A modified Delphi consensus statement on patellar instability: part I.

Aims: The aim of this study was to establish consensus statements on the diagnosis, nonoperative management, and indications, if any, for medial patellofemoral complex (MPFC) repair in patients with patellar instability, using the modified Delphi approach. Methods: A total of 60 surgeons from 11 countries were invited to develop consensus statements based on their expertise in this area. They were assigned to one of seven working groups defined by subtopics of interest within patellar instability. Consensus was defined as achieving between 80% and 89% agreement, strong consensus was defined as between 90% and 99% agreement, and 100% agreement was considered to be unanimous. Results: Of 27 questions and statements on patellar instability, three achieved unanimous consensus, 14 achieved strong consensus, five achieved consensus, and five did not achieve consensus. Conclusion: The statements that reached unanimous consensus were that an assessment of physeal status is critical for paediatric patients with patellar instability. There was also unanimous consensus on early mobilization and resistance training following nonoperative management once there is no apprehension. The statements that did not achieve consensus were on the importance of immobilization of the knee, the use of orthobiologics in nonoperative management, the indications for MPFC repair, and whether a vastus medialis oblique advancement should be performed.

A modified Delphi consensus statement on patellar instability: part II.

Aims: The aim of this study was to establish consensus statements on medial patellofemoral ligament (MPFL) reconstruction, anteromedialization tibial tubercle osteotomy, trochleoplasty, and rehabilitation and return to sporting activity in patients with patellar instability, using the modified Delphi process. Methods: This was the second part of a study dealing with these aspects of management in these patients. As in part I, a total of 60 surgeons from 11 countries contributed to the development of consensus statements based on their expertise in this area. They were assigned to one of seven working groups defined by subtopics of interest. Consensus was defined as achieving between 80% and 89% agreement, strong consensus was defined as between 90% and 99% agreement, and 100% agreement was considered unanimous. Results: Of 41 questions and statements on patellar instability, none achieved unanimous consensus, 19 achieved strong consensus, 15 achieved consensus, and seven did not achieve consensus. Conclusion: Most statements reached some degree of consensus, without any achieving unanimous consensus. There was no consensus on the use of anchors in MPFL reconstruction, and the order of fixation of the graft (patella first versus femur first). There was also no consensus on the indications for trochleoplasty or its effect on the viability of the cartilage after elevation of the osteochondral flap. There was also no consensus on postoperative immobilization or weightbearing, or whether paediatric patients should avoid an early return to sport.

Effect of Concomitant Meniscal Tear on Strength and Functional Performance in Young Athletes 6 Months After Anterior Cruciate Ligament Reconstruction With Hamstring Autograft.

BACKGROUND: The effect of concomitant meniscal tears, and their associated treatment, on strength and functional recovery after anterior cruciate ligament reconstruction (ACLR) has not been adequately investigated in young populations. HYPOTHESIS: Concomitant meniscal tears, treated with or without repair, would not adversely affect strength, balance, or functional hop test performance at 6 months postoperatively. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The authors retrospectively analyzed return-to-sports (RTS) assessments prospectively collected 6 months after ACLR with hamstring autograft in 165 patients ≤25 years of age. Descriptive, surgical, and RTS testing data were analyzed, and subgroups were compared using analysis of covariance models designed to assess the effects of sex, meniscal tear, and meniscal repair on RTS performance. RESULTS: Included were 115 female (70%) and 50 male (30%) patients with a mean age of 16.4 years (range, 12.3-25 years). Of these patients, 58% had concomitant meniscal tears (59% lateral, 27% medial, 14% lateral + medial), comprising 53% of the female and 70% of the male patients. The authors treated 61% of the tears with repair, with range of motion (ROM) and weightbearing limitations imposed within the first 6 weeks postoperatively, whereas 39% were treated with partial meniscectomy, rasping, or trephination (no ROM or weightbearing restrictions). The mean deficit in hamstring strength at 6 months postoperatively was significantly greater in the meniscal tear group than in those without a tear (32.3% vs 24.6%; P = .028). The meniscal repair group had greater hamstring strength deficits than the group with meniscectomy, rasping or trephination (34.3% vs 26.2%; P = .023). Performance on dynamic balance and functional hop tests was similar among all meniscus subgroups. There were no sex-based effects on any subgroup comparisons. CONCLUSION: At 6 months postoperatively, both young male and young female patients who underwent ACLR with hamstring autograft demonstrated significant hamstring strength deficits compared with their nonoperative leg. The presence of a meniscal tear and subsequent repair, or its related rehabilitation restrictions, appears to have adverse effects on the postoperative recovery of hamstring strength.

The Biology of Sex and Sport.

Sex and gender are not the same. Sex is defined by the human genotype and pertains to biologic differences between males and females. Gender is a fluid concept molded by self-perception, social constructs, and culturally laden attitudes and expectations of men and women. In general, males have longer limb levers, stronger bones, greater muscle mass and strength, and greater aerobic capacity. Females exhibit less muscle fatigability and faster recovery during endurance exercise. Physiologic sex-based differences have led to an average performance gap of 10% that has remained stable since the 1980s. The performance disparity is lowest for swimming and highest for track and field events. The International Olympic Committee currently mandates that female athletes with differences of sex development, or intersex traits, and transgender female athletes must limit their blood testosterone to <10 nmol/L for 12 months to be eligible for competition in the female classification.

Kinematic sequence patterns in the overhead baseball pitch.

Conceptually, an efficient baseball pitch demonstrates a proximal-to-distal transfer of segmental angular velocity. Such a timing pattern (or kinematic sequence) reduces stress on musculoskeletal structures of the throwing arm and maximises ball velocity. We evaluated the variability of kinematic sequences in 208 baseball pitches. 3D biomechanical pitch analyses were performed on 8-10 fastball pitches from 22 baseball pitchers (5 high school, 11 collegiate and 6 professional). The kinematic sequence patterns - time of peak angular velocity of five body segments: pelvis, trunk, arm, forearm and hand - were measured. None of the pitches analysed demonstrated an entirely proximal-to-distal kinematic sequence. Fourteen different kinematic sequence patterns were demonstrated, with the most prevalent sequence being pelvis â†’ trunk â†’ arm â†’ hand â†’ forearm. Fewer than 10% of the pitchers performed only one kinematic sequence pattern across the sampled pitches. The variability of the kinematic sequence was similar in high-school pitchers and professionals. Previous studies report that deviation from the proximal-to-distal kinematic sequence is associated with increased injury risk. As a method of evaluating the efficient transfer of energy to the hand, the kinematic sequence may provide insight to injury risk in the future. The ideal kinematic sequence and ideal variability of the sequence when throwing have yet to be determined.

The Meniscal Grammar Signs: Comma and Apostrophe Signs for Characterization of a Displaced Fragment in the Meniscal Recess.

Vertical flap tears, or parrot beak flap tears, are oblique tears of the meniscus thought to originate as a central radial tear and propagate longitudinally towards the periphery, generating a partially detached unstable fragment that can subsequently displace into the meniscal recess. Although magnetic resonance imaging (MRI) is frequently used to diagnose and characterize meniscus pathology, imaging findings for displaced flap tears are not well described in the literature. The recently published meniscal comma sign describes inferior displacement of a meniscus flap tear into the meniscotibial recess that, when seen on MRI, resembles a comma. In the present article, we define the meniscal apostrophe sign, characterized by superior displacement of a meniscus flap tear into the meniscofemoral recess found on MRI. Displaced fragments in the meniscal recess are crucial to identify, as they often result in significant pain and mechanical symptoms related to tenting of the deep medial collateral ligament, which responds poorly to nonoperative treatment. Misdiagnosis of these unstable flap tears as degenerative meniscus extrusion or isolated progression of osteoarthritis can lead to a delay in treatment.