Project description:Development of Pectoralis major has been investigated through gene expression analysis in comparing animals receiving a restricted diet in P and Ca (NC), a normal diet with sufficient level of P and Ca (PC), and a restricted diet supplemented with phytase (Phy1000). We used microarrays (ChiGene-1_0-st) to evaluate gene expression underlying pathways affectd by the diet and/or the phytase supplementation and to identify classes of differentially expressed genes.
Project description:Pectoralis major (PM) ruptures are uncommon injuries, although they are becoming more frequent. We report a case of a PM rupture in a young male who presented with axillar pain and absence of the anterior axillary fold after he perceived a snap while lifting 200?kg in the bench press. Diagnosis of PM rupture was suspected clinically and confirmed with imaging studies. The patient was treated surgically, reinserting the tendon to the humerus with suture anchors. One-year follow-up showed excellent results. The patient was recording his training on video, so we can observe in detail the most common mechanism of injury of PM rupture.
Project description:Pectoralis major tendon ruptures can lead to significant functional deficits that affect high-level athletic and labor-intensive activities. In active populations operative repair of the ruptured pectoralis major tendon has shown significant advantages over nonoperative treatment. We describe a novel surgical technique for pectoralis major repair with tension button fixation. This study included 12 recreational athletes and 2 professional athletes. The initial results were measured subjectively after a minimum of 6 months by the Single Assessment Numeric Evaluation score, the American Shoulder and Elbow Surgeons score, and the ability to return to the patient's sport at a preinjury level. Objectively, strength was measured with resisted horizontal adduction of the arm for both repaired and contralateral sides. Of the 12 recreational patients, 8 returned to their sport at preinjury levels, and the 2 professional athletes returned to their sport at full capacity in the National Football League. The mean Single Assessment Numeric Evaluation score was 87, and the mean American Shoulder and Elbow Surgeons scores were 99 for both the operative and contralateral sides. Isokinetic strength testing showed no significant differences between the operative and nonoperative sides. Patients with pectoralis major tendons repaired with the proposed tensioned cortical button technique had excellent results. This new technique provides a reliable method of repair in an efficient and safe manner.
Project description:Over the past few decades, there has been increased awareness of pectoralis major muscle injuries necessitating further evaluation of management options and, in particular, surgical repair. Injury typically occurs when an eccentric load is applied to the muscle, such as with bench pressing, and failure usually occurs through the tendon. Although nonoperative management is sometimes appropriate, given the injury's propensity for young, active male patients, surgical intervention is often warranted. Because the injury typically occurs at the muscle-tendon interface, surgery focuses on repair of the avulsed tendon into its anatomic attachment site. We describe the use of a unicortical suture button to repair the ruptured tendon. This technique achieves the goals of strong fixation and anatomic repair of the tendon back into its native footprint.
Project description:BackgroundThe pectoralis major (PM) is made up of multilaminar muscle segments that form a complex insertion on the proximal humerus; it is composed of an anterior and a posterior tendon layer. The tear patterns and patient characteristics of operatively treated PM ruptures in the general population remain poorly understood.PurposeTo comprehensively report the demographic characteristics of patients who are clinically diagnosed with structurally significant PM ruptures and to describe PM tear patterns identified during surgery.Study designCase series; Level of evidence, 4.MethodsA retrospective analysis of surgically treated PM tears was performed for a single-surgeon case series between January 1, 2003, and November 1, 2017. Patient demographic characteristics, classification of tear pattern, and treatment (repair/reconstruction) were recorded.ResultsA total of 104 surgical cases of PM tendon rupture were identified; 100 patients underwent primary repair and 4 underwent dermal allograft reconstruction. All patients were male, with a mean age of 36.5 ± 9.2 years. Chronic tears (>6 weeks old) accounted for 63.6% of surgical cases, and 96% (n = 100) of tears occurred at or between the musculotendinous junction and tendinous insertion. A partial-thickness, complete-width tear of the posterior tendon layer at this same location was the most common tear pattern identified.ConclusionPM ruptures occurred almost exclusively at or between the musculotendinous junction and tendinous insertion, with predominant involvement of the posterior tendon layer. Chronic tears can be safely treated with primary repair in the vast majority of cases.
Project description:Scapular winging can be a significant source of chronic pain, weakness, and disability of the shoulder. Isolated serratus anterior palsy from long thoracic nerve injury, which is the most common cause of this condition, produces prominent winging and medial malpositioning of the inferior angle of the scapula. In the case of persistent symptoms despite conservative care, treatment options primarily include scapulothoracic fusion and pectoralis major transfer. Outcomes of scapulothoracic fusion are notable for a high complication rate and limited functional improvements. We describe our technique of indirect, split pectoralis major transfer to the inferolateral scapula with allograft tissue augmentation for the surgical treatment of chronic medial winging. This procedure provides dynamic stabilization of the scapula with secure and tension-free tendon transfer. Advantages over alternative treatments include a relatively low complication rate, acceptable cosmesis, and better range of motion. The rationale and technical aspects of this procedure are discussed. Additional clinical studies are warranted to compare outcomes for the direct and indirect split transfer methods.
Project description:Although injuries of the pectoralis major muscle are generally uncommon, ruptures of the pectoralis major are occasionally seen in younger, more active patients who participate in weightlifting activities. These injuries usually occur during maximal contraction of the muscle, while in extension and external rotation. In the case of a rupture, operative treatment is advocated especially in young, active patients regardless of the chronicity of the injury. Various surgical techniques for reattachment of the avulsed tendon have been described, but bone tunnel and suture anchor repair techniques are most widely used. In this Technical Note, we present our preferred technique for acute pectoralis major rupture repair involving use of cortical buttons for tendon stump-to-bone fixation.
Project description:Pectoralis major tendon rupture is a relatively rare injury, resulting from violent, eccentric contraction of the muscle. Over 50% of these injuries occur in athletes, classically in weight-lifters during the 'bench press' manoeuvre. We present 13 cases of distal rupture of the pectoralis major muscle in athletes. All patients underwent open surgical repair. Magnetic resonance imaging was used to confirm the diagnosis in all patients. The results were analysed using (1) the visual analogue pain score, (2) functional shoulder evaluation and (3) isokinetic strength measurements. At the final follow-up of 23.6 months (14-34 months), the results were excellent in six patients, good in six and one had a poor result. Eleven patients were able to return to their pre-injury level of sports. The mean time for a return to sports was 8.5 months. The intraoperative findings correlated perfectly with the reported MRI scans in 11 patients and with minor differences in 2 patients. We wish to emphasise the importance of accurate clinical diagnosis, appropriate investigations, early surgical repair and an accelerated rehabilitation protocol for the distal rupture of the pectoralis major muscle as this allows complete functional recovery and restoration of full strength of the muscle, which is essential for the active athlete.
Project description:A powerlifting athlete ruptured his left tendon of the pectoralis major muscle while attempting to lift 160 kg in a Brazilian bench press championship. The injury seemed to occur in the concentric phase of exercise; however, the more common mechanism of rupture is during the eccentric phase. The tendon was reinserted to the humerus 3 weeks later with screws and washers. The athlete returned to competitive activities after 5 months. One year later he lifted 170 kg and won the national championship.
Project description:PurposeThe purpose of this study was to determine return-to-play (RTP), performance and career survivorship for National Football League (NFL) athletes sustaining pectoralis major (PM) injuries with comparison among grades of injury and between nonoperative and operative management.MethodsPublicly available data from the 1998-2020 NFL seasons were reviewed to identify athletes with PM injuries. Athlete characteristics were collected 1 season before and 2 seasons after injury. Percent of total games played in a season, player efficiency rating (PER), and Pro Football Focus (PFF) grades were compared for the preinjury season and 2 postinjury seasons. Kaplan-Meier survivorship plots were computed for RTP and postinjury career length, whereas a log-rank test was used to compare survivorship differences.ResultsIn total, 258 PM injuries were reported at a mean age of 27.1 ± 3.3 years. A total of 126 surgical repairs occurred in 48.8% (n = 126) of injuries, with athletes undergoing repair possessing a lower RTP rate and longer time to RTP compared to athletes treated conservatively (P < .001). Survival analysis revealed shorter career length for athletes sustaining PM tears compared to strains (P < .001), although no difference in career length was appreciated on the basis of injury management (P = .980). Defensive linemen and wide receivers had lower PER during their second postinjury seasons (P = .019 and .030, respectively), whereas defensive linemen had lower PFF grades during their second post-injury seasons (P = .044).ConclusionNFL athletes requiring PM repair may experience a lower likelihood of RTP, and longer RTP timing, likely because of higher-grade injuries. Defensive linemen and wide receivers experiencing PM injuries are at risk for diminished performance post-injury. Career length does not appear to be affected based on injury management.Level of evidenceLevel III, cohort study.