Guarded Outcomes After Hip Hemiarthroplasty in Patients with Cerebral Palsy: Highlighting a Personalized Medicine Approach to Mitigate the Risk of Complications

Abstract

Background: The effectiveness of hip hemiarthroplasty in managing femoral neck fractures in individuals with cerebral palsy has seldom been reported. Objectives: Given the complex neuromuscular issues associated with cerebral palsy (CP), this retrospective study aims to document the outcomes and characterize the complications of hip hemiarthroplasty for fractures of the femoral neck in a series of patients with CP, emphasizing the role of precision medicine in management. Methods: Six cases of hip hemiarthroplasty in six male patients with cerebral palsy and displaced femoral neck fractures have been reviewed in this study. The patients' mean age at the time of surgery was 55.6 ± 14.1 years (range, 33-71). All the patients were independent indoor ambulators before their femoral neck fracture and had various medical comorbidities. Five patients had intellectual disabilities. Results: The mean clinical and radiographic follow-ups for the patients included in this series were 91.5 and 71.3 months, respectively. All the patients developed significant heterotopic ossification (HO) around the operated hip, which was observed as early as the second week postoperatively on radiographs. HO progressed throughout the follow-up for all the patients. One patient had an early postoperative dislocation with femoral stem loosening, which was managed by implant revision. Another patient had an acetabular protrusion, leading to the loss of their weight-bearing ability and mobility due to pain. Four patients were deceased at a mean of 86.5 months after the index surgery. Conclusions: After considering the preliminary evidence provided with this small case series, this study suggests the overall guarded outcomes of hip hemiarthroplasty in patients with CP. Given the 100% rate of heterotopic ossification, a precision medicine framework with consideration for HO prophylaxis may be recommended after hip hemiarthroplasty in patients with CP. It may also be reasonable to scrutinize a personalized risk assessment approach in this patient subset regarding decision making, surgical approach, and rehabilitation program. The clinical outcomes and the risks of complications following hemiarthroplasty should be sensibly presented to patients with cerebral palsy and their caregivers to achieve reasonable postoperative expectations.

Keywords: cerebral palsy; femoral neck; fracture; heterotopic ossification; hip hemiarthroplasty.

Figure 1

(A,B): Plain pelvis radiographs of a 71-year-old male with CP and a right valgus-impacted, ventrally tilted femoral neck fracture. The contralateral hip indicates an elevated femoral neck–shaft angle. (C,D): Plain pelvis radiographs of a 33-year-old male with CP and a left displaced femoral neck fracture. The contralateral femoral neck–shaft angle is increased as well.

Figure 2

(A,B) The plain hip radiographs of a 55-year-old man who presented with a displaced left femoral neck fracture. (C,D) Postoperative plain hip radiographs taken immediately after cemented bipolar hemiarthroplasty. (E) One-week postoperative plain pelvic radiographs showing dislocated HA and stem loosening. (F) Plain hip AP radiographs after open revision. (G) A plain hip radiograph taken one day postoperatively showing re-dislocation. (H) Closed reduction was performed. (I) A plain hip radiograph taken at 4 weeks after the initial HA surgery, showing early HO lateral to the acetabular margin, along with stable HA components. (J) Eight-week and (K) 40-month postoperative plain radiographs showing progressive heterotopic ossification (HO). (L,M) Seventy-two-month postoperative radiographs showing class 3 acetabular and proximal femoral HO.

Figure 3

(A) The plain hip X-rays of a 47-year-old man with a displaced left femoral neck fracture. (B) Postoperative plain hip radiographs taken immediately following cementless bipolar hemiarthroplasty. (C,D) Twenty-two-month postoperative plain radiographs and CT scans of the pelvis, showing HO and radiographic acetabular erosion. (E,F) Postoperative plain hip radiographs at 61.6 months, showing HO and acetabular erosion progression. (G–J) X-rays and CT scan images taken approximately 177 months postoperatively (axial [H] and sagittal [I], and coronal [J]) showing an almost completely fused hip with class 4 HO and acetabular protrusion.

Figure 4

(A) The plain hip radiographs of a 68-year-old man who presented with a displaced right femoral neck fracture. (B) Postoperative plain hip radiograph taken immediately after cemented bipolar hemiarthroplasty. (C) Two-week postoperative plain pelvic radiograph showing stable HA and early HO. (D,E) Seventeen-month postoperative plain hip AP radiographs showing class 4 HO.