Return to Sport After Criteria-Based Rehabilitation of Acute Adductor Injuries in Male Athletes: A Prospective Cohort Study

Abstract

Background: Despite being one of the most common sports injuries, there are no criteria-based rehabilitation programs published for acute adductor injuries.

Purpose: To evaluate return-to-sport (RTS) outcomes and reinjuries after criteria-based rehabilitation for athletes with acute adductor injuries.

Study design: Cohort study; Level of evidence, 2.

Methods: Male adult athletes with an acute adductor injury underwent a supervised, standardized criteria-based exercise rehabilitation program. Magnetic resonance imaging (MRI) was used to grade the injury extent from 0 (negative finding) to 3 (complete tear/avulsion). There were 3 milestones used to evaluate the RTS continuum: (1) clinically pain-free, (2) completion of controlled sports training, and (3) return to full team training. Subsequent injuries were registered within the first year.

Results: We included 81 athletes with an acute adductor injury (MRI grade 0: n = 14; grade 1: n = 20; grade 2: n = 30; grade 3: n = 17). Of these, 61 (75%) athletes achieved RTS milestone 1, 50 (62%) achieved RTS milestone 2, and 75 (93%) achieved RTS milestone 3. There were no statistical differences in the RTS duration between MRI grade 0, 1, and 2 at any RTS milestone; thus, these were grouped together as grade 0-2. The median time (interquartile range [IQR]) for athletes with grade 0-2 injuries to become clinically pain-free was 13 days (IQR, 11-21 days), to complete controlled sports training was 17 days (IQR, 15-27 days), and to return to full team training was 18 days (IQR, 14-27 days). For athletes with a grade 3 injury, median times were 55 days (IQR, 31-75 days), 68 days (IQR, 51-84 days), and 78 days (IQR, 68-98 days), respectively. The overall 1-year reinjury rate was 8%. Athletes who achieved RTS milestone 1 had a statistically significantly lower reinjury rate than athletes who did not (5% vs 21%, respectively; ϕ = -0.233; P = .048). Athletes who achieved RTS milestone 2 had a nonstatistically significantly lower reinjury rate than athletes who did not (6% vs 13%, respectively; ϕ = -0.107; P = .366).

Conclusion: We analyzed the results of a criteria-based rehabilitation protocol for athletes with acute adductor injuries. Athletes with an MRI grade 0-2 adductor injury were clinically pain-free after approximately 2 weeks and returned to full team training after approximately 3 weeks. Most athletes with an MRI grade 3 adductor injury were pain-free and returned to full team training within 3 months. Meeting the clinically pain-free criteria resulted in fewer reinjuries compared with not meeting the criteria.

Keywords: RTP; RTS; avulsion; groin; hip; muscle injury; muscle strain.

Figure 1.

Overview of the phases and focus of the standardized criteria-based rehabilitation protocol. Progression of the phases in the basic exercise part (groin and non-groin exercises) and in the running and sports function part could be performed independently. Criteria for both parts of the protocol had to be met before initiating on-pitch/on-court controlled sports training. Blue shading indicates the general exercise focus, and white shading indicates the phases and return-to-sport milestones. See Appendix 2 for further details.

Figure 2.

Nine groin exercises included in the protocol: (1 and 2) leg swings in hip abduction/adduction and hip extension/flexion with support, (3) standing hip circles, (4) standing hip adduction, (5) hip flexion, (6) trunk rotation, and (7) tension arc performed with elastic bands, (8) one-leg coordination exercise, and (9) the Copenhagen adduction exercise (see Appendix 2 for further description of the protocol).

Figure 3.

Flowchart of athlete inclusion for the 3 return-to-sport milestones.

Figure 4.

Duration in days from injury to each of the 3 different return-to-sport milestones visualized according to magnetic resonance imaging injury grading: (A) clinically pain-free (purple), (B) completion of controlled sports training (green), and (C) return to full team training (orange). Black lines represent median values, and dots represent individual athletes.