Subaxial rotational vertebral artery syndrome: resection of the uncinate process and anterior fusion can be sufficient!: case report and review of the literature.

STUDY DESIGN: A case report on rotational vertebral artery syndrome (RVAS) and surgical treatment. OBJECTIVE: To illustrate a safe treatment option of RVAS with diminished risk of iatrogenic damage to the vertebral artery. SUMMARY OF BACKGROUND DATA: RVAS is an uncommon cause of symptomatic transient vertebrobasilar insufficiency induced by physiological head rotation with temporary significant external compression of the dominant subaxial vertebral artery. Previous reports state that the treatment of choice consists of decompression of the vessel with resection of the anterior rim of the transverse process and any fibrotic sheet or intertransverse muscle, if necessary, combined with an anterior cervical discectomy and fusion (ACDF) with uncus resection. METHODS: This is a case report on RVAS and its surgical treatment. The diagnosis of RVAS due to an osteophyte of the uncinate process at level C5/C6 was confirmed using computed tomographic angiography. We performed a classic ACDF using the contralateral approach with complete resection of the uncovertebral joint at the pathologic site. RESULTS: In our case, the symptoms of transient vertebrobasilar insufficiency induced by head rotation completely resolved postoperatively, and computed tomographic angiography images at 3 months postoperatively showed good bony ingrowth and restoration of vertebral artery patency during extreme rotation. CONCLUSIONS: Classic ACDF with complete resection of the uncovertebral joint is a safe treatment option for RVAS in the subaxial cervical spine. Fusion at the pathologic level will eliminate rotation and prevent further formation of osteophytes at the operated level. Unroofing of the vertebral artery seems not always necessary, diminishing the surgical risk.

The role of the deep medial collateral ligament in controlling rotational stability of the knee.

PURPOSE: The tibial insertion of the deep medial collateral ligament (dMCL) is frequently sacrificed when the proximal tibial cut is performed during total knee arthroplasty. The role of the dMCL in controlling the knee's rotational stability is still controversial. The aim of this study was to quantify the rotational laxity induced by an isolated lesion of the dMCL as it occurs during tibial preparation for knee arthroplasty. METHODS: An isolated resection of the deep MCL was performed in 10 fresh-frozen cadaver knees. Rotational laxity was measured during application of a standard 5.0 N.m rotational torque. Maximal tibial rotation was measured at different knee flexion angles using an image-guided navigation system (Medivision Surgetics system, Praxim, Grenoble, France) before and after dMCL resection. RESULTS: In all cases, internal and external tibial rotation increased after dMCL resection. Total rotational laxity increased significantly for all knee flexion angles, with an average difference of +7.8° (SD 5.7) with the knee in extension, +8.9° (SD 1.9) in 30° flexion, +7° (SD 2.9) in 60° flexion and +5.3° (SD 2.8) in 90° flexion. CONCLUSIONS: Sacrificing the tibial insertion of the deep MCL increases rotational laxity of the knee by 5°-9°, depending on the knee flexion angle. Based on our findings, new surgical techniques and implants that preserve the dMCL insertion such as tibial inlay components should be developed. Further clinical evaluations are necessary.

Internal fixation of an intertrochanteric femoral fracture after Birmingham hip resurfacing arthroplasty.

The Birmingham hip system is one of the most popular designs for hip resurfacing. Fractures associated with the Birmingham Hip Resurfacing (BHR) are mostly subcapital fractures. Other traumatic periprosthetic fractures are rarely reported. We report an intertrochanteric fracture which occurred after a Birmingham hip resurfacing. The fracture was treated with a reversed distal femoral locking plate, with a very satisfying clinical and radiological result.

The John Insall Award: Both morphotype and gender influence the shape of the knee in patients undergoing TKA.

UNLABELLED: There is an ongoing debate whether gender differences in the dimensions of the knee should influence the design of TKA components. We hypothesized that not only gender but also the patient's morphotype determined the shape of the distal femur and proximal tibia and that this factor should be taken into account when designing gender-specific TKA implants. We reviewed all 1000 European white patients undergoing TKA between April 2003 and June 2007 and stratified each into one of three groups based on their anatomic constitution: endomorph, ectomorph, or mesomorph. Of the 250 smallest knees, 98% were female, whereas 81% of the 250 largest knees were male. In the group with intermediate-sized knees, female knees were narrower than male knees. Patients with smaller knees (predominantly female) demonstrated large variability between narrow and wide mediolateral dimensions irrespective of gender. The same was true for larger knees (predominantly male). This variability within gender could partially be explained by morphotypic variation. Patients with short and wide morphotype (endomorph) had, irrespective of gender, wider knees, whereas patients with long and narrow morphotype (ectomorph) had narrower knees. The shape of the knee is therefore not only dependent on gender, but also on the morphotype of the patient. LEVEL OF EVIDENCE: Level I, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.