Kulkarni Vedant A, Boyles Aaron D, Carl Jacob, Boakes Jennette L, Wilson Benjamin, Bagley Anita M, Muchow Ryan D
Shriners Hospitals for Children-Northern California and UC Davis Medical Center, Sacramento, CA.
Shriners Hospitals for Children Lexington, Lexington, KY.
J Pediatr Orthop. 2020 Aug;40(7):e592-e597. doi: 10.1097/BPO.0000000000001552.
This study assesses the effect of skeletal maturity on the development of iatrogenic proximal femoral deformity following threaded prophylactic screw fixation in patients presenting with unilateral slipped capital femoral epiphysis (SCFE).
Children who underwent threaded screw prophylaxis of the uninvolved hip (Group P) and those who were observed with no prophylaxis (Group N) on presentation with unilateral SCFE were compared. Skeletal maturity was assessed with the Modified Oxford Score (MOS). Proximal femoral morphology was characterized by femoral neck length, femoral neck width, neck shaft angle, and trochanteric femoral head overlap percentage (TFHOP). Femoral head deformity at final follow-up was characterized as spherical (Type 1), mildly aspherical (Type 2), or ovoid (Type 3). Analysis of variance and t test were used to compare the groups.
Thirty-eight patients in Group P and 17 patients in Group N met inclusion criteria. The average follow-up was 2.6 years. Group P was younger than Group N by an average of 9.6 months (P=0.04), but the MOS for skeletal maturity was not different between groups (P=0.15). Group P had significantly diminished neck length (P=0.008) and significantly increased relative trochanteric overgrowth as evidenced by increased trochanteric femoral head overlap percentage (P<0.001), but there was no difference between groups in neck shaft angle and neck width. No patient in Group N developed femoral head deformity (all Type 1). In Group P, 14 patients (37%) developed Types 2 and 3 deformity. In patients with MOS 16 in Group P, 60% (3/5) developed Type 2 deformity and 40% (2/5) developed Type 3 deformity. In patients with MOS 17 in Group P, 45% (5/11) had Type 2 deformity.
Skeletally immature patients with an MOS of 16 and 17 are at high risk for developing the triad of relative trochanteric overgrowth, coxa breva, and femoral head asphericity with prophylactic threaded screw fixation for SCFE. When prophylactic surgery is indicated, consideration should be given to growth friendly fixation strategies to avoid iatrogenic proximal femoral deformity.
Level III-therapeutic retrospective comparative study.
本研究评估了骨骼成熟度对单侧股骨头骨骺滑脱（SCFE）患者采用带螺纹预防性螺钉固定后医源性股骨近端畸形发展的影响。
比较了单侧SCFE患者中接受未受累髋关节带螺纹螺钉预防性固定的儿童（P组）和未进行预防性固定而接受观察的儿童（N组）。采用改良牛津评分（MOS）评估骨骼成熟度。股骨近端形态通过股骨颈长度、股骨颈宽度、颈干角和股骨转子股骨头重叠百分比（TFHOP）进行表征。末次随访时的股骨头畸形分为球形（1型）、轻度非球形（2型）或卵形（3型）。采用方差分析和t检验对两组进行比较。
P组38例患者和N组17例患者符合纳入标准。平均随访时间为2.6年。P组比N组平均年轻9.6个月（P = 0.04），但两组骨骼成熟度的MOS无差异（P = 0.15）。P组的颈长度显著缩短（P = 0.008），股骨转子相对过度生长显著增加，表现为股骨转子股骨头重叠百分比增加（P < 0.001），但两组在颈干角和颈宽度方面无差异。N组无患者发生股骨头畸形（均为1型）。P组中,14例患者（37%）发生2型和3型畸形。P组中MOS为16的患者，60%（3/5）发生2型畸形，40%（2/5）发生3型畸形。P组中MOS为17的患者，45%（5/11）发生2型畸形。
MOS为16和17的骨骼未成熟患者，采用SCFE预防性带螺纹螺钉固定时，发生股骨转子相对过度生长、髋内翻和股骨头非球形三联征的风险较高。当需要进行预防性手术时，应考虑采用有利于生长的固定策略，以避免医源性股骨近端畸形。
III级——治疗性回顾性对比研究。
