Knotted Transosseous-Equivalent Technique for Rotator Cuff Repair Shows Superior Biomechanical Properties Compared With a Knotless Technique: A Systematic Review and Meta-analysis.

PURPOSE: To compare the biomechanical properties of the knotted versus knotless transosseous-equivalent (TOE) techniques for rotator cuff repair (RCR). METHODS: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using PubMed, Embase, and the Cochrane Library to identify studies that compared the biomechanical properties of knotted and knotless TOE RCR techniques. The search phrase used was as follows: (Double Row) AND (rotator cuff) AND (repair) AND (biomechanical). Evaluated properties included ultimate load to failure, cyclic displacement, stiffness, footprint characteristics, and failure mode. RESULTS: Eight studies met the inclusion criteria, including a total of 67 specimens in each group. Of 6 studies reporting on ultimate load to failure, 4 found tendons repaired with the knotted TOE technique to experience significantly higher ultimate load to failure compared with knotless TOE repairs (knotted range, 323.5-549.0 N; knotless range, 166.0-416.8 N; P < .05). Of 6 studies reporting on failure stiffness, 2 found knotted TOE repairs to have significantly higher failure stiffness compared with knotless TOE repairs (knotted range, 30.0-241.8 N/mm; knotless range, 28.0-182.5 N/mm; P < .05), whereas 1 study found significantly higher failure stiffness in knotless TOE repairs compared with knotted TOE repairs (P = .039). Cyclic gap formation favored the knotted TOE group in 2 of 3 studies (knotted range, 0.6-5.2 mm; knotless range, 0.4-9.1 mm; P < .05). The most common mode of failure in both groups was suture tendon tear. CONCLUSIONS: On the basis of the included cadaveric studies, rotator cuff tendons repaired via the knotted TOE technique display superior time-zero biomechanical properties, including greater ultimate load to failure, compared with rotator cuffs repaired via the knotless TOE technique. Suture tearing through the tendon remains a common failure method for both techniques. CLINICAL RELEVANCE: The results of this systematic review provide helpful insight into the biomechanical differences between 2 popular techniques for RCR. Although these results should be carefully considered by surgeons who are using either of these techniques in the operating room, they should not be mistaken for direct clinical applicability because cadaveric studies may not directly correlate to clinical outcomes.

Effects of Running on the Development of Knee Osteoarthritis: An Updated Systematic Review at Short-Term Follow-up.

Background: Some studies have suggested that running increases the risk of knee osteoarthritis (OA), while others believe it serves a protective function. Purpose: To perform an updated systematic review of the literature to determine the effects of running on the development of knee OA. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was performed by searching the PubMed, Cochrane Library, and Embase databases to identify studies evaluating the effect of cumulative running on the development of knee OA or chondral damage based on imaging and/or patient-reported outcomes (PROs). The search terms used were "knee AND osteoarthritis AND (run OR running OR runner)." Patients were evaluated based on plain radiographs, magnetic resonance imaging (MRI), and PROs (presence of knee pain, Health Assessment Questionnaire-Disability Index, and the Knee injury and Osteoarthritis Outcome Score). Results: Seventeen studies (6 level 2 studies, 9 level 3 studies, and 2 level 4 studies), with 7194 runners and 6947 nonrunners, met the inclusion criteria. The mean follow-up time was 55.8 months in the runner group and 99.7 months in the nonrunner group. The mean age was 56.2 years in the runner group and 61.6 years in the nonrunner group. The overall percentage of men was 58.5%. There was a significantly higher prevalence of knee pain in the nonrunner group (P < .0001). Although 1 study found a significantly higher prevalence of osteophytes in the tibiofemoral (TF) and patellofemoral (PF) joints within the runner group, multiple studies found no significant differences in the prevalence of radiographic knee OA (based on TF/PF joint-space narrowing or Kellgren-Lawrence grade) or cartilage thickness on MRI between runners and nonrunners (P > .05). One study found a significantly higher risk of knee OA progressing to total knee replacement among nonrunners (4.6% vs 2.6%; P = .014). Conclusion: In the short term, running is not associated with worsening PROs or radiological signs of knee OA and may be protective against generalized knee pain.