Purpose A peroneus longus tendon autograft is used in many orthopaedic procedures and it is biomechanically comparable to a hamstring tendon autograft. Despite its potential, there are few studies that have evaluated the use of the peroneus longus tendon in ACL reconstruction. The aim of this study was to compare the clinical outcome and donor site morbidity of ACL reconstruction with hamstring tendon autografts versus peroneus longus tendon autografts in patients with an isolated ACL injury. Methods Patients who underwent isolated single-bundle ACL reconstruction were allocated to two groups (hamstring and peroneus longus) and observed prospectively. Graft diameter was measured intraoperatively. Functional scores (IKDC, modiied Cincinnati and Lysholm scores) were recorded preoperatively and 1 year after surgery. Donor site morbidities were assessed with thigh circumference measurements and ankle scoring with the AOFAS and FADI. Results Fifty-two patients (hamstring n = 28, peroneus n = 24) met the inclusion criteria. The peroneus longus graft diameter (8.8 ± 0.7 mm) was signiicantly larger than the hamstring diameter (8.2 ± 0.8 mm) (p = 0.012). There were no signiicant diferences between the pre-and 1-year postoperative score between the hamstring and peroneus longus groups in the IKDC (n.s), modiied Cincinnati (n.s), and Lysholm (n.s). The mean for the AOFAS was 97.3 ± 4.2 and for the FADI 98 ± 3.4 in the peroneus longus group, with a signiicant decrease in thigh circumference in the hamstring group (p = 0.002). Conclusion Anterior cruciate ligament reconstruction with peroneus longus autografts produces a functional score (IKDC, modiied Cincinnati, Lysholm) comparable to that of hamstring autografts at a 1-year follow-up, with the advantages of larger graft diameter, less thigh hypotrophy and excellent ankle function based on AOFAS and FADI scores. Level of evidenceProspective cohort study, Level II. Abbreviations ACL Anterior cruciate ligament BPTB Bone-patellar tendon-bone MPFL Medial patellofemoral ligament IKDC International Knee Documentation Committee MCL Medial collateral ligament * Nicolaas C. Budhiparama

Background Anterior knee pain, which has a prevalence of 4% to 49% after TKA, may be a cause of patient dissatisfaction after TKA. To limit the occurrence of anterior knee pain, patellar denervation with electrocautery has been proposed. However, studies have disagreed as to the efficacy of this procedure. Questions/purposes We evaluated patients undergoing bilateral, simultaneous TKA procedures without patellar resurfacing to ask: (1) Does circumferential patellar cauterization decrease anterior knee pain (Kujala score) postoperatively compared with non-cauterization of the patella? (2) Does circumferential patellar cauterization result in better functional outcomes based on patient report (VAS score, Oxford knee score, and Knee Injury and Osteoarthritis Outcome Score) than non-cauterization of the patella? (3) Is there any difference in the complication rate (infection, patellar maltracking, fracture, venous thromboembolism, or reoperation rate) between cauterized patellae and non-cauterized patellae? Methods Seventy-eight patients (156 knees) were included in this prospective, quasi-randomized study, with each patient serving as his or her own control. Patellar cauterization was always performed on the right knee during simultaneous, bilateral TKA. Five patients (6%) were lost to follow-up before the 2-year minimum follow-up interval. A single surgeon performed all TKAs using the same type of implant, and osteophyte excision was performed in all patellae, which were left unresurfaced. Patellar cauterization was performed at 2 mm to 3 mm deep and approximately 5 mm circumferentially away from the patellar rim. The preoperative femorotibial angle and degree of osteoarthritis (according to the Kellgren-Lawrence grading system) were measured. Restoration of the patellofemoral joint was assessed using the anterior condylar ratio. Clinical outcomes, consisting of clinician-reported outcomes (ROM and Kujala score) and patient-reported outcomes (VAS pain score, Oxford knee score, and Knee Injury and Osteoarthritis Outcome Score), were evaluated preoperatively and at 1 month and 2 years postoperatively. Preoperatively, the radiologic severity of osteoarthritis, based on the Kellgren-Lawrence classification, was not different between the two groups, nor were the baseline pain and knee scores. The mean femorotibial angle of the two groups was also comparable: 189° ± 4.9° and 191° ± 6.3° preoperatively (p = 0.051) and 177° ± 2.9° and 178° ± 2.1° postoperatively (p = 0.751) for cauterized and non-cauterized knees, respectively. The preoperative (0.3 ± 0.06 versus 0.3 ± 0.07; p = 0.744) and postoperative (0.3 ± 0.06 versus 0.2 ± 0.07; p = 0.192) anterior condylar ratios were also not different between the cauterized and non-cauterized groups. Results At the 2-year follow-up interval, no difference was observed in the mean Kujala score (82 ± 2.9 and 83 ± 2.6 for cauterized and non-cauterized knees, respectively; mean difference 0.3; 95% confidence interval, -0.599 to 1.202; p = 0.509). The mean VAS pain score was 3 ± 0.9 in the cauterized knee and 3 ± 0.7 in the non-cauterized knee (p = 0.920). The mean ROM was 123° ± 10.8° in the cauterized knee and 123° ± 10.2° in the non-cauterized knee (p = 0.783). There was no difference between cauterized and non-cauterized patellae in the mean Knee Injury and Osteoarthritis Outcome Score for symptoms (86 ± 4.5 versus 86 ± 3.9; p = 0.884), pain (86 ± 3.8 versus 86 ± 3.6; p = 0.905), activities (83 ± 3.2 versus 83 ± 2.8; p = 0.967), sports (42 ± 11.3 versus 43 ± 11.4; p = 0.942), and quality of life (83 ± 4.9 versus 83 ± 4.7; p = 0.916), as well as in the Oxford knee score (40 ± 2.1 versus 41 ± 1.9; p = 0.771). Complications were uncommon and there were no differences between the groups (one deep venous thromboembolism in the cauterized group and two in the control group; odds ratio 0.49, 95% CI, 0.04-5.56; p = 0.57). Conclusions Patellar cauterization results in no difference in anterior knee pain, functional outcomes, and complication rates compared with non-cauterization of the patella in patients who undergo non-resurfaced, simultaneous, bilateral, primary TKA with a minimum of 2 years of follow-up. We do not recommend circumferential patellar cauterization in non-resurfaced patellae in patients who undergo TKA. Level of Evidence Level II, therapeutic study.

Background Accelerometer-based navigation is a handheld navigation tool that was introduced to offer a simpler technique compared with more-cumbersome computer-assisted surgery (CAS). Considering the increasing number of adopters, it seems important to evaluate the potential clinical benefits of this technology compared with conventional TKA. Questions/purposes In this systematic review, we asked: (1) Is accelerometer-based navigation more accurate than conventional TKA? (2) Does accelerometer-based navigation provide better functional outcome than conventional TKA? (3) Does accelerometer-based navigation increase surgical time or decrease the risk of complications or reoperations compared with conventional TKA? Methods This systematic review included all comparative prospective and retrospective studies published in the MEDLINE/PubMed and Cochrane libraries over the last 10 years. Inclusion criteria were all studies in English that compared accelerometer-based navigation with conventional TKA. Eleven studies met these criteria with 621 knees in accelerometer-based navigation group and 677 knees in conventional TKA group. Results related to alignment, objective and subjective functional scores, duration of surgery, complications and reoperations were extracted and compared between accelerometer-based-navigation and conventional TKA. Methodological quality was assessed using Methodological Index for Non-Randomized Studies (MINORS) tool (for nonrandomized control trials) and Cochrane Risk of Bias (for randomized control trials (RCTs). All studies with fair or better quality were included. Four RCTs and six nonrandomized studies comparing accelerometer-based navigation to conventional TKA were found. Results Inconsistent evidence on mechanical axis alignment was found, with five of nine studies slightly favoring the accelerometer-based navigation group, and the other four showing no differences between the groups. Only two of eight studies favored accelerometer-based navigation in terms of tibial component alignment in the coronal plane; the other six found no between-group differences. Similarly, mixed results were found regarding other metrics related to component alignment; a minority of studies favored accelerometer-based navigation by a small margin, and most studies found no between-group differences. Only three studies evaluated functional outcome and none of them showed a difference in range of motion or patient-reported outcomes. Most studies, six of seven, found no between-group differences concerning surgical time; one study demonstrated a slight increase in time with accelerometer-based navigation. There were no between-group differences in terms of the risk of complications, which generally were uncommon in both groups, and no reoperations or revisions were reported in either group. Conclusions We found conflicting evidence about whether accelerometer-based navigation reduces the number of coronal-plane outliers or improves alignment to a clinically important degree, and we found no evidence that it improves patient-reported outcomes or reduces the risk of complications or reoperations. Accelerometer-based navigation may increase surgical time. The overall quality of the evidence was low, which suggested that any observed benefits were overestimated. Given the absence of higher-quality evidence demonstrating compelling benefits of this accelerometer-based navigation technology, it should not be widely adopted. Level of Evidence Level III, therapeutic study.