AN EVALUATION OF PREOPERATIVE CT SCANNING FOR SELECTING ADAPTIVE NAILS IN 78 CASES OF SHAFT FRACTURE
作者：CAI Ru-bin(蔡汝宾), LI Li-qun(李力群), DENG Lei(邓 磊)
单位：Department of Surgery, Beijing Emergency Medical Center, Beijing 100031
关键词：
中华创伤杂志980153 Objective To improve the quality of intramedullary nailing commonly used in the treatment of shaft fractures.
Method Self-designed preoperative CT scanning for detecting the length and shortest diameter of the intramedullary canal of bone shaft was established in 1989.
, http://www.100md.com
Results We used this technique to treat 78 cases of shaft fractures and much better results were gained than those treated with other measurements.
Conclusions It is considered that preoperative CT scanning for selecting adaptive nail is worth recommending in clinical application.
Intramedullary nailing is a common method for treating long bone fractures and has a lot of advantages. Some authors affirmed that it is the first choice for polytrauma patients1. yet, X-ray measurement usually used is not ideal. It can't give precise length and diameter of the nail needed in surgery, sometimes too long or too short and too thin or too thick, thus influencing the surgery quality and even giving rise to a intramedulary nailing failure. How to detect the precise length and diameter of the nail to be used, one of the key factors concerning the quality of surgery, remains unsolved. From 1989 to 1992, we recommended a new technique, preoperative CT scanning for selecting adaptive nails.
, http://www.100md.com
SELF-DESIGNED CT SCAN MEASUREMENT
We first suggested a new preoperative CT scan measurement in 1989. With this method, the length and diameter of the nail can be precisely measured before surgery. So that the preparation of apparatus for internal fixation has been simplified and the quality of surgery improved. The cases using intramedullary nailings reached the standard requirements without changing any other nail during surgery. Now, preoperative CT scan becomes our routine preparations before intramedullary nailing. From January 1992 to December 1993, the measurement was used in 78 cases in our hospital. The details are as follows.
, http://www.100md.com
Methods of measurement 1. Sytec 4000 systemic CT scanner of American GF company was used to measure the length and diameter of contralateral homonymous bone according to the landmarks of different bones.
The length of femur is measured from the piriform recess of the proximal femur to the upper margin of the patella. The narrowest diameter of the medullary canal is usually situated at the junction one third between the middle and proximal part of the femur (Fig.1).
, 百拇医药
The length of the tibia is measured from the middle point between the tibial plateau and tubercle to 1cm in the proximity of the distal end of tibia. The narrowest diameter of the medullary canal is usually situated at the middle or distal one third of the lower part of the tibia (Fig.2).
The length of the humerus is measured from the upper margin of the greater tuberosity with 0.5-0.7 cm of ingression to the place 1cm in proximity of the olecranon fossa of the humerus. The narrowest medullary canal is usually situated at the junction between the middle and distal third of the humerus.(Fig.3).
, 百拇医药
The measurement of proximal femur is indicated for the fracture of the base of femoral neck or trochanteric area and a Richard screw is planned to use. A line is drawn from the central area 0.5-1cm distal to the articular surface of femoral head with an angle of 130° or 140° to the longitudinal axis of femoral shaft. This line, which passes through the central axis of the femoral neck and usually meets the lateral cortex of proximal femur at 1.5-2cm below greater trochanter, is used to select adequate length and angle of the Richard screw (Fig.4).
, 百拇医药
2. While scanning, the lower limb should be in neutral position of rotation for the femur and tibia, the upper limb in supination of the forearm for the humerus, and the lower limb at 15° internal rotation to hold the femoral neck in horizontal position for hip fractures.
3. For cases of fracture of bilateral homonymous bones, the length of proximal and distal fragment should be measured separately on one side.
4. For cases of unequal length of bilateral homonymous bones, the length of proximal and distal fragment should be measured separately on the fracture side.
, 百拇医药
Data from measurements An analysis of the location, time and costs needed for scanning are shown in Table 1. Both femur and tibia are the most vulnerable to fractures. The result of one measurement can be obtained in 5 minutes. The cost for one measurement is acceptable by patients.
Data of the length and the narrowest diameter of medullary canal in different bones measured are shown in Table 2.
Table 1 The time and costs needed in CT scanning for different bones
, 百拇医药
Locations
Number of cases
Time(min.)
Cost(R.M.B)
Femur
32
2~3
50
Tibia
27
2~3
40
, 百拇医药 Humerus
12
2~3
40
Hip
7
3~5
50
Table 2 Data from CT scanning in adults
Location
Length(mm)
Narrowest diameter(mm)
, 百拇医药
male
female
male
female
Femur
360~420
320~370
8~11
7~9
Tibia
270~320
260~310
7~9
, 百拇医药
6~8
Humerus
240~280
190~240
6~8
5~7
DISCUSSION AND CONCLUSION
Ordinary measurement can't avoid errors which unavoidably influence operation quality though very careful preparation of selecting nails is done before surgery. In order to improve such situation we designed a new project for 妏recise measurements of the length and diameter of a bone and medullary canal before surgery by using CT scanning. Since then, the preoperative preparations are simplified, and the quality of internal fixation is raised to a higher level including the standard requirement of the length and diameter of the intramedullary nail. Besides, another important and significant aspect is that using preoperative CT scanning may definitely decrease the x-ray irradiation damage to the patients, particularly to a polytrauma patient. The authors believe that this project is worthy to be recommended in clinical practice.
REFERENCE
1. Cai RB, Li LQ, Evaluation of early internal fixation for fractures of the major bones in polytrauma patients. Chinese J. Traumatology 1993, 9∶17(in Chinese)
2. Browner BD, Edwards CC. The science and practice of intramedullary Nailing. Lea Febiger, Philadelphia, U.S.A, 1987; 152., 百拇医药
单位：Department of Surgery, Beijing Emergency Medical Center, Beijing 100031
关键词：
中华创伤杂志980153 Objective To improve the quality of intramedullary nailing commonly used in the treatment of shaft fractures.
Method Self-designed preoperative CT scanning for detecting the length and shortest diameter of the intramedullary canal of bone shaft was established in 1989.
, http://www.100md.com
Results We used this technique to treat 78 cases of shaft fractures and much better results were gained than those treated with other measurements.
Conclusions It is considered that preoperative CT scanning for selecting adaptive nail is worth recommending in clinical application.
Intramedullary nailing is a common method for treating long bone fractures and has a lot of advantages. Some authors affirmed that it is the first choice for polytrauma patients1. yet, X-ray measurement usually used is not ideal. It can't give precise length and diameter of the nail needed in surgery, sometimes too long or too short and too thin or too thick, thus influencing the surgery quality and even giving rise to a intramedulary nailing failure. How to detect the precise length and diameter of the nail to be used, one of the key factors concerning the quality of surgery, remains unsolved. From 1989 to 1992, we recommended a new technique, preoperative CT scanning for selecting adaptive nails.
, http://www.100md.com
SELF-DESIGNED CT SCAN MEASUREMENT
We first suggested a new preoperative CT scan measurement in 1989. With this method, the length and diameter of the nail can be precisely measured before surgery. So that the preparation of apparatus for internal fixation has been simplified and the quality of surgery improved. The cases using intramedullary nailings reached the standard requirements without changing any other nail during surgery. Now, preoperative CT scan becomes our routine preparations before intramedullary nailing. From January 1992 to December 1993, the measurement was used in 78 cases in our hospital. The details are as follows.
, http://www.100md.com
Methods of measurement 1. Sytec 4000 systemic CT scanner of American GF company was used to measure the length and diameter of contralateral homonymous bone according to the landmarks of different bones.
The length of femur is measured from the piriform recess of the proximal femur to the upper margin of the patella. The narrowest diameter of the medullary canal is usually situated at the junction one third between the middle and proximal part of the femur (Fig.1).
, 百拇医药
The length of the tibia is measured from the middle point between the tibial plateau and tubercle to 1cm in the proximity of the distal end of tibia. The narrowest diameter of the medullary canal is usually situated at the middle or distal one third of the lower part of the tibia (Fig.2).
The length of the humerus is measured from the upper margin of the greater tuberosity with 0.5-0.7 cm of ingression to the place 1cm in proximity of the olecranon fossa of the humerus. The narrowest medullary canal is usually situated at the junction between the middle and distal third of the humerus.(Fig.3).
, 百拇医药
The measurement of proximal femur is indicated for the fracture of the base of femoral neck or trochanteric area and a Richard screw is planned to use. A line is drawn from the central area 0.5-1cm distal to the articular surface of femoral head with an angle of 130° or 140° to the longitudinal axis of femoral shaft. This line, which passes through the central axis of the femoral neck and usually meets the lateral cortex of proximal femur at 1.5-2cm below greater trochanter, is used to select adequate length and angle of the Richard screw (Fig.4).
, 百拇医药
2. While scanning, the lower limb should be in neutral position of rotation for the femur and tibia, the upper limb in supination of the forearm for the humerus, and the lower limb at 15° internal rotation to hold the femoral neck in horizontal position for hip fractures.
3. For cases of fracture of bilateral homonymous bones, the length of proximal and distal fragment should be measured separately on one side.
4. For cases of unequal length of bilateral homonymous bones, the length of proximal and distal fragment should be measured separately on the fracture side.
, 百拇医药
Data from measurements An analysis of the location, time and costs needed for scanning are shown in Table 1. Both femur and tibia are the most vulnerable to fractures. The result of one measurement can be obtained in 5 minutes. The cost for one measurement is acceptable by patients.
Data of the length and the narrowest diameter of medullary canal in different bones measured are shown in Table 2.
Table 1 The time and costs needed in CT scanning for different bones
, 百拇医药
Locations
Number of cases
Time(min.)
Cost(R.M.B)
Femur
32
2~3
50
Tibia
27
2~3
40
, 百拇医药 Humerus
12
2~3
40
Hip
7
3~5
50
Table 2 Data from CT scanning in adults
Location
Length(mm)
Narrowest diameter(mm)
, 百拇医药
male
female
male
female
Femur
360~420
320~370
8~11
7~9
Tibia
270~320
260~310
7~9
, 百拇医药
6~8
Humerus
240~280
190~240
6~8
5~7
DISCUSSION AND CONCLUSION
Ordinary measurement can't avoid errors which unavoidably influence operation quality though very careful preparation of selecting nails is done before surgery. In order to improve such situation we designed a new project for 妏recise measurements of the length and diameter of a bone and medullary canal before surgery by using CT scanning. Since then, the preoperative preparations are simplified, and the quality of internal fixation is raised to a higher level including the standard requirement of the length and diameter of the intramedullary nail. Besides, another important and significant aspect is that using preoperative CT scanning may definitely decrease the x-ray irradiation damage to the patients, particularly to a polytrauma patient. The authors believe that this project is worthy to be recommended in clinical practice.
REFERENCE
1. Cai RB, Li LQ, Evaluation of early internal fixation for fractures of the major bones in polytrauma patients. Chinese J. Traumatology 1993, 9∶17(in Chinese)
2. Browner BD, Edwards CC. The science and practice of intramedullary Nailing. Lea Febiger, Philadelphia, U.S.A, 1987; 152., 百拇医药