Finding consensus for hamstring surgery in ambulatory children with cerebral palsy using the Delphi method.

Purpose: There is marked variation in indications and techniques for hamstring surgery in children with cerebral palsy. There is particular uncertainty regarding the indications for hamstring transfer compared to traditional hamstring lengthening. The purpose of this study was for an international panel of experts to use the Delphi method to establish consensus indications for hamstring surgery in ambulatory children with cerebral palsy. Methods: The panel used a five-level Likert-type scale to record agreement or disagreement with statements regarding hamstring surgery, including surgical indications and techniques, post-operative care, and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert-type ratings. General agreement was defined as 60%-79% falling into the highest or lowest two ratings. There was no agreement if neither of these thresholds was reached. Results: The panel reached consensus or general agreement for 38 (84%) of 45 statements regarding hamstring surgery. The panel noted the importance of assessing pelvic tilt during gait when considering hamstring surgery, and also that lateral hamstring lengthening is rarely needed, particularly at the index surgery. They noted that repeat hamstring lengthening often has poor outcomes. The panel was divided regarding hamstring transfer surgery, with only half performing such surgery. Conclusion: The results of this study can help pediatric orthopedic surgeons optimize decision-making in their choice and practice of hamstring surgery for ambulatory children with cerebral palsy. This has the potential to reduce practice variation and significantly improve outcomes for ambulatory children with cerebral palsy. Level of evidence: level V.

Anterior distal femoral hemiepiphysiodesis in children with cerebral palsy: Establishing surgical indications and techniques using the modified Delphi method and literature review.

Purpose: The purpose of this study was to develop consensus for the surgical indications of anterior distal femur hemiepiphysiodesis in children with cerebral palsy using expert surgeon opinion through a modified Delphi technique. Methods: The panel used a 5-level Likert-type scale to record agreement or disagreement with 27 statements regarding anterior distal femur hemiepiphysiodesis. Consensus was defined as at least 80% of responses being in the highest or lowest 2 of the Likert-type ratings. General agreement was defined as 60%-79% falling into the highest or lowest 2 ratings. Results: For anterior distal femur hemiepiphysiodesis, 27 statements were surveyed: consensus or general agreement among the panelists was achieved for 22 of 27 statements (22/27, 82%) and 5 statements had no agreement (5/27, 18%). There was general consensus that anterior distal femur hemiepiphysiodesis is indicated for ambulatory children with cerebral palsy, with at least 2 years growth remaining, and smaller (<30 degrees) knee flexion contractures and for minimally ambulatory children to aid in standing/transfers. Consensus was achieved regarding the importance of close radiographic follow-up after screw insertion to identify or prevent secondary deformity. There was general agreement that percutaneous screws are preferred over anterior plates due to the pain and irritation associated with plates. Finally, it was agreed that anterior distal femur hemiepiphysiodesis was not indicated in the absence of a knee flexion contracture. Conclusion: Anterior distal femur hemiepiphysiodesis can be used to treat fixed knee flexion contractures in the setting of crouch gait, but other associated lever arm dysfunctions must be addressed by single-event multilevel surgery. Level of evidence: V.

Establishing surgical indications for hamstring lengthening and femoral derotational osteotomy in ambulatory children with cerebral palsy.

PURPOSE: Surgical procedures, such as medial hamstring lengthening (MHL) and femoral derotational osteotomy (FDO), can improve the gait of children with cerebral palsy (CP); however, substantial variation exists in the factors that influence the decision to perform surgery. The purpose of this study was to use expert surgeon opinion through a Delphi technique to establish consensus for indications in ambulatory children with CP. METHODS: A 15-member panel, all established experts with at least nine years' experience in the surgical management of children with CP, was created (mean of 20.81 years' experience). All panel members also had expertise of the use of movement analysis for the assessment of gait disorders in children with CP. The group initially focused on two of the most commonly performed procedures, MHL and FDO, in an attempt to gain consensus (> 80%). This was obtained through a standardized, iterative Delphi process. RESULTS: For MHL, a total of 59 questions were surveyed: 41 indication questions and 18 outcome questions, for which there was consensus on ten indication questions and seven outcomes. For FDO, a total of 55 questions were surveyed: 43 indication questions and 12 outcome questions, for which there was consensus on 29 indication questions and eight outcomes. CONCLUSION: This study is the first to use an expert panel to identify best-practice indications for common surgical procedures of children with CP. The results from this study will allow for more informed evaluation of practice and form the basis for future improvement efforts to standardize surgical recommendations internationally. LEVEL OF EVIDENCE: Level IV.

Modeling of the naked facet sign in the lumbar spine.

The study design is a computer visualization model that simulated flexion deformities about the lumbar spine for evaluation of the naked facet sign (NFS). The objectives were to ascertain the angles of rotation required for NFS to occur in the lumbar spine with various centers of rotation about the vertebral body and to assess whether NFS correlates with unstable flexion-distraction injuries in the lumbar spine. The presence of the NFS on axial computed tomography (CT) images occurs when the inferior articulating facet of the cephalad vertebra is not paired with an adjacent superior articulating facet of the caudal vertebra. This sign, when evidenced in the lumbar spine, is suggestive of significant injury secondary to a flexion-distraction force. A previous study using a computer-generated spine model challenged the utility of the NFS in the thoracolumbar spine. The NFS may prove to be more diagnostic of an unstable injury in the lumbar spine because of its normal lordotic resting position. A commercial spine computer visualization model was used to simulate various degrees of flexion injury in the lumbar spine. Lumbar functional spinal units (FSU) L2-L5 were each examined separately. The model simulated two CT scan slices (each 2 mm thick), which were created parallel to the inferior endplate of the cephalad vertebra of each FSU. The cephalad vertebra was rotated in 0.5 degrees increments until NFS was produced. The appearance of NFS required >/=11 degrees kyphotic angulation in more than two thirds of simulated centers of rotation about the lumbar vertebral bodies. The NFS was produced between a range of 8-24.5 degrees. For rotations about a point located 3 cm anterior to the vertebral body (to simulate seat-belt-type flexion-distraction injuries), the minimum angle required for NFS was 7.5 degrees. Our data correlate well with previously published results from in vitro and cadaveric studies. As opposed to the thoracolumbar spine, which normally rests in a neutral position, the lumbar spine normally rests in a lordotic position. Therefore, NFS in the lumbar spine may be more suggestive of an unstable injury and would warrant closer examination of the patient and additional radiographic studies.