Arthroscopic supraglenoid origin-preserving biceps tenodesis: a reliable, simple, and cost-conscious technique.

BACKGROUND: The purpose of this study was to assess the midterm clinical and ultrasonographic outcomes of a new all arthroscopic supraglenoid origin-preserving tenodesis technique of the long head of the biceps (LHB) brachii tendon in the setting of small to medium-sized rotator cuff repairs. MATERIALS AND METHODS: Thirty patients (33 shoulders) meeting inclusion criteria were identified who underwent LHB tenodesis with this technique in the setting of small to medium-sized rotator cuff repair at a mean age at surgery of 65.6 years between 2015 and 2017. Rotator cuff tears were repaired using the Southern California Orthopedic Institute (SCOI) row technique. The biceps tenodesis was incorporated into the anterior anchor of the rotator cuff repair after bony groove preparation, including débridement and bone vent placement. Frayed edges of the biceps tendon were gently débrided, but the intra-articular glenoid attachment was left intact. Patients were assessed at follow-up by clinical and ultrasonographic examination, as well as a satisfaction questionnaire, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score and visual analog scale (VAS) score. RESULTS: Mean follow-up was 32.9 months for the 27 patients (30 shoulders), resulting in a 91% follow-up. Average ASES score was 94.4. Average patient-reported satisfaction with shoulder function was 9.4 of 10 and with biceps contour was 9.9 of 10. Average VAS score was 0.6 of 10, and 73% of patients reported a VAS score of 0. Ultrasonography demonstrated an intact biceps tendon in 27 of 28 shoulders and an intact supraspinatus tendon in all 28 shoulders. Mean range of motion was 170° in forward flexion, 169° in abduction, 49° in external rotation, and to thoracic vertebrae 12 in internal rotation. Mean muscle grading during Jobe test was 4.8 of 5. There were no intraoperative complications. No patients required revision surgery. CONCLUSIONS: In situ arthroscopic biceps tenodesis with maintenance of the glenoid attachment incorporated into rotator cuff repair yields a high rate of healing and consistently excellent functional and cosmetic outcomes as well as patient satisfaction while saving surgical time and cost.

Is it necessary to tie the medial row in rotator cuff repair double-row constructs when using suture tape?

PURPOSE: To evaluate the selected biomechanical differences of a double-row trans-osseous equivalent rotator cuff repair with a knotless versus knot-tying medial row using suture tape in regard to repair displacement, stiffness, and ultimate load to failure. METHODS: In 16 fresh-frozen human shoulders (8 matched pairs), double-row rotator cuff repairs were performed with medial-row mattress knots (MK) on one side, the other without (NK). Two DVRT (Differential Variable Reluctance Transducer) sensors were attached between the humerus and 3 mm above the repair site and were used to measure the displacement across the repair during cycling. The biomechanical parameters measured were repair displacement, stiffness, and ultimate load to failure. The supraspinatus was loaded in a similar fashion to previously described protocol using cyclic loading and load to failure testing.1. RESULTS: All data from paired specimens were compared using paired Student t tests. No statistically significant difference (SSD) in displacement across the repair over the 200 cycles of the test was noted between the two groups (MK = 0.591 ± 0.501 mm; NK = 0.439 ± 0.417 mm, p = 0.618). No SSD in stiffness was noted between the two groups (MK = 32.87 ± 6.31 N/mm; NK = 27.98 ± 9.69 N/mm, p = 0.120). No SSD in ultimate load to failure was noted between the two groups (MK = 501.2 ± 126.1 N; NK = 416.8 ± 120.0 N, p = 0.116). CONCLUSION: There was no statistically significant different between knotless versus knotted medial row double row rotator cuff repair constructs using suture tape in regard to displacement across the repair site, stiffness and ultimate load to failure. Despite previous evidence suggesting inferiority of knotless medial row technique using suture constructs, this evidence may support the biomechanical equivalency of knotless medial row technique using suture tape.

Acromioclavicular joint cyst formation.

Acromioclavicular joint (ACJ) cysts are an uncommon and unusual sequela associated with shoulder pathophysiology. The majority of literature on ACJ cysts consists of individual case reports with no definitive literature review currently available. In addition to a comprehensive literature review, four clinical cases are presented in this report. First described by Craig (1984), a total of 41 cases have been previously reported in the literature. Of these cases, five occurred with the rotator cuff musculature intact. The remaining 36 cases of ACJ cysts occurred in patients with a complete tear/avulsion of the rotator cuff. Previous attempts at compiling a complete record of all reported cases have combined several distinct conditions into a single category. This article presents two distinct etiologies for the pathogenesis of ACJ cyst formation. In the presence of an intact rotator cuff, a Type 1 cyst can form superficially and be limited to the ACJ. Following a massive or traumatic tear of the rotator cuff, mechanical instability of the humeral head can cause a deterioration of the inferior acromioclavicular capsule (cuff tear arthropathy) and an overproduction of synovial fluid. Overtime, a "geyser" of fluid can form between the glenohumeral and the ACJ, forming a Type 2 cyst. This differentiation and categorization is essential for appropriate classification and treatment.

Cell-permeable peptide antioxidants as a novel therapeutic approach in a mouse model of amyotrophic lateral sclerosis.

Reactive oxygen species (ROS) play a major role in the pathogenesis of neurodegenerative diseases. They are important contributors to necrotic and apoptotic cell death. A major proportion of cellular ROS is generated at the inner mitochondrial membrane by the respiratory chain. In the present study, we investigated a novel peptide antioxidant (SS-31) targeted to the inner mitochondrial membrane for its therapeutic effects both in vitro and in vivo in the G93A mouse model of amyotrophic lateral sclerosis (ALS). SS-31 protected against cell death induced by hydrogen peroxide in vitro in neuronal cells stably transfected with either wild-type or mutant Cu/Zn superoxide dismutase (SOD1). Daily intraperitoneal injections of SS-31 (5 mg/kg), starting at 30 days of age, led to a significant improvement in survival and motor performance. In comparison with vehicle-treated G93A mice, SS-31-treated mice showed a decreased cell loss and a decrease in immunostaining for markers of oxidative stress in the lumbar spinal cord. This further enhances the concept that pharmacological modification of oxidative stress is a therapeutic option for the treatment of ALS.

IGF-I prevents glutamate-induced motor neuron programmed cell death.

Insulin-like growth factor I (IGF-I) is currently in clinical trials for treatment of amyotrophic lateral sclerosis (ALS), but little is known about how it promotes the survival of motor neurons. In the current study, we examined IGF-I-mediated neuroprotection in an in vitro model of ALS utilizing enriched cultures of embryonic rat spinal cord motor neurons. IGF-I binds to the IGF-I receptor (IGF-IR) in motor neurons and activates MAPK and the downstream effector of phosphatidylinositol 3-kinase (PI-3K) signaling, Akt. IGF-I:IGF-IR signaling involves phosphorylation of IRS-1 and Shc, but not IRS-2. Glutamate, which is elevated in the cerebrospinal fluid of ALS patients, induced DNA fragmentation and caspase-3 cleavage in the spinal cord motor neurons. These effects of glutamate were blocked by co-treatment with IGF-I. However, a delay of IGF-I treatment for as little as 30 min eliminated its neuroprotective effect. Finally, alone, neither the MAPK pathway inhibitor PD98059 nor the PI-3K inhibitor LY294002 blocked the neuroprotective effect of IGF-I, but both inhibitors together were effective in this regard. These results suggest that the dose and timing of IGF-I administration are critical for producing a neuroprotective effect, and also suggest that both the MAPK and PI-3K/Akt pathways can promote the survival of motor neurons. We discuss our results in terms of novel strategies for ALS therapy.