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Valgus intertrochanteric osteotomy and fibular strut graft in the management of neglected femoral neck fracture
Injury, Int. J. Care Injured 44 (2013) 763–768
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Valgus intertrochanteric osteotomy and fibular strut graft in the management of neglected femoral neck fracture Wasudeo M. Gadegone a,*, Alankar Ambadas Ramteke b, Vijayanand Lokhande a, Yogesh Salphade a a b
Department of Orthopaedics & Traumatology, Chandrapur Multispeciality Hospital, Mul Road, Chandrapur 442401, India Arthritis & Joint Replacement Clinic, Pushp-kunj Complex, Ramdaspeth, Nagpur 440010, India
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 19 September 2012
Purpose: A prospective study of neglected femoral neck fractures in mostly young patients was conducted to evaluate whether our technique of valgus intertrochanteric osteotomy with fibular strut grafting and osteosynthesis with dynamic hip screw and double-angle side plate can facilitate union with consistent satisfactory clinical outcomes. Methods: Forty-one consecutive patients (27 males, 14 females) of neglected femoral neck fractures treated between April 2002 and December 2009 were studied. The average age of patients was 45.41 years (11.67, range 20–62 years). The average interval since injury was 14 weeks (10.21, range 4–44 weeks). The cases were evaluated radiographically and clinically. Results: The average follow-up period was 32.5 months (8, range 24–54 months). Radiographically union was seen in 39 patients at the nonunion site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). Average Harris Hip Score (HHS) was 19.9 (7.9, range 10–35) preoperatively and 90.9 (10.35, range 62–100) at the latest follow-up. At that time clinical outcomes were excellent in 31, good in four, fair in three and poor in three patients. Conclusion: Our mechanobiological surgical technique is reproducible with radiographic union achieved in 95.12% cases (39 patients) at the nonunion site and consistent excellent or good functional outcome in 85% of patients over a 32-month average follow-up. We recommend this procedure for neglected femoral neck fractures. ß 2012 Elsevier Ltd. All rights reserved.
Keywords: Femur neck fracture Intertrochanteric osteotomy Dynamic hip screw Nonunion
Introduction One month or older fractures of the neck of femur are considered as neglected.1–3 Neglected femoral neck fractures pose additional problems such as osteopenia, resorption, difficulty in reduction and communition besides high frequency of failure associated with internal fixation alone.1–4 Delay in surgery leads to variable degrees of neck absorption, proximal migration of the greater trochanter (GT) and disuse osteoporosis with the ensuing co-morbidities.5 Existing treatment options include osteosynthesis without or with either free or vascularised bone graft,6–9 valgus osteotomy2,3 and hemiarthroplasty or total hip arthroplasty (THA).10,11 In spite of recent advances in treatment and outcome, results are variable and there is no universally accepted standard method of treatment.3,10,11
* Corresponding author at: Vivek Nagar, Mul Road, Chandrapur 442401, India. Tel.: +91 7172 253704; fax: +91 7172 254704. E-mail address: [email protected] (W.M. Gadegone). 0020–1383/$ – see front matter ß 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.injury.2012.09.014
Hip arthroplasty is an attractive option in the elderly.10,12–15 However, because of financial constraints, patients’ reluctance to undergo joint replacement and change a lifestyle that involves squatting and sitting cross-legged, we preferentially offer jointpreserving procedures to our patients. In younger patients, every effort is made to preserve the native hip.10,12 The purpose of this prospective study was to evaluate whether our technique of valgus intertrochanteric osteotomy with fibular strut grafting and osteosynthesis with dynamic hip screw (DHS) and double-angle side plate can facilitate union in neglected femoral neck fractures in young patients with consistent satisfactory clinical outcomes. Materials and methods This study was approved by the hospital ethical committee and informed consent was obtained from all patients prior to enrolment. Forty-two consecutive patients of neglected femoral neck fracture were treated between April 2002 and December 2009. All these patients had displaced intracapsular femoral neck fractures. One patient developed implant cut out in the immediate
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postoperative period and underwent a bipolar hemiarthroplasty and was excluded. The remaining 41 cases were considered for the present analysis. The average age was 45.41 years (11.67, range 20–62 years). There were 27 male and 14 female patients. The average interval since injury was 14 weeks (10.21, range 4–44 weeks). Four patients had hypertension and two patients had diabetes mellitus. Plain radiographs of the both hips were assessed for avascular necrosis (AVN),16 neck resorption,1 measurement of the Pauwels angle 17,18 and osteoporosis.19 There were seven Pauwel’s type II and 34 type III fractures in our series. No special investigations were performed to detect pre-collapse or AVN of femoral head due to limited resources. Preoperative magnetic resonance imaging (MRI) scan was available for four patients and AVN of the femoral head was not detected in any of them. Exclusion criteria were presence of more than two co-morbid factors, patients presenting less than 4 weeks since injury and age more than 65 years. All patients were operated under spinal (37 patients) or general anaesthesia (four patients). Preoperative planning was done on the pelvis with both hips’ antero-posterior (AP) radiographs. The fracture was reduced on a fracture table accurately by gentle traction in external rotation followed by internal rotation and abduction by about 208 and confirmed under an image intensifier in AP and lateral views. Only one patient needed open reduction of fracture. Via a direct lateral approach, the vastus lateralis muscle was released in the ‘L’ shape and lifted subperiosteally. An angle guide was used to pass two guide wires at an angle of 1108, to provisionally hold the reduction. The inferior guide wire was passed from the base of GT to the lower quadrant of the femoral head in AP view and central or posterior in lateral view. The second guide wire was passed superiorly and a 6.5 cancellous screw was inserted over it to stabilise the fracture to prevent displacement during the subsequent manipulations. This guide wire was subsequently removed. After due consideration of the tip–apex distance, a DHS of appropriate length was passed over the inferior guide wire.20 A 1108/1308 custom-made double-angle side plate was inserted over the screw leaving the side plate at an angle of approximately 208 from the lateral aspect of the femoral shaft. Now at the level of the elbow of the plate (which is usually at or just proximal to the level of the lesser trochanter (LT)) a femoral osteotomy was performed by creating space for the oscillating saw. A pre-determined wedge usually of 208 was removed and the shaft of the femur abducted and fixed to the plate by cortical screws. The length of the fibular graft required was assessed by the length of the superior screw. The outer part of the fibula of adequate length was removed by an oscillating saw from the middle third of the ipsilateral leg with the interosseous border kept intact. The cannulated cancellous screw was then removed. The fibular graft was inserted in the tunnel of the cancellous screw, by impaction up to the subchondral part of the femoral head under an image intensifier. The wound was closed in layers over a negative suction drain. No postoperative immobilisation was given. Isometric quadriceps exercises and knee bending were started on the second postoperative day. Non-weight-bearing ambulation on crutches was encouraged as soon as the pain subsided. Weight bearing was allowed after 6 weeks as pain permitted. Patients were assessed postoperatively at monthly intervals until radiographic union and at 3 months, 6 months and 1 year since surgery and yearly after that. Clinical assessment included evaluation for Harris Hip Score (HHS).21 Radiographs were assessed for signs of union and appearance of signs of AVN.16 Radiographic union was determined by the presence of bridging trabeculae across the fracture and the osteotomy site in both AP and lateral views. Unsupported weight bearing was allowed after radiographic union of the fracture.
Results The average follow-up period was 32.5 months (8, range 24– 54 months). The average HHS was 19.9 (7.9, range 10–35) preoperatively, 88.4 (9.45, range 63–97) at the end of first year and 90.9 (10.35, range 62–100) at the latest followup. At the end of the first year, clinical outcomes were excellent in 24, good in 11, fair in three and poor in three patients. At the latest follow-up, clinical outcomes were excellent in 31, good in four, fair in three and poor in three patients. Owing to only 208 correction, we removed smaller wedges, and the leg length discrepancy (LLD) in all patients was less than 2 cm. LLD was reported as per HHS.21 At the end of the first year, 17 patients had no limp and the rest had either slight (19) or moderate limp (5) on walking. At the latest follow-up, 28 patients had no limp and the rest had either slight (10) or moderate limp (3). Preoperatively, femoral head collapse was not observed in any radiographs. Postoperatively, seven patients developed radiographic signs of AVN and two out of these progressed to collapse of the femoral head during follow-up.16 One patient of AVN, with progressive collapse, underwent a bipolar hemiarthroplasty for pain. The remaining six patients had fair outcome on HHS evaluation at the latest follow-up. Even though terminal range of flexion was restricted in these patients, activities of daily living were not affected. Preoperatively, varying degree of neck resorption was observed in all patients. Thirty-three patients had type 3 and eight patients had type 2 Pauwels’ fracture pattern. Eight patients had grade 5 osteoporosis, seven patients had grade 4, 24 patients had grade 3 and one patient had grade 2.19 Radiographic union was seen in 39 patients at the nonunion site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). Radiographic union at osteotomy sites was seen in all patients. Nonunion was seen in two patients and underwent bipolar hemiarthroplasty. Superficial infection in two cases was controlled with regular dressings and change of antibiotics. There was no residual disability at the donor site, except transient lateral popliteal nerve involvement in one case. Discussion In developing countries, femoral neck fractures usually present late owing to factors such as neglect, mismanagement by bonesetters and delayed referral.1,22,23 In spite of hip arthroplasty being an attractive treatment option especially in the elderly,10,12–15 we preferentially offer joint preserving procedures to our patients. In younger patients, every effort is made to preserve the hip and joint replacement is used as a salvage procedure.10,12,24,25 There is no consensus as to the best treatment option and many methods of treatment such as osteosynthesis with cancellous screws, osteotomy with either displacement or angulation, osteosynthesis with cortico-cancellous graft with vascular pedicle3,6,7,10,11 and osteosynthesis with either vascularised or nonvascularised fibular grafts are reported.2,8,9,23 Valgus intertrochanteric osteotomy has the longest and most proven track record,26 and excellent results are reported in young27 and old.17 Femoral neck fracture nonunion is a mechanobiological problem18; hence, just a mechanical (fixation) or biological (grafting) solution is not enough, and a combination of the two must be used. Even though successful use of blade plate is reported,17,22,25 it is technically difficult.12 Greater risk of complications such as cutting out on insertion, displacement, fracture and less than satisfactory angular correction28 with angle blade plate fixation is reported as compared to DHS. In our series, intra-operative compression at the nonunion site was achieved10 in all cases, which was not possible with an angle blade plate alone. Lack of rotational control of the proximal
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Fig. 1. Anteroposterior (AP) radiographs of 42-years old male patient who presented with 9 weeks old neglected fracture of the neck of left femur. (a) Before surgery. (b) On follow up at 16 weeks post op fracture was united with union also seen at osteotomy site. (c) At latest follow up at 5 years post op, not only has the fracture united, but also proximal femoral anatomy is minimally altered, thus reducing the technical difficulties for a future hip replacement procedure, if need arises in any patient. (d) Lateral view of the same patient at 5 years post op; there is no sign of degeneration or avascular necrosis (AVN).
fragment, described as a disadvantage of the DHS,10 was overcome by passing a cannulated cancellous screw superiorly followed by appropriately sized DHS inferiorly. Once the DHS was introduced and fixed with a double-angle modified side pate, the proximal cannulated screw was withdrawn and a fibular graft was introduced, thus achieving the dual purpose of rotational stability by strut support as well as enhancing fracture biology via grafting.2,4
In our experience and previous reports, during fixation there occurred impingement of the side plate barrel against the lateral cortex of the shaft as the femoral neck was brought into valgus.10 As a result, there was a need to make a trough in the lateral cortex at the proximal edge of the shaft to accommodate the side plate barrel.10 Even in osteotomy with a blade plate fixation, the use of a double angle plate is recommended.1,3 Further, because of the lateral displacement of the GT fragment and medial displacement
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Fig. 2. A 58-years old patient with 3-month old neglected fracture of neck of left femur was operated with our technique of osteotomy. (a) Preoperative AP radiograph shows neck resorption and proximal migration of greater trochanter (GT). (b) Immediate post op radiograph reveals anatomical reduction, with restoration of neck length. (c) At 55 months latest follow up, fracture as well as osteotomy site have united well with restoration of position of greater trochanter, no signs of degeneration or AVN.
of the distal fragment, the anatomy of the proximal femur was disturbed in previous reports.12 Therefore, we used a modified double-angle side plate. Compression at the nonunion site was achieved by DHS; stable fixation at the osteotomy site was achieved by the DHS – side plate construct and maximum bony contact at the osteotomy site with near-anatomical alignment of the proximal femur was obtained by the double-angle configuration of the side plate (Fig. 1). This was done on purpose to minimally alter the proximal femur anatomy, for a future joint replacement if needed. In another report of DHS with partialthickness wedge osteotomy, the surgical technique led to decreased surface area of contact and inherent risk on non union and implant failure.12 Our technique ensured maximum bony
contact at the osteotomy site and the displacements associated with other techniques were addressed.12 A wedge of bone required to achieve 208 of abduction was removed at the LT level and was enough to change the inclination of fracture line (Fig. 2). If more than a 308 wedge is removed, a valgus orientation of the proximal femur is created. This decreases the lever arm and therefore increases contact pressure on the femoral head. This may in turn lead to progression of osteonecrosis or degeneration.29 Lengthening of the acetabulo-trochanteric distance occurs, which may stretch the abductor muscles and capsule, which would further compromise the precarious capsular circulation.30 In our study, we have used HHS for clinical evaluation. The average preoperative HHS was 19.9 (7.9, range 10–35), 88.4
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(9.45, range 63–97) at the end of the first year and 90.92 (10.26, range 62–100) at the latest follow-up. Eighty-five percent of our 41 patients had excellent (24) or good (11) clinical outcome at the end of the first year, and at the final follow-up, 85% patients had either excellent (31) or good (4) clinical outcome. Most studies have subjective outcome assessment and only few studies reported objective scores such as HHS or Merle D’Aubigne score and good functional outcome has been reported in 33–82% patients.2 Owing to only 208 correction, we removed smaller wedges and LLD was less than 2 cm. To facilitate scoring and uniform reporting via HHS, we reported LLD as either more or less than 3.2 cm.21 LLD has not been a problem even in other reports of valgus osteotomy.1,10,12 Even though 59% of our patients had a limp on
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walking at the end of the first year, at the latest follow-up 32% of patients had a slight or a moderate limp. The reported incidence of limp after a valgus osteotomy varies from 11% to 57%.1,10 Radiographically, union was seen in 95.12% cases (39 patients) at the nonunion site and in all patients at osteotomy site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). The rate of union for valgus osteotomy reported varies from 71% to 100%.1,12,17,25 The average time to union for a valgus osteotomy reported in the literature varies from 8 to 20 weeks.1,10,12,17 Preoperative neck resorption was observed in all patients. In two patients who underwent nonunion, neck resorption was more than half the length of the neck. Authors suggest that more than half the neck length must be present to achieve union and the
Fig. 3. A 32-years old male patient presented with 8-months old neglected fracture of neck of left femur. (a) Preoperative AP radiographs reveal displacement with neck resorption. However there are no radiographic signs of AVN. (b) Fracture of the neck of femur as well as osteotomy site united in 14 weeks post op as seen from this radiograph. (c) During 2 years follow up this patient developed collapse of the weight bearing zone of femoral head as seen on this AP radiograph. (d) However there is no further collapse or signs of degeneration on subsequent followup, which may be attributed to the fibular strut graft as seen on this lateral radiograph.
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threads of the screw must be secured inside the head. In our series, on evaluation for grade of osteoporosis, it was found that advanced grade of osteoporosis was not associated with nonunion or adverse outcome. Authors attribute no effect of osteoporosis on union or functional outcome to the use of fibular strut graft and stable mechanical fixation. On review of all treatment modalities including (i) internal fixation with/without grafting, (ii) internal fixation and osteotomy with/without grafting, (iii) non-vascularised as well as vascular grafts, reported incidence of non union ranges from 5% to 45%.2 As compared to that reported in the literature,2 the incidence of nonunion in our series is in the lower range (4.9%). We attribute the lower incidence of nonunion in our cases to the mechanobiological combination of our surgical technique, choice of implant for fixation and use of fibular strut graft. The fibular grafts helps in stability and the union of fractures. Radiographic signs of AVN 16 developed in seven patients during follow-up (Fig. 3). The incidence of AVN ranges between 0% and 67% with most reports being <15%.2 The reported incidence of AVN after valgus osteotomy with a non-vascularised graft varies from 0% to 75%.2 In a previous report of valgus intertrochanteric osteotomy in children, signs of AVN improved in three patients over 12–18 months and appeared in another after 60 weeks.1 In another report with angled blade plates, signs of AVN improved in two patients but three patients showed progression and collapse necessitating hip replacement.17 In reports where DHS fixation was used no AVN necrosis was reported.10,12 In our series, the fibular strut graft may be responsible for preventing collapse in five out of seven patients by mechanical support and/or revascularisation. All patients were evaluated preoperatively for the presence of AVN on radiographs16 only and not by MRI. We consider this as a weakness of our study. Preoperative MRI was available for five patients and MRI was not feasible in the rest due to financial constraints. Even though this is a prospective study, a randomised comparative study of two groups with or without use of a fibular graft is ideally recommended and authors believe that the absence of a randomised comparison group is a weakness of our study. Our surgical technique is reproducible with radiological union in 39 out of 41 patients and consistent excellent or good functional outcome in 85% of patients over a 32-month follow-up. We believe 208 angle of and a smaller wedge correction is necessary and sufficient as it does not stretch the capsule and has a favourable effect on capsular blood supply. Close reduction preserves the retinacular blood supply vital for fracture union. Intact blood supply from the ligamentum teres may facilitate revascularisation of both the femoral head and across the fracture in a stable mechanobiological environment provided by our technique.31 Union might be aided by bone dust from reaming by the 9 mm DHS reamer acting as an internal bone graft. Conclusion Valgus intertrochanteric osteotomy with fibular grafting is an effective procedure to achieve union in neglected femoral neck fractures in young patients less than 60 years of age. Internal fixation with DHS and double angle side plate is technically simpler. We recommend joint replacements only as a salvage procedure. Conflict of interest statement It is here by declared that none of the authors have any financial and personal relationships with other people or organisations that could inappropriately influence (bias) this work submitted for publication in your esteemed journal and that no funding or sponsorship was received for this study.
References 1. Magu NK, Singh R, Sharma AK, Ummat V. Modified Pauwels’ intertrochanteric osteotomy in neglected femoral neck fractures in children: a report of 10 cases followed for a minimum of 5 years. Journal of Orthopaedic Trauma 2007;21(4):237–43. 2. Roshan A, Ram S. The neglected femoral neck fracture in young adults: review of a challenging problem. Clinical Medicine and Research 2008;6(1):33–9. 3. Kalra M, Anand S. Valgus intertrochanteric osteotomy for neglected femoral neck fractures in young adults. International Orthopaedics 2001;25(6):363–6. 4. Kainth GS, Yuvarajan P, Maini L, Kumar V. Neglected femoral neck fractures in adults. Journal of Orthopaedic Surgery 2011;19(1):13–7. 5. Swiontkowski MF. Intracapsular fractures of the hip. The Journal of Bone and Joint Surgery American Volume 1994;76(1):129–38. 6. Baksi DP. Internal fixation of ununited femoral neck fractures combined with muscle-pedicle bone grafting. The Journal of Bone and Joint Surgery British Volume 1986;68(2):239–45. 7. Meyers MH, Harvey Jr JP, Moore TM. Delayed treatment of subcapital and transcervical fractures of the neck of the femur with internal fixation and a muscle pedicle bone graft. Orthopaedic Clinics of North America 1974;5(4):743–56. 8. Dooley BJ, Hooper J. Fibular bone grafting for non union of fracture of the neck of the femur. Australian and New Zealand Journal of Surgery 1982;52(2):134–40. 9. Slater RN, Gore R, Slater GJ. Free fibular bone grafting for femoral neck fractures: precise graft placement using a ‘cannulated screw’ technique. Journal of the Royal College of Surgeons of Edinburgh 1993;38(6):376–7. 10. Hartford JM, Patel A, Powell J. Intertrochanteric osteotomy using a dynamic hip screw for femoral neck nonunion. Journal of Orthopaedic Trauma 2005;19(5):329–33. 11. Jain NB, Losina E, Ward DM, Harris MB, Katz JN. Trends in surgical management of femoral neck fractures in the United States. Clinical Orthopaedics and Related Research 2008;466(12):3116–22. 12. Schoenfeld AJ, Vrabec GA. Valgus osteotomy of the proximal femur with sliding hip screw for the treatment of femoral neck nonunions: the technique, a case series, and literature review. Journal of Orthopaedic Trauma 2006;20(7):485–91. 13. Jackson M, Learmonth ID. The treatment of nonunion after intracapsular fracture of the proximal femur. Clinical Orthopaedics and Related Research 2002;(399):119–28. 14. Mathews V, Cabanela ME. Femoral neck nonunion treatment. Clinical Orthopaedics and Related Research 2004;(419):57–64. 15. Rudelli S, Viriato SP, Meireles TL, Frederico TN. Treatment of displaced neck fractures of the femur with total hip arthroplasty. The Journal of Arthroplasty 2012;27(2):246–52. 16. Ficat RP. Idiopathic bone necrosis of the femoral head. Early diagnosis and treatment. The Journal of Bone and Joint Surgery British Volume 1985;67(1):3–9. 17. Marti RK, Schuller HM, Raaymakers EL. Intertrochanteric osteotomy for nonunion of the femoral neck. The Journal of Bone and Joint Surgery British Volume 1989;71(5):782–7. 18. Mueller ME. The intertrochanteric osteotomy and pseudarthrosis of the femoral neck. 1957. Clinical Orthopaedics and Related Research 1999;(363):5–8. 19. Singh M, Nagrath AR, Maini PS. Changes in trabecular pattern of the upper end of the femur as an index of osteoporosis. The Journal of Bone and Joint Surgery American Volume 1970;52(3):457–67. 20. Baumgaertner MR, Curtin SL, Lindskog DM, Keggi JM. The value of the tip-apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. The Journal of Bone and Joint Surgery American Volume 1995;77(7):1058–64. 21. Harris WH. Traumatic arthritis of the hip after dislocation and acetabular fractures: treatment by mold arthroplasty. An end-result study using a new method of result evaluation. The Journal of Bone and Joint Surgery American Volume 1969;51(4):737–55. 22. Anglen JO. Intertrochanteric osteotomy for failed internal fixation of femoral neck fracture. Clinical Orthopaedics and Related Research 1997;(341):175–82. 23. Nagi ON, Dhillon MS, Gill SS. Fibular osteosynthesis for delayed type II and type III femoral neck fractures in children. Journal of Orthopaedic Trauma 1992;6(3):306–13. 24. Gingras MB, Clarke J, Evarts CM. Prosthetic replacement in femoral neck fractures. Clinical Orthopaedics and Related Research 1980;(152):147–57. 25. Said GZ, Farouk O, Said HG. Valgus intertrochanteric osteotomy with singleangled 130 degrees plate fixation for fractures and non-unions of the femoral neck. International Orthopaedics 2010;34(8):1291–5. 26. Haidukewych GJ, Berry DJ. Salvage of failed treatment of hip fractures. The Journal of the American Academy of Orthopaedic Surgeons 2005;13(2):101–9. 27. Rinaldi E, Marenghi P, Negri V. Osteosynthesis with valgus osteotomy in the primary treatment of subcapital fractures of the neck of the femur. Italian Journal of Orthopaedics Traumatology 1984;10(3):313–20. 28. Varshney MK, Trikha V. Intertrochanteric osteotomy using a dynamic hip screw for femoral neck nonunion. Journal of Orthopaedic Trauma 2005;19(10):751. [J Orthop Trauma 2005; 19: 329-333, author reply 751]. 29. Pauwels F. Biomechanics of the normal and diseased hip. Berlin: Springer; 1976. p. 129–271. 30. Frangakis EK. Intracapsular fractures of the neck of the femur. Factors influencing non-union and ischaemic necrosis. Journal of Bone and Joint Surgery British Volume 1966;48(1):17–30. 31. Catto M. A histological study of avascular necrosis of the femoral head after transcervical fracture. Journal of Bone and Joint Surgery British Volume 1965;47(4):749–76.
Contents lists available at SciVerse ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Valgus intertrochanteric osteotomy and fibular strut graft in the management of neglected femoral neck fracture Wasudeo M. Gadegone a,*, Alankar Ambadas Ramteke b, Vijayanand Lokhande a, Yogesh Salphade a a b
Department of Orthopaedics & Traumatology, Chandrapur Multispeciality Hospital, Mul Road, Chandrapur 442401, India Arthritis & Joint Replacement Clinic, Pushp-kunj Complex, Ramdaspeth, Nagpur 440010, India
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 19 September 2012
Purpose: A prospective study of neglected femoral neck fractures in mostly young patients was conducted to evaluate whether our technique of valgus intertrochanteric osteotomy with fibular strut grafting and osteosynthesis with dynamic hip screw and double-angle side plate can facilitate union with consistent satisfactory clinical outcomes. Methods: Forty-one consecutive patients (27 males, 14 females) of neglected femoral neck fractures treated between April 2002 and December 2009 were studied. The average age of patients was 45.41 years (11.67, range 20–62 years). The average interval since injury was 14 weeks (10.21, range 4–44 weeks). The cases were evaluated radiographically and clinically. Results: The average follow-up period was 32.5 months (8, range 24–54 months). Radiographically union was seen in 39 patients at the nonunion site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). Average Harris Hip Score (HHS) was 19.9 (7.9, range 10–35) preoperatively and 90.9 (10.35, range 62–100) at the latest follow-up. At that time clinical outcomes were excellent in 31, good in four, fair in three and poor in three patients. Conclusion: Our mechanobiological surgical technique is reproducible with radiographic union achieved in 95.12% cases (39 patients) at the nonunion site and consistent excellent or good functional outcome in 85% of patients over a 32-month average follow-up. We recommend this procedure for neglected femoral neck fractures. ß 2012 Elsevier Ltd. All rights reserved.
Keywords: Femur neck fracture Intertrochanteric osteotomy Dynamic hip screw Nonunion
Introduction One month or older fractures of the neck of femur are considered as neglected.1–3 Neglected femoral neck fractures pose additional problems such as osteopenia, resorption, difficulty in reduction and communition besides high frequency of failure associated with internal fixation alone.1–4 Delay in surgery leads to variable degrees of neck absorption, proximal migration of the greater trochanter (GT) and disuse osteoporosis with the ensuing co-morbidities.5 Existing treatment options include osteosynthesis without or with either free or vascularised bone graft,6–9 valgus osteotomy2,3 and hemiarthroplasty or total hip arthroplasty (THA).10,11 In spite of recent advances in treatment and outcome, results are variable and there is no universally accepted standard method of treatment.3,10,11
* Corresponding author at: Vivek Nagar, Mul Road, Chandrapur 442401, India. Tel.: +91 7172 253704; fax: +91 7172 254704. E-mail address: [email protected] (W.M. Gadegone). 0020–1383/$ – see front matter ß 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.injury.2012.09.014
Hip arthroplasty is an attractive option in the elderly.10,12–15 However, because of financial constraints, patients’ reluctance to undergo joint replacement and change a lifestyle that involves squatting and sitting cross-legged, we preferentially offer jointpreserving procedures to our patients. In younger patients, every effort is made to preserve the native hip.10,12 The purpose of this prospective study was to evaluate whether our technique of valgus intertrochanteric osteotomy with fibular strut grafting and osteosynthesis with dynamic hip screw (DHS) and double-angle side plate can facilitate union in neglected femoral neck fractures in young patients with consistent satisfactory clinical outcomes. Materials and methods This study was approved by the hospital ethical committee and informed consent was obtained from all patients prior to enrolment. Forty-two consecutive patients of neglected femoral neck fracture were treated between April 2002 and December 2009. All these patients had displaced intracapsular femoral neck fractures. One patient developed implant cut out in the immediate
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postoperative period and underwent a bipolar hemiarthroplasty and was excluded. The remaining 41 cases were considered for the present analysis. The average age was 45.41 years (11.67, range 20–62 years). There were 27 male and 14 female patients. The average interval since injury was 14 weeks (10.21, range 4–44 weeks). Four patients had hypertension and two patients had diabetes mellitus. Plain radiographs of the both hips were assessed for avascular necrosis (AVN),16 neck resorption,1 measurement of the Pauwels angle 17,18 and osteoporosis.19 There were seven Pauwel’s type II and 34 type III fractures in our series. No special investigations were performed to detect pre-collapse or AVN of femoral head due to limited resources. Preoperative magnetic resonance imaging (MRI) scan was available for four patients and AVN of the femoral head was not detected in any of them. Exclusion criteria were presence of more than two co-morbid factors, patients presenting less than 4 weeks since injury and age more than 65 years. All patients were operated under spinal (37 patients) or general anaesthesia (four patients). Preoperative planning was done on the pelvis with both hips’ antero-posterior (AP) radiographs. The fracture was reduced on a fracture table accurately by gentle traction in external rotation followed by internal rotation and abduction by about 208 and confirmed under an image intensifier in AP and lateral views. Only one patient needed open reduction of fracture. Via a direct lateral approach, the vastus lateralis muscle was released in the ‘L’ shape and lifted subperiosteally. An angle guide was used to pass two guide wires at an angle of 1108, to provisionally hold the reduction. The inferior guide wire was passed from the base of GT to the lower quadrant of the femoral head in AP view and central or posterior in lateral view. The second guide wire was passed superiorly and a 6.5 cancellous screw was inserted over it to stabilise the fracture to prevent displacement during the subsequent manipulations. This guide wire was subsequently removed. After due consideration of the tip–apex distance, a DHS of appropriate length was passed over the inferior guide wire.20 A 1108/1308 custom-made double-angle side plate was inserted over the screw leaving the side plate at an angle of approximately 208 from the lateral aspect of the femoral shaft. Now at the level of the elbow of the plate (which is usually at or just proximal to the level of the lesser trochanter (LT)) a femoral osteotomy was performed by creating space for the oscillating saw. A pre-determined wedge usually of 208 was removed and the shaft of the femur abducted and fixed to the plate by cortical screws. The length of the fibular graft required was assessed by the length of the superior screw. The outer part of the fibula of adequate length was removed by an oscillating saw from the middle third of the ipsilateral leg with the interosseous border kept intact. The cannulated cancellous screw was then removed. The fibular graft was inserted in the tunnel of the cancellous screw, by impaction up to the subchondral part of the femoral head under an image intensifier. The wound was closed in layers over a negative suction drain. No postoperative immobilisation was given. Isometric quadriceps exercises and knee bending were started on the second postoperative day. Non-weight-bearing ambulation on crutches was encouraged as soon as the pain subsided. Weight bearing was allowed after 6 weeks as pain permitted. Patients were assessed postoperatively at monthly intervals until radiographic union and at 3 months, 6 months and 1 year since surgery and yearly after that. Clinical assessment included evaluation for Harris Hip Score (HHS).21 Radiographs were assessed for signs of union and appearance of signs of AVN.16 Radiographic union was determined by the presence of bridging trabeculae across the fracture and the osteotomy site in both AP and lateral views. Unsupported weight bearing was allowed after radiographic union of the fracture.
Results The average follow-up period was 32.5 months (8, range 24– 54 months). The average HHS was 19.9 (7.9, range 10–35) preoperatively, 88.4 (9.45, range 63–97) at the end of first year and 90.9 (10.35, range 62–100) at the latest followup. At the end of the first year, clinical outcomes were excellent in 24, good in 11, fair in three and poor in three patients. At the latest follow-up, clinical outcomes were excellent in 31, good in four, fair in three and poor in three patients. Owing to only 208 correction, we removed smaller wedges, and the leg length discrepancy (LLD) in all patients was less than 2 cm. LLD was reported as per HHS.21 At the end of the first year, 17 patients had no limp and the rest had either slight (19) or moderate limp (5) on walking. At the latest follow-up, 28 patients had no limp and the rest had either slight (10) or moderate limp (3). Preoperatively, femoral head collapse was not observed in any radiographs. Postoperatively, seven patients developed radiographic signs of AVN and two out of these progressed to collapse of the femoral head during follow-up.16 One patient of AVN, with progressive collapse, underwent a bipolar hemiarthroplasty for pain. The remaining six patients had fair outcome on HHS evaluation at the latest follow-up. Even though terminal range of flexion was restricted in these patients, activities of daily living were not affected. Preoperatively, varying degree of neck resorption was observed in all patients. Thirty-three patients had type 3 and eight patients had type 2 Pauwels’ fracture pattern. Eight patients had grade 5 osteoporosis, seven patients had grade 4, 24 patients had grade 3 and one patient had grade 2.19 Radiographic union was seen in 39 patients at the nonunion site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). Radiographic union at osteotomy sites was seen in all patients. Nonunion was seen in two patients and underwent bipolar hemiarthroplasty. Superficial infection in two cases was controlled with regular dressings and change of antibiotics. There was no residual disability at the donor site, except transient lateral popliteal nerve involvement in one case. Discussion In developing countries, femoral neck fractures usually present late owing to factors such as neglect, mismanagement by bonesetters and delayed referral.1,22,23 In spite of hip arthroplasty being an attractive treatment option especially in the elderly,10,12–15 we preferentially offer joint preserving procedures to our patients. In younger patients, every effort is made to preserve the hip and joint replacement is used as a salvage procedure.10,12,24,25 There is no consensus as to the best treatment option and many methods of treatment such as osteosynthesis with cancellous screws, osteotomy with either displacement or angulation, osteosynthesis with cortico-cancellous graft with vascular pedicle3,6,7,10,11 and osteosynthesis with either vascularised or nonvascularised fibular grafts are reported.2,8,9,23 Valgus intertrochanteric osteotomy has the longest and most proven track record,26 and excellent results are reported in young27 and old.17 Femoral neck fracture nonunion is a mechanobiological problem18; hence, just a mechanical (fixation) or biological (grafting) solution is not enough, and a combination of the two must be used. Even though successful use of blade plate is reported,17,22,25 it is technically difficult.12 Greater risk of complications such as cutting out on insertion, displacement, fracture and less than satisfactory angular correction28 with angle blade plate fixation is reported as compared to DHS. In our series, intra-operative compression at the nonunion site was achieved10 in all cases, which was not possible with an angle blade plate alone. Lack of rotational control of the proximal
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Fig. 1. Anteroposterior (AP) radiographs of 42-years old male patient who presented with 9 weeks old neglected fracture of the neck of left femur. (a) Before surgery. (b) On follow up at 16 weeks post op fracture was united with union also seen at osteotomy site. (c) At latest follow up at 5 years post op, not only has the fracture united, but also proximal femoral anatomy is minimally altered, thus reducing the technical difficulties for a future hip replacement procedure, if need arises in any patient. (d) Lateral view of the same patient at 5 years post op; there is no sign of degeneration or avascular necrosis (AVN).
fragment, described as a disadvantage of the DHS,10 was overcome by passing a cannulated cancellous screw superiorly followed by appropriately sized DHS inferiorly. Once the DHS was introduced and fixed with a double-angle modified side pate, the proximal cannulated screw was withdrawn and a fibular graft was introduced, thus achieving the dual purpose of rotational stability by strut support as well as enhancing fracture biology via grafting.2,4
In our experience and previous reports, during fixation there occurred impingement of the side plate barrel against the lateral cortex of the shaft as the femoral neck was brought into valgus.10 As a result, there was a need to make a trough in the lateral cortex at the proximal edge of the shaft to accommodate the side plate barrel.10 Even in osteotomy with a blade plate fixation, the use of a double angle plate is recommended.1,3 Further, because of the lateral displacement of the GT fragment and medial displacement
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Fig. 2. A 58-years old patient with 3-month old neglected fracture of neck of left femur was operated with our technique of osteotomy. (a) Preoperative AP radiograph shows neck resorption and proximal migration of greater trochanter (GT). (b) Immediate post op radiograph reveals anatomical reduction, with restoration of neck length. (c) At 55 months latest follow up, fracture as well as osteotomy site have united well with restoration of position of greater trochanter, no signs of degeneration or AVN.
of the distal fragment, the anatomy of the proximal femur was disturbed in previous reports.12 Therefore, we used a modified double-angle side plate. Compression at the nonunion site was achieved by DHS; stable fixation at the osteotomy site was achieved by the DHS – side plate construct and maximum bony contact at the osteotomy site with near-anatomical alignment of the proximal femur was obtained by the double-angle configuration of the side plate (Fig. 1). This was done on purpose to minimally alter the proximal femur anatomy, for a future joint replacement if needed. In another report of DHS with partialthickness wedge osteotomy, the surgical technique led to decreased surface area of contact and inherent risk on non union and implant failure.12 Our technique ensured maximum bony
contact at the osteotomy site and the displacements associated with other techniques were addressed.12 A wedge of bone required to achieve 208 of abduction was removed at the LT level and was enough to change the inclination of fracture line (Fig. 2). If more than a 308 wedge is removed, a valgus orientation of the proximal femur is created. This decreases the lever arm and therefore increases contact pressure on the femoral head. This may in turn lead to progression of osteonecrosis or degeneration.29 Lengthening of the acetabulo-trochanteric distance occurs, which may stretch the abductor muscles and capsule, which would further compromise the precarious capsular circulation.30 In our study, we have used HHS for clinical evaluation. The average preoperative HHS was 19.9 (7.9, range 10–35), 88.4
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(9.45, range 63–97) at the end of the first year and 90.92 (10.26, range 62–100) at the latest follow-up. Eighty-five percent of our 41 patients had excellent (24) or good (11) clinical outcome at the end of the first year, and at the final follow-up, 85% patients had either excellent (31) or good (4) clinical outcome. Most studies have subjective outcome assessment and only few studies reported objective scores such as HHS or Merle D’Aubigne score and good functional outcome has been reported in 33–82% patients.2 Owing to only 208 correction, we removed smaller wedges and LLD was less than 2 cm. To facilitate scoring and uniform reporting via HHS, we reported LLD as either more or less than 3.2 cm.21 LLD has not been a problem even in other reports of valgus osteotomy.1,10,12 Even though 59% of our patients had a limp on
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walking at the end of the first year, at the latest follow-up 32% of patients had a slight or a moderate limp. The reported incidence of limp after a valgus osteotomy varies from 11% to 57%.1,10 Radiographically, union was seen in 95.12% cases (39 patients) at the nonunion site and in all patients at osteotomy site. The average time to radiographic union was 16.82 weeks (3 weeks, range 12–24 weeks). The rate of union for valgus osteotomy reported varies from 71% to 100%.1,12,17,25 The average time to union for a valgus osteotomy reported in the literature varies from 8 to 20 weeks.1,10,12,17 Preoperative neck resorption was observed in all patients. In two patients who underwent nonunion, neck resorption was more than half the length of the neck. Authors suggest that more than half the neck length must be present to achieve union and the
Fig. 3. A 32-years old male patient presented with 8-months old neglected fracture of neck of left femur. (a) Preoperative AP radiographs reveal displacement with neck resorption. However there are no radiographic signs of AVN. (b) Fracture of the neck of femur as well as osteotomy site united in 14 weeks post op as seen from this radiograph. (c) During 2 years follow up this patient developed collapse of the weight bearing zone of femoral head as seen on this AP radiograph. (d) However there is no further collapse or signs of degeneration on subsequent followup, which may be attributed to the fibular strut graft as seen on this lateral radiograph.
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threads of the screw must be secured inside the head. In our series, on evaluation for grade of osteoporosis, it was found that advanced grade of osteoporosis was not associated with nonunion or adverse outcome. Authors attribute no effect of osteoporosis on union or functional outcome to the use of fibular strut graft and stable mechanical fixation. On review of all treatment modalities including (i) internal fixation with/without grafting, (ii) internal fixation and osteotomy with/without grafting, (iii) non-vascularised as well as vascular grafts, reported incidence of non union ranges from 5% to 45%.2 As compared to that reported in the literature,2 the incidence of nonunion in our series is in the lower range (4.9%). We attribute the lower incidence of nonunion in our cases to the mechanobiological combination of our surgical technique, choice of implant for fixation and use of fibular strut graft. The fibular grafts helps in stability and the union of fractures. Radiographic signs of AVN 16 developed in seven patients during follow-up (Fig. 3). The incidence of AVN ranges between 0% and 67% with most reports being <15%.2 The reported incidence of AVN after valgus osteotomy with a non-vascularised graft varies from 0% to 75%.2 In a previous report of valgus intertrochanteric osteotomy in children, signs of AVN improved in three patients over 12–18 months and appeared in another after 60 weeks.1 In another report with angled blade plates, signs of AVN improved in two patients but three patients showed progression and collapse necessitating hip replacement.17 In reports where DHS fixation was used no AVN necrosis was reported.10,12 In our series, the fibular strut graft may be responsible for preventing collapse in five out of seven patients by mechanical support and/or revascularisation. All patients were evaluated preoperatively for the presence of AVN on radiographs16 only and not by MRI. We consider this as a weakness of our study. Preoperative MRI was available for five patients and MRI was not feasible in the rest due to financial constraints. Even though this is a prospective study, a randomised comparative study of two groups with or without use of a fibular graft is ideally recommended and authors believe that the absence of a randomised comparison group is a weakness of our study. Our surgical technique is reproducible with radiological union in 39 out of 41 patients and consistent excellent or good functional outcome in 85% of patients over a 32-month follow-up. We believe 208 angle of and a smaller wedge correction is necessary and sufficient as it does not stretch the capsule and has a favourable effect on capsular blood supply. Close reduction preserves the retinacular blood supply vital for fracture union. Intact blood supply from the ligamentum teres may facilitate revascularisation of both the femoral head and across the fracture in a stable mechanobiological environment provided by our technique.31 Union might be aided by bone dust from reaming by the 9 mm DHS reamer acting as an internal bone graft. Conclusion Valgus intertrochanteric osteotomy with fibular grafting is an effective procedure to achieve union in neglected femoral neck fractures in young patients less than 60 years of age. Internal fixation with DHS and double angle side plate is technically simpler. We recommend joint replacements only as a salvage procedure. Conflict of interest statement It is here by declared that none of the authors have any financial and personal relationships with other people or organisations that could inappropriately influence (bias) this work submitted for publication in your esteemed journal and that no funding or sponsorship was received for this study.
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