背景和目的：雖然骨髓腔擴鑽用於互鎖式髓內釘治療，在臨床上已被報導有良好之成效，然而互鎖式髓內釘治療是否必須使用骨髓腔擴鑽仍是個疑問。本研究目的是探討骨髓腔擴鑽與否在使用互鎖式髓內釘治療閉鎖性不穩定脛骨幹骨折時，其結果是否有所差異。方法：以前瞻性、隨機性、比較性方法進行，研究對象為53 位在2002年7 月1 日至2004 年12 月31 日有閉鎖性不穩定脛骨幹骨折並接受髓內釘治療之病患，以癒合時間、型態、併發症及二次手術治療為主要之測量結果。結果：全體病患之平均骨折癒合時間為21 週(11~50 週)，在擴鑽組平均癒合時間為19 週，而沒有擴鑽之平均癒合時間則為23 週；手術時間、術間失血量、術後併發率、二次手術、植入失敗結果在擴鑽與否兩組皆無統計上顯著差異。併發症在近側與末端骨折發生較頻繁(p =0.003)；粉碎性骨折為影響癒合時間之重要因素(p = 0.037)，而嵌入釘較大則會因增加骨與植入表面之接觸而穩定性較高使骨頭更為強化(s = -2.48, p < 0.001)。結論：對於單一或者嵌入的中間三節脛骨幹骨折，骨髓腔擴鑽在擴鑽與否兩組都有令人滿意的結果，但是在治療近側與末端之高度粉碎性脛骨幹骨折，擴鑽道越大容納直徑較長之嵌入釘可使骨折癒合較容易。

Although reamed interlocking nailing has been reported to showgood clinical results, the introduction of stronger interlocking nails that can be inserted withoutreaming has raised questions as to whether intramedullary reaming is necessary. The objectives of thisstudy were to determine if any differences in outcomes exist between reamed and unreamed closedinterlocking nailing in patients with unstable closed tibial shaft fractures.The study wasconducted in a prospective, randomized, and comparative manner. Between July 1, 2002, andDecember 31, 2004, fifty-three consecutive patients with unstable closed tibial shaft fractures treatedwith intramedullary nail insertion with or without medullary canal reaming were included in thestudy. Time to fracture healing, the type and incidence of complications, and the number of secondaryprocedures performed to obtain union were the main outcome measurements.The overallaverage fracture healing time was 21 (range, 11~50)weeks. In the reamed group, the fractures healed inan average of 19 weeks, while in the unreamed group, it took an average of 23 weeks. Differences inoperative time, perioperative blood loss, the complication rate, the number of secondary procedures,and implant failure between the reamed and unreamed groups were not statistically significant.Complications developed more frequently with proximal and distal fractures (p = 0.003).Comminution of the fracture itselfwas an important factor in fracture healing (p = 0.037), and insertionof a larger-diameter nail may have promoted bone consolidation by virtue of the increased stabilityachieved by the increased contact area between the implant and the bone surface (s = -2.48, p < 0.001).For simple or wedged mid-third tibia shaft fractures, interlocking intramedullarynailing, regardless ofwhether reaming is carried out, may produce satisfactory results. But for treatinghighly comminuted proximal or distal tibial shaft fractures, intramedullary reaming of the canal toaccommodate larger-diameter nails may facilitate fracture union.