Table 1 Study characteristics

Gobbi and Francisco

Prospective

n = 100

Mean age: 28

% male: 67

PHYSICAL

1. Knee scores – Tegner, Noyes, and Marx

2. Knee specific patient reported outcome measure’s – Lysholm and International Knee Documentation Committee (IKDC)

There were no significant differences in pre-operatively mean Tegner, Noyes, Lysholm and IKDC between those who return to sport (RTS) and those who didn’t RTS.

The Marx scale showed a significant difference between athletes who were able to return to sport and those who did not return. It is however not clear from the reporting whether this was from the Marx scores taken pre-operatively or at final follow up. The authors were contacted but the corresponding email address provided on the article was no longer in use. This was therefore not included in the final analysis.

PSYCHOSOCIAL

1. Psychovitality questionnaire*

28.6% of the athletes that ‘‘did not return to sport’’ scored ≤ 15 points preoperatively. Whereas, 67% of the athletes that ‘‘returned to sport’’, scored ≥ 15 points. Statistical analysis using the Mann–Whitney U-test revealed a significant difference (P < 0.001) between these two groups (Fig. 5a, b).

DEMOGRAPHIC/CLINICAL

n/a

Marx

Minimum of 24 months

Heijne, Äng and Werner

Prospective

n = 64

Mean age: 30.1

% male: 45.3

PHYSICAL

1. Passive knee range of motion (ROM)

2. Thigh muscle torque

(Concentric quadriceps* and hamstrings, Eccentric quadriceps and hamstrings)

3. Knee function (2 questions from IKDC)

4. Anterior knee pain

PSYCHOSOCIAL

n/a

DEMOGRAPHIC/CLINICAL

1. Weight and BMI

2. Graft type*

3. Time to surgery*

Three pre-operative variables were correlated with the Tegner activity scale:

1. Concentric quadriceps torque (P = 0.004)

2. Graft type – patella tendon (P = 0.006)

3. Time between injury and reconstruction surgery (P = 0.02)

(Table 3).

These four variables explained 21% (P = 0.006) of the outcome variance. The use of a patellar tendon graft in favour of a hamstring graft was shown to be the strongest predictor in the forward step-wise regression analysis, but explained only 8% of the outcome variance (Table 4).

Tegner

12 months

(range 12–16)

Hetsroni et al.,

Retrospective

n = 55

Mean age: 25.3

% male: 100

PHYSICAL

1. Physical activity rating scales - Tegner* and Marx

Standard correlation coefficient for Tegner preinjury score as the independent variable and Tegner at follow-up as the dependent variable β^b 0.423 (0.437), p = 0.01 (< 0.01).

Standard correlation coefficient for Tegner preinjury score as the independent variable and Marx at follow-up as the dependent variable β^b 0.405 (0.457), p = 0.02 (< 0.01).

There was no correlation between the Marx pre-injury scores and follow-up Marx and Tegner scores. Standard correlation coefficient for the Marx pre-injury score as independent variable and Marx follow-up as the dependent variable β^b -0.088, p = 0.6 and for Tegner follow-up as the dependent variable β^b -0.164, p = 0.29.

PSYCHOSCOCIAL

n/a

DEMOGRAPHIC/CLINICAL

1. Time to surgery

2. Smoking status

There was no association between time to surgery and smoking status with the outcome measure.

Tegner

Marx

5–10 years

(mean 7.1 years)

Jurkonis, Gudas and Smailys

Prospective

n = 214

Mean age: 33.2

% male: 74.3

PHYSICAL

1. Physical activity rating scale - Tegner*

A positive correlation was found between pre-injury Tegner activity score and Tegner activity score 12 months after surgery

(r = 0.728, p < 0.001)

PSYCHOSCOCIAL

n/a

DEMOGRAPHIC/CLINICAL

1. BMI*

A multiple regression analysis indicated that a model including age, sex, BMI and pre-injury Tegner was a significant predictor of Tegner 12-months after ACLR, BMI (b₂= -0.042, p = 0.008).

Table 3 shows Tegner activity score pre-injury and at 12 months after ACLR in BMI groups, with statistically significant differences between Tegner activity scores in BMI groups.

Tegner

12 months

Liptak and Angel

Retrospective

n = 115

Mean age: 24

% male: 100

PHYSICAL

n/a

PSYCHOSCOCIAL

n/a

DEMOGRAPHIC/CLINICAL

1. Weight*

Player weight was identified as significantly associated with returning to play at the elite level.

Heavier players displayed a

tendency to be more likely to return to play at the elite level when compared with lighter players (70–79 kg). Players weighing between 90 and 99 kg were nearly 15 times more likely to return to play at the elite level (OR, 14.93; 95% CI, 2.13-104.76; P = 0.007).

Return to play at the elite level (AFL Medical Officers Association [AFLMOA] data)

No pre-defined time of assessment but documented as < 1 year after injury or 1 year or longer

McGrath et al.,

Prospective

n = 64

Mean age: 26.9 (LARS group) and 28.9 (2ST/2GR group)

% male: 68.8

PHYSICAL

1. Physical activity rating scale - Tegner*

Preoperative Tegner scores had a moderate correlation with postoperative activity levels at 12 (r_s = 0.347, P = 0.005) and 24 months (r_s = 0.326, P = 0.009).

PSYCHOSCOCIAL

n/a

DEMOGRAPHIC/CLINICAL

n/a

Tegner

12 and 24 months

Sonesson et al.,

Prospective

n = 65

Median age: 22

% male: 52.3

PHYSICAL

n/a

PSYCHOSCOCIAL

1. Estimation – Time to achieve postoperative markers and ability to return to preinjury level*

There were no differences between participants who had returned to their pre-injury sport activity at 1 year and those who had not returned, regarding preoperative estimated time to:

- complete rehab (n.s)

- be able to run/jump (n.s)

- return to pre-injury sport activity (n.s)

However, participants who had returned to their pre-injury sport activity at 1 year, to a greater extent estimated pre-operatively that it was possible to return to their preinjury activity level compared to those who had not returned at 52 weeks (P = 0.019, Table 4).

2. Goals

Returning to preinjury sport activity at 1 year was not related to whether participants said their goal was to return preoperatively (n.s).

DEMOGRAPHIC/CLINICAL

n/a

Return to preinjury level (unspecified)

12 months

Thomeé et al.,

Prospective

n = 38

Mean age: 29.7

% male: 65.8

PHYSICAL

1. Physical activity rating scale - Tegner*

Tegner_Pre−injury was a significant predictor (P = 0.002, β = 0.28) of Tegner_Present at the 1-year follow-up when adjusted for age, gender, K-SES_Present and K-SES_Future (R² = 0.25).

PSYCHOSCOCIAL

1. K-SES present*

The pre-operative

K-SES_Present correlated significantly (P = 0.03) (r_s = 0.37) with Tegner_Present

at the 1-year follow-up. But did not correlate significantly (P = 0.20) (r_s = 0.32) with PAS_Present at the 1-year follow-up.

2. K-SES future

The pre-operative

K-SES_Future did not correlated significantly (P = 0.56) (r_s = 0.10) with Tegner_Present or PAS_Present P = 0.76) (r_s = 0.01) at the 1-year follow-up

DEMOGRAPHIC/CLINICAL

n/a

Tegner

Physical Activity Scale (PAS)

12 months