The Effect of Total Knee Replacement on Dual-Task Gait Performance in Older Adults.

OBJECTIVE: Total knee replacement (TKR) is a common solution for patients with advanced knee osteoarthritis (OA). Still, fall rates remain relatively high after surgery. TKR may alter pain and knee function, balance control, and proprioception. However, given the role of complex (dual-task) walking in fall prediction for older adults, it is unknown how TKR alters the attentional demand of walking in older adults. The goal of this study was to examine the effect of TKR on dual-task walking among older adults. METHODS: Participants were evaluated 1 month before surgery and 4.5 months after surgery. Participants walked along an instrumented 7-meter path for 1 minute with and without a cognitive task (serial-3 subtraction). Pain and knee function, knee proprioception, dynamic balance, and balance confidence, as well as dual-task costs (DTC) were compared before and after the surgery and factors associated with change in gait DTCs were assessed. RESULTS: Thirty-eight participants completed the study (age 72.6 years, SD = 4.9; 11 men). A significant decrease in pain was found following TKR, with no change in balance, balance confidence, or proprioception. There were no differences in gait DTCs before and after the surgery. However, change in dynamic balance, specifically reactive postural control and dynamic gait, predicted changes in gait speed and stride time DTCs. CONCLUSION: The absence of an effect of TKR on gait DTCs can potentially underlie increased fall risk after TKR. Results from this study emphasize the significance of balance as a measure and focal point for rehabilitation after TKR. IMPACT: This study contributes to our understanding of the attentional cost of walking in people before and after TKR, as well as to factors associated with it. Results from this work can assist formulation of rehabilitation programs for people with knee OA.

Successful reconstruction of natural femoral anteversion using a short femoral stem in total hip arthroplasty surgery.

OBJECTIVE: Total hip arthroplasty (THA) involves postoperative risks, such as thigh pain, periprosthetic fractures, and stress yielding. Short, anatomical, metaphyseal-fitting, cementless femoral stems were developed to reduce these postoperative risks. This study aimed to examine the "MiniMAX" prosthesis, which is a new generation, short, anatomical femoral stem made by Medacta. METHODS: Patients underwent a low-dose computed tomography scan. Femoral anteversion was measured. We assessed the position and anteversion of the femoral component and compared them with the unoperated side. We also assessed the patients' satisfaction and functional levels at 6 months postsurgery using the Harris Hip Score (HHS) and the Oxford Hip Score (OHS). RESULTS: Nineteen individuals were recruited in this study. We found no significant difference in femoral anteversion between the operated hip and the native hip. Using the HHS and OHS questionnaires, we found clinical improvement in the 6-month postoperative scores compared with the preoperative scores. DISCUSSION: The new-generation, short, anatomical femoral stem made by Medacta is successful in reproducing natural femoral anteversion, while also improving patients' functioning and lifestyle. Future large-scale, prospective comparison trials are required to further investigate this topic.

Renal cell carcinoma in a child presented as bilateral femur neck fractures caused by severe vitamin D deficiency.

An Ethiopian girl 14 years and 11 months of age presented with bilateral transcervical hip fractures. Workup revealed severe vitamins D and C deficiencies with secondary hyperparathyroidism. Imaging studies showed bilateral radiolucent metaphyseal bands with multiple lytic lesions in long bones. A mass in the right flank was found to be renal cell carcinoma (RCC). Currently, 9 months postsurgery and supplemental therapy, the patient is fully ambulatory and free of pain. This first report of asymptomatic RCC in severely vitamin D deficient child highlights the relation of RCC to vitamin D deficiency and emphasizes the importance of careful evaluation of these children.

Avulsion of the triceps tendon during acceleration stress.

The authors present a rare case of triceps tendon avulsion associated with +5 G-force and muscle straining. Although failure of musculoskeletal system, mainly the cervical spine, secondary to high-G exposure has been reported, this is the first report they have found of a triceps tendon avulsion. Furthermore, unlike other traumatic triceps avulsions reported, the pilot involved had no known predisposing factors. Awareness of the possibility of such an injury must be maintained when a pilot of high performance aircraft presents with elbow pain.