Spine & Sports Institute

Background: No case series of isolated complete rupture of the distal semitendinosus tendon have been reported previously.

Purpose: This study was undertaken to increase awareness and report the authors’ treatment experience, particularly the less than favorable results of nonoperative initial treatment.

Study Design: Case series; Level of evidence, 4.

Methods: The authors identified 25 cases of distal semitendinosus tendon rupture over a 14-year period (1991-2005). All players were male professional (20), collegiate (4), or high-level amateur (1) athletes. Follow-up of 17 cases averaged 13 months (range, 4-55), and 8 patients were lost to follow-up. Eight Major League Baseball, 8 National Football League, and 1 National Hockey League athletes were included in this study. Early treatment experience always involved nonoperative treatment, including rest, modalities, and rehabilitation exercises, followed by functional progression. “Recovery” was defined by clinical criteria including clearance to return to play. Failure to improve with nonoperative treatment, and thus requiring surgical treatment, was deemed a failure of nonoperative treatment. There were 12 players who had initial nonoperative treatment. The authors had later experience with 5 players who had surgery early in the acute phase in hopes of speeding return to competition.

Results: In the nonoperative treatment group (12), 7 players recovered at an average of 10.4 weeks (range, 3-35). Five of these players (42%) failed initial nonoperative treatment (mean, 16.8 weeks) and subsequently had surgery to resect the torn tendon and surrounding scar tissue. These 5 players recovered at an average of 12.8 weeks postoperatively. In the acute surgery group, 5players had surgery to resect the torn tendon and scar tissue within 4 weeks of injury. The acute-phase group had an average recovery of 6.8 weeks after surgery.

Conclusion: Distal semitendinosus ruptures frequently (42%) do not recover after nonoperative treatment. Acute surgical resection of the completely ruptured semitendinosus tendon may speed recovery when the athlete has a tender mass and difficulty extending the knee fully in the stance phase of gate. Future investigation is warranted to compare the long-term outcome of nonoperative treatment with that after acute surgery.

1. Daniel E. Cooper, MD†* and
2. John E. Conway, MD‡

Background: Very little information is available regarding the incidence, causative mechanisms, and expected duration of time lost after injuries to kickers (placekickers and punters) in American football.

Hypothesis: Lower extremity musculotendinous injuries are the most common type of injury in American football kickers. The injuries related to punting differ from injuries related to placekicking.

Study Design: Descriptive epidemiologic study.

Methods: A retrospective review of all documented injuries to kickers in the National Football League over a 20-year period (1988-2007) was performed using the League’s injury surveillance database. The data were analyzed from multiple perspectives, with emphasis on the type of kick or activity at the time of injury and the factors that affect return to play after injury.

Results: There were 488 total injuries over the 20-year period: 72% involved the lower extremity, 9% involved the lumbosacral spine, and 7% involved the head. Muscle-tendon injuries (49%) were the most common, followed by ligamentous injuries (17%). There was a significantly higher risk of injury in games (17.7 per 1000) than during practice (1.91 per 1000). Most injuries (93%) did not require surgery, and the mean time to return to play was 15 days if no surgery was necessary. Kickers over 30 years of age took longer to return to play (mean, 21 days) than younger kickers (mean, 12 days) after nonsurgical injuries (P = .03). Mean return to play after injuries that required surgery was 121 days. Lumbosacral soft tissue injury, lateral ankle sprains, and shoulder injuries were more likely to occur in punters than placekickers.

Conclusion: Kicking athletes face a low risk of injury in professional American football. Injuries most commonly involve the lower extremities. Training and injury prevention efforts should reflect that punting is associated with different injuries than placekicking, and that older kickers take longer to recuperate than younger kickers after certain injuries.

1. Robert H. Brophy, MD*†,
2. Rick W. Wright, MD†,
3. John W. Powell, PhD‡ and
4. Matthew J. Matava, MD†

Background: Strain injuries of the posterior thigh are common in soccer. It seems that previous injury and age are important risk factors, but the literature is limited. This study was conducted to see if we could identify intrinsic risk factors for hamstring injuries among male soccer players.

Hypothesis: We hypothesized that previous hamstring injuries, reduced function scores, abnormalities on a clinical examination, high maximum sprint speed, poor hamstring strength, or low hamstring/quadriceps ratio can predict increased risk of new hamstring injuries.

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

Methods: A total of 508 players representing 31 amateur teams were tested during the 2004 preseason for potential risk factors for hamstring injury through a questionnaire on previous injury and function score (Hamstring Outcome Score [HaOS]), a clinical examination of the hamstring, and specific hamstring relevant tests. Generalized estimating equations were used in univariate analyses to identify candidate risk factors, and factors with a P value of <.10 were then examined in a multivariate model.

Results: During the soccer season, 76 hamstring injuries, affecting 65 legs (61 players), were registered. Univariate analyses revealed previous acute hamstring injury (yes/no) (odds ratio [OR], 2.62; 95% confidence interval [CI], 1.54-4.45), HaOS function score with all subscores except “Soreness” (OR for a 10-point difference in total score, 1.29; 95% CI, 1.08-1.54), age (OR, 1.25; 95% CI, 0.96-1.63), and player position (P = .09) as candidate predictors of high injury risk. In a multivariate analysis, the most important risk factor for injuries to the hamstring was previous acute hamstring injury (yes/no) (adjusted OR, 2.19; 95% CI, 1.19-4.03; P = .01).

Conclusion: In a multivariate analysis, previous acute hamstring injury was found to be a significant risk factor for new hamstring injuries. Previously injured players have more than twice as high a risk of sustaining a new hamstring injury.

1. Anders Hauge Engebretsen, MD*†,
2. Grethe Myklebust, PT, PhD†,
3. Ingar Holme, PhD†,
4. Lars Engebretsen, MD, PhD†‡ and
5. Roald Bahr, MD, PhD†

1. Anders Hauge Engebretsen, MD
2. Grethe Myklebust, PT, PhD
3. Ingar Holme, PhD
4. Lars Engebretsen, MD, PhD
5. Roald Bahr, MD, PhD

Am J Sports Med June 2010 38:1147-1153; published online before print March 24, 2010, doi:10.1177/036354650935838