Since it was first described by Hippocrates in 460–377 BC, limb amputation has been a common surgical procedure performed by orthopedic, general, vascular and trauma surgeons for therapeutic reasons to serve patient’s life. However, it is often associated with profound economic, social and psychological effects on patient and their family [1, 2]. As amputation indications and patterns vary between hospitals in a country and between countries, this study was undertaken to describe our experiences on major limb amputations in a larger tertiary care teaching hospital and compare the findings with similar studies conducted in other parts of the world with a view to highlighting the variations in the pattern and indications for amputations. This would enable meaningful preventive measures to be proffered.
The male preponderance among amputee in the present study agrees with the findings by other authors [6, 7, 16–18]. We could not find any reasons to explain for the male preponderance in this series.
The majority of our patients were in the 4th and 5th decades which is comparable with other studies [6, 10, 18, 19] but in contrast with another study in Ghana which reported high peak age incidence in the 7th decade [20]. Other studies reported even lower peak age incidence [3, 21].
This age differences can be explained by variation in the cause and patterns of amputation which tend to vary between hospitals in the country and between countries.
Complications of diabetic foot ulcers were the most common indication for major limb amputation in our study, followed by trauma and peripheral vascular diseases. Similar trend was also reported in other series [10, 20–23]. A similar pattern was also seen in the West where Pohjolainen & Alaranta [24] reported that 49% of amputations in Finland resulted from diabetic complication. These findings are not in agreement with other studies which reported trauma as the most common indication for major limb amputation [2, 6, 18, 25]. These differences in the pattern of indications reflect differences in incidences of different pathologies leading to limb amputation which tend to vary from one place to the other. The increased incidence of diabetic foot complications requiring lower limb amputation may reflect the level of effectiveness of the early detection of diabetes mellitus and the foot at risk, medical education, patient compliance and overall control of diabetes mellitus in this population. The risk of amputation in diabetic patients is increased up to 15 fold [26]. Factors contributing to this include sensory, motor neuropathy causing gait abnormality and deformity; autonomic neuropathy causing abnormal blood flow; macrovascular disease causing ischemia; poor glycaemic control causing increased risk of infection. Inadequate care of infection and ulceration is also a potentiating factor for limb amputation [10, 26].
In the present study, although trauma (commonly due to road traffic crashes) ranked second, it was found to be the most common indication for amputation in young adults in their productive and reproductive age group. Limb amputation in this group almost always result in a serious economic crisis for the family, especially that prosthesis are either unavailable or unavoidable [27, 28].
Studies have shown that approximately 80-90% of limb amputations in developed countries are performed as a result of vascular problems [13–15].
In our study, peripheral vascular diseases ranked third as indication for major limb amputation. This may be due to complications of diabetes mellitus. However, peripheral vascular disease (PVD) unrelated to diabetes mellitus was the most common cause of lower limb amputations in Kenya, contrary to the belief that PVD is only common in developed countries [22]. Further study is needed to explain such observation in our environment.
Postburn contractures commonly involving the upper limbs were the most common indications for amputation in children less than 10 years of age. This was followed by iatrogenic indications (prolonged use of tourniquet & complication of POP).and congenital limb deformity. Paudel et al.[2] in Nigeria reported post-burn contractures as the most common indication for amputation in children followed by congenital limb deformity and tumors. Increased incidence of post-burn contractures as indication for limb amputation reflects poor management of acute childhood burn injuries in these two populations.
In agreement with other studies [3, 6] most of our amputations were performed in the lower limbs and below knee amputation was the most common procedure performed. This finding confirms the earlier findings that lower extremities are injured more often than the upper extremities and diabetic gangrene is common on the lower extremities than elsewhere on the body [5, 29, 30]. However, other studies reported above knee amputation as the most common procedure performed than below knee amputation [3, 18, 31].
Late presentation with spreading gangrene or advanced diabetic foot gangrene or malignant lesions that have involved the underlying bones may force the surgeon to opt for a higher level of amputation [20, 27, 28].
The complication rate (33.3%) in our study is lower compared with that of Essoh et al.[6] in C↖Ðte d’Ivoire (39.0%). Surgical site infection was the most common complication in the present study and Staphylococcus aureus was the most common organism isolated. Similar microbiological trend was also reported by other authors [6, 18]. The overall surgical site infection rates in these studies reflect the severity of complications leading to amputation. Indeed, the majority of patients in these studies presented with spreading gangrene or diabetic septic foot.
The rate of re-amputation in our patients (9.9%) was found to be lower compared to that reported by Essoh et al. [6] in C↖te d’Ivoire (23%) but higher than that reported by Kidmas et al.[18] in Nigeria (7.4%). These differences in re-amputation rates may be explained as follows; firstly, late presentation with advanced disease increases the risk of revision amputation. Secondarily, the majority of amputations are performed by junior doctors with little experiences. Thirdly, high complication rates in our patients may also increase the risk of re-amputation. Fourthly, poor management of amputation stump is also a risk factor for re-amputation.
The mean duration of hospital stay in our study was 22.4 days, which is high than that reported in other studies [10, 32], but lower than that reported by other authors [6, 33, 34]. The length of hospital stay is an important measure of morbidity. Estimates of length of hospital stay are important for financial reasons, and accurate early estimates facilitate better financial planning by the payers. The duration of hospital stay has been identified as one of the main determinants of cost associated with amputation [35].
The mortality rate in the present study (16.7%) is comparable with that reported in other studies [6, 7, 18, 23], but significantly higher than that reported by Massod et al. [10] in Pakistan. The reasons for high mortality rate in our study are diabetic-related complications, wound sepsis and advanced malignancies with metastasis which were found to be common in our study.