Spinous process morphology: the effect of ageing through adulthood on spinous process size and relationship to sagittal alignment.

STUDY DESIGN: Blinded radiographic analysis of CT scans reformatted for precise lumbar spinous process (LSP) measurement. OBJECTIVE: To investigate the effect of ageing on LSP morphology and influence of LSP morphology on lumbar spine sagittal alignment. SUMMARY OF BACKGROUND DATA: There is little data reporting the influence of ageing on spinous process size. There is data describing the increase in size of other body parts with age, such as the femur, ears, vertebral body, and nose. Several old cadaveric and radiographic studies have reported the formation of osseous spurs within the supraspinous and interspinous ligaments. METHOD: 200 abdominal CT scans taken for trauma and vascular investigation were reformatted to allow precise bony measurement of the lumbar spine. Two observers were blinded from the age and demographics of the patients. Sagittal and coronal plane projections were used to measure the height and width of the spinous processes (L1-L5), respectively. The relationship between spinous process size, age, and supine lordosis was investigated. RESULTS: LSP height increases by 0.03-0.07 mm/year (p < 10(-3) to 10(-8)) and width by 0.05-0.06 mm/year (p < 10(-11) to 10(-15)). Lumbar lordosis decreases with increasing LSP height (p < 0.0004) but is not related to increasing LSP width (p = 0.195). Supine lordosis increases by 0.1°/year (p = 0.004). CONCLUSIONS: This study demonstrates that the dimensions of the LSP change with age. Increases in LSP height and even more impressive increases in LSP width occur with advancing age. There is an inverse relationship between lumbar lordosis and LSP height.

Posttraumatic proximal tibial growth arrest: a rare injury managed successfully with ring fixators.

A ring fixator was used in the treatment of five patients (ages 11 to 16 years) with proximal tibial growth arrest after trauma. The mean corrections were 14.2 degrees (maximum 28 degrees , minimum 0 degrees ) in the saggital plane and 14 degrees (maximum 38 degrees , minimum 2 degrees ) in the coronal plane. Leg length discrepancy was also corrected (max 1 cm). The average time in frame was 17.8 weeks, with an average correction time of 29.8 days. Knee Society Clinical Rating System scores post operatively ranged from 95-100. All patients returned to full activity, and would accept the same treatment if offered again. The circular fixator is an effective, minimally invasive method for treating the complex deformities arising from this rare injury. Patients remain active during treatment, encouraging a rapid return to school/work activities.

Cauda equina syndrome: factors affecting long-term functional and sphincteric outcome.

STUDY DESIGN: Retrospective cohort study with prospective clinical follow-up. OBJECTIVE: To determine the factors that influence outcome after surgery for cauda equina syndrome (CES). SUMMARY OF BACKGROUND DATA: CES is a rare but serious consequence of lumbar disc prolapse and can have devastating long-lasting neurologic consequences. The timing of surgical decompression remains controversial. METHODS: Fifty-six patients with evidence of a sphincteric disturbance who underwent urgent surgery were identified and invited to follow-up. The outcome measures comprised history and examination and several validated self-assessment questionnaires. RESULTS: Forty-two patients (78%) attended with a mean follow-up of 60 months (range, 25-114 months). Mean age at onset was 41 years (range, 24-67 years) with 23 males and 19 females. Twenty-six patients were operated on within 48 hours of onset of sphincteric symptoms; 5 of these were within 24 hours. Acute onset of sphincteric symptoms and the time to operation did not influence the outcomes. Leg weakness at onset persisted in a significant number of patients at follow-up (P < 0.005). Urinary disturbance at presentation did not affect the outcomes. At follow-up, significantly more females had urinary incontinence (P < 0.005). Bowel dysfunction at presentation was associated with sexual problems at follow-up (P < 0.005). The 13 patients who failed their post operative trial without catheter had worse outcomes. The SF-36 scores at follow-up were reduced compared with age-matched controls in the population. The mean ODI was 29, Low Back Outcome Score 42, and VAS 4.5. The time elapsed from operation to follow-up was not found to influence the outcomes. CONCLUSIONS: In our series, the symptom duration before operation and the speed of onset do not affect the outcome more than 2 years after surgery. Based on the SF-36, ODI, and Low Back Outcome Scores, patients who have had CES do not return to a normal status.

Intraoperative pulmonary embolism of Harrington rod during spinal surgery: the potential dangers of rod cutting.

This is a case report and laboratory-based biomechanics study. The objective is to report the first case of Titanium rod embolisation during scoliosis surgery into the Pulmonary artery. To investigate the potential of an unconstrained cut Titanium rod fragment to cause wounding with reference to recognised weapons. Embolisation of a foreign body to the heart is rare. Bullet embolisation to the heart and lungs is infrequently reported in the last 80 years. Iatrogenic cases of foreign body embolisation are very rare. Fifty 1-2 cm segments of Titanium rod were cut in an unconstrained manner and a novel method was used to calculate velocity. A high-speed camera (6,000 frames/s) was used to further measure velocity and study projectile motion. The wounding potential was investigated using lambs liver, high-speed photography and local dissection. Rod velocities were measured in excess of 23 m s(-1). Rods were seen to tumble end-over-end with a maximum speed of 560 revolutions/s. The maximum kinetic energy was 0.61 J which is approximately 2% that of a crossbow. This is sufficient to cause significant liver damage. The degree of surface damage and internal disruption was influenced by the orientation of the rod fragment at impact. An unconstrained cut segment of a Titanium rod has a significant potential to wound. Precautions should be taken to avoid this potentially disastrous but preventable complication.