Scoliosis: Correcting the curve

Posted on 31 October 2019

The spine is such an incredible design. From birth, it progressively changes shape from the C-form seen in a foetus to the S-shape observed in adulthood. This change occurs under stress from gravity and anti-gravity muscle development, with progression from lying position in a baby, to seated position, then starting to crawl, and eventually stand and walk. Various organs and systems play a role, including central and peripheral nervous system, muscles and skeleton.

For Dr Johan Davis, an orthopaedic surgeon based at Mediclinic Winelands Orthopaedic Hospital, spinal pathology and deformity is his passion. Correcting spinal abnormalities and performing deformity correction or reconstructive back surgery, is something he specialises in.  His journey started with an AO Spine Fellowship under guidance of Dr Robert Dunn at Groote Schuur Hospital. Subsequently Dr Davis occupied the position as head of Orthopaedic Spinal services at Tygerberg Academic Hospital, a role that he has recently passed on to one of his own Trainees and he now also plies his trade within the Institute of Orthopaedics and Rheumatology (IOR) in Stellenbosch, that partners with Mediclinic Winelands Orthopaedic Hospital. Dr Davis is a member of the academic board for IGASS (International Group for Advancement in Spinal Science), and has hosted an IGASS-backed internationally recognised fellowship programme for a number of years now.

As with anything else in nature, the growth and development of the spine may not always go according to plan. Early onset scoliosis is sometimes caused by congenital anomalies, syndromic etiologies or neuro-muscular causes, such as cerebral palsy or muscular dystrophy, and results in young children seeing the side-to-side deformity of the spine developing before the age of 10.

If left unchecked this potentially devastating condition results in severe spine and chest wall deformity through growth. This in turn may result in lungs that are underdeveloped in terms of functionality. In the long term, thoracic insufficiency syndrome may occur – a condition with cardiorespiratory compromise and a diminished life expectancy.

According to Dr Davis, there are a number of surgical options to consider if conservative modalities fail, or are not deemed appropriate. Each of these carry their own difficulties and potential problems. “The universal theme is one of guided or controlled growth, where we allow the spinal column to lengthen through normal growth. The curvature of the spine is controlled, limiting the progression in deformity until we have seen adequate growth to allow near normal (functional) respiratory capacity. At this point a definitive fusion procedure can be done, allowing for a final and permanent solution.” To facilitate this controlled growth for young patients, innovative solutions are required.”

Magnetic growing rods are part of this group of innovative solutions. “While they are relatively well established internationally now, I was the first to use magnetic growing rods in South Africa (June 2017) in Stellenbosch, and currently have a number of the children with early onset scoliosis being treated, both in my practice and at Tygerberg Academic Hospital with this modality,” explains Dr Davis.

A magnetic growing rod consists of single or dual titanium spinal rods that contain a magnetically drivable lengthening mechanism. The outcomes of these growing rods are favourable in certain aspects compared to the traditional growing rod technique, where open surgical lengthening had to be performed every six months. Implant associated complication (breakage) rates are similar: however infection risk and number of surgical interventions and anaesthesia events are significantly less. This helps with the treatment of a specific patient group with a condition that is very difficult to treat, often with high complication rates, irrespective of the technique used to treat them.

According to Dr Davis, “While the long term prognosis of this kind of surgery relies heavily on the underlying pathology, if surgical management and guided growth are successful, the long term prognosis is favourable for these patients.”

Adolescent idiopathic scoliosis is the most commonly found type of scoliosis in children. As the name implies, this is usually identified with the advent of the teenage growth spurt. The risk in these cases, beyond the general quality of life, is excessive deformity, resulting in effort intollerance, again through chest wall deformity.  Unacceptable cosmesis can also cause severe emotional distress in the teenage patient.  As this usually presents during adolescence, the spine can be considered to have grown enough to be considered as “grown”. As there is no further growing required, a definitive fusion procedure can be performed when indicated, fixating the spine in a more favourable position, a permanent solution. “I can attest to the dramatic personality transformation and change in confidence, in teenagers having to deal with a perceived malformed body, turning into confident and happy young people, through an appropriate intervention at the right time. A real metamorphosis with transformation into a butterfly,” says Dr Davis.

In adult patients, scoliosis is encountered for various reasons, sometimes through degeneration, or progression of a mild adolescent idiopathic scoliosis curve through degenerative “age-related” changes in the spine. Unfortunately, in some cases, adult spinal deformity is brought on by failed previous spinal procedures resulting in loss of hollow-curve of the lower back. Once the tall spinal column is pushed out af acceptable alignment one has to utilise compensatory trunk- and lower limb muscles and methods to allow erect stance. For patients, this in turn causes rapid fatigue due to inefficient energy consumption, a diminished walking distance and pain, often with severe debility.

These are potentially very difficult patients to deal with due to other existing co-morbidities such as osteoporosis, diabetes, heart conditions or other illness often part and parcel to patients in this age group.

The surgery requires break-down of prevoius fusions done in a poor position, and in severe cases, bony wedges can be cut out of the spinal column to re-attach and fix the spine in a more appropriate and well aligned position, to establish a normal stance and walking abilities.

This type of re-constructive surgery is difficult and only suited to a select group of patients that can safely endure such an extreme intervention.

When speaking to Dr Davis around corrective surgery for scoliosis, his passion becomes very clear.

He concludes, “This surgery is having a significant effect on the quality of life for my patients and is a key motivator to take on some of the more challenging cases.”

“I believe that the teaching and training provided through fellowship programmes are paramount to teaching the more challenging nuances of spinal surgery. I am proud of the excellent surgeons who have come through our IGASS fellowship programme, a number of whom have sought further employment at large referral centers and academic hospitals in the public sector in South Africa. This exponential growth in expertise and abilities in the public and private sector touches many lives and I am happy to be part of it in some way”.