Total ankle replacement (TAR) success has improved since first-generation implants, but patient satisfaction continues to be less than knee and hip replacements. Little is known about variations in distal tibia anatomy between genders and across ethnicities; therefore it is unclear the extent to which current TAR prostheses accommodate variability in patient size and shape. This study quantified distal tibia morphometrics relevant to TAR design, and assessed differences between ethnicities and genders. The hypotheses were: (1) The anterior-posterior (AP) location of the dwell point of the tibia is centralized; (2) The sagittal radius of curvature of the tibial articulation increases with bone size; (3) Differences in dwell point location or sagittal radii between genders and ethnicities can be attributed to size differences between those populations. Tibial CT scans were obtained from cadavers or individuals of various ethnicities (Table 1). Landmarks were defined on digital models created from the scans, including medial and lateral edges of the distal tibial articulation (Figure 1a), and sagittal contours of the articulation (Figure 1b). The articulation center was defined as the average center point of all contours (Figure 1c). The AP center and AP length at the level of a distal tibial resection for TAR were determined, and the AP offset of the articulation center was calculated (Figure 1c). Differences in metrics for each ethnic and gender group were determined using a one-way Anova (P<.05) with Tukey's method for differentiating groups. Regression fits of AP offset, average medial radius, and average lateral radius were determined. Utilizing AP length as a covariate, ANCOVA was utilized to assess differences in AP offset and sagittal radii between gender and ethnic groups (P<.05).Introduction/Purpose
Methods
Management of massive, degenerative, and irreparable rotator cuff tears is challenging. Excessive re-tear rates and poor clinical outcome after standard repair have led to alternative methods of treatment. Tendon transfers and shoulder arthroplasty have had mixed results; both are invasive procedures with high potential morbidity. We began performing rotator cuff augmentation and replacement using GraftJacket allograft acellular human dermal matrix as a biologic minimally invasive alternative in this difficult population almost 6 years ago. This article highlights our preferred arthroscopic technique and early results. From January 2004 to June 2007, 45 patients (36 men, 9 women) with massive rotator cuff tears were treated arthroscopically with the GraftJacket allograft. All patients completed a preoperative University of California, Los Angeles (UCLA) score. Follow-up was a minimum of 2 years (range, 24–68 months) and patients completed UCLA, Western Ontario Rotator Cuff (WORC), and American Shoulder and Elbow Surgeons (ASES) scores.Purpose
Method
