Keywords intertrochanteric fracture of the femur; powered hip screw; internal fixation
Femoral intertrochanteric fracture is one of the common injuries of the hip, mostly seen in the elderly, and with the aging of the population, the incidence of intertrochanteric fracture is on the rise. The femoral trochanter is rich in blood flow and has a high healing capacity after fracture. Although the fracture can be healed by non-operative treatment, it is prone to complications due to long bed rest, and thus surgical treatment is now mostly advocated. From September 2004 to October 2008, 307 cases of intertrochanteric fractures of the femur were treated with DHS in our hospital, and satisfactory results were obtained. Wang Linqing, Department of Orthopedics, Lanzhou Hospital of Traditional Chinese Medicine and Traumatology
1 Clinical data
Of the 307 cases in this group, 128 were male and 179 were female; age ranged from 47 to 92 years old, with an average of 72.8 years old; 141 were left-sided and 166 were right-sided. Causes of injury: fall while walking, car accident, fall from height, heavy object crushing, etc. The type of fracture was based on Evans-Jenson typing criteria: 46 cases of type I, 77 cases of type II, 118 cases of type III, 49 cases of type IV, and 17 cases of type V. There were 28 cases of combined heart disease, 74 cases of combined hypertension, and 57 cases of diabetes mellitus. There were 56 cases of stable type and 251 cases of unstable type. All patients were given bone traction or skin traction of the affected limbs after admission; control of medical diseases and good preoperative preparation.
2 Treatment methods
The patient was placed in a supine position with the affected hip elevated, and the perineum was supported by a padding that could be wrapped by X-ray to counteract the traction, and the patient’s lower limbs were fixed on the traction bed, and the traction was counteracted and adjusted bilaterally. The lateral femoral incision is made about 5-8 cm long, from the skin through the iliotibial bundle, the broad fascia tensor, and the lateral femoral muscle to reveal the femur about 1 cm below the greater trochanter, and in the absence of a combined small trochanter fracture, the lateral femoral periosteum is simply incised 6-8 cm below the trochanter, and the point of entry is the level of the tip of the small trochanter at the lower edge of the greater trochanter. The fracture end is about 1.0 cm from the cartilaginous surface of the femoral head, and the fluoroscopic position is selected as the guide pin that should be below the center of the femoral neck in anterior-posterior position and at the center of the femoral neck in lateral position [1], and the hole is drilled and tapped along the guide pin, and the coarse tension screw is screwed in, and a 3- to 8-hole plate is placed and fixed with pressure. For those with combined small trochanteric fracture displacement, the muscle was stripped from the upper edge of the femur, the small trochanter was repositioned by stretching and fixed with tension screws as far as possible, and for those with comminution, autologous iliac bone extraction and bone grafting was feasible, and negative pressure drainage was placed in the wound.
Postoperatively, the patient’s blood pressure, pulse, respiration, body temperature, oxygen saturation, and blood flow and sensation of both lower limbs, especially the affected limb, were detected. The main treatment is to control infection and reduce swelling, without hemostatic drugs. For those with more serious injury and surgical trauma, choose to apply low-molecular heparin calcium; for comorbidities, continue active treatment; for those with obvious osteoporosis, apply calcium and vitamin D treatment and delay bedtime appropriately. On the 2nd postoperative day, patients should be allowed to take a sitting or semi-sitting position, actively cough and excrete sputum to prevent lung infection; turn regularly to prevent decubitus ulcers; patients should actively do muscle contraction exercises to promote blood circulation and prevent deep vein thrombosis, and move the hip and knee joints in bed. For stable fracture, the patient could move down with the help of abutment after 2 weeks without weight-bearing activities, and after 3-8 weeks with partial weight-bearing activities; for unstable patients, the patient should continue to be bedridden and wear non-reversing shoes with the external booth of the affected limb for 4 weeks.
3 Results
All 307 patients in this group were followed up for 6 to 32 months, with an average of 23 months. Among them, 7 cases of compression nail cutting femoral neck and hip inversion appeared, and 2 cases of screw loosening withdrew. Hip function was based on the criteria proposed by Huang Gongyi et al [2]: excellent, no hip pain, no deformity, normal function; good, fracture healing without deformity, occasional hip discomfort, slightly affected function, not affecting life; poor, poor fracture healing, deformity, persistent pain, significantly limited function, life cannot be taken care of. In this group, there were 151 cases of excellent, 149 cases of good and 7 cases of poor, with an excellent rate of 97.72%.
4 Discussion
4.1 Treatment principles of femoral intertrochanteric fracture Femoral intertrochanteric fracture has been treated mostly by non-operative methods because of the patient’s age and many combined medical diseases. Although fracture healing was eventually obtained, it often brought more serious complications to the patients, such as decubitus ulcer, urinary tract infection, pneumonic pneumonia, hip entropion, etc., and the mortality rate was high. With the improvement of medical technology, we propose that when the patient’s general condition allows, we should try to operate early to reduce the bed rest time, facilitate early functional exercise, reduce the patient’s heart burden, reduce complications, decrease mortality and improve the patient’s quality of life.
4.2 The design of DHS is to fix the proximal end of the fracture by means of tension screws in the femoral neck, which effectively prolongs the strength of the proximal segment of the fracture fixed by the internal fixation, and the other end has a plate structure to fix the distal end of the fracture. The force acting on the femoral head can be decomposed into the inversion shear force that displaces the fracture and the compressive stress that inserts the fracture, and the DHS nail does axial movement in the sleeve, which not only has a static compressive effect but also has a dynamic compressive effect, which can The DHS nail moves axially in the sleeve, which not only has a static compression effect but also has a dynamic compression effect, which can effectively counteract the inversion shear force. It conforms to the biomechanical characteristics of the upper end of the femur, and the patient can exercise the joint muscles and get out of bed for weight-bearing activities at an early stage, which is conducive to the recovery of limb function. However, it is not effective for internal fixation when there is medial femoral cortical defect; it requires high relative integrity of the lateral cortex of the greater trochanter; postoperative compression nail cutting of the femoral neck and hip inversion is mainly seen in elderly and unstable patients, and intraoperative fracture repositioning is often difficult. Poor alignment of the medial cortex after internal fixation fails to reconstruct the supporting role of the posterior medial femoral cortex. Although the hip screw is located in the femoral neck, it can still cause rotation and displacement after bone fixation because the intertrochanteric fracture of the femur is often comminuted and has poor stability. The cutting of the bone by the nail head screw can also lead to fracture displacement. Xu Xinxiang [3] believed that internal fixation of the fracture must fix the pressure side of the fragmented bone quickly, otherwise it is easy to lead to internal fixation failure. If not fixed, the loss of support of pressure measurement during limb weight-bearing must lead to hip inversion or hip inversion with top head cutting the femoral neck. The main prevention is to restore the stability of the posterior medial femoral cortex to the greatest extent possible during surgery, and to take iliac bone implants if necessary, and to extend the weight-bearing time for unstable fractures. Emphasis on the repositioning and fixation of the lesser trochanter can also rebuild the support of the pressure side of the bone, share the compressive stress borne by the internal fixation, and prevent hip inversion. Yin Chengzhong et al [4] suggested that a tension screw should be screwed parallel to the femoral head neck through the greater trochanter above the hip screw whenever possible to strengthen its resistance to rotation. For osteoporotic patients, 1~2 cm should be retained at the end of the screw, and the screw should be screwed in an additional 5 mm. for those with obvious osteoporosis or poor surgical fixation, premature weight-bearing activities should be absolutely limited. Four of the seven patients with poor results had premature weight-bearing, resulting in hip inversion deformity. The preoperative traction repositioning reduced the operation time and bleeding; the small intraoperative incision and exposure reduced the risk of operation; the operation was less traumatic and the postoperative recovery was faster, which reduced the complications of operation and facilitated the early healing of the fracture and the recovery of hip function. This method has achieved good results in clinical practice and has been commonly used. However, there are still some complications that deserve our attention due to the patient’s age, fracture type, bone quality, surgical technique, selection of surgical indications and postoperative exercises. In conclusion, when using small incision DHS to treat intertrochanteric fractures of the femur, the indications should be mastered according to the age of the patient, the quality of the bone, and the type of the fracture, and for the elderly unstable fractures with osteoporosis, other methods of internal fixation can be considered, and postoperative functional exercises should be reasonably guided to minimize the occurrence of complications.
References
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[2] Huang GY, Wang FQ. Analysis of the efficacy of goose head nailing in the treatment of intertrochanteric fractures of the femur [J]. Chinese Journal of Orthopaedics, 1984,4(6):34-39.
[3] Xu Xinxiang, Liu Y, Li T S, et al. Several basic issues in the current treatment of internal fixation of fractures [J]. Chinese Journal of Orthopaedics, 1996,4:204.
[4] Yin C C, Cai X H, Ren J, et al. Evaluation of the efficacy of DHS in the treatment of unstable intertrochanteric fractures of the femur [J]. Journal of Bone and Joint Injury, 2003,18(4):275.