Glenn N. Williams

Persistent disability associated with ankle sprains: a prospective examination of an athletic population.

The purpose of this study was to examine a young athletic population to update the data regarding epidemiology and disability associated with ankle injuries. At the United States Military Academy, all cadets presenting with ankle injuries during a 2-month period were included in this prospective observational study. The initial evaluation included an extensive questionnaire, physical examination, and radiographs. Ankle sprain treatment included a supervised rehabilitation program. Subjects were reevaluated at 6 weeks and 6 months with subjective assessment, physical examination, and functional testing. The mean age for all subjects was 20 years (range, 17–24 years). There were 104 ankle injuries accounting for 23% of all injuries seen. There were 96 sprains, 7 fractures, and 1 contusion. Of the 96 sprains, 4 were predominately medial injuries, 76 were lateral, and 16 were syndesmosis sprains. Ninety-five percent had returned to sports activities by 6 weeks; however, 55% of these subjects reported loss of function or presence of intermittent pain, and 23% had a decrement of >20% in the lateral hop test when compared with the uninjured side. At 6 months, all subjects had returned to full activity; however, 40% reported residual symptoms and 2.5% had a decrement of >20% on the lateral hop test. Neither previous injury nor ligament laxity was predictive of chronic symptomatology. Furthermore, chronic dysfunction could not be predicted by the grade of sprain (grade I vs. II). The factor most predictive of residual symptoms was a syndesmosis sprain, regardless of grade. Syndesmosis sprains were most prevalent in collision sports. This study demonstrates that even though our knowledge and understanding of ankle sprains and rehabilitation of these injuries have progressed in the last 20 years, chronic ankle dysfunction continues to be a prevalent problem. The early return to sports occurs after almost every ankle sprain; however, dysfunction persists in 40% of patients for as long as 6 months after injury. Syndesmosis sprains are more common than previously thought, and this confirms that syndesmosis sprains are associated with prolonged disability.

Risk factors associated with noncontact injury of the anterior cruciate ligament: a prospective four-year evaluation of 859 West Point cadets.

Background: The causes of noncontact anterior cruciate ligament injury remain an enigma. Purpose: To prospectively evaluate risk factors for noncontact anterior cruciate ligament injuries in a large population of young athletic people. Study Design: Prospective cohort study. Methods: In 1995, 1198 new United States Military Academy cadets underwent detailed testing and many parameters were documented. During their 4-year tenure, all anterior cruciate ligament injuries that occurred were identified. Statistical analyses were used to identify the factors that may have predisposed the cadets to noncontact anterior cruciate ligament injuries. Results: Among the 895 cadets who completed the entire 4-year study, there were 24 noncontact anterior cruciate ligament tears (16 in men, 8 in women). Significant risk factors included small femoral notch width, generalized joint laxity, and, in women, higher than normal body mass index and KT-2000 arthrometer values that were 1 standard deviation or more above the mean. The presence of more than one of these risk factors greatly increased the relative risk of injury. All female cadets who had some combination of risk factors sustained noncontact anterior cruciate ligament injuries, indicating that some combinations of factors are especially perilous to the female knee. Conclusion: Several risk factors may predispose young athletes to noncontact anterior cruciate ligament injury.

Comparison of the Single Assessment Numeric Evaluation Method and Two Shoulder Rating Scales Outcomes Measures After Shoulder Surgery

The purpose of this study was to determine the correlation between the Single Assessment Numeric Evaluation method and the Rowe and American Shoulder and Elbow Surgeons scores. Between April 1993 and December 1996, 209 follow-up examinations were performed on 163 United States Military Academy cadets after shoulder surgery. These 209 examinations were divided into five follow-up categories: 3 months, 6 months, 1 year, 2 years, and greater than 2 years. The Rowe and American Shoulder and Elbow Surgeons scores from each subjects follow-up questionnaire were correlated with his or her Single Assessment Numeric Evaluation rating, which is determined by the subjects written response to the following question: “How would you rate your shoulder today as a percentage of normal (0% to 100% scale with 100% being normal)?” Correlation coefficients between the Single Assessment Numeric Evaluation and the two scores were 0.51 to 0.79 for the Rowe score and 0.46 to 0.69 for the American Shoulder Elbow Surgeons score. The results of this study indicate that the Single Assessment Numeric Evaluation correlates well with these two scores after shoulder surgery. This study suggests that this new evaluation method provides clinicians with a mechanism to gather outcomes data with little demand on their time and resources.

Syndesmotic Ankle Sprains in Athletes

Ankle sprains are among the most common athletic injuries and represent a significant source of persistent pain and disability. Despite the high incidence of ankle sprains in athletes, syndesmosis injuries have historically been underdiagnosed, and assessment in terms of severity and optimal treatment has not been determined. More recently, a heightened awareness in sports medicine has resulted in more frequent diagnoses of syndesmosis injuries. However, there is a low level of evidence and a paucity of literature on this topic compared with lateral ankle sprains. As a result, no clear guidelines are available to help the clinician assess the severity of injury, choose an imaging modality to visualize the injury, make a decision in terms of operative versus nonoperative treatment, or decide when the athlete may return to play. Increased knowledge and understanding of these injuries by clinicians and researchers are essential to improve the prevention, diagnosis, and treatment of this significant condition. This review will discuss the anatomy, mechanism of injury, diagnosis, and treatment of syndesmosis sprains of the ankle while identifying controversies in management and topics for future research.

Quadriceps Weakness, Atrophy, and Activation Failure in Predicted Noncopers After Anterior Cruciate Ligament Injury

Background Quadriceps weakness is common after anterior cruciate ligament injury, especially in those who do not compensate well for the injury (“noncopers”). Both atrophy and activation failure have been demonstrated in this population but have not been directly related to quadriceps weakness. Hypotheses (1) Quadriceps strength, volumes, and cross-sectional areas of the noncopers would be smaller than those of the contralateral muscles, whereas other muscles would not demonstrate atrophy. (2) Quadriceps muscle activation deficits would be observed. (3) Atrophy and activation failure would account for the quadriceps weakness in these patients. Study Design Cross-sectional study, Level of evidence, 3. Methods Seventeen noncopers with isolated anterior cruciate ligament injury underwent burst-superimposition strength and activation testing of the quadriceps and magnetic resonance imaging of 12 muscles an average of 2 months after injury. Morphological characteristics was described by digitally reconstructing each muscle from the axial images and calculating muscle volume and peak cross-sectional area. Results The quadriceps muscles of the anterior cruciate ligament-deficient limb were significantly weaker (average 25%) than those of the uninjured side; activation failure (8%-10%) was observed for the quadriceps muscles of both limbs. The total quadriceps, vastus lateralis, and vastus intermedius volume and cross-sectional area were significantly smaller in the anterior cruciate ligament-deficient limb. There was no significant atrophy of any other muscle or muscle group. Atrophy and activation failure explained more than 60% of the variance in quadriceps weakness (P =. 004). Conclusion The quadriceps femoris weakens soon after acute anterior cruciate ligament injury. Activation deficits and atrophy occur and affect quadriceps strength. Rehabilitation techniques that address activation deficits as well as atrophy may be necessary to restore quadriceps strength.

Comparison of the Single Assessment Numeric Evaluation method and the Lysholm score

The purpose of this study was to determine the correlation between the Lysholm knee score and the Single Assessment Numeric Evaluation method. Between March 1995 and December 1996, 201 followup examinations were performed on 130 college age patients who had undergone anterior cruciate ligament reconstructions. These 201 examinations were divided into five routine followup categories: 3 months, 6 months, 1 year, 2 years, and greater than 2 years. The Lysholm score from each patients followup questionnaire was correlated with his or her Single Assessment Numeric Evaluation rating, as determined by his or her written response to the following question: On a scale from zero to 100, how would you rate your knee today (100 being normal)? All data were gathered prospectively. The mean Lysholm scores and Single Assessment Numeric Evaluation ratings ranged from 84.0 to 93.4 points and 80.0 to 93.3 points, respectively. The correlation coefficients between the Lysholm scores and the Single Assessment Numeric Evaluation ratings ranged from 0.58 to 0.87 points. The results of this study indicate that Single Assessment Numeric Evaluation ratings correlate well with measured Lysholm scores in patients with anterior cruciate ligament reconstruction. The Single Assessment Numeric Evaluation provides clinicians with an alternative mechanism to gather outcomes data with little demand on time and resources.

Muscle and Tendon Morphology After Reconstruction of the Anterior Cruciate Ligament with Autologous Semitendinosus-Gracilis Graft

BACKGROUND The autologous semitendinosus-gracilis graft is the first choice of many orthopaedic surgeons when reconstructing the anterior cruciate ligament. The effect that graft harvest has on muscle and tendon morphology remains unclear. The purpose of this study was to describe these effects more completely. METHODS Magnetic resonance images were acquired from eight patients before the anterior cruciate ligament reconstruction with semitendinosus-gracilis autograft and then again postoperatively after they had returned to sports. Muscle and tendon morphology was described by determining the volume and peak cross-sectional area of each structure on digitally reconstructed images. The effects that the procedure had on muscle and tendon length were evaluated separately and then together as a muscle-tendon complex. RESULTS Anterior cruciate ligament reconstruction with semitendinosus-gracilis autograft resulted in a marked decrease in volume, cross-sectional area, and length of the semitendinosus and gracilis muscles. Tendon regeneration occurred in varying degrees in nearly all subjects. The morphology of the biceps femoris and semimembranosus muscles suggested that they had been compensating for the reduced semitendinosus and gracilis muscle function. Although semitendinosus and gracilis muscle retraction occurred following tendon stripping, nearly all of the subjects displayed evidence of at least partial tendon regeneration. CONCLUSIONS Anterior cruciate ligament reconstruction with semitendinosus-gracilis autograft had a marked impact on semitendinosus and gracilis muscle morphology. However, this altered muscle morphology did not appear to have a clinically important impact on short-term outcomes. The biceps femoris and semimembranosus muscles appear to compensate for reduced semitendinosus and gracilis function. Tendon regeneration is observed in most people, but it is often incomplete at six months.

Evidence-based approach to treatment of acute traumatic syndesmosis (high ankle) sprains

Ankle sprains in the athlete are one of the most common injuries, and syndesmosis or “high-ankle” sprains seem to being diagnosed at an increasing rate. As a result, there has been a heightened interest in recognizing and treating these difficult injuries on a timely basis, particularly in the athlete. Although the recognition and diagnosis of these injuries have improved, there still exists a paucity of information on optimal conservative and operative management. In this paper, a systematic review of the literature was conducted to provide an evidence-based rationale in the diagnosis and treatment of syndesmosis (high ankle) sprains in athletes. It is obvious from the low level of evidence available in the literature on this topic that a great deal of work is needed before conclusive statements regarding the management of these injuries can be made with confidence. The current diagnostic tests are not very specific. Because this is a spectrum of injury, there is a lot of variability in the time lost from sport. It is clear that we need a much more definitive diagnostic process for this injury that allows us to predict the severity of the injury, time loss from sport, and the treatment required.

Factors explaining chronic knee extensor strength deficits after ACL reconstruction

Persistent quadriceps muscle weakness is common after anterior cruciate ligament (ACL) reconstruction. The mechanisms underlying these chronic strength deficits are not clear. This study examined quadriceps strength in people 2–15 years post‐ACL reconstruction and tested the hypothesis that chronic quadriceps weakness is related to levels of voluntary quadriceps muscle activation, antagonistic hamstrings moment, and peripheral changes in muscle. Knee extensor strength and activation were evaluated in 15 ACL reconstructed and 15 matched uninjured control subjects using an interpolated triplet technique. Electrically evoked contractile properties were used to evaluate peripheral adaptations in the quadriceps muscle. Antagonistic hamstrings moments were predicted using a practical mathematical model. Knee extensor strength and evoked torque at rest were significantly lower in the reconstructed legs (p < 0.05). Voluntary activation and antagonistic hamstrings activity were similar across legs and between groups (p > 0.05). Regression analyses indicated that side‐to‐side differences in evoked torque at rest explained 71% of the knee extensor strength differences by side (p < 0.001). Voluntary activation and antagonistic hamstrings moment did not contribute significantly (p > 0.05). Chronic quadriceps weakness in this sample was primarily related to peripheral changes in the quadriceps muscle, not to levels of voluntary activation or antagonistic hamstrings activity.

Evoked tetanic torque and activation level explain strength differences by side

Previous studies have demonstrated that healthy young people typically have side-to-side differences in knee strength of about 10% when the peak torque generated by the stronger leg is contrasted with that of the weaker leg. However, the mechanisms responsible for side-to-side differences in knee strength have not been clearly defined. The current study tested the hypothesis that side-to-side knee extensor strength differences are explained by inter-limb variations in voluntary activation, antagonistic hamstrings activity, and electrically evoked torque at rest. Twenty-two volunteers served as subjects. Side-to-side differences in quadriceps activation and electrically evoked knee extensor torque explained 69% of the strength differences by side. Antagonistic hamstrings activity did not contribute significantly. The results suggest both central and peripheral mechanisms contribute to inter-limb variations in strength.