Development and Validation of a Short Version of the Parisian Hamstring Avulsion Score (PHAS): The Short PHAS

Abstract

Background:

The Parisian Hamstring Avulsion Score (PHAS) was recently validated for the assessment of proximal hamstring avulsion repair.

Purpose:

To validate a short version of the PHAS score: the short PHAS.

Study Design:

Cohort study (Diagnosis); Level of evidence, 3.

Methods:

All patients who underwent proximal hamstring tendon avulsion repair between January 2020 and November 2023 were included. The tear was confirmed by preoperative magnetic resonance imaging. Proximal hamstring avulsion was repaired by surgical reinsertion with suture anchors. The long PHAS score, short PHAS score, and return to sport (RTS) were evaluated. The psychometric properties of the short PHAS, including its predictive value for RTS, were evaluated.

Results:

A prospective study was performed. A total of 335 patients were included in the final cohort, with a mean age of 48 ± 10 years. A subgroup of 30 patients was created to develop the short PHAS. A short PHAS score of 12 items (compared with 36 for the long version) was obtained. The internal consistency of the short version was excellent (Cronbach α = 0.85). The short PHAS was strongly correlated with the long PHAS (r = 0.94). The predictive value of both versions was moderate to good for RTS at 8 months. The predictive values of both the short and long PHAS are acceptable for RTS (area under the curve [AUC] = 0.75 for the short and 0.74 for the long PHAS), with a cutoff value of 39 of 65. Both the short and the long PHAS scores have a moderate predictive value for return to the same sport (AUC = 0.69 short vs 0.69 long PHAS), with a cut-off value of 46 of 65. Both the long and short PHAS scores have an acceptable predictive value for the return to the same sport at the preinjury level (AUC = 0.75 short vs 0.74 long PHAS), with a cutoff value of 47 of 65.

Conclusion:

The short PHAS is a reliable and valid tool to assess RTS after proximal hamstring avulsion repair.

Registration:

NCT02906865.

Keywords

hip/pelvis/thigh general sports trauma clinical assessment/grading scales hamstring proximal hamstring avulsion

Proximal avulsion of the hamstring tendon is an injury that can have severe functional consequences if it is not correctly diagnosed and managed.^3,7 Magnetic resonance imaging is the reference diagnostic technique for this event.^{3,8,19,20,23,33,40} Surgical management provides good clinical results with a good return to sport (RTS) and very few complications.^‖ These results are optimized when surgery is performed early, with, in particular, fewer recurrent tears.^{4,7,9,16,21,32,35,38,39} As understanding of these injuries has improved, specific patient-reported outcome measures (PROMs) have been developed for proximal hamstring avulsions.^{6,13,14,22,31} Indeed, outcomes of proximal hamstring tendon avulsions were initially assessed bynonspecific scores such as the Marx Activity Rating Scale, Lower Extremity Functional Scales, 12-item Short FormHealth Survey, Tegner activity scale, or the University of California, Los Angeles scale, which are not precise.^{3,9,15,17,31,34,40}

The Perth Hamstring Assessment Tool and the Sidney Hamstring Origin Rupture Evaluation scores were the first 2 published scores to specifically evaluate the results of proximal hamstring tear repairs.^4,6,13,15,30 The Parisian Hamstring Avulsion Score (PHAS) is the most recent PROM specific for hamstring tendon injuries.²² Validation of its psychometric properties was obtained in a large cohort, and it is the only specific hamstring score with predictive value for RTS. It includes 36 items and takes the patient 5 minutes to complete. This relatively short time is still too long for clinical practice.³⁷

The goal of this study was to develop and evaluate a short, reliable PHAS score and assess its predictive value for the RTS.

Methods

Study Design

This prospective single-center study was performed in a specialized sports surgery center. Patients were from the French Proximal Hamstring Avulsion Surgery Cohort Study (PHAS, CPP IDF VI, CNIL 156375).

All patients aged 18 years or older who underwent proximal hamstring tendon repair between January 2020 and November 2023 were included. Patients operated on for a recurrent tear or who did not participate in any sports were excluded.

The tear was confirmed by preoperative magnetic resonance imaging. Criteria for surgery were a complete tendon avulsion, a partial tear with >2 cm retraction, and a partial tear that did not respond to 6 months of nonoperative treatment.²⁴

Patients and Groups

The initial group included 358 patients (180 men and 178 women). A total of 23 patients were excluded because they did not practice any sport, for a final cohort of 335 patients, including 52.8% (n = 177) men. A subgroup of 30 patients (15 men and 15 women) with similar demographic characteristics to those of the main cohort was created.

Technique, Rehabilitation, and Return to Sport

Patients were operated on under spinal anesthesia using the same technique as that described by Lefèvre etal.¹⁸ Postoperative management included immobilization with an articulated knee brace at 40° of flexion for the 3 first weeks and then 10° of additional extension each week thereafter. The brace was removed once complete extension was reached. Full weightbearing was allowed 6 weeks after surgery, with gradual muscle strengthening, first with isometric exercises while wearing the brace, then with closed-chain exercises and active mobilization after week 6. After week 12, patients were allowed to jog and then gradually run, while continuing muscle strengthening, first with isokinetic and then eccentric training. They were allowed to begin their regular activities again between 16 and 32 weeks.

Outcome Measures and Endpoints

The primary outcome measures of the study were the PHAS score and the RTS. The primary endpoint of the study was the evaluation of the psychometric properties of the short version of the PHAS score.

Procedure and Analysis

The methodology was based on that described by other studies.^1,26,27,37 It follows 3 steps: item eligibility assessment, item reduction process, and scale validation process.

Item Eligibility Assessment

Before reducing the long PHAS score, a subgroup of 30 patients who had undergone proximal hamstring tendon repair in the past 12 months and whose demographic characteristics were similar to those in the main cohort evaluated the importance of each item. They were asked to grade each item on a scale of 3 (1 = not important, 2 = somewhat important, 3 = very important). To be maintained in the short PHAS, an item needed to have a mean importance score of at least 2 and to be considered at least “somewhat important” by at least two-thirds of the patients.

Item Reduction Process

The long PHAS score was then administered to all 335 patients 4 months after surgery, and items with responses that did not include any extreme values (range, 0-100) were excluded as well as items, with a mean that was not close to the center of the possible response interval (50/100), to reduce the score as much as possible.^11,37 An interitem correlation matrix was also used, and any redundant items were excluded.

To facilitate understanding of score segmentation, questions 1 to 4 were grouped under “Pain,” questions 5 to 7 under “Activity (Daily Life and Sports),” and questions 8 and 9 under “Neuropathy” (Table 1). Another criterion for item eligibility was to keep at least 1 item from each group.

Table 1

PHAS Scores at 3 Months and Relevance Scores in the Study Cohort (N = 358) ^a

Question	Category	Mean (SD)	Range (0-100)	Relevance Score
	PAIN
1	1. In the past 4 weeks or since your accident, what has been your average level of pain in your injured or operated leg?	74.92 (20.90)	0-100	2.4
2	2. How many times do you take pain medicine for your injured or operated leg?	85.94 (27.41)	0-100	2.1
3	Do you have pain, if yes, what level of pain?
	3. While resting	90.64 (15.76)	25-100	2.3
	4. While sitting	77.23 (23.49)	0-100	2.3
	5. During prolonged sitting	63.62 (26.16)	0-100	2.3
	6. During daily activities (light cleaning, cooking, doing laundry, dressing)	82.19 (20.04)	25-100	2
	7. Climbing stairs	82.40 (21.69)	0-100	2.3
	8. Going down stairs	85.89 (20.24)	0-100	2.3
	9. Walking on a flat surface	88.13 (16.59)	25-100	2.2
	10. Walking on an inclined surface	75.14 (25.25)	0-100	2.4
	11. During fast walking	64.18 (32.03)	0-100	2.4
	12. During sports/hard work	36.94 (36.12)	0-100	2.3
4	13. What is the most comfortable position for you?	77.65 (25.72)	0-100	2
	ACTIVITY (DAILY LIFE and SPORTS)
5	How much are you limited by your hamstring tendon injury (muscle weakness)
	14. During daily activities (light cleaning, cooking, doing laundry, dressing)?	86.06 (18.93)	25-100	2.2
	15. When climbing stairs?	82.91 (21.33)	0-100	2.2
	16. When going down stairs?	85.71 (20.84)	0-100	2.1
	17. When walking on a flat surface?	88.58 (17.41)	25-100	1.9
	18. When walking on an inclined surface?	75.21 (25.82)	0-100	2.1
	19. During fast walking?	60.78 (34.08)	0-100	2.1
	20. When jogging (or if no jogging: easy sports or light domestic activity)?	38.73 (39.00)	0-100	2.2
	21. During long-distance jogging (or if no jogging: sports or moderate domestic activity)?	30.18 (37.07)	0-100	2.3
	22. During very fast running, sprint (if no running: intense sports or domestic activity)?	23.88 (34.64)	0-100	2.2
	23. During intense sports/work/efforts?	30.95 (34.82)	0-100	2.3
6	24. Do you limp when you walk?	73.18 (44.36)	0-100	2.4
7	25. How would you grade your hamstring muscle function on a score of 0 (total incapacity) to 10 (optimal function) during your daily activities?	33.92 (20.55)	0-90	2.5
	NEUROPATHY
8	Are you numb and/or do you have a tingling sensation and/or superficial pins and needles on the surface of your buttocks of your injured or operated leg
	26. While resting?	82.14 (21.07)	0-100	2.4
	27. While sitting?	71.35 (24.30)	0-100	2.4
	28. During daily activities (light cleaning, cooking, doing laundry, dressing?	79.48 (22.11)	0-100	2.4
	29. During intense sports, work activities, or efforts?	49.51 (38.74)	0-100	2.3
9	Do you have sciatica-type pain (electric shock sensation) in the buttocks, thigh, from behind the knee to the foot
	30. At night?	94.68 (15.09)	25-100	2.3
	31. While resting?	93.49 (14.32)	50-100	2.2
	32. While sitting?	90.48 (19.30)	0-100	2.1
	33. During prolonged sitting?	84.52 (24.29)	0-100	2.1
	34. When walking on a flat surface?	93.70 (15.53)	0-100	2.1
	35. During fast walking?	74.72 (38.13)	0-100	2.2
	36. During intense sports or domestic activities?	49.72 (46.39)	0-100	2.2

Items retained for the short version of the Parisian Hamstring Avulsion Score (PHAS) are shown in bold.

Score Validation Process

The patients in the main cohort (335 patients) also indicated their level of RTS (no RTS, RTS to a lower level of play, RTS at the same level or better). The return to activity and sport questionnaire was administered 8 months after surgery.

After selecting the items for the short PHAS, a correlation analysis was performed to make sure that the correlation between the different versions was high despite the reduction in the number of items.

Divergent validity was evaluated by comparing the long and short PHAS scores among patients according to their RTS (no RTS, RTS at a lower level of play, RTS at a higher or the same level).

The predictive value of the long and short versions of the PHAS score for RTS was evaluated. Three analyses were performed: one to predict the RTS, one for return to the same preinjury sport, and the last for return to the same sport at the same or a higher level.

Statistical Analysis

All items were reported between 0 and 100. The mean score was reported for each item as mean ± standard deviation. Reproducibility analysis was performed using the Cronbach α test to look for possible redundancy across the analyzed versions. Validation of the presence of a correlation between the different versions was performed by the Spearman test. The comparison of the final score of each version according to the level of play was analyzed 2 × 2 using a Mann-Whitney U test. The 5% threshold was used to determine the statistical significance of the hypotheses. Statistical analysis was performed using R software from Sorbonne University (INSERM UMR S1136). The predictive validity for the RTS of each score was assessed using receiver operating characteristic (ROC) curve statistics and the Youden index. The ROC curves were determined, interpreted, and compared using the online software EasyROC (version 1.3.1).

Results

Population

The final cohort included 335 patients, with 52.8% (n = 177) men, and a mean age of 48 ± 10 years.

Item Reduction Process

The internal consistency of the long PHAS of 9 questions (36 items) was high (Cronbach α = 0.92), which suggested redundancy. The mean results for each question and each item are reported in Table 1.

The items that were not sufficiently relevant were excluded. Only item 17 was excluded at this step.The items with responses that did not include any extreme responses (range, 0-100) were then excluded. Thus, items 3, 6, 9, 14, 25, 30, and 31 were excluded. Then, it was essential for the items to have a mean close to the center of the possible response interval (50/100) with the greatest possible standard deviation (including, if possible, 50/100). At this step, items 1, 2, 4, 7, 8, 13, 15, 16, 21, 22, 26 to 28, and 32 to 34 were excluded.

Thus, the short PHAS includes items 5 and 10 to 12 from question 3 in the “Pain” category; items 18 to 20, 23, and 24 from questions 5 and 6 in the “Activity” category; and item 29 from question 8 and items 35 and 36 from question 9 in the “Neuropathy” category. The most discriminant items are usually those concerning climbing, rapid walking, and intense physical or work activities. The proposed version is presented in Table 2 and includes 12 items divided into 5 questions, rather than the 36 items divided into 9 questions of the long version.

Table 2

Proposed Version of the Short Parisian Hamstring Avulsion Score (PHAS)

Short PHAS
Question	PAIN
1	Do you have pain, if yes, how intense?
	1. During prolonged sitting?
	2. When walking on an inclined surface?
	3. During fast walking?
	4. During intense sports or work activities?
	ACTIVITY (DAILY LIFE AND SPORTS)
2	How much are you limited by your hamstring tendon (muscle weakness)
	5. When walking on an inclined surface?
	6. During fast walking?
	7. When jogging (or if no jogging: light sports or domestic activity)?
	8. During intense sports/work activities/ efforts?
3	9. Do you limp when you walk?
	NEUROPATHY
4	Are you numb and/or do you have a tingling sensation and/or superficial pins and needles on the surface of your buttocks of your injured or operated leg
	10. During intense sports/work activities?
5	Do you have sciatica-type pain (electric shock sensation) in the buttocks, thigh, from behind the knee to the foot
	11. During fast walking?
	12. During intense sports or domestic activities?

The internal consistency of the short version of 5 questions (12 items) was excellent (Cronbach α = .85), suggesting that there is no redundancy in this version. This new short version (12 items) was strongly correlated to the original long version (36 items) (r = 0.94).

Score Validation Process

Divergent Validity

At 8 months postoperatively, 18% (60/335) of patients had not returned to sport or a physical activity, 33.5% (112/335) had returned to an activity other than their preinjury sport, 32% (108/335) had returned to the same sport, and 16.5% (55/335) had returned to the same sport at the same level or higher.

Both versions of the score were significantly higher in patients who returned to another sport, to the same sport, and to the same sport at the same level compared with patients who did not return to any physical activity. The results of both versions of the score for RTS and at the level of play at 8 months postoperatively are reported in Table 3.

Table 3

Comparison of Different Versions of the Parisian Hamstring Avulsion Score (PHAS) at 4 Months According to Sports Activity and Level at 8 Months Postoperatively

Activity Level at 8 Months (n = 335) ^a	Total PHAS ^b	Short PHAS ^b
No return, n = 60	133.9 ± 28.1 ^{c , d , e}	34.5 ± 14 ^{c , d , e}
Return to sport but to a different sport, n = 112	148.5 ± 22.5 ^{c , f , g}	42 ± 12.2 ^{c , f , g}
Return to the same sport, n = 108	155.2 ± 23.7 ^{d , f , h}	45.9 ± 12.2 ^{d , f , h}
Return to the same sport at the same level, n = 55	168.2 ± 16.7 ^{e , g , h}	52.9 ± 9.7 ^{e , g , h}

A total of 23 patients did not practice any sport at surgery.

Data are reported as mean ± standard deviation.

P < .001, no return versus return to a different sport.

P < .0001, no return versus return to the same sport.

P < .0001, no return versus return to the same sport at the same level.

P = .01, return but to a different sport versus return to the same sport.

P < .0001, return but to a different sport versus return to the same sport at the same level.

P < .001, return to the same sport versus return to the same sport and the same level.

Predictive Value

Return to Sport

The RTS in the entire population was 77.5% (275/335), including 58.7% (220/335) who returned to another sport or at a lower level of play and 16.4% to the same sport at the same or a higher level.

The predictive value of both versions of the PHAS (long and short) was moderate to good for the RTS at 8 months.

Figure 1.

Receiver operating characteristic curves for the prediction at 8 months postoperatively of the return to any sports or physical activity (A), the same sport (B), the same sport at the same level (C), and according to the different versions of the Parisian Hamstring Avulsion Score completed at 4 months (Figure 1).

The short PHAS, like the long version, had an acceptable predictive value for RTS with AUCs of 0.73 (95% CI, 0.65-0.8) and 0.72 (95% CI, 0.65-0.8), respectively.²⁹ The predictive threshold was 39 of 65 for the short version (Youden = 0.39, sensitivity = 72%, specificity = 67%) and 147/200 for the long version (Youden = 0.4, sensitivity = 70%, specificity = 81%). The predictions for the subgroup according to the type of sport, presented in Table 4, did not show any significant difference between the subgroups

Table 4

Prediction of Return to Any Sport at 8 Months According to Different PHAS Versions ^a

Sport Level	AUC (95% CI)	Youden Index	Associated Score	Sensitivity, %	Specificity, %	P Value
Whole population, N = 335
Long PHAS	0.72 (0.65-0.80)	0.4	147	70	70	—
Short PHAS	0.73 (0.65-0.80)	0.39	39	72	67	.91
Professional sports, n = 16
Long PHAS	—	—	—	—	—	—
Short PHAS	—	—	—	—	—	—
Competition sports, n = 88
Long PHAS	0.80 (0.64-0.94)	0.56	148	78	77	—
Short PHAS	0.79 (0.64-0.94)	0.60	39	82	78	.95
Regular sports, n = 193
Long PHAS	0.68 (0.58-0.79)	0.34	146	65	69	—
Short PHAS	0.69 (0.59-0.79)	0.31	35	77	54	.91
Occasional sports, n = 38
Long PHAS	0.69 (0.51-0.86)	0.39	147	63	75	—
Short PHAS	0.69 (0.51-0.86)	0.41	38	73	69	.97
Contact pivot sports, n = 69
Long PHAS	0.69 (0.51-0.87)	0.33	143	91	42	—
Short PHAS	0.69 (0.51-0.87)	0.38	49	72	67	.95
Isolated pivot sports, n = 61
Long PHAS	0.70 (0.50-0.91)	0.46	126	92	54	—
Short PHAS	0.71 (0.48-0.93)	0.43	24	98	46	.98
Nonpivot sports, n = 205
Long PHAS	0.75 (0.66-0.83)	0.47	147	66	81	—
Short PHAS	0.75 (0.66-0.83)	0.41	40	65	76	.96

In total, 23 sedentary patients did not practice any sports at surgery and were excluded from the study. All professional athletes resumed physical activity at 8 months, making this analysis impossible. AUC, area under the curve; PHAS, Parisian Hamstring Avulsion Score.

Return to the Same Sport

The short PHAS, like the long PHAS, had a moderate predictive value for return to the same sport, with AUCs of 0.69 (95% CI, 0.63-0.75) and 0.69 (95% CI, 0.63-0.75), respectively.²⁹ The predictive threshold was 46 of 65 for the short version (Youden = 0.29, sensitivity = 65%, specificity = 64%) and 153 of 200 for the long version (Youden = 0.31, sensitivity = 62%, specificity = 69%). The predictions by subgroup according to the type of sport and the level of play are presented in Table 5, with no significant difference between the subgroups.

Table 5

Prediction of Return to the Same Sport at 8 Months Postoperatively According to Different PHAS Versions ^a

Level of Play	AUC (95% CI)	Youden Index	Associated Score	Sensitivity, %	Specificity, %	P Value
Whole population, N = 335
Long PHAS	0.69 (0.63-0.75)	0.31	153	62	69	—
Short PHAS	0.69 (0.63-0.75)	0.29	46	65	64	.92
Professional, n = 16
Long PHAS	0.60 (0.25-0.94)	0.36	170	36	100	—
Short PHAS	0.71 (0.43-0.99)	0.45	51	45	100	.62
Competitive, n = 88
Long PHAS	0.71 (0.59-0.82)	0.36	159	77	59	—
Short PHAS	0.71 (0.59-0.83)	0.35	47	79	56	.97
Regular sports, n = 193
Long PHAS	0.65 (0.57-0.72)	0.26	154	64	63	—
Short PHAS	0.65 (0.57-0.72)	0.24	35	84	40	.96
Occasional sports, n = 38
Long PHAS	0.82 (0.66-0.98)	0.61	150	87	73	—
Short PHAS	0.80 (0.65-0.96)	0.57	38	100	57	.86
Contact pivot sports, n = 69
Long PHAS	0.73 (0.61-0.85)	0.39	175	56	83	—
Short PHAS	0.73 (0.61-0.85)	0.43	53	74	53	.99
Isolated pivot sports, n = 61
Long PHAS	0.71 (0.58-0.85)	0.41	154	72	69	—
Short PHAS	0.73 (0.59-0.86)	0.35	35	91	52	.88
Nonpivot sports, n = 205
Long PHAS	0.71 (0.63-0.78)	0.35	157	58	77	—
Short PHAS	0.71 (0.63-0.78)	0.32	39	76	56	.98

In total, 23 sedentary patients did not practice any sports at surgery and were excluded from the study. AUC, area under the curve; PHAS, Parisian Hamstring Avulsion Score.

Return to the Same Sport at the Same Level

The short PHAS and the long PHAS had acceptable predictive values for return to the same sport at the same level of play, with AUCs of 0.75 (95% CI, 0.67-0.81) and 0.74 (95% CI, 0.67-0.81), respectively.²⁹ The predictive threshold was 47 for the short PHAS (Youden = 0.38, sensitivity = 60%, specificity = 78%) and 155 for the long PHAS (Youden = 0.4, sensitivity = 56%, specificity = 84%). The predictions by subgroup according to the type of sport and the level of play, reported in Table 6, did not show any significant differences between the groups.

Table 6

Prediction of Return to the Same Sport at the Same Level at 8 Months Postoperatively According to Different PHAS Versions ^a

Level of Play	AUC (95% CI)	Youden Index	Associated Score	Sensitivity, %	Specificity, %	P Value
Whole population, N = 335
Long PHAS	0.74 (0.67-0.81)	0.4	155	56	84	—
Short PHAS	0.75 (0.67-0.81)	0.38	47	60	78	.94
Professional n = 16
Long PHAS	0.52 (0.18-0.87)	0.34	161	54	80	—
Short PHAS	0.48 (0.13-0.83)	0.15	46	55	60	.86
Competitive, n = 88
Long PHAS	0.72 (0.60-0.84)	0.39	159	94	44	—
Short PHAS	0.71 (0.59-0.83)	0.4	48	94	46	.91
Regular sports practice, n = 193
Long PHAS	0.74 (0.65-0.83)	0.4	150	90	51	—
Short PHAS	0.74 (0.65-0.84)	0.38	47	76	62	.97
Occasional sports, n = 38
Long PHAS	0.99 (0.98-1.00)	0.97	184	100	97	—
Short PHAS	0.98 (0.93-1.00)	0.97	59	100	97	.45
Contact pivot sports, n = 69
Long PHAS	0.73 (0.58-0.87)	0.33	181	50	91	—
Short PHAS	0.73 (0.60-0.87)	0.39	60	50	89	.93
Isolated pivot sports, n = 61
Long PHAS	0.70 (0.53-0.87)	0.39	159	77	62	—
Short PHAS	0.66 (0.49-0.82)	0.29	44	77	52	.69
Nonpivot sports, n = 205
Long PHAS	0.77 (0.68-0.87)	0.49	155	89	60	—
Short PHAS	0.76 (0.68-0.84)	0.48	48	85	65	.88

In total, 23 sedentary patients did not practice any sports at surgery and were excluded from the study. AUC, area under the curve; PHAS, Parisian Hamstring Avulsion Score.

Discussion

The main result of this study is that the long PHAS score with 36 items can be shortened to a version with 12 items without changing its psychometric properties and with the same predictive value for RTS.

The methodology used results in a short PHAS score that is strongly correlated with the long PHAS score (r = 0.94) and is more effective, with an optimal Cronbach α value of 0.85, showing the absence of redundancy because it is between 0.8 and 0.9.³⁶

The PHAS score is the only specific published PROM with predictive value for RTS after proximal hamstring tendon avulsion repair, and this value is maintained in the short PHAS.²² This element is essential to have a simple, reliable clinical assessment of the patient's readiness to RTS. This score is especially interesting to predict a return to any sports activity, with a sensitivity of 72%, a specificity of 67%, and a Youden index of 0.39 for a score of 39 of 65, as well as a return to the same preinjury sport at the same level, with a sensitivity of 60%, a specificity of 78%, and a Youden index of 0.38 for a score of 47 of 65. However, the score is less effective in predicting return to the same sport at a different level of play, with a lower sensitivity and specificity and a Youden index of 0.29 for a score of 46 of 65. This is not surprising because this notion is more subtle clinically. Nevertheless, the sensitivities and specificities, as well as the relatively lower Youden index, are a reminder that this score is not the only way to determine a patient's readiness to RTS. Indeed, assessment of RTS should be multifactorial and include a battery of tests and the short PHAS as a major element.^{2,3,10,12,19,25,31} The time saved with the short PHAS is all the more important because assessment of RTS includes several scores and tests that are systematically administered to patients, and it is time-consuming.^26,27,37 Short versions facilitate data collection and allow more widespread use of PROMs by improving adherence by both patients and practitioners. It is therefore logical to see an increase in the number of “short” versions of the PROMs that are the most frequently used in different medical specialties, particularly sports medicine.^26,27,37

Limitations

This study has several limitations. First, we did not compare the short PHAS to the other published scores, in particular, the Perth Hamstring Assessment Tool and the Sidney Hamstring Origin Rupture Evaluation, so the external validity of the short PHAS was not explored. Finally, the predictive value of the short PHAS at 6 and 9 months for RTS at 1 year would also have been interesting and should be evaluated in further studies.

Conclusion

The short PHAS is a reliable, validated tool that is simple to perform to assess outcomes after proximal hamstring avulsion repair. It can also be used to predict RTS.

Footnotes

Final revision submitted September 23, 2025; accepted November 4, 2025.

One or more of the authors has declared the following potential conflict of interest or source of funding: A.H. is a consultant for Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Ethical approval for this study was obtained from Groupe Hospitalier Pitié-Salpêtrierè, Paris, France.

ORCID iDs

Sammy Kassab Hassan

Mohamad Moussa

Alexandre Hardy

Notes

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