In this paper we propose a new classification
of neurogenic peri-articular heterotopic ossification (HO) of the
hip based on three-dimensional (3D) CT, with the aim of improving
pre-operative planning for its excision. A total of 55 patients (73 hips) with clinically significant
HO after either traumatic brain or spinal cord injury were assessed
by 3D-CT scanning, and the results compared with the intra-operative
findings. At operation, the gross pathological anatomy of the HO as identified
by 3D-CT imaging was confirmed as affecting the peri-articular hip
muscles to a greater or lesser extent. We identified seven patterns
of involvement: four basic (anterior, medial, posterior and lateral)
and three mixed (anteromedial, posterolateral and circumferential).
Excellent intra- and inter-observer agreement, with kappa values
>
0.8, confirmed the reproducibility of the classification system. We describe the different surgical approaches used to excise
the HO which were guided by the 3D-CT findings. Resection was always
successful. 3D-CT imaging, complemented in some cases by angiography, allows
the surgeon to define the 3D anatomy of the HO accurately and to
plan its surgical excision with precision. Cite this article:
Pelvic discontinuity represents a rare but challenging
problem for orthopaedic surgeons. It is most commonly encountered
during revision total hip replacement, but can also result from
an iatrogentic acetabular fracture during hip replacement. The general
principles in management of pelvic discontinuity include restoration
of the continuity between the ilium and the ischium, typically with
some form of plating. Bone grafting is frequently required to restore
pelvic bone stock. The acetabular component is then impacted, typically
using an uncemented, trabecular metal component. Fixation with multiple
supplemental screws is performed. For larger defects, a so-called
‘cup–cage’ reconstruction, or a custom triflange implant may be
required. Pre-operative CT scanning can greatly assist in planning
and evaluating the remaining bone stock available for bony ingrowth.
Generally, good results have been reported for constructs that restore
stability to the pelvis and allow some form of biologic ingrowth. Cite this article: