A comparative study of 30 cases of trochanteric fracture femur treated with dynamic hip screw and proximal femoral nailing

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1 Original Article A comparative study of 30 cases of trochanteric fracture femur treated with dynamic hip screw and proximal femoral nailing Jaswinder Pal Singh Walia *, Himanshu Tailor**, H S Mann ***, Avinash Chander Gupta****, Jagdeep Singh Rehncy *****, Sargun Singh*****, *Professor & Head, ** Junior Resident, *** Associate Professor, ****Professor, *****Senior Resident, *****Undergraduate Department of Orthopaedics Government Medical College, Patiala, Punjab ABSTRACT Trochanteric fracture femur is a common and grievous injury, mostly suffered in elderly people. In young people it is mostly an outcome of high energy trauma. Various procedures of internal fixation has been proposed as a treatment. Present study was a prospective evaluation and comparison. Thirty patients(less than 65 years old) with Trochanteric fracture femur were treated with osteosynthesis with Dynamic hip screw (DHS) and Proximal femoral nailing (PFN). The clinical results were compared between the Dynamic Hip Screw and Proximal Femoral Nailing groups of 15 patients each. Keywords: Trochanteric fracture femur, Dynamic hip screw (DHS), Proximal femoral nailing (PFN) INTRODUCTION Operative treatment for hip fractures was introduced in the 1950s with the expectation of improved functional outcome and a reduction of the complications associated with immobilisation and prolonged bed rest. 1,2 Since then a variety of different implants had been used either extramedullary or intramedullary in nature.treatment options for hip fracture patients depend on the location and pattern of the fracture. For many years, the sliding hip screw and plate had been the gold standard in treating pertrochanteric fractures. Nowadays, there is an increasing interest in intramedullary nailing. Intramedullary devices, although technically difficult seems to have a biomechanical advantage over laterally fixed side plates. Biological advantage includes close reduction, less soft tissue dissection and comparatively less blood loss. Intramedullary devices such as proximal femoral nail (PFN), are more stable under loading with a shorter lever arm, so the Corresponding Author : Dr. JPS Walia, Professor and Head, Department of Orthopaedics, Govt. Medical College, Patiala, Punjab drjpswalia@gmail.com distance between the hip joint and the nail is reduced compared with that for a plate, thus diminishing the deforming forces across the implant. These are load sharing devices; so early weight bearing can be allowed. The biomechanical advantage of intramedullary devices is important particularly in unstable trochanteric and subtrochanteric fractures. 3,4 Numerous variations of intramedullary nails have been devised to achieve a stable fixation and early mobilization. Among these proximal femoral nail devised by AO/ASIF group in 1996 with anti-rotation hip pin, smaller diameter, fluting of tip and smaller valgus angles seems to be a promising implant in trochanteric and subtrochanteric fractures. MATERIAL AND METHODS The present study was conducted on 30 cases of trochanteric fractures femur below the age of 65 years. Patients were divided into two groups of 15 patients each. The first group was managed with Dynamic hip screw while second group was treated with Proximal femoral nail. Patients were given first aid in the form of skin traction, analgesics, stitching of wound, if any and appropriate antibiotics. Patients were given tetanus immunoprophylaxsis and shock, if present, was treated. Radiographic examination was done to assess the type, pattern, extent and displacement of fracture. 6

2 Walia et al Table 1 Showing Mobility in unstable I/T Fractures Mobility in unstable I/T Fractures Mobility At 3 months Mobility At 6 months Mobility PFN DHS PFN DHS No % No % No % No % No Aide Stick Walking Frame Wheel Chair Total Table 2 Showing Complications in unstable I/T Fractures Complications In Unstable I/T Fractures PFN DHS No. % No. % Malunion Femur shortening (>1cm) Hip Pain Loss of flexion at Hip(>10deg) Superficial infection Deep infection Screw cut-out Table 3 Showing Merle d' Aubigne and Postal hip rating system for Unstable I/T Fractures Merle d' Aubigne and Postal hip rating PFN DHS system for Unstable I/T Fractures No. % No. % Malunion Femur shortening (>1cm) Hip Pain Loss of flexion at Hip(>10deg) Superficial infection Deep infection Screw cut-out Results were evaluated as per Merle d Aubigne and Postal hip rating score. SURGICAL TECHNIQUES For DHS, A 6 cm to 8 cm long incision was made along the top outer side of the femur bone taking lateral approach. Under the X-ray guidance or C-arm, the procedure was visualized on television screens. A guide wire was inserted into the head of femur. Reaming of the femur was done with power combination reamer. Tapping of the femoral head was done with lag screw tap if needed. A suitably sized lag screw was inserted and position was verified with image intensification. This was connected to a mechanical plate held in place by screws. For PFN, Reduction was achieved by closed manipulation and traction under anaesthesia. The fracture site was exposed only if reduction by closed means is not successful. The fixation used an intramedullary nail (10 11 mm in diameter), a lag screw ( mm in length), and a hip pin (10 15 mm shorter than the lag screw). The lag screw was inserted near the subchondral 7

3 Trochanteric fracture femur treated with dynamic hip screw and proximal femoral nailing femoral head. The intramedullary nail was interlocked distally with one or 2 screws. RESULTS Maximum no of patients were in the age group more than 50 years (Mean age = 52.1 years) with female to male ratio of 1.5:1 and mode of injury simple fall in majority. Mean duration of surgery for PFN was 62.6 mins and for DHS was 66 mins. Average amount of blood loss was ml in PFN group and 464 ml in DHS group. Mean for starting partial weight bearing was at 6 weeks in all the patients of unstable I/T fracture treated with PFN, while 8.44 weeks in DHS group. Mean for starting full weight bearing in unstable I/T fracture was weeks in PFN group and 13.5 weeks in DHS group (Excluding 1 case of nonunion). In all cases of stable I/T fractures treated with PFN and DHS, partial weight bearing started at 4 weeks and full weight bearing at 10 weeks. Mean for radiological union was weeks for PFN group and 13.5 weeks for DHS group (Excluding 1 case of non-union) in unstable I/T Fractures. All cases of stable I/T fractures treated with PFN and DHS showed radiological signs of union at 10 weeks (Fig 1 to 4). All patients of stable I/T fractures were using no aides for mobility at the end of 3 months and 6 months. Non-union occurred in 1 patient of unstable I/T treated with DHS, rest all fractures united. No complications occurred in patients with stable I/T fractures. All complications occurred in unstable I/T group. Out of total 15 cases of PFN, Greater trochanter fracture occurred in 1 case, difficulty in proximal locking occurred in 2 cases, difficulty in distal locking in 1 case, difficulty in reduction in 2 cases, Z-effect, reverse Z-effect was not reported in any case. All patients of stable I/T fracture had excellent functional outcome treated with PFN and DHS. DISCUSSION The need for internal fixation and early mobilisation of patients with trochanteric fractures of the femur is generally accepted, not only to reduce the morbidity/mortality rates associated with prolonged immobilisation, but also to improve the functional result through avoiding malunion and encouraging mobility. The best treatment for these fractures remains controversial. Various studies are being conducted and literature published to compare the intramedullary and extramedullary devices in the treatment of these fractures but controversy still exists. Intramedullary devices have some theoretical advantages over the DHS, as they do not depend on screw fixation of a plate to the lateral cortex, which can be a problem in very osteoporotic bone. In addition they have a shorter moment arm, because the load is transmitted to the femur along a more Dynamic Hip Screw (DHS) Fig1. Pre Op X-ray Fig 2. Post Op X-ray Of DHS 8

4 Walia et al Proximal Femoral Nailing (PFN) Fig 3. Pre Op Xray medial axis. Initially devised intramedullary devices such as gamma nail have a significantly increased risk of fracture at the tip of nail and other technical complications. Keeping in view these things, this study was conducted to compare the results of PFN and DHS in extracapsular proximal femoral fractures. Majority of the patients with intertrochanteric fracture were elderly females with history of simple fall. Cummings SR et al 5, Wallace WA et al 2 et al told that Intertrochanteric fractures constitute one of the commonest fractures of the hip. They mainly occur in elderly people with osteoporotic bone usually due to low energy trauma like simple fall. Mean duration of surgery for PFN and DHS was almost similar but amount of blood loss was more in DHS group. Ishrat A. Khan et al (2004) 6 compared the outcome of PFN and DHS fixation of unstable proximal femoral fractures in 70 patients. Operation duration was similar in two groups although blood loss was significantly low in PFN group (PFN-200 mls, DHS: 375 mls). Partial weight bearing was started earlier in PFN group than DHS droup. Full weight bearing was started in all cases only after radiological union. Radiological union occurred earlier in patients of PFN. Khaled Issaet al 7 showed similar results in his study. Average healing time was 14 weeks with using DHS, and 12 weeks with using PFN in unstable trochanteric fractures. Fig 4. Post Op Xray of PFN Non-union occurred in 1 patient (11.1%) in unstable I/T fracture treated with DHS. Although DHS is most widely used implant, the average fixation failure rate is about 10% in unstable intertrochanteric fractures (Karl Lunsjo etal 8 ). Mobility of the patients was better in cases treated with PFN; particularly in unstable I/T fracture group. Ishrat A. Khan et al (2004) 6 also showed follow up mobility was better in PFN group at 3 months. Complications such as non-union, malunion, hip pain, femur shortening were slightly higher in DHS group. Although PFN seems out to be a better implant in patients with unstable I/T fractures but it is technically difficult to apply. Out of 15 patients treated with PFN, technical difficulties occurred in 5 cases. Functional outcome was assessed using Merle d 9

5 Trochanteric fracture femur treated with dynamic hip screw and proximal femoral nailing AubigneAnd Postal Hip Rating System at 6 months after surgery. All the patients of stable I/T fractures had excellent results. Functional outcome was definitely better in cases of unstable I/T fractures treated with PFN. CONCLUSION We conclude that extracapsular proximal femoral fractures, particularly unstable intertrochanteric fractures can be better and more effectively treated with Proximal Femoral Nail despite some technical difficulties. Patients with unstable intertrochanteric fractures treated with PFN had earlier radiological union, better functional outcome less complications and earlier weight bearing. REFERENCES 1. Massive WK. Fracture of hip bone joint surgery 1964; 46a: Hugh WL. A self adjusting nail plate for fracture about hip Joint,J bone joint surgery 1955; 37A: Sermon A, Broos PLO. The use of PFNA in treatment of intertrochanteric fractures. Folia Traumatologica 2007: ActaorthopaedicaBelgica 2004 vol page Sudhir S Babhulkar. Management of trochanteric fracture. I J O Oct 2006; 40(4) : Cummings SR, Rubin SM, Black D. The future of hip fractures in the United States: Numbers, costs, and potential effects of postmenopausal estrogen. ClinOrthop 1990; 252: Ishrat A. Khan. O1013 To Nail or to Screw?. J of Bone and Joint surgery- British vol 2004, 86-B, Issue SuppIII: Khaled Issa, Ayman Khalil, Weam Mossa. Trochanteric fractures, the best method of treatment,tanta Med. Sc. J 2008; 3(2): Karl Lunsjo. Extramedullary fixation of 569 unstable intertrochanteric fractures: A randomized multicentre trial of the Medoff sliding plate versus three other screw-plate systems. Acta Orthopaedica;72(2):