Hip osteoarthritis is prevalent in 8% to 28% of patients with Down syndrome. Presence of disabling hip pain is increased along with prolonged life expectancy, suggesting total hip arthroplasty (THA). Seven consecutive patients (9 hips) with Down syndrome underwent primary THA. Coxarthrosis was secondary to developmental hip dysplasia in 6 patients and slipped capital epiphysis in 1 patient. In 5 patients (7 hips), a previous hip surgery was performed. Average clinical and radiological follow-up was 9.9±6.4 years (range, 2-22.5 years; median, 9.3 years). Average patient age at THA was 34.8±7.5 years (range, 25- 47 years; median, 35.4 years). In 2 patients (3 hips), a trochanteric slide was used for the surgical approach, while a lateral transgluteal approach was used in the remaining patients. One-way analysis of variance test was used to compare Harris Hip Scores at postoperative follow-up.
Harris Hip Scores improved significantly (P=.008) from 4.1±15.1 (range, 18.5-65; median, 45) to 84.8.3±7.7 (range, 70-93; median, 85.8) at 4-year follow-up. Harris Hip Scores (average, 70.9±6.2; range, 66.5-80; median, 68) remained essentially unchanged (P=.43) at 8-year follow-up. Two patients required revision THA for stem loosening at 6 and 16 years post-THA, respectively. The first patient is 7 years post-revision and ambulates without aids. The second patient is 6.1 years post-revision and ambulates with a walker. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered. At last follow-up, all patients had a functional range of motion without evidence of discomfort related to their THA.
Down syndrome is the most common chromosomal disorder, occurring in an estimated 550 infant births annually in the United States.1 Apart from intellectual disability, patients with Down syndrome are prone to ligamentous hyperlaxity and muscle hypotonia affecting the cervical spine, knees, and hips.2 Hip abnormalities include coxa valga and acetabular dysplasia.2 With a prolonged life expectancy, disabling hip pain is now more frequently encountered.3 However, surgeons may be deterred from performing total hip arthroplasty (THA) in patients with Down syndrome due to their younger age and inability to adhere to hip precautions.3,4
Materials and Methods
The study group comprised 7 consecutive patients (9 hips) with Down syndrome and symptomatic hip osteoarthritis that interfered with their activities of daily living. In all patients, primary THA was performed under the supervision of the senior author (A.E.G.) over a period of 2 decades.
Collarless, proximally porous-coated, cementless femoral stems and hemispheric porous-coated, cementless cups secured with screws were used in all patients (Figures 1, 2). In 6 of the THAs, a constrained liner was used to enhance stability due to soft tissue hyperlaxity and patients’ anticipated lack of compliance.
| || |
| Figure 1: Preoperative radiograph showing bilateral dysplasia with osteoarthritic hips in a patient with Down syndrome. Figure 2: Five-year postoperative radiograph showing bilateral uncemented hip replacements with constrained cups and a left acetabular shelf graft. |
Average patient age at surgery was 34.8±7.5 years (range, 25-47 years) with a mean follow-up of 9.9±6.4 years (range, 2-22.3 years). Follow-up consisted of clinical evaluations using Harris Hip Scores (HHS) and radiographic examination at standard postoperative intervals. Radiographs were evaluated by 2 of the authors (A.E.G., Y.K.) for evidence for component migration or loosening.5,6
Harris Hip Scores improved significantly (P=.008) from 4.1±15.1 (range, 18.5-65; median, 45) to 84.8.3±7.7 (range, 70-93; median, 85.8) at 4-year follow-up. Harris Hip Scores (average, 70.9±6.2; range, 66.5-80; median, 68) remained essentially unchanged (P=.43) at 8-year follow-up. Two patients required revision THA for stem loosening at 6 and 16 years post-THA, respectively. The first patient is 7 years post-revision and ambulates without aids. The second patient is 6.1 years post-revision and ambulates with a walker. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered.
There were no complications related to anesthesia. At last follow-up, all patients had a functional range of motion without evidence of discomfort related to their THA.
Hip osteoarthritis is a significant problem in Down syndrome patients, with a prevalence of 8% to 28%.2 Patients with Down syndrome require careful medical, social, and orthopedic preoperative evaluation and preparation.4 Total hip arthroplasty in these patients may be relatively more demanding surgically due to the presence of bony deformities typical for developmental dysplasia of the hip, affecting both acetabulum and femur, including deformed femoral neck, narrow femoral canal, and deficient acetabulum. In addition, soft tissue hyperlaxity may compromise postoperative stability, especially if smaller-sized femoral heads are to be used.
Thus, appropriate THA designs, including smaller-sized stems to fit the narrow femoral canal and metallic augments or structural bone autograft to support the acetabular cup, should be available to allow the surgeon to address these challenges. In complex cases, modified trochanteric slide to facilitate surgical exposure is advised. Constrained liners can be used to enhance stability, especially when tissue hyperlaxity is encountered in less compliant patients. External stabilizers such as spica or abduction braces are not required.
Based on the current results, we contend that THA is a reliable, well-tolerated surgical intervention in patients with Down syndrome and symptomatic coxarthrosis. With appropriate patient selection, this group can be expected to have long-term pain relief and good mobility following THA.
- Stoll C, Alembik Y, Dott B, Roth MP. Study of Down syndrome in 238,942 consecutive births. Ann Genet. 1998; 41(1):44-51.
- Shaw ED, Beals RK. The hip joint in Down’s syndrome. A study of its structure and associated disease. Clin Orthop Relat Res. 1992; (278):101-107.
- Hresko MT, McCarthy JC, Goldberg MJ. Hip disease in adults with Down syndrome. J Bone Joint Surg Br. 1993; 75(4):604-607.
- Skoff HD, Keggi K. Total hip replacement in Down’s syndrome. Orthopedics. 1987; 10(3):485-489.
- Massin P, Schmidt L, Engh CA. Evaluation of cementless acetabular component migration. An experimental study. J Arthroplasty. 1989; 4(3):245-251.
- Kim YH, Kim JS, Oh SH, Kim JM. Comparison of porous-coated titanium femoral stems with and without hydroxyapatite coating. J Bone Joint Surg Am. 2003; 85(9):1682-1688.
Drs Kosashvili, Backstein, Safir, Gross, and Lakstein and Mr Taylor are from the Department of Surgery, Division of Orthopedic Surgery, Mount Sinai Hospital, Toronto, Ontario, Canada.
Drs Kosashvili, Backstein, Safir, Gross, and Lakstein and Mr Taylor have no relevant financial relationships to disclose.
Presented at Current Concepts in Joint Replacement 2009 Winter Meeting; December 9-12, 2009; Orlando, Florida.
Correspondence should be addressed to: Allan Gross, MD, FRCS(C), Department of Surgery, Division of Orthopedic Surgery, Mount Sinai Hospital, 600 University Ave, Ste 476A, Toronto, Ontario, M5G 1X5 Canada (firstname.lastname@example.org).