Hyperbaric oxygen therapy enhances graft healing and mechanical properties after anterior cruciate ligament reconstruction: An experimental study in rabbits.

Hyperbaric oxygen therapy (HBOT) has proven successful in wound healing. However, its potential effects on anterior cruciate ligament (ACL) injuries remain uncertain. This study aimed to investigate the impact of HBOT on graft healing following ACL reconstruction in rabbits. Male New Zealand rabbits underwent ACL reconstruction and were randomly divided into two groups: the HBOT group and the ambient air group. The HBOT group received 100% oxygen at 2.5 atmospheres absolute for 2 h daily for 5 consecutive days, starting from the first day after surgery. The ambient air group was maintained in normal room air throughout the entire period. After 12 weeks following the surgery, animals were euthanized, and their knees were harvested for analysis. The HBOT group demonstrated superior graft maturation and integration in comparison to the ambient air group, as evidenced by lower graft signal intensity on magnetic resonance imaging, decreased femoral and tibial tunnel size, and higher bone mineral density values on high-resolution peripheral quantitative computed tomography scans. Additionally, biomechanical testing indicated that the HBOT group had greater load to failure and stiffness values than the ambient air group. In conclusion, the adjuvant use of HBOT improved ACL graft maturation and integration, reduced tunnel widening, and enhanced the biomechanical properties of the graft. These results may provide important insights into the potential clinical application of HBOT as a therapeutic intervention to enhance graft healing after ACL reconstruction, paving the way for further research in this area.

EXTENSOR MECHANISM TRANSPLANTATION AFTER KNEE PROSTHESIS: 70-MONTH FOLLOW-UP.

Objective: This article reports the range of motion, failure rate, and complications of patients with extensor mechanism injury after total knee arthroplasty (TKA) treated with extensor mechanism allograft with mid-term follow-up. Methods: Patients undergoing post-ATJ extensor mechanism transplantation from 2009 to 2018 were retrospectively evaluated. Demographics, the reason for transplantation, elapsed time from arthroplasty to transplantation, related surgical factors, immobilization time, range of motion, transplant failure, and complications were collected. The minimum follow-up was 24 months. Results: Twenty patients were evaluated. The mean follow-up was 70.8 +/- 33.6 months. The most common cause of extensor mechanism rupture was traumatic in 10 (50%) cases. Six patients underwent associated surgeries, one case of medial ligament complex reconstruction, and 5 cases of TKA revision. Eleven patients (55%) had transplant-related complications. The most common complication was an infection. Five cases presented transplant failure. Conclusion: Patients who underwent extensor mechanism allograft transplantation after total knee arthroplasty had a 25% failure rate with a mean follow-up of 6 years. Although there was no loss of flexion with the procedure and prolonged immobilization, the complication rate was not low. Level of evidence IV; case series .

Objetivo: O objetivo do estudo foi relatar amplitude de movimento, taxa de falha e complicações de pacientes com lesão do mecanismo extensor após artroplastia total do joelho (ATJ) tratados com aloenxerto do mecanismo extensor com acompanhamento no médio prazo. Métodos: Pacientes submetidos a transplante de mecanismo extensor pós-ATJ de 2009 a 2018 foram avaliados retrospectivamente. Foram avaliados dados demográficos, motivo do transplante, tempo decorrido da artroplastia ao transplante, fatores cirúrgicos relacionados, tempo de imobilização, arco de movimento, falha do transplante e complicações. O acompanhamento mínimo foi de 24 meses. Resultados: Vinte pacientes foram avaliados. O tempo médio de acompanhamento foi de 70,8 +/- 33,6 meses. A causa mais comum de ruptura do mecanismo extensor foi traumática em 10 (50%) casos. Seis pacientes foram submetidos a cirurgias associadas, um caso de reconstrução do complexo ligamentar medial e 5 casos de revisão de ATJ. Onze pacientes (55%) tiveram complicações relacionadas ao transplante. A complicação mais comum foi a infecção. Cinco casos apresentaram falha do transplante. Conclusão: Pacientes submetidos a transplante de aloenxerto de mecanismo extensor após artroplastia total de joelho apresentam taxa de falha de 25% com seguimento médio de 6 anos. Embora não tenha havido perda de flexão com o procedimento e com a imobilização prolongada, o índice de complicações não foi baixo. Nível de evidênvia IV; série de casos .

Pilot study of the effect of therapeutic photobiomodulation on postoperative pain in knee arthroplasty.

Nine participants undergoing primary TKA submitted to spinal anesthesia, sedation, ultrasound-guided obturator and Femoral nerve Block analgesia, and photobiomodulation Therapy (FBMT) were evaluated regarding postoperative pain and morphine consumption. FBMT sessions were performed in the Immediate Postoperative period (IPO) and after 24 hours. Participants received 16.7±15 mg of morphine up to the third postoperative day. At IPO, mean pain score was 4.8±3.2 and 5.6±3.5, at rest and on movement, respectively. Photo biomodulation therapy can be considered an option for mitigating pain for patients undergoing TKA.

Extensor mechanism transplantation after knee prosthesis: 70-month follow-up / Transplante de mecanismo extensor após prótese de joelho: seguimento 70 meses

ABSTRACT Objective: This article reports the range of motion, failure rate, and complications of patients with extensor mechanism injury after total knee arthroplasty (TKA) treated with extensor mechanism allograft with mid-term follow-up. Methods: Patients undergoing post-ATJ extensor mechanism transplantation from 2009 to 2018 were retrospectively evaluated. Demographics, the reason for transplantation, elapsed time from arthroplasty to transplantation, related surgical factors, immobilization time, range of motion, transplant failure, and complications were collected. The minimum follow-up was 24 months. Results: Twenty patients were evaluated. The mean follow-up was 70.8 +/- 33.6 months. The most common cause of extensor mechanism rupture was traumatic in 10 (50%) cases. Six patients underwent associated surgeries, one case of medial ligament complex reconstruction, and 5 cases of TKA revision. Eleven patients (55%) had transplant-related complications. The most common complication was an infection. Five cases presented transplant failure. Conclusion: Patients who underwent extensor mechanism allograft transplantation after total knee arthroplasty had a 25% failure rate with a mean follow-up of 6 years. Although there was no loss of flexion with the procedure and prolonged immobilization, the complication rate was not low. Level of evidence IV; case series .

RESUMO Objetivo: O objetivo do estudo foi relatar amplitude de movimento, taxa de falha e complicações de pacientes com lesão do mecanismo extensor após artroplastia total do joelho (ATJ) tratados com aloenxerto do mecanismo extensor com acompanhamento no médio prazo. Métodos: Pacientes submetidos a transplante de mecanismo extensor pós-ATJ de 2009 a 2018 foram avaliados retrospectivamente. Foram avaliados dados demográficos, motivo do transplante, tempo decorrido da artroplastia ao transplante, fatores cirúrgicos relacionados, tempo de imobilização, arco de movimento, falha do transplante e complicações. O acompanhamento mínimo foi de 24 meses. Resultados: Vinte pacientes foram avaliados. O tempo médio de acompanhamento foi de 70,8 +/- 33,6 meses. A causa mais comum de ruptura do mecanismo extensor foi traumática em 10 (50%) casos. Seis pacientes foram submetidos a cirurgias associadas, um caso de reconstrução do complexo ligamentar medial e 5 casos de revisão de ATJ. Onze pacientes (55%) tiveram complicações relacionadas ao transplante. A complicação mais comum foi a infecção. Cinco casos apresentaram falha do transplante. Conclusão: Pacientes submetidos a transplante de aloenxerto de mecanismo extensor após artroplastia total de joelho apresentam taxa de falha de 25% com seguimento médio de 6 anos. Embora não tenha havido perda de flexão com o procedimento e com a imobilização prolongada, o índice de complicações não foi baixo. Nível de evidênvia IV; série de casos .

The Impact of the Introduction of MELD on the Dynamics of the Liver Transplantation Waiting List in São Paulo, Brazil.

Until July 15, 2006, the time on the waiting list was the main criterion for allocating deceased donor livers in the state of São Paulo, Brazil. After this date, MELD has been the basis for the allocation of deceased donor livers for adult transplantation. Our aim was to compare the waitlist dynamics before MELD (1997-2005) and after MELD (2006-2012) in our state. A retrospective study was conducted including the data from all the liver transplant candidate waiting lists from July 1997 to December 2012. The data were related to the actual number of liver transplantations (Tr), the incidence of new patients on the list (I), and the number of patients who died while being on the waitlist (D) from 1997 to 2005 (the pre-MELD era) and from 2006 to 2012 (the post-MELD era). The number of transplantations from 1997 to 2005 and from 2006 to 2012 increased nonlinearly, with a clear trend to levelling to equilibrium at approximately 350 and 500 cases per year, respectively. The implementation of the MELD score resulted in a shorter waiting time until liver transplantation. Additionally, there was a significant effect on the waitlist dynamics in the first 4 years; however, the curves diverge from there, implying a null long-range effect on the waitlist by the MELD scores.