Treatment of supracondylar femoral fractures with a retrograde intramedullary nail

Radiographic Union Assessment in Surgically Treated Distal Femur Fractures: A Systematic Review

BACKGROUND

Distal femur fractures are known to have challenging nonunion rates. Despite various available treatment methods aimed to improve union, optimal interventions are yet to be determined. Importantly, there remains no standard agreement on what defines radiographic union. Although various proposed criteria of defining radiographic union exist in the literature, there is no clear consensus on which criteria provide the most precise measurement. The use of inconsistent measures of fracture healing between studies can be problematic and limits their generalizability. Therefore, this systematic review aims to identify how fracture union is defined based on radiographic parameters for surgically treated distal femur fractures in current literature.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Medline, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection databases were searched from inception to October 2022. Studies that addressed surgically treated distal femur fractures with reported radiographic union assessment were included. Outcomes extracted included radiographic definition of union; any testing of validity, reliability, or responsiveness; reported union rate; reported time to fracture union; and any functional outcomes correlated with radiographic union.

RESULTS

Sixty articles with 3,050 operatively treated distal femur fractures were included. Operative interventions included lateral locked plate (42 studies), intramedullary nail (15 studies), dynamic condylar screw or blade plate (7 studies), dual plate or plate and nail construct (5 studies), distal anterior-posterior/posterior-anterior screws (1 study), and external fixation with a circular frame (1 study). The range of mean follow-up time reported was 4.3 to 44 months. The most common definitions of fracture union included "bridging or callus formation across 3 of 4 cortices" in 26 (43%) studies, "bony bridging of cortices" in 21 (35%) studies, and "complete bridging of cortices" in 9 (15%) studies. Two studies included additional assessment of radiographic union using the Radiographic Union Scale in Tibial fracture (RUST) or modified Radiographic Union Scale in Tibial fracture (mRUST) scores. One study included description of validity, and the other study included reliability testing. The reported mean union rate of distal femur fractures was 89% (range 58%-100%). The mean time to fracture union was documented in 49 studies and found to be 18 weeks (range 12-36 weeks) in 2,441 cases. No studies reported correlations between functional outcomes and radiographic parameters.

CONCLUSION

The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. To advance surgical optimization, it is necessary that future research uses validated, reliable, and continuous measures of radiographic bone healing and correlation with functional outcomes.

LEVEL OF EVIDENCE

Level IV. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical comparison of distal femoral fracture fixation: Polyaxial vs. uniaxial locking screws with different blocking screw configurations in retrograde femoral nailing

INTRODUCTION

Clinical studies have indicated reduced reliance on blocking screws with the introduction of polyaxial locking nails, yet the biomechanical superiority of polyaxial locking over blocking screws remains unverified, specifically for distal dia-metaphyseal femur fractures.

HYPOTHESIS

We hypothesized that the combination of multiaxial locking using three screws and parallel locking reinforced by two blocking screws would result in superior outcomes compared to utilizing only parallel locking with two screws and one blocking screw.

MATERIALS AND METHODS

Third-generation custom-made femur models representing AO/OTA 32 A1.2 dia-metaphyseal comminuted oblique fractures were divided into four groups (n=10/group). Group A employed distal fixation with three 4.5-mm polyaxial screws. Group B used two parallel locking screws and two blocking screws, Group C used two parallel locking screws and one blocking screw, and Group D used only two parallel screws. Specimens underwent axial and torsional load testing to assess fatigue strength, ultimate strength, axial stiffness (N/mm), torsional stiffness (N/mm/deg), axial load to failure (N), torsional load to failure (N/mm), coronal and sagittal angulations, and fracture site collapse.

RESULTS

Group C exhibited statistically superior torsional stiffness compared to Groups B and D (p=0.039 and p=0.034, respectively). Axial load to failure was highest in Group B and lowest in Group D (p=0.032). Group C demonstrated the highest torsional strength, while Group B exhibited the lowest (p=0.006). Coronal displacement was greatest in Group B, while Group A showed the highest resistance (p=0.009). Group A demonstrated the greatest resistance to fracture site collapse, with the weakest specimens observed in Groups B and C (p=0.01).

DISCUSSION

The performance of a single laterally positioned blocking screw is comparable to using two blocking screws. Medial positioning of a second blocking screw is unnecessary for stability enhancement. Multiaxial locking prevents fracture site collapse and coronal plane angulation more effectively than other methods. Multiaxial locking and/or parallel screws with a single laterally positioned blocking screw provide superior stiffness and stability for treating unstable dia-metaphyseal distal femoral fractures.

LEVEL OF EVIDENCE

N/A.

Retrograde intramedullary nailing of the femur: identifying the true anatomic axis for the ideal start point

PURPOSE

Retrograde femoral intramedullary nailing (IMN) is commonly used to treat distal femur fractures. There is variability in the literature regarding the ideal starting point for retrograde femoral IMN in the coronal plane. The objective of this study was to identify the ideal starting point, based on radiographs, relative to the intercondylar notch in the placement of a retrograde femoral IMN.

METHODS

A consecutive series of 48 patients with anteroposterior long-leg radiographs prior to elective knee arthroplasty from 2017 to 2021 were used to determine the femoral anatomic axis. The anatomic center of the isthmus was identified and marked. Another point 3 cm distal from the isthmus was marked in the center of the femoral canal. A line was drawn connecting the points and extended longitudinally through the distal femur. The distance from the center of the intercondylar notch to the point where the anatomic axis of the femur intersected the distal femur was measured.

RESULTS

On radiographic review, the distance from the intercondylar notch to where the femoral anatomic axis intersects the distal femur was normally distributed with an average distance of 4.1 mm (SD, 1.7 mm) medial to the intercondylar notch.

CONCLUSION

The ideal start point, based on radiographs, for retrograde femoral intramedullary nailing is approximately 4.1 mm medial to the intercondylar notch. Medialization of the starting point for retrograde intramedullary nailing in the coronal plane aligns with the anatomic axis. These results support the integration of templating into preoperative planning prior to retrograde IMN of the femur, with the knowledge that, on average, the ideal start point will be slightly medial. Further investigation via anatomic studies is required to determine whether a medial start point is safe and efficacious in patients with distal femur fractures treated with retrograde IMNs.

Which fixation produces the best outcome for distal femoral fractures? Meta-analysis and systematic review of retrograde nailing versus distal femoral plating in 2432 patients and 33 studies

PURPOSE

The distal femur comprises a wide intramedullary cavity and thin cortical bone. Firm internal fixation of comminuted fractures with displacement is challenging. Although many comparative studies have reported retrograde intramedullary nailing (RIN) and distal femoral plating (DFP) as the usual fixation methods for distal femoral fractures, no clear conclusion has been reached. Therefore, a meta-analysis and systematic review of the clinical and radiological results were conducted to determine the appropriate treatment method for distal femoral fractures.

METHODS

A systematic search of the PubMed, Embase, Scopus, and Cochrane Library databases from their inception to December 19, 2022, was performed using predefined criteria. Studies comparing the effects of RIN and DFP were considered. The analyzed outcome measures included duration of surgery, blood loss, time to union, delayed union, nonunion, malalignment, implant failure, infection, reoperation, limb length discrepancy, range of motion, persistent anterior knee pain, knee stiffness, and functional scores. Meta-analysis of pooled data was conducted using a random-effects model to determine the standard mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Thirty-three studies with 2,432 patients were included. Compared to DFP, RIN was associated with a shorter time to fracture union (SMD, 1.83 months; 95% CI - 2.76 to - 0.90; P < 0.001) and a lower incidence of postoperative infection (OR 0.54; 95% CI 0.31-0.94; P = 0.03). Pooled analysis revealed no significant differences in other outcome measures between the two treatment modalities.

CONCLUSION

In distal femoral fractures, RIN had a shorter bone union time and was more resistant to infection than DFP. However, there were no significant differences in the other clinical parameters. Therefore, the characteristics, strengths, and weaknesses of RIN and DFP should be carefully identified, and appropriate treatment should be provided based on the patient's medical condition and fracture pattern.

[Translated article] Comparative clinical and biomechanical study of different types of osteosynthesis in the treatment of distal femur fractures

INTRODUCTION AND OBJECTIVES

Distal femoral fractures represent a problem due to their high number of complications. The aim was to compare the results, complications and stability achieved with retrograde intramedullary nailing and the angular stable plate in the treatment of distal femoral diaphyseal fractures.

MATERIAL AND METHOD

A clinical and experimental biomechanical study was carried out using finite elements. The results of the simulations allowed us to obtain the main results related to the stability of osteosynthesis. For clinical follow-up data, frequencies were used for qualitative variables, and Fisher's exact test and χ2 test were used to evaluate the significance of the different factors, with the condition of P<.05.

RESULTS

In the biomechanical study, the retrograde intramedullar nails demonstrated superiority, obtaining lower values in terms of global displacement, maximum tension, torsion resistance, and bending resistance. In the clinical study, the rate of consolidation of the plates was lower than nails (77% vs. 96%, P=.02). The factor that most influenced the healing of fractures treated with plate were the central cortical thickness (P=.019). The factor that most influenced the healing of nail-treated fractures was the difference between the diameter of the medullary canal and the nail.

CONCLUSIONS

Our biomechanical study shows that both osteosynthesis provide sufficient stability, but biomechanically behaves differently. Nails provide greater overall stability being preferable the use of long nails adjusted to the diameter of the canal. Plates form less rigid osteosynthesis, with little resistance to bending.

Comparative clinical and biomechanical study of different types of osteosynthesis in the treatment of distal femur fractures

INTRODUCTION AND OBJECTIVES

Distal femoral fractures represent a problem due to their high number of complications. The aim was to compare the results, complications and stability achieved with retrograde intramedullary nailing and the angular stable plate in the treatment of distal femoral diaphyseal fractures.

MATERIAL AND METHOD

A clinical and experimental biomechanical study was carried out using finite elements. The results of the simulations allowed us to obtain the main results related to the stability of osteosynthesis. For clinical follow-up data, frequencies were used for qualitative variables, and Fisher's exact test and χ2 test were used to evaluate the significance of the different factors, with the condition of P<.05.

RESULTS

In the biomechanical study, the retrograde intramedullar nails demonstrated superiority, obtaining lower values in terms of global displacement, maximum tension, torsion resistance, and bending resistance. In the clinical study, the rate of consolidation of the plates was lower than nails (77% vs. 96%, P=.02). The factor that most influenced the healing of fractures treated with plate were the central cortical thickness (P=.019). The factor that most influenced the healing of nail-treated fractures was the difference between the diameter of the medullary canal and the nail.

CONCLUSIONS

Our biomechanical study shows that both osteosynthesis provide sufficient stability, but biomechanically behaves differently. Nails provide greater overall stability being preferable the use of long nails adjusted to the diameter of the canal. Plates form less rigid osteosynthesis, with little resistance to bending.

Locked Lateral Plating Versus Retrograde Nailing for Distal Femur Fractures: A Multicenter Randomized Trial

OBJECTIVES

The 2 main forms of treatment for distal femur fractures are locked lateral plating and retrograde nailing. The goal of this trial was to determine whether there are significant differences in outcomes between these forms of treatment.

DESIGN

Multicenter randomized controlled trial.

SETTING

Twenty academic trauma centers.

PATIENTS/PARTICIPANTS

One hundred sixty patients with distal femur fractures were enrolled. One hundred twenty-six patients were followed 12 months. Patients were randomized to plating in 62 cases and intramedullary nailing in 64 cases.

INTERVENTION

Lateral locked plating or retrograde intramedullary nailing.

MAIN OUTCOME MEASUREMENTS

Functional scoring including Short Musculoskeletal Functional Assessment, bother index, EQ Health, and EQ Index. Secondary measures included alignment, operative time, range of motion, union rate, walking ability, ability to manage stairs, and number and type of adverse events.

RESULTS

Functional testing showed no difference between the groups. Both groups were still significantly affected by their fracture 12 months after injury. There was more coronal plane valgus in the plating group, which approached statistical significance. Range of motion, walking ability, and ability to manage stairs were similar between the groups. Rate and type of adverse events were not statistically different between the groups.

CONCLUSIONS

Both lateral locked plating and retrograde intramedullary nailing are reasonable surgical options for these fractures. Patients continue to improve over the course of the year after injury but remain impaired 1 year postoperatively.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Distal Femur Replacement Versus Surgical Fixation for the Treatment of Geriatric Distal Femur Fractures: A Systematic Review

OBJECTIVES

The management of geriatric distal femur fractures is controversial, and both primary distal femur replacement (DFR) and surgical fixation (SF) are viable treatment options. The purpose of this study was to compare patient outcomes after these treatment strategies.

DATA SOURCES

PubMed, Embase, and Cochrane databases were searched for English language articles up to April 24, 2020, identifying 2129 papers.

STUDY SELECTION

Studies evaluating complications in elderly patients treated for distal femur fractures with either immediate DFR or SF were included. Studies with mean patient age <55 years, nontraumatic indications for DFR, or SF with nonlocking plates were excluded.

DATA EXTRACTION

Two studies provided Level II or III evidence, whereas the remaining 28 studies provided Level IV evidence. Studies were formally evaluated for methodological quality using established criteria. Treatment failure between groups was compared using an incidence rate ratio.

DATA SYNTHESIS

Treatment failure was defined for both SF and arthroplasty as complications requiring a major reoperation for reasons such as mechanical failure, nonunion, deep infection, aseptic loosening, or extensor mechanism disruption. There were no significant differences in complication rates or knee range of motion between SF and DFR.

CONCLUSIONS

SF and DFR for the treatment of geriatric distal femur fractures demonstrate similar overall complication rates. Given the available evidence, no strong conclusions on the comparative effectiveness between the 2 treatments can be definitively made. More rigorous prospective research comparing SF vs. DFR to treat acute geriatric distal femur fractures is warranted.

LEVEL OF EVIDENCE

Therapeutic Level IV. See instructions for authors for a complete description of levels of evidence.

Extension malunion of the femoral component after retrograde nailing: no sequelae at 6 years

OBJECTIVES

Supracondylar femoral fracture is a complex complication after total knee arthroplasty (TKA). One potential complication of retrograde locked nailing is malunion in extension of the femoral prosthetic component--produced by an overly posterior nail entry point in the intercondylar notch. The aim of this study was to determine the repercussion of this deformity on the midterm radiological and functional outcomes of TKA.

DESIGN

Retrospective review.

METHODS

From 2001 to 2006, 30 patients were treated for supracondylar femoral fracture above TKA with a retrograde locked nail. In 7 patients (6 women and 1 man) with a mean age of 78.8 years (range, 74-84 years), more than 10 degrees of hyperextension (mean of 18.5 degrees) of the femoral component on the sagittal plane was observed without any significant misalignment on the coronal plane. Functional outcomes were assessed using the Knee Society Score.

RESULTS

After a mean follow-up of 68.5 months (range, 48-111 months), all patients' fractures with a hyperextension of the femoral component had consolidated with no clinical or radiological signs of TKA loosening. These patients presented "good" functional outcomes at final follow-up.

CONCLUSIONS

These results should be interpreted with caution. However, isolated hyperextension of the femoral component of a TKA after placing a retrograde nail for a periprosthetic fracture does not seem to significantly affect the functional or radiological outcomes at ∼6-years follow-up.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal femoral fixation: a biomechanical comparison of retrograde nail, retrograde intramedullary nail, and prototype locking retrograde nail

BACKGROUND

Distal femur fractures continue to be a complex surgical problem for which the incidence is increasing. Presently, there is a need for different constructs to address these complex fractures. This study attempts to define the biomechanical properties of several implants.

METHODS

A novel, prototype locking retrograde intramedullary nail and the Russell-Taylor femoral retrograde nail were tested at non-destructive, physiological, axial mode load strength using a young, synthetic bone model for a medial segmental shaft defect in the supracondylar region of the distal femur (medial gap of 10mm, 65mm proximal to the distal joint and parallel to the knee axis). Each specimen was compressively loaded and unloaded to the peak load for 80,000cycles at a 0.5Hz frequency. These were compared to the results from the same lab of the retrograde Trigen intramedullary nail. Motion and peak displacement were measured across the fracture site as a reflection of construct stability.

FINDINGS

Previous testing demonstrated that Trigen intramedullary nail had significantly less motion across the gap and increased overall stiffness of the construct (P<0.05) compared to both Russell-Taylor and prototype nails.

INTERPRETATION

Locking technology used in a nail biomechanically appears to lead to more micro-motion across the fracture gap and to less stiffness in this construct. Further research needs to be invested into intramedullary, locking technology before introducing it into clinical practice.

Do locked compression intramedullary nails improve the biomechanical stability of distal femoral fractures?

BACKGROUND

A distal femur nail with fixed-angle locking screws intends to combine the advantages of angular stability and intramedullary stabilization in extraarticular distal femur fractures. The goal of this study was to analyze whether the locked compression distal femur nail (LCN) was biomechanically more stable than a conventional standard distal femur nail (CN).

METHODS

Both nails were compared on a series of 10 matched pairs of human femora. After setting a distal femur defect fracture, the intramedullary stabilized femur was axially loaded starting from 100 N, increasing in steps of 100 N after every 200 cycles with a triangular frequency of 1 Hz, until a predefined point of failure was reached.

RESULTS

The two types of nails showed no significant difference in terms of maximum tolerated load, maximum number of cycles repeated, or axial deformation of the bone-implant construct. The mean load at failure was 2,954 N for the CN and 2,483 N for the LCN. The mean axial deformation for the conventional (14.8 mm) and locked compression nail (15.3 mm) did not differ significantly. Mode of failure was a bony fracture in all specimens predominantly involving the proximal femur.

CONCLUSIONS

No significant difference in stability between the two compared implants could be demonstrated. The LCN showed comparable characteristics under cyclic axial loading as the conventional distal femur nail. No migration into the articular space or implant failure was observed.

No evidence of infection after retrograde nailing of supracondylar femur fracture in gunshot wounds

BACKGROUND

The aim of the study was to determine whether osteomyelitis of the femur or septic arthritis of the knee develops after retrograde intramedullary nailing of the femur performed within 7 days of supracondylar femur fracture, secondary to gunshot wounds, without skin defects.

METHODS

Fifteen patients with a mean age of 27.8 years (range, 18-52 years), with supracondylar fractures of the femur due to gunshot wounds and without skin defects. Retrograde intramedullary nails were inserted through the intercondylar notch of the femur. We evaluated whether osteomyelitis of the femur or ipsilateral septic arthritis of the knee joint developed postoperatively.

RESULTS

None of the patients who were followed up for a mean period of 11.7 months (range, 9-16 months) showed evidence of ipsilateral septic arthritis of the knee or osteomyelitis of the femur.

CONCLUSION

Retrograde intramedullary nailing of the femur can be performed in patients with supracondylar fractures of the femur due to gunshot wounds, and without skin defects, in the first 7 days after the trauma. Neither osteomyelitis of the femur nor septic arthritis of the knee develops in these patients.

Fixation of distal femoral fractures with the Less Invasive Stabilization System: a minimally invasive treatment with locked fixed-angle screws

BACKGROUND

The Less Invasive Stabilization System (LISS) is an internal fixator, which combines closed reduction of the diaphysis or metaphysis of distal femur fractures with locked unicortical screw fixation.

METHODS

In a retrospective consecutive study, 50 patients with Association for the Study of the Problems of Internal Fixation/Orthopaedic Trauma Association (AO/OTA) type 33-A1 to 33-C3 fractures were treated with the LISS between January 1999 and December 2003. Final results were assessed using the functional score of Neer after a median follow-up of 29 months (15-48 months).

RESULTS

Fifteen male and 16 female patients were followed up. The mean age was 49 years (17-90 years). Deep wound infection was seen in one patient (3%) and malpositioning with cutting-out of the proximal screws was in two patients (6%). All other fractures healed uneventfully without bone graft requirements after a mean of 12 weeks (7-20 weeks). A revised osteosynthesis was performed for correction of a valgus deformity of 20 degrees after 4 months. There was no difference in leg length exceeding 2 cm. One patient had a valgus deformity of 10 degrees combined with a rotational deformity of 10 degrees. Range of motion of the knee joint was >120 degrees in 15 patients (48%); 12 (39%) had a range of motion between 90 degrees and 120 degrees and 4 (13%) between 70 degrees and 90 degrees. The function according to the Neer score was excellent in 15 (48%), good in 10 patients (32%), and fair in 6 patients (20%). The mean Neer score was 80 (60-100).

CONCLUSIONS

The LISS promotes early mobilization and rapid rates of bony and clinical healing without bone grafting with low rates of infection.

Biomechanical analysis of retrograde intramedullary nail fixation in distal femoral fractures

This study employed both mechanical testing and finite element analysis to compare the stiffness variations among different intramedullary nail constructs used in the treatment of distal femoral fractures. Compressive and torsional experiments were conducted on a transversely, as well as an obliquely fractured sawbone femur restored with the retrograde intramedullary nail. Corresponding finite element models were established to evaluate the stress distributions around screw holes. The results showed that a perifracture screw could increase stiffness by 40% for the obliquely fractured femur, but that it played an insignificant role in stiffness improvement for the transverse fracture groups. Moreover, compared to proximal-screw fixation, distal-screw fixation could improve construct stiffness by 20%. The absence of one of the two distal screws would increase the screw-hole stress by 70%. Therefore, the distal screw around the metaphyseal region has a more important stabilizing effect in the femur-nail construct than does the proximal screw. A twisting stress pattern occurs on the unused screw holes of the metaphyseal region and induces a higher risk for fatigue fracture. The locking screw at the fracture site would be most effective only if it passed through the fracture gap to integrate the separated femoral pieces.

A case report of a severe musculoskeletal injury in a wheelchair user caused by an incorrect wheelchair ramp design

The Americans with Disabilities Act (ADA) gives all Americans with disabilities a chance to achieve the same quality of life that individuals without disabilities enjoy. In this case report, we will be discussing the consequences of having inaccessible ramps to persons with disabilities that can result in severe musculoskeletal injuries in a wheelchair user. While going down an inaccessible ramp in the garage of a hospital, a wheelchair tipped over, causing a fracture to the user's right femur. The injured patient was taken to the Emergency Department, where the diagnosis of a fracture of the right femur was made. The fracture then had to be repaired with an intramedullary rod under general anesthesia in the hospital. It was discovered that the ramps in the hospital garage did not comply with the guidelines of the ADA. The wheelchair ramps had a ramp run with a rise > 6 inches (150 mm) and a horizontal projection > 72 inches (1830 mm). This led to the redesign and construction of safe ramps for individuals using wheelchairs as well as for pedestrians using canes, within 1 month after the patient's injury, making it safe for wheelchair users as well as pedestrians using the parking facilities. The ADA specifies guidelines for safe ramps for patients with disabilities. It is important to ensure that hospital ramps comply with these guidelines.

Retrograde nailing versus fixed-angle blade plating for supracondylar femoral fractures: a randomized controlled trial

BACKGROUND

A variety of devices have been used in the treatment of supracondylar femoral fractures. The condylar blade plate relies on the principles of open reduction, absolute stability and interfragmentary compression to achieve union. The technique of retrograde nailing uses indirect reduction of the metaphyseal fracture component, offering relative stability and a less invasive approach. Randomized comparison of these common methods of fixation has not been reported.

METHODS

Twenty-two patients with 23 supracondylar femur fractures were recruited from two regional trauma centres over a 26-month period and randomized to receive either a retrograde intramedullary nail fixation (IM group, 12 fractures) or a fixed-angle blade plate fixation (BP group, 11 fractures). The groups were followed for 12-36 months. The primary outcome measures were revision surgery and general health.

RESULTS

Three patients in the IM group required revision surgery for the removal of implant components. No reoperations occurred in the BP group. There was a trend towards greater pain in the IM group, although there was no statistically significant difference in the scores for any of the SF-36 domains.

CONCLUSION

Both distal femoral nailing and blade plating give good outcomes. There is a trend for patients undergoing retrograde nailing to complain of more pain and to require revision surgery for removal of implants.

The retrograde nail for distal femoral fractures in the elderly: high failure rate of the condyle screw and nut

Displaced distal femoral fractures in elderly patients benefit from surgical fixation. We describe the use of a retrograde femoral nail to treat these fractures. The implant has a special condyle screw and nut that allows for manual compression of the fracture when there is an additional inter-condylar split. We present our results when using this implant to treat 16 patients over a 13-month period. The mean patient age was 78 years (range, 65-96 years). All 16 patients were available at the time of final follow up and proceeded to union at an average time of 11 weeks (range, 10-14 weeks). Twenty-six condyle screw and nuts were used. Ten out of 26 condyle screws in 10 out of 16 patients failed by disengaging at a mean time of 10 weeks (range, 8-12 weeks). Our union rate was unaffected by the nut and bolt disengaging. This would suggest that the condylar compression generated by the nut and bolt may not be critical for union.

Limb Malalignment and Functional Outcome After Antegrade Versus Retrograde Intramedullary Nailing in Distal Femoral Fractures

BACKGROUND

Torsional malalignment and mechanical axis deviation (MAD) are worrisome complications after nailing of distal femoral fractures. Variable, sometimes contradictory, reports about these problems have been published.

METHODS

In a retrospective nonrandomized study, 41 patients (mean age, 44.5 years) with distal third femoral fractures that were operatively treated using either antegrade (20 cases) or retrograde (21 cases) intramedullary nailing during a period of 2 years have been reviewed. Goniometric measurement was done using a navigated ultrasound examination whereas functional evaluation and return to sports were assessed using Merle d'Aubigné functional grading system and Tegner and Lysholm activity score.

RESULTS

There was no difference in femoral length, torsion, or MAD between patients treated using antegrade nails and those treated with a retrograde nail. There was a greater limitation of knee motion with retrograde nailing and of hip motion with antegrade nailing. The functional grading and activity evaluation showed, however, no difference between both groups.

CONCLUSIONS

The study cohort showed that no treatment method had proved an advantage over the other regarding limb geometry or the functional outcome. The proper operative indication, intraoperative control, and the surgeon's experience seem to be more important in this regard than the nailing technique.

Operative treatment of acute distal femur fractures: systematic review of 2 comparative studies and 45 case series (1989 to 2005)

BACKGROUND

The incidence of distal femur fractures is approximately 37 per 100,000 person-years. Typically, distal femur fractures are caused by a high-energy injury mechanism in young men or a low-energy mechanism in elderly women. Managing these fractures can be a challenging task. Most surgeons agree that distal femur fractures need to be treated operatively to achieve optimal patient outcomes. The articular fracture component is usually treated with open reduction and internal lag screw fixation or external tension wire fixation (Illizarov). However, there is no consensus on the type of implant for the fixation of the metaphyseal-diaphyseal fracture component.

OBJECTIVE

The aim of this study is to systematically summarize and compare the results of different fixation techniques (traditional compression plating, antegrade nailing, retrograde nailing, submuscular locked internal fixation, and external fixation) in the operative management of acute nonperiprosthetic distal femur fractures (AO/OTA type 33A and C) and the characteristics of the fractures for each treatment (articular/nonarticular and open/closed). Additionally an attempt was made to evaluate the impact of surgical experience on nonunion rate, fixation failure rate, deep infection rate, and secondary surgical procedure rate. In the context of this article compression plating relates to techniques/implants that require compression of the implant to the femoral shaft-it does not relate to interfragmentary compression.

Arthroscopically-assisted removal of retrograde intramedullary femoral nails

Retrograde nailing of femoral shaft fractures has become more prevalent as a result of its growing acceptance and familiarity to orthopaedic surgeons. Nail removal is occasionally indicated, which may require a formal arthrotomy. We describe an arthroscopic removal technique that has several advantages. The percutaneous technique imparts less morbidity than a more extensive arthrotomy. More importantly, additional intra-articular pathology can be thoroughly assessed and treated, such as meniscal tears and chondral injury, which may have occurred at the time of injury. These are potential causes of knee pain, which usually cannot be properly diagnosed without arthroscopy. Our findings also support the existence of a stable fibrous cap, which forms over the entry portal of a well-seated retrograde femoral nail as well as no evidence of intra-articular metallosis.

The role and efficacy of retrograding nailing for the treatment of diaphyseal and distal femoral fractures: a systematic review of the literature

The aim of this analysis has been to evaluate the efficacy of retrograde nailing in the treatment of distal femur and femoral shaft fractures. Articles were extracted from the Pubmed database and the retrieved reports were included in the study only if pre-specified eligibility criteria were fulfilled. Moreover, a constructed questionnaire was administered, aimed at assessing the quality of the outcomes. Twenty-four articles were eligible for the final analysis, reviewing a total of 914 patients (mean age of 48.8 years) who sustained 963 distal and diaphyseal femoral fractures. The overall mortality rate was 5.3%. The incidence of infection was 1.1% and for septic arthritis of the knee was 0.18%. In patients with distal femoral fractures, the mean time to union and rate to union were 3.4 months and 96.9%, respectively. The mean range of knee motion was 104.6 degrees . The rates of knee pain, malunion and re-operations were 16.5, 5.2 and 17%, respectively. Patients with femoral shaft fractures had a mean time to union 3.2 months, whilst the rate of union was 94.2%. The mean range of knee motion was 127.6 degrees . The rates of knee pain, malunion and re-operations were 24.5, 7.4 and 17.7%, respectively. We concluded that retrograde intramedullary nailing appears to be a reliable treatment option, mainly for distal femoral fractures. However, in the management of diaphyseal fractures, retrograde intramedullary nailing is associated with high rates of knee pain and lower rates of fracture union.

Early patellofemoral osteoarthritis caused by an osteochondral defect after retrograde solid nailing of the femur in sheep

BACKGROUND

Retrograde femoral nailing (RFN) is an increasingly used technique for internal fixation of femoral fractures. Geometrically and empirically, the nail entry zone is close to the center of the femoral groove, causing concern about the development of patellofemoral osteoarthritis.

METHODS

We studied the effect of opening the distal femur through the femoral groove on the development of osteoarthritis in sheep after retrograde reamed insertion of a solid titanium nail into the femoral canal. Knees were radiographically and macroscopically studied for the presence of osteophytes and signs of cartilage degeneration. Controls underwent the same procedure without opening the femoral groove.

RESULTS

The study group showed time-dependent macroscopic and radiographic signs of osteoarthritis with predominant involvement of the patellofemoral joint.

CONCLUSION

RFN can cause patellofemoral osteoarthritis. Care should be exercised to use RFN in isolated supracondylar or shaft fractures of the femur in healthy young adults.

Supracondylar femoral fractures in elderly patients treated with the dynamic condylar screw and the retrograde intramedullary nail: a comparative study of the two methods

INTRODUCTION

The objective of this study is to present the results of surgical management of supracondylar fractures of the femur (types A and C according to the AO/ASIF classification) in elderly patients with the use of two different methods of fixation: the mini open dynamic condylar screw fixation (DCS) and the closed retrograde intramedullary nailing (RIN).

MATERIALS AND METHODS

Eighty patients with supracondylar fractures of the femur were treated from January 1994 to June 2000 and 72 of them followed up completely. There were 25 (34%) men and 47 (65%) women with a median age of 73.2 years (range 60-88 years). In patients with the same type of fracture, the chosen method was random, one after the other (alternately). RIN was used in 35 patients, and DCS was used in 37. The mean operative time for the DCS fixation group was 145 min (range 115-180 min), whereas for the RIN group it was 92 min (range 76-110 min) (p<0.001) with an average estimated blood loss of 310 cc (range 120-450 cc) and 118 cc (range 90-165 cc), respectively (p<0.001). The mean follow-up was 28 months (range 18-42 months).

RESULTS

According to the criteria set by Schatzker and Lambert, excellent results were recorded in 18 (51%), good in 11 (31%), moderate in 3 (9%), poor in 3 (9%) patients with RIN and excellent in 19 (51%), good in 11 (30%), moderate in 4 (11%) and poor in 3 (8%) patients with DCS (p>0.05). The complications that occurred in the RIN group were 2 (6%) stiffness of the knee (mean flexion 80 degrees), 2 (6%) non-unions, 2 (6%) varus deformity and in the DCS group 2 (5%) haematomas, 4 (11%) stiffness of the knee (mean flexion 73 degrees) and 2 (5%) non-unions.

CONCLUSION

Although the two methods appear to have the same percentage of excellent results and same time to bony union, RIN is preferable to DCS in terms of less blood loss and shorter operating time.

Femur-LISS and distal femoral nail for fixation of distal femoral fractures: are there differences in outcome and complications?

We evaluated the functional and radiologic outcomes after stabilization of distal femoral fractures using the distal femoral nail and a less invasive stabilization system to determine if the new implants are superior to other implants (especially the condylar blade plate) regarding the rates of axial deviation, nonunion, and infection and if one of these new implants (Less Invasive Stabilization System, or distal femoral nail) is superior to the other. Two groups, each with 16 patients, were documented prospectively and the results were compared. To record the findings objectively, the Lysholm-Gillquist score was used. A conversion procedure was done in two patients in the plate group and one patient of the nail group. At the 1-year followup mobility of the knee was on average 110 degrees in the plate group and 103 degrees in the nail group. The Lysholm-Gillquist score did not show any significant differences between the groups. There were clinically relevant varus or outer rotation deviations in three patients in the plate group and two patients in the nail group. The two minimally invasive implants used were good in terms of technique and outcome for treatment of distal femoral fractures and did not differ significantly for epidemiology, fracture type, conversion procedures, infection rate, malalignments, and subjective and objective findings at the 1-year followup. They were also superior to the condylar plate in terms of infection and axial malalignments.

Supracondylar nailing for difficult distal femur fractures

PURPOSE

To evaluate outcome following supracondylar nailing for distal femur fractures.

METHODS

The clinical and radiological outcome for 13 patients treated between January 1995 and December 1998 at the University Malaya Medical Center was assessed. Patients were seen for follow-up for a mean duration of 20.2 months.

RESULTS

There were no cases of non-union or infection. Overall assessment of clinical outcome based on the criteria of Schatzker and Lambert was graded excellent in 6 patients, good in 3 patients, fair in 3 patients, and one graded as a failure.

CONCLUSION

Supracondylar nailing for fixation of supracondylar (Arbeitsgemeinschaft für Osteosynthesefragen [AO] type A) and less comminuted intercondylar (AO type C1 and C2) fractures is recommended by the authors.

Retrograde interlocked intramedullary nailing of supracondylar distal femur fractures in an average 76-year-old patient population

Twenty-seven fractures of the distal femur in 27 adult patients were treated with retrograde, interlocked, intramedullary nails after intercondylar fracture extension had been reduced and treated with lag screws. Postoperatively, early mobilization exercises began immediately, but weight bearing was not allowed until clinical union was achieved, after which full weight bearing was permitted. Retrograde, interlocked, intramedullary nailing provides an excellent technique to establish union of supracondylar and distal femoral shaft fractures with a low complication rate and opportunity to regain knee motion in the mentally competent, motivated patient.

Optimal entry point for retrograde femoral nailing

OBJECTIVE

The purpose of this study is to identify the optimum entry point for retrograde femoral nailing, defined as that point which will provide adequate fracture alignment while minimizing soft-tissue and articular cartilage injury.

DESIGN

Cadaveric study.

SETTING

Biomechanics laboratory.

MAIN OUTCOME MEASURE

Anatomic relationships and fracture reduction. METHODS Eleven cadaveric femori with attached knee joints underwent retrograde femoral nailing with a Synthes femoral nail (Synthes, Paoli, PA, U.S.A.). After placement of the nail, the specimens underwent an osteotomy 3 inches proximal to the articular surface. Multiple entry points were tested to determine fracture alignment and extent of articular cartilage injury. Medial-lateral and anterior-posterior displacements, in addition to any soft-tissue or articular surface trauma, were recorded for these various points of entry.

RESULTS

An entry point of 1.2 cm anterior to the femoral origin of the posterior cruciate ligament resulted in the least anterior-posterior displacement of the femoral shaft following fracture. In the coronal plane, an entry point at the midpoint of the intercondylar sulcus was identified as minimizing the displacement following fracture. This ideal position allows for proper seating of the nail within the intercondylar sulcus, resulting in minimal damage to the articular cartilage and posterior cruciate ligament and minimal disruption of the patella femoral joint.

CONCLUSION

Retrograde femoral nailing should be used cautiously in select patients, when conventional antegrade nailing cannot be used, due to the unavoidable injury to the knee articular surface associated with this technique. The optimum entry point of 1.2 cm anterior to the femoral posterior cruciate ligament origin and centered in the intercondylar sulcus provides the optimal balance of fracture reduction and knee joint sparing. It may be difficult to target this site with a percutaneous technique and may require direct visualization of the intercondylar sulcus for ideal nail placement.

Retrograde intramedullary nailing of supracondylar femoral fractures: design and development of a new implant

Since 1992 we have developed an implant in which the distal (condylar) screws have a diagonal configuration so that the screws can be closer to the distal end of the nail, allowing more distal fractures to be fixed. It also utilises the denser bone of the posterior condyles for more secure fixation in osteoporotic patients. The new implant was used for 24 extra-articular fractures from September 1994 to September 1997, and for 14 articular fractures from February 1995 to December 2000. There was no significant difficulty with obtaining fixation in very distal fractures and in osteoporotic bone. Early weightbearing was encouraged in those with extra-articular fractures. All fractures united within 3 months except one which required a bone graft (but no revision of implant) at 6 months. Average knee flexion at final followup was 101 degrees for extra-articular fractures and 106 degrees for articular fractures. Complications included quadriceps adhesions requiring further surgery in two patients who had open fractures, and malunion in one patient who had an early design of the implant and a 4.5mm condylar screw broke. Nine patients required late removal of condylar screws due to local soft tissue irritation.

Oncologic uses of the retrograde femoral nail

Destructive lesions about the distal femur represent difficult treatment situations. Patients who present with impending or pathologic fractures require a method of fixation that provides adequate stabilization to allow for early, pain-free ambulation. Other considerations include restoration of functional range of motion, low perioperative morbidity and mortality risk, and minimal soft tissue dissection. Eleven patients with 12 pathologic or impending fractures of the distal femur who were treated with retrograde intramedullary nailing with and without polymethylmethacrylate augmentation were retrospectively reviewed. Followup averaged 17 months. Postoperative range of motion averaged 94 degrees flexion, 90% of patients reported no or modest pain, 81% were functioning with no restrictions or recreational restrictions only, and all patients were enthusiastic or satisfied with their surgical outcome. There were no perioperative mortalities, but one patient had 2 cm shortening secondary to broken distal locking screws and asymptomatic nail protrusion into the knee. Using the system for functional evaluation of reconstructive treatment of tumors of the musculoskeletal system, the average score for each patient was 25 (range, 18-30) or 83% (60%-100%) of the maximum score. The retrograde nail was an easy and successful method of fixation in this clinical setting.

Mechanical comparison of endosteal substitution and lateral plate fixation in supracondylar fractures of the femur

OBJECTIVE

To assess for improved rigidity with the addition of a medial endosteal plate to laterally plated supracondylar femoral fractures.

DESIGN

A randomized paired study in a supracondylar femoral fracture model comparing two fixation methods tested cyclically in axial and torsional loading.

METHODS

One-centimeter supracondylar gap osteotomies were created in twenty synthetic femurs approximately six centimeters proximal to the knee joint. Ten were stabilized with a lateral eight-hole buttress plate alone, and ten were secured by a similar lateral buttress plate plus a medial endosteal eight-hole dynamic compression plate. Group 1 (n = 5; lateral plate alone) and Group 2 (n = 5; lateral and endosteal plates) were axially loaded up to 700 newtons through a materials test system for three cycles. A displacement transducer detected movement at the medial fracture gap. Group 3 (n = 5; lateral plate alone) and Group 4 (n = 5; lateral and endosteal plates) were tested in torsion. A rod-and-pulley system created an external rotation torque up to twenty Newton-meters for three cycles. A rotary potentiometer measured angular displacement.

RESULTS

Lateral buttress plating with endosteal substitution showed statistically significant decreased motion at the fracture site in torsional (p < 0.004) and axial loading (p < 0.0001) versus lateral buttress plating alone using Student's t test.

CONCLUSION

The addition of a 4.5-millimeter endosteal plate to a lateral buttress plate provides significantly increased stability, as compared with lateral plating alone in a femoral supracondylar fracture model during simulated axial and torsional loading. Neither fixation construct, however, restored the torsional stability of the distal femur to its preinjury (intact) level.

Mechanical comparison of a distal femoral side plate and a retrograde intramedullary nail

OBJECTIVE

To compare quantitatively the axial and torsional stiffness of a retrograde intramedullary nail and a fixed angle screw side plate in treating a supracondylar femur fracture in osteopenic femora. To determine the modes of failure of an intramedullary nail and a side plate under axial loading.

DESIGN

Matched pair cadaveric study.

SETTING

Orthopaedic biomechanics laboratory.

PATIENTS AND OTHER PARTICIPANTS

Eleven matched pairs of preserved human femora were selected. The cadaveric specimens were harvested from relatively elderly donors with an average age of 75.6 years, which represents the principal population at risk for poor fracture fixation.

INTERVENTION

The eleven matched pairs were osteotomized to simulate segmental structural defects in the supracondylar region. One femur of each matched pair was fixed with an intramedullary nail, and the contralateral femur was fixed with a side plate.

MAIN OUTCOME MEASURES

Axial and torsional stiffness values. Axial modes of failure.

RESULTS

The intramedullary nail axial stiffness was 14 percent (p = 0.04) less and torsional stiffness was 17 percent (p = 0.05) less than that provided by the side plate. The axial failure of the intramedullary nail occurred distally, allowing the hardware to protrude into the articular space. The side plate also failed distally by displacing the condylar screw into a varus angulation.

CONCLUSION

The mechanical advantages favor the use of the side plate if fixation stiffness is essential. The axial mode of failure occurs distally for both fixation devices.

The supracondylar intramedullary nail in elderly patients with distal femoral fractures

From February 1994 until July 1997, a prospective study of all elderly patients with a displaced distal femoral fracture, who were treated with an intramedullary supracondylar nail, was made. The outcome of 31 fractures in 30 elderly patients was studied. The average age was 82 years (55-98). Two-thirds of the patients had had previous ipsilateral femoral pathology. Average acute hospital stay was 17 days. All patients were reviewed at 6 months and all cases have been followed for over 1 year. More than 90% of surviving fractures had healed within 6 months of the operation. Outcome scores were; 22 (85%) excellent or satisfactory, 2 (7.5%) unsatisfactory and 2 (7.5%) failures. The mortality rate was 17% at 6 months and 30% at 1 year, which is similar to patients with a fractured neck of femur. This nail is recommended for its versatility and favourable outcome scores in this age group.