Walter Reed National Military Medical Center, Department of Orthopaedic Surgery, Bethesda, Maryland, USA.
Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, Maryland, USA.
Am J Sports Med. 2022 Sep;50(11):3028-3035. doi: 10.1177/03635465221115828. Epub 2022 Aug 19.
Although posterior glenohumeral instability is becoming an increasingly recognized cause of shoulder pain, the role of posterior glenoid bone loss on outcomes remains incompletely understood.
To prospectively determine the amount of bone loss associated with posterior instability events and to determine predisposing factors based on preinstability imaging.
Cross-sectional study; Level of evidence, 3.
A total of 1428 shoulders were evaluated prospectively for ≥4 years. At baseline, a subjective history of shoulder instability was ascertained for each patient, and bilateral noncontrast magnetic resonance imaging (MRI) scans of the shoulders were obtained regardless of any reported history of shoulder instability. The cohort was prospectively followed during the study period, and those who were diagnosed with posterior glenohumeral instability were identified. Postinjury MRI scans were obtained and compared with the screening MRI scans. Glenoid version, perfect-circle-based bone loss was measured for each patient's pre- and postinjury MRI scans using previously described methods.
Of the 1428 shoulders that were prospectively followed, 10 shoulders sustained a first-time posterior instability event and 3 shoulders sustained a recurrent posterior instability event. At baseline, 11 of 13 shoulders had some amount of glenoid dysplasia and/or bone loss. The change in glenoid bone loss was 5.4% along the axis of greatest loss (95% CI, 3.8%-7.0%; = .009), 4.4% at the glenoid equator (95% CI, 2.7%-6.2%; = .016), and 4.2% of total glenoid area (95% CI, 2.9%-5.3%; = .002). Recurrent glenoid instability was associated with a greater amount of absolute bone loss along the axis of greatest loss compared with first-time instability (recurrent: 16.8% ± 1.1%; 95% CI, 14.6%-18.9%; first-time: 10.0% ± 1.5%; 95% CI, 7.0%-13.0%; = .005). Baseline glenoid retroversion ≥10° was associated with a significantly greater percentage of bone loss along the axis of greatest loss (≥10° of retroversion: 13.5% ± 2.0%; 95% CI, 9.6%-17.4%; <10° of retroversion: 8.5% ± 0.8%; 95% CI, 7.0%-10.0%; = .045).
Posterior glenohumeral instability events were associated with glenoid bone loss of 5%. The amount of glenoid bone loss after a recurrent posterior glenohumeral instability event was greater than that after first-time instability. Glenoid retroversion ≥10° was associated with a greater amount of posterior glenoid bone loss after a posterior instability event.
尽管后方盂肱关节不稳定已成为肩部疼痛日益被认识的一个原因，但后方关节盂骨量丢失对预后的影响仍不完全清楚。
前瞻性确定与后方不稳定事件相关的骨丢失量，并根据不稳定前的影像学检查确定易患因素。
前瞻性研究；证据水平，3 级。
前瞻性评估了 1428 例肩部≥4 年。在基线时，对每位患者进行了肩部不稳定的主观病史评估，无论是否有肩部不稳定的报告病史，均获得双侧非对比性磁共振成像（MRI）扫描。在研究期间对该队列进行了前瞻性随访，并确定了诊断为后方盂肱关节不稳定的患者。获得损伤后的 MRI 扫描，并与筛选性 MRI 扫描进行比较。使用先前描述的方法，对每位患者的损伤前和损伤后的 MRI 扫描进行基于完美圆形的关节盂版本和骨丢失测量。
在 1428 例前瞻性随访的肩部中，有 10 例发生了首次后方不稳定事件，3 例发生了复发性后方不稳定事件。在基线时，13 例肩部中有 11 例存在某种程度的关节盂发育不良和/或骨丢失。关节盂骨丢失的变化沿最大丢失轴为 5.4%（95%CI，3.8%-7.0%； =.009），在关节盂赤道处为 4.4%（95%CI，2.7%-6.2%； =.016），在整个关节盂区域为 4.2%（95%CI，2.9%-5.3%； =.002）。复发性关节盂不稳定与最大丢失轴上的绝对骨丢失量较首次不稳定明显更大（复发性：16.8%±1.1%；95%CI，14.6%-18.9%；首次：10.0%±1.5%；95%CI，7.0%-13.0%； =.005）。基线时关节盂后倾≥10°与沿最大丢失轴的骨丢失百分比显著相关（后倾≥10°：13.5%±2.0%；95%CI，9.6%-17.4%；后倾<10°：8.5%±0.8%；95%CI，7.0%-10.0%； =.045）。
后方盂肱关节不稳定事件与关节盂骨丢失 5%相关。复发性后方盂肱关节不稳定事件后关节盂骨丢失量大于首次不稳定事件后。关节盂后倾≥10°与后方不稳定事件后关节盂后方骨丢失量增加相关。
