![[BHJ LOGO]](../../images/sp_bhjpan.gif) |
       |
|
|
BIOLOGICAL PLATING OF COMMINUTED FEMORAL FRACTURES
Nirad S Vengsarkar*, Ab Goregaonkar***
*Lecturer; **Professor and Head of Unit; Department of Orthopaedics, LTMGH and LTMMC, Sion.
Comminuted diaphysio-metaphyseal fractures of the femur were treated with the slide plate principle using the dynamic compression screw/plate or the condylar buttress plate and were followed up for a period of one year on the average.The rate of union seen was fast using this technique with radiologically demonstrable callus seen as early as three to four weeks with good patient compliance and return to function. We concluded that biological plating in comminuted fractures of the femur gives good results in cases where it is impractical to obtain an anatomical reduction.
INTRODUCTION
Open reduction with internal fixation using a plate is occasionally used in comminuted fractures of the diaphysio-metaphyseal junction of the femur.
A plate when used in this manner especially with large screw fixation of the individual fracture fragments would result in their devitalisation. [8] , [9] In sliding plate principle every attempt is made to maintain all the soft tissue attachments and blood supply of the intervening comminuted fragments since union will depend primarily on the formation of the bridging callus rather than primary bone union. [2] , [3] , [6] , [7]
Length axial and rotational alignment have to be corrected and the fracture zone stabilized to allow union. It is the rapid integration of the unreduced but well aligned vital fragments into the fracture callus, which buttresses the fracture area opposite the plate reducing the risk for overload and fatigue failure of the implant. [1] , [15]
MATERIAL AND METHODS
Twenty patients who were admitted into our institution following vehicular or railway accidents were followed up for an average period of one year.
The patients were in the following age groups;
< 20 years - 2 20-40 years - 8 40-60 years - 6 > 60 years - 4
Thirteen male and seven females were included in this study.
The location of the fractures was as follows: [11]
Supracondylar region : - 8 Subtrochanteric region : - 12
Comminuted midshaft fractures were not included in this study.
Nature of comminution was guided by Winquist classification of femoral fractures dividing them into four grades of comminution.
The patients were evaluated for range of movement of the knee/hip; for patient comfort; for radiological evidence of callus formation and for complications - both early and delayed.
OPERATIVE TECHNIQUE
The preoperative planning involves determination of the approximate size of the plate required for fracture stabilizing assuming four holed purchase is required on the intact femur away from the fracture site.
Here we shall discuss the operative technique for a supracondylar fractures.
The patient is taken on a radiolucent table with arrangements to give traction to the limb and to control rotational alignment or the patient can also be put on a standard table with an assistant used to give traction and control the rotations.
Incision is taken on the condyle or trochanter.
Lateral approach is used. The incision is then placed close to the joint near the fracture so that it is possible to enter the dynamic condylar screw along with fixation of the intra articular extension of the fracture. The correct screw positioning is checked with radiographs.
Once the screw position and length have been accepted, an incision is taken on the skin proximally near the comminuted fracture, so that an intact bridge of skin is maintained between the two incisions. The pre-operatively determined plate is selected and is reversed, so that the barrel faces out and then slipped under the vastus lateralis muscles close to the bone as possible. The passage of the plate close to bone along with the appropriateness of the length and varus / valgus angulation are then checked on radiographs. If the position of the plate is acceptable, the plate is then turned so as to seat the barrel into the screw and the plate is then fixed to the bone. Posterior sag of the proximal fragment is corrected with traction and placement of Hohmann’s spikes before affixing the plate. Thetwo incisions are closed separately. [13-15]
This rotation flexibility is what makes this fixation easier than the condylar blade plate system.
Rotational alignment is checked by the "cable technique" - a cautery wire is used to check that the centre of the head of femur, knee and ankle lie in the same line.
Length is checked by confirming the length obtained after traction with that of the opposite limb. It is roughly determined from the tip of the greater trochanter to the lateral joint line. [6,7]
POST OPERATIVE PERIOD
Post-operatively the patients are placed initially on static and dynamic quadriceps exercises and continues passive motion as the patient can tolerate.
Patient is kept on nonweight bearing mobilization till around six weeks when partial weight bearing is allowed. The patient usually progresses to full weight bearing by the third or fourth month. [5]
COMPLICATIONS
Intraoperative
1.Failure to get correct reduction in length and to correct the sagging of the fragments.
2.Plate does not seat adequately specially if not inserted in the correct plane or rotation of fragments is not corrected.RESULTS
We studied 20 patients at our institution who had supracondylar and subtrochanteric fractures and who were in the age group of 18 to 60 years.
The patients were followed up for an average period of one year.
The patients were studied according to the :
1.Range of movement obtained at the knee and hip.
2.X-ray evaluation of callus formation.
3.Possible complications - shortening / malrotation / secondary collapse into varus etc. [10]We found the return of function of the knee and hip depended on the proximity of the fracture to the joint. The fractures with intra-articular extension took a longer period to recover as compared to the extra articular ones with the average period being five weeks. The patients were started on the continuous passive motion machine on day three or four and graduated to dynamic quadriceps exercises.
We found that the average appearance of callus seen radiologically was between four and five weeks after surgery with more callus being seen in the fractures with more comminution and hence less surgical interference. The callus generally showed a linear increase with time and good union was seen at an average period of three to four months post operatively. [4] , [5]
In our series no patient needed bone grafting as a secondary procedure for delayed union. Complications included infection in one patient. This infection was seen immediately post-op and was controlled with wound wash and use of appropriate antibiotics. This fracture then went on to union in a period of approximately four months.
Shortening of 1 cm was seen in three patients, but these patients could compensate well and went on to have good function.
There was only one case that had some element of malrotation (external rotation). This was about 15 degrees. The patellar tracking was however normal and the patient went on to have good function. seen in our study. This was probably the result of delaying the weight bearing to such a time so as to allow the medial bony buttress to develop. [2] , [7]
The average duration of surgery in our series was two to two and half-hours, with the average blood loss being 200 ml in the subtrochanteric group. In the supracondylar fracture group we used the tourniquet where possible to minimize the blood loss.
DISCUSSION
Despite the belief that soft tissues should be preserved during the open reduction of fractures, surgeons traditionally have sought to achieve maximum stability regardless of the impact it might have on the soft tissues. [13]
This traditional approach is responsible for many of the problems for which plating was condemned and later abandoned for certain fractures. The conflict between the need for absolute anatomical reduction and the desire for soft tissue preservation is analogous to saying "wash me but do not wet me". [16]
Baumgaartel et al [3] have demonstrated that indirect reduction and bridge plating was superior to direct fragment reduction and anatomical fixation in respect to radiology, biomechanics and microangiography. He showed faster gap filling and callus beginning in the second or third week in indirect and in the sixth week in direct reduction.
Tenar et al17 showed that plate devices reached 50 per cent of the torsional stiffness of an intact femur whereas intramedullary implants reached only 5 per cent.
It was also noticed that intramedullary locked rods supported higher combined bending and compression forces compared to plates.
Slide plate is used particularly in patients with fracture lines extending close to the joint or with intra-articular extensions in which case an intramedullary nail cannot be used. Mohammed et al [12] found that screw plate devices partially unloaded the medial cortex and loaded the lateral femur with tensile forces.
Minimally invasive plate osteosynthesis does not make bone grafting unnecessary, but reduces the rate considerably compared to conventional plating in complex and long fractures. In our series no patient received bone graft. [2]
Stress is also distributed over a large area of plate which is without screws therefore fatigue failure of the implant can be expected later so more time should be allowed for the biological buttress to develop.
Important features in this mode of treatment are obtaining length, rotational alignment, angulation correction and placing the plate in the correct plane as close to the bone to permit biological union.
The average reported blood loss with this method in literature is 740 ml with the average duration of surgery being two hours. [6]
In conclusion we find biological plating a technically easy procedure to master with the use of a conventional implant, with radiography not being mandatory and especially useful in comminuted
fractures with intra-articular extensions.
REFERENCES
1. Bolhofner Br, Carmen B, Clifford P. The results of open reduction and internal fixation of distal femur fractures using a biological (indirect) reduction technique. J Orthop Trauma 1996; 10 : ((372-37.?))
2.Krettek C, Schandelmaier P, Miclau T, et al. Minimally invasive plate osteosynthesis (MIPPO) using DCS in proximal and distal femoral fractures. Injury 1998; 29 (3).
3.Baumgaertel F, Bull M, Rahn A. Fracture healing in biological plate osteosynthesis. Injury 1998; 29 (3).
4.Gerber C, Mast JW, Ganz R. Biological internal fixation of fractures. Arch Orthop Trauma Surg 1990; 109 : 295-303.
5. Heitemeye U, Kemper F, Hierholzer G, et al. Severely comminuted femoral shaft fractures; Treatment by bridging plate osteosynthesis. Arch Orthop Trauma Surg 1987; 106 : 327-30.
6. Wenda K, Runkel M, Degreif J. Minimally invasive plate fixation in femoral shaft fractures. Injury 1997; 28 (1) : S-A13-S-A19.
7. Sieberrock KA, Muller U, Ganz R. Indirect reduction with a condylar blade plate for osteosynthesis of subtrochanteric femoral fractures. Injury 1998; 29 (3).
8. Kinaste, Bolhofner BR, Mast JW, Ganz R. Subtroch fractures of the femur. Results of treatment with the 95 degree condylar blade plate. Clin Orthop 1989; 238 : 122-30.
9.Kyle RF. Fractures of the proximal part of the femur. J Bone Joint Surg 1994; 76-A : 924.
10.Neer CS, Grantham SA, Shelton ML. Supracondylar fractures of the adult femur. A study of 110 cases. J Bone Joint Surg Am 1967; 49 : 591-613.
11.Mize RD, Bucholz RW, Grogen DP. Surgical treatment of displaced comminuted fractures of the distal end of the femur. J Bone Joint Surgery Am 1982; 64 : 871-8.
12.Mohammed N, Harrington I, Kellar J, et al. Biomechanical analysis of gamma nail and sliding hip screw. Clin Orthop 1994; 304 : 280.
13.Muller ME, Allgower M, Willenger H. Manual of internal fixation. 3rd edition Berlin : Springer - Verlag, 1991.
14.Olerud S. Operative treatment of supracondylar fractures of the femur. JBJS Am 1972; 54 : 1015-32.
15.Ostrum RF, Geel C. Indirect reduction and internal fixation of supracondylar femur fractures without bone graft. J Orthop Trauma 1995; 278-84.
16.Perren SM. The concept of biological plating using the limited contact dynamic compression plate. Scientific background design and application. Inquiry 1991; (suppl) : 1-41.
17.Tenar M, Martin RE. The evolution of modern plate osteosynthesis. Injury 1997; 29 (suppl no. 1).
 |