Statz, Joseph M.

Background: Historically, total hip arthroplasty (THA) performed in patients ≤20 years old has been associated with poor survivorship because of bearing-surface wear with conventional polyethylene, acetabular loosening with cemented sockets, and liner fracture in ceramic-on-ceramic (CoC) THA. For this population, there is a paucity of data regarding outcomes of THAs performed with use of modern implants and bearing surfaces. The purpose of the present study was to examine the mid- to long-term outcomes of modern THA in patients ≤20 years old. Methods: Utilizing a single-institution, prospectively collected total joint registry, we retrospectively identified 91 primary THAs performed in 78 patients ≤20 years old from 1998 to 2016. The average patient age was 17 years (range, 11 to 20 years), and the average body mass index was 26 kg/m 2 (range, 16 to 49 kg/m 2 ). Forty-eight THAs (53%) were performed in male patients, and 47 (52%) were performed on the right hip. Bearing surfaces included CoC (53 THAs, 58%), metal-on-highly cross-linked polyethylene (MoP; 28 THAs, 31%), and ceramic-on-highly cross-linked polyethylene (CoP; 10 THAs, 11%). Outcome measures included reoperations, revisions, complications, clinical outcome scores, and bearing-surface wear. Results: At an average follow-up of 8 years (range, 2 to 18 years), the average modified Harris hip score was 92 (range, 54 to 100), and 95% of patients reported feeling “much better” following the surgical procedure. Survivorship at 2, 5, and 10 years postoperatively was 96.7%, 96.7%, and 95.0% for reoperation; 98.9%, 98.9%, and 97.2% for revision; and 91.2%, 91.2%, and 89.5% for complications, respectively. The most common complications were instability (3 THAs, 3%), aseptic acetabular loosening (2 THAs, 2%), and postoperative foot drop (2 THAs, 2%). Linear articular wear averaged 0.019 mm/yr. There were no correlations between age, sex, body mass index, bearing surface, femoral head size, use of cement, or operative time and survivorship from complications, reoperations, or revisions. There were no differences in linear wear among CoC, CoP, and MoP bearing surfaces. Conclusions: In patients ≤20 years old, THAs performed with use of modern implants exhibit excellent clinical outcome scores and survivorship at mid- to long-term follow-up. CoC, CoP, and MoP bearing surfaces have similar survivorship, clinical outcomes, and bearing-surface wear in this population. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Background: Periacetabular osteotomy (PAO) can be used for joint preservation in symptomatic developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI). 1 of the most common procedures following PAO is hardware removal. The aims of this study were to determine the rate of hardware removal and patient characteristics associated with this outcome following PAO. Methods: Data from a prospectively-collected registry was retrospectively reviewed at one institution managing DDH or FAI patients with PAO from July 2008–December 2015. Patients who completed preoperative and postoperative patient reported outcome (PRO) questionnaires with minimum 1-year follow-up were evaluated, resulting in 221 patients followed for a mean of 2.8 years (range 1.0–7.7 years). There were 80% women, mean age was 25 years and mean body mass index (BMI) was 25 kg/m 2 . Fully-threaded 4.5-mm screws were used for internal fixation. Results: Hardware removal occurred in 30 patients (13.6%) at a mean of 1.0 years after PAO. Patients undergoing hardware removal were younger (mean age 20.4 vs. 26.3 years), thinner (mean BMI 22.2 vs. 25.1), had less severe dysplasia (DDH patients only: mean lateral centre-edge angle 21.0 vs. 16.2, mean Tönnis angle 12.9 vs. 16.8), and were more likely to have PAO for FAI (33% vs. 11%) compared to patients with retained hardware. At final follow-up, multivariable analysis demonstrated a trend toward inferior patient reported outcomes in the hardware removal group. Conclusions: This study defines the incidence and characteristics of patients undergoing hardware removal after PAO and demonstrates similar outcomes to patients who do not require hardware removal.

» Patients with neuromuscular spasticity about the hip with concomitant painful hip arthritis can be effectively treated with total hip arthroplasty, with excellent clinical outcomes and durable implant survivorship. » Certain subsets of patients in this population are at increased risk of dislocation, component loosening, and heterotopic ossification and are also prone to postoperative medical complications. » Strategies that may mitigate the risk of dislocation include using large femoral heads or dual-mobility articulations with cautious use of constrained liners, careful repairing of soft-tissue structures at the conclusion of the surgical procedure, and performing concomitant adductor and flexor tenotomies. In addition, the other common complications can be reduced by coordinating perioperative care with neurological and medical specialists and administering perioperative heterotopic ossification prophylaxis, most commonly in the form of nonsteroidal anti-inflammatory medications, if tolerated.