Surgical Outcomes and Analysis of Quality of Life Following Knee Arthroplasty in Very Elderly Patients.

In an aging population, the incidence of severe knee osteoarthritis in very elderly patients increases, leading to functional impairment and loss of independence. Knee replacement could be an effective treatment but is often denied due to fear of increased complication rate with advanced age. The objective of this study was to investigate complication rate, mortality, clinical outcome, and quality-adjusted life years (QALYs) of primary knee replacement in very elderly patients, defined as 83 years or older. Medical records of 85 cases, receiving a primary total (total knee arthroplasty [TKA]) or unicompartmental (unicompartmental knee arthroplasty [UKA]) knee replacement, aged 83 years or older at the time of surgery, were retrospectively reviewed for surgical and medical complications as well as survivorship. Functional outcome was obtained by Oxford Knee Score (OKS) and QALY. At a mean follow-up of 21 months (TKA) and 24 months (UKA), surgical and medical complication rates were 9.7 and 8.1% for TKA and 4.3 and 4.3% for UKA, respectively. One-year survival rate was 98.4% in TKA and 98.8% in UKA, the 5-year survival rate was 83.1 and 86.6%, respectively. OKS improved from 19 to 41 points in TKA and 23 to 40 points in UKA. Mean QALYs were 4.1 years for TKA and 3.9 years for UKA. TKA and UKA are safe and reliable surgical procedures in treating end-stage osteoarthritis in very elderly patients. Patients might benefit from improved pain, function, and quality of life. The mortality rate and overall complication rate were low, although slightly higher than reported in cohorts with younger patients. If the patient is suitable, UKA might be preferred over TKA, as the complication rate was significantly lower. Patients should not be excluded from knee replacement based on their age alone, but careful patient selection, peri- and postoperative optimization, and awareness for complications are quintessential for successful treatment.

Ankle Joint Pressure in Supination-External Rotation Injuries: A Biomechanical Study in an Unrestrained Cadaver Model.

BACKGROUND: Previous biomechanical studies simulating supination-external rotation (SER) IV injuries revealed different alterations in contact area and peak pressure. We investigated joint reaction forces and radiographic parameters in an unrestrained, more physiological setup. METHODS: Twelve lower leg specimens were destabilized stepwise by osteotomy of the fibula (SER II) and transection of the superficial (SER IVa) and the deep deltoid ligament (SER IVb) according to the Lauge-Hansen classification. Sensors in the ankle joint recorded tibio-talar pressure changes with axial loading at 700 N in neutral position, 10° of dorsiflexion, and 20° of plantarflexion. Radiographs were taken for each step. RESULTS: Three of 12 specimen collapsed during SER IVb. In the neutral position, the peak pressure and contact area changed insignificantly from 2.6 ± 0.5 mPa (baseline) to 3.0 ± 1.4 mPa (SER IVb) (P = .35) and from 810 ± 42 mm2 to 735 ± 27 mm2 (P = .08), respectively. The corresponding medial clear space (MCS) increased significantly from 2.5 ± 0.4 mm (baseline) to 3.9 ± 1.1 mm (SER IVb) (P = .028).The position of the ankle joint had a decisive effect on contact area (P = .00), center of force (P = .00) and MCS (P = .01). CONCLUSION: Simulated SER IVb injuries demonstrated radiological, but no biomechanical changes. This should be considered for surgical decision making based on MCS width on weightbearing radiographs. LEVELS OF EVIDENCE: Not applicable. Biomechanical study.