Anders Stålman

Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells.

BackgroundTendinopathies are often empirically treated with oral/topical nonsteroidal anti-inflammatory medications and corticosteroid injections despite their unclear effects on tendon regeneration. Recent studies indicate that tendon progenitors exhibit stem cell-like properties, i.e., differentiation to osteoblasts, adipocytes, and chondrocytes, in addition to tenocytes. Our present study aims at understanding the effects of triamcinolone acetonide and diclofenac on tenocytic differentiation of mesenchymal stem cells.MethodsThe murine fibroblast C3H10T1/2 cell line was induced to tenocytic differentiation by growth differentiation factor-7. Cell proliferation and differentiation with the exposure of different concentrations of triamcinolone acetonide and diclofenac were measured by WST-1 assay and real-time polymerase chain reaction analysis, respectively.ResultsCell proliferation was decreased in a concentration-dependent manner when exposed to triamcinolone acetonide and diclofenac. In addition to tenocytic differentiation, adipocyte formation was observed, both at gene expression and microscopic level, when the cells were exposed to triamcinolone acetonide or high concentrations of diclofenac.ConclusionsOur results indicate that triamcinolone acetonide and diclofenac might alter mesenchymal stem cell differentiation in a nonfavorable way regarding tendon regeneration; therefore, these medications should be used with more caution clinically.

Medial Meniscus Resection Increases and Medial Meniscus Repair Preserves Anterior Knee Laxity: A Cohort Study of 4497 Patients With Primary Anterior Cruciate Ligament Reconstruction

Background: There are still controversies regarding the effects on knee laxity of additional meniscus resection or repair in the setting of anterior cruciate ligament reconstruction (ACLR). Hypothesis/Purpose: The purpose was to determine the effects on knee laxity of resection or repair of medial meniscus (MM) or lateral meniscus (LM) injuries in the ACLR knee. The hypothesis was that patients with an additional meniscus resection would have significantly increased postoperative knee laxity versus that of an isolated ACLR, whereas patients with meniscus repair would have laxity comparable to that of an isolated ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: The KT-1000 arthrometer, with an anterior tibial load of 134 N, was used to evaluate knee laxity preoperatively and at 6-month postoperative follow-up for a total of 4497 patients with primary hamstring tendon ACLR. Patients with isolated ACLR or ACLR with additional MM resection, MM repair, LM resection, LM repair, or MM plus LM resection were compared, with the isolated ACLR group as a control. Results: All patients showed a significant reduction of knee laxity preoperatively (3.6 ± 3.1 mm) to postoperatively (1.9 ± 2.2 mm) (P < 0.0001). Patients who had an ACLR with either an MM resection (2.2 ± 2.55 mm) or MM + LM resection (2.35 ± 2.30 mm) showed significant increased postoperative knee laxity versus isolated ACLR (1.74 mm ± 2.11 mm) (P < 0.05), whereas patients with MM repair (1.69 ± 2.37 mm) did not show significantly different knee laxity when compared with the control group (P > 0.05). LM resection or repair did not significantly affect knee laxity. Significantly more surgical failures, defined as side-to-side difference >5 mm, were found in the ACLR + MM resection group and the ACLR + MM + LM resection group. Conclusion: In ACLR, additional MM resection increased whereas MM repair preserved knee laxity in comparison with the ACLR knee with intact menisci. Neither LM resection or LM repair showed a significant effect on knee laxity. Surgeons should make every effort to repair the meniscus whenever possible to avoid the residual postoperative laxity present in the meniscus-deficient knee.

Meniscus repair with simultaneous ACL reconstruction demonstrated similar clinical outcomes as isolated ACL repair: a result not seen with meniscus resection

PurposeTo compare Knee Injury and Osteoarthritis Outcome Score (KOOS) and EuroQol-5D (EQ-5D) subscale scores at 2-year follow-up for patients with primary isolated ACL reconstruction with patients undergoing ACL reconstruction and simultaneous meniscal treatment in terms of either resection or repair in the Swedish National Knee Ligament Register (SNKLR).MethodsAll ACL reconstruction patients within the SNKLR at 2-year follow-up were reviewed. The KOOS and EQ-5D subscales were assessed in four distinct patient groups: isolated ACL reconstruction, ACL reconstruction + medial meniscus resection, ACL reconstruction + lateral meniscus resection, ACL reconstruction + medial meniscus repair, and ACL reconstruction + lateral meniscus repair. The primary analysis was conducted using linear regression with isolated ACL reconstruction designated as the reference group, and was adjusted for patient age, gender, and time from injury to surgery.ResultsThe included patients consisted of 10,001 (65.0%) individuals with an isolated ACL injury, 588 (3.8%) with ACL injury plus treated with medial meniscus repair, 2307 (15.0%) with ACL injury plus treated with medial meniscus resection, 323 (2.1%) with ACL injury plus treated with lateral meniscus repair, and 2173 (14.1%) with ACL injury plus treated with lateral meniscus resection. Meniscus resection demonstrated significantly worse results with respect to the KOOS Symptoms subscale for both the medial and lateral meniscus resection groups. Medial meniscus resection also demonstrated worse results for the KOOS quality of life (QoL) subscale, while lateral meniscus resection only approached significance. Outcomes were not different between the isolated ACL reconstruction group and the meniscus repair groups.ConclusionMeniscus resection in addition to ACL reconstruction resulted in worse clinical outcomes than isolated ACL reconstruction patients; a result not seen within the meniscus repair group. This suggests that, when possible, meniscus repair may provide greater clinical outcomes over resection when treating a reparable meniscal tear that presents along with an ACL tear. Clinicians should consider and implement these findings for the management of future meniscus tear patients within their clinical practice.Level of evidenceLevel III.

High or low return to sport rates following hip arthroscopy is a matter of definition

A 2018 meta-analysis reports an overall return to sports (RTS) rate of 91% and high patient satisfaction following hip arthroscopy for femoroacetabular impingement syndrome (‘arthroscopy’ in this paper).1 Even though three in four athletes were reported to return to pre-injury levels of sports, it remains unknown if they also reach their pre-injury level of performance. Currently, RTS is frequently defined as a binary outcome (ie, either as having returned to sport or not). This simple definition does not reflect the complexity of the dynamic RTS process; the more complex elements that constitute RTS were highlighted in the 2016 consensus statement on RTS.2 That statement recommends reporting RTS as a continuum from return to participation through return to sport and, finally, return to performance.2 This letter reports RTS rates following arthroscopy according to the continuum approach. In addition, patients’ satisfaction regarding RTS levels attained is presented. …