Study Design: Descriptive, prospective, longitudinal single-cohort study. Objective: To investigate the rate of force development to 30% (RFD₃₀), 50% (RFD₅₀), and 90% (RFD₉₀) of maximal voluntary isometric contraction (MVIC) as an adjunct outcome measure for determining readiness for return to sport following an anterior cruciate ligament (ACL) reconstruction. Background: One criterion of full recovery following an ACL reconstruction is the ability to achieve 85% or 90% of the maximal strength of the contralateral limb. However, the time required to develop muscular strength in many types of daily and sports activities is considerably shorter than that required to achieve maximal strength. Therefore, in addition to maximal strength, neuromuscular functions such as RFD should also be considered in the definition of recovery. Methods: Forty-five male professional soccer players who underwent an ACL reconstruction were recruited. Assessment with the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Tegner score, and KT1000 instrumented arthrometer was performed postinjury/prereconstruction and at 6 and 12 months after ACL reconstruction. MVIC, RFD₃₀, RFD₅₀, and RFD₉₀ testing was performed preinjury, as part of standard preseason assessment, and at 6 and 12 months post-ACL reconstruction. Results: The average MVIC value 6 months postreconstruction was 97% of the preinjury average value. In contrast, at 6 months, the RFD₃₀, RFD₅₀, and RFD₉₀ values were 80% (P = .04), 77% (P = .03), and 63% (P = .007), respectively, of the preinjury values. The mean RFD values for the reconstructed knee attained or exceeded 90% of the preinjury mean values only at the 12-month post-ACL reconstruction assessment (RFD₃₀, P = .86; RFD₅₀, P = .51; RFD₉₀, P = .56). Conclusion: Despite the near recovery of MVIC strength to preinjury levels, there were still significant deficits in RFD at 6 months post-ACL reconstruction. An RFD similar to the preinjury RFD was achieved at 12 months post-ACL reconstruction, following a rehabilitation program focusing on muscle power. These results suggest that, following an ACL reconstruction, RFD criteria may be a useful adjunct outcome measure for the decision to return athletes to sports. J Orthop Sports Phys Ther 2012;42(9):772–780, Epub 19 July 2012. doi:10.2519/jospt.2012.3780

Despite the advancement of diagnostic surgical techniques in anterior cruciate ligament (ACL) reconstruction and rehabilitation protocols following ACL injury, only half of the athletes return to sports at a competitive level. A major concern is neuromechanical dysfunction, which occurs with injuries persisting in operated and non-operated legs following ACL rehabilitation. One of the criteria for a safe return to sports participation is based on the maximal voluntary isometric contraction (MVIC) performed unilaterally and a comparison between the ‘healthy knee’ and the ‘operated knee’. The present study aimed to investigate MVIC in athletes following ACL rehabilitation during open kinetic chain exercise performed unilaterally and bilateral exercises. Twenty subjects participated in the present investigation: 10 male athletes of regional–national level (skiers, rugby, soccer, and volleyball players) who were previously operated on one knee and received a complete rehabilitation protocol (for 6–9 months) were included in the ACL group (age: 23.4 ± 2.11 years; stature: 182.0 ± 9.9 cm; body mass: 78.6 ± 9.9 kg; body mass index: 23.7 ± 1.9 kg/m²), and 10 healthy male athletes formed the control group (CG: age: 24.0 ± 3.4 years; stature: 180.3 ± 10.7 cm; body mass: 74.9 ± 13.5 kg; body mass index: 22.8 ± 2.7 kg/m²). MVICs synchronised with electromyographic (EMG) activity (recorded on the vastus lateralis, vastus medialis, and biceps femoris muscles) were performed during unilateral and bilateral exertions. The rate of force development (RFD) and co-activation index (CI) were also calculated. The differences in the MVIC and RFD between the two legs within each group were not significant (p > 0.05). Vastus lateralis EMG activity during MVIC and biceps femoris EMG activity during RFD were significantly higher in the operated leg than those in the non-operated leg when exertion was performed bilaterally (p < 0.05). The CI was higher in the operated leg than that in the non-operated leg when exertion was performed bilaterally (p < 0.05). Vice versa, vastus medialis EMG activity during RFD was significantly higher in the right leg than that in the left leg when exertion was performed bilaterally (p < 0.05) in the CG. MVICs performed bilaterally represent a reliability modality for highlighting neuromechanical asymmetries. This bilateral exercise should be included in the criteria for a safe return to sports following ACL reconstruction.

Introduction: Total knee arthroplasty is an effective operation. Post-surgery rehabilitation, based on early and intensive progressive exercise programs, plays a substantial role and telerehabilitation can be an effective safe option. This retrospective study aimed to compare traditional in-presence rehabilitation and telerehabilitation for total knee arthroplasty, based on our experience during the Italian COVID-19 lockdown. Materials and methods: We retrospectively analyzed 164 patients (94 females and 70 males) enrolled in 2020 within 2 weeks after total knee replacement to perform post-operative outpatient rehabilitation. The clinical results of 82 patients (mean age 66.8 ± 10.2 years) performing telerehabilitation with those obtained from a similar cohort of 82 patients (mean age 65.4 ± 11.8 years) performing traditional in-presence outpatient rehabilitation were compared. Clinical outcomes were examined by comparing the gait speed (Time Up and Go-TUG test), the range of motion, the pain intensity (VAS), the functional status (Oxford Knee Score—OKS and Knee injury and Osteoarthritis Outcome Score—KOOS) and the overall satisfaction (Self-administered patient satisfaction scale) 12 weeks after the beginning of the physiotherapeutic protocol. Results: Telerehabilitation was non-inferior to traditional in-presence rehabilitation in all of the investigated areas and no statistical difference in terms of effectiveness was detected at 12 weeks, as confirmed by the respective patient-reported outcome scores such as TUG test (reduced from 20 ± 2 s to 12 ± 1.5 s for the telerehab cohort and from 18 ± 1.5 s to 13.1 ± 2 s for the in-presence rehabilitation one), pain VAS, OKS (improved from 22 ± 1.3 to 36 ± 2.7 for the telerehab cohort and from 23 ± 2.1 to 35.1 ± 4.2 for the in-presence group), KOOS (improved from 46.2 ± 10.2 to 67.4 ± 3.8 for the telerehabilitation cohort and from 48.4 ± 8.4 to 68.3 ± 6.6 for the other group), and the Self-administered patient satisfaction scale (more than two-thirds of patients globally satisfied with the results of their surgery in both groups). Conclusion: The telerehabilitation program was effective after total knee replacement and yielded clinical outcomes that were not inferior to conventional outpatient protocols.

Background: High tibial osteotomy (HTO) provides reliable and good long-term results, if performed with correct indications, but different techniques and types of fixation have been described. The purpose of this study is to present a novel modified biplanar medial opening-wedge (MOW) HTO technique where the osteotomies are performed in a Z-shaped fashion, and to present the medium-term clinical and radiographic results. Materials and methods: We present a case series of 75 patients (80 knees) with mean age of 45.8 years, affected by isolated medial knee osteoarthritis and symptomatic varus knee malalignment, who underwent novel biplanar Z-shaped MOWHTO. Clinical and radiological outcomes were collected, retrospectively before surgery and at median follow-up of 7.2 years (95% CI 5.6–9.2 months) after surgery. Clinical results and satisfaction were assessed by visual analog scale (VAS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and Likert scale. Radiological assessment involved the evaluation of the medial proximal tibial angle (MPTA), tibial slope (TS), Caton–Deschamps index, and knee osteoarthritis grade according to Ahlbäck classification. Pre- and postoperative results were compared using the two-tailed t-test or Wilcoxon’s test of independent samples for paired data or nonparametric analog. P < 0.05 was considered significant. Results: At medium-term follow-up, Z-shaped MOWHTO showed a survival rate of 95 ± 1.7% with failure occurring in four knees due to symptom recurrence and osteoarthritis progression. No perioperative complications were observed (intraarticular fracture, delayed union or nonunion, and neurological injury). Mean bone healing time was 12 weeks. Clinical scores showed significant improvement at last follow-up and a good grade of satisfaction. MPTA increased significantly, while Caton–Deschamps index decreased significantly. No significant TS increase was found. Conclusions: Modified biplanar Z-shaped MOWHTO is a safe and reliable technique that offers satisfactory clinical and radiological medium-term outcomes with low knee arthroplasty conversion rate. The unique three-dimensional geometrical conformation potentially provides a favorable environment for bone healing, increased anteroposterior and rotational stability, and safer opening-wedge loading force application with low lateral hinge fracture risk. Level of evidence: Level IV, retrospective observational case series study. Trial registration The study protocol was approved by the Internal Review Board of our Institution (authorization number 54/2019, 20 November 2019).

Background: this study considers the analysis of postural sway by comparing the use of a fractal dimension outcome (DBOX) with the usual sway ellipse area (SEA), calculated by the least squares method. Both the response variables come from centre of pressure (COP) dynamics detected by means of a force platform. Methods: recent literature regarding postural stability assessment in subjects with muscularskeletal disorders, or neuromuscular diseases affecting their motor skills, has suggested, both for practical and theoretical reasons, the use of some fractal dimension as a good outcome measurement for overall postural status. A sample group of 24 male subjects was recruited. The postural stabilogram was recorded both with eyes open (EO) and eyes closed (EC) while standing upright. A matched-pair comparison of the sway ellipse area with the COP dynamics box counting dimension was performed. A ROC analysis of the outcome variables was performed. Then, a ROC comparison of the tests, using the area under the curve (AUC) index, was conducted. Results: the comparison of paired groups showed a statistically significant difference between EO and EC status, according to the sway ellipse area and the fractal dimension (p<0.05). The ROC analysis, describing the test performance in terms of AUC difference, was statistically significant (p<0.05). The comparison of the AUCs showed an overall superior performance of the DBOX with respect to SEA (p<0.05). Conclusions: this study showed a statistically significant better overall performance of DBOX with respect to SEA, suggesting possible improvements of clinical practice, as well as theoretical insights into the response patterns.