i.e., pelvis, hip, ankle, and peri-implant fractures. RECENT FINDINGS: Elderly individuals benefit immensely from immediate mobilization after fracture and thus require stable fracture fixation that allows immediate post-operative weight-bearing. However, osteoporotic bone has decreased holding capacity for metallic implants and is thus associated with a considerable fracture fixation failure rate both short term and long term. Modern implant technologies with dedicated modifications provide sufficient mechanical stability to allow immediate weight-bearing for elderly individuals. Depending on fracture location and fracture severity, various options are available to reinforce or augment standard fracture fixation systems. Correct application of the basic principles of fracture fixation and the use of modern implant technologies enables mechanically stable fracture fixation that allows early weight-bearing and results in timely fracture healing even in patients with osteoporosis.

Intra-prosthetic dislocation of dual mobility hip prosthesis: an original and unusual complication.

A 78-year-old female presented with dislocation of a dual mobility hip prosthesis. On standard radiographs after closed reduction, the hip prosthesis appeared to be properly reduced, but clinically the hip was unstable. A Computed Tomography showed a round foreign body, that was in fact a dislocation of the intra-prosthetic implant. This was confirmed intra-operatively during revision surgery. Intra-prosthetic dislocation is a specific complication of dual mobility system. Classically, it's a late complication, linked to the wear of retention area of the polyethylene insert. In this case report we describe an unusual reason of intra-prosthetic dislocation caused by a reduction maneuver of a dislocated dual mobility total hip prosthesis, which to our knowledge has never been documented with Computed Tomography imagery and intra operative pictures. The aim of this article is to analyse the advantages and complications of this implant and to establish recommendations. Dealing with an intra-prosthetic dislocation of a dual mobility hip prosthesis, we recommend attempting a reduction under general anesthesia to avoid mechanical complications. In case of persistent instability after reduction, we recommend performing a Computed Tomography scan.

Biomechanics of Periprosthetic Fixation: Plates, Nails, Cables, and Allografts.

Periprosthetic fractures (PPFs) present unique challenges to orthopaedic surgeons in terms of limited cortical fixation options, poor bone quality, cement mantles, and stress risers introduced from the prosthesis. Various fixation strategies have been used in PPFs including the use of intramedullary nails, locked plates, unicortical locking screws, cerclage wires and cables, double-plating techniques, and allograft struts. Here, we will review the biomechanics of various fixation strategies used in PPFs.

Cementing of the hip arthroplasty stem increases load-to-failure force: a cadaveric study.

Background and purpose - To date, there is not a single clinical or mechanical study directly comparing a cemented and a cementless version of the same stem. We investigated the load-to-failure force of a cementless and a cemented version of a double tapered stem. Material and methods - 10 femurs from 5 human cadaveric specimens, mean age 74 years (68-79) were extracted. Bone mineral density (BMD) was measured using peripheral quantitative computed tomography. None of the specimens had a compromised quality (average T value 0.0, -1.0 to 1.4). Each specimen from a pair randomly received a cemented or a cementless version of the same stem. A material testing machine was used for lateral load-to-failure test of up to a maximal load of 5.0 kN. Results - Average load-to-failure of the cemented stem was 2.8 kN (2.3-3.2) and 2.2 kN (1.8-2.8) for the cementless stem (p = 0.002). The cemented version of the stem sustained a higher load than its cementless counterpart in all cases. Failure force was not statistically significantly correlated to BMD (p = 0.07). Interpretation - Implanting a cemented version of the stem increases the load-to-failure force by 25%.

Locking plates versus retrograde intramedullary nails in the treatment of periprosthetic supracondylar knee fractures. A retrospective multicenter comparative study.

INTRODUCTION: Biomechanical studies demonstrated the superiority of retrograde supracondylar intramedullary nails (RIN) against locking plates (LP) for the treatment of periprosthetic supracondylar femoral fractures (PSFs); however, clinical results are still conflicting. This study aimed to compare LP and RIN, as well as, cemented and uncemented nails in the treatment of PSFs regarding fracture healing, complications and functional results. MATERIALS AND METHODS: A retrospective multicenter analysis of 60 PSFs classified as Rorabeck type I or II was performed. Thirty-one cases were treated with LP while in 29 cases RIN were used. Out of the latter, 14 had nailed cementoplasty, while 15 an uncemented nail. RESULTS: The two groups were comparable concerning gender, ASA score, operated side, follow-up time, fracture type and mechanism of injury. The LP was significantly younger than the RIN group. Forty-six cases had fracture union at an average of six months, 11 were healed between seven and twelve months (delayed unions), and three developed non-unions. There was no significant difference in the median union time between RIN and LP groups (six vs five months, p = 0.707) or cemented and uncemented nailing groups (5.5 vs six months, p = 0.354). The RIN group had fewer delayed unions or non-unions than LP group; however, not reaching significance (4 vs 10, p = 0.190). Complications were fewer but non-significantly different between cemented and uncemented nails (one vs five, p = 0.481). The mean postoperative flexion was comparable between RIN and LP groups (99.1° vs 94.9°, p = 0.547) or cemented and uncemented nails (102° vs 96.3°, p = 0.4). The mean Oxford Knee Score did not differ between LP and RIN groups (30.8 vs 31.3, p = 0.93) as well as between cemented and uncemented nails (31.5 vs 30.6, p = 0.801). DISCUSSION: PSFs with good bone stock can be treated equally with LP or RIN. Nails demonstrated advantages concerning the fracture healing potential. Orthopaedic surgeons need to be trained in both treatment options to manage PSFs. Cemented nails may increase stability and healing capacity in elderly osteoporotic patients; however, further studies are needed.

Outcomes of fixation for periprosthetic tibia fractures around and below total knee arthroplasty.

INTRODUCTION: The incidence of periprosthetic fractures after total knee arthroplasty (TKA) is rising due to an increasing number of TKAs performed annually and the growing elderly population. Like periprosthetic fractures of the distal femur, periprosthetic tibia fractures are primarily treated with operative fixation; however, there is limited scientific literature that has reported outcomes of periprosthetic tibia fractures treated with modern plating techniques. To our knowledge, this is the largest series of non-intraoperative periprosthetic tibia fractures treated with open reduction internal fixation (ORIF) ever reported. METHODS: Retrospective chart review of 4557 operatively treated tibia fractures with ORIF over a 16-year period at two Level 1 Trauma Centers. RESULTS: 38 patients with an average follow-up of 15.3 months (range 3-24) were identified. 11 (28.9%) fractures were in the proximal tibia (four with extension into the plateau (Felix 1A) and seven adjacent to the tibial stem (Felix 2A)), six (15.8%) in the midshaft/diaphysis (Felix 3A), and 21 (55.3%) in the distal 1/3rd (metaphysis, Felix 3A). 76.3% (29/38) of fractures united by 6 months following the index procedure, leaving 9 nonunions. The overall re-operation rate was 31.6% (12/38). There were no significant differences in rates of union (p = 1.00), reoperation (p = 0.66), superficial infection (p = 0.66), or deep infection (p = 0.31) in patients treated with single versus dual plating. CONCLUSION: Periprosthetic tibia fractures are difficult to treat and have a high risk of nonunion and reoperation even with modern plating techniques. Most patients can be treated to union with operative fixation and do not require revision arthroplasty, if the components are stable initially. We recommend dual plating for fractures in the proximal third, and either single plating or nailing for fractures in the middle and distal thirds depending on bone quality, implant positioning, and fracture morphology.

Diagnosis and management of periprosthetic femoral fractures after hip arthroplasty.

INTRODUCTION: Periprosthetic femoral fracture represent a severe complication, at present the third cause of revision surgery, with an estimated incidence from 0,1 to 2,1%. The number of these fracture can be expect to increase in line with the aging of population and amount of THA implants also in younger high demanding patients. MATERIALS AND METHODS: The aim of this study is analyze the diagnostic and therapeutic decision making processes performed in 64 patients with periprosthetic fractures treated surgically from January 2012 and October 2016 in our center. We analysed instrumental exams and surgical reports focusing on type of procedure, surgical access, operative time and type of fixation. RESULTS: Average age was 809 years and a mean follow-up 231 months. According to Vancouver system and after X-rays, CT scan and intraoperative evaluation, 26 fractures were classified as type B1, 31 as type B2, 3 type B3 and 4 type C. Follow up results were divided on the basis of the surgical treatment: in ORIF group (23 type B1 fractures and 4 type C fracture) fracture union was obtained in 16 cases (593%) and the final HHS mean value was 6161; in Revision group (3 type B1, 31 type B2 and 3 type B3) bone healing was reported in 26 cases (703%) with mean HHS score of 7194. CONCLUSIONS: In this surgery the objectives are provide an adequate bone healing and return to previous functional status as soon as possible. Many reasons make these goals challenging, in particular advanced age, osteoporosis, co-morbidity and weakness that lead to low energy trauma, the most frequent cause of these injuries. In our opinion a crucial aspect is the evaluation of stem stability, considering an implant mobilized until the opposite is clearly evident. Reduction of surgical time and early mobilization are goals of this surgery, often associated with several complications and high mortality rate.

Periprosthetic femoral fractures after total hip arthroplasty: An algorithm of treatment.

BACKGROUND: Periprosthetic femoral fractures (PFFs) following total hip arthroplasty are becoming more prevalent and management of these fractures is often demanding. The surgeon has to assess in detail implant loosening, bone loss and type of fracture. The aim of the study is to identify the suitability of a treatment algorithm, based on the Vancouver classification that takes into account the activity and comorbidity of each patient. PATIENTS AND METHODS: This study retrospectively assessed 38 patients who were surgically treated for a PFF around total hip arthroplasty between 2010 and 2014. All fractures were classified according to the Vancouver classification. There were 14 type B1, 8 type B2, 10 type B3 and 6 type C fractures. The data examined were age, sex, mechanism of injury, type of fracture, ASA score, type of surgery and complications. Radiographic evaluations were performed at 1, 3, 6 months and every 12 months thereafter. Clinical results were measured using the Merle-d'Aubigné-Postel score. Treatment options included an ORIF in 22 patients and a stem revision in 16 patients, with or without plates or supplemental cortical strut grafting when required. RESULTS: The mean duration of follow-up was 3.1 years, mean age was 71.2 years and six patients (15.7%) died. Union was obtained in all patients in a mean of 16 weeks. Three patients required a surgical revision: one for stem loosening and two for re-fracture after a new fall. One patient had varus malunion of the femur. The mean postoperative Merle-d'Aubigné-Postel score was 13.2. Thirteen patients showed excellent results, 14 had a good result, three had a fair outcome and two had a poor result. Twenty patients returned to their baseline mobility status, while 12 patients had either a decline in their ambulatory status or a need for additional assistive devices. CONCLUSIONS: PFF remains a serious complication of hip arthroplasty that is accompanied by high morbidity and mortality rates. This study shows how patients' comorbidities and functional demand can direct the proper treatment. This is a suitable algorithm for the treatment of PFF, which can provide satisfactory results in terms of pain and function.

Clinical outcome and quality of life of patients with periprosthetic distal femur fractures and retained total knee arthroplasty treated with polyaxial locking plates: a single-center experience.

PURPOSE: The number of total knee arthroplasties (TKA) increased rapidly. In conjunction with higher implantation rates, periprosthetic femur fractures following TKA are also gradually increasing. Purpose of this study was to evaluate polyaxial locking plate treatment of periprosthetic femoral fractures with retained total knee replacement using polyaxial locking plates in regard to quality of life, functional outcome and complications. METHODS: The Study design is a single-center retrospective cohort analysis. Included were patients with periprosthetic supracondylar femoral fractures with a well-fixed knee prosthesis initially treated with NCB plate (Non-contact bridging plate, Zimmer Inc., Warsaw, IN). Primary outcome was measured including quality of life and functional status using the SMFA-D score (German short musculoskeletal function assessment questionnaire), the mortality rate and union rate. Formerly published SMFA-data presenting representative randomly chosen cross-sectional data from general population of the USA and Dutch population was used as historic control group. RESULTS: In total, 45 patients with a mean age of 74 years were included (10 males; 35 females). Body mass index averaged 27.4 kg/m2. Follow-up averaged 52 months. Comparison of the SMFA-D scores showed higher scores according to bother index (41.5 vs. 15.7/13.8) and function index (42.5 vs. 14.5/12.7). Mortality rate was 26.7%. The CCI was directly related to the mortality rate (p = 0.033). Union was achieved in 35 of 45 fractures (78%) six months after the index procedure. The ultimate union rate including following procedures at last follow-up was 95.6%. CONCLUSION: Besides already highlighted limitations in range of motion, we quantified patient-related limitations in daily living. A large number of patients after surgery are not self-reliant mobile or on orthopedic aids. A high CCI was directly related to the mortality rate and can be used as a predictive factor for postoperative mortality.

Outcomes and predictors of mortality following periprosthethic proximal femoral fractures.

BACKGROUND: Periprosthetic fractures are a well-documented, serious complication of joint arthroplasty, occurring in up to 11% of hip replacements. We examined periprosthetic femoral fractures over an 8 year period to determine the demographics, fracture pattern and management options and associated outcomes. Furthermore, we sought to determine which comorbidities resulted in increased risk of 12 month mortality after periprosthetic fractures about hip replacements Methods: A retrospective review of a prospective fracture database was conducted for the years 2007-2015. The Fracture Outcomes Research Database (FORD) was interrogated for patients aged >60 years, admitted with periprosthetic hip fracture. Radiographic and Electronic Clinical Record review was performed to classify fractures, record treatments, comorbidies and 12 month mortality. A multivariate analysis was performed to determine comorbidities that significantly increased the risk of 12 month mortality. RESULTS: A total of 189 patients were identified. The majority were Vancouver B1 fractures (61.9%); the operations were primarily cable plating (75.1%), with a smaller number of revision arthroplasties (21.2%) and only three proximal femoral replacement (1.6%). Four patients (2.1%) died before surgery. Only 27.3% returned to their usual residence post-discharge. Overall 30-day mortality was 2.1%, and one-year mortality was 11.6%. Patients who died tended to be older. In the multivariate analysis, ASA grade III/IV and active neoplasia were significant contributors to 12 month mortality. CONCLUSION(S): Our 12 month mortality (11.6%) is at the lower end of existing reported literature, and serves as a benchmark for UK practice. In the multivariate analysis, only ASA grade III/IV and an active neoplastic process were significantly associated with increased risk of mortality. Whilst large, multicenter trials, utilizing standardized treatment techniques are required to fully assess risk factors for 12-month mortality, it appears that those at significant risk are elderly, frail individuals with an active malignancy.

Geriatric distal femoral fractures: A retrospective study of 30 day mortality.

INTRODUCTION: Distal femoral fractures have many of the same challenges as hip fractures, but there has been limited research into outcomes following these. The aim of this study was to assess 30 day mortality following distal femoral fractures in comparison to hip fractures presenting to a single institution Secondary outcomes included risk factors for mortality, post-operative complications and union. METHODS: A retrospective case series of all distal femoral fragility fractures in patients over 65, and hip fractures over a 5 year period at a single institution. RESULTS: 88 distal femoral fractures and 2837 hip fractures fulfilled the inclusion criteria. In the distal femoral fractures there were 80 females and 8 males with a mean age of 82.4 (range 65-103). The mean age of the hip fractures was 83.7 (range 65-106) and there were 2066 females and 771 males. The overall 30 day mortality for hip fractures was 7.7% and was 9.1% for distal femoral fractures. The risk ratio was 1.1777(95% CI 0.6009-2.3080) (p = 0.6338). There was no significant difference in 30 day mortality between the two fracture types. Of the 88 distal femoral fractures 75 (85.2%) underwent open reduction internal fixation, 5 (5.7%) intramedullary nail and 8 (9.1%) conservative treatment. 11.4% suffered a medical complication. 9.1% patients required at least 1 further surgical procedure. The union rate was 94.3%. The 1 year mortality was 34.1%. CONCLUSIONS: There is no significant difference in 30 day mortality between distal femoral and hip fractures. Distal femoral fractures occur in a complex group of patients that is similar to hip fractures. They have high mortality and complication rates.

Re-fractures after periprosthetic femoral fracture: A difficult to treat growing evidence.

INTRODUCTION: Periprosthetic fractures are increasing. The treatment is mostly surgical, but it has a high complication rate. Re-fracture and non-union with implant failure are the more frequent complications. Those complications are difficult to treat and can lead to severe disability. The purpose of this study is to determine the clinical results of periprosthetic femoral re-fracture treatment. MATERIALS AND METHODS: Twenty patients were treated for femoral re-fractures (17 women, 3 men). The mean age and follow-up are 75.7 years (46-95) and 6.15 years (0.4-15) respectively. The diagnosis of new periprosthetic fracture according to Vancouver classification were: 3 type A, 5 type B1, 1 type B2, 2 B3, 8 type C; 1 Lewis-Rorabeck type II. Patients were followed-up clinically, with a Harris Hip Score, and radiologically at 2, 4, 6, 12 months, and then annually. RESULTS: All patients healed except for two cases in which an infection occurred. Two cases, treated with plate osteosynthesis, had a malunion in varus. Six patients died for unrelated reasons after fracture healing. One patient was excluded because of a follow-up shorter than 12 months. In 16 cases (84%) a Trendelenburg gait or the use of aids for walking has been necessary. At final follow-up the mean HHS was 65 (range 45-82). Fractures treatment differed depending on the type of the fracture, prosthesis stability and bone loss. Tension band wiring, long plate fixation, revision with a long stem with cables or a sandwich technique (two plates or one plate plus one strut graft) have been performed according to fracture type. CONCLUSIONS: Re-fractures and non-union with implant failure are common after periprosthetic fracture treatment. Infection and malunion are the main complications of their treatment. Residual limping with the necessity of aids even after fracture healing is often present. The choice of a correct surgical strategy is essential to minimize the risk of new complications and ensure the highest possibility to heal. The most important factor is to achieve a good stability, a reasonable vital environment and don't leave new areas of lower resistance uncovered. Poor functional outcome has to be expected especially in refracture after a revision surgery.

Periprosthetic acetabular fractures: A New classification proposal.

INTRODUCTION: Acetabulum periprosthetic fractures are rare, but are increasing, due to increase in high-energy trauma and a decrease in mortality index. Reconstruction of an acetabular fracture, in the presence of hip arthroplasty can be very complex and represents a real challenge for orthopedic surgeon. Aim of this multicentric study is to classify periprosthetic acetabulum fractures and to propose a treatment algorithm. MATERIALS AND METHODS: 24 cases of acetabular periprosthetic fracture were treated surgically from 01.01.2010 to 31.04.2017 in three different hospitals; 4 males and 20 females, average age 76 years (range 56-90 years). TREATMENT: 4 cases treated conservatively, 8 cases ORIF, 2 cases treated with acetabular ring and screws, 9 cases ORIF and acetabular cup revision, 1 implant removal without revision. RESULTS: All cases were reviewed at minimum 12 months follow-up. In 22 cases, there was no need for new surgical procedures and radiographically all implants appeared stable and with good bone integration. In a case of a type 1b fracture, a dislocation of prosthetic implant was observed after 3 months. In a case prosthesis was explanted and it was not possible to perform a revision. DISCUSSION AND CONCLUSIONS: Fracture classification systems must facilitate communication between surgeons and encourage documentation and research. However, they should also have prognostic value, so from them should come directly a treatment algorithm. In our experience, most important factors as prognostic and therapeutic predictors were: implant stability and timing of fracture: intraoperative or postoperative. In postoperative fractures CT is mandatory to evaluate cup mobilization and fracture patterns. Our classification proposal is simple and easy to remember for daily use. From it is derived a simple treatment plan.

Risk analysis of patients with an osteolytic acetabular defect after total hip arthroplasty using subject-specific finite-element modelling.

AIMS: Osteolysis, secondary to local and systemic physiological effects, is a major challenge in total hip arthroplasty (THA). While osteolytic defects are commonly observed in long-term follow-up, how such lesions alter the distribution of stress is unclear. The aim of this study was to quantitatively describe the biomechanical implication of such lesions by performing subject-specific finite-element (FE) analysis on patients with osteolysis after THA. PATIENTS AND METHODS: A total of 22 hemipelvis FE models were constructed in order to assess the transfer of load in 11 patients with osteolysis around the acetabular component of a THA during slow walking and a fall onto the side. There were nine men and two women. Their mean age was 69 years (55 to 81) at final follow-up. Changes in peak stress values and loads to fracture in the presence of the osteolytic defects were measured. RESULTS: The von Mises stresses were increased in models of those with and those without defects for both loading scenarios. Although some regions showed increases in stress values of up to 100%, there was only a moderate 11.2% increase in von Mises stress in the series as a whole. The site of fracture changed in some models with lowering of the load to fracture by 500 N. The most common site of fracture was the pubic ramus. This was more frequent in models with larger defects. CONCLUSION: We conclude that cancellous defects cause increases in stress within cortical structures. However, these are likely to lead to a modest decrease in the load to fracture if the defect is large (> 20cm3) or if the patient is small with thin cortical structures and low bone mineral density. Cite this article: Bone Joint J 2018;100-B:1455-62.

Periprosthetic femoral nonunions treated with internal fixation and bone grafting.

INTRODUCTION: Periprosthetic femoral nonunions (PPFN) have a reported incidence of 3-9%. Literature on PPFN management is scarce. The study aim was to review combined results of two academic teaching hospitals using comparable PPFN treatment strategies. MATERIALS AND METHODS: A retrospective review was conducted of all patients treated for a PPFN between February 2005 and December 2016. All patients treated with internal fixation for a PPFN with complete clinical and radiological follow-up until healing were included. Nineteen patients were identified (mean age 71.2 years, range 49-87). Treatment consisted of failed hardware removal, debridement, reduction, and rigid internal fixation with or without bone graft. For revision PPFN surgery, use of dual-plating and bone graft augmentation was common. RESULTS: Eighteen of 19 patients (94.7%) progressed to osseous union. One patient was converted to a total femoral prosthesis. No patients were lost to follow-up. All were ambulatory at last follow-up and mean follow-up was 39.8 months. Fourteen patients (73.7%) united after our index nonunion surgery at mean 9.8 months. Five patients (26.3%) required revision surgery after our index nonunion treatment and in 4 of these cases union was achieved at mean 18.0 months. CONCLUSIONS: Our results suggest debridement, revision of fixation and liberal use of bone grafting can lead to reliable healing in the majority of PPFNs. For those PPFNs that do not heal following initial treatment, good healing potential persists with an additional procedure. LEVEL OF EVIDENCE: Prognostic Level III.

Frequency and associated factor of atypical periprosthetic femoral fracture after hip arthroplasty.

BACKGROUND: Atypical femoral fracture (AFF) is a serious complication after the use of bisphosphonates, and periprosthetic femoral fracture (PFF) appeared as a common complication after hip arthroplasty, especially in senile patients. Although American Society for Bone and Mineral Research has excluded PFFs from the definition of AFFs, several case reports found PFF patients undergoing bisphosphonate treatment, have fractures resembling AFF and the authors suggested that AFF can also occur in operated femurs after hip arthroplasty. To date, the frequency and risk factors of atypical PFF are unknown. The purpose of our study was (1) to evaluate the proportion of atypical PFF among Vancouver type B PFFs, and (2) to determine the association between occurrence of atypical PFF and use of bisphosphonate. METHODS: We reviewed medical records and radiographs of 67 Vancouver type B PFFs (67 patients) due to low-energy trauma and classified them into atypical PFF group and ordinary PFF group. We calculated the proportion of atypical PFFs among PFFs and identified risk factors for atypical PFF. RESULTS: Among the 67 PFFs, 7 fractures (10.4%) were classified as atypical PFF. Longer duration of bisphosphonate use was an independent risk factor of atypical PFF. (Odds ratio 2.600, 95% CI 1.184-5.709, p = 0.017). CONCLUSION: In accordance with wide use of bisphosphonate, atypical PFFs after hip arthroplasty are not rare anymore. Physicians should suspect the atypical PFF, when they meet low-energy fracture in bisphosphonate users, and radiographs show features of AFF.

Failed osteosynthesis of cemented B1 periprosthetic fractures.

BACKGROUND: Periprosthetic fractures about the hip are increasingly common. The literature estimates a failure rate of approximately 10% in Vancouver B1 type fractures which have undergone fixation. There is currently no guidance available on the next step of management for this patient group. This study presents a series of nine Vancouver B1 fractures with failed osteosynthesis and proposes that repeated fixation has poorer results than revision. METHODS: A total of nine patients (five women, four men) with a mean age of 71.2 years (52-83) underwent operative treatment for failed osteosynthesis of periprosthetic fractures of Vancouver type B1. Three patients were revised to a long revision stem while six patients had repeated osteosythesis. Failure was defined as the need for further operative intervention. RESULTS: The three patients revised to a long revision stem at first failure of osteosynthesis required no further surgical intervention. All six patients who had repeat osteoynthesis failed again. Five patients were subsequently successfully treated with revision of the primary stem, three were revised to a long revision stem while two patients required proximal femoral replacement. One patient died prior to revision. The mean follow up following initial B1 fracture was 49.3 months and following definitive operative intervention was 37.7 months. Six patients had died at 1st July 2017. CONCLUSION: Failed osteosynthesis of B1 fractures may necessitate revision rather than repeat fixation, regardless of how well fixed the stem appears. Revision to a long stem provided good results in this cohort.

Problems in plating periprosthetic femur fractures.

Periprosthetic fractures are typically defined as fractures occurring adjacent to a total joint arthroplasty. However, fractures may occur adjacent to a previous internal fixation device used to treat a prior fracture in the same patient, or between implants (the interprosthetic fracture). All of these injuries tend to occur in frail patients with severe osteopenia, and therefore are very challenging to treat. This article provides a brief but thorough review of the current state of the art regarding the treatment of these challenging problems.