Femoral neck fracture after removal of the compression hip screw from healed intertrochanteric fractures

Pediatric fractures following implant removal: A systematic review

OBJECTIVES

To evaluate the available literature for postoperative fracture rates following implant removal in the pediatric population.

METHODS

A systematic review of articles in the PubMed and Embase computerized literature databases from January 2000 to June 2022 was performed using PRISMA guidelines. Randomized controlled trials, case-control studies, cohort studies (retrospective and prospective), and case series involving pediatric patients that included data on fracture rate following removal of orthopedic implants were eligible for review. Two authors independently extracted data from selected studies for predefined data fields for implant type, anatomic location of the implant, indication for implantation, fracture or refracture rate following implant removal, mean time to implant removal, and mean follow-up time.

RESULTS

Fifteen studies were included for qualitative synthesis. Reported fracture rates following implant removal vary based on several factors, with an overall reported incidence of 0%-14.9%. The available literature did not offer sufficient data for conduction of a meta-analysis.

CONCLUSION

Our systematic review demonstrates that fracture following implant removal in pediatric patients is a relatively frequent complication. In children, the forearm and femur are the most commonly reported sites of fracture following removal of implants. Traumatic fractures treated definitively with external fixation have the highest reported aggregate rate of refracture. Knowledge of the incidence of this risk is important for orthopedic surgeons. There remains a need for well-designed studies and trials to further clarify the roles of the variables that contribute to this complication.

Use of calcium phosphate cement after removal of a cephalomedullary nail: A case report

Femoral neck fracture in the absence of trauma is a rare, but known complication after hardware removal. This complication may be due to the boney defect created by the hardware removal itself, or the increase in femoral neck strain that occurs after removal of the hardware. Previous biomechanical studies have suggested that filling the defect with calcium phosphate cement after removal of hardware may prevent the development of a femoral neck fracture. However, there are no reports on the use of calcium phosphate cement after removal of hardware in the clinical setting. The purpose of this case discussion is to present the first reported case, to our knowledge, of the use of calcium phosphate cement augmentation of the boney defect after lag screw removal, and the subsequent failure resulting in atraumatic femoral neck fracture.

Should cannulated screws be removed after a femoral neck fracture has healed, and how? A finite element analysis of the femur before and after cannulated screw removal

PURPOSE

The removal of three inverted triangular parallel cannulated screws after the femoral neck fracture healing is sometimes accompanied by osteonecrosis of the femoral head (ONFH) or its refracture. The purpose of this study was to determine the biomechanical changes of the femur before and after the screw removal using a finite element analysis.

METHODS

The CT data of the femurs were obtained from a 69-year-old healthy female to establish the femur models. The established finite element models consisted of N, C, and R groups: N group, the normal femur; C group (to simulate the femoral neck fracture healing after the internal fixation), the normal femur with three inverted triangular parallel cannulated screws (C1) or with two upper parallel screws (C2). For the R1 or R2 groups, the screws in the model of the C1 or C2 individuals were gradually removed in seven or three types of different screw combinations, respectively. The stresses and displacements of the femur were determined.

RESULTS

(1) Compared with the N group, a uniform stress distribution was stopped by the addition of three screws in the C1 group; in contrast, all screw removals resulted in the stress concentration on the screw holes and the disappearance of stress shielding. Moreover, the average stress of the femoral head in C1 group increased by 37.85%, while that of the femoral neck decreased by 23.03%. (2) Compared with the C1 group, while only the lowest femoral calcar screw was removed, there was a similar stress distribution in the proximal femur, and the average stress of the femoral head increased only by 0.35% although that of the femoral neck increased by 63.62%; however, removal by any other means resulted in a significant stress concentration in the proximal femur and a significant increase in the average stresses of the femoral head and neck (5.96-40.95% and 12.82-75.46%, respectively). (3) Compared with the N or C1 group, there was a significant stress concentration on the screws and its surrounding proximal femur in the C2 group. (4) Compared with the C2 group, the simultaneous removal of two upper screws not only did not cause a significant stress concentration on the proximal femur but also significantly reduced the average stresses of the femoral head and neck by 87.49% and 65.51% respectively. On the contrary, the gradual removal of two screws caused a significant stress concentration on the screw and its surrounding proximal femur although the average stresses of the femoral head and neck decreased by 88.79-89.06% and 67.00-67.22%, respectively. (5) Compared with the N group, the average displacements of the femoral head and neck in the C1 group increased only by 3.12% and 3.37%, respectively. Additionally, compared with the C1 group, while three, two, or one screw was simultaneously removed, the average displacements of the femoral head and neck only fluctuated - 5.51-1.65% and 1.78-9.03%, respectively.

CONCLUSIONS

Residual internal fixation after femoral neck fracture healing may lead to stress concentration on screws and stress shielding around screws. The first removal of the lowest femoral calcar screw and then the second removal of two upper residual screws have a minimum effect on the stress concentration on the proximal femur and the average stress on the femoral head. The incorrect screw removal and resulting femoral load may well be closely related to occurrence in ONFH or its refracture.

Refracture After Removal of the PFNA in a Healed Intertrochanteric Femoral Fracture: Case Report

Hardware removal in a healed intertrochanteric fracture in elderly, which is not a routine procedure, should be needed in the case of irritable hardware. The reports of refracture after hardware removal can be seen as sparse in current literature, which are focused to secondary femoral neck fracture after removal of the lag screw or blade. We experienced a case of the intertrochanteric refracture and varus collapse after the PFNA removal in a healed fracture, treated with valgus trochanteric osteotomy and angled blade plate fixation. The PFNA is an innovative device for the treatment of the trochanteric fracture; however, the complications after removal never end. Therefore, the removal from healed fracture in elderly who have osteoporosis should not be recommended unless intractable pain had persisted.

Treatment of irreducible femoral intertrochanteric fractures using a wire-guided device

PURPOSE

Treatment of irreducible femoral intertrochanteric fractures often requires open reduction. However, the technique unavoidably causes patients to suffer greater trauma. As such, minimally invasive techniques should be employed to reduce the surgical-related trauma on these patients and maintain a stable reduction of the fractures. Herein, a minimally invasive wire introducer was designed and used for the treatment of femoral intertrochanteric fractures. The effectiveness of using a wire-guided device to treat irreducible femoral intertrochanteric fractures was evaluated.

METHODS

Between 2013 and 2018, patients with femoral intertrochanteric fractures who were initially treated by intramedullary nail fixation but had difficult reduction using the traction beds were retrospectively reviewed. Decision for an additional surgery was based on the displacement of the fracture. The patients were then divided into two groups: those in the control group received an open reduction surgery while those in the observation group received a closed reduction surgery using a minimally invasive wire introducer to guide the wire that could assist in fracture reduction. The operation time, blood loss, visual analogue scale scores, angulation, reduction, neck-shaft angle, re-displacement, limb length discrepancy, and union time were then recorded and analyzed to determine the efficiency of the wire introducer technique. Categorical variables were analyzed by using Chi-square test, while continuous variables by independent t-test and the Mann-Whitney test accordingly.

RESULTS

There were 92 patients included in this study: 61 in the control group and 31 in the observation group. There were no significant differences in baseline demographic factors between the two groups. All surgeries were successful with no deaths within the perioperative period. The average follow-up time for the patients was 23.8 months. However, the observation group had a significantly shorter operation time, lower visual analogue scale score, less intraoperative bleeding, and shorter fracture healing time. There were no significant differences in the angulation, reduction, neck-shaft angle, and limb length discrepancy between the two groups.

CONCLUSION

The minimally invasive wire guide achieved a similar effect to that of open reduction in the treatment of intertrochanteric fractures with difficult reduction. Moreover, the minimally invasive wire introducer is a good technology that accurately guides the wire during reduction. Indeed, it is an effective technique and achieves good clinical outcomes in restoration of irreducible femoral intertrochanteric fractures.

Clinical outcomes of PFNA-II in the Asian intertrochanteric fracture patients: Comparison of clinical results according to proximal nail protrusion

PURPOSE

This study intended to explore the clinical outcomes of PFNA-II, one of the commonly used fixation devices for intertrochanteric fractures and the association of clinical results with the extent of proximal nail protrusion.

MATERIALS AND METHODS

Of 315 cases that underwent internal fixation using PFNA-II between September 2010 and June 2018 among intertrochanteric fracture patients aged over 65 years, a total of 86 patients with an ability to communicate clearly and a minimum follow-up of 6 months were retrospectively reviewed. We classified the subjects according to PFNA-II protrusion over the greater trochanter area on anteroposterior radiographs. Differences between the two groups were examined by comparing demographic characteristics including gender, age, height, weight and BMI, instrumental characteristics including PFNA nail size, nail diameter, blade length and blade position, radiologic characteristics including reduction quality, Dorr type and bone union, and clinical characteristics including GT pain,VAS score and Harris Hip Score (HHS).

RESULTS

A total of 86 cases were divided into 30 (34.9%) in the protrusion group (group A) and 56 (65.1%) in the non-protrusion group (group B). No significant difference was found in demographic characteristics such as gender, age, height, weight and BMI between the two groups. Two groups had no statistically significant difference in PFNA nail length, nail diameter and blade length, but showed a statistically significant difference in blade position. At the latest follow-up, the mean HHS shows no statistically significant difference between the two groups. On the contrary, the number of patients complaining of GT pain and VAS score were statistically significantly higher in group A. Removal of metal implants was performed in two patients in the protrusion group due to a complaint of persistent GT pain.

CONCLUSION

Nail protrusion over the greater trochanter area occurs frequently after the surgical treatment of intertrochanteric fracture using PFNA-II. When the nail protruded into the greater trochanter, the number of patients who clinically complained of pain was statistically significantly high. We recommend a modification to the PFNA-II that would further shorten the proximal nail end suitable for the Asian population to achieve better clinical results in the fixation of intertrochanteric fractures.

The Role of Implant Removal in Orthopedic Trauma

Although implant removal is common after orthopedic trauma, indications for removal remain controversial. There are few data in the literature to allow evidence-based decision-making. The risk of complications from implant removal must be weighed against the possible benefits and the likelihood of improving the patient's symptoms.

Femoral neck fractures after removal of hardware in healed trochanteric fractures

INTRODUCTION

Hardware removal in healed trochanteric fractures (TF) in the absence of infection or significant mechanical complications is rarely indicated. However, in patients with persistent pain, prominent material and discomfort in the activities of daily living, the implant is eventually removed. Publications of ipsilateral femoral neck fracture after removal of implants from healed trochanteric fractures (FNFARIHTF) just because of pain or discomfort are rare. The purpose of this systematic review of the literature is to report on the eventual risk factors, the mechanisms, the clinical presentation, and frequency, and to pay special emphasis in their prevention.

MATERIALS AND METHODS

A comprehensive review of the literature was undertaken using the PRISMA guidelines with no language restriction. Case reports of FNFARIHTF and series of TF with cases of FNFARIHTF due to pain or discomfort published between inception of journals to December 2016 were eligible for inclusion. Relevant information was divided in two parts. Part I included the analysis of cases of FNFARIHTF, with the objective of establishing the eventual risk factors, mechanisms and pathoanatomy, clinical presentation and diagnosis, treatment and prevention. Part II analyzed series of TF which included cases of FNFARIHTF for assessing the incidence of femoral neck fractures in this condition.

RESULTS

Overall 24 publications with 45 cases of FNFARIHTF met the inclusion criteria. We found that the only prevalent factors for FNFARIHTF were: 1) preexisisting systemic osteoporosis, as most patients were older and elder females, with lower bone mineral density and bone mass; 2) local osteoporosis as a result of preloading by the fixation device in the femoral neck, leading to stress protection, reducing the strain at the neck, and increasing bone loss and weakness; and 3) the removal of hardware from the femoral neck, with reduction of the failure strength of the neck. The femoral neck fractures were spontaneous, i.e. not related to trauma or fall, in 87.5% of the cases, mostly subcapital, and with no prevalence between displaced and undisplaced fractures. The clinical presentation was that of a spontaneous fracture, and most of the patients consulted because of hip pain and presented in the emergency room walking by themselves which led to delayed diagnosis in several instances. Radiological diagnosis was mostly with radiographs, though in some cases CT scans or MRI were necessary. The overall median incidence of this complication was 14.5% after hardware removal because of pain or discomfort in healed trochanteric fractures.

CONCLUSION

The risk factors for FNFARIHTF seem to be preexisisting systemic osteoporosis, local osteoporosis as a result of preloading by the fixation device in the femoral neck, and the removal of hardware from the femoral neck, with reduction of the strength of the neck. The clinical presentation may be obscure as most of the patients complain of hip pain of some days or weeks, and arrive in the hospital walking. Therefore, the attending physician should be alert in order to request the appropriate radiological investigation and if this is not clear CT scan or MRI should be done in order to diagnose promptly these "spontaneous" fractures. Treatment should be replacement surgery in most cases; however, there is some place for internal fixation especially in undisplaced fractures or younger patients. The occurrence of the femoral neck fracture after hardware removal may be prevented with re-osteosynthesis and the use of bone chips or bone substitutes. Finally, the relatively high incidence of this complication should alert orthopaedic surgeons to reduce the removal of hardware in healed trochanteric fractures to very selected cases.

Increased risk for complications following removal of hardware in patients with liver disease, pilon or pelvic fractures: A regression analysis

PURPOSE

Indications for removing orthopedic hardware on an elective basis varies widely. Although viewed as a relatively benign procedure, there is a lack of data regarding overall complication rates after fracture fixation. The purpose of this study is to determine the overall short-term complication rate for elective removal of orthopedic hardware after fracture fixation and to identify associated risk factors.

MATERIALS AND METHODS

Adult patients indicated for elective hardware removal after fracture fixation between July 2012 and July 2016 were screened for inclusion. Inclusion criteria included patients with hardware related pain and/or impaired cosmesis with complete medical and radiographic records and at least 3-month follow-up. Exclusion criteria were those patients indicated for hardware removal for a diagnosis of malunion, non-union, and/or infection. Data collected included patient age, gender, anatomic location of hardware removed, body mass index, ASA score, and comorbidities. Overall complications, as well as complications requiring revision surgery were recorded. Statistical analysis was performed with SPSS 20.0, and included univariate and multivariate regression analysis.

RESULTS

391 patients (418 procedures) were included for analysis. Overall complication rates were 8.4%, with a 3.6% revision surgery rate. Univariate regression analysis revealed that patients who had liver disease were at significant risk for complication (p=0.001) and revision surgery (p=0.036). Multivariate regression analysis showed that: 1) patients who had liver disease were at significant risk of overall complication (p=0.001) and revision surgery (p=0.039); 2) Removal of hardware following fixation for a pilon had significantly increased risk for complication (p=0.012), but not revision surgery (p=0.43); and 3) Removal of hardware for pelvic fixation had a significantly increased risk for revision surgery (p=0.017).

CONCLUSIONS

Removal of hardware following fracture fixation is not a risk-free procedure. Patients with liver disease are at increased risk for complications, including increased risk for needing revision surgery following hardware removal. Patients having hardware removed following fixation for pilon fractures also are at increased risk for complication, although they may not require a return trip to the operating room. Finally, removal of pelvic hardware is associated with a higher return to the operating room.

Complications following implant removal in patients with proximal femur fractures - an observational study over 16 years

BACKGROUND

Fractures of the proximal femur commonly occur but the majority of orthopaedic surgeons do not consider general hardware removal as a routine necessity. Indications and time interval for hardware removal in this special selected patient group is still controversial. Therefore we performed a retrospective study to address the following questions: 1) Is there a difference between the medically- (infection, mechanical problems, implant failure) and non-medically indicated group (patients demand, meteoro-sensitivity, foreign body sensation) in relation to complications? 2) Is there a correlation regarding time interval between implantation and removal comparing these two groups? 3) Is there a context related refracture rate? 4) Should non-medically indicated implant removal (IR) be performed due to persistent pressure from the patient?

HYPOTHESIS

We hypothesized that non-medically indicated implant removals should be avoided due to a significantly higher number of associated complications.

PATIENTS AND METHODS

A total of 371 consecutive patients with 424 hardware removal procedures following a proximal femur fracture, between 08/1992 and 11/2008, have been included. Study population was divided into two groups according to their indication for implant removal: medically indicated group (MIR) consisted of 299 patients (80.59%) and 72 patients (19.41%) were assigned to the non-medically indicated (NMIR) group.

RESULTS

In the NMIR subgroup a total of (n = 21) 28% complications occurred compared to 11.46% in the MIR subgroup; (P < 0.005), 86.51% of IR in the MIR group were performed within 1.5 years, compared to 79.17% in the NMIR group after 2 to 3.5 years (NS). In the MIR group 1 refracture occurred, compared to 4 in the NMIR group (NS).

CONCLUSION

Non-medically indicated implant removal should be avoided due to the higher complication rate of 28%. Surgeons and patients should be aware of the imminent complications and therefore implant removal should only be performed for good medical reasons.

LEVEL OF EVIDENCE

Level IV. Historical case study.