Neuromuscular Evaluation With Single-Leg Squat Test at 6 Months After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Criteria for return to unrestricted activity after anterior cruciate ligament (ACL) reconstruction varies, with some using time after surgery as the sole criterion-most often at 6 months. Patients may have residual neuromuscular deficits, which may increase the risk of ACL injury. A single-leg squat test (SLST) can dynamically assess for many of these deficits prior to return to unrestricted activity. HYPOTHESIS: A significant number of patients will continue to exhibit neuromuscular deficits with SLST at 6 months after ACL reconstruction. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients using a standardized accelerated rehabilitation protocol at their 6-month follow-up after primary ACL reconstruction were enrolled. Evaluation included bilateral SLST, single-leg hop distance, hip abduction strength, and the subjective International Knee Documentation Committee (IKDC) score. RESULTS: Thirty-three patients were enrolled. Poor performance of the operative leg SLST was found in 15 of 33 patients (45%). Of those 15 patients, 7 (45%) had concomitant poor performance of the nonoperative leg compared with 2 of 18 patients (11%) in those who demonstrated good performance in the operative leg. The poor performers were significantly older (33.6 years) than the good performers (24.2 years) (P = .007). Those with poor performance demonstrated decreased hip abduction strength (17.6 kg operative leg vs 20.5 kg nonoperative leg) (P = .024), decreased single-leg hop distance (83.3 cm operative leg vs 112.3 cm nonoperative leg) (P = .036), and lower IKDC scores (67.9 vs 82.3) (P = .001). CONCLUSION: Nearly half of patients demonstrated persistent neuromuscular deficits on SLST at 6 months, which is when many patients return to unrestricted activity. Those with poor performance were of a significantly older age, decreased hip abduction strength, decreased single-leg hop distance, and lower IKDC subjective scores. CLINICAL RELEVANCE: The SLST can be used to identify neuromuscular risk factors for ACL rupture. Many patients at 6 months have persistent neuromuscular deficits on SLST. Caution should be used when using time alone to determine when patients can return to unrestricted activity.

Clinical follow-up of professional baseball players undergoing ulnar collateral ligament reconstruction using the new Kerlan-Jobe Orthopaedic Clinic overhead athlete shoulder and elbow score (KJOC Score).

BACKGROUND: There are no validated outcome measures consistently used in the literature to report results of ulnar collateral ligament reconstruction in overhead athletes. HYPOTHESIS: The Kerlan-Jobe Orthopaedic Clinic Overhead Athlete Shoulder and Elbow score (KJOC score) will correlate with other validated scores for upper extremity assessment but will be more accurate in evaluating ulnar collateral ligament reconstruction outcomes in professional baseball players. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Fifty-five professional baseball players who underwent ulnar collateral ligament reconstruction were asked to complete the KJOC score, the Disabilities of the Arm, Shoulder and Hand (DASH) score, and the DASH sports module. Players were separated into 3 categories-(1) playing without pain, (2) playing with pain, and (3) not playing because of pain-and compared with 123 asymptomatic throwers. Pearson (parametric) and Spearman rank (nonparametric) correlations among the 3 systems were conducted to validate the KJOC score. Means across categories were compared using a Wilcoxon rank-sum test, and a threshold score separating categories 1 and 3 was determined using receiver operator characteristic discrimination analysis. RESULTS: Significant correlations were found between the KJOC score and the DASH (-.693, P < .0001), and the DASH sports module (-0.804, P < .0001). Only the KJOC score was able to discriminate between categories 2 and 3, as well as category 1 and the uninjured population. In addition, the KJOC score was the most sensitive and accurate method of discriminating category 1 from category 3, with a threshold score of 81.3. CONCLUSION: The results of this study validate the use of the KJOC score for evaluation of overhead athletes undergoing ulnar collateral ligament reconstruction. The KJOC score is the most sensitive score for detecting subtle changes in performance in the throwing athlete.

The effect of pitching biomechanics on the upper extremity in youth and adolescent baseball pitchers.

BACKGROUND: Increased pitch counts have been linked to increased complaints of shoulder and elbow pain in youth baseball pitchers. Improper pitching mechanics have not been shown to adversely affect the upper extremity in youth pitchers. HYPOTHESIS: The correct performance of 5 biomechanical pitching parameters correlates with lower humeral internal rotation torque and elbow valgus load, as well as higher pitching efficiency, in youth and adolescent pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: In sum, 169 baseball pitchers (aged 9-18) were analyzed using a quantitative motion analysis system and a high-speed video while throwing fastballs. The correct performance of 5 common pitching parameters was compared with each pitcher's age, humeral internal rotation torque, elbow valgus load, and calculated pitching efficiency. RESULTS: Motion analysis correlated with video analysis for all 5 parameters (P < .05). Youth pitchers (aged 9-13) performing 3 or more parameters correctly showed lower humeral internal rotation torque, lower elbow valgus load, and higher pitching efficiency (P < .05). CONCLUSIONS: Youth pitchers with better pitching mechanics generate lower humeral internal rotation torque, lower elbow valgus load, and more efficiency than do those with improper mechanics. Proper pitching mechanics may help prevent shoulder and elbow injuries in youth pitchers. CLINICAL RELEVANCE: The parameters described in this study may be used to improve the pitching mechanics of youth pitchers and possibly reduce shoulder and elbow pain in youth baseball pitchers.

Electromyographic analysis of forearm muscles in professional and amateur golfers.

BACKGROUND: No fine-wire electromyography studies have been performed to compare the activity of forearm muscles in professional golfers versus amateur golfers. HYPOTHESIS: The fine-wire electromyographic activity of forearm muscles differs between professional and amateur golfers during the different phases of the golf swing. STUDY DESIGN: Controlled laboratory study. METHODS: Ten male right-handed amateur golfers and 10 male right-handed professional golfers without history of elbow symptoms were tested with fine-wire electromyographic electrodes inserted into the flexor carpi radialis, pronator teres, flexor carpi ulnaris, and extensor carpi radialis brevis muscles of both forearms. Electromyographic data were synchronized with video data, and the muscle activity was expressed as a percentage of maximum manual muscle test activity for each phase of the golf swing. RESULTS: Compared with professional golfers, amateur golfers had more muscle activity in the pronator teres of the trail arm (right arm in a right-handed golfer) in the forward swing phase (120.9% maximum manual muscle test vs 57.4% maximum manual muscle test; P = .04) and a trend toward increased activity in the acceleration phase (104.8% maximum manual muscle test vs 53.1% maximum manual muscle test; P = .08). In contrast, professional golfers had more muscle activity in the pronator teres of the lead arm (left arm in a right-handed golfer) in the acceleration phase (88.1% maximum manual muscle test vs 36.3% maximum manual muscle test; P = .03) and a trend toward increased activity in the early follow-through phase (58.1% maximum manual muscle test vs 28.8% maximum manual muscle test; P = .06). CONCLUSION: Pronator teres muscle activity in the golf swing differs significantly between professional and amateur golfers. CLINICAL RELEVANCE: Exercises with an emphasis on stretching and strengthening of the pronator teres may be useful in treating and/or preventing medial epicondylitis in amateur golfers.

The effect of tennis racket grip size on forearm muscle firing patterns.

BACKGROUND: Inappropriately sized tennis racket grip is often cited in the popular media as a risk factor for overuse injuries about the forearm and elbow. Currently, a hand measurement technique developed by Nirschl is commonly used by tennis racket manufacturing companies as the method for determining a player's "recommended" grip size. HYPOTHESIS: Quarter-inch changes from that recommended by Nirschl in tennis racket grip size will have no significant effect on forearm muscle firing patterns. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen asymptomatic Division I and II collegiate tennis players performed single-handed backhand ground strokes with rackets of 3 different grip sizes (recommended measurement, undersized (1/4) in, and oversized (1/4) in). Fine-wire electromyography was used to measure muscle activity in extensor carpi radialis longus and brevis, extensor digitorum communis, flexor carpi radialis, and pronator teres. Repeated-measure analysis of variance was used for within-group comparisons, comparing different grips in specified phases for backhand ground strokes (P

Electromyography of the quadriceps in patellofemoral pain with patellar subluxation.

This study compared muscle activity and timing of gait phases during functional activities in 13 subjects with patellofemoral pain associated with lateral subluxation and in 11 subjects with healthy knees. Fine wire electromyography recorded activity in the vastus lateralis and vastus medialis oblique during walking and ascending and descending stairs. Subjects were filmed to divide the activities into phases and determine timing. The vastus medialis oblique and vastus lateralis had similar patterns during all activities. Subjects with patellofemoral pain had significantly increased activity in the vastus medialis oblique and vastus lateralis compared with the healthy subjects during the most demanding phases of the gait cycle, suggesting a generalized quadriceps weakness in the patients with patellofemoral pain. Timing differences were seen in walking and stair ascending with the subjects with patellofemoral pain spending significantly more time in stance compared with the healthy subjects. This may be an attempt to reduce the load on weak quadriceps. These data reflect a generalized quadriceps muscle weakness, rather than the prevailing theory of quadriceps muscle imbalance as an etiology of patellofemoral pain. Therefore, we support the practice of strengthening the entire quadriceps muscle group, rather than attempting to specifically target the vastus medialis oblique.

The effects of home interferential therapy on post-operative pain, edema, and range of motion of the knee.

OBJECTIVE: We studied the effects of home interferential current therapy (IFC) on postoperative pain, range of motion, and edema in subjects undergoing anterior cruciate ligament (ACL) reconstruction, menisectomy, or knee chondroplasty. DESIGN: Randomized, double-blind, placebo-controlled prospective study. SETTING: A tertiary care outpatient orthopaedic clinic/ambulatory surgery center. SUBJECTS OR PARTICIPANTS: Eighty-seven subjects were separated into three groups based on their type of knee surgery and within each group randomized into a treatment or placebo group. INTERVENTIONS: All subjects received home IFC units. Subjects randomized to treatment group received a working IFC unit. Placebo subjects received units that were previously set to deliver no current. MAIN OUTCOME MEASUREMENTS: Post-operative edema at 24, 48, and 72 hours, and weeks 1-8; range of motion at 1, 3, 6, and 9 weeks; pain immediately after surgery, at 24, 48, and 72 hours, and weeks 1-7; and amount of pain medication taken at days 1-10 were compared between treatment and placebo groups. RESULTS: All IFC subjects reported significantly less pain and had significantly greater range of motion at all post-operative time points. ACL and menisectomy IFC subjects experienced significantly less edema at all time points, while chondroplasty subjects experienced significantly less edema until 4 weeks postoperatively. CONCLUSIONS: These findings indicate that home IFC may help reduce pain, pain medication taken, and swelling while increasing range of motion in patients undergoing knee surgery. This could result in quicker return to activities of daily living and athletic activities.

Disorders of the superior labrum: review and treatment guidelines.

Advancements in shoulder arthroscopy have led to a better understanding of the anatomy and disorders of the superior labrum biceps tendon anchor complex and the role that lesions of the superior labrum anterior and posterior lesions play in pain and instability of the shoulder. Various injury mechanisms have been suggested and studied and it is likely that different mechanisms produce different types and areas of damage to the superior labrum. Classification systems have been proposed to describe the specific pathoanatomy of lesions of the superior labrum anterior and posterior lesions and to guide treatment. Presenting symptoms often are nonspecific and physical examination maneuvers have varying degrees of sensitivity and specificity making diagnosis challenging. Diagnostic ability is enhanced by the ultimate diagnostic test, arthroscopy. A clear appreciation for the various lesions and the potential resulting joint dysfunction is necessary to determine the appropriate treatment of this complex region of the shoulder. The current authors review the anatomy, classification, presentation, evaluation and treatment results of superior labrum anterior and posterior lesions, and includes novel evaluation methods and treatment guidelines useful in treating these lesions.