HIP. Z. Dewei, Y. Xiaobing. Patients and Methods We evaluated 34 patients aged < 50 years with a displaced fracture of the femoral neck who

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1 Z. Dewei, Y. Xiaobing From Zhongshan Hospital of Dalian University, Dalian, China HIP A retrospective analysis of the use of cannulated compression screws and a vascularised iliac bone graft in the treatment of displaced fracture of the femoral neck in patients aged < 50 years There is a high risk of the development of avascular necrosis of the femoral head and nonunion after the treatment of displaced subcapital fractures of the femoral neck in patients aged < 50 years. We retrospectively analysed the results following fixation with two cannulated compression screws and a vascularised iliac bone graft. We treated 18 women and 16 men with a mean age of 38.5 years (20 to 50) whose treatment included the use of an iliac bone graft based on the ascending branch of lateral femoral circumflex artery. There were 20 Garden grade III and 14 grade IV fractures. Clinical and radiological outcomes were evaluated. The mean follow-up was 5.4 years (2 to 10). In 30 hips (88%) union was achieved at a mean of 4.4 months (4 to 6). Nonunion occurred in four hips (12%) and these patients had a mean age of 46.5 years (42 to 50) and underwent revision to a hip replacement six months after operation. The time to union was dependent on age with younger patients achieving earlier union (p < 0.001). According to the Harris hip score which was available for 27 of the 30 hips with satisfactory union, excellent results were obtained in 15 (score 90 points), fair in ten (score 80 to 90 points), and poor in two hips ( 80 points). One patient aged 48 years developed avascular necrosis of femoral head six years after operation and underwent total hip replacement. The management of displaced subcapital fractures of the femoral neck, in patients aged < 50 years, with two cannulated compression screws and an iliac bone graft based on the ascending branch of lateral femoral circumflex artery, gives satisfactory results with a low rate of complication including avascular necrosis and nonunion. Cite this article: Bone Joint J 2014;96-B: Z. Dewei, MD, Orthopaedic Surgeon Y. Xiaobing, MD, Orthopaedic Surgeon Zhongshan Hospital of Dalian University, Department of Orthopaedics, No. 6 Jiefang Street, Dalian, Liaoning province , China. Correspondence should be sent to Dr Mr Z. Dewei; dldxyxb@163.com 2014 The British Editorial Society of Bone & Joint Surgery doi: / x.96b $2.00 Bone Joint J 2014;96-B: Received 30 November 2013; Accepted after revision 14 April 2014 Displaced fractures of the femoral neck in relatively young patients may be complicated by the development of avascular necrosis (AVN) of the femoral head or nonunion. 1-6 The reported incidence of AVN ranges from 6% and 42%, and that of nonunion ranges from 0% and 45%, (mean age 38 years (22 to 50)) Kalra and Anand 8 have demonstrated that the integrity of the blood supply is the key factor for treating these injuries. Sen et al 9 and LeCroy et al 10 have employed vascularised pedicle grafts, using either the iliac crest or the fibula, with rates of union of between 91% and 100%. However, this technique requires microsurgical facilities and has associated donorsite morbidity. 11 In a previous study, we found that a vascularised iliac crest bone graft based on the ascending branch of lateral femoral circumflex artery was straightforward to use, with little donor site damage and few complications. 11 The blood supply to the femoral head has historically been described as arising from three sources: 12 1) an extracapsular arterial ring located at the base of the femoral neck, 2) ascending cervical branches on the surface of the femoral neck and 3) arteries of the ligamentum teres (Fig. 1). These vessels are damaged in displaced intracapsular fractures with the additional problem of intra-osseous pressure exceeding diastolic blood pressure following intracapsular injury. 13,14 We report the medium-term results following the internal fixation of a displaced fracture of the femoral neck with two cannulated compression screws and an iliac crest bone graft, based on the ascending branch of lateral femoral circumflex artery. We anticipated this approach would prevent the development of AVN and nonunion. Patients and Methods We evaluated 34 patients aged < 50 years with a displaced fracture of the femoral neck who 1024 THE BONE & JOINT JOURNAL

2 A RETROSPECTIVE ANALYSIS OF THE USE OF CANNULATED COMPRESSION SCREWS AND A VASCULARISED ILIAC BONE GRAFT Extracapsular arterial ring 2. Ascending cervical branches 3. Arteries of the ligamentum teres 4. Interior femoral circumflex artery 5. Femoral artery Fig. 1 Anatomical illustration showing blood supply to the femoral head. 1. Femoral artery 2. Ascending branch of lateral femoral circumflex artery 3. Opening window at head neck 4. Cannulated compression screws Fig. 2 Diagrammatic representation of the operative technique. Fig. 3a Fig. 3b Figure 3a) - An intra-operative photograph showing: 1) ascending branch of lateral femoral circumflex artery (arrow); 2) the tensor fascia lata (arrow); 3) Rectus femoris fascia (arrow) and b) harvesting vascularised iliac bonegraft (arrow). were treated between January 2000 and December There were 18 women and 16 men, with a mean age of 38.5 years (20 to 50) who underwent this procedure for Garden grades 15 III (n = 20) and IV (n = 14) fractures of the femoral neck. The mean interval between presentation and surgery was 14.8 hours (0 to 48). A total of three patients were lost to follow-up, which was at a mean of 5.4 years (2 to 10). The surgical technique has been previously described. 11 A double-curved 12 cm-long incision was made along the line connecting the anterior superior iliac spine (ASIS) and the lateral margin of the patella, with the proximal end of the incision running along the iliac crest and extending 4 cm beyond the ASIS. Briefly, two cannulated compression screws were inserted with one positioned superiorly in the femoral head and the other inferiorly in the head, passing just above the calcar in order to retain sufficient space for the pedicled graft. The sartorius and the origin of rectus femoris were then partially released and the tensor fascia lata was retracted to expose the ascending branch of the lateral circumflex femoral artery. The separation was extended proximally towards the iliac crest to the origin of the tensor. Part of the iliac crest, approximately 5 cm long and 3 cm wide, was then exposed laterally from the ASIS with a vascular pedicle long enough to enable rotation of the graft to the femoral neck. The anterolateral capsule of femoral head and neck was incised in a t-shape, avoiding the inferior part of the VOL. 96-B, No. 8, AUGUST 2014

3 1026 Z. DEWEI, Y. XIAOBING Fig. 4b Fig. 4a Fig. 4c Pre-operative anteroposterior (AP) radiographs showing a) fracture of the femoral neck (Garden grade III), b) two cannulated compression screws and the vascularised iliac bone graft in situ, and c) bone healing one year after removal of the cannulated screws (lateral view radiographs not available). femoral neck in order to protect the basilar section of the arterial ring. An osteotome was used to create a supero-lateral cortical window of approximately 2 cm 2 cm, at the femoral head neck junction. The previously harvested vascularised bone graft was impacted into the femoral neck with dedicated instruments (Shandong Weigao Group, Weihai, China). During insertion, we took care not to compress the soft-tissue cuff containing the vessels to the bone graft. The implantation of the graft was completed with some pressure to achieve solid engagement which was confirmed by slightly moving the hip to confirm that the bone block would not be displaced (Figs 2 and 3). Skin traction was applied post-operatively to the leg to maintain the hip in 30 abduction in a neutral position for three weeks. The patients received prophylactic cephalosporins for 24 hours and non-steroidal anti-inflammatory medication was used for post-operative analgesia. Active exercises for the quadriceps were initiated 24 hours after operation. Generally, patients could undertake active abduction/adduction exercises of the hip with 20 to 30 repetitions three times each day. Non-weight bearing mobilisation proceeded as comfort permitted and toe-touch weightbearing started three weeks after the operation. Two crutches were exchanged for one 12 months after the operation depending on the radiological findings.16 Patients were reviewed clinically and radiologically at four to six months after the operation. Further radiographs, MRI and the completion of the Harris Hip Score (HHS)17 were performed at 12, 24 and 36 months. Digital Subtraction Angiography (DSA) was undertaken at 12 months follow-up. The screws were routinely removed between one year and 18 months after the operation when the completion of healing of the fracture had been confirmed by both three-dimensional CT and MRI (Fig. 4). THE BONE & JOINT JOURNAL

4 A RETROSPECTIVE ANALYSIS OF THE USE OF CANNULATED COMPRESSION SCREWS AND A VASCULARISED ILIAC BONE GRAFT 1027 Statistical analysis. This was performed using SPSS 18.0 software (SPSS Inc., Chicago, Illinois) using chi-squared testing. The level of significance was set as a p-value < Results At final follow-up, the mean HHS was 91.4 points (62 to 100) and the outcome was excellent in 15 hips (score 90 points), fair in ten hips (score 80 to 90 points), and poor in two hips (scores 80 points); three patients were lost to follow-up and four developed AVN of the femoral head (HHS < 60 points). The mean limb shortening was 2.1 cm (1 to 2.8). Union of the fracture was achieved in 30 patients (88.2%) at a mean of 18.5 weeks (16 to 24). In four patients, there was no evidence of union at six months after operation. The mean age of these patients was 46.5 years (16 to 20); they subsequently underwent total hip replacement (THR). These were regarded as failures. Younger patients achieved an earlier and a more reliable union (16 to 20 weeks; p < 0.001). One patient aged 54 years at six-years follow-up developed AVN according to plain radiographs, which was confirmed on MRI. Conversion to THR was undertaken. Coxa vara deformity was noted in four patients, defined as a neck-shaft angle of < 120. However, they had satisfactory function. There were no intra-operative complications but two patients had unilateral femoral vein thromboses after surgery, and one patient had chronic donor-site pain. Discussion The management of displaced fractures of the femoral neck in patients aged < 50 years may be complicated by the development of AVN and nonunion, and of coxa vara and limb shortening. 13,14 A variety of treatments have been tried. Lifeso and Younge 18 used internal fixation alone in three of their 28 young patients (mean age 38 years) with one patient developing AVN and another nonunion other patients were treated with corrective osteotomy and THR. Osteotomy has been used to alter the biomechanics at the fracture site to promote healing, both with or without internal fixation, 18 and in some cases with the addition of bone grafting. 19 The rates of AVN and nonunion following the use of osteotomy are between 6% and 42%, and 0% and 45%, respectively. 18 Bone grafting has been used in the treatment of fractures of the femoral neck. 19 Free fibular grafting has also been used with rates of AVN and nonunion of between 0% and 33%, and 0% and 17%, respectively, in patients with a mean age of 37 years (21 to 45). 20 However, this technique requires microsurgical facilities and has significant donor site morbidity. Reconstruction of the blood supply to the femoral head is the key to avoiding AVN and nonunion. 21,22 Our choice of a vascularised bone graft based on the ascending branch of the lateral circumflex femoral artery graft has several advantages: the ascending branch is a mean of 8.5 cm (standard deviation (SD) 3.1) in length, with a mean outer diameter of 3.2 mm (SD 0.9) at the origin, 11 it supplies an area where it is easy to harvest a bone graft with minimal morbidity and which can be easily rotated from the donor to the recipient site, and it does not adversely affect the functional recovery of the hip. The use of cannulated compression screws allows stable fixation with low intraosseous pressures. 23 In our study, reliable bony union was achieved in 30 patients (88%) with only one developing AVN as a late complication. Younger age appeared to be associated with more rapid healing. We consider that two cannulated compression screws for internal fixation and iliac graft based on the ascending branch of lateral femoral circumflex artery is an effective form of treatment in the management of patients < 45 years with displaced subcapital fractures of the femoral neck. We thank S. Z. Zhong and D. C. Xu (China Southern Medical University) for their support and advice. This paper was supported by China National Natural Science Foundation grants and National Science and Technology Support Program 2012BAI17B02 (to D. Zhao). No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. This article was primary edited by G. Scott and first proof edited by J. Scott. References 1. Xie X, Zhang C, Jin D, Chen S, Gao Y. Free vascularised fibular graft for neglected femoral neck fractures in young adults. Hip Int 2012;22: Kapoor A, Deety LV, John VZ, Devadoss S, Devadoss A. Management of neglected femoral neck fractures and nonunions using a novel triple surgery combination: an Indian experience. Int J Low Extrem Wounds 2012;11: Lin D, Lian K, Ding Z, Zhai W, Hong J. Proximal femoral locking plate with cannulated screws for the treatment of femoral neck fractures. Orthopedics 2012;35: Protzman RR, Burkhalter WE. Femoral-neck fractures in young adults. J Bone Joint Surg [Am] 1976;58-A: Robinson CM, Court-Brown CM, McQueen MM, Christie J. Hip fractures in adults younger than 50 years of age. Epidemiology and results. Clin Orthop Relat Res 1995;312: Swiontkowski MF, Winquist RA, Hansen ST Jr. Fractures of the femoral neck in patients between the ages of twelve and forty-nine years. J Bone Joint Surg [Am] 1984;66-A: Mathews V, Cabanela ME. Femoral neck nonunion treatment. Clin Orthop Relat Res 2004;419: Kalra M, Anand S. Valgus intertrochanteric osteotomy for neglected femoral neck fractures in young adults. Int Orthop 2001;25: Sen RK, Tripathy SK, Goyal T, et al. Osteosynthesis of femoral-neck nonunion with angle blade plate and autogenous fibular graft. Int Orthop 2012;36: LeCroy CM, Rizzo M, Gunneson EE, Urbaniak JR. Free vascularized fibular bone grafting in the management of femoral neck nonunion in patients younger than fifty years. J Orthop Trauma 2002;16: Zhao D, Xu D, Wang W, Cui X. Iliac graft vascularization for femoral head osteonecrosis. Clin Orthop Relat Res 2006;442: Zlotorowicz M, Czubak J, Kozinski P, Boguslawska-Walecka R. Imaging the vascularisation of the femoral head by CT angiography. J Bone Joint Surg [Br] 2012;94-B: Gjertsen JE, Lie SA, Vinje T, et al. More re-operations after uncemented than cemented hemiarthroplasty used in the treatment of displaced fractures of the femoral neck: an observational study of 11,116 hemiarthroplasties from a national register. J Bone Joint Surg [Br] 2012;94-B: Souder CD, Brennan ML, Brennan KL, et al. The rate of contralateral proximal femoral fracture following closed reduction and percutaneous pinning compared with arthroplasty for the treatment of femoral neck fractures. J Bone Joint Surg [Am] 2012;94-A: VOL. 96-B, No. 8, AUGUST 2014

5 1028 Z. DEWEI, Y. XIAOBING 15. Zahid M, Bin Sabir A, Asif N, et al. Fixation using cannulated screws and fibular strut grafts for fresh femoral neck fractures with posterior comminution. J Orthop Surg (Hong Kong) 2012;20: Kuhn M, Harris-Hayes M, Steger-May K, Pashos G, Clohisy JC. Total hip arthroplasty in patients 50 years or less: do we improve activity profiles? J Arthroplasty 2013;28: Zhao D, Xiaobing Y, Wang T, et al. Digital subtraction angiography in selection of the vascularized greater trochanter bone grafting for treatment of osteonecrosis of femoral head. Microsurgery 2013 (Epub). 18. Lifeso R, Younge D. The neglected hip fracture. J Orthop Trauma 1990;4: Nair N, Patro DK, Babu TA. Role of muscle pedicle bone graft as an adjunct to open reduction and internal fixation in the management of neglected and ununited femoral neck fracture in young adults: a prospective study of 17 cases. Eur J Orthop Surg Traumatol 2013 (Epub). 20. Nagi ON, Dhillon MS, Goni VG. Open reduction, internal fixation and fibular autografting for neglected fracture of the femoral neck. J Bone Joint Surg [Br] 1998;80- B: Liu BY, Zhao DW, Yu XB, et al. Effect of superior retinacular artery damage on osteonecrosis of the femoral head Chin Med J (Engl) 2013;126: Roshan A, Ram S. Early return to function in young adults with neglected femoral neck fractures. Clin Orthop Relat Res 2006;447: Lu QH, Yu FP. [Therapeutic effects of cannulated compression screws for treating femoral neck fractures]. Zhongguo Gu Shang 2012;25: [Article in Chinese]. THE BONE & JOINT JOURNAL