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Background Context: Cervical traction has a long history as a method of conservative treatment for cervical spine diseases. However, information on quantitative changes in the cervical neural foramen resulting from axial traction in vivo is lacking. Purpose: To quantitatively evaluate the changes in the neural foramen of the cervical spine during axial traction in vivo. Study Design: A prospective radiographic analysis of the cervical neural foramen of adult volunteers. Patient Sample: Fifteen healthy volunteers (10 men, 5 women) without any history of cervical spine disease. Outcome Measures: The changes in cervical cross-sectional foraminal areas and heights were measured. Methods: Cervical magnetic resonance (MR) images of the volunteers were taken at the neutral position and were reconstructed in the oblique plane perpendicular to the long axis of each neural foramen from the C2-3 to the C6-7 level. The changes in the neural foraminal dimensions at incremental axial traction forces (0, 5, 10, and 15 kg) were analyzed. Results: After each 5-kg incremental increase in traction weight, there was a significant (p value less than .05) increase in area and height of the intervertebral foramen compared with the position in which no weight was applied. There was an average increase of 5.81%, 16.56%, and 18.9% in the foraminal area and an average increase of 3.75%, 8.67%, and 10.43% in foraminal height compared with the position with no weight at traction of 5, 10, and 15 kg, respectively. There was no statistically significant difference for the increase in foraminal area and height from 10 to 15 kg of traction (p value greater than .05). Conclusions: There was a significant increase in intervertebral foraminal area and height after each 5-kg increment in traction weight compared with the position in which no weight was applied. From 10 to 15 kg of traction, there was no significant change in the foraminal area and height. [ABSTRACT FROM AUTHOR]

Background Context: The halo skeletal fixator provides the most rigid type of immobilization of all the orthoses that stabilize the cervical spine. Sometimes with older patients (>70 years old), the pin penetrates the cortical and cancellous bone of the skull and enters the intracranial space, which can result in serious complications such as brain injury, infection, hematoma, and loss of cerebrospinal fluid from the subarachnoid space. Currently, there is a lack of relevant literature that examines these concerns. Purpose: To evaluate the thickness of the outer table, diploe, and inner table at the anterolateral and posterolateral pin insertion areas of the skull in elderly cadavers by using computed tomography (CT) scans. In addition, insertion torques at the four standard pin insertion areas was determined by applying halo pins at incremental torque in an effort to suggest safe torque levels for the anterolateral and posterolateral pins. Study Design/setting: A human cadaveric anatomical and biomechanical study relating to thickness and insertion torques at standard pin areas in the elderly. Patient Sample: Twenty-one elderly cadaveric skull specimens. Outcome Measures: Thickness of cortices (tables) and diploe of skull and insertion torque at halo pin insertion areas. Methods: Aquarius Image software at the CT scanner's TeraRecon Aquarius Workstation was used to make the necessary skull thickness measurements at the pin insertion areas. Six, 8, 12, 18, and 36 inch lb of torque were used to determine penetration of the pins through the inner table at each of the four locations (two anterolateral and two posterolateral). Results: The mean anterolateral thickness was 7.36+/-1.57 mm. The average thickness of the outer table, diploe, and inner table were 2.24+/-0.44 mm, 1.52+/-0.41 mm, and 3.59+/-1.70 mm, respectively. The mean posterolateral thickness was 9.47+/-1.12 mm. The average thickness of the outer table, diploe, and inner table were 4.32+/-0.92 mm, 1.88+/-0.35 mm, and 3.27+/-1.21 mm, respectively. No pin penetration was seen at the traditional 8 inch lb of insertion torque in both the anterolateral and posterolateral pin insertion areas. Eighteen inch lb of torque resulted in penetration in 90.48% (19/21) and in 85.71% (18/21) of specimens in the left anterolateral and right anterolateral pin insertion areas, respectively. No penetration was seen even at 36 inch lb of torque in 80.95% (17/21) of the cadavers in both the left and right posterolateral pin insertion areas. Conclusions: The current study supported previous research that 8 inch lb of torque is safe for application of halo pins in the elderly. The posterolateral skull is thicker and stronger than the anterolateral skull. The safe maximum torque is 8 inch lb for anterolateral pin insertion area and 18 inch lb for the posterolateral pin insertion area. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Long-term results of patients treated with conventional laminoplasty have shown a significant number of patients complicated with kyphotic deformity. The authors hypothesize that by maintaining the spinous process–ligament–muscle complex (SPLMC) during laminoplasty, followed by postoperative muscle strengthening exercises, the formation of kyphosis can be decreased. Purpose: To evaluate the incidence of kyphosis in a select patient group undergoing laminoplasty with preservation of the SPLMC followed by neck strengthening exercises. Study design/setting: A midterm retrospective study of 30 patients following laminoplasty with preservation of the SPLMC. Patient sample: Thirty consecutive patients with cervical myelopathy attributable to multilevel cervical spinal stenosis underwent laminoplasty with preservation of the SPLMC from April 1998 to July 2002. Outcome measures: Preoperative and postoperative Japanese Orthopedic Association (JOA) scores, Guigui angles, and axial symptoms were measured. Methods: Thirty patients with multiple-level cervical myelopathy were studied. Fourteen had a normal lordotic curve, whereas 16 had a straight curve. All these patients underwent laminoplasty with preservation of the SPLMC. For the first 6 months, isometric neck muscle exercises were performed. After this time, the intensity of the exercises was gradually increased. Results: The average preoperative JOA score was 5.8±1.4. Mean JOA score at 3.8 years follow-up was 13.6±2.1. The recovery ratio was 69%. All 14 presurgical lordotic curves remained lordotic. Fourteen of the 16 straight spines improved to a lordotic configuration. Using the Guigui method, the preoperative lordotic angle was corrected by approximately 9 degrees (mean preoperative of 9.89±1.13 degrees, mean postoperative of 18.66±1.85 degrees), and the preoperative straight angle was corrected by approximately 15 degrees (mean preoperative of 0.91±2.14 degrees, mean postoperative of 15.88±1.71 degrees). Conclusions: Laminoplasty with preservation of the SPLMC followed by appropriate postoperative muscle exercises may be an encouraging way to maintain or restore the physiological curve and prevent kyphotic deformity at a medium term follow-up. [Copyright &y& Elsevier]

Abstract: A wideband (WB) aural acoustical test battery of middle-ear status, including acoustic-reflex thresholds (ARTs) and acoustic-transfer functions (ATFs, i.e., absorbance and admittance) was hypothesized to be more accurate than 1-kHz tympanometry in classifying ears that pass or refer on a newborn hearing screening (NHS) protocol based on otoacoustic emissions. Assessment of middle-ear status may improve NHS programs by identifying conductive dysfunction and cases in which auditory neuropathy exists. Ipsilateral ARTs were assessed with a stimulus including four broadband-noise or tonal activator pulses alternating with five clicks presented before, between and after the pulses. The reflex shift was defined as the difference between final and initial click responses. ARTs were measured using maximum likelihood both at low frequencies (0.8–2.8kHz) and high (2.8–8kHz). The median low-frequency ART was elevated by 24dB in NHS refers compared to passes. An optimal combination of ATF and ART tests performed better than either test alone in predicting NHS outcomes, and WB tests performed better than 1-kHz tympanometry. Medial olivocochlear efferent shifts in cochlear function may influence ARs, but their presence would also be consistent with normal conductive function. Baseline clinical and WB ARTs were also compared in ipsilateral and contralateral measurements in adults. [Copyright &y& Elsevier]