USE OF AN UPPER EXTREMITY FUNCTIONAL TESTING ALGORITHM TO DETERMINE RETURN TO PLAY READINESS IN COLLEGIATE FOOTBALL PLAYERS: A CASE SERIES

Abstract

Background/Purpose:

Return to play decision making for upper extremity injuries is challenging due to a lack of evidence-based protocols and testing. Current guidelines utilize tests and measures with minimal evidence on re-injury risks and prediction. The purpose of this case series is to highlight a functional testing algorithm for upper extremities injuries and the outcomes for the patients that followed it.

Study Design:

Case series

Case descriptions:

Six subjects (18 – 21 years old) who underwent shoulder capsulolabral repair secondary to recurrent instability and/or unyielding pain are included. All subjects underwent a criterion-based rehabilitation program before being assessed with the authors’ upper extremity functional testing algorithm. The upper extremity functional testing algorithm consists of measures of active range of motion (AROM), passive range of motion (PROM), peak isometric force, a fatigue testing battery, and the closed kinetic chain upper extremity stability test (CKCUEST) to assess readiness for return to sport.

Outcomes:

All athletes achieved > 90% symmetry on at least two out of three tests during a fatigue testing protocol and at least 25 touches on the CKCUEST. All of the athletes returned to unrestricted football the season following surgical intervention. None of the athletes sustained an additional glenohumeral subluxation, dislocation, or upper extremity injury requiring surgical intervention for the remainder of their athletic careers (six years).

Discussion

The presented cases help to illustrate the effectiveness of the upper extremity functional testing algorithm to assess return to sport readiness for male collegiate football athletes. The algorithm included testing of AROM/PROM and strength that is typically used, but also included the CKCUEST and fatigue testing to further challenge and assess the upper extremity prior to returning to sports.

Level of Evidence:

4

BACKGROUND AND PURPOSE

Shoulder injuries within American football are common especially at the elite college level. Prevalence of prior shoulder injuries is reported at 50%- 51.9% for college athletes attending the NFL combine.^1,2 Of further note, shoulder labral injuries make up 14.6% - 14.9% of all injuries with posterior being most common at 54% – 70% of tears noted.^1-4 Of those that suffer from a labral tear, surgical repair is becoming increasingly popular due to reduced rates of recurrent instability at 3% - 32% when compared to non-operative treatments and high levels of return to play at same level or higher reported to be at 64% - 85.4%.^5-12

Following a surgical repair of the shoulder labrum, it is the current standard of care that all athletes are seen for rehabilitation to improve mobility and stability in the shoulder prior to returning to play. The different tasks that an athlete's shoulders must endure during a football game place large demands on both the static and dynamic stabilizers. More specifically, the task of blocking places the shoulders in vulnerable positions. During blocking, players are instructed to elevate the shoulders above 90 degrees and “triangulate” their forces to one side of the opposing player in order to throw off their center of mass and slow them down.¹³ The elevated position along with large forces that the upper quarter must withstand put athletes at increased risks.

Due to these heavy loads, physical therapists are continually searching for functional tests to best predict return to play readiness and safety. Unlike the lower extremity, various upper extremity functional tests have been described in the literature, but no single test is consistently used for determining return to play readiness. Upper extremity tests such as the seated shot put test and the upper extremity Y-balance test have been utilized in prior research. While these tests utilize different aspects of upper extremity power and stability, no correlations have been studied in regard to injury risks to date, making them less utilized in return to sport decision making.^14,15

One test that is currently being utilized within the upper extremity literature is the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), which was introduced in 2000 by Goldbeck and Davies.¹⁶ The CKCUEST has been reported to demonstrate high test-retest reliability in a group of healthy male college students, with an ICC of 0.922.¹⁶ This test correlates with peak isometric shoulder strength measured using hand-held dynamometry of shoulder elevation, external rotation, and internal rotation (r = 0.7, 0.7, and 0.8, respectively; p < 0.05);¹⁷ peak isokinetic ER/IR strength (r = 0.9) and grip strength (r = 0.8);¹⁸ and other upper extremity functional tests, namely the upper quarter Y-Balance Test (r = 0.49 for non-dominant [ND] and 0.43 for the dominant upper extremity, both p < 0.05),¹⁹ and the single arm shot-put test (r = 0.66 for ND and 0.63 for the dominant upper extremity, both p < 0.05).²⁰ This demonstrates that the CKCUEST assesses several facets simultaneously, and has been validated against other functional tests for the upper extremity. Additionally, Pontillo et al²¹ found that a cutoff of 21 touches would predict in-season shoulder injuries with a sensitivity of 0.83, specificity of 0.79 and odds ratio of 18.75 in collegiate football players (p < 0.05). To the authors’ knowledge, this is the only upper extremity functional test which has been shown to be useful for injury prediction when used in healthy athletes.

Another aspect with return to sport decision making that has to be considered is the influence of muscle fatigue affecting the integrity of the repair. Although fatigue testing assesses a different component of muscle capacity than dynamometer testing, it is not commonly used in the clinic secondary to the paucity of literature supporting its use. However, since athletic tasks require repetitive use of the upper extremities, the authors suggest that it is important to assess as muscular fatigue can impede sensory motor function and may increase the risk of shoulder injury during activity. Okoroha et al.²² and Mulla et al.²³ both found changes in upper extremity kinematics following fatigue that could increase stresses across the upper extremity. Additionally, Pontillo et al.²⁰ found that preseason fatigue testing, when combined with functional testing, is predictive of in season upper extremity injuries in the collegiate football athlete population.

Current guidelines utilize tests and measures with minimal evidence on re-injury risks and prediction, and are based largely on expert opinion. The purpose of this case series is to highlight a functional testing algorithm for upper extremities injuries and the outcomes for the patients that followed it.

CASE SERIES DESCRIPTION

All subjects were varsity Division I football players who had undergone a capsulolabral repair secondary to recurrent instability and/or unyielding pain. All cases were seen by the primary author for the length of their course of care. A description of the subjects is provided in Table 1.

Table 1.

Description of Cases.

Athlete	Year	Age	Position	Surgical Repair	Previous dislocations	# sessions
1	Freshman	18	Wide receiver	Posterior	3	20
2	Freshman	19	Cornerback	Anterior	1	27
3	Sophomore	20	Defensive end	Anterior and posterior	multiple	42
4	Freshman	18	Defensive line	Posterior	multiple	40
5	Junior	21	Fullback	Anterior and posterior	multiple	20
6	Sophomore	20	Defensive back	SLAP	multiple	16

EXAMINATION

Initial Assessment

Initial assessments were performed according to the post-operative protocol and typically consisted of assessment of the uninvolved upper extremity, and PROM measures of the involved upper extremity. This typically began four to five weeks post-operatively. Prior to starting formal physical therapy, the athletes were immobilized in a sling, and initiated range of motion (passive elevation, pendulums) at approximately three weeks post-operatively.

Interventions

All athletes were progressed according to criterion – based guidelines, while respecting the specific healing structures (i.e., avoiding posterior shear forces in the early phases after the repair of posterior structures, etc.). Range of motion and strength interventions progressed from non-provocative to provocative positions. The rotator cuff and scapular musculature was trained for both strength and endurance (e.g., sustained holds, repetitions to fatigue). ­Proprioception/neuromuscular training (NMT) and closed kinetic chain activities were incorporated in all phases of rehabilitation. Open chain NMT consisted of manual (e.g., rhythmic stabilization) and self-perturbation methods. Closed chain stabilization was progressed from minimal posterior sheer positions (i.e., hand in contact with the wall in standing) to full body weight weightbearing through the involved upper extremity. Plyometrics were incorporated when the athlete could perform overhead strengthening without pain or difficulty. In the final phases, controlled falls onto a physioball were incorporated to mimic the biomechanical demands of the sport.²¹ The primary author communicated with the athletic training staff and strength coaches on a weekly basis; strength and conditioning restrictions were communicated to maximize conditioning and lower body/core work in the early phases of rehabilitation, and facilitate safe return to weightlifting in the later phases.

RTP Assessment

All athletes included in this case series underwent surgical intervention during the season or immediately post-season (October-December). The goal for all athletes was unrestricted return to play by the following season (August of the next year). Return to play evaluations were performed prior to summer break (typically beginning of May, or five to seven months post-operatively), and again prior to the beginning of the season (August, eight to ten months post-operatively) for five of the six athletes. As these athletes were not on campus nor undergoing formal treatment over the break, the pre-break assessment was used to identify if any residual deficits persisted, and the pre-season assessment was to ensure all previous impairments were assessed and that the athletes did not regress over break.

These return to play assessment consisted of:

• Active range of motion: Forward elevation in the plane of the scapula (FE), external rotation at 0 ° (ER 0), ER at 90 ° abduction (ER 90), internal rotation up back (FIR).

• Passive range of motion: Forward elevation in the plane of the scapula (FE), external rotation at 0 ° (ER 0), ER at 90 ° abduction (ER 90), internal rotation at 90 ° abduction with the scapula stabilized (IR 90).

• Strength testing: Peak isometric force was measures by handheld dynamometer (Microfet 2; Hogan Health, Salt Lake City, Utah; measurement range 0 to 136 kg of force; accuracy within 1%) and consisted of FE at 90 °; ER at 0 ° and 90 °; IR at 0 ° and 90 °; prone middle (MT) and lower trapezius (LT). For internal rotation, with the athlete standing, the athlete's arm was at 0 ° abduction/flexion, neutral internal/external rotation, and the elbow bent to 90 °. The dynamometer was placed on the volar distal forearm, and the examiner stabilized the athlete's arm at the distal medial humerus. For external rotation, the athlete arm was at 0 ° abduction/flexion, neutral internal/external rotation, and the elbow bent to 90 °. The dynamometer was placed on the dorsal distal forearm, and the examiner stabilized the subject's arm at the distal lateral humerus. These were repeated for the 90 ° abduction/90 ° external rotation position. For elevation, with the athlete standing, the athlete's upper extremity was in 90 degrees of elevation in the plane of the scapula with neutral internal/external rotation. The dynamometer was placed at the athlete's radial styloid, and the tester stabilized the upper extremity at the scapula. Prone middle and lower trapezius were performed at 90 ° abduction, neutral ER/IR and 120 ° elevation, full ER, respectively. These procedures were found to have good test–retest reliability, excellent intra- and interrater reliability (previously reported ICC: 0.85-0.99).²³ The test positions were described to each athlete, and their upper extremity manually placed in the correct position if necessary. For all tests, the athlete was asked to meet the tester's resistance. If the athlete upper extremity deviated from the test position/compensatory strategies were seen, the athlete repeated the test. Resistance was held for five seconds; two trials for each position were collected. This was done to allow adequate recovery time between the tests, thus fatigue from one test was not likely to influence performance on the subsequent tests.

The two trials per direction were assessed and averaged. Strength is reported as % symmetry.

Fatigue testing: Fatigue testing was assessed in three positions, according to the protocol outlined in Pontillo et al.²⁰ The prone-y test assesses the endurance of the middle and lower trapezius muscles; the scaption test assesses the rotator cuff and scapular stabilizers; the standing cable press assesses the pectoralis major, latissimus dorsi, and deltoid muscles. Each test is performed once per side for each subject to minimize any one portion of the test affecting subsequent portions of the testing session. Testing to fatigue was performed in time to a metronome (60 Hz). Task failure was defined as (1) unable to keep time to the metronome, (2) demonstration of compensatory strategies, or (3) inability to achieve the operationally defined testing positions as stated (less than 90 ° of elevation for standing cable press and scaption, below parallel to the floor for the prone-y). Both extremities were tested and percent symmetry was calculated.

Standing cable press: Resistance was set to 30% of the athlete's body weight. While holding a cable pulley handle, the subject was instructed to perform a smooth, controlled pressing action. The terminal arm position was 90 ° of flexion, neutral horizontal abduction/adduction, and full pronation (Figure 1).

Figure 1.

Standing Cable Press, performed at 30% BW. Terminal position.

Scaption: 5% of body weight was utilized for resistance. The athlete started with their arm by their side; and the end position was 90 ° of elevation in the scapular plane, with neutral internal/external rotation (Figure 2).

Figure 2.

Scaption, performed at 5% BW. Terminal ­position.

Prone-y: 3% of the athlete's bodyweight was used for resistance. The athlete started prone with their upper extremity off the table; the end position was 120 ° of abduction and full external rotation (Figure 3).

Figure 3.

Prone-y, performed at 3% BW. Terminal ­position.

CKCUEST: This test was performed according to the original description by Goldbeck and Davies.¹⁶ Two tapelines were placed 36 inches apart. The subject started in a standard push-up position, with one hand on each tapeline (Figure 4a). The subject was to touch one tapeline with the opposite hand, and repeat (Figure 4b). The score is the number of touches achieved in 15 seconds. The test was performed twice with a self-selected rest between trials. The higher of the two trials was utilized.

Figure 4.

CKCUEST: Start position (a) and test in progress (b).

All testing was performed in the same order to standardize the examination.

Patient-Reported Outcomes

FOTO (Focus On Therapeutic Outcome) was used at initial evaluation and discharge (Table 2).

Table 2.

Outcome scores at initial evaluation and discharge.

	FOTO IE	FOTO DC
1	52	91
2	76	NA
3	34	91
4	71	88
5	49	91
6	76	91

FOTO = Focus on Therapeutic Outcomes score; IE = initial evaluation; DC = discharge

Results/Outcomes

Strength, fatigue and functional test scores are presented in Table 3. All athletes achieved a CKCUEST of at least 25 touches, and fatigue symmetry of  > 90% in at least two of three of the test positions. For any strength or fatigue testing measure assessed at less than 90% symmetry, the athlete was given a specific home exercise program to target the deficit to be performed for the remainder of the season. Range of motion values are presented in Appendix 1.

Table 3.

Isometric Strength, Fatigue Testing, and CKCUEST Scores at final assessment.

	HD	Involved	Final Isometric Strength Symmetry							Final Fatigue			CKCUEST (number of touches)
			FE	ER 0	IR 0	ER 90	IR 90	MT	LT	SCP	Scaption	Prone Y
1	R	R	105%	106%	100%	113%	112%	100%	92%	106%	96%	109%	25
2	R	R	100%	100%	100%	145%	131%	100%	113%	110%	122%	86%	25
3	R	L	100%	120%	132%	95%	95%	111%	100%	90%	92%	94%	30
4	R	B (L surgical)	100%	93%	95%	91%	100%	100%	100%	96%	100%	80%	33
5	R	L	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	27
6	R	B (R surgical)	90%	87%	111%	115%	126%	76%	87%	111%	100%	107%	26

Strength and fatigue test scores in % symmetry (with involved shoulder as the reference); CKCUEST = closed kinetic chain upper extremity stability test, recorded in number of touches.

HD = hand dominance; L = left; R = right; B = bilateral; FE = forward elevation; ER=external rotation; IR = internal rotation; MT = middle trapezius; LT=lower trapezius; SCP = standing cable press

The long-term goals to allow return to sport for all athletes were as follows:

1. No pain with activity

2. ROM WFL (either = to pre-op or contralateral shoulder except in cases of hypermobility)

3. Strength testing by HHD: > 95% symmetry

4. Fatigue protocol: > 90% symmetry

5. CKCUEST: > 21 touches (knowing < 21 predictive of shoulder injury)

6. Unrestricted return to football, including strength and conditioning

All examination, re-evaluation, and return to play assessments were conducted by the primary author. All athletes returned to unrestricted football (including strength and conditioning for the following season). By the end of their collegiate football careers (i.e., after the last season), or if applicable, their professional career, none of the athletes had sustained an additional dislocation or subluxation or upper extremity injury which required surgical intervention (6 years to date).

DISCUSSION

Playing American football lends itself to many different types of shoulder injuries with shoulder labral tears making up to 14.9% of shoulder injuries.^1-3 While this is a low percentage of the overall upper extremity injury rate, labral injuries are increasingly leading to surgical interventions due to the reduced rates of recurrent instability when compared to non-operative management.^5-12 Following surgical repairs, athletes are routinely sent to physical therapists and athletic trainers to help them rehabilitate and prepare for return to sports.

At the end of an athlete's rehabilitation, physical therapists and athletic trainers use objective measures along with subjective reports to help them determine when it is safe to return to sport activities. Currently, there is only one published upper extremity return to play protocol. Davies et al²⁵ proposed a functional testing algorithm for the upper extremity that included strength testing, range of motion testing, the CKCUEST, one-arm seated shot-put test, along with other functional throwing tests prior to returning to more specific sport tasks. This algorithm is based on the author's opinion along with research based on the individual tests.

The authors propose that a battery of isometric peak force measures, fatigue testing, and functional testing be considered for use as a return to play protocol, based on the success of the athletes in this case series, and the absence of re-injury (Table 4). Additionally, this specific testing battery has demonstrated the ability to predict upper extremity injuries in football athletes.²⁰ All of the athletes included in this case series were able to return to their previous level of competition, and furthermore, able to compete for the remainder of their athletic career without sustaining an additional shoulder injury (up to six year follow-up). All of the athletes were able to achieve greater than 90% symmetry in at least two out of the three fatigue tests, and all scored at least 25 touches on the CKCUEST. The strength and fatigue symmetry were set to 95 and 90%, respectively, to ensure that the difference between the involved and uninvolved upper extremity would be subjectively indistinguishable to the athlete, irrespective of arm dominance. Arm dominance was recorded, but not accounted for in RTP decisions, as football skills require bilateral upper extremity demands. Despite the restrictiveness of the criteria, the authors believe that clinicians should consider employing this until future research elucidates the optimal percentages to determine RTP readiness.

Table 4.

Author's Proposed Upper Extremity Return to Play (RTP) Criteria.

	RTP Criteria	Notes
Pain	None
AROM/PROM	Equal to pre-op/uninjured or contralateral shoulder	Exception: hypermobility cases
Peak Isometric Force Symmetry	> 90% symmetry	FE at 90 °; ER at 0 ° and 90 °; IR at 0 ° and 90 °; prone MT and LT
Fatigue Testing Battery	> 90% symmetry	Standing cable press (30% BW); scaption (5% BW); prone-Y (3% BW)
CKCUEST	> 21 touches	For other sports: compare to published normative values
Other	Completion of ISP, position specific field tests, and/or sport specific strength and conditioning loads	Sport/position specific; if applicable

AROM/PROM = active range of motion/passive range of motion; FE = forward elevation, ER = external rotation; IR = internal rotation; MT = middle trapezius; LT = lower trapezius; BW=body weight; CKCUEST = closed kinetic chain upper extremity stability test; ISP=interval sports program

The authors believe that the addition of functional testing and fatigue testing is imperative for a comprehensive return to play examination. The proposed testing battery simulates the forces that an athlete would have to sustain during practice or competition better than solely utilizing isometric strength testing, in that endurance, stability, and agility are also assessed. The authors advocate that this return to play protocol could be used not only football athletes, but for athletes across various sports, as all muscle groups in the shoulder girdle are addressed, and several facets of upper extremity function are simultaneously assessed (strength, endurance, stability, and agility). Furthermore, choosing resistance by percentage body weight allows this protocol to be used by athletes while adjusting for morphological differences.

The goal of this case series was to assess the effectiveness of the upper extremity functional testing algorithm which included not only AROM and strength but also had functional and fatigue testing. Despite the overall success of the upper extremity function testing algorithm on returning the athletes to sport, this case series consisted only of males that played Division I varsity football. Further work needs to be done on a larger number of more diverse athletes to begin to assess effectiveness across various populations, as well as over longer time frames.

CONCLUSION

The upper extremity functional testing algorithm was an effective return to sport assessment with the cohort of athletes that were tested. This is the first proposed algorithm for injured athletes that includes fatigue and functional testing along with AROM and strength to the authors’ knowledge, making it unique to upper extremity return to sport decision making. Observing the success of the athletes in this case series suggests that adding fatigue and functional testing to current return to sport practices may help improve patient outcomes and physical therapist's decision making.

Appendix 1.

Range of Motion measures from initial and discharge evaluations. X indicates not tested.

	IE PROM				DC AROM				DC PROM
	FE POS (°)	ER at 0 ° abd (°)	ER 90 ° abd (°)	IR 90 ° abd (°)	FE POS (°)	ER 0 ° abd (°)	ER 90 ° abd (°)	FIR	FE POS (°)	ER 0 ° abd (°)	ER 90 ° abd (°)	IR 90 ° abd (°)
1	105	35	X	X	175	70	90	T7	175	70	90	40
2	X	25	X	X	165	35	85	T9	170	35	88	35
3	126	25	X	X	165	60	90	T7	165	60	90	40
4	80	10	X	X	160	35	70	T9	160	35	75	30
5	110	15	X	X	165	45	90	T6	168	45	90	40
6	138	15	60	20	165	35	80	T12	168	35	85	30

FE = forward elevation; POS = plane of scapula; ER=external rotation; IR = internal rotation; abd = abduction; FIR = functional internal rotation