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Cervical pedicle screws have been reported to be biomechanically superior to lateral mass screws. However, placement of these implants is a technical challenge. The purpose of this investigation was to use an anatomic and a clinical study to evaluate a technique for placement of the pedicle screws in the C7 vertebra using fluoroscopic imaging in only the anteroposterior (A/P) plane. Ten adult cadaver C7 vertebrae were used to record the pedicle width, inclination and a suitable entry point for placement of pedicle screws. A prospective study of 28 patients undergoing posterior instrumentation of the cervical spine with C7 pedicle screw placement was also performed. A total of 55 C7 pedicle screws were placed using imaging only in the A/P plane with screw trajectory values obtained by the anatomic study. Radiographs and CT scans were performed post-operatively. The average posterior pedicle diameter of C7 vertebra was 9.5 ± 1.2 mm in this study. The average middle pedicle diameter was 7.1 mm and the average anterior pedicle diameter was 9.2 mm. The average transverse pedicle angle was 26.8 on the right and 27.3 on the left. CT scans were obtained on 20 of 28 patients which showed two asymptomatic cortical wall perforations. One screw penetrated the lateral wall of the pedicle and another displayed an anterior vertebral penetration. There were no medial wall perforations. The preliminary results suggest that this technique is safe and suitable for pedicle screw placement in the C7 vertebra.

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Methods: A retrospective review of 117 consecutive 'all inside' arthroscopic meniscal repairs using a single suture technique from 1993 to 2006 by a single surgeon identified 53 isolated repairs and 64 in combination with ACL reconstruction. All tears were 2 cm or greater. Age averaged 30 years (range: 13-65). Outcomes of age, gender, and medial vs. lateral sidedness were also studied. Meniscal repair failure was defined as recurrence of pain at the repair site.Results: At an average follow-up of 38 months, there were 9 failures (7.7%). The average time to failure was 24 months (range: 3-108), with 6 requiring surgical intervention. Three failed in the ACL group (4.6%) and 6 in the non ACL group (12.9%), with no statistical difference between the two groups (pϭ0.12). Medial tears were more prevalent than lateral tears, 74% versus 26%. All repair failures were medial. Age greater than 40 was not significant for failure (pϭ0.26). Side and gender were also not statistically significant (pϭ0. 22 and pϭ0.23, respectively).Conclusions: In this study, age, gender, 'sidedness', were not significant factors for meniscal repair failure. The overall rate of successful healing of meniscal repairs was 92%. Lateral meniscal repairs fared better than medial meniscal repairs. Age and concomitant anterior cruciate ligament reconstruction had no impact on outcome.