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1 MRIMS Journal of Health Sciences 216;4(1) pissn: , eissn: Original Article A comparative study of proximal femoral nailing and dynamic hip screw in the management of inter trochanteric fracture femur 1 Dr. V. P. Raman, 2 Dr. P. Vijaya Shankar 1 Professor of Orthopedics, Malla Reddy Institute of Medical Sciences, Hyderabad 2 Consultant Orthopedic Surgeon, Srikara Hospitals, Hyderabad Corresponding Author Dr. V. P. Raman vpraman4@gmail.com Abstract: Inter-trochanteric fractures of the femur are one of the most common fractures of the hip in the elderly. They occur usually due to low energy trauma like simple falls. The incidence is rising because of increased life expectancy. The prevalence of these fractures is related to numerous factors including osteoporosis, malnutrition, decreased physical activity, impaired vision, neurological impairment and altered muscle balance. The present study was a prospective randomized study consisting of 6 adult patients with fresh inter-trochanteric fractures of the femur who were treated with DHS or PFN at MediCiti institute of Medical Sciences Ghanpur, Rangareddy District, Andhra Pradesh between June 21 and June 212. This study was carried out to compare the results of inter-trochanteric fractures treated with DHS and PFN. All the 6 patients were followed up at regular intervals. Inter-trochanteric fractures were most common between the ages of 61-7 years in our series. A trivial fall at home was most common mechanism of injury (7%). Males outnumbered females. Type 1 and 2 (Boyd and Griffin) were most common. Blood loss was less for PFN (197 ml) as compared to DHS (34 ml). There were no significant differences in the intra-operative complications with both implants. The mean time for full weight bearing was 1.75 weeks for PFN and weeks for DHS, for radiological union was weeks for PFN and 22.4 Weeks for DHS. There were more excellent/good results with PFN (93%) as compared to DHS (78%). There was one poor result with DHS and none with PFN. Limb length discrepancy (>1cm) was equal in both groups (2 each). Key words: Inter-trochanteric fractures, femur, prospective randomized study INTRODUCTION: Inter-trochanteric fractures of the femur are one of the most common fractures of the hip in the elderly. They occur usually due to low energy trauma like simple falls. The incidence of inter-trochanteric fractures is rising because of increased life expectancy. Inter-trochanteric fractures are generally more common in females than males. The prevalence of these fractures is related to numerous factors including osteoporosis, malnutrition, decreased physical activity, impaired vision, neurological impairment and altered muscle balance. In the young population intertrochanteric fractures occur due to high energy trauma. Several classifications have been proposed like Boyd and Griffin classification 1949 (1), Evan s classification 1949 (2), Jensen classification (198) (3), Kyles classification (4), Enders classification (5) and AO classification. (6) The first implant to be used with success was Fixed-angle Nail-plate (e.g., Jewett nail, Holt nail) consisting of Triflanged nail fixed to a plate at an angle between 13 degrees and 15 degrees. Although these devices provided stabilization of the femoral head & neck fragment to the femoral shaft, they did not allow fracture impaction. The experience with fixed-angle nail plate devices indicated the need for a device that allowed controlled fracture impaction. This gave rise to Sliding Nail-Plate devices. The goal of treatment in inter-trochanteric fractures is to return the patient to pre-injury levels of function without long term disability and avoiding medical complications. The Dynamic hip screw (DHS) system has become a widely used method of internal fixation and remains the gold standard against which other fixation devices need to be compared. MRIMS Journal of Health Sciences, Vol. 4, No. 1, January-March 216 Page 14

2 Intramedullary Hip Screw devices have recently been developed for stabilization of per-trochanteric fractures (Gamma nail) (7, 8). These devices couple a sliding hip screw with a locked Intramedullary nail. Proximal femoral nail (PFN) is a cephalo-medullary nail, which has two screws in the neck and two interlocking screws in the femoral shaft. However, patients treated with these devices are at increased risk for femoral shaft fracture at the nail tip and the insertion sites of the distal locking screws. MATERIAL AND METHODS The present study was a prospective randomized study consisted of 6 adult patients with fresh inter-trochanteric fractures of femur who were treated with DHS or PFN at MediCiti institute of Medical Sciences Ghanpur, Rangareddy District, Andhra Pradesh between June 21 and June 212. This study was carried out to compare the results of intertrochanteric fractures treated with DHS and PFN. All the 6 patients were followed up at regular intervals. SELECTION CRITERIA INCLUSION CRITERIA 1. All patients with fresh inter-trochanteric fractures femur. 2. Age Patients above age of 18 years. 3. Sex Both males & females were included EXCLUSION CRITERIA 1. Patients below age of 18 years. 2. Patients with old or malunited intertrochanteric fractures treated elsewhere 3. Medically unstable patients who were at poor risk for surgery. 4. Patients with any other ipsilateral fractures were also excluded. The study group was divided into two groups: Group A: fresh inter-trochanteric fractures treated with Proximal femoral nailing. Group B: fresh inter-trochanteric fractures treated with Dynamic hip screw. All the patients were evaluated for associated medical problems and were referred to repective departments where necessary. Associated injuries were evaluated and treated simultaneously. The patients were operated on elective basis after pre-anaesthetic check up. DYNAMIC HIP SCREW The implant consists of lag screw, a compression screw & barrel attached to side plate. 2. Compression Screw of 19mm allows a compression of 5mm 3. Barrel side plate in angles of 125, 13, 135, 14, degrees & from 2-12 holes mm cortical screws used to fix the side plate with shaft. In our study we used lag screw of 6-11mm and a side plate that allowed a purchase of at least 6 to 8 cortices on the shaft of femur and degrees angled plate depending upon the neck shaft determined preoperatively. PROXIMAL FEMORAL NAIL The implant consists of proximal femoral nail, self tapping 6.2mm set screw, self tapping 8mm femoral neck leg screw, 4.9mm distal locking screw. In our study we used the standard length PFN of 25mm with distal diameter of 9, 1, and 11mm in most of our cases. SURGICAL TECHINIQUE: DYNAMIC HIP SCREW PATIENT POSITIONING: Patient is positioned supine on a fracture table with a radiolucent, padded countertraction post between the injured leg and the uninjured leg which is flexed and abducted at the hip in a leg holder. The injured leg is held by a foot plate or boot attached to the other leg extension of the fracture table. The level of insertion of the guide pin varies with the angle of the plate used. The proximal aspect of the osseous insertion of the gluteus maximus and the tip of the lesser trochanter, which are approximately 2 cm below the vastus lateralis ridge, help identify the level of entry of a 135 degree angle plate. Set the triple reamer to the lag screw length indicated by the measuring gauge and ream until the aspect of the positive stop reaches the lateral cortex. Assemble the appropriate Lag screw onto the insertion wrench. Screw the Lag screw retaining rod into the distal end of the Lag screw until a firm connection is obtained. Place the entire assembly over the guide pin and introduce it into the reamed hole. Advance the Lag screw into the proximal femur to the predetermined level and verify its position with image intensification in both planes. Use plate clamp to secure the plate to the shaft. Release traction to allow impaction of the fracture fragments especially in unstable inter-trochanteric fractures. Attach the plate to the shaft of femur using 4.5 mm cortical screws. 1. Lag Screw is available in length from 6-11mm. MRIMS Journal of Health Sciences, Vol. 4, No. 1, January-March 216 Page 15

3 PROXIMAL FEMORAL NAILING Make a lateral incision, extending from the tip of the trochanter proximally for 3 to 8 cm. Insert the curved bone awl through the tip of the greater trochanter. Position the tissue protector on the tip of the trochanter, and insert a 3.2-mm tip threaded guide pin. Advanced the pin down the femoral canal well beyond the subtrochanteric region. Attach the appropriate nail to the drill guide assembly with the drill guide bolt. Insert the tip of the nail into the prepared proximal femur, and push it down the shaft. Do this under fluoroscopic control. After inserting the guide pin, remove it from the drill sleeve so that the lag screw length measurement can be correctly determined. Position the lag screw length gauge so that it rests against the guide pin and is flush with the drill sleeve. Read the length of the lag screw directly from the guide pin. Assemble a centering sleeve onto the lag screw insertion wrench. Attach the appropriate lag screw to the wrench, and tighten the lag screw. Lock the distal end of the long Intramedullary hip screw with 4.5-mm cortical screws using a 3.5-mm drill and standard freehand techniques using IITV. RESULTS Functional results were assessed based on Harris hip score. (29) In our study maximum age was 8 years and minimum age was 31 years. The mean age was years. The majority of patients were between 51-7 years of age, which constitutes 58.35% of total cases. Out of 6 patients 4 were males and 2 were females. Right side was involved more frequently than left side. Table 1: Mode of injury Mode injury of Domestic fall 42 7 Road traffic 18 3 Sport injuries Total 6 1 (%) Table 2: Type of fracture Type of fracture No (%) PFN DHS PFN DHS Type Type Type Type Total Table 3: Intraoperative complications DHS Complications Improper positioning of Richard screw Varus angulation Drill bit Breakage Guide wire breakage 5 2 Table 4: Intraoperative complications of PFN Complications Failure to achieve closed reduction Fracture of lateral cortex Failure to put derotation screw Failure to lock distally Jamming of nail Drill bit breakage Guide breakage wire 1 MRIMS Journal of Health Sciences, Vol. 4, No. 1, January-March 216 Page 16

4 All patients were followed up at 2 weeks, and later monthly till fracture union, and at 6, 9 & 12 months post operatively. Table 5: Interpretation of functional results of DHS Functional Results Excellent Good Fair Poor Table 6: Interpretation of functional results of PFN Functional Results Excellent 14 5 Good Fair Poor DISCUSSION The proximal femoral (PFN) has emerged as a viable alternative to Dynamic hip screw (DHS) in the fixation of inter-trochanteric fractures. Various studies have even found it superior to the DHS, especially when the fracture configuration is unstable. The factors which influence the stability of fixation are loss of postero-medial cortex, reverse oblique fractures, shattered lateral wall, extension into femoral neck area and poor bone quality. Gotfried (9) has describe the important lateral trochanteric wall as a key element of stability. The lateral trochanteric wall acts as a buttress to the proximal fragment. A shattered lateral wall allows for excessive collapse of the proximal fragment over the sliding screw. Excessive collapse results in pain, reduced mobility at the hip, and sometimes nonunion and implant failure. Thus it is important to preserve the lateral wall during surgery. Shen G (1) studied 63 elderly patients with trochanteric fractures who were fixed with PFN (n= 31) and DHS (n= 32). They concluded that each has advantages, but for unstable fractures PFN is ideal. Zeng C (11) conducted a meta-analysis to compare PFN with DHS in the management of trochanteric fractures. They concluded that PFN was superior to DHS in terms of duration of surgery, intra-operative blood loss, rate of fixation failure and overall complications. Gupta RK (12) reported their experience of stabilizing 74 unstable trochanteric fractures of which 46 underwent lateral wall reconstruction using trochanteric stabilizing plate (TSP) and 34 cases with intact lateral wall who had DHS with additional antirotation screw. In our study, the mean radiographic exposure was shoots (SD=12.97) for PFN and (SD=13.65) shoots for DHS (t value=9.513, P<.1). The mean duration of operation was minutes (SD=15.94) for PFN and 79 Minutes (SD=14.88) for DHS (t value = , P=.59). The mean blood loss was 197 ml (SD=45.1) for PFN and 34 ml (SD=49.32) for DHS (t value=8.176, P<.1). Our results were consistent with the results of most of the other series. CONCLUSION: The present study comprised of 6 patients of intertrochanteric fractures fixed with PFN and DHS alternatively to avoid bias (3 each). Inter-trochanteric fractures were most common between the ages of 61-7 years in our series. A trivial fall at home was most common mechanism of injury (7%). In our study, males outnumbered females probably because they were more involved in road accident (1 males vs 4 females) and also females reported late or never. Type 1 and 2 (Boyd and Griffin) were that most common in our series. Incision length was smaller for proximal femoral nail. Blood loss was less for PFN (197 ml) as compared to DHS (34 ml) (p<.1). Radiation exposure was more for PFN (78 shoots) than DHS (45 shoots) (P<.1). The mean duration of operation was 87 minutes for PFN and 79 minutes for DHS (P=.59). There were no significant differences in the intra-operative complications with both implants. The mean time for full weight bearing was 1.75 weeks for PFN and weeks for DHS (P<.1). The mean time for radiological union was weeks for PFN and 22.4 weeks for DHS, which was statistically significant (P<.1). There was no significant difference in average duration of hospital stay between the two groups. Functional results based on Harris hip score (ability to sit crossed leg, squat, absence of hip pain, independent mobility) were better with PFN. There were more excellent/good results with PFN (93%) as compared to DHS (78%). There was one poor result with DHS and none with PFN. Limb length discrepancy (>1cm) was equal in both groups (2 each). Overall, we believe that with experience, operative time and radiation exposure can be reduced in case of PFN. Thus we conclude that PFN is a better alternative to DHS in the management of inter-trochanteric fractures in terms of short term functional results but is a technically more demanding procedure and requires more expertise as compared to DHS. REFERENCES: 1. Boyd HB, Griffin LL. Classification and treatment of trochanteric fractures. Arch Surg 1949;58: Evans E. The treatment of trochanteric fractures of femur. J Bone Joint Surg 1949;191: MRIMS Journal of Health Sciences, Vol. 4, No. 1, January-March 216 Page 17

5 3. Jensen JS. Classification of trochanteric fractures. Acta Orthop scand 198;51(5): Kyle RF, Right TM. Biomechanical analysis of the sliding characteristics of compression screws. J Bone Joint Surg 198;62-A: Enders HG. Treatment of peri trochanteric and sub trochanteric fractures of femur with Enders pins in the hip, St Louis, 1978 Mosby Elsevier 6. Orthopedic Trauma Association Committee for coding and classification of fracture and dislocation compendium. J Orthop Trauma 1996;11: Bong MR, Patel V, Lesaka K, Eqol KA, Kummer FJ, Koval KJ. Comparison of a sliding screw with a trochanteric lateral support plate to an intramedullary hip screw for fixation of unstable intertrochanteric hip fractures: A cadaver study. J Trauma 24;56(4): Docquiet PL, Manche E, Actrique JC, Genletb B. Complications associated with gamma nailing: A review of 439 cases. Acta Orthop Belg 22;68(3): Gotfried Y. The lateral trochanteric wall. Clin Orthop 24;425: Shen G. Effectiveness comparison of proximal nail antirotation and dynamic hip screw for inter trochanteric fractures in the elderly. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 212;26(6): Zeng C, Wang YR, Wei J, Gao SG, Zhang FJ, Sun ZQ et al. Treatment of trochanteric fractures with proximal femoral anterotation or dynamic hip screw: A meta analysis. J Int Med Res 212;4(3): Gupta RK, Sangwan K, Kamboj P, Punia SS, Walecha P. Unstable trochanteric fractures: the rold of lateral wall reconstruction. Int Orthop. 21;34(1): Cite this article as: Raman VP, Vijaya Shankar P. A comparative study of proximal femoral nailing and dynamic hip screw in the management of inter trochanteric fracture femur. MRIMS J Health Sciences 216;4(1): Source of Support: Nil. Conflict of Interest: None. MRIMS Journal of Health Sciences, Vol. 4, No. 1, January-March 216 Page 18