The Incidence of Depressed Skull Fractures Due to the Use of Pin-Type Head Frame Systems in the Adult Population: 10-year Experience of a Single Neurosurgical Center

OBJECTIVE

Pin-type head frame systems have become a worldwide standard procedure, but they can cause some complications on rare occasions. This study aimed to examine the incidence and associated risk factors of depressed skull fracture and related intracranial hematoma (DSFH) due to the use of head frames in our institute over the past 10 years.

METHODS

This study included 1749 patients who underwent neurosurgical surgeries using pin-type head frames, including the Mayfield (Integra NeuroSciences, Plainsboro, NJ) skull clamp (721 cases) and the Sugita (Mizuho Ikakogyo Co., Ltd., Tokyo, Japan) head frame (1028 cases). We retrospectively reviewed hospital records of our institute to identify cases of DSFH, and documented the type of head frame used, as well as patient characteristics.

RESULTS

The incidence of DSFH was 0.29% (5 of 1749 cases). All 5 cases had an associated epidural hematoma, with a single case having an additional dural laceration (without subdural damage). All perforation sites, located at the parietal bone near the pterion, occurred by the unilateral horizontal screw of the Sugita head frame. None of the patients experienced postoperative neurological decline.

CONCLUSIONS

Even in the adult population, the DSFH by the pin-type head frame can occur infrequently. Based on our results, we recommend that the following factors should be considered when the pin-type head frame is used for neurosurgical procedures: location of pin application, thickness and fragility of the skull, and adequate control of compressive forces exerted by the head frame.

Measurement of Cervical Sagittal Alignment Parameters on X-Ray Films of Adults without Severe Spinal Deformity Whose Shoulder Hides the Lower Cervical Column

OBJECTIVE

The Cobb angle between the lower endplate of C2 and C7 (C2L-C7L angle) is a traditional parameter used for the assessment of the cervical alignment. However, when the lower cervical column is masked by the shoulder, measurements are difficult. In the present study, we inspected 191 X-ray films, measured the Cobb angle between C2L and the endplates at the several levels of the lower cervical column, and assessed their usefulness of such measurements for the determination of cervical sagittal alignment.

METHODS

We obtained X-ray films on 191 patients ranging in age from 20 to 93 years. The Cobb angle between C2L and the C7 upper (C7U), the C6 lower (C6L), the C6 upper (C6U), and the C5 lower endplate (C5L) was measured and compared with the C2L-C7L angle.

RESULTS

C7L was identified in 116 of 191 patients (60.7%). Except for C2L-C7U angle (P = 0.55), the difference in the mean between C2L-C7L angle and the angle between C2L and the other endplates was statistically significant (P < 0.05). There was a very strong correlation between C2L-C7L angle and C2L-C7U angle (r = 0.99), C2L-C6L angle (r = 0.96), C2L-C6U angle (r = 0.94), and C2L-C5L angle (r = 0.86).

CONCLUSIONS

To measure the C2L-C7L angle on unclear X-ray films, C7U can be substituted for C7L. Our measurement data for the C6 and C5 endplates were statistically different; however, the correlation between the C2L-C7L angle and C2L-C6U angle, C2L-C6L angle or C2L-C5L angle was very strong. In patients with unclear lower vertebral bodies, cervical sagittal alignment can be predicted by using adjacent endplates.

Postoperative Changes in Metabolic Parameters of Patients with Surgically Controlled Acromegaly: Assessment of New Stringent Cure Criteria

The criteria for surgical cure of acromegaly have become more stringent during the past decades and a change from Cortina to new consensus criteria has recently been proposed. However, the superiority of the new consensus over Cortina criteria with respect to postoperative metabolic parameters remains to be ascertained. We retrospectively assessed metabolic parameters, the body habitus, and other health-related parameters of 48 patients with surgically controlled acromegaly who met the Cortina criteria [normalized insulin-like growth factor-1 (IGF-1) level and nadir growth hormone (GH) level <1.0 ng/ml during postoperative oral glucose tolerance test]. The 48 patients were divided into two groups. Group A (n = 33) met the new consensus criteria (normalized IGF-1 and nadir GH level <0.4 ng/ml). Group B (n = 15) met Cortina criteria, but their nadir GH ranged from 0.4 to 1.0 ng/ml. In both groups, the level of triglyceride and homeostasis model assessment-insulin resistance (HOMA-IR) was significantly decreased 1 year after the operation (P < 0.05). High-density lipoprotein cholesterol showed a significant increase only in group B (P = 0.02). However, the two groups did not differ with respect to the postoperative improvement rate of these parameters and the other health-related parameters including body mass index, blood pressure, anterior pituitary function, and self-estimated quality of life scale. In conclusion, our findings show that with respect to changes in metabolic parameters and the body habitus assessed 1 year after surgery, the stricter consensus criteria seemed not to be superior to Cortina criteria.