A recent article emphasizes the need to focus on breathing care prior to and after scoliosis surgery. In the article, 10 patients with CMD undergoing scoliosis surgery are taught simple breathing exercises prior to surgery using an inspiratory muscle trainer (IMT) with an increase in breathing capacity, measured by % FVC (forced vital capacity). This article describes the approach this particular orthopedic group in Japan uses when planning scoliosis surgery in patients with multiple types of CMD (3 patients with Fukuyama CMD, 3 patients with UCMD and 4 patients with merosin negative CMD). The mean age of surgery was 13 years. All 10 patients described had abnormal % FVC prior to surgery and all were nonambulatory (non-walkers). All patients were trained with inspiratory muscle training using an IMT device (Threshold IMT, Philips Respironics, Murrysville, PA) and used the device both 6 weeks prior to and after surgery. After using the device, all patients had an increase in % FVC prior to surgery.
A discussion of the particular surgical approach highlights pedicle-screw-alone fixation and fusion to L5 is safe and effective in CMD patients with scoliosis of <95% and pelvic obliquity of < 20%. Scoliosis curves were flexible (75% correction) on side-bending films preoperatively. Patients are undergoing long-term follow up to track pelvic obliquity and longterm success of this approach.
Anesthesia used rapid onset medications, propofol and remifentanil, tracked with a bispectral index monitor intra-operatively, allowing for rapid emergence, recovery from anesthesia and early extubation in the operating room. Mean total blood loss was 1590ml, highlighting the potential for blood loss during surgery which may be due to fibrosis of paraspinous muscles and the need to discuss the option of banking blood prior to surgery per family consent. Paralytic ileus (slowing down of the intestines) occurred in 2 patients postoperatively, was cited as the main complication and cleared within 48 hours.
Up to 6 weeks postoperatively, the mean % FVC remained stable or increased slightly. However, after 6 weeks, the % FVC decreased continuously through last follow up (mean follow up 3 years and 5 months).
The authors believe that an % FVC < 30% does not predict pulmonary complications post-operatively. 5/10 patients in this series had a pre-operative % FVC<30%. Inspiratory muscle training, rapid emergence anesthetics, a multi-disciplinary approach and the exclusion of any patients with heart problems or patients who are ventilator dependent may have contributed to the absence of pulmonary post-operative complications seen in this study.
Takaso M, Nakazawa T, Imura T, Okada T, Ueno M, Saito W, Takahashi K, Yamazaki M, and Ohtori S. Surgical Correction of Spinal Deformity in Patients with Congenital Muscular Dystrophy. J Orthop Sci 2010;15:493-501.