Spondyloepiphyseal dysplasia (SED) is rare genetic condition which leads to skeletal and joint deformities that can predispose patients to degenerative joint disease. There are limited reports on the results of total hip arthroplasty (THA) in this patient population. The purpose of this study is to review clinical and radiographic outcomes of THA performed in patients with SED at one institution.
Among 43,917 patients undergoing primary THA from 1970 to 2015, we identified 50 THAs performed in 29 patients with SED; 21 patients underwent bilateral THA (none simultaneous). There were 16 females and 13 males; mean age, body mass index, and height were 39 years, 28.7 kg/m2, and 145 cm, respectively. All patients were able to ambulate prior to the THA. Mean follow-up was 11 years (range 2-38).
Mean implant survival for primary THA in SED patients at the 5, 10, and 20-year time points was 96%, 85%, and 55%, respectively. Thirteen patients required revision THA, most commonly for polyethylene wear (n = 6) and aseptic loosening (n = 5), and 4 additional patients underwent nonrevision reoperations. Prior to surgery, 90% of patients had severe or moderate pain, which was reduced to 8% of patients postoperatively (P < .001). Mean Harris Hip Score improved from 47 to 87 (P < .001). Prior to surgery, 64% of patients required gait aids, which reduced to 34% postoperatively (P < .001).
THA provided significant pain reduction and improvement in function, with a majority of patients ambulating independently following the procedure. There was a high incidence of complications following THA in patients with SED, most commonly secondary to polyethylene wear and osteolysis from conventional polyethylene and historical implants.
Level IV, Therapy.

Type 2 collagen disorders encompass a diverse group of skeletal dysplasias that are commonly associated with orthopedic, ocular, and hearing problems. However, the frequency of many clinical features has never been determined. We retrospectively investigated the clinical, radiological, and genotypic data in a group of 93 patients with molecularly confirmed SEDC or a related disorder. The majority of the patients (80/93) had short stature, with radiological features of SEDC (n = 64), others having SEMD (n = 5), Kniest dysplasia (n = 7), spondyloperipheral dysplasia (n = 2), or Torrance-like dysplasia (n = 2). The remaining 13 patients had normal stature with mild SED, Stickler-like syndrome or multiple epiphyseal dysplasia. Over 50% of the patients had undergone orthopedic surgery, usually for scoliosis, femoral osteotomy or hip replacement. Odontoid hypoplasia was present in 56% (95% CI 38-74) and a correlation between odontoid hypoplasia and short stature was observed. Atlanto-axial instability, was observed in 5 of the 18 patients (28%, 95% CI 10-54) in whom flexion-extension films of the cervical spine were available; however, it was rarely accompanied by myelopathy. Myopia was found in 45% (95% CI 35-56), and retinal detachment had occurred in 12% (95% CI 6-21; median age 14 years; youngest age 3.5 years). Thirty-two patients complained of hearing loss (37%, 95% CI 27-48) of whom 17 required hearing aids. The ophthalmological features and possibly also hearing loss are often relatively frequent and severe in patients with splicing mutations. Based on clinical findings, age at onset and genotype-phenotype correlations in this cohort, we propose guidelines for the management and follow-up in this group of disorders.