Gennis Elisabeth, Koenig Scott, Rodericks Deirdre, Otlans Peters, Tornetta Paul
Boston Medical Center, Boston, MA, USA
ProHEALTH Care Associates, Lake Success, NY, USA.
Foot Ankle Int. 2015 Oct;36(10):1202-8. doi: 10.1177/1071100715588186. Epub 2015 Jun 3.
A prior study demonstrated statistical widening of the syndesmosis within weeks of elective screw removal. However, no information is available as to the radiographic outcomes of screw retention. The aim of this study was to evaluate radiographic syndesmotic widening and talar shift over time in patients treated with syndesmotic screws and to compare screw removal with retention along with other potential risk factors that may have led to tibia-fibula diastasis after weightbearing.
One hundred sixty-six skeletally mature patients with ankle fractures and concomitant syndesmotic injuries were treated with syndesmotic reduction and screw fixation. The syndesmosis was evaluated intraoperatively either by a stress test or direct visualization. If the syndesmosis was incompetent, it was reduced and stabilized with syndesmotic screws to maintain reduction. Anteroposterior, mortise, and lateral radiographs at presentation, postoperatively, and at follow-up after weightbearing were evaluated. We measured the medial clear space (MCS), tibia-fibula overlap (OL), and tibia-fibula clear space (CS). Screws that were retained were graded as loose/broken or intact.
The fibula shifted an insignificant amount on postoperative mortise radiographs after elective syndesmotic screw removal at 3 months or more after initial fixation, indicated by a slightly greater CS and lower OL. The MCS did not change from preoperative to postoperative screw removal. There was no change in the radiographic markers from the postoperative to final follow-up images in those whose screws became loose or broken. Likewise, there was no radiographic difference if screws remained intact versus those that were loose or broken.
In contradistinction to prior work, we found that only very mild widening (0.5 mm) of the tibia-fibula space occurred after weightbearing following syndesmotic fixation. The removal of syndesmotic screws at 3 months resulted in a slightly lower OL (<1 mm) and greater CS (0.5 mm) on mortise radiographs than screw retention even if the retained screws loosened or broke. This was not associated with any talar subluxation, and these differences were not statistically significant. The mortise remained intact whether the syndesmotic screws were removed, were loosened or broken, or remained solid.
Level IV, retrospective case series.
先前的一项研究表明，在择期取出螺钉后的数周内，下胫腓联合出现统计学上的增宽。然而，关于螺钉保留的影像学结果尚无相关信息。本研究的目的是评估下胫腓联合螺钉固定患者下胫腓联合的影像学增宽及距骨移位随时间的变化情况，并比较取出螺钉与保留螺钉的情况以及其他可能导致负重后胫腓骨分离的潜在危险因素。
166例骨骼成熟的踝关节骨折合并下胫腓联合损伤患者接受了下胫腓联合复位及螺钉固定治疗。术中通过应力试验或直接观察评估下胫腓联合情况。如果下胫腓联合不稳定，则进行复位并用下胫腓联合螺钉固定以维持复位。对就诊时、术后及负重后随访时的前后位、斜位和侧位X线片进行评估。我们测量了内侧间隙（MCS）、胫腓骨重叠（OL）和胫腓骨间隙（CS）。保留的螺钉分为松动/断裂或完整。
在初次固定3个月或更长时间后择期取出下胫腓联合螺钉后，术后斜位X线片上腓骨移位不明显，表现为CS略增大和OL略降低。从术前到取出螺钉后，MCS没有变化。螺钉松动或断裂的患者，从术后影像到最终随访影像，影像学指标没有变化。同样，螺钉完整与松动或断裂的患者在影像学上没有差异。
与先前的研究不同，我们发现下胫腓联合固定后负重时，胫腓骨间隙仅出现非常轻微的增宽（0.5mm）。即使保留的螺钉松动或断裂，3个月时取出下胫腓联合螺钉在斜位X线片上的OL略低于（<1mm）保留螺钉，CS略大于（0.5mm）保留螺钉。这与距骨半脱位无关，且这些差异无统计学意义。无论下胫腓联合螺钉是取出、松动或断裂还是保持稳固，斜位均保持完整。
IV级，回顾性病例系列。
