Early Protected Weightbearing for Acute Ruptures of the Achilles Tendon: Do Commonly Used Orthoses Produce the Required Equinus?

Conservative “functional” management of acute Achilles tendon ruptures has become increasingly popular. Critical to this is the use of the walking orthosis, which positions the ankle in equinus to allow for early weightbearing. Our aim was to test whether 2 common orthoses achieved a satisfactory equinus position. A total of 11 sequentially treated Achilles tendon ruptures were assigned to either a fixed angle walking boot with wedges (FAWW) or an adjustable external equinus-corrected brace (EEB). The lateral radiographs of the cast immobilized tendons showed a mean tibiotalar angle (TTA) of 56° (range 54° to 57°) and a mean tibio-first metatarsal angle (1MTA) of 74° (range 62° to 85°). The FAWW resulted in a mean TTA of 28° (range 15° to 35°) and 1MTA of 37° (range 30° to 45°). The EEB resulted in a TTA of 48° (range 43° to 45°) and 1MTA of 54° (range 47° to 57°). Ankle equinus was significantly greater with the EEB than with the FAWW (p < .05) and similar to that with an equinus cast. The use of wedges produced an equinus appearance through the midfoot but not at the ankle. We express caution in the use of the FAWW because it is unlikely to achieve sufficient ankle equinus to shorten the Achilles tendon.     

Histological changes in the temporomandibular joint in rabbits depending on the extent of mandibular lengthening by osteodistraction

We studied the histological changes in the temporomandibular joint (TMJ) after unilateral mandibular distraction osteogenesis in rabbits. Eight rabbits were used, two of which served as controls and the other six had distraction of the left mandibular body after a latency period of 7 days at a rate of 0.5mm a day for a total of 2mm (n = 2), 3.5mm (n = 2), and 5mm (n = 2) of distraction. After a 14-day consolidation period, TMJs from both sides were harvested and prepared for histological examination under an optical microscope using haematoxylin and eosin stain. We found no degenerative or inflammatory changes in either TMJ in any of the groups. Endochondral ossification in the condyle was greater on the opposite side in the experimental group than in the condyles of the control group. Endochondral ossification was active in the 3.5-mm group.     

The relationship between distraction length and treatment indices during distraction osteogenesis

 To evaluate the indices used to compare the results of limb lengthening with distraction osteogenesis, we analyzed the relationship between the lengthening and external fixation period in a series of 28 patients (30 limbs). The average lengthening was 4.6  cm (range, 2.0–8.9). The average age at operation was 16.6 years (range, 4–47). Limbs treated included 15 femurs and 15 tibias of 19 male and 9 female patients. The external fixation period and the maturation period had a direct linear relationship with length gain. There was a negative hyperbolic relationship between the external fixation index, maturation index, and length gain. Segments that were lengthened 0–3.0  cm had a maturation index of 38.3 days/cm and external fixation index of 57.6 days/cm, both of which were significantly higher than for those lengthened more than 3.0  cm. When comparing the maturation and external fixation indices between different patients or studies, the length of the distraction must be taken into consideration. Received: June 14, 2001 / Accepted: January 7, 2002     

一次性根管治疗术分根术牙冠延长术桩核联冠联用于下颌第一磨牙残根残冠临床观察

目的观察下颌第一磨牙残根残冠经根管治疗、牙周手术及桩核联冠修复后的疗效。方法选68个下颌第一磨牙的残根残冠,贯序进行一次性根管治疗术、分根术、牙冠延长术及桩核联冠修复。结果随诊2年,2例失去联络,4例失败。成功率为93.94%。结论下颌第一磨牙残根残冠要尽量保留,进行上述贯序治疗,效果良好。     

Periprosthetic Femoral Fracture After a Well-Fixed Revision Total Knee Arthroplasty Treated With In Situ Effective Lengthening of Prosthesis

The increasing number of total knee arthroplasties implies a greater likelihood of periprosthetic fractures and need for successful treatment options. We report a case where in situ effective lengthening of the stem of a well-fixed indwelling prosthesis by a custom-made intramedullary nail with taper-lock coupling provided a successful alternative to the established internal fixation techniques involving prosthesis exchange. We believe that effective lengthening of indwelling prosthesis by a custom-made intramedullary nail is an effective option for treating periprosthetic femoral fractures in selected cases, where an attempt of removing well-fixed implant would result in unacceptable bone loss at the joint level.     

The feasibility of using an endoluminal device for intestinal lengthening

Purpose

Prior studies demonstrating the ability to lengthen intestinal segments with mechanical force required devices with extracorporeal components. The feasibility of using a completely implantable device for in vivo intestinal lengthening was evaluated in this study.

Methods

Biocompatible Nitinol springs capable of 5-fold expansions were compressed using absorbable sutures and were implanted into isolated segments of proximal jejunum in rats. Springs compressed with nonabsorbable sutures served as controls. The animals were observed with serial abdominal x-rays until the springs became fully expanded. Intestinal segments were then retrieved for histologic analysis. Two-tailed and paired Student's t tests were used for statistical analysis.

Results

Intestinal segments were successfully lengthened in the experimental group from 1.3 ± 0.3 cm to 4.4 ± 0.5 cm (P < .001). Maximum spring length was achieved on postoperative day 36 (range, 16-50 days). In the control group, there was also an increase in intestinal lengths, from 1.6 ± 0.04 cm to 2.9 ± 0.4 cm (P < .001) (Fig. 4). In percentages, a 250% increase in length was observed in the experimental group vs an 85% increase in the control group (P < .001). Microscopic evaluation of both control and experimental segments revealed gross preservation of intestinal architecture; however, muscular layer hypertrophy and villous atrophy were noted.

Conclusions

Continuous mechanical force with an implantable spring successfully lengthened isolated segments of small bowel in an animal model. Although similar results have been demonstrated using other devices, the current device is totally implantable and may be deployed endoscopically.