Department of Orthopaedic Surgery, Yale University, New Haven, Connecticut.
Division of Orthopaedic Surgery, The Ottawa Hospital, Ontario, Canada; Department of Orthopaedic and Trauma Surgery, University of Heidelberg, Heidelberg, Germany.
J Arthroplasty. 2024 Sep;39(9S2):S293-S300. doi: 10.1016/j.arth.2024.02.079. Epub 2024 Mar 8.
Spinopelvic characteristics, including sacral slope (SS), are commonly evaluated in different positions pre-total hip arthroplasty (THA). This study aimed to: 1) investigate the change in spinopelvic parameters at 7 days (early) and 1-year post-THA; and 2) identify patient characteristics associated with a change in SS of more than 7° post-THA.
We prospectively studied 250 patients who underwent unilateral THA [132 women, age 66 years (range, 32 to 88)] and underwent biplanar images preoperatively and at 7 days and 1-year post-THA. Parameters measured included pelvic incidence, standing lumbar lordosis, SS, and proximal femoral angle (PFA). A SS change ≥ 7° was considered the threshold as it would result in more than a 5° change in cup orientation.
Early post-THA SS remained within ± 6º from preoperative measurements in 75% of patients, reduced by ≥ 7° in 9%, and increased by ≥ 7° in 16%. Those that showed a reduction in SS had the lowest PFA and the highest SS pre-THA (P = .028, .107, and < 0.001, respectively). From 7 days until the 1-year mark, pelvic tilt increased, SS reduced (mean: -4º, range: -29 to 17º, P < .001), and patients stood with greater hip extension ΔPFA (mean 7°, range: -34 to 37°, P < .001). At 1 year, SS had remained within ± 6º, relative to the pre-THA value, in 49% of patients.
Standing spinopelvic characteristics, especially SS remain within ±6° in three-quarters of patients both early- and at 1-year post-THA. In the remaining cases, pelvic tilt changes significantly. In 9% of cases, SS reduces ≥ 7° early THA, probably due to the alleviation of fixed-flexion contractures. The SS changes by ≥ ± 7° in almost 50% of cases in this study, and its clinical value as a preoperative planning tool should be questioned.
Level II, diagnostic study.
在全髋关节置换术（THA）前，通常会评估脊柱骨盆特征，包括骶骨倾斜角（SS），在不同体位下进行。本研究旨在：1）研究 THA 后 7 天（早期）和 1 年时脊柱骨盆参数的变化；2）确定与 THA 后 SS 变化超过 7°相关的患者特征。
我们前瞻性研究了 250 例接受单侧 THA 的患者[132 例女性，年龄 66 岁（范围 32 至 88 岁）]，并在术前、术后 7 天和 1 年进行双平面成像。测量的参数包括骨盆入射角、站立腰椎前凸角、SS 和股骨近端角（PFA）。SS 变化≥7°被认为是一个阈值，因为它会导致杯位取向改变超过 5°。
75%的患者术后早期 SS 与术前测量值相差±6°以内，9%的患者 SS 减少≥7°，16%的患者 SS 增加≥7°。SS 减少的患者 PFA 最低，THA 前 SS 最高（P=0.028，0.107 和<0.001）。从术后 7 天到 1 年，骨盆倾斜增加，SS 减少（平均：-4°，范围：-29 至 17°，P<0.001），患者站立时髋关节伸展增加 ΔPFA（平均 7°，范围：-34 至 37°，P<0.001）。1 年后，SS 与术前值相比，仍在±6°以内的患者占 49%。
站立脊柱骨盆特征，尤其是 SS，在 THA 后早期和 1 年时，75%的患者仍在±6°以内。在其余病例中，骨盆倾斜明显改变。9%的病例在 THA 早期 SS 减少≥7°，可能是由于固定屈曲挛缩的缓解。本研究中，几乎有 50%的病例 SS 变化超过±7°，其作为术前规划工具的临床价值值得怀疑。
II 级，诊断研究。
