Anterior cruciate ligament repair versus reconstruction: A clinical, MRI and patient-reported outcome comparison.

BACKGROUND: There has been a resurgence in anterior cruciate ligament (ACL) repair for proximal tears using modern surgical techniques and technology. This study aims to compare ACL repair with reconstruction using MRI, clinician-measured and patient-reported outcome measures (PROMs). METHODS: A post-hoc analysis was performed on prospectively collected data from 20 consecutive primary ACL repairs by the senior author. This was compared with an age and sex-matched cohort of 20 ACL reconstructions by the same surgeon using PROMs, return-to-sport (RTS) testing, and MRI signal noise quotient (SNQ). RESULTS: Repairs demonstrated equivalent post-operative PROMs to reconstructions as measured by International Knee Documentation Committee subjective score (78.5 ± 17.1 vs. 83.7 ± 13.3, P = 0.333), Tegner Activity Scale (5.9 ± 1.8 vs. 6.1 ± 2.6, P = 0.646) and Lysholm score (89.8 ± 10.0 vs. 89.6 ± 10.4, P = 0.762). There was no difference in repairs and reconstructions passing quadriceps strength criteria (50% vs. 53%, P = 0.097). A greater proportion of repairs passed hamstrings strength criteria (86% vs. 60%, P = 0.023) and hamstrings-to-quadriceps ratio (71% vs. 20%, P = 0.003). There were no differences across hop and Y-balance testing. Repairs had earlier RTS assessment (8.2 ± 2.8 months vs. 10.6 ± 1.4 months, P = 0.020). On 12-month MRI, repairs demonstrated higher femoral (8.8 ± 5.7 vs. 4.6 ± 2.9, P = 0.009) and tibial SNQ (10.0 ± 5.7 vs. 4.3 ± 4.2, P = 0.001), with no mid-substance difference (12.3 ± 8.5 vs. 7.6 ± 5.2, P = 0.074). There were no graft failures. CONCLUSIONS: When patient selection is optimized for proximal tears, ACL repairs demonstrate equivalent PROMs and better objective outcomes to reconstructions at an earlier timepoint. Repair tissue quality on MRI shows higher signal at tibial and femoral attachments.

How does the use of quantified gap-balancing affect component positioning and limb alignment in robotic total knee arthroplasty using functional alignment philosophy? A comparison of two robotic platforms.

PURPOSE: This study aimed to compare the effect of an image-based (MAKO) system using a gap-balancing technique with an imageless (OMNIbot) robotic tool utilising a femur-first measured resection technique. METHODS: A retrospective cohort study was performed on patients undergoing primary TKA with a functional alignment philosophy performed by a single surgeon using either the MAKO or OMNIbot robotic systems. In all cases, the surgeon's goal was to create a balanced knee and correct sagittal deformity (eliminate any fixed flexion deformity). Intra-operative data and patient-reported outcomes (PROMS) were compared. RESULTS: A total of 207 MAKO TKA and 298 OMNIbot TKAs were analysed. MAKO TKA patients were younger (67 vs 69, p=0.002) than OMNIbot patients. There were no other demographic or pre-operative alignment differences. Regarding implant positioning, in MAKO TKAs the femoral component was more externally rotated in relation to the posterior condylar axis (2.3° vs 0.1°, p<0.001), had less valgus femoral cuts (1.6° vs 2.7° valgus, p<0.001) and more varus tibial cuts (2.4° vs 1.9° varus, p<0.001), and had more bone resected compared to OMNIbot TKAs. OMNIbot cases were more likely to require tibial re-cuts than MAKO (15% vs 2%, p<0.001). There were no differences in femur recut rates, soft tissue releases, or rate of achieving target coronal and sagittal leg alignment between robotic systems. A subgroup analysis of 100 MAKO and 100 OMNIbot propensity-matched TKAs with 12-month follow-up showed no significant difference in OKS (42 vs 43, p=0.7) or OKS PASS scores (83% vs 91%, p=0.1). MAKO TKAs reported significantly better symptoms according to their KOOS symptoms score than patients that had OMNIbot TKAs (87 vs 82, p=0.02) with a higher proportion of KOOS PASS rates, at a slightly longer follow-up time (20 months vs 14 months, p<0.001). There were no other differences in PROMS. CONCLUSION: A gap-balanced technique with an image-based robotic system (MAKO) results in different implant positioning and bone resection and reduces tibial recuts compared to a femur-first measured resection technique with an imageless robotic system (OMNIbot). Both systems achieve equal coronal and sagittal deformity correction and good patient outcomes at short-term follow-ups irrespective of these differences.

Anteroposterior tear size, age, hospital, and case number are important predictors of repair integrity: an analysis of 1962 consecutive arthroscopic single-row rotator cuff repairs.

BACKGROUND: Retear or nonhealing of a surgically repaired rotator cuff is common, but the determinants of retear are poorly understood. We aimed to determine the relationship between preoperative and intraoperative factors and retear rate following rotator cuff repair and to formulate a predictive model based on this relationship, including any interaction effects between tear size, patient age, and surgical experience in contributing to the retear rate. METHODS: We performed a post hoc analysis of prospectively collected data from 1962 consecutive patients who underwent a primary arthroscopic single-row rotator cuff repair performed by the senior author from 2007 through 2018 and postoperatively returned for 6-month follow-up ultrasonography. RESULTS: Multiple logistic regression analysis revealed anteroposterior tear length to be the most important independent predictor of retear (Wald statistic, 90; P < .001). Other independent predictors included case number (Wald statistic, 59; P < .001), patient age at surgery (Wald statistic, 30; P < .001), and type of hospital (public vs. private) (Wald statistic, 17; P < .001). The data indicated that following rotator cuff repair, there was a 4-fold increase in the retear rate as the anteroposterior tear size increased from 1 cm to 3 cm; a 8-fold decrease when comparing case number 1000 with case number 3000; a 2-fold increase as patient age increased from 50 years to 70 years; and a 3-fold increase when comparing surgery performed in a public hospital vs. a private hospital. The area under the receiver operating characteristic curve was 0.81 (95% confidence interval, 0.78-0.84), indicating that our equation could predict 81% of retears. CONCLUSIONS: Anteroposterior tear length was the most important independent predictor of retear or nonhealing. Other predictive factors included case number, patient age at surgery, and hospital type. The predictive effect of anteroposterior tear length, patient age, and case number in contributing to retear was additive. Our regression equation may be used to calculate patient rotator cuff retear risk at 6 months after repair.