Table 1

Follow up studies on the rate of return to sport, risk of re-rupture, and the prevalence of radiological osteoarthritis after an initial anterior cruciate ligament (ACL) injury

Study	Material	Operative/Non-operative	Return to sport	Follow up (years)	Re-rupture	Osteoarthrosis	Remarks
A total of 540 papers were identified through a Medline search using the following key words: “Anterior Cruciate Ligament/*injuries” AND “Follow-Up Studies”. Abstracts were reviewed to identify studies reporting on the return rate to sport, the reinjury rate, and/or the prevalence of osteoarthritis with a mean follow up period of at least four years. In addition, reference lists of selected papers were reviewed to identify additional studies. Follow up studies describing partial ACL ruptures or reconstructive surgery with sutures only were excluded. A single or double asterisk is used to indicate which piece of information the remark in the Remarks column is referring.
Op, Operative; Non-op, non-operative; BPTB, bone-patella-tendon-bone graft; STG, single strain gracilis; Hamstrings, includes semitendinosus, gracilis and iliotibial grafts; LAD, Kennedy ligament augmentation device.
Von Porat et al¹⁴	N = 205; age, 38 (30–56)	89/65*	7.8% (9 op & 3 non-op)	14	–	78%** in both groups	*154 answered questionnaire
	Soccer male						**122 players with radiological exam
McDaniel & Dameron³²	N = 50 (53 knees)	Non-operative	74%*	14	–	86%	*Returned to strenuous sport
Fink et al¹³	N = 71 (84%) in sports activity Skiing: 63%, Soccer: 24%	46/25	44% reduction in op/70% reduction in non-op*	10–13	0	78%/83%	*Reduction in high risk sports participation
Myklebust et al⁹	N = 79 (♂: 29, ♀: 50)	57/22	58%/82%	6–11	13% *	42%/46%**	*BPTB reconstructed
	Team handball						**Radiological exam of 50 players
Drogset & Grøntvedt²¹	N = 100 (♂: 45, ♀: 55)	Reconstruction with LAD (n = 49)	–	8	12%*	50%	*All occurred in pivoting activities
	Different sports activities	Without LAD (n = 51)
Roos et al¹⁰	N = 310 (♂: 213, ♀: 97)	157/153	22%/19%*	7	–	Not examined	None of the players played at the same level as before injury
	Soccer
Ruiz et al³³	N = 30 (♂: 21/♀: 9)	Reconstruction	12 patients changed first choice sport*	7 (5–9)	3.3%	50%	*Change not attributed to knee pathology alone
	Football: 11 Rugby: 12 Other: 7	STG: 4
		BPTB: 26
Johma et al³⁴	N = 59	BPTB	–	7	10%	57%
Scavenius et al³⁵	N = 33 (♂: 20/♀: 13)	Non-operative	9%	7	–	Not examined
	Mostly soccer, handball, alpine skiing
Jennings et al³⁶	N = 50 (♂: 32/♀: 18)	BPTB	32% same level, 94% lower level	5.2	–	Not examined
Brandsson et al²⁸	N = 102* (♂: 74/♀: 38)	BPTB	–	4–7	2.9%	Not examined	*The 3 players with re-rupture were excluded
Howe et al³⁷	N = 83	BPTB	–	5	–	37%*	*Reported medial joint space narrowing
Pinczewski et al³⁸	N = 180 (♂: 95/♀: 85)*	BPTB: N = 90	–	5	BPTB: 3%	12%**	No information on sports participation. *BPTB: 18%
		Hamstrings: N = 90			Hamstrings: 8%		Hamstrings: 4%
Otto et al¹⁹	N = 68 (♂: 49/♀: 19)	BPTB	38% preinjury level, 15% higher level	5	4.4%	24%
	Pivoting/side stepping sports
Sandberg & Balkfors¹⁸	N = 112 (♂: 75/♀: 37)	BPTB	35% returned to same level (soccer)	5	9.8%	Not examined
	Different sports, soccer:72%		25% quit, rest only fitness training	(2–11)
Ferretti et al³⁹	N = 114	Hamstrings	67% same level	5	–	25.4%	*No description of type of sports
			32% reduced participation
			1 increased level *
Cooley et al⁴⁰	N = 33	Hamstrings	45% maintained activity level	5	3%**	5%	*Not due to knee limitations
			55% reduced activity level*				**Was excluded from follow up together with patient with meniscectomy
Patel et al⁴¹	N = 32 (♂: 8/♀: 24)	BPTB	41%	5	9%	28%
	88% from “sporting activities”
Wang et al⁴²	N = 44 (♂: 32/♀: 12)	BPTB	–	4.8	–	61%
	2/3 sports related
Bak et al⁴³	N = 132(♂: 117/♀: 15)	Hamstrings	68% same level	4	3%*	Not examined	*20% among females
	Soccer		29% lower level