Prader-Willi syndrome (PWS) patients can present with scoliosis which can be treated with serial cast correction (SCC) or with growth friendly surgery (GFS). This study’s purpose was to describe the results of SCC as well as GFS for PWS patients with early-onset scoliosis (EOS).
PWS patients were identified from 2 international multicenter EOS databases. Scoliosis, kyphosis, spine height (T1-S1), right/left hemithoracic heights/widths (RHTH, LHTH, RHTW, LHTW) were measured pretreatment, postoperation, and at 2-year follow-up. Complications were recorded.
Overall, 23 patients with 2-year follow-up were identified. Pretreatment; patients treated with SCC (n=10) had mean age of 1.8±0.6 years; body mass index (BMI), 16±1.5 kg/m2; scoliosis, 45±18 degrees; kyphosis, 56±9 degrees; T1-S1, 22.4±2.4 cm; RHTH, 8.0±2.0 cm; LHTH, 8.5±1.7 cm; RHTW, 6.6±1.3 cm; and LHTW, 8.0±1.0 cm. Patients treated with GFS (n=13) had mean age of 5.8±2.6 years; BMI, 21±5.4 kg/m2; scoliosis, 76±14 degrees; kyphosis, 59±25 degrees; T1-S1, 24.1±3.6 cm; RHTH, 10.0±1.6 cm; LHTH, 10.6±1.6 cm; RHTW, 9.4±2.5 cm; and LHTW, 8.1±2.8 cm. At 2-year follow-up, patients treated with SCC had mean scoliosis 37±11 degrees (18% correction, P=0.06); kyphosis, 42±6 degrees (NS); T1-S1, 26.4±2.1 cm (P<0.01); RHTH, 9.0±1.1 cm (13%; P=0.30); LHTH, 10.0±1.5 cm (18%, P<0.01); RHTW, 7.4±1.1 cm (12%, P<0.01); and LHTW, 8.0±1.0 cm (0%, P=0.34). At 2-year follow-up, patients treated with GFS had mean scoliosis 42±13 degrees (45% correction, P<0.000001); kyphosis, 53±13 degrees (10%, P=0.19); T1-S1, 31.5±5.4 cm (P<0.00001); RHTH, 12.0±2.4 cm (20%; P<0.01); LHTH, 12.0±1.7 cm (13%; P<0.01); RHTW, 9.8±1.3 cm (4%; P=0.27); and LHTW, 7.9±2.3 cm (3%;P=0.11). As an entire group, patients with a BMI>17 kg/m² had more device-related than disease-related complications (P=0.09). Patients treated with SCC had 0.9 complications per patient. Patients treated with GFS had 2.2 complications per patient [≤5 y more often had ≥2 complications (P=0.05)].
At 2-year follow-up, SCC and GFS were both effective in treating EOS in PWS patients. Patients treated with SCC had significant improvements in spine height and LHTH. Patients treated with GFS had significant improvements in scoliosis magnitude, spine height, RHTH, and LHTH.
Level IV—therapeutic study.
*IWK Health Centre
†Dalhousie University, Halifax, NS, Canada
‡Rady Children's Hospital, San Diego, CA
§Shriners Hospital for Children, Philadelphia
∥Children's Spine Foundation, Valley Forge, PA
J.O.: received funding from Dalhousie Faculty of Medicine’s Ross Stewart Smith Summer Studentship during the conduct of the study. B.C.: reports funding through Dalhousie Medical Research Foundation’s Lalia B Chase Summer Research Studentship during the conduct of the study. B.Y.: reports grants and personal fees from Depuy Synthes, personal fees from Nuvasive, grants and personal fees from K2M, personal fees from Globus, Medtronic, Stryker, and Orthopediatrics, outside the submitted work. A.S.: reports grants and nonfinancial support from DePuy Synthes Spine and other support from Children's Spine Study Group, during the conduct of the study; personal fees from DePuy Synthes Spine, Ethicon, Globus Medical, Misonix, Stryker, and Zimmer Biomet, other support from Setting Scoliosis Straight Foundation and Scoliosis Research Society outside the submitted work. R.E.-H.: reports personal fees from Depuy Synthes Spine, personal fees from Medtronic Spine, grants from Depuy Synthes Spine, grants from Medtronic Spine, personal fees from Apifix Ltd., other support from Children's Spine Foundation and Pediatric Orthopedic Society of North America, outside the submitted work. The Children’s Spine Study Group reports grants from DePuySynthes outside the submitted work. Growing Spine Study Group reports grants from Growing Spine Foundation during the conduct of the study; grants from Nuvasive, outside the submitted work; and The Growing Spine Foundation financially supports the Growing Spine Study Group, which provided the research data for this study. The GSF receives donations from the study group's surgeon members, medical device industry, grateful patients and other donors. The remaining authors declare no conflicts of interest.
Reprints: Ron El-Hawary, MD, IWK Health Centre, 5850 University Avenue, Halifax, NS, Canada B3K-6R8. E-mail: firstname.lastname@example.org.