Spinal health is an often overlooked by healthy patients. Until there is a problem, many people take their spine for granted. However, both disease and aging can lead to spinal deformations. While a deformed spine may not be straight, finding a solution involves much more than simply straightening the spine.

A sagittal imbalance is caused when the back loses its characteristic S-shape. This shape allows the human skeleton to resist the downward force of gravity. However, this S-shape can change due to bad posture, ill health or the inexorable march of time.

According to Professor Le Huec, chairman of the Bordeaux University Hospital Orthopaedic Department, the slopes and tilts of the back are based on a delicate equilibrium of different forces.

"Fish don't have lordosis. We see inappropriate kyphosis in humans causing imbalances in the forces involved in maintaining the erect position," he notes.

Each week, this French surgeon performs several operations with the goal of restoring the natural balance found in a patient's back. By forming a triangular part of a patient's spinal structure and adding screws and rods, he can restore the natural curvature of the spine. This technique, pioneered by Le Huec and others, has made great strides over the past decade.

One procedure, dubbed a Smith-Peterson Osteotomy (SPO), is only designed to change the posterior arch of a patient's vertebrae. However, this operation may involve the removal and resharing of a small part of a patient's vertebrae. In this technique, dubbed Pedicle Subtraction Osteotomy, a vertebra section is reshaped from rectangular to triangular.

"It is a long surgery, with an average loss of 1.5-2 litres of blood in the literature and potential complications has historically been very high, including infection, post-operative pain and muscle pain," Le Huec notes. "But 90% of patients say they are very happy because they lose their back pain and recover a normal life."

As patient populations age, the number of kyphotic patients increases. Almost all patients experience this type of degeneration after 60 years, according to Le Huec. However, anatomy is usually able to compensate for this change in four-fifths of patients.

Approximately 15 years ago, the French surgeon saw increasing numbers of patients with a flat back, the opposite condition. Oddly enough, this issue was due to a surgical procedure that had long been considered a success. During the 1980s, many physicians around the world pioneered new spinal surgery techniques. In particular, physicians learned treatment techniques for patients whose vertebrate had fused, hunching them forward.

As surgeons began using screw-based implants, bone fused much more easily in a desired position. However, physicians at the time did not respect a patient's natural spinal anatomy. In Le Huec's words, "In fact they were creating flat backs due to the position of the patient on the operating table. The majority of patients are in hypolordotic position on various frames during surgery."

Le Huec's latest contribution to the medical device arena is dubbed the ReDuX Plier. This device is designed for osteotomies in sagittal imbalanced patients. In particular, the device is indicated for patients suffering from pedicle subtraction osteotomy. Since current tools didn't work very well for patients suffering from these conditions, Le Huec worked with engineers to create a new instrument, giving patients greater control.

The ReDuX Plier is designed to connect directly to implants. The device helps protect the front of a patient's vertebrae from collapse in a unique way. By dissipating stress onto the bone screws by driving the kinematic of the closure (while a progressive correction is applied), the device allows for a highly-controlled procedure. The device was released on the market in June of this year.