EXPERIENCE WITH MANAGING COMPLICATED FRACTURES USING ILIZAROV PRINCIPLE IN LAGOS, NIGERIA

Abstract

Background

Management of complicated bone fractures in our environment is very challenging. The Ilizarov principle has been found to be a viable management option worldwide, but the use of this method in our environment has been sparsely reported.

Aim

To document our use of Ilizarov method to manage patients with complicated long bone fractures and the outcome.

Design of study

Prospective observational study.

Setting

Lagos State University Teaching Hospital, Ikeja, Nigeria.

Methodology

All the patients were treated between June 2009 and December 2012 using the Linear Rail-fixator System (LRS) according to Ilizarov principle. They were followed up for at least two years and data on demography, indications, procedure and outcome were collected and subjected to statistical analysis.

Results

Thirty patients whose procedures had been concluded were recruited. The age range was 4 - 57 years with a mean of 38 years ; 17 were male while 13 were female with a male/female ratio of 1.3:1. Specific indications for treatment included infected non-union, failed implant with limb length discrepancy and mal-union. They all had bone defects ranging from 4cm to 12cm and the pre-operative period of morbidity ranged from 2 months to 8 years. Seventeen patients had acute docking and lengthening, 10 had bone transport while 3 had simple limb lengthening. Using the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria, bone outcome was excellent in 7 patients, good in 20 and poor in 3. Functional outcome was excellent in 8, good in 19 and poor in 3. Complications included pin site infection (grades I & II) in 14 patients, knee stiffness in 6 and regenerate fracture in 1.

Conclusion

Ilizarov surgery is a good method of limb reconstruction in our environment. Our major complications are the high rate of pin site infection and knee stiffness. Good pin site care and early physiotherapy is essential.

Introduction

Long bone fractures are almost always due to high energy injuries. This may be from motor vehicular crash, firearms and falls amongst others1. No age group is immune from this but trauma is generally more prevalent in the young and active. Throughout the world, trauma is a leading cause of death and disability for all age groups except persons older than 60 years and is one of the top three causes of death for persons between 5 and 44 years2.

Several factors are responsible for the development of complications, including the trauma itself, open or closed injuries, management option offered and choice of fixation implant. Patient factors such as alcohol consumption and early weight bearing against medical advice are other factors which may cause complications3,3. Infections, which may result from some of the above factors is also a major complication which may affect the management options available5.

Management of complicated fractures has always been a challenge to orthopaedic surgeons especially in the resource challenged countries. Where resources are available, orthopaedic surgeons have the options of choosing vascularised bone transfers, bone transport, allogenic bone graft, bone graft substitutes and several other means1. Ilizarov surgery has gradually gained prominence as more surgeons acquire the skill as the device becomes more readily available and affordable.

Distraction osteogenesis(callotaxis), popularised by Ilizarov, hitherto an infrequently performed procedure has become a regular procedure today6.

Under controlled mechanical conditions, an osteotomy that is distracted will produce bone between the distracted ends: this is referred to as osteogenesis. Simultaneous histiogenesis also occurs in the surrounding soft tissues.

Earlier procedures were performed using the Ilizarov frame which is a bulky, heavy device but other less bulky, cheaper devices requiring shorter learning curves such as the Linear Rail System (LRS) are now being used. Apart from correcting limb length discrepancy with lengthening, the procedure has been adapted and used to correct various forms of deformities both congenital and acquired. Such deformities include those from complicated fractures.

Soft tissue loss with multiple sinuses, osteomyelitis, osteopenia, complex deformities with limb length inequality, stiffness of the adjacent joint, polybacterial multi-drug resistant infection and smoking all complicate treatment and recovery3,7,8,9.

Brinker10 defines non-union as a fracture that, according to the treating physician, has no possibility of healing without further intervention. He further posited that all available definitions of non-union and delayed union including one by the Food and Drug Administration (FDA) of USA and another by Muller, are inconsistent, subjective, ambiguous and arbitrary and therefore do not have any objective criteria. For example, several months of observation should not be required to declare a tibia shaft fracture with 10cm of segmental loss a non-union. According to Struijs et al7, infected non-union is defined as a state of failure of union and persistence of infection at the fracture site for 6 to 8 months. Infected non-unions of the long bones present a great challenge to the orthopaedic surgeon in providing optimal treatment of this entity. This is because treatment of infected non-unions, particularly those that have had failed multiple attempts at internal fixation or have significant deformity is complex8,9.

Limb length discrepancy (LLD) is another significant complication of long bone fractures. A difference in the length of the upper and lower limbs is not uncommon in the population. When the difference is obvious, especially in the lower limbs, it affects, not only the gait of the person, it also disturbs the whole lower limb biomechanics. It may also be a cause of lower back pain, hip and knee pain.

Lower limb LLD greater than 3cm requires surgical lengthening of the shorter limb. It should be noted that the treatment of LLD requires months, even years, for completion and requires patience and full co-operation of the patient as well as the family10.

Since the end of the last century, a large number of surgical techniques for limb lengthening have been proposed but none has successfully solved the complex problems associated with limb segment elongation. However, the Ilizarov method appears to be the most beneficial11.

It is said that living tissues subjected to slow steady traction becomes metabolically activated in both the biosynthetic and proliferative cellular pathways: this is referred to as the law of tension-stress10. Proper application of this principle combined with surgical techniques that limit trauma to bone and soft tissues can be used to lengthen all the segments of both upper and lower limbs11. Pin tract infection is graded by Paley as: Grade I which is soft tissue inflammation: Grade II which is soft tissue infection and Grade III which is bone infection1,12,13.

Over the years we have used this procedure and this study aims to share our experience in the management of complicated fractures using distraction osteogenesis. The challenges and complications encountered over this period would also be highlighted and discussed.

PATIENTS AND METHODS

This is a prospective study of patients who required lower limb reconstruction following injuries sustained from motor vehicle crashes and gunshots as well as those with post traumatic growth disorders undertaken in our hospital between 2009 and 2012. Approval for the study was sought and obtained from the ethics committee of the hospital. Only the patients treated using the Linear Rail System(LRS) manufactured by S. H. Pitkar Orthotools Pvt Ltd(www.pitkar.com) of Pune, India were included in the study. The LRS functions according to Ilizarov principle and is composed of a rail made of stainless steel painted black, 6.5mm stainless steel tapered pins, end and central clamps and a compression-distraction (CD) unit. The rails come in different lengths (200, 300 and 400mm), and the pins in different lengths of 150mm, 170mm and 200 mm. Paediatric LRS is also available for children. (Fig. 1)

Fig. 1. Linear Rail System (LRS).

Clinical diagnosis of our patients included infected non-union, failed internal fixation with non-union and limb length discrepancy, bone necrosis and gap non-union. Treatment was either simple bone elongation, acute docking and elongation and bone transport. Excluded were patients with pathological fractures, metabolic bone disease and poor bone stock.

The limb deformities were assessed pre-operatively, noting the skin condition including ulcers and sinuses, limb length discrepancies, angular deformities, bone gaps, range of joint motion and evidence of osteomyelitis. Full length plain radiographs and clinical photographs were used for assessment. Pre-operative investigations for fitness for surgery and anaesthesia were carried out as was a pre-operative review by the anaesthetists. Informed consent for surgery was obtained from the patients, who were adequately counselled with regards to the usually very lengthy duration of treatment and the need for proper pin-site and wound care. Pre-operative physiotherapy was carried out to strengthen the muscles, improve joint range of motion and to teach non-weight-bearing crutch walking.

All the procedures were carried out under spinal anaesthesia with the exception of children who had general anaesthesia. The pins were inserted in the safe corridors of the thigh (lateral intermuscular septum) and the leg (subcutaneous antero-medial border). Intra-operative imaging was used to guide pin insertion and osteotomy.

Sub-periosteal low energy osteotomy was performed after pre-drilling the cortex and bone lengthening was carried out by gradual distraction of the osteotomy site at the rate of 1mm (0.25mm four times daily), commenced ten days after osteotomy. For bone transport, a segment of bone was gradually transported within a soft tissue envelope to the other side of the bone gap (docking site).

The patients were discharged two weeks after surgery, having learnt how to use the device for distraction and to care for the pin-sites. They were ambulated non-weight-bearing with axillary crutches and seen at 2-week intervals for the first 3 visits and at monthly intervals thereafter. The follow up period of the patients was between 2 and 3 years At each follow-up visit, the following were observed: distance moved by the Compression-Distraction (CD) unit, active and passive range of motion of adjacent joints, sensation and power of muscle groups, pin site care and general hygiene, checking and tightening of loose bolts to ensure the stability of the device and limb measurements. Radiographs to assess distraction, alignment and quality of regenerate bone were taken monthly. Accurate antero-posterior and lateral views require proper limb positioning, so x-rays were supervised by the authors.

Biographic data, pre-operative diagnosis, indications for surgery, limb deformities, procedures performed, complications and outcome were documented and analysed using Microsoft excel software 2007 and presented in simple tables. Pin tract infection was graded using the Paley classification and outcome was assessed according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria 14.

Results

Thirty patients whose procedures had been concluded were recruited into the study. The youngest was 4 years old while the oldest was 57years old with a mean age of 38years. Forty percent (40%) of the patients were in the 31-40 years age group (Table 1). There were 17 males and 13 females giving a male: female ratio of 1.3:1 (Fig. 2).

Table 1. Age distribution of the patients.

AGE (YEARS)	FREQUENCY	PERCENTAGE
0-10	1	3.33
11-20	1	3.33
21-30	5	16.67
31-40	12	40
41-50	9	30
51-60	2	6.67
TOTAL	30	100

Fig. 2. Gender distribution of patients.

Motor vehicular crash accounted for 80% of the injuries sustained by these patients while 4 patients (13.3%) sustained gun-shot injuries (Fig. 3).

Fig. 3. Mechanism of Injury.

In terms of diagnosis, 10 patients (33.3%) had infected non-union, 7 patients (23.3%) had failed implant with aseptic non-union and associated limb length discrepancy (LLD) Five patients (16.7%) had open comminuted fractures and bone necrosis, five (16.7%) had mal-union with LLD, two (6.7%) had aseptic non-union with LLD in the absence of an implant and one (3.3%) had segmental bone loss at the scene of the crash (Table 2).

Table 2. INDICATIONS FOR SURGERY.

DIAGNOSIS	FREQUENCY	PERCENTAGE
INFECTED NON-UNION	10	33.3
FAILED IMPLANT WITH NON-UNION AND LIMBLENGTH DISCREPANCY	7	23.33
OPEN COMMUNITEDFRACTURE WITH BONENECROSIS	5	16.67
MALUNION WITH LIMBLENGTH DISCREPANCY	5	16.67
SEGMENTAL BONE LOSS	1	3.33
ASEPTIC NON-UNIONWITH LIMB LENGTH DISCREPANCY	2	6.67
TOTAL	30	100

The period of morbidity before treatment ranged from 3 weeks to 8 years. All the bones affected were lower limb bones with the tibia accounting for 56.7% (17 patients) and the femur, 43.3% (13 patients). The bony defects ranged between 4cm and 12cm.

The procedures that were performed in these patients included acute docking and elongation (17 patients), bone transport (10 patients) and simple elongation (3 patients). (Fig. 3-Fig. 8) The device remained fixed to the bone for periods between 9 and 20 months.

Fig. 8. After removal of LRS.

Outcome assessment using the ASAMI method revealed 7 excellent, 20 good and 3 poor bone outcome and 8 excellent 19 good and 3 poor functional outcome (Fig. 5).

Fig. 5. Outcome of management using ASAMI Classification.

Complications noted were pin site infection Paley grade I in 6 patients and grade II in 8 patients (46.7%), knee stiffness in 6 and regenerate fracture in 1. All the patients who had knee stiffness had surgery on the femur. The patient with the regenerate fracture had surgery on the femur and presented to us following a fall several months after she had started full weight bearing ambulation. She subsequently had a repeat procedure done.

Discussion

More than half of our patients were aged between 21 and 40 years and there were more males than females. This is the common age range for post traumatic injuries seen in other studies and males are more commonly affected than females15,16. A large number (80%) of our patients sustained their injuries in motor vehicle crashes, similar to findings by Chalya et al15 in Tanzania. Seventeen of the patients presented with non-unions, 10 of which were infected, representing 58.8%. Others have reported fewer cases of infected non-union in their series17. The high percentage of cases of infected non-union in this study was because the patients sustained open fractures, a risk factor for infected non-union.

The ASAMI criteria used for outcome measurement in this study revealed that most of the patients had good bony and functional outcomes. Other workers had reported higher values for good outcome but this report showed a learning curve1,14,18,19.

A sizeable number of patients (46.7%) in this study developed pin tract infection, higher than what some other workers had reported20,21. However, all the patients had Paley grades I and II infection which were successfully treated with antibiotics as recommended by other workers1,12. This study showed figures higher than findings by other workers because the patients were discharged rather early. Knee stiffness was observed in 20% of the patients following femoral lengthening procedures. This was observed early in the study and prompted us to perform the subsequent procedures with the knee flexed which reduced the number of patients with this complication. In addition to this, some of the patients who came late presented with knee stiffness being a complication of the treatment received prior to referral. Knee stiffness affected the ASAMI scores of these patients giving a relatively poor outcome.

The main limitations of our study were the relatively small number of patients and the limited period of follow-up of 2 years.

Conclusions

This study has shown that Ilizarov surgery is a good option for limb reconstruction especially in patients with limb length deformities and chronic osteomyelitis.

Fig. 4. Surgical Procedures.

Fig. 6. Failed implant with non-union and limb length discrepancy.

Fig. 7. Acute docking post implant removal and commencement of elongation.