Scholarly article on topic 'Subtrochanteric femur fracture treated by intramedullary fixation'

Subtrochanteric femur fracture treated by intramedullary fixation Academic research paper on "Clinical medicine"

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Abstract of research paper on Clinical medicine, author of scientific article — Zu-Bin Zhou, Song Chen, You-Shui Gao, Yu-Qiang Sun, Chang-Qing Zhang, et al.

Abstract Purpose To discuss surgical technique, operative efficacy and clinical outcome of intramedullary fixation in the treatment of subtrochanteric femur fractures. Methods From February 2011 to February 2013, 76 cases of subtrochanteric femur fractures were treated by intramedullary fixation in our hospital, including 53 males and 23 females, with the age range of 37–72 years (mean 53.5 years). According to Seinsheimer classification, there were 2 cases of type I, 7 type II, 15 type III, 23 type IV and 29 type V. Firstly, all patients underwent closed reduction with the guidance of C-arm fluoroscopy in a traction table. Two cases of type I and 3 cases of type III fractures had ideal closed reduction followed by internal fixation. The others needed additional limited open reduction. Radiographic examination was used to evaluate callus formation and fracture healing in postoperative 1, 3, 6 and 12 months follow-up. Functional recovery was evaluated by Harris Hip Scoring (HHS) system. Results Patients were followed up for 6–12 months. All fractures were healed except one patient with delayed union. The average bone union time was 4.5 months. According to HHS system, 65 cases were considered as excellent in functional recovery, 8 good, 2 fair and 1 poor. The proportion of the patients with excellent and good recovery was 96.05%. Conclusion Intramedullary fixation is feasible for the treatment of subtrochanteric femur fracture. The accuracy of intraoperative reduction and surgical skill are important for the clinical outcome and the patients' prognosis.

Academic research paper on topic "Subtrochanteric femur fracture treated by intramedullary fixation"

Chinese Journal of Traumatology LPi L

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ELSEVIER journal homepage: http://www.elsevier.com/locate/CJTEE

Original article

Subtrochanteric femur fracture treated by intramedullary fixation

Zu-Bin Zhou a'b, Song Chen b, You-Shui Gao b, Yu-Qiang Sun b, Chang-Qing Zhang b, Yao Jiang a'b' *

a Medical College ofSoochow University, Shanghai 200233, China

b Department of Orthopaedic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, China

ARTICLE INFO ABSTRACT

Purpose: To discuss surgical technique, operative efficacy and clinical outcome of intramedullary fixation in the treatment of subtrochanteric femur fractures.

Methods: From February 2011 to February 2013, 76 cases of subtrochanteric femur fractures were treated by intramedullary fixation in our hospital, including 53 males and 23 females, with the age range of 37 —72 years (mean 53.5 years). According to Seinsheimer classification, there were 2 cases of type I, 7 type II, 15 type III, 23 type IV and 29 type V. Firstly, all patients underwent closed reduction with the guidance of C-arm fluoroscopy in a traction table. Two cases of type I and 3 cases of type III fractures had ideal closed reduction followed by internal fixation. The others needed additional limited open reduction. Radiographic examination was used to evaluate callus formation and fracture healing in postoperative 1,

3, 6 and 12 months follow-up. Functional recovery was evaluated by Harris Hip Scoring (HHS) system. Results: Patients were followed up for 6—12 months. All fractures were healed except one patient with delayed union. The average bone union time was 4.5 months. According to HHS system, 65 cases were considered as excellent in functional recovery, 8 good, 2 fair and 1 poor. The proportion of the patients with excellent and good recovery was 96.05%.

Conclusion: Intramedullary fixation is feasible for the treatment of subtrochanteric femur fracture. The accuracy of intraoperative reduction and surgical skill are important for the clinical outcome and the patients' prognosis.

© 2015 Production and hosting by Elsevier B.V. on behalf of Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. This is an open access article under the CC BY-NC-ND

license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Contents lists available at ScienceDirect

Chinese Journal of Traumatology

journal homepage: http://www.elsevier.com/locate/CJTEE

Article history: Received 24 August 2015 Received in revised form 1 November 2015 Accepted 7 November 2015 Available online 12 December 2015

Keywords:

Subtrochanteric femur fractures

Intramedullary nail

Surgical procedures, operative

1. Introduction

Subtrochanteric femur fracture is defined as a clinically rare fracture with the primary fracture line within 5 cm below the lesser trochanter. In 1949, Boyd and Griffin1 firstly described sub-trochanteric femur fractures and distinguished them from inter-trochanteric fracture, and they also noted the unsatisfactory postoperative outcomes in many subtrochanteric fracture patients. According to Koch's study,2 the compressive stress on medial cortex was as high as 1100 N, so the subtrochanteric fractures were usually comminuted fractures, which also indicated the necessity of reconstructing the medial cortex. The high transmitted stress is mostly concentrated on subtrochanteric area, which mainly constituted of thick cortical bone, with poor blood supply. Once a

fracture occurs, the process of healing is relatively slow. Following the fracture, the proximal and distal segments are deformed by forces produced by the surrounding musculature of the lesser and greater trochanters, to be specific, the proximal end is flexed and outwards rotated by the traction of iliopsoas and abducted by the force of hip short abductor muscle, the distal end is endoducted by the pulling of the great adductor muscle.3 High compressive, tensile forces of muscles separate the fracture segments and make sub-trochanteric fracture unstable. So there are no absolute contraindications for those cases, as long as the patients can tolerate surgery, surgical treatment is preferred. In this study, we retrospectively analyzed 76 cases of subtrochanteric femur fractures treated by intramedullary fixation in our hospital from February 2011 to February 2013.

* Corresponding author. Tel.: +86 18001826376. E-mail address: zhou_zubin@sina.com (Y. Jiang).

Peer review under responsibility of Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. http://dx.doi.org/10.1016/j.cjtee.2015.11.011

1008-1275/© 2015 Production and hosting by Elsevier B.V. on behalf of Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

2. Materials and methods

2.1. Clinical data

From February 2011 to February 2013, totally 76 cases of subtrochanteric femur fracture were treated with intramedullary fixation system in our hospital, achieving closed reduction. Two cases of type I and 3 of type III fractures had satisfactory closed reduction and treated with internal fixation, the other 72 cases underwent additional limited open reduction.

Inclusion criteria were: (1) the fracture line was located within 5 cm below the lesser trochanter and the patient was treated with intramedullary fixation; (2) interval from injury to operation <3 weeks; and (3) normal anatomic structure of proximal femur before fracture with no history of hip diseases. The patients with old subtrochanteric femur fracture, history of hip diseases or pathologic fracture were excluded.

All enrolled patients had complete follow-up data. There were 53 males and 23 females, with the age range of 37—72 years (mean 53.5 years). According to Seinsheimer classification, there were 2 cases of type I, 7 type II, 15 type III, 23 type IV and 29 type V. All the patients were examined by C-arm fluoroscopy in the traction bed.

2.2. Surgical treatment

In a supine position, patients underwent closed reduction in the fracture table. C-arm fluoroscopy was used to evaluate the accuracy of reduction. For the patients with unsatisfactory closed reduction, limited open reduction was performed. Taking the fracture end as the center, a 5—8 cm incision along skin soft tissue was made to separate and expose the fracture ends. The hematoma around the fracture segments was evacuated. For a simple fracture, a pointed clamp was used for provisional fixation to maintain the reduction. For complex or comminuted fractures, limited open reduction assisted by auxiliary devices (such as bone-holding forceps, reduction clamps) was adopted. All operative steps were accomplished under C-arm fluoroscopy until accurate reduction was achieved. In small incisions of the fracture ends, 1 to 2 cerclages were given to stabilize the fractured bone blocks.

After reduction, according to the intramedullary nail placement procedure, intramedullary fixation was performed. With femoral greater trochanter as the center, a 3—5 cm skin incision was made to separate soft tissue until the greater trochanter. The entry point of intramedullary nails was located in the vertex or medial side of greater trochanter, and lateral projection was in the front 1/3 of greater trochanter. Make an incision at the entry point and insert the needle. C-arm fluoroscopy in anterioposterior and lateral planes was used to ensure or adjust the position and angle of the needle. Then slightly ream until intramedullary nail can be properly inserted, using soft tissue protective sleeve to ensure the needle position and avoid lateral derivation. Afterwards, the antegrade intramedullary nailing of the right width and length was given, meanwhile the force line of the limbs and fracture position were properly maintained. Insert the nail until the right depth, install the guide, insert the proximal and distal locking screws and confirm the fracture position under C-arm fluoroscopy. Then install the tail cap, repeatedly rinse the wound, tighten the screws, place the drainage tube and close the wound.

2.3. Postoperative treatment

All patients were given prophylactic anti-infective treatment for postoperative 3 days, subcutaneous injection of low molecular heparin to prevent deep vein thrombosis during the hospital stay, and oral administration of clotting factor Xa inhibitors after

discharge. The exercise of muscle strength of lower limbs and functional exercises of hip joint were initiated immediately after operation, and weight-bearing was prohibited for postoperative 8—12 weeks. The physicians evaluated the postoperative radiographic results and decided the timing of weight-bearing exercises. The conventional X-ray examination of the injured hip in pelvic anterior-posterior and lateral planes was conducted at postoperative 3, 6, 12 months to assess the fracture healing, the morphology of hip joint and the implant status. After fracture healing, the Harris hip scoring system was used to evaluate the hip joint function.

2.4. Statistical analysis

All data were expressed as mean ± SD, and the maximum and minimum values were also listed. The statistical analysis was performed using the SPSS 20.0 software.

3. Results

All 76 cases of femoral subtrochanteric fracture were followed up for 6—24 months. One patient had delayed healing, and the others healed uneventfully. The fracture healing time was 4.5 months on average. According to Harris hip score, 65 cases were considered as excellent in functional recovery, 8 good, 2 fair and 1 poor. The proportion of the patients with excellent and good recovery was 96.05%.

In this study, 2 cases of type I and 3 cases of type III were treated with closed reduction and internal fixation. The remaining 71 patients received limited open reduction because of the unfavorable outcome of closed reduction under C-arm fluoroscopy. Among them, 66 patients underwent pointed clamp-assisted reduction followed by intramedullary fixation; since it was hard to fix the fractured bones using clamps in another 5 patients, the cerclage was given in the small incision of the fracture ends to stabilize the bone blocks, followed by intramedullary fixation. The treatment for typical cases is demonstrated in Figs. 1 and 2.

4. Discussion

Due to the anatomical features of subtrochanteric femur fractures, conservative treatment is not preferred. For elderly patients, long-term in-bed traction can lead to the complications including pressure ulcers, hypostatic pneumonia and deep vein thrombosis. Generally speaking, surgery is the optimal scheme for the patients with no absolute contraindications. Due to the low proportion of patients receiving conservative treatment, there were few literature about the efficacy of conservative treatment and the comparison between conservative treatment and internal fixation. In 1978, Vlasco et al4 retrospectively studied 82 cases and reported that 50% of 32 patients undergoing conservative treatment showed unfavorable results, including hip varus, shortening of limbs and rotational deformity, while the incidence of poor outcome in surgery group was only 21%. Seinsheimer et al5 made a retrospective study of 56 cases and reported that in 47 cases receiving surgery, 9 had internal fixation failure, 3 non-union (failure rate: 26%); 9 cases receiving conservative treatment were all healed, but 5 cases (56%) had hip varus deformity of 15°—29°.

4.1. Internal fixation—intramedullary or extramedullary?

With the development of internal fixation techniques, surgery is the mainstream of subtrochanteric fracture treatment. But the choice on fixation method has always been a controversial issue.

Fig. 1. A, B: Subtrochanteric fracture of left femur treated by limited open reduction and intramedullary fixation; C: postoperative 4 weeks; D: postoperative 12 weeks; E: intraoperative macroscopic view of the incisions (from left to right: a 3 cm-long incision for the distal nail, 4 cm for limited open reduction at fracture end, 2 cm for the proximal nail, 3 cm at the entry point).

From the perspective of biomechanics, intramedullary fixation has its unique advantage— short force arm, which can better distribute the stress, while extramedullary fixation can load the stress.6 Some scholars made a comparison study of intramedullary fixation and extramedullary fixation and proved a better consequence using intramedullary fixation. It is noticeable that these biomechanical

advantages of intramedullary fixation are based on the stable fracture patterns. For unstable fracture associated with obvious comminuted fractures, the stress can bypass bone defect and act on the distal screw, so no matter intramedullary or extramedullary fixation is adopted, there exists a possibility of breakage of distal screws. Roberts et al7 compared four kinds of second-generation

Fig. 2. Subtrochanteric femur fracture treated by limited open reduction and cerclage-assisted intramedullary fixation. A: preoperative X-ray and CT; B: postoperative 6 weeks; C: fracture healing at postoperative 12 weeks; D: intraoperative macroscopic view of the incisions (from left to right: a 3 cm-long incision for the distal nail, 6 cm for limited open reduction at fracture end + the proximal nail, 3 cm at the entry point).

intramedullary nails in the biomechanical experiment which simulated the treatment of different types of subtrochanteric fractures. The result showed that the choice of intramedullary nails is not crucial in simple fracture patterns, but if the fracture is deteriorated, especially accompanied by comminution and defects, the appropriate nails of right form, length and angle should be strictly chosen to minimize the disposition of fracture ends. Compared with extramedullary fixation, intramedullary fixation can prevent the medial displacement of distal segment, especially for the fracture with defects of medial cortex, the risk of

intramedullary fixation failure is low. Although intramedullary fixation can provide a stronger anti-bending and anti-compression capability, extramedullary fixation has a better antiglide capability.

Although intramedullary fixation has the advantages of biomechanical stability and less soft tissue damage, most studies have not confirmed the clinical superiority of intramedullary fixation over extramedullary fixation using steel plate and DHS. Cook et al8 made a retrospective study of 244 cases of subtrochanteric fractures treated by intramedullary and extramedullary fixation and found no significant difference in clinical outcome between the

two approaches. Lee et al9 reported a prospective study of 66 young patients with subtrochanteric femur fracture and revealed the similar therapeutical effects of DCS and Russel—Taylor reconstruction nail. In recent years, the researchers pay more attention to indirect reduction and the biological fixation. Some scholars performed locking plate fixation in a minimally invasive approach and obtained good outcomes.10 Saini et al11 treated Seinsheimer type III—V subtrochanteric fractures by indirect reduction and PF-LCP internal fixation, and the follow-up results showed that all 32 cases were healed, with the average healing course of 15.62 weeks, including 2 cases of delayed union, 2 cases of infection, 1 case of 1 cm shortening of limb, 2 cases of external rotation deformity, but no internal fixation failure occurred. Zhong et al12 compared the follow-up data of PF-LCP and DHS for the treatment of subtrochanteric femur fractures and found that compared with DHS, PF-LCP had shorter operation time, less bleeding, faster fracture healing, better hip joint function (Sanders score), and lower complication rate. It may be due to that DHS produces a bigger incision, more surgical blood loss, greater soft tissue injury and more damage to blood supply. Li et al13 reported 26 cases of subtrochanteric femur fractures treated by LISS: all fractures healed and no complications occurred in the follow-up of average 28 months, which was attributed to less bleeding and reliable stabilization according to Li's conclusion. Riehl et al14 reviewed 35 cases of subtrochanteric femur fractures treated by intramedullary nailing, the radiographic and clinical evidences showed that the deformity >10° in any plane would increase the probability of delayed union or nonunion. It seems that on the premise of blood supply preservation of fracture segments, accurate reduction is necessary for good functional recovery.

Everyone agrees that intramedullary fixation has biomechanical advantages, but why it does not show any clinical superiority? There are many influencing factors in clinical follow-up, including patient's age, fracture pattern, implants, reduction method, reduction outcome and postoperative function exercise, etc.2,15—18 Besides biomechanical advantages, intramedullary fixation causes small soft tissue injury and little intervention on fracture segments, so it protects blood supply to a large extent. But this is technically demanding for the operators. Even for the experienced orthopedic surgeons with expertise in extramedullary fixation, to master intramedullary fixation still needs a learning curve. Once the operation fails, even with the right internal fixator, the result will be disastrous. In the past, extramedullary fixation required a relatively large incision to directly expose the fracture segments, so it disrupted blood supply which was not adequate even in uninjured limbs. Having realized this dilemma, some scholars adopted closed reduction and used the minimally invasive method to place extramedullary fixation devices, such as proximal femoral locking compression plate (PF-LCP), less invasive stable system (LISS), achieved beneficial outcome in clinical follow-up.11—13 Therefore, the treatment of subtrochanteric femur fractures cannot simply count on intramedullary fixation. For some surgeons familiar with extramedullary fixation, closed reduction plus minimally invasive extramedullary fixation can be also applicable. The final outcome of surgery may not completely depend on the choice of implants for intramedullary and extramedullary fixation. To decrease damage on blood supply of fracture segments and achieve accurate reduction may be two key factors for successful treatment.

4.2. Reduction: closed or open or limited open?

Anatomical reduction was emphasized in early treatment of subtrochanteric femur fractures, and angular steel plate and DCS were once used for internal fixation. In this approach, the surgeon needs to dissect a lot of soft tissues in order to achieve satisfactory

reduction under the direct visualization, but the non-union rate was as high as 20%.19 Subsequently, extramedullary fixation can greatly reduce soft tissue injury and maintain intact soft tissue surrounding the fracture ends, thus decrease non-union rate. But due to the deformation of the flexion, adduction, external rotation in the proximal femur, the reduction of subtrochanteric femur fracture is challenging. There are two types of reduction, one is in lateral position from distal to proximal, and the other is the reduction by the force of traction in traction table. Reduction may fail in some fractures. The unsuccessful reduction may cause nonunion of fracture, even leading to internal fixation failure. The preservation of blood supply in fracture ends and accurate reduction seem to be contradictory in the treatment of subtrochanteric femur fractures.

To solve this problem, some scholars suggested that limited open reduction can decrease the interference on fracture ends, meanwhile maintain the stabilization and precision of reduc-tion.20—22 Beingessner et al23 treated subtrochanteric fractures by open reduction and intramedullary fixation and reported that all 56 patients had bone union without loss of reduction, 55 cases (98%) with coronal and sagittal plane deformity of less than 5°. But for unstable subtrochanteric femur fractures, the manipulation using pointed clamps is inadequate to maintain the reduction. Some researchers proposed wire cerclage of fracture ends to maintain the good reduction and force line for the following intramedullary nailing.24—30 Kim et al27 treated subtrochanteric fractures by percutaneous cerclage plus intramedullary fixation, all fractures healed and no implant-related complications occurred. Yoon et al31 described the technique of pointed clamp-assisted reduction. But because of the limitation of tools and methods, early cerclage placement required stripping a wide range of soft tissues, which brought damage to blood supply of fracture ends, moreover, more cerclage wires were used, so the follow-up results indicated a higher incidence of bone nonunion.32 Some scholars claimed that cerclage itself also affected blood supply. But some anatomical and histological studies confirmed that periosteal blood supply is circular rather than longitudinal.33—36 Therefore, Nather et al33 questioned the assumption that cerclage would block blood supply of periosteal vessels. With the technical advances, the currently used percutaneous cerclage can stabilize the fracture ends and preserve blood supply, causing little damage on soft tissue surrounding the fracture ends. Muller et al28 made a biomechanical analysis in 10 cadavers with subtrochanteric fractures and compared the cerclage group with uncerclage group. The result showed cerclage can not only achieve satisfactory reduction, but also be of great significance to maintain the integrity of the medial cortex and reduce the risk of bone nonunion and internal fixation failure. Kennedy et al37 summarized the 2-years follow-up results of 17 subtrochanteric fractures treated by cerclage plus dolichocephalic medullary nailing and figured out that cerclage is not detrimental for fracture healing, but the physician should control the number of used nails. The number and spacing of wire cerclage also have an influence on fracture healing. The physicians should compromise between the biological advantages of satisfactory reduction by cerclage and the disadvantages of the damage to soft tissue and periosteal blood supply, which indicating AO and BO principles.

4.3. Limitation and conclusion

In our study, subtrochanteric femur fracture was treated by intramedullary fixation. For most of the cases, we tried to preserve blood supply of fracture ends in limited open operation, and obtained the satisfactory reduction. The follow-up showed that all 76 cases healed well, with the hip joint function recovered. The

limitation of this study lied in two aspects: the retrospective study and no corresponding cases of extramedullary fixation as control. Based on the basic principle of fracture healing, the excellent reduction and blood supply preservation are two important factors for fracture healing and functional recovery of the limbs. For sub-trochanteric fractures, it is not easy to achieve the two during operation at the same time, so the physicians should weigh the pros and cons and choose the optimal scheme, which may be the key to avoid the malunion of fracture. Our study showed that intra-medullary fixation combined with limited open reduction is feasible and effective for the treatment of subtrochanteric femur fractures, however, long-term follow-up and further observation are still expected.

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