Long-Term Follow-Up Comparative Study of Hydroxyapatite and Autologous Cranioplasties: Complications, Cosmetic Results, Osseointegration.

OBJECTIVE: A three-dimensional reconstruction technique using the CustomBone (CB) prosthesis allows custom-made cranioplasty (CP) possessing osseointegration properties owing to its porous hydroxyapatite (HA) composition. This reconstruction technique has replaced less expensive techniques such as subcutaneously preserved autologous bone (SP). Our primary objective was to evaluate complications between CB and SP CP techniques. A secondary objective was to assess cosmetic results and osseointegration of CPs. METHODS: This single-center study comprised patients undergoing delayed CB or SP CP after craniectomy between 2007 and 2014. A prospective interview was conducted to collect all data, including 2-year follow-up clinical and radiologic data. Cosmetic results were assessed by a qualitative score, and osseointegration was assessed by measuring relative fusion at the CP margins. RESULTS: Of 100 patients undergoing CB or SP CP between 2007 and 2014, 92 (CB, n = 44; SP, n = 48) participated in the prospective interview. No significant difference in complication rates was observed between the 2 groups. The main complication specific to the CB group was fracture of the prosthesis observed in 20.8% patients. A higher rate of good cosmetic results was observed in the CB group (92.5% vs. 74.3%, P = 0.031). In the CB group, 51% of patients demonstrated no signs of bone fusion of the CP. CONCLUSIONS: Although the CB prosthesis is associated with cosmetic advantages, the porous hydroxyapatite composition makes it fragile in the short-term and long-term, and effective osseointegration remains uncertain.

A good preoperative response to transcutaneous electrical nerve stimulation predicts a better therapeutic effect of implanted occipital nerve stimulation in pharmacologically intractable headaches.

Occipital nerve stimulation (ONS) is a surgical approach to treat patients with medically intractable chronic headache disorders. However, no preoperative test has been yet validated to allow candidates to be selected for implantation. In this study, the analgesic efficacy of transcutaneous electrical nerve stimulation (TENS) was tested for 1 to 3 months in 41 patients with pharmacologically intractable headache disorders of various origins, using a new technique of electrode placement over the occipital nerve. ONS electrodes were subsequently implanted in 33 patients (occipital neuralgia [n=15], cervicogenic headache [n=7], cluster headache [n=6], chronic migraine [n=5]) who had responded at least moderately to TENS. Assessment was performed up to five years after implantation (three years on average), based on the mean and maximum daily pain intensity scored on a 0-10 visual analogue scale and the number of headache days per month. Both TENS and chronic ONS therapy were found to be efficacious (57-76% improvement compared to baseline on the various clinical variables). The efficacy of ONS was better in cases of good or very good preoperative response to TENS than in cases of moderate response to TENS. Implanted ONS may be a valuable therapeutic option in the long term for patients with pharmacologically intractable chronic headache. Although we cannot conclude in patients with poor or no response to TENS, a good or very good response to TENS can support the indication of ONS therapy. This preoperative test could particularly be useful in patients with chronic migraine, in whom it may be difficult to indicate an invasive technique of cranial neurostimulation.

Odontoid balloon kyphoplasty associated with screw fixation for Type II fracture in 2 elderly patients.

Anterior screw fixation is a well-recognized technique that is used to stabilize Type IIB fractures of the odontoid process in the elderly. However, advanced age and osteoporosis are 2 risk factors for pseudarthrosis. Kyphoplasty has been described in the treatment of lytic lesions in C-2. The authors decided to combine these 2 techniques in the treatment of unstable fractures of the odontoid. Two approximately 90-year-old patients were treated for this type of fracture. Instability was demonstrated on dynamic radiography in one patient, and the fracture was seen on static radiography in the other. Clinical parameters, pain, range of motion, 36-Item Short Form Health Survey (SF-36) score (for the first patient), and radiological examinations (CT scans and dynamic radiographs) were studied both before and after surgery. After inflating the balloon both above and below the fracture line, the authors applied a high-viscosity polymethylmethacrylate cement. Some minor leakage of cement was noted in both cases but proved to be harmless. The screws were correctly positioned. The clinical result was excellent, both in terms of pain relief and in the fact that there was no reduction in the SF-36 score. The range of motion remained the same. A follow-up CT scan obtained 1 year later in one of the patients showed no evidence of change in the materials used, and the dynamic radiographs showed no instability. This combination of kyphoplasty and anterior screw fixation of the odontoid seems to be an interesting technique in osteoporotic Type IIB fractures of the odontoid process in the elderly, with good results both clinically and radiologically.

Benefits of repetitive transcranial magnetic stimulation (rTMS) for spastic subjects: clinical, functional, and biomechanical parameters for lower limb and walking in five hemiparetic patients.

Introduction. Spasticity is a disabling symptom resulting from reorganization of spinal reflexes no longer inhibited by supraspinal control. Several studies have demonstrated interest in repetitive transcranial magnetic stimulation in spastic patients. We conducted a prospective, randomized, double-blind crossover study on five spastic hemiparetic patients to determine whether this type of stimulation of the premotor cortex can provide a clinical benefit. Material and Methods. Two stimulation frequencies (1 Hz and 10 Hz) were tested versus placebo. Patients were assessed clinically, by quantitative analysis of walking and measurement of neuromechanical parameters (H and T reflexes, musculoarticular stiffness of the ankle). Results. No change was observed after placebo and 10 Hz protocols. Clinical parameters were not significantly modified after 1 Hz stimulation, apart from a tendency towards improved recruitment of antagonist muscles on the Fügl-Meyer scale. Only cadence and recurvatum were significantly modified on quantitative analysis of walking. Neuromechanical parameters were modified with significant decreases in H max⁡ /M max⁡ and T/M max⁡ ratios and stiffness indices 9 days or 31 days after initiation of TMS. Conclusion. This preliminary study supports the efficacy of low-frequency TMS to reduce reflex excitability and stiffness of ankle plantar flexors, while clinical signs of spasticity were not significantly modified.