Effects of Virtual Exercise Rehabilitation In-Home Therapy Compared with Traditional Care After Total Knee Arthroplasty: VERITAS, a Randomized Controlled Trial.

BACKGROUND: Financial burden for patients, providers, and payers can reduce access to physical therapy (PT) after total knee arthroplasty (TKA). The purpose of the present study was to examine the effect of a virtual PT program on health-care costs and clinical outcomes as compared with traditional care after TKA. METHODS: At least 10 days before unilateral TKA, patients from 4 clinical sites were enrolled and randomized 1:1 to the virtual PT program (involving an avatar [digitally simulated] coach, in-home 3-dimensional biometrics, and telerehabilitation with remote clinician oversight by a physical therapist) or to traditional PT care in the home or outpatient clinic. The primary outcome was total health-care costs for the 12-week post-hospital period. Secondary (noninferiority) outcomes included 6 and 12-week Knee injury and Osteoarthritis Outcome Score (KOOS); 6-week knee extension, knee flexion, and gait speed; and 12-week safety measures (patient-reported falls, pain, and hospital readmissions). All outcomes were analyzed on a modified intent-to-treat basis. RESULTS: Of 306 patients (mean age, 65 years; 62.5% women) who were randomized from November 2016 to November 2017, 290 had TKA and 287 (including 143 in the virtual PT group and 144 in the usual care group) completed the trial. Virtual PT had lower costs at 12 weeks after discharge than usual care (median, $1,050 compared with $2,805; p < 0.001). Mean costs were $2,745 lower for virtual PT patients. Virtual PT patients had fewer rehospitalizations than the usual care group (12 compared with 30; p = 0.007). Virtual PT was noninferior to usual PT in terms of the KOOS at 6 weeks (difference, 0.77; 90% confidence interval [CI], -1.68 to 3.23) and 12 weeks (difference, -2.33; 90% CI, -4.98 to 0.31). Virtual PT was also noninferior to usual care at 6 weeks in terms of knee extension, knee flexion, and gait speed and at 12 weeks in terms of pain and hospital readmissions. Falls were reported by 19.4% of virtual PT patients and 14.6% of usual care patients (difference, 4.83%; 90% CI, -2.60 to 12.25). CONCLUSIONS: Relative to traditional home or clinic PT, virtual PT with telerehabilitation for skilled clinical oversight significantly lowered 3-month health-care costs after TKA while providing similar effectiveness. These findings have important implications for patients, health systems, and payers. Virtual PT with clinical oversight should be considered for patients managed with TKA. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Modular insert exchange in knee arthroplasty for treatment of wear and osteolysis.

UNLABELLED: Wear and osteolysis have been successfully treated by modular polyethylene exchange in revision hip arthroplasty. However, studies of the same approach in revision knee arthroplasty have not provided similar results. We evaluated the results of isolated polyethylene exchange for wear and/or osteolysis in 68 press-fit condylar TKAs from four centers. At a minimum of 24 months after polyethylene exchange surgery (average, 44 months; range, 24-83 months), there were 11 failures (16.2%). Failures included aseptic loosening in 10 knees and infection in one. With the relatively small cohort size we were unable to identify factors that predicted which knees were more likely to fail: we observed no correlation between failure and patient demographics, component design, or use of cement versus bone graft augmentation. Radiographic review demonstrated no progression of osteolytic lesions in 97% of knees in the study. While the short-term followup limits the conclusions, we believe the 84% success rate with modular polyethylene exchange for wear and osteolysis and the lack of progression of osteolytic lesions in the majority of the knees are encouraging. Full revision of well-fixed total knee components can lead to substantial bone loss, particularly in the face of osteolysis and we therefore consider modular polyethylene exchange in press-fit condylar knees a reasonable option for wear and osteolysis. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence

Importance of a balanced-gap technique in rotating-platform knees.

Rotating-platform knees are constructed of highly conforming polyethylene to reduce contact pressures that potentially cause wear. The mobile nature of the rotating platform can lead to bearing spin-out. The purpose of this study was to determine the prevalence of spin-out in a single series. A total of 426 knees in 393 patients were included in the study. All knees were implanted using a balanced-gap technique. The average follow up was 3.2 years. There were no cases of bearing spin-out. The author concludes that the balanced-gap technique reliably prevents spin-out in mobile-bearing total knee implantation. This implantation technique provides the potential wear benefits of the rotating platform design with a nominal bearing spin-out rate.

Total hip arthroplasty in patients with dwarfism.

BACKGROUND: Patients with short stature and osseous deformities resulting from osteochondrodysplasia frequently have premature development of advanced degenerative disease of the hip and thus may require total hip arthroplasty. The outcome of total hip arthroplasty in this group of young patients is unknown. In this study, we evaluated the long-term clinical and radiographic outcomes of total hip arthroplasty in patients with osteochondrodysplasia. METHODS: Between 1971 and 1997, sixty-two total hip arthroplasties were performed at our institution in thirty-seven patients with severe osteoarthritis secondary to osteochondrodysplasia. There were seventeen female patients and twenty male patients. Their average height was 142 cm, and their average age at the time of the index arthroplasty was thirty-seven years. The patients were followed clinically with use of the Harris hip score for a mean of 12.8 years, and they were followed radiographically for a mean of 11.5 years. RESULTS: The mean Harris hip score improved significantly (p < 0.0001), from 57 points preoperatively to 87 points at the time of the latest follow-up. Of the sixty hips available for follow-up, eighteen (30%) had required revision arthroplasty: fourteen required it because of aseptic loosening of one or both components; two, because of deep infection; one, because of periprosthetic fracture; and one, because of extensive osteolysis. There were two additional periprosthetic femoral fractures, which were treated with open reduction and internal fixation with retention of the components. The majority of patients had other functionally limiting conditions, such as spinal deformities, in addition to the degenerative arthritis. CONCLUSIONS: There was a high prevalence of complications, periprosthetic fractures, and mechanical failure in these patients with osteochondrodysplasia who underwent total hip arthroplasty. Young age, severe deformity, and multiple joint involvement may in part explain these findings. Nonetheless, total hip arthroplasty proved to be reliable for alleviating pain and improving function in patients with advanced symptomatic arthritis of the hip secondary to osteochondrodysplasia.