Anterior knee symptoms after double-bundle ACL reconstruction with hamstring tendon autografts: an ultrasonographic and power Doppler investigation

Regional healing trajectory of the patellar tendon after bone-patellar tendon-bone autograft harvest for anterior cruciate ligament reconstruction

Graft site morbidities after bone-patellar tendon-bone (BPTB) autograft harvest for anterior cruciate ligament reconstruction (ACLR) negatively impacts rehabilitation. The purpose of this study was to establish tendon structural properties 1-month after BPTB autograft harvest compared to the uninvolved patellar tendon, and subsequently to quantify the healing trajectory of the patellar tendon over the course of rehabilitation. Patellar tendon morphology (ultrasound) and mechanical properties (continuous shear wave elastography) from 3 regions of the tendon (medial, lateral, central) were measured in 34 participants at 1 month, 3-4 months, and 6-9 months after ACLR. Mixed models were used to compare tendon structure between limbs at 1 month, and quantify healing over 3 timepoints. The involved patellar tendon had increased cross-sectional area and thickness in all regions 1-month after ACLR. Thickness reduced uniformly over time. Possible tendon elongation was observed and remained stable over time. Tendon viscosity was uniform across the three regions in the involved limb while the medial region had higher viscosity in the uninvolved limb, and shear modulus was elevated in all three regions at 1 month. Viscosity and shear modulus in only the central region reduced over time. Statement of Clinical Significance: The entire patellar tendon, and not just the central third, is altered after graft harvest. Tendon structure starts to normalize over time, but alterations remain especially in the central third at the time athletes are returning to sport. Early rehabilitation consisting of tendon loading protocols may be necessary to optimize biologic healing at the graft site tendon.

The thickness change ratio and preservation ratio of the infrapatellar fat pad are related to anterior knee pain in patients following medial patellofemoral ligament reconstruction

BACKGROUND

The infrapatellar fat pad (IPFP) lies extrasynovial and intracapsular, preserving the joint cavity and serving as a biochemical regulator of inflammatory reactions. However, there is a lack of research on the relationship between anterior knee pain (AKP) and the IPFP after medial patellofemoral ligament reconstruction (MPFLR). Pinpointing the source of pain enables clinicians to promptly manage and intervene, facilitating personalized rehabilitation and improving patient prognosis.

METHODS

A total of 181 patients were included in the study. These patients were divided into the AKP group (n = 37) and the control group (n = 144). Clinical outcomes included three pain-related scores, Tegner activity score, patient satisfaction, etc. Imaging outcomes included the IPFP thickness, IPFP fibrosis, and the IPFP thickness change and preservation ratio. Multivariate analysis was used to determine the independent factors associated with AKP. Finally, the correlation between independent factors and three pain-related scores was analyzed to verify the results.

RESULTS

The control group had better postoperative pain-related scores and Tegner activity score than the AKP group (P < 0.01). The AKP group had lower IPFP thickness change ratio and preservation ratio (P < 0.001), and smaller IPFP thickness (P < 0.05). The multivariate analysis revealed that the IPFP thickness change ratio [OR = 0.895, P < 0.001] and the IPFP preservation ratio [OR = 0.389, P < 0.001] were independent factors related to AKP, with a significant correlation between these factors and pain-related scores [|r| > 0.50, P < 0.01].

CONCLUSIONS

This study showed the lower IPFP change ratio and preservation ratio may be independent factors associated with AKP after MPFLR. Early detection and targeted intervention of the underlying pain sources can pave the way for tailored rehabilitation programs and improved surgical outcomes. LEVEL OF EVIDENCE LEVEL III.

Comparison of stiffness, elasticity and resilience values of ACL with autografts used instead of ACL in terms of texture analysis

Background

Anterior cruciate ligament (ACL) ruptures are one of the most extensively studied injuries in the field of orthopedics, but despite the extensive research, graft selection for ACL reconstruction remains a matter of debate. The present study aims to evaluate the stiffness and elasticity of native ACLs using texture profile analysis and compare results with those of autografts used in ACL reconstruction.

Methods

Included in the study were dissected 12 cadavers from which grafts were recovered. The graft characteristics, such as stiffness, elasticity and resilience, were measured using a TA.XT Plus Texture Analyzer.

Findings

Among the grafts studied, Achilles' tendon graft (0.70; 0.64) had the highest resilience in both males and females, while the greatest elasticity was identified in the patellar tendon graft (Male: 93 %; Female: 94 %) in all subjects. The highest stiffness value in males was recorded for the quadriceps tendon graft (2928.76 N), while the highest stiffness value in females was recorded for Achilles' tendon graft (2204.61 N).

Interpretation

According to the study data, the autografts that may be considered as an alternative to ACL were, listed in order of strength from high to low, the quadriceps, Achilles', patella and hamstring tendons in men, and the Achilles', quadriceps, patellar and hamstring tendons in women. It is worthy of note that the hamstring tendon graft, which is the most frequently preferred autograft in ACL reconstruction, was found to be the lowest in all parameters in both groups.

Relationship between the change in infrapatellar fat pad thickness assessed using ultrasonography and anterior knee pain on squatting after anterior cruciate ligament reconstruction

PURPOSE

Anterior knee pain (AKP) may occur after anterior cruciate ligament (ACL) reconstruction. The present study investigated the relationship between the change in infrapatellar fat pad (IFP) thickness assessed using ultrasonography (US) and AKP on squatting in patients after ACL reconstruction.

METHODS

Patients were enrolled 3 months after ACL reconstruction using the bone-tendon-bone (BTB) technique. Subjects were divided into the AKP group (numerical rating scale [NRS] score ≥ 1) and control group (NRS score < 1) using a NRS of pain on squatting, and intergroup comparisons were performed. On US evaluation, measurement angles of the knee joint were 0° and 30° in the supine position. The IFP between the femoral intercondylar notch and patellar tendon was measured on short-axis images. The changes in IFP thickness were calculated from values measured at different angles of the knee joint.

RESULTS

Twenty-one patients (mean age 24.9 ± 9.3 years) were included in the present study: 12 in the AKP group (9 males, 3 females) and nine in the control group (5 males, 4 females). A significant difference in the change in IFP thickness at 3 months was observed between the AKP and control groups (0.67 ± 0.44 mm vs. 1.84 ± 0.34 mm, p < 0.001). There was a negative correlation between the change in IFP thickness and the NRS score (r = - 0.720, p < 0.001) in reconstructed knees.

CONCLUSION

A smaller change in IFP thickness assessed using US after ACL reconstruction was identified as a factor contributing to AKP on squatting.

Lower donor site morbidity with hamstring and quadriceps tendon autograft compared with bone-patellar tendon-bone autograft after anterior cruciate ligament reconstruction: a systematic review and network meta-analysis of randomized controlled trials

PURPOSE

To perform a meta-analysis of RCTs evaluating donor site morbidity after bone-patellar tendon-bone (BTB), hamstring tendon (HT) and quadriceps tendon (QT) autograft harvest for anterior cruciate ligament reconstruction (ACLR).

METHODS

PubMed, OVID/Medline and Cochrane databases were queried in July 2022. All level one articles reporting the frequency of specific donor-site morbidity were included. Frequentist model network meta-analyses with P-scores were conducted to compare the prevalence of donor-site morbidity, complications, all-cause reoperations and revision ACLR among the three treatment groups.

RESULTS

Twenty-one RCTs comprising the outcomes of 1726 patients were included. The overall pooled rate of donor-site morbidity (defined as anterior knee pain, difficulty/impossibility kneeling, or combination) was 47.3% (range, 3.8-86.7%). A 69% (95% confidence interval [95% CI]: 0.18-0.56) and 88% (95% CI: 0.04-0.33) lower odds of incurring donor-site morbidity was observed with HT and QT autografts, respectively (p < 0.0001, both), when compared to BTB autograft. QT autograft was associated with a non-statistically significant reduction in donor-site morbidity compared with HT autograft (OR: 0.37, 95% CI: 0.14-1.03, n.s.). Treatment rankings (ordered from best-to-worst autograft choice with respect to donor-site morbidity) were as follows: (1) QT (P-score = 0.99), (2) HT (P-score = 0.51) and (3) BTB (P-score = 0.00). No statistically significant associations were observed between autograft and complications (n.s.), reoperations (n.s.) or revision ACLR (n.s.).

CONCLUSION

ACLR using HT and QT autograft tissue was associated with a significant reduction in donor-site morbidity compared to BTB autograft. Autograft selection was not associated with complications, all-cause reoperations, or revision ACLR. Based on the current data, there is sufficient evidence to recommend that autograft selection should be personalized through considering differential rates of donor-site morbidity in the context of patient expectations and activity level without concern for a clinically important change in the rate of adverse events.

LEVEL OF EVIDENCE

Level I.

Flexibility of infrapatellar fat pad affecting anterior knee pain 6 months after anterior cruciate ligament reconstruction with hamstring autograft

This study aimed to identify factors affecting anterior knee pain (AKP) after anterior cruciate ligament reconstruction (ACLR) with hamstring tendon autograft using ultrasonography. Forty-two patients were evaluated by ultrasound, 6 months after ACLR. The thickness of the superficial part of the infrapatellar fat pad was measured, as well as the thickness change ratio between the two angles. Color Doppler evaluated the rate of blood flow in the fat pad. AKP was assessed with the Kujala Scale. The correlations between AKP and age, body mass index, the thickness change ratio, and the grade of increased blood flow were examined. Independent variables showing significant correlations with AKP were used for multiple linear regression analysis. There were significant correlations between AKP and age (r = − 0.68), body mass index (r = − 0.37), the thickness change ratio of the fat pad (r = 0.73) and the grade of increased blood flow (r = − 0.42), respectively. Age and the thickness change ratio of the fat pad affected the AKP score (R² = 0.56). After ACLR, older age and a decrease in the thickness change ratio of the superficial area of the infrapatellar fat pad appear to affect post-operative AKP after 6 months.

Partial resection of the infrapatellar fat pad during anterior cruciate ligament reconstruction has no effect on clinical outcomes including anterior knee pain

BACKGROUND

Anterior knee pain (AKP) is a major complication that occurs after anterior cruciate ligament reconstruction (ACLR), even when hamstring tendon (HT) grafts are used. Damage to the infrapatellar fat pad (IPFP) during arthroscopy can cause AKP. The purpose of this study was to evaluate the influence of IPFP preservation on clinical outcomes, including AKP, in patients who underwent ACLR with HT autografts using the inside-out technique.

METHODS

Forty-two patients who underwent primary ACLR with HT autografts were prospectively assessed for 2 years after surgery. They were randomly selected to undergo treatment with as much intercondylar IPFP preservation as possible or with intercondylar IPFP resection to confirm the ACL origin on the femoral and tibial sides, especially the femoral footprint in deep flexion of the knee joint. The total IPFP volume was calculated using sagittal MR images before and 6 months after surgery. The patients completed a subjective knee score questionnaire and were assessed for patellar tendon tenderness and pain with the half-squat test or single-leg hop test at 6 months and 2 years postoperatively.

RESULTS

There were no differences in the patient characteristics, including age, sex, BMI, time from injury to surgery, and meniscus tear. The difference in the total size of the IPFP preserved was significant (P = 0.004). However, there were no significant differences in the subjective knee scores. Moreover, there were no differences in the clinical assessment parameters between the IPFP preservation and resection groups.

CONCLUSIONS

The size of the IPFP decreased more in the resection group than in the preservation group at 6 months after surgery. However, partial IPFP resection, which was used to better visualize the origin of the ACL, had no effect on the clinical outcomes, including AKP.

LEVEL OF EVIDENCE

Level II.

[Effect of vascularized peroneus longus tendon graft reconstruction on anterior cruciate ligament insertion in rabbits]

OBJECTIVE

To investigate the effect of vascularized peroneus longus tendon graft reconstruction on anterior cruciate ligament (ACL) insertion in rabbits.

METHODS

Eighty healthy New Zealand white rabbits were harvested to prepare ACL injury models and randomly divided into two groups ( n=40). The ACL was reconstructed with vascularized peroneus longus tendon graft in group A and peroneus longus tendon graft without blood supply in group B. The survival of animals and the healing of incision were observed after operation; the grafts were taken for gross and histological observations at 4, 8, and 16 weeks; the biomechanical test of the grafts was carried out to record the maximum tensile strength and incidence of ACL insertion rupture at 8 and 16 weeks.

RESULTS

All animals survived until the experiment completed. General observation showed that the tunnel was combined with grafts, the vascular infiltration was abundant, and no obvious boundary between the tunnel and grafts existed at 16 weeks in group A; there was still an obvious boundary between the tunnel and graft in group B. Histological observation showed that the collagen fibers between tendon and bone in group A increased gradually, the dense fiber connection was formed, and the "tidal-line" like structure similar to the normal ACL insertion was formed at 16 weeks; but the"tidal-line" like structure was not obvious in group B. Biomechanical test showed that there was no significant difference in the incidence of ACL insertion rupture at 8 and 16 weeks between group A and group B ( P=0.680; P=0.590), but the maximum tensile strength at 8 and 16 weeks were higher in group A than in group B ( t=18.503, P=0.001; t=25.391, P=0.001).

CONCLUSION

The vascularized peroneus longus tendon graft for ACL reconstruction can obviously promote the outcome of the ACL insertion.

Use of ultrasonography to evaluate the dynamics of the infrapatellar fat pad after anterior cruciate ligament reconstruction: a feasibility study

PURPOSE

There has been no specific study on the quantitative morphological changes that occur in the infrapatellar fat pad (IPFP) after anterior cruciate ligament (ACL) reconstruction. We used ultrasonography to evaluate the dynamics of the IPFP in knees after ACL reconstruction using the contralateral knees as controls.

METHODS

We enrolled 31 patients 3 months after they underwent ACL reconstruction. The thickness of the superficial part of the IPFP was measured using longitudinally oriented ultrasound images of the anterior part of both knees at 90° and 10° flexion. We then used these data to calculate the ratio of the change in thickness.

RESULTS

At 90° knee flexion, the superficial part of the IPFP was significantly thinner in the reconstructed knees (9.3 ± 3.4 mm) than in the contralateral knees (11.8 ± 4.6 mm). The thickness change ratio was significantly smaller in the reconstructed knees (188.6 ± 64.7%) than in the contralateral knees (249.7 ± 73.8%).

CONCLUSION

When assessed 3 months after ACL reconstruction, the thickness of the superficial part of the IPFP at 90° knee flexion and the thickness change ratio of the IPFP were both significantly lower in the reconstructed knees than in the contralateral knees.

A prospective study of coracoclavicular ligament reconstruction with autogenous peroneus longus tendon for acromioclavicular joint dislocations

BACKGROUND

Anatomic coracoclavicular (CC) ligament reconstruction (ACCR) provides good outcomes for Rockwood type III and VI acromioclavicular (AC) joint dislocations. Various grafts have been used, but complications from graft harvesting are not uncommon. This study examined the clinical and radiographic outcomes of patients with AC joint dislocations repaired with the autogenous anterior half of the peroneus longus tendon (AHPLT) to achieve ACCR.

METHODS

Patients with a Rockwood type III to V AC joint dislocation and magnetic resonance imaging of the disruption of the CC ligaments, as well as the AC capsule, were prospectively recruited. Patients received ACCR using an autogenous AHPLT graft and were evaluated clinically and radiographically preoperatively and at 1, 3, 6, and 12 months postoperatively.

RESULTS

A total of 18 patients (mean age, 51 years) were prospectively recruited and received an autogenous AHPLT graft ACCR. Fifteen patients completed clinical and radiographic follow-up examinations at 12 months. The mean Constant score (CS) was 51 preoperatively and 93 at 12 months (P <.005). No significant difference was noted at 12 months between the CS of the injured and contralateral shoulder. The mean American Orthopedic Foot and Ankle Society score at 12 months was 99, and this was not different from the value at any other time point. Loss of reduction occurred in 10 patients (56%), and tunnel widening was observed in 9 (50%), but neither was significantly correlated with functional outcome.

CONCLUSION

Autogenous AHPLT appears to be a reliable tendon graft source for CC ligament reconstruction.

Symmetry tensiomyographic neuromuscular response after chronic anterior cruciate ligament (ACL) reconstruction

PURPOSE

Quadriceps muscle weakness is common following anterior cruciate ligament (ACL) reconstruction. Tensiomyography is a recent method to assess muscle strength, and one that also enables evaluation of individual muscles. The purpose of this study was to evaluate motor unit recruitment and investigate the effects on mechanical and contractile characteristics of the quadriceps and hamstring muscles after chronic ACL reconstruction.

METHODS

This study recruited 20 participants: three males and seven females at 24 months after ACL reconstruction, and three males and seven females with no history of knee injury (control group). All participants underwent tensiomyographic assessment of each thigh muscle, bilaterally, to measure maximal displacement, delay time, contraction time, sustained time, and half-relaxation time. The following muscles were evaluated: vastus medialis, vastus lateralis, rectus femoris, semitendinosus, and biceps femoris. Mean normalized muscle peak torque, mean normalized maximum work done, mean angle to peak torque, and mean time to peak torque based on isokinetic peak torque measurements were calculated in both groups.

RESULTS

Maximal displacement of the vastus medialis on the ACL reconstruction side was significantly higher than for the non-ACL reconstruction side and for the control group (p = 0.026). Half-relaxation time for the vastus medialis and biceps femoris was significantly higher for both the ACLR and non-ACLR sides compared with the control group (p = 0.001). There were also significant differences in symmetry in the vastus medialis and biceps femoris when comparing results between the ACL reconstruction group and the control group (p = 0.034, p = 0.043, respectively).

CONCLUSIONS

The presence of strength and symmetry deficits in the vastus medialis and biceps femoris suggests the need for long-term post-operative training following ACL reconstruction. There are clinical relevant improvements of muscle response and velocity as well as muscle strength in patients with chronic ACLR.

LEVEL OF EVIDENCE

II.

Higher hamstring-to-quadriceps isokinetic strength ratio during the first post-operative months in patients with quadriceps tendon compared to hamstring tendon graft following ACL reconstruction

PURPOSE

The aim of this study was to compare isokinetic quadriceps and hamstring muscle strength in patients following anterior cruciate ligament (ACL) reconstruction who received either hamstring (HT) or quadriceps (QT) tendon autografts at two time intervals within the first year after surgery.

METHODS

One hundred twenty-four patients, 81 males (age 22.0 ± 6.2 years) and 43 females (age 20.9 ± 8.7 years), participated in this study. ACL reconstruction was performed with either quadriceps tendon autografts (QT; n = 61) or hamstring tendon autografts (HT; n = 63). Two isokinetic muscle strength tests (t1: 5.5 ± 1.2 months; t2: 7.6 ± 1.6 months) were performed at an angular velocity of 60°/s in both the injured and contralateral knees. An independent t test as well as a two-factor analysis of variance with repeated measurements was used. The significance level was set at p < 0.05.

RESULTS

A statistically significant lower knee extensor strength was observed in the QT group within one year after surgery (p < 0.001). Additionally, data showed a significant higher H/Q ratio in QT patients compared to the HT group at t1 (p < 0.001) and t2 (p = 0.001) as well as a significant effect over time (p < 0.001) and interaction effect of time and graft (p = 0.007). Side-to-side values for extensor muscle strength were significantly (p < 0.001) greater in HT graft patients, while QT patients showed significantly (p < 0.001) greater values for flexor muscle strength at both time points of isokinetic testing, respectively.

CONCLUSION

The results of this study indicate that graft choice has an impact on extensor strength in the first months after ACL reconstruction; however, there is no impact on flexor strength. The finding of a higher H/Q ratio in patients with QT grafts within the first months following surgery is possibly of clinical relevance. This may potentially be associated with lower stress on the maturing ACL graft. Furthermore, normal thigh strength can be restored over time.

LEVEL OF EVIDENCE

III.