An 8-month old baby with failure to thrive, weighing just 5.3 kg was initially evaluated by Dr. Ann Agnes Mathew (Paediatric Neurologist, Rainbow Hospitals, Bangalore) for delayed developmental milestones. The baby had no head control and had weakness with diminished movements in the left hand and right leg. The initial step towards establishing a diagnosis, (as the causes of delayed milestones as well as weakness is varied) a preliminary MRI brain scan was undertaken which gave us an unexpected answer to the baby’s problems.
The MRI brain threw open a challenge to medical science!
The child had a rare anomaly with a malformed base of skull and a widened foramen magnum (the opening in the skull through which the spinal cord enters the brain). As a result, the skull settled down to sit on the second spinal bone (as opposed to the first spinal bone which is normally the resting place of the skull base). Apart from this, the skull had also slipped forwards over the neck bones (This is called Atlanto-axial dislocation, commonly known as AAD which is a fatal condition if left untreated). It was a miracle that the child had survived as long as it did, despite this deformity with such a severe compression to the brainstem – spinal cord junction, despite the lack of neck holding and muscular development. The only option for ensuring survival was a surgical remedy, which needed to address two issues. Firstly the severe spinal cord compression and secondly preventing further slippage.
This rare surgery was performed by Dr. Murali Mohan S & team at Sagar Hospitals, Bangalore. This child became the youngest child to have successfully undergone a corrective surgery for AAD across the globe. The first spinal bone had to be taken out from within the skull. With no space for instruments, the buried part of the bone had to be drilled out of the spinal cord. Once decompression was achieved, the next challenge was to fix the head in such a way that it wouldn’t slip over the neck bones again. As the bones were not fully developed and hence couldn’t accept even regular Paediatric size implants, the surgeon had to use innovative ideas to achieve stabilization. Titanium screws and plates were used to achieve this goal. Although this was a risky surgical affair, it was well accomplished by the team.
Dr. Gayathri, the Neuro Anaesthetist had several challenges to face as even tubing the child for anaesthesia had a high risk of death. Apart from this was the challenge of maintaining the vitals of the child for the 5-hour long duration of surgery, which was fraught with a high risk of threat to life. The child withstood the surgery well and was shifted to the ward the next day itself after surgery, to very relieved and happy parents. Their joy was enhanced by the fact that the child not only withstood such a complex surgery at such a tender age, but also that the baby came out victorious with improvement of movements in both the left hand and the right leg.
As a surgeon it takes immense courage to tackle unexpected surgical challenges that come in ones way. A standard teaching in medical science is that not all cases that we are going to treat are in our textbooks. One has to Weigh the risk of procedure, versus the natural risk of sure death in this situation if left untreated. It was a phenomenal challenge to tackle the situation, as surgery would be a major procedure requiring several hours. The first challenge was to determine wether the child had the potential to withstand a complex surgery and maintain vitals during this long duration, and Second, once the bone causing the pressure over the spinal cord is removed, how do we achieve stabilisation of the head and neck junction so that it does not slip again. This is simple in adults and older children as standard implants are available. At 8 months, with 5.3kg weight, the bones are too tender to accept standard implants.
Miraculously, the child not only withstood the procedure well, but also showed immediate improvement in limb movement and paresis to compound the joy of the parents.
This blog is about my personal experience and thoughts as a surgeon when we are faced with such challenges. It is easy not to take risks, and at the same time it is unwise to take risks!! Uncertain thoughts do crosses one’s mind, but by and large, the passion drives the proceedings. My take is very personal, if one’s thoughts are pure and the intentions are very clear, which is patient healing, calculated risks is a necessity in these situations. However, this approach can be adopted only after thorough learning and experience in the given surgical territory. Practice makes men( or women) perfect. it holds good here too. The more a surgeon operates, he learns the surgical anatomy better enough to deal with absolute challenges like these.
disclaimer: Photo’s shared with permission