Postoperative Rehabilitation of Anterior Cruciate Ligament Reconstruction: A Systematic Review

Regional Patellar Tendon Strain in the Short- and Long-term After ACL Reconstruction Using Bone-Patellar Tendon-Bone Autograft

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) often involves harvesting a bone-patellar tendon-bone (BPTB) autograft. How graft harvest affects tendon strain across the 3 distinct regions (medial, lateral, and central) is not known.

PURPOSE

To (1) quantify strain in the 3 regions of the patellar tendon during 60% of maximum voluntary isometric contraction (MVIC) in 90° of knee flexion and (2) assess how effort level in 2 different knee joint angles (60° and 90°) impacts strain in the medial and lateral regions of the patellar tendon, in 2 cohorts of patients after ACLR using a BPTB autograft (one group <24 months after surgery and another group ≥24 months after surgery).

STUDY DESIGN

Descriptive laboratory study.

METHODS

Effort levels ranging from 20% to 100% of MVIC were performed at 90° and 60° of knee flexion on an isokinetic dynamometer, with simultaneous ultrasound imaging of tendon length to calculate regional strain. Linear mixed-effects models were used to evaluate regional strain at 60% of MVIC in 90° of knee flexion. The fixed effects of percentage of MVIC, joint angles, and time from surgery groups on patellar tendon strain were evaluated using separate models for the medial and lateral regions.

RESULTS

Fourteen participants in the short-term group (7.5 ± 1.9 months from surgery) and 15 participants in the long-term group (71.5 ± 16.5 months from surgery) were included. At 60% of MVIC in 90° of knee flexion, the short-term group demonstrated lower patellar tendon strain than the long-term group regardless of region (P < .01). The central region also had lower strain than the medial and lateral regions regardless of group (both P < .01). Finally, the rate at which strain increased with increasing effect levels differed between time from surgery groups in both medial and lateral regions.

CONCLUSION

The short-term group had lower strain in all regions of the patellar tendon after ACLR using BPTB autograft. The medial and lateral regions showed varying strain based on time from surgery and effort level. Varying knee joint angles and effort levels for graft site rehabilitation may have to be considered to target specific regions of the patellar tendon.

CLINICAL RELEVANCE

Clinicians should consider the time elapsed since surgery and the manipulation of knee angle as factors that can exert varying levels of strain on different regions of the patellar tendon after ACLR. Accelerating quadriceps strengthening to enhance strain distribution across the patellar tendon to promote tendon healing may be of benefit for optimizing postsurgery rehabilitation.

Return-to-sport tests: Do they reduce risk of re-rupture after anterior cruciate ligament reconstruction?

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is one of the most common knee injuries. Despite the effectiveness of reconstruction, re-rupture rates of up to 15 ​% have been reported. Static and dynamic test of strength and movement control have been used to determine when return to sports (RTS) is appropriate.

OBJECTIVE

To determine whether successfully passing return to sport (RTS) tests reduces the re-rupture rate.

METHODS

Retrospective cohort study. Patients who underwent ACL reconstruction (ACLR) from June 2018 to May 2023, and who performed RTS tests after rehabilitation, were analyzed. Patients who, in addition to ACLR, underwent extra-articular tenodesis, osteotomy, or multiligament injuries were excluded. RTS tests included the following: repeat sprint ability, dynamic valgus, proagility, unilateral counter movement jump (CMJ), isokinetic, triple hop test, and functional movement screen (FMS). All statistical analyses were performed with STATA version 18.0.

RESULTS

Ninety five patients underwent RTS tests after ACLR, with a follow-up time of 27.8 months. 71.6 ​% of patients were men with a mean age of 25.15 ​± ​10.7 years. The overall re-rupture rate was 13.68 ​% (13 patients). When comparing patients who passed and did not pass the RTS tests, there were no differences by sex (p ​= ​0.06) or age (p ​= ​0.11). The only statistically significant difference between the groups was the mean risk score (passed: 11.5 ​± ​0.7 vs. not passed: 15.5 ​± ​2.1; p ​< ​0.001). Patients with re-rupture were more likely to be from the non-passed group (passed: 0 ​% v/s not passed: 18.1 ​%; p ​= ​0.03), with a statistical power of 0.70.

CONCLUSION

Our records show that passing RTS test after an ACLR could guarantee the absence of re-rupture in the medium term.

LEVEL OF EVIDENCE

Level IV.

Rehabilitation Technologies by Integrating Exoskeletons, Aquatic Therapy, and Quantum Computing for Enhanced Patient Outcomes

Recent advancements in patient rehabilitation integrate both traditional and modern techniques to enhance treatment efficacy and accessibility. Hydrotherapy, leveraging water's physical properties, is crucial for reducing joint stress, alleviating pain, and improving circulation. The rehabilitation of upper limbs benefits from technologies like virtual reality and robotics which, when combined with hydrotherapy, can accelerate recovery. Exoskeletons, which support and enhance movement, have shown promise for patients with neurological conditions or injuries. This study focused on implementing and comparing proportional-integral-derivative (PID) and fuzzy logic controllers (FLCs) in a lower limb exoskeleton. Initial PID control tests revealed instability, leading to a switch to a PI controller for better stability and the development of a fuzzy control system. A hybrid strategy was then applied, using FLC for smooth initial movements and PID for precise tracking, with optimized weighting to improve performance. The combination of PID and fuzzy controllers, with tailored weighting (70% for moderate angles and 100% for extensive movements), enhanced the exoskeleton's stability and precision. This study also explored quantum computing techniques, such as the quantum approximate optimization algorithm (QAOA) and the quantum Fourier transform (QFT), to optimize controller tuning and improve real-time control, highlighting the potential of these advanced tools in refining rehabilitation devices.

Three-month functional training programme improves knee joint function in athletes post-ACL reconstruction surgery

OBJECTIVE

Rehabilitation and recovery duration following anterior cruciate ligament reconstructive surgery play a pivotal role in restoring optimal knee functionality in athletes. This study aimed to explore the impact of a 3-month functional training programme aligned with enhanced recovery after surgery on recuperation subsequent to anterior cruciate ligament reconstructive surgery.

DESIGN

A quasi-experimental study.

SUBJECTS

A cohort of 34 patients aged 14 to 24, who underwent anterior cruciate ligament reconstructive surgery and adhered to enhanced recovery after surgery protocols during the perioperative period, were allocated to an experimental group and a control group according to their eligibility, capacity, and willingness to engage in the functional training programme.

METHODS

The participants in the experimental group underwent a 3-month regimen of functional training following anterior cruciate ligament reconstructive surgery, whereas the control group followed a conventional recovery approach. Evaluations were conducted both prior to and following the 3-month recovery interval, utilizing the Y-Balance Test, Functional Movement Screening, and Isokinetic Knee Test.

RESULTS

Assessment outcomes of the Y-Balance Test, Isokinetic Knee Test, and Functional Movement Screening exhibited significant enhancement (p < 0.05) within the experimental group, as opposed to the control group. These findings underscore that those athletes who undertook the 3-month functional training regimen within the experimental group exhibited heightened dynamic balance capabilities, increased knee joint mobility, and enhanced stability compared with their counterparts in the control group.

CONCLUSION

Consequently, this underscores the efficacy of the 3-month functional training protocol aligned with enhanced recovery after surgery, as a means to effectively facilitate recuperation subsequent to anterior cruciate ligament reconstructive surgery.

Intermittent cyclic stretch of engineered ligaments drives hierarchical collagen fiber maturation in a dose- and organizational-dependent manner

Hierarchical collagen fibers are the primary source of strength in tendons and ligaments; however, these fibers largely do not regenerate after injury or with repair, resulting in limited treatment options. We previously developed a static culture system that guides ACL fibroblasts to produce native-sized fibers and early fascicles by 6 weeks. These constructs are promising ligament replacements, but further maturation is needed. Mechanical cues are critical for development in vivo and in engineered tissues; however, the effect on larger fiber and fascicle formation is largely unknown. Our objective was to investigate whether intermittent cyclic stretch, mimicking rapid muscle activity, drives further maturation in our system to create stronger engineered replacements and to explore whether cyclic loading has differential effects on cells at different degrees of collagen organization to better inform engineered tissue maturation protocols. Constructs were loaded with an established intermittent cyclic loading regime at 5 or 10 % strain for up to 6 weeks and compared to static controls. Cyclic loading drove cells to increase hierarchical collagen organization, collagen crimp, and tissue tensile properties, ultimately producing constructs that matched or exceeded immature ACL properties. Further, the effect of loading on cells varied depending on degree of organization. Specifically, 10 % load drove early improvements in tensile properties and composition, while 5 % load was more beneficial later in culture, suggesting a shift in mechanotransduction. This study provides new insight into how cyclic loading affects cell-driven hierarchical fiber formation and maturation, which will help to develop better rehabilitation protocols and engineer stronger replacements. STATEMENT OF SIGNIFICANCE: Collagen fibers are the primary source of strength and function in tendons and ligaments throughout the body. These fibers have limited regenerate after injury, with repair, and in engineered replacements, reducing treatment options. Cyclic load has been shown to improve fibril level alignment, but its effect at the larger fiber and fascicle length-scale is largely unknown. Here, we demonstrate intermittent cyclic loading increases cell-driven hierarchical fiber formation and tissue mechanics, producing engineered replacements with similar organization and mechanics as immature ACLs. This study provides new insight into how cyclic loading affects cell-driven fiber maturation. A better understanding of how mechanical cues regulate fiber formation will help to develop better engineered replacements and rehabilitation protocols to drive repair after injury.

Crossover effect of knee and ankle joint training on knee mechanics after ACL reconstruction: A randomized controlled trial

BACKGROUND

Anterior cruciate ligament (ACL) rehabilitation is a common intervention after ACL reconstruction. Since different types of exercise can influence muscle and kinematic parameters in diverse ways, the training order between the knee and ankle joints may also change gait parameters.

PURPOSE

This study aimed to investigate whether the training sequence of the knee and ankle joints (knee followed by ankle training or vice-versa) in an ACL reconstruction (ACLR) rehabilitation program has any effects on knee extension and flexion torques.

METHODS

Forty-two men (aged 20-30 years) with ACLR participated in this study. They were randomly allocated to receive one of two interventions: (A) knee joint training followed by ankle training or (B) ankle joint training followed by knee training. After five weeks (four weeks of intervention and one-week washout), participants crossed from one group to another for an additional four weeks. Knee extension and flexion torques were assessed during the stance phase of the gait cycle before and after the intervention program.

RESULTS

Two-way Mixed-design MANOVA showed that knee extension torque improved significantly in both groups after training (p = 0.001, Cohen's D = 0.65), while the knee flexion torque increased significantly only in group B (p= 0.001, Cohen's D = 0.97). When comparing both groups, patients of group B presented significant improvements in the post-training mean values of all tested variables compared with group A.

CONCLUSION

Starting a post-ACLR rehabilitation program with ankle training followed by knee training is better to improve knee flexion and extension torques during the stance phase of the gait cycle than starting the program by training the knee first, followed by the ankle. Future studies using a mixed-gender sample and different types of ACLR operations are necessary to examine whether similar improvements will happen as well as to test their effects on many sports activities.

Effect of open vs. closed kinetic chain exercises in ACL rehabilitation on knee joint pain, laxity, extensor muscles strength, and function: a systematic review with meta-analysis

Anterior cruciate ligament (ACL) injuries are common among physically active individuals, often requiring ACL reconstruction (ACLR) for recovery. Rehabilitating these injuries involves determining the appropriate timing for initiating open kinetic chain (OKC) exercises. Although OKC exercises are effective post-ACLR, their use in rehabilitation remains a subject of debate. Therefore, this study aims to conduct a systematic review to determine whether OKC or closed kinetic chain (CKC) exercises result in differences in laxity, strength of the knee extensor muscle group, function, and functional performance in ACL rehabilitation. Five electronic databases were searched for randomized controlled between-group trials (RCTs). Two reviewers independently evaluated the risk of bias using the PEDro scale. We performed a meta-analysis using a random-effects model or calculated mean differences (fixed-effect) where appropriate. Certainty of evidence was judged using the GRADE approach. The systematic literature search yielded 480 articles, of which 9 met the inclusion criteria. The evidence for all outcomes ranged from very low to low certainty. Across all comparisons, inconsistent results were found in outcome measures related to knee function between OKC and CKC exercises post-ACLR. A significant increase in quadriceps isokinetic strength was found in post-ACLR and ACL-deficient knees in favor of OKC exercises at 3 (p = 0.03) and 4 (p = 0.008) months, respectively. A significant decrease in knee laxity was observed in ACL-deficient knees in favor of OKC at 10 weeks (p = 0.01), although inconsistency was noted at 4 months. Finally, a significant decrease in pain was found in favor of early OKC compared to late OKC (p < 0.003). Additionally, in ACL-deficient knees, low load resistance training (LLRT) OKC showed no significant laxity difference compared to controls (p > 0.05). In contrast, high load resistance training (HLRT) OKC had less laxity than controls at 6 weeks (p = 0.02) but not at 12 weeks (p > 0.05). OKC exercises appear to be superior to CKC for improving quadriceps strength 3-4 months post-injury, whether as a part of conservative or post-surgery rehabilitation. On the other hand, OKC exercises seem to be either superior or equally effective to CKC for improving knee laxity, thus presenting their importance in being included in a rehabilitation protocol from the initial phase.

Systematic Review Registration

PROSPERO [CRD42023475230].

Intermittent Cyclic Stretch of Engineered Ligaments Drives Hierarchical Collagen Fiber Maturation in a Dose- and Organizational-Dependent Manner

Hierarchical collagen fibers are the primary source of strength in tendons and ligaments, however these fibers do not regenerate after injury or with repair, resulting in limited treatment options. We previously developed a culture system that guides ACL fibroblasts to produce native-sized fibers and fascicles by 6 weeks. These constructs are promising ligament replacements, but further maturation is needed. Mechanical cues are critical for development in vivo and in engineered tissues; however, the effect on larger fiber and fascicle formation is largely unknown. Our objective was to investigate whether intermittent cyclic stretch, mimicking rapid muscle activity, drives further maturation in our system to create stronger engineered replacements and to explore whether cyclic loading has differential effects on cells at different degrees of collagen organization to better inform engineered tissue maturation protocols. Constructs were loaded with an established intermittent cyclic loading regime at 5 or 10% strain for up to 6 weeks and compared to static controls. Cyclic loading drove cells to increase hierarchical collagen organization, collagen crimp, and tissue mechanics, ultimately producing constructs that matched or exceeded immature ACL properties. Further, the effect of loading on cells varied depending on degree of organization. Specifically, 10% load drove early improvements in mechanics and composition, while 5% load was more beneficial later in culture, suggesting a cellular threshold response and a shift in mechanotransduction. This study provides new insight into how cyclic loading affects cell-driven hierarchical fiber formation and maturation, which will help to develop better rehabilitation protocols and engineer stronger replacements.

The Interruption of Rehabilitation Following Anterior Cruciate Ligament Reconstruction due to COVID-19 Restrictions: Association With Return-to-Sport Testing

CONTEXT

Among many unanticipated changes, access to rehabilitation was disrupted during the onset of the COVID-19 pandemic. It is unclear how the timing of late-stage rehabilitation following anterior cruciate ligament with surgical reconstruction (ACLR) during the initial months of the pandemic affected outcomes. The purpose of this study was to compare physical performance outcome measures in patients following ACLR prior to and following COVID-19-related restrictions.

DESIGN

Retrospective cohort study.

METHODS

Data from patients who underwent return-to-sport testing following ACLR were analyzed based on date. December 2018 through March of 2020 (n = 66) was defined as the baseline period, and June through October 2020 (n = 27) was defined as the surveillance period. Outcome measures included single leg hop, triple hop, single leg vertical jump, and the lower-extremity functional test (LEFT). Linear mixed models were used to compare outcome measures before and after the onset of pandemic-related restrictions, clustered by sex and sport. A 1-way analysis of variance was performed to analyze the association between the number of virtual rehabilitation visits and outcome measures for subjects in the surveillance period.

RESULTS

Subjects in the surveillance period performed significantly worse in the LEFT (+7.88 s; 95% confidence interval, 1.11 to 14.66; P = .02) and single leg vertical jump on the unaffected side (-4.32 cm; 95% confidence interval, -7.44 to -1.19, P < .01), and performed better with single leg vertical jump symmetry (+6.3%; 95% confidence interval, 1.0% to 11.5%; P = .02). There were no other statistically significant differences. There was no significant association between having virtual rehabilitation visits and any of the performance outcomes.

CONCLUSIONS

There was a decline in physical performance outcome measures in patients following ACLR who did not attend regular in-person physical therapy sessions in the late-stage rehabilitation due to COVID-19-related restrictions. Other factors during this unique time period, such as access to training facilities or psychosocial stressors, may have also influenced outcomes.

Effect of kinesio-taping on the acute phase of the post-operative reconstruction of the anterior cruciate ligament: A randomized controlled trial

OBJECTIVES

Evaluate the Kinesio taping (KT) effects on reducing pain and edema on postoperative (PO) after anterior cruciate ligament (ACL) reconstruction.

DESIGN

Controlled and randomized clinical study.

SETTINGS

Individuals of both sexes, aged 18-45, underwent ACL reconstruction were randomized into intervention (IG; n = 19) and control (CG; n = 19) groups.

METHODS

Intervention consisted of KT bandage applications at hospital discharge for seven days, and on the 7th PO day, which was removed on the 14th PO. CG received specific instructions from the physiotherapy service. All volunteers were evaluations before and immediately after surgery, on the 7th and 14th PO day. Pain threshold (KgF), evaluated by algometer; edema (cm), evaluated by the perimetry measurements and volume of the lower limbs and the truncated cone test (ml) were the evaluated variables. The Student's t-test and Mann-Whitney U test were used to evaluate intergroup, analysis of variance (ANOVA) and Dunnett's test to evaluate intragroup.

RESULTS

Edema reduction and increased nociceptive threshold were significant in the 7th (p < 0.001; p = 0.003) and 14th (p < 0.001; p = 0.006) PO day in IG when compared to CG patients. IG perimetry levels, on the 7th and 14th PO were similar to preoperative period (p = 0.229; p = 1.000). IG nociceptive threshold value was similar on the 14th PO to before the surgery (p = 0.987). The same pattern did not occur in CG.

CONCLUSION

KT treatment reduced edema and increased nociceptive threshold in the 7th and 14th PO ACL reconstruction.

Comparative Study of Graft Healing in 2 Years after “Tension Suspension” Remnant-Preserving and Non-Remnant-Preserving Anatomical Reconstruction for Sherman Type II Anterior Cruciate Ligament Injury

Purpose: To evaluate the degree of graft healing after “tension suspension” reconstruction of “Sherman II” anterior cruciate ligament injuries versus non-remnant preserving anatomical reconstruction and to compare the clinical outcomes of the two procedures. Method: The clinical data of 64 patients were retrospectively included. There were 31 cases in the “tension suspension” remnant-preserving reconstruction group and 33 cases in the non-remnant-preserving anatomical reconstruction group. The International Knee Documentation Committee (IKDC) score, the Tegner score, and the Lysholm activity score were assessed preoperatively and at 6 months, 1 year, and 2 years postoperatively, respectively. The signal/noise quotient (SNQ) of the grafts was measured at 6 months, 1 year, and 2 years after surgery to quantitatively evaluate the maturity of the grafts after ACL reconstruction; the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the reconstructed ACL region of interest (ROI) were measured using DTI. Result: A total of 64 patients were included in the study. The mean SNQ values of the grafts in the 6 months, 1 year, and 2 years postoperative remnant-preserving reconstruction (RP) groups were lower than those in the non-remnant-preserving (NRP) reconstruction group, with a statistically significant difference (p < 0.05). At each postoperative follow-up, the SNQ values of the tibial and femoral sides of the RP group were lower than those of the NRP group; the SNQ values of the femoral side of the grafts in both groups were higher than those of the tibial side, and the differences were statistically significant (p < 0.05). At 6 months, 1 year, and 2 years postoperatively, the FA and ADC values of the grafts were lower in the RP group than in the NRP group, and the differences were statistically significant (p < 0.05); the IKDC score and Lysholm score of the RP group were higher than the NRP group, which was statistically significant (p < 0.05). Conclusion: For Sherman II ACL injury, the graft healing including ligamentization and revascularization at 2 years after the “tension suspension” remnant-preserving reconstruction was better than that of non-remnant-preserving anatomic reconstruction.

Loaded open-kinetic-chain exercises stretch the anterior cruciate ligament more than closed-kinetic-chain exercises: In-vivo assessment of anterior cruciate ligament length change

BACKGROUND

Usage of open-kinetic-chain (OKC) or closed-kinetic-chain (CKC) exercises during rehabilitation planning after anterior cruciate ligament (ACL) reconstruction has been debated for decades. However, the ACL elongation pattern during different rehabilitation exercises at different loadings remains unclear.

OBJECTIVES

This study aimed to determine the effects of OKC and CKC exercises on the length of ACL anteromedial bundle (AMB) and posterolateral bundle (PLB) to provide biomechanical support for making rehabilitation schedules.

DESIGN

Laboratory Descriptive Study.

METHOD

Eighteen healthy volunteers were asked to perform two OKC motions, including non-weight-bearing and 10 kg loaded seated knee extension (OKC-0, OKC-10), as well as two CKC motions, including box squat (BS) and deep single-legged lunge (Lunge). Techniques of 2D-to-3D image registration and 3D ligament simulation were used to quantify length changes of ACL.

RESULTS

The motion which led to the least and most ACL elongation were OKC-0 and OKC-10, respectively. The AMB and PLB were significantly longer in OKC-10 than those in OKC-0 during 0-60° and 0-55° of knee flexion (p < 0.01). Compared with reference length, the AMB and PLB were stretched during 0-30° and 0-10° respectively during OKC-10. During CKC exercises, the AMB and PLB were also stretched from 0 to 25°and 0-5°, respectively. Additionally, no significant difference was found in the length change of ACL bundles between BS and lunge.

CONCLUSIONS

OKC-0 may be safe for the rehabilitation program after ACL reconstruction, and loaded exercises shall be applied when restricted with >30° in early-stage rehabilitation.

Electromyostimulation in sport

Electromyostimulation (EMS) is a widely used therapeutic tool of low-frequency electrotherapy in several areas of rehabilitation, with gradual use increasingly in sports as well. The main goal of our article is to approach the use of EMS in sports based on available studies. EMS can be called as a training method used to obtain muscle activation through externally applied electric currents to the muscles to achieve a functional increase in sports performance by training fast motor units. Even if, based on the available study database, there are no clear conclusions regarding the effectiveness and application of EMS in the sense of sports, we can say that EMS represents one of the means by which we can influence muscle functionality, not only in terms of rehabilitation, but also as a possible way of increasing sports performance.

Rehabilitation And Advances In Surgical Reconstruction For Anterior Cruciate Ligament Insufficiency: What Has Changed Since The 1960s? - State Of The Art

Anterior cruciate ligament (ACL) insufficiency can be disabling, given the physical and sports activity constraints that negatively impact the quality of life. Consequently, surgery is the main approach for most active patients. Nonetheless, ACL reconstruction (ACLR) cannot be successful without adequate preoperative and postoperative rehabilitation. Since the 1960s, post-ACLR rehabilitation has evolved, mainly from advances in surgery, coupled with a better understanding of the biological concepts of graft revascularization, maturation and integration, which have impacted ACL postoperative rehabilitation protocols. However, new technologies do involve a definite learning curve which could affect rehabilitation programs and produce inconsistent results. The development of rehabilitation protocols cannot be defined without an accurate diagnosis of ACL injury and considering the patient's main physical demands and expectations. This article discusses how postoperative rehabilitation following ACLR has changed from the 1960s to now, focussing on surgical technique (type of tendon graft, fixation devices, and graft tensioning), biological concepts (graft maturation and integration), rehabilitation protocols (prevention of ACL injuries, preoperative rehabilitation, postoperative rehabilitation), criteria to return to sports, patient's reported outcomes and outcome. Although rehabilitation plays an essential role in managing ACL injuries, it cannot be fully standardised preoperatively or postoperatively. Preoperative and postoperative rehabilitation should be based on an accurate clinical diagnosis, patients' understanding of their injury, graft tissue biology and biomechanics, surgical technique, the patient's physical demands and expectations, geographical differences in ACL rehabilitation and future perspectives.

Ballet Rehabilitation: A Novel Return to Sport Protocol

Dance injuries and re-injuries are common but can be difficult to rehabilitate because of the unique demands and motor skills required. During tissue healing, pain resolves prior to tissue maturation and re-injury often occurs if the original injury is not properly rehabilitated.

The purpose of this narrative review is to analyze the existing literature addressing ballet injury, re-injury, and recovery, and to provide clinicians with timing guidelines for entering and implementing a Return to Sport (RTS) ballet rehabilitation protocol designed to prevent re-injury by progressive, sport-specific tissue loading. Thus far, a literature-based ballet-specific and body region-specific late-stage rehabilitation RTS protocol has not been established. The authors sought to address this literature gap by combining this comprehensive narrative review with our extensive clinical expertise to develop a late-stage rehabilitation RTS protocol to help guide medical clinicians treating injured ballet dancers.