Impaired Modulation of Motor and Functional Performance in Patients after Total Knee Arthroplasty: A Prospective Observational Study.

Submaximal levels of effort are required for the performance of the most common daily tasks. Inaccuracy in modulating motor outputs during submaximal tasks has been reported as indicator of safety during daily activities in subjects with lower limb musculoskeletal disorders. The study is aimed at investigating performance modulation ability during motor and functional tasks in patients after total knee arthroplasty (TKA). Sixteen patients with end-stage osteoarthritis undergoing TKA and twenty age-matched healthy participants performed isokinetic knee extension, sit-to-stand, and walking tasks at three levels of self-estimated effort (100%, 50%, and 25%) the day before (T0) and 4 days after surgery (T1). Maximum performance in terms of peak torque (PT-knee extension), overshoot (OS-sit-to-stand), and walking speed was evaluated. Subsequently, relative error (RE) between target and observed performance was computed for the submaximal tasks (RE50% and RE25%). Our results showed a decline of maximum performance after surgery, which resulted lower in patients compared to healthy subjects. RE50% and RE25% for knee extension (involved limb) (p < 0.001) and RE25% for sit-to-stand (p < 0.001) increased from pre- to postsurgery. At T0, knee extension RE25% and walking RE50% and RE25% were higher in patients. At T1, RE50% and RE25% were higher in patients for knee extension (involved limb), sit-to-stand, and walking. In conclusion, the ability to modulate motor and functional performance decreased after TKA and resulted impaired when compared to healthy age-matched subjects. Based on relationship between ability to modulate motor outputs and risk of falling, the role of modulation ability as indicator of readiness for discharge and safe return to daily activities deserves further investigations in patients in early phase after TKA.

Conservative management of isolated medial subtalar joint dislocations in volleyball players: a report of three cases and literature review.

Isolated subtalar dislocations (SDs) are rare injuries, representing only 1% of all foot traumas. In the current literature, only a few reports have described this acute injury as a consequence of low-middle-energy trauma during sports activities and none in professional or recreational volleyball players. Further, to the best of our knowledge, no validated standard rehabilitation programs have been described for SDs as most of them are usually treated like an ankle sprain. This report describes 3 cases of isolated, closed medial SD, which occurred during non-professional volleyball activities. All cases were successfully treated by the same conservative method: standard radiographs for diagnosis, closed reduction, subsequent CT scan to exclude associated lesions, 4-week immobilization in a below-knee cast and an early physiokinesis therapy program. Further, a review of the recent literature concerning SD was performed. The standard method applied allowed our patients to return to full sports activity at 3 months from trauma, reaching a medium AOFAS score of 96.6 at minimum follow-up of 48 months. The treated cases and the review of the literature suggest that a conservative method and early mobilization should be the first-choice treatment for closed SD, even in volleyball players. Despite the absence of a sport-specific rehabilitation program for these injuries, early physiokinesis therapy, after no more than 4-week immobilization period, allowed the improvement of our patients' hindfoot stability and their fast return to full sports activities, without any recurrence at minimum follow-up of 2 years.

Acetabular spacers in 2-stage hip revision: is it worth it? A single-centre retrospective study.

PURPOSE: The aim of this work is to evaluate an acetabular antibiotic loaded bone cement spacer in 2-stage revision surgery as a potential approach able to reduce complications during the inter-stage period (i.e. dislocation, acetabular wear), as well as simplify 2-stage hip revision surgery and improve hip biomechanics. METHODS: We performed a retrospective comparative study and evaluated clinical, radiological and surgical data of 71 patients affected by periprosthetic hip infection who were treated with 2-stage exchange. 31 patients were treated using an acetabular spacer in addition to the femoral (group A) while 40 underwent a standard revision surgery (femoral spacer only, group B). RESULTS: Mean time of surgery for the first stage was 148 ± 59 minutes and 142 ± 45 minutes for group A and B respectively; we noted a statistically significant reduction (26 min, p = 0.015) in the same parameter for the second stage (83 ± 35 minutes for group A and 109 ± 36 minutes for group B). We observed the following interstage complications: 5 femoral spacer dislocations (1 for group A and 4 for group B); 1 spacer fracture (group B), 1 spacer fracture (group A), 2 periprosthetic fractures (group B) and 2 patients with acetabular spacer instability (group B). Additionally, we observed a significant improvement in leg length restoration for group A (p = 0.03). CONCLUSIONS: Our data show that the acetabular spacer technique is able to reduce the interstage complication rate and allow improved hip biomechanics restoration.