Pre-operative quadriceps strength predicts IKDC2000 scores 6 months after anterior cruciate ligament reconstruction

Level of evidenceLevel II.BackgroundQuadriceps strength deficits are ubiquitous after anterior cruciate ligament (ACL) injury. Deficits prior to surgery can influence knee function post-operatively. Inhibition contributes to quadriceps strength deficits after an ACL injury. Body mass index, meniscal injury, and sex influence functional outcomes after ACL reconstruction. The purpose of this study is to examine the relationship of pre-operative quadriceps strength and post-operative knee function and to investigate how other pre-operative factors may influence this relationship.MethodsAfter an ACL injury, subjects received pre-operative rehabilitation and performed quadriceps strength testing. Subjects underwent reconstruction and post-operative rehabilitation. Six months after ACL reconstruction, subjects completed the International Knee Documentation Committee 2000 subjective form (IKDC2000). Linear regression models were developed using IKDC2000 scores at 6 months after ACL reconstruction as the dependent variable.ResultsFifty-five subjects had complete pre-operative data and IKDC2000 scores at 6 months after ACL reconstruction. Pre-operative involved quadriceps strength was a significant predictor for IKDC2000 scores 6 months after ACL reconstruction. Sex, meniscal injury, pre-operative BMI, and pre-operative involved quadriceps activation ratio were not significant predictors in the regression model.ConclusionsPre-operative quadriceps strength can predict IKDC2000 scores 6 months after ACL reconstruction. Deficits in pre-operative quadriceps strength influence self-reported function 6 months after surgery. Factors that are known to influence quadriceps strength and self-reported outcomes do not influence the relationship between pre-operative quadriceps strength and post-operative IKDC2000 scores.     

Comparison of muscle strength and neuromuscular control up to 1 year after anterior cruciate ligament reconstruction between patients with dominant leg and non-dominant leg injuries

BackgroundThere has not been an investigation to determine whether leg dominance affects the recovery of quadriceps and hamstring strength, muscle reaction time (acceleration time, AT), and postural stability after anterior cruciate ligament (ACL) reconstruction in recreational-level athletic patients.MethodsA total of 100 patients with isolated ACL injuries (58 patients had dominant leg injuries; 42 patients had non-dominant leg injuries) participated. All patients received an anatomical single-bundle ACL reconstruction using an auto-hamstring tendon graft without preoperative rehabilitation. Leg dominance was defined as the kicking leg. The quadriceps and hamstring strength, AT, and postural stability (overall stability index (OSI)) of both legs were assessed at three different time points (preoperative, 6 months, 12 months), using an isokinetic dynamometer and postural stabilometry system.ResultsAll patients in both groups showed gradual improvement in quadriceps and hamstring muscle strength in the operated legs up to 1 year postoperatively. However, the mean value of quadriceps strength was lower in the operated non-dominant leg than the operated dominant leg 6 months postoperatively (P = 0.048). The AT and OSI of the operated legs in both groups recovered significantly 6 months postoperatively compared with their preoperative values; however, the AT and OSI values after 6 and 12 months were similar.ConclusionQuadriceps strength of the operated non-dominant leg was lower than that of the operated dominant leg 6 months postoperatively; however, the strength of the quadriceps and hamstring muscles was not different after 12 months between the operated dominant and non-dominant legs. Clinicians and physical therapists should consider these results during early rehabilitation and identify effective protocols to enhance quadriceps strength, especially in patients with non-dominant leg injuries.     

Anterior cruciate ligament reconstruction with ultrasound-guided femoral nerve block does not adversely affect knee extensor strength beyond that seen with intravenous patient-controlled analgesia at 3 and 6 months postoperatively

BackgroundThis study aimed to investigate the effect of anterior cruciate ligament (ACL) reconstruction with an ultrasound-guided femoral nerve block (FNB) on knee extensor strength weakness 3 and 6 months, and graft rupture in the 1 year following ACL reconstruction.MethodsOne hundred and seven patients who underwent ACL reconstruction were included in this retrospective study. The patients were divided into two groups stratified by the method of postoperative pain management. The FNB group included 66 patients, and there were 41 patients in the intravenous patient-controlled analgesia (iv-PCA) group. The isokinetic peak torque of knee flexor and extensor was measured preoperative, 3 and 6 months after ACL reconstruction. Muscle strength measurements were performed using the BIODEX dynamometer at a velocity of 60°/s and 180°/s. Peak torque of knee extensor and flexor strength, estimated pre-injury capacity (EPIC), body weight ratio (BW), and graft rupture incidence were compared between the two groups.ResultsThere were no statistically significant differences in the knee extensor and flexor strength for all items at 3 and 6 months after ACL reconstruction. There was also not a statistically significant difference in the graft rupture incidence between the two groups: FNB group was two patients, 3.0% vs. iv-PCA group was one patient, 2.4% (p = 0.86).ConclusionACL reconstruction with ultrasound-guided FNB does not affect knee extensor strength at 6 months, nor graft rupture at 1 year postoperatively.     

Bilateral muscle atrophy after anterior cruciate ligament reconstruction in rats: Protective effects of anti-inflammatory drug celecoxib

BackgroundMuscle atrophy after anterior cruciate ligament (ACL) reconstruction occurs bilaterally and contributes to a decrease in muscle strength. However, effective treatment strategies for ACL reconstruction-induced muscle atrophy have not been established. We examined the effects of anti-inflammatory drug on muscle atrophy after ACL reconstruction.Materials and methodsRats were divided into groups according to treatment received: untreated control (n = 4), arthrotomy (n = 6), ACL transection (n = 7), ACL reconstruction (n = 8), and ACL reconstruction plus anti-inflammatory drug celecoxib (CBX; 50 mg/kg/day) administration (n = 8). At one-week post-surgery, the muscle fiber cross-sectional area (CSA) in the rectus femoris (RF) and semitendinosus (ST) was measured to assess muscle atrophy. In addition, we examined joint swelling and serum C‑reactive protein (CRP) levels to assess local and systemic inflammation, respectively.ResultsEach additional procedure (i.e., arthrotomy, ACL transection, and ACL reconstruction) gradually decreased the muscle fiber CSAs in the RF and ST on both operated and contralateral sides. The degree of muscle fiber atrophy on the operated side was larger than that detected on the contralateral side. Moreover, ACL reconstruction induced joint swelling on the operated side and tended to increase serum CRP levels. CBX lessened the RF atrophy on both sides and was associated with less joint swelling and a smaller increase CRP level; however, it did not affect ST atrophy on either side.ConclusionsAnti-inflammatory treatments after ACL reconstruction may be effective in lessening muscle atrophy in the quadriceps, but not in the hamstrings.     

The effect of meniscal pathology and management with ACL reconstruction on patient-reported outcomes,strength, and jump performance ten months post-surgery

BackgroundThe purpose of this study was to examine the differences in patient-reported outcome measures, isokinetic strength, plyometric ability and ability to meet return to play criteria ten months after anterior cruciate ligament (ACL) reconstruction surgery between those who underwent meniscectomy, those who underwent meniscal repair and those with no meniscal intervention alongside ACL reconstruction surgery.MethodsThree hundred and thirteen athletes with clinically and radiologically confirmed ACL ruptures were included in this study. Participants were grouped according to their intra-operative procedures (isolated ACL reconstruction surgery n = 155, ACL reconstruction surgery with meniscectomy n = 128, ACL reconstruction surgery with meniscal repair n = 30). Participants completed patient-reported outcome measures questionnaires (Marx Activity Rating Scale, the ACL Return to Sport after Injury and the International Knee Documentation Committee Score) and completed a battery of objective functional testing including isokinetic dynamometry and jump performance testing (countermovement jump and drop jump) between 9 and 11 months after surgery.ResultsNo significant between-group differences were identified in any metric relating to patient-reported outcome measures (p = .611), strength and jump measures (p = .411) or the ability to achieve symmetry-based return to play criteria (p = .575).ConclusionsClinically, these results suggest that concomitant meniscal surgery has no significant effects on patient-reported outcome measures, strength and jump metrics at the return to play stage post-operatively and can inform the pre-operative counselling of those awaiting ACL reconstruction surgery with likely meniscal intervention.     

Passing return to sports tests after ACL reconstruction is associated with greater likelihood for return to sport but fail to identify second injury risk

BackgroundA limited number of patients return to sport (RTS) after an anterior cruciate ligament reconstruction (ACLR) and patients who RTS have a relatively high risk for second ACL injury. The purpose of the current study was to compare the results of a test battery between patients who returned to the pre-injury level of sport (RTS group) and patients who did not (NO-RTS group).It was hypothesized that the RTS group showed better test results.MethodsSixty-four patients (age 27.8 ± 8.8 years) were included. The results of a multicomponent test battery (jump-landing task assessed with the Landing Error Scoring System (LESS), three hop tests, isokinetic strength test for quadriceps and hamstring) were compared between groups with a 2 × 2 ANOVA.ResultsThe RTS group showed a significantly lower LESS score (p = 0.010), significantly higher absolute scores on hop tests with both legs (injured leg: single leg hop test p = 0.013, triple leg hop test p = 0.024, side hop test p = 0.021; non-injured leg: single leg hop test p = 0.011, triple leg hop test p = 0.023, side hop test p = 0.032) and significantly greater hamstring strength in the injured leg (p = 0.009 at 60°/s, p = 0.012 at 180°/s and p = 0.013 at 300°/s). No differences in test results were identified between patients who sustained a second ACL injury and patients who did not.ConclusionPatients after ACLR with better jump-landing patterns, hop performance and greater hamstring strength have greater likelihood for RTS. However, our findings show that RTS criteria fail to identify patients who are at risk for a second ACL injury.     

Young athletes after ACL reconstruction with asymmetric quadriceps strength at the time of return-to-sport clearance demonstrate drop-landing asymmetries two years later

BackgroundQuadriceps strength asymmetry at the time of return-to-sport (RTS) after anterior cruciate ligament reconstruction (ACLR) contributes to altered landing mechanics. However, the impact of RTS quadriceps strength on longitudinal alterations in landing mechanics, a risk factor for poor knee joint health over time, is not understood. The purpose of this study was to test the hypothesis that young athletes with quadriceps strength asymmetry at the time of RTS clearance after ACLR would demonstrate asymmetric landing mechanics 2 years later compared to those without quadriceps strength asymmetry.MethodsWe followed 57 young athletes (age at RTS = 17.6 ± 3.0 years; 77% females) with primary, unilateral ACLR for 2 years following RTS clearance. At RTS, we measured isometric quadriceps strength bilaterally and calculated limb-symmetry indices [LSI = (involved/uninvolved)×100%]. Using RTS quadriceps LSI, we divided participants into High-Quadriceps (HQ; LSI ≥ 90%) and Low-Quadriceps (LQ; LSI < 85%) groups. Two years later, we assessed landing mechanics during a drop-vertical jump (DVJ) task using three-dimensional motion analysis. We compared involved/uninvolved limb values and LSI between the HQ and LQ groups using Mann-Whitney U tests.ResultsThe LQ group (n = 26) demonstrated greater asymmetry (lower LSI) during landing at 2 years post-RTS for knee flexion excursion (p = 0.016) and peak vertical ground reaction force (p = 0.006) compared to the HQ group (n = 28). There were no group differences in uninvolved or involved limb values for all variables (all p > 0.093).ConclusionYoung athletes after ACLR with quadriceps strength asymmetry at the time of RTS favored the uninvolved limb during DVJ landing 2 years later. These landing asymmetries may relate to long-term knee joint health after ACLR.     

Saphenous nerve injury after anterior cruciate ligament reconstruction: Reduced numbness area after ligamentoplasty using quadriceps tendon compared with hamstring tendon

PurposeInjury to the infra-patellar branches of the saphenous nerve (IPBSN) is the main neurological complication of anterior cruciate ligament (ACL) reconstruction procedures. Surgical technique using quadriceps tendon (QT) autograft allows a less invasive tibial approach potentially protecting the IPBSN. The aim of this study was to compare the numbness surface of the cutaneous area supplied by the IPBSN after ACL reconstruction using either hamstring tendon (HT) or QT autografts.MethodsThis was a retrospective comparative cohort study including 51 patients who underwent ACL reconstruction (27 QT and 24 HT) between January 2017 and April 2018. A sensory clinical evaluation was performed on each patient: length of the tibial scar, eventual numbness surface area and the type of sensory disorder were reported. To be considered as an IPBSN lesion, the numbness area had to spread at least one-centimeter away from the scar.ResultsThe average follow-up was 15 months. In the HT group, the numbness area surface measured 21.2 ± 19 cm² (0–77) and the scar length was on average 31.3 ± 5.6 mm. In the QT group, the numbness area was reduced to 5 ± 10 cm² (P = .0007) as well as the scar length (13.3 ± 2.8 mm, P < .0001). We counted five (17.8%) and 19 (76%) real IPBSN lesions in the QT and HT groups, respectively (P = .0002). Hypoesthesia was the main sensory disorder observed (87.5%).ConclusionNumbness area of the cutaneous surface supplied by the IPBSN after ACL reconstruction is reduced using QT autograft compared with HT autograft.     

Asymmetries in explosive strength following anterior cruciate ligament reconstruction

BackgroundDespite its apparent functional importance, there is a general lack of data regarding the time-related changes in explosive strength and the corresponding side-to-side asymmetries in individuals recovering from an ACL reconstruction (ACLR). The present study was designed to assess changes in the maximum and explosive strength of the quadriceps and hamstring muscles in athletes recovering from an ACLR.MethodsTwenty male athletes with an ACL injury completed a standard isometric testing protocol pre-ACLR, four and six months post-ACLR. In addition to the maximum strength (F_max), the explosive strength of quadriceps and hamstrings was assessed through four variables derived from the slope of the force–time curves over various time intervals (RFD_max, RFD₅₀, RFD₁₅₀ and RFD₂₅₀). Side-to-side asymmetries were calculated relative to post-ACLR measures of the uninvolved leg (“standard” asymmetries), and relative to pre-ACLR value of the uninvolved leg (“real” asymmetries).ResultsPre-ACLR asymmetries in quadriceps RFD (average 26%) were already larger than in F_max (14%) (p < 0.05). Six months post-ACLR real asymmetries in RFD variables (33–39%) were larger than the corresponding standard asymmetries (26–28%; p < 0.01). Average asymmetries in hamstrings' RFD and F_max were 10%, 25% and 15% for pre-ACLR and two post-ACLR sessions, respectively (all p > 0.05).ConclusionsIn addition to the maximum strength, the indices of explosive strength should also be included in monitoring recovery of muscle function following an ACLR. Furthermore, pre-injury/reconstruction values should be used for the post-ACLR side-to-side comparisons, providing a more valid criterion regarding the muscle recovery and readiness for a return to sports.     

Association between long-term quadriceps weakness and early walking muscle co-contraction after total knee arthroplasty

IntroductionQuadriceps weakness is one of the primary post-operative impairments that persist long term for patients after total knee arthroplasty (TKA). We hypothesized that early gait muscle recruitment patterns of the quadriceps and hamstrings with diminished knee performance at 3 months after surgery would be related to long-term quadriceps strength at 1 year after TKA.MethodsTwenty-one subjects who underwent primary unilateral TKA and 14 age-matched healthy controls were analyzed. At 3 months after TKA, the maximum voluntary isometric contraction of the quadriceps and a comprehensive gait analysis were performed. Quadriceps strength was assessed again at 1 year after surgery.ResultsQuadriceps muscle recruitment of the operated limb was greater than the non-operated limb during the loading response of gait (p = 0.03), but there were no significant differences in hamstring recruitment or co-contraction between limbs (p > 0.05). There were significant differences in quadriceps muscle recruitment during gait between the non-operated limbs of the TKA group and the healthy control group (p < 0.05). The TKA group showed a significant inverse relationship between one year quadriceps strength and co-contraction (r = ? 0.543) and hamstring muscle recruitment (r = ? 0.480) during loading response at 3 months after TKA.ConclusionsThe results revealed a reverse relationship where stronger patients tended to demonstrate lower quadriceps recruitment at 3 months post-surgery that was not observed in the healthy peer group. The altered neuromuscular patterns of the quadriceps and hamstrings during gait may influence chronic quadriceps strength in individuals after TKA.Level of evidenceIII.     

Predictors of patient satisfaction after primary hamstring anterior cruciate ligament reconstruction

BackgroundPredictors of patient satisfaction (PS) after anterior cruciate ligament (ACL) reconstruction are not well known. This study investigated predictors of PS and whether PS was associated with pre-injury level of sport participation, patient reported knee function and quality of life after ACL reconstruction.MethodsPatients who underwent primary hamstring ACL reconstruction between January 2015 and December 2017 were retrospectively evaluated. An online survey was used to evaluate PS (yes = satisfied, no = unsatisfied), duration of supervised postoperative rehabilitation, timing of return to pre-injury level of sport, pre-injury level of sport participation, patient reported knee function and quality of life. Preoperative, operative and postoperative variables were collected from the medical records.ResultsA total of 183 patients completed the survey at a median of 3.6 (1.5) years after ACL surgery. At final follow-up, 82% of patients were satisfied with the outcome. Preoperative (e.g. age) and operative (e.g. meniscal tear) variables were not predictors of PS (p > 0.05). Duration of supervised postoperative rehabilitation, timing of return to pre-injury level of sport and postoperative ACL injury were predictors of PS (p = 0.018, p = 0.016 and p < 0.001, respectively). Pre-injury level of sport participation was significantly higher in satisfied compared to unsatisfied patients: 44.7% (n = 67) versus 18.2% (n = 6) (p = 0.005). In addition, satisfied patients reported significantly higher patient reported knee function and quality of life compared to unsatisfied patients (p < 0.001).ConclusionThis study provided data on predictors of PS after primary ACL reconstruction. Furthermore, PS was associated with pre-injury level of sport participation, patient reported knee function and quality of life.     

Association between time from anterior cruciate ligament injury to reconstruction and morphological changes of the intercondylar notch using MRI and arthroscopy

BackgroundFew studies have measured the dimensions of intercondylar notch under direct arthroscopic visualization. The purpose of our study was to analyse the association between time from anterior cruciate ligament (ACL) injury to reconstruction and the morphological changes of intercondylar notch using magnetic resonance imaging (MRI) and arthroscopy.MethodsData was collected for patients who received knee arthroscopic surgery during 2014–2015. According to the time from ACL injury to reconstruction, these patients were divided into five groupsACL non-injured group (NI), acute rupture group (AR, <3 months), chronic rupture group 1 (CR1, 3–12 months), 2 (CR2, 1–5 years) and 3 (CR3, >5 years). MRI measurements of femoral condylar width (FCW) and intercondylar width (ICW) were undertaken before surgery. The widths at the base, middle and top of the intercondylar notch (ICWb, ICWm, ICWt, respectively) and the intercondylar notch height (ICH) were measured during arthroscopy. Intercondylar notch width index (NWI) and notch shape index (NSI) were then calculated and analysed among groups.ResultsA total of 272 patients were allocated to groups NI (n = 89), AR (n = 84), CR1 (n = 51), CR2 (n = 30) or CR3 (n = 18). Statistical analysis showed significant differences in ICW, ICWb, ICH, NWI and NSI between groups NI and AR. Among the groups with ACL-injury, ICWb and ICWt and NWI in group CR3 were statistically smaller than the other three groups (P = 0.004, 0.016, and 0.005, respectively).ConclusionsThe width of intercondylar notch had a negative correlation with time from ACL injury to reconstruction. Significant secondary notch stenosis was observed over 5 years after ACL rupture.     

The architecture of the ipsilateral quadriceps two years after successful anterior cruciate ligament reconstruction with bone–patellar tendon–bone autograft

BackgroundWe undertook a cross-sectional study to evaluate the pennation angle and muscle thickness of the vastus lateralis muscle in patients undergoing unilateral anterior cruciate ligament (ACL) reconstruction with bone–patellar tendon–bone autograft, and compared these values with the contralateral non-operated limb.MethodsTwenty three consecutive athletic males who underwent ACL reconstruction using the central third of the patellar ligament were evaluated at 25.9 ± 1.5 months. The International Knee Documentation Committee (IKDC) score was administered, and angles of pennation and muscle thickness were measured by ultrasonography.ResultsThere was no significant difference in the pennation angle of the operated leg comparing to the contralateral leg (12.5° ± 1.81° in the operated leg; 13.25° ± 2.40° after the test; p = 0.117). Quadriceps thickness in the operated leg was significantly decreased in all subjects compared to the contralateral leg (28.4 ± 5.3 mm in the operated leg; 32.7 ± 4.85 mm in the contralateral leg; p = 0.007).ConclusionsTwo years after surgery, there is no difference in pennation angle of the vastus lateralis when compared to the contralateral side in patients undergoing unilateral ACL reconstruction with bone–patellar tendon–bone autograft. There is a significant difference in quadriceps muscle thickness, which was less in the operated side on the operated side in all patients. Further studies are required to study the influence of muscle architecture on clinical outcome after ACL reconstruction surgery, and whether there are differences associated with the use of different grafts.Level of evidenceCase–control study; level IV.     

Clinical and electrophysiological assessment of injury to infrapatellar branch(es) of saphenous nerve during anterior cruciate ligament reconstruction using oblique incision for hamstring graft harvest: A prospective study

BackgroundOne of the complications of arthroscopic reconstruction of anterior cruciate ligament (ACL) using hamstring autograft is injury to the infrapatellar branch of the saphenous nerve (IPBSN) leading to loss of sensation around the knee. Its incidence varies according to the orientation of incision for hamstring graft harvest, with oblique incision having the lowest chance of this injury. Aim of this study was to assess clinically and electrophysiologically injury to IPBSN after ACL reconstruction using oblique incision for hamstring graft harvest.MethodsFifty patients that were scheduled to undergo arthroscopic ACL reconstruction were included. All the patients were evaluated both clinically and electrophysiologically preoperatively and at three weeks and six months postoperatively to determine injury to IPBSN. Patient satisfaction after surgery was also compared.ResultsIPBSN injury was found to be present in 12 out of 50 patients (24%). Both clinical and electrophysiological data correlated completely. The difference in the length of the skin incisions between IPBSN injured and IPBSN intact patients was found to be statistically significant (P = .0043). The difference in the satisfaction score between patients with injured and intact IPBSN was also found to be statistically significant (P = .02).ConclusionsOblique incision for hamstring graft harvest results in lower incidence of IPBSN injury and subsequent sensory loss when compared with similar studies with different skin incisions carried out in the past. Patients undergoing ACL reconstruction should be counseled preoperatively regarding this potential complication, and if this complication occurs, improvement can be expected with time.     

MRI signal intensity of anterior cruciate ligament graft after transtibial versus anteromedial portal technique (TRANSIG): A randomised controlled clinical trial

BackgroundTwo primary surgical femoral drilling techniques are used to reconstruct the anterior cruciate ligament (ACL): the transtibial (TT) technique and the anteromedial portal (AMP) technique. Currently there is no consensus on which surgical technique elicits the best clinical and functional outcomes. MRI-derived measures of the signal intensity (SI) of the ACL graft have been described as an independent predictor of graft properties. The purpose of this study was to assess MRI-derived SI measurements of the ACL graft one year after ACL reconstruction, in order to compare graft maturation of both AMP and TT ACL reconstruction techniques.MethodsThis randomised controlled trial included 33 patients admitted for primary unilateral ACL reconstruction. Primary outcome was MRI Signal intensity ratio (SIR) of the ACL graft one year after ACL reconstruction. Differences in MRI SIR were assessed on two MRI sequencies: sagittal Proton Density Turbo Spin Echo weighted images (PDTSE) and 3D T2 Gradient Echo (T2*) weighted images. Analysis of interobserver and intraobserver variability was conducted for the SIR measurements.ResultsNo difference in signal intensity of the graft was found between the TT and AMP techniques one year after ACL reconstruction (PDTSE p = 0.665, T2* p = 0.957). Both interobserver and intraobserver variability showed strong agreement (ICC 0.64–0.94).ConclusionNo differences in signal intensity of the graft on MRI were seen between the femoral drilling techniques one year after ACL reconstruction, suggesting similar graft maturation at that time. Follow-up studies are needed to determine whether graft intensity changes in the long term.Level of evidenceTherapeutic study with level of evidence I.     

Selective bundle reconstruction for symptomatic partial anterior cruciate ligament tears demonstrates good functional scores,high return to sport rates and a low re-tear rate

BackgroundThe treatment of symptomatic partial anterior cruciate ligament (ACL) tears remains controversial. This study investigated the clinical and functional outcome of patients undergoing selective posterolateral (PLB) or anteromedial (AMB) bundle reconstruction.Methods55 consecutive patients underwent partial bundle reconstruction, of which 45 (AMB = 17, PLB = 28) were included in the current analysis (62% male, mean age of 29.1 years). Patients were assessed at 12 and 24 months with patient-reported outcome measures (PROMs), graft laxity (KT-1000), knee extensor and flexor torque and a 4-hop battery. Limb Symmetry Indices (LSIs) were calculated. Return to sport (RTS) rates, re-operations and re-injuries were evaluated.ResultsHigh scoring PROMs were evident, with 62% and 84% of patients participating in pivoting sports at 12 and 24 months, respectively. Overall, 98% of patients demonstrated ‘normal’ knee laxity at 24 months. Mean LSIs for all hop tests were ≥ 90% at 12 and 24 months, with 76–87% of patients demonstrating LSIs ≥ 90% on the four hop tests employed at 12 months, which was 89–93% of patients at 24 months. A mean knee extensor torque LSI of 89% and 97% was observed at 12 and 24 months. Two ipsilateral re-tears (2/55, 3.6%, AMB = 1, PLB = 1) were observed over the 24-month period, with no contralateral ACL tears.ConclusionsHigh levels of physical function and RTS were observed in patients following partial bundle reconstruction, higher than that reported in the literature in patients undergoing ACLR, without evidence of instability and a low re-injury rate.     

A prospective double blinded randomized study of anterior cruciate ligament reconstruction with hamstrings tendon and spinal anesthesia with or without femoral nerve block

BackgroundCurrent literature supports the thought that anesthesia and analgesia administered perioperatively for an anterior cruciate ligament (ACL) reconstruction have a great influence on time to effective rehabilitation during the first week after hospital discharge.PurposeThe aim of this study is to answer the research question is there a difference in clinical outcomes between the use of a femoral nerve block with spinal anesthesia versus spinal analgesia alone for people undergoing ACL reconstruction?MethodsACL reconstruction with spinal anesthesia and patient sedation (Group one); and spinal anesthesia with patient sedation and an additional femoral nerve block (Group two). Patients were re-evaluated for pain, range of motion (ROM), active contraction of the quadriceps, and a Functional Independence Measure (FIM) scoring scale.ResultsSpinal anesthesia with a femoral nerve block demonstrates pain relief 6 h after surgery (VAS 0.37; p = 0.007). From the third (VAS = 4.56; p = 0.028) to the seventh (VAS = 2.87; p = 0.05) days after surgery, this same nerve blockage delivered higher pain scores. Patients had a similar progressive improvement on knee joint range of motion with or without femoral nerve block (p < 0.002). Group one and two had 23.75 and 24.29° 6 h after surgery and 87.81 and 85.36° of knee flexion after 48 h post op.ConclusionSpinal anesthesia associated with a femoral nerve block had no additional benefits on pain control after the third postoperative day. There were no differences between groups concerning ability for knee flexion and to complete daily activities during postoperative period.Level of EvidenceRandomized Clinical Trial Level I.     

Histological and cellular evaluation of anterior cruciate ligament

BackgroundWe hypothesized that the torn anterior cruciate ligament (ACL) demonstrates a great healing response after initial trauma and has competent cells leading to the healing but differs in its response based on the type of tear and duration of injury. This study aimed to evaluate the histological and cellular responses to the injured ACL.MethodsFifty-two tissue samples from the ACL were harvested from patients undergoing arthroscopy. Detailed histological and cellular examinations were performed for ligament angiogenesis, fibrocytes, and synovial tissue infiltration. We compared the cellular response to injury in partially and completely ruptured ACLs. The duration of ACL injury and its response to cellular characteristics were also examined. Immunohistochemical studies using cluster of differentiation 34 (CD34) staining was used to evaluate endothelial cells and fibrocytes.ResultsWe found a significantly higher density of synovial and ligament angiogenesis and fibrocytes at the torn end of ACL (Mann–Whitney, P < 0.050). Numerous fibrocytes were identified in complete ACL tears versus partial tears (Mann–Whitney = 0.020). Increased cellular proliferation was identified at the ruptured end of ACL remnant (Kruskal–Wallis, P < 0.050). The cellular proliferation of ruptured ACL decreased after 12 months.ConclusionsBased on our findings of the time-dependent decrease in the cellular response at the torn ends of the ACL, we recommend early intervention, preservation of the ACL remnant, and primary ACL repair or augmented reconstruction.     

Gait Biomechanics in Individuals Meeting Sufficient Quadriceps Strength Cutoffs After Anterior Cruciate Ligament Reconstruction

ContextQuadriceps weakness is associated with disability and aberrant gait biomechanics after anterior cruciate ligament reconstruction (ACLR). Strength-sufficiency cutoff scores, which normalize quadriceps strength to the mass of an individual, can predict who will report better function after ACLR. However, whether gait biomechanics differ between individuals who meet a strength-sufficiency cutoff (strong) and those who do not (weak) remains unknown.ObjectiveTo determine whether vertical ground reaction force, knee-flexion angle, and internal knee-extension moment differ throughout the stance phase of walking between individuals with strong and those with weak quadriceps after ACLR.DesignCase-control study.SettingLaboratory.Patients or Other ParticipantsIndividuals who underwent unilateral ACLR >12 months before testing were dichotomized into strong (n = 31) and weak (n = 116) groups.Main Outcome MeasuresMaximal isometric quadriceps strength was measured at 90° of knee flexion using an isokinetic dynamometer and normalized to body mass. Individuals who demonstrated maximal isometric quadriceps strength ≥3.0 N·m·kg⁻¹ were considered strong. Three-dimensional gait biomechanics were collected at a self-selected walking speed. Biomechanical data were time normalized to 100% of stance phase. Vertical ground reaction force was normalized to body weight (BW), and knee-extension moment was normalized to BW × height. Pairwise comparison functions were calculated for each outcome to identify between-groups differences for each percentile of stance.ResultsVertical ground reaction force was greater in the weak group for the first 22% of stance (peak mean difference [MD] = 6.2% BW) and less in the weak group between 36% and 43% of stance (MD = 1.4% BW). Knee-flexion angle was greater (ie, more flexion) in the strong group between 6% and 52% of stance (MD = 2.3°) and smaller (ie, less flexion) between 68% and 79% of stance (MD = 1.0°). Knee-extension moment was greater in the strong group between 7% and 62% of stance (MD = 0.007 BW × height).ConclusionsIndividuals with ACLR who generated knee-extension torque ≥3.0 N·m·kg⁻¹ exhibited different biomechanical gait profiles than those who could not. More strength may allow for better energy attenuation after ACLR.     

Knee extensor strength,hop performance,patient-reported outcome and inter-test correlation in patients 9–12 months after anterior cruciate ligament reconstruction

BackgroundHop performance and isokinetic knee extensor strength (IKES) asymmetry are associated with re-injury after anterior cruciate ligament reconstruction (ACLR). This study investigated deficits after ACLR, and which hop tests are most correlated with IKES and patient-reported outcome measures (PROMs).Methods50 patients were assessed 9–12 months after ACLR using the International Knee Documentation Committee (IKDC) and ACL Return to Sport after Injury (ACL-RSI) scores. Peak IKES and eight hop tests were assessed: single (SHD), triple (THD) and triple crossover (TCHD) hop for distance, 6 m timed hop (6MTH), single medial (MHD) and single lateral (LHD) hop for distance, single countermovement jump (SLCMJ) and timed speedy hop (SHT). The percentage of patients with limb symmetry indices (LSIs) < 90% was reported. Pearson’s correlations investigated the correlation between PROMs, IKES and hop LSIs.ResultsThe majority (80%) of patients had IKES LSIs < 90%. While 12–14% of patients demonstrated LSIs < 90% for the SHD, 6MTH, THD and TCHD, 52–80% demonstrated LSIs < 90% for the other hop tests. The IKES LSI was significantly different (p < 0.05) from all hop LSIs, besides the SLCMJ (p = 0.638). Large correlations were only observed between the IKES LSI and the SLCMJ (r = 0.82), MHD (r = 0.71) and LHD (r = 0.53). The SLCMJ, MHD and IKES LSIs demonstrated the largest significant correlations with the IKDC (r = 0.51–0.53) and ACL-RSI (r = 0.38–0.40).ConclusionsHop tests such as the MHD and SLCMJ may present a more practical alternative to quantifying peak IKES, especially in the absence of more sophisticated testing equipment. While not surrogates as such, these selective hop measures may better inform the clinician as to whether significant underlying quadriceps deficits are still present throughout the post-operative rehabilitation period.